* [PATCH 0/6] BTF ABI
@ 2021-06-11 15:33 Giuliano Procida
2021-06-11 15:33 ` [PATCH 1/6] Tweak clang-format Giuliano Procida
` (6 more replies)
0 siblings, 7 replies; 14+ messages in thread
From: Giuliano Procida @ 2021-06-11 15:33 UTC (permalink / raw)
To: libabigail; +Cc: dodji, kernel-team, gprocida, maennich, teguiani
Hi.
This code was developed by Maria Teguiani who interned with Android
last summer and later by me.
BTF is the BPF type format.
See: https://www.kernel.org/doc/html/latest/bpf/btf.html
The Linux kernel can be compiled with BTF type information. Together
with the kernel and ELF symtabs, it can be used to as an alternative
basis for kernel ABI monitoring.
BTF has several limitations compared with libabigail ABI XML.
Foremost, it supports C types only. There are also some other
significant issues that may be resolved with time. The simplicity of
BTF makes it an ideal vehicle for experimentation.
An ELF object file containing DWARF debug information can be augmented
with BTF debug information using pahole -J. pahole is part of dwarves.
These patches contribute:
- a BTF parser / BTF graph builder
- code to dump BTF information as it is parsed
- a BTF graph difference algorithm to generate graphs of differences
- a C type name generator
- code to serialise a difference graph as a text report
The graph difference algorithm uses a strongly-connected component
finder based on the path-based SCC algorithm. My main contribution
here was the design which allows the BTF graph difference algorithm to
be written in a straightforward recursive style.
Missing from these patches are:
- Some documentation I wrote in markdown format.
- A suite of small tests, of which the C language ones have been used to
validate the BTF utilities.
I hope this work will be useful to anyone wishing to experiment with
BTF as an ABI representation or who has an interest in graph diff
algorithms.
Feedback is very welcome.
Regards,
Giuliano.
Giuliano Procida (6):
Tweak clang-format
Allow C++17 code to be compiled
BTF: add SCC finder and test
BTF: add core functionality
BTF: add btfinfo and btfdiff tools
BTF: clang-format all the new source files
.clang-format | 9 +-
COMPILING | 5 +
configure.ac | 21 +-
include/abg-btf.h | 888 ++++++++++++++++++++++++
include/abg-scc.h | 122 ++++
src/Makefile.am | 9 +-
src/abg-btf.cc | 1649 +++++++++++++++++++++++++++++++++++++++++++++
tests/Makefile.am | 7 +
tests/test-scc.cc | 220 ++++++
tools/Makefile.am | 14 +
tools/btfdiff.cc | 71 ++
tools/btfinfo.cc | 22 +
12 files changed, 3034 insertions(+), 3 deletions(-)
create mode 100644 include/abg-btf.h
create mode 100644 include/abg-scc.h
create mode 100644 src/abg-btf.cc
create mode 100644 tests/test-scc.cc
create mode 100644 tools/btfdiff.cc
create mode 100644 tools/btfinfo.cc
--
2.32.0.272.g935e593368-goog
^ permalink raw reply [flat|nested] 14+ messages in thread* [PATCH 1/6] Tweak clang-format 2021-06-11 15:33 [PATCH 0/6] BTF ABI Giuliano Procida @ 2021-06-11 15:33 ` Giuliano Procida 2021-06-11 15:33 ` [PATCH 2/6] Allow C++17 code to be compiled Giuliano Procida ` (5 subsequent siblings) 6 siblings, 0 replies; 14+ messages in thread From: Giuliano Procida @ 2021-06-11 15:33 UTC (permalink / raw) To: libabigail; +Cc: dodji, kernel-team, gprocida, maennich, teguiani The BTF / SCC code is being migrated out of Google source control into AOSP. This comes with the opportunity to migrate the style to be closer libabigail's. In the first instance it makes sense to just reformat it with clang-format. I've updated this as follows. AlignConsecutiveDeclarations: false - as this is closer on average to libgabigail code and looks nicer for the new code anyway AllowShort*: (true) - these in theory should make things closer to libabigail style but in practice don't appear make any difference Cpp11BracedListStyle: true - this seems to improve some initialiser syntax BinPackArguments: false - we already turn this off for parameters SpaceAfterCStyleCast: true - seems to be the libabigail style * .clang-format: Various tweaks for new BTF code. Signed-off-by: Giuliano Procida <gprocida@google.com> --- .clang-format | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/.clang-format b/.clang-format index 1b422dfb..d09d739a 100644 --- a/.clang-format +++ b/.clang-format @@ -2,17 +2,24 @@ --- BasedOnStyle: GNU Standard: c++11 -AlignConsecutiveDeclarations: true +AlignConsecutiveDeclarations: false +AllowShortBlocksOnASingleLine: Always +AllowShortEnumsOnASingleLine: true +AllowShortFunctionsOnASingleLine: All +AllowShortLambdasOnASingleLine: All AlwaysBreakAfterReturnType: All BreakConstructorInitializers: BeforeColon ConstructorInitializerAllOnOneLineOrOnePerLine: true ConstructorInitializerIndentWidth: 2 +Cpp11BracedListStyle: true IndentWidth: 2 AlignAfterOpenBracket: Align +BinPackArguments: false BinPackParameters: false BreakStringLiterals: false PointerAlignment: Left SortUsingDeclarations: false +SpaceAfterCStyleCast: true SpaceBeforeParens: ControlStatements TabWidth: 8 UseTab: Always -- 2.32.0.272.g935e593368-goog ^ permalink raw reply [flat|nested] 14+ messages in thread
* [PATCH 2/6] Allow C++17 code to be compiled 2021-06-11 15:33 [PATCH 0/6] BTF ABI Giuliano Procida 2021-06-11 15:33 ` [PATCH 1/6] Tweak clang-format Giuliano Procida @ 2021-06-11 15:33 ` Giuliano Procida 2021-06-11 15:33 ` [PATCH 3/6] BTF: add SCC finder and test Giuliano Procida ` (4 subsequent siblings) 6 siblings, 0 replies; 14+ messages in thread From: Giuliano Procida @ 2021-06-11 15:33 UTC (permalink / raw) To: libabigail; +Cc: dodji, kernel-team, gprocida, maennich, teguiani The BTF code was developed in a C++17 environment. To ease integration here, allow C++17 to be enabled at configuration time. * configure.ac: Add --enable-cxx17 option defaulting to no. Signed-off-by: Giuliano Procida <gprocida@google.com> --- configure.ac | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/configure.ac b/configure.ac index 735cc9de..edd03cf8 100644 --- a/configure.ac +++ b/configure.ac @@ -138,6 +138,12 @@ AC_ARG_ENABLE(ubsan, ENABLE_UBSAN=$enableval, ENABLE_UBSAN=no) +AC_ARG_ENABLE(cxx17, + AS_HELP_STRING([--enable-cxx17=yes|no], + [enable features that use the C++17 compiler]), + ENABLE_CXX17=$enableval, + ENABLE_CXX17=no) + dnl ************************************************* dnl check for dependencies dnl ************************************************* @@ -153,7 +159,7 @@ AC_LANG([C++]) AC_LANG_COMPILER_REQUIRE dnl -dnl We use C++11 +dnl We use C++11 or C++17 if enabled dnl CXX_STANDARD=c++11 @@ -591,6 +597,12 @@ AX_VALGRIND_DFLT(sgcheck, off) AX_VALGRIND_CHECK +dnl Handle conditional use of a C++17 compiler +if test x$ENABLE_CXX17 = xyes; then + CXX_STANDARD=c++17 +fi +AM_CONDITIONAL(ENABLE_CXX17, test x$ENABLE_CXX17 = xyes) + dnl Set the list of libraries libabigail depends on DEPS_LIBS="$XML_LIBS $ELF_LIBS $DW_LIBS" -- 2.32.0.272.g935e593368-goog ^ permalink raw reply [flat|nested] 14+ messages in thread
* [PATCH 3/6] BTF: add SCC finder and test 2021-06-11 15:33 [PATCH 0/6] BTF ABI Giuliano Procida 2021-06-11 15:33 ` [PATCH 1/6] Tweak clang-format Giuliano Procida 2021-06-11 15:33 ` [PATCH 2/6] Allow C++17 code to be compiled Giuliano Procida @ 2021-06-11 15:33 ` Giuliano Procida 2021-06-11 15:33 ` [PATCH 4/6] BTF: add core functionality Giuliano Procida ` (3 subsequent siblings) 6 siblings, 0 replies; 14+ messages in thread From: Giuliano Procida @ 2021-06-11 15:33 UTC (permalink / raw) To: libabigail; +Cc: dodji, kernel-team, gprocida, maennich, teguiani The files are almost a straight copy of the originals. Changes: - Files renamed and #includes updated. - Header guards and include order are now in libabigail style. * include/abg-scc.h (SCC): New class to find SCCs. * tests/test-scc.cc: SCC test with randomly-generated graphs. * tests/Makefile.am: Add SCC test, conditional on C++17. Signed-off-by: Giuliano Procida <gprocida@google.com> --- include/abg-scc.h | 111 ++++++++++++++++++++++++++++ tests/Makefile.am | 7 ++ tests/test-scc.cc | 183 ++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 301 insertions(+) create mode 100644 include/abg-scc.h create mode 100644 tests/test-scc.cc diff --git a/include/abg-scc.h b/include/abg-scc.h new file mode 100644 index 00000000..d60b1aed --- /dev/null +++ b/include/abg-scc.h @@ -0,0 +1,111 @@ +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// -*- mode: C++ -*- +// +// Copyright (C) 2020 Google, Inc. +// +// Author: Giuliano Procida + +#ifndef __ABG_SCC_H__ +#define __ABG_SCC_H__ + +#include <cassert> +#include <cstdint> +#include <functional> +#include <optional> +#include <vector> + +namespace abigail { + +/* + * This is a streamlined Strongly-Connected Component finder for use with + * procedurally generated or explored graphs, where the nodes and edges are not + * known a priori. + * + * REQUIREMENTS + * + * The Node type must be copyable and the user must supply a well-behaved + * comparison function (allowing arbitrary data to accompany each node). + * + * The user code must take the form of a Depth First Search which can be + * repeatedly invoked on unvisited nodes until the whole graph has been + * traversed. + * + * The user code must ensure that nodes are not revisited once they have been + * assigned to an SCC. The finder does not maintain any state for such nodes. + * + * GUARANTEES + * + * Each node will be examined exactly once. + * + * The SCCs will be presented in a topological order, leaves first. + * + * Note that within each SCC, nodes will be presented in DFS traversal order, + * roots first. However, this is just an implemention detail, not a guarantee. + * + * USAGE + * + * Before examining a node, check it's not been visited already and then call + * Open. If the node is already "open" (i.e., is already waiting to be assigned + * to an SCC), this will return an empty optional value and the node should not + * be examined. If Open succeeds, a numerical node handle will be returned and + * the node will be recorded as waiting to be assigned to an SCC. + * + * Now examine the node, making recursive calls to follow edges to other nodes. + * + * Once the examination is done, call Close, passing in the handle and + * optionally a function to update data associated with the node. If the node + * has been identified as the "root" of an SCC, the whole SCC will be returned + * as a vector of nodes. If any processing needs to be done (such as recording + * the nodes as visited), this should be done now. Otherwise, an empty vector + * will be returned. + */ +template<typename Node> class SCC { + public: + explicit SCC(std::function<bool(const Node &, const Node &)> cmp) : cmp_(cmp) + {} + ~SCC() { + assert(open_.empty()); + assert(root_index_.empty()); + } + + std::optional<size_t> Open(const Node &node) { + for (size_t ix = 0; ix < open_.size(); ++ix) { + const auto &other = open_[ix]; + // node == other? + if (!cmp_(node, other) && !cmp_(other, node)) { + // Pop indices to nodes which cannot be the root of their SCC. + while (root_index_.back() > ix) + root_index_.pop_back(); + return {}; + } + } + // Unvisited, mark node as open and record root index. + auto ix = open_.size(); + open_.push_back(node); + root_index_.push_back(ix); + return ix; + } + + std::vector<Node> Close( + size_t ix, std::function<void(Node &)> update = [](Node &){}) { + std::vector<Node> scc; + assert(ix < open_.size()); + update(open_[ix]); + if (ix == root_index_.back()) { + // Close SCC. + root_index_.pop_back(); + std::move(open_.begin() + ix, open_.end(), std::back_inserter(scc)); + open_.resize(ix); + } + return scc; + } + + private: + std::function<bool(const Node &, const Node &)> cmp_; + std::vector<Node> open_; + std::vector<size_t> root_index_; +}; + +} // namespace abigail + +#endif // __ABG_SCC_H__ diff --git a/tests/Makefile.am b/tests/Makefile.am index 7a3a1f98..95df9542 100644 --- a/tests/Makefile.am +++ b/tests/Makefile.am @@ -53,6 +53,10 @@ else TESTS += runtestdefaultsupprs.py endif +if ENABLE_CXX17 +TESTS += runtestscc +endif + EXTRA_DIST = \ runtestcanonicalizetypes.sh.in \ runtestfedabipkgdiff.py.in \ @@ -166,6 +170,9 @@ testdiff2_LDADD=$(top_builddir)/src/libabigail.la printdifftree_SOURCES = print-diff-tree.cc printdifftree_LDADD = $(top_builddir)/src/libabigail.la +runtestscc_SOURCES = test-scc.cc +runtestscc_LDADD = libcatch.la + runtestslowselfcompare_sh_SOURCES = runtestslowselfcompare.sh$(EXEEXT): diff --git a/tests/test-scc.cc b/tests/test-scc.cc new file mode 100644 index 00000000..ccabb471 --- /dev/null +++ b/tests/test-scc.cc @@ -0,0 +1,183 @@ +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// -*- mode: C++ -*- +// +// Copyright (C) 2020 Google, Inc. +// +// Author: Giuliano Procida + +#include <algorithm> +#include <array> +#include <cmath> +#include <iostream> +#include <map> +#include <random> +#include <set> +#include <sstream> +#include <vector> + +#include "lib/catch.hpp" + +#include "abg-scc.h" + +namespace Test { + +using abigail::SCC; + +// Nodes are [0, N), the sets are the out-edges. +typedef std::vector<std::set<size_t>> Graph; + +std::ostream &operator<<(std::ostream &os, const Graph &g) { + for (size_t i = 0; i < g.size(); ++i) { + os << i << ':'; + for (auto o : g[i]) + os << ' ' << o; + os << '\n'; + } + return os; +} + +template<typename G> Graph invent(size_t n, G& gen) { + Graph graph(n); + std::uniform_int_distribution<int> toss(0, 1); + for (auto &node : graph) { + for (size_t o = 0; o < n; ++o) { + if (toss(gen)) + node.insert(o); + } + } + return graph; +} + +// Generate a graph g' where a -> b iff a and b are strongly connected in g. +Graph symmetric_subset_of_reflexive_transitive_closure(Graph g) { + const size_t n = g.size(); + // transitive closure using Floyd-Warshall + for (size_t o = 0; o < n; ++o) + g[o].insert(o); + for (size_t k = 0; k < n; ++k) { + for (size_t i = 0; i < n; ++i) { + for (size_t j = 0; j < n; ++j) { + if (!g[i].count(j) && g[i].count(k) && g[k].count(j)) + g[i].insert(j); + } + } + } + // now a -> b iff a has path to b in g + for (size_t i = 0; i < n; ++i) { + for (size_t j = i + 1; j < n; ++j) { + // discard a -> b if not b -> a and vice versa + auto ij = g[i].count(j); + auto ji = g[j].count(i); + if (ij < ji) g[j].erase(i); + if (ji < ij) g[i].erase(j); + } + } + // now have a -> b iff a has path to b and b has path to a in g + return g; +} + +// Generate a graph where a -> b iff a and b are in the same SCC. +Graph scc_strong_connectivity(const std::vector<std::set<size_t>> &sccs) { + size_t n = 0; + std::map<size_t, const std::set<size_t> *> edges; + for (const auto &scc : sccs) { + for (auto o : scc) { + if (o >= n) + n = o + 1; + edges[o] = &scc; + } + } + Graph g(n); + for (size_t o = 0; o < n; ++o) + g[o] = *edges[o]; + return g; +} + +void dfs(std::set<size_t> &visited, SCC<size_t> &scc, + const Graph &g, size_t node, + std::vector<std::set<size_t>> &sccs) { + if (visited.count(node)) + return; + auto handle = scc.Open(node); + if (!handle) + return; + for (auto o : g[node]) + dfs(visited, scc, g, o, sccs); + auto nodes = scc.Close(handle.value()); + if (!nodes.empty()) { + std::set<size_t> scc_set; + for (auto o : nodes) { + CHECK(visited.insert(o).second); + CHECK(scc_set.insert(o).second); + } + sccs.push_back(scc_set); + } +} + +void process(const Graph &g) { + const size_t n = g.size(); + + // find SCCs + std::set<size_t> visited; + SCC<size_t> scc{std::less<size_t>()}; + std::vector<std::set<size_t>> sccs; + for (size_t o = 0; o < n; ++o) + dfs(visited, scc, g, o, sccs); + + // check partition and topological order properties + std::set<size_t> seen; + for (const auto &nodes : sccs) { + CHECK(!nodes.empty()); + for (auto node : nodes) { + // value in range [0, n) + CHECK(node < n); + // value seen at most once + CHECK(seen.insert(node).second); + } + for (auto node : nodes) { + for (auto o : g[node]) { + // edges point to nodes in this or earlier SCCs + CHECK(seen.count(o)); + } + } + } + // exactly n values seen + CHECK(seen.size() == n); + + // check strong connectivity + auto g_scc_closure = scc_strong_connectivity(sccs); + auto g_closure = symmetric_subset_of_reflexive_transitive_closure(g); + // catch isn't printing nicely + if (g_scc_closure != g_closure) { + std::cerr << "original:\n" << g + << "SCC finder:\n" << g_scc_closure + << "SCCs independently:\n" << g_closure; + } + CHECK(g_scc_closure == g_closure); +} + +TEST_CASE("randomly-generated graphs") { + std::mt19937 gen; + auto seed = gen(); + // NOTES: + // Graphs of size 6 are plenty big enough to shake out bugs. + // There are O(2^k^2) possible directed graphs of size k. + // Testing costs are O(k^3) so we restrict accordingly. + uint64_t budget = 10000; + for (size_t k = 0; k < 7; ++k) { + uint64_t count = std::min(static_cast<uint64_t>(1) << (k*k), + budget / (k ? k * k * k : 1)); + INFO("testing with " << count << " graphs of size " << k); + for (uint64_t n = 0; n < count; ++n, ++seed) { + gen.seed(seed); + Graph g = invent(k, gen); + std::ostringstream os; + os << "a graph of " << k << " nodes generated using seed " << seed; + GIVEN(os.str()) { + process(g); + } + } + } +} + +} // namespace Test -- 2.32.0.272.g935e593368-goog ^ permalink raw reply [flat|nested] 14+ messages in thread
* [PATCH 4/6] BTF: add core functionality 2021-06-11 15:33 [PATCH 0/6] BTF ABI Giuliano Procida ` (2 preceding siblings ...) 2021-06-11 15:33 ` [PATCH 3/6] BTF: add SCC finder and test Giuliano Procida @ 2021-06-11 15:33 ` Giuliano Procida 2021-06-11 15:33 ` [PATCH 5/6] BTF: add btfinfo and btfdiff tools Giuliano Procida ` (2 subsequent siblings) 6 siblings, 0 replies; 14+ messages in thread From: Giuliano Procida @ 2021-06-11 15:33 UTC (permalink / raw) To: libabigail Cc: dodji, kernel-team, gprocida, maennich, teguiani, Maria Teguiani This commit adds core BTF functionality. The code can: - read ELF symbols using the symtab_reader - read BTF into a graph of type and symbol information - optionally perform a text dump of BTF as it's read - compute diffs between two BTF graphs as a diff graph - done using DFS and with the help of the SCC finder - create and cache full names for types - serialise a diff graph as a textual diff report - done using DFS The files are almost a straight copy of the originals. Changes: - Files renamed and #includes updated. - Header guards and include order are now in libabigail style. * COMPILING: Add note about BTF dependency. * configure.ac: Add check for <linux/btf.h>. * src/Makefile.am: Add abg-btf.cc, conditional on C++17 and presence of <linux/btf.h>. * include/abg-btf.h: New file. * src/abg-btf.cc: New file. Co-authored-by: Maria Teguiani <teguiani@google.com> Signed-off-by: Giuliano Procida <gprocida@google.com> --- COMPILING | 5 + configure.ac | 7 + include/abg-btf.h | 551 ++++++++++++++++++ src/Makefile.am | 9 +- src/abg-btf.cc | 1364 +++++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 1935 insertions(+), 1 deletion(-) create mode 100644 include/abg-btf.h create mode 100644 src/abg-btf.cc diff --git a/COMPILING b/COMPILING index 33613a37..75a6588a 100644 --- a/COMPILING +++ b/COMPILING @@ -5,6 +5,11 @@ the moment the dependencies are the following Free Software packages: libtool libxml2 +To build the BTF tools, you will need <linux/btf.h> which can be found +in the development package of: + + linux-libc + If you are building from the Git repository, then you'd also need the following packages: diff --git a/configure.ac b/configure.ac index edd03cf8..d9125d99 100644 --- a/configure.ac +++ b/configure.ac @@ -603,6 +603,13 @@ if test x$ENABLE_CXX17 = xyes; then fi AM_CONDITIONAL(ENABLE_CXX17, test x$ENABLE_CXX17 = xyes) +dnl Check for the presence of the BTF header. +HAVE_BTF=no +AC_CHECK_HEADER([linux/btf.h], + [HAVE_BTF=yes], + [AC_MSG_NOTICE([No linux/btf.h found, omitted BTF support.])]) +AM_CONDITIONAL(HAVE_BTF, test x$HAVE_BTF = xyes) + dnl Set the list of libraries libabigail depends on DEPS_LIBS="$XML_LIBS $ELF_LIBS $DW_LIBS" diff --git a/include/abg-btf.h b/include/abg-btf.h new file mode 100644 index 00000000..d47b4ac9 --- /dev/null +++ b/include/abg-btf.h @@ -0,0 +1,551 @@ +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// -*- mode: C++ -*- +// +// Copyright (C) 2020-2021 Google, Inc. +// +// Author: Maria Teguiani +// Author: Giuliano Procida + +#ifndef __ABG_BTF_H__ +#define __ABG_BTF_H__ + +#include <fcntl.h> +#include <linux/btf.h> + +#include <cstdint> +#include <cstdlib> +#include <iostream> +#include <map> +#include <set> +#include <sstream> +#include <string> +#include <string_view> +#include <unordered_map> +#include <vector> + +#include "abg-ir.h" +#include "abg-scc.h" + +namespace abigail { +namespace btf { + +#define m_assert(expr, msg) assert(((void)(msg), (expr))) + +using Kind = uint32_t; + +// A Member refers to a data element of a struct or union, used in the context +// of StructUnion +struct Member { + uint32_t typeId_; + uint32_t offset_; + uint32_t bitfieldSize_; +}; + +// A Parameter refers to a variable declared in the function declaration, used +// in the context of Function +struct Parameter { + std::string name_; + uint32_t typeId_; +}; + +struct Secinfo { + uint32_t typeId_; + uint32_t offset_; + uint32_t bytesize_; +}; + +enum class ForwardDeclarationKind { STRUCT, UNION }; + +std::ostream &operator<<(std::ostream &os, ForwardDeclarationKind kind); + +class Type; + +using Comparison = std::pair<const Type *, const Type *>; + +enum class Precedence { NIL, POINTER, ARRAY_FUNCTION, ATOMIC }; +enum class Side { LEFT, RIGHT }; + +class Name { + public: + explicit Name(std::string_view name) + : left_(name), precedence_(Precedence::NIL), right_() {} + Name(std::string_view left, Precedence precedence, std::string_view right) + : left_(left), precedence_(precedence), right_(right) {} + Name Add(Side side, Precedence precedence, std::string_view text) const; + Name Qualify(const std::set<Kind> &qualifiers) const; + std::ostream &Print(std::ostream &os) const; + + private: + std::string left_; + Precedence precedence_; + std::string right_; +}; + +std::ostream &operator<<(std::ostream &os, const Name &name); + +using NameCache = std::unordered_map<const Type *, Name>; + +struct DiffDetail { + DiffDetail(const std::string &text, const std::optional<Comparison> &edge) + : text_(text), edge_(edge) {} + std::string text_; + std::optional<Comparison> edge_; +}; + +using Diff = std::vector<DiffDetail>; + +struct Result { + void AddDiff(const std::string &text) { + equals_ = false; + details_.emplace_back(text, std::optional<Comparison>()); + } + + void AddDiff(const std::string &text, Comparison comparison) { + equals_ = false; + details_.emplace_back(text, comparison); + } + + void MaybeAddDiff(const std::string &text, + const std::pair<bool, std::optional<Comparison>> &p) { + equals_ &= p.first; + const auto &diff = p.second; + if (diff) + details_.emplace_back(text, diff); + } + + // Maximally powerful lazy version, takes a function that outputs an "edge" + // diff description, to be used only when a diff is present. + void MaybeAddDiff(std::function<void(std::ostream &)> text, + const std::pair<bool, std::optional<Comparison>> &p) { + equals_ &= p.first; + const auto &diff = p.second; + if (diff) { + std::ostringstream os; + text(os); + details_.emplace_back(os.str(), diff); + } + } + + template<typename T> void MaybeAddDiff( + const std::string &text, const T &before, const T &after) { + if (before != after) { + equals_ = false; + std::ostringstream os; + os << text << " changed from " << before << " to " << after; + AddDiff(os.str()); + } + } + + // Lazy version. + template<typename T> void MaybeAddDiff( + std::function<void(std::ostream &)> text, + const T &before, const T &after) { + if (before != after) { + equals_ = false; + std::ostringstream os; + text(os); + os << " changed from " << before << " to " << after; + AddDiff(os.str()); + } + } + + bool equals_ = true; + Diff details_; +}; + +using Outcomes = std::map<Comparison, Diff>; +// unvisited (absent) -> started (false) -> finished (true) +using Seen = std::map<Comparison, bool>; + +void Print(const Comparison &comparison, const Outcomes &outcomes, Seen &seen, + NameCache &names, std::ostream &os, size_t indent = 0); + +void Print(const Diff &details, const Outcomes &outcomes, Seen &seen, + NameCache &names, std::ostream &os, size_t indent = 0); + +class Type { + public: + Type(const std::vector<std::unique_ptr<Type>> &types, uint32_t index, + std::string_view name, Kind kind) + : types_(types), index_(index), name_(name), kind_(kind) {} + virtual ~Type() = default; + uint32_t GetIndex() const { return index_; } + std::string_view GetName() const { return name_; } + Kind GetKind() const { return kind_; } + const std::vector<std::unique_ptr<Type>> &GetTypes() const { + return types_; + } + + // as<Type>() provides a method to defer downcasting to the base class, + // instead of needing to use dynamic_cast in a local context. If the type is + // not correct, the assert will trigger in debug mode. In release mode, this + // will crash dereferencing the nullptr. + template <typename Target> + const Target &as() const { + static_assert(std::is_convertible<Target *, Type *>::value, + "Target must publically inherit Type"); + const Target *t = dynamic_cast<const Target *>(this); + m_assert(t, "Invalid downcast"); + return *t; + } + // Separate qualifiers from underlying type. + // + // The caller must always be prepared to receive a different type as + // qualifiers are sometimes discarded. + virtual const Type &ResolveQualifiers(std::set<Kind> &qualifiers) const; + virtual const Type &ResolveTypedef( + std::vector<std::string_view> &typedefs) const; + + const Name &GetDescription(NameCache &names) const; + static Result CompareSymbols( + const std::map<std::string_view, const Type *const> &lhs, + const std::map<std::string_view, const Type *const> &rhs, + Outcomes &outcomes); + + protected: + struct State { + explicit State(Outcomes &o) : outcomes(o), scc(o.value_comp()) { } + Outcomes &outcomes; + std::set<Comparison> known_equal; + SCC<Outcomes::value_type> scc; + }; + const Type &GetTypeAtIndex(size_t index) const; + + virtual Name MakeDescription(NameCache &names) const = 0; + virtual Result Equals(const Type &other, State &state) const = 0; + static Comparison Removed(const Type &lhs, State &state); + static Comparison Added(const Type &rhs, State &state); + static std::pair<bool, std::optional<Comparison>> Compare( + const Type &lhs, const Type &rhs, State &state); + + private: + static std::string GetDiffMessage(NameCache &names, + const Type &lhs, const Type &rhs, + const std::string &message = std::string()); + const std::vector<std::unique_ptr<Type>> &types_; + const uint32_t index_; + const std::string name_; + const Kind kind_; +}; + +class Void : public Type { + public: + Void(const std::vector<std::unique_ptr<Type>> &types, uint32_t index, + std::string_view name, Kind kind) + : Type(types, index, name, kind) {} + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; +}; + +class Ptr : public Type { + public: + Ptr(const std::vector<std::unique_ptr<Type>> &types, uint32_t index, + std::string_view name, Kind kind, uint32_t pointeeTypeId) + : Type(types, index, name, kind), + pointeeTypeId_(pointeeTypeId) {} + uint32_t GetPointeeTypeId() const { return pointeeTypeId_; } + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; + + private: + const uint32_t pointeeTypeId_; +}; + +class Typedef : public Type { + public: + Typedef(const std::vector<std::unique_ptr<Type>> &types, uint32_t index, + std::string_view name, Kind kind, uint32_t referredTypeId) + : Type(types, index, name, kind), + referredTypeId_(referredTypeId) {} + uint32_t GetReferredTypeId() const { return referredTypeId_; } + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; + const Type &ResolveTypedef( + std::vector<std::string_view> &typedefs) const final; + + private: + const uint32_t referredTypeId_; +}; + +class Qualifier : public Type { + public: + Qualifier(const std::vector<std::unique_ptr<Type>> &types, + uint32_t index, std::string_view name, Kind kind, + uint32_t qualifiedTypeId) + : Type(types, index, name, kind), + qualifiedTypeId_(qualifiedTypeId) {} + uint32_t GetQualifiedTypeId() const { return qualifiedTypeId_; } + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; + const Type &ResolveQualifiers(std::set<Kind> &qualifiers) const final; + + private: + const uint32_t qualifiedTypeId_; +}; + +class Integer : public Type { + public: + Integer(const std::vector<std::unique_ptr<Type>> &types, uint32_t index, + std::string_view name, Kind kind, uint32_t encoding, + uint32_t offset, uint32_t bitsize, uint32_t bytesize) + : Type(types, index, name, kind), + offset_(offset), + bitsize_(bitsize), + bytesize_(bytesize), + isBool_(encoding & BTF_INT_BOOL), + isSigned_(encoding & BTF_INT_SIGNED), + isChar_(encoding & BTF_INT_CHAR) {} + bool isBool() const { return isBool_; } + bool isSigned() const { return isSigned_; } + bool isChar() const { return isChar_; } + uint32_t GetOffset() const { return offset_; } + + // GetBitSize() gives the semantics of the field. GetByteSize() gives the + // storage size, and is equal or greater than GetBitSize()*8 + uint32_t GetBitSize() const { return bitsize_; } + uint32_t GetByteSize() const { return bytesize_; } + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; + + private: + const uint32_t offset_; + const uint32_t bitsize_; + const uint32_t bytesize_; + const bool isBool_; + const bool isSigned_; + const bool isChar_; +}; + +class Array : public Type { + public: + Array(const std::vector<std::unique_ptr<Type>> &types, uint32_t index, + std::string_view name, Kind kind, uint32_t elementTypeId, + uint32_t indexTypeId, uint32_t numOfElements) + : Type(types, index, name, kind), + elementTypeId_(elementTypeId), + indexTypeId_(indexTypeId), + numOfElements_(numOfElements) {} + uint32_t GetElementTypeId() const { return elementTypeId_; } + uint32_t GetIndexTypeId() const { return indexTypeId_; } + uint32_t GetNumberOfElements() const { return numOfElements_; } + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; + + private: + const uint32_t elementTypeId_; + const uint32_t indexTypeId_; + const uint32_t numOfElements_; +}; + +class StructUnion : public Type { + public: + StructUnion(const std::vector<std::unique_ptr<Type>> &types, + uint32_t index, std::string_view name, Kind kind, + uint32_t bytesize, std::map<std::string, Member> members) + : Type(types, index, name, kind), + bytesize_(bytesize), + members_(members) {} + uint32_t GetByteSize() const { return bytesize_; } + const std::map<std::string, Member> &GetMembers() const { return members_; } + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; + + private: + const uint32_t bytesize_; + const std::map<std::string, Member> members_; +}; + +class Enumeration : public Type { + public: + Enumeration(const std::vector<std::unique_ptr<Type>> &types, + uint32_t index, std::string_view name, Kind kind, + uint32_t bytesize, std::map<std::string, int> enumerators) + : Type(types, index, name, kind), + bytesize_(bytesize), + enumerators_(enumerators) {} + uint32_t GetByteSize() const { return bytesize_; } + const std::map<std::string, int> &GetEnums() const { return enumerators_; } + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; + + private: + const uint32_t bytesize_; + const std::map<std::string, int> enumerators_; +}; + +// BTF only considers structs and unions as forward-declared types, and does not +// include forward-declared enums. They are treated as BTF_KIND_ENUMs with vlen +// set to zero +class ForwardDeclaration : public Type { + public: + ForwardDeclaration(const std::vector<std::unique_ptr<Type>> &types, + uint32_t index, std::string_view name, Kind kind, + bool isUnion) + : Type(types, index, name, kind), + fwdKind_(isUnion ? ForwardDeclarationKind::UNION + : ForwardDeclarationKind::STRUCT) {} + ForwardDeclarationKind GetFwdKind() const { return fwdKind_; } + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; + + private: + const ForwardDeclarationKind fwdKind_; +}; + +class Function : public Type { + public: + enum class Linkage : uint16_t { STATIC, GLOBAL, EXTERN }; + Function(const std::vector<std::unique_ptr<Type>> &types, + uint32_t index, std::string_view name, Kind kind, + uint32_t referredTypeId, Linkage linkage) + : Type(types, index, name, kind), + referredTypeId_(referredTypeId), + linkage_(linkage) {} + uint32_t GetReferredTypeId() const { return referredTypeId_; } + Linkage GetLinkage() const { return linkage_; } + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; + + private: + const uint32_t referredTypeId_; + const Linkage linkage_; +}; + +class FunctionPrototype : public Type { + public: + FunctionPrototype(const std::vector<std::unique_ptr<Type>> &types, + uint32_t index, std::string_view name, Kind kind, + uint32_t returnTypeId, std::vector<Parameter> parameters) + : Type(types, index, name, kind), + returnTypeId_(returnTypeId), + parameters_(parameters) {} + uint32_t GetReturnTypeId() const { return returnTypeId_; } + const std::vector<Parameter> &GetParameters() const { return parameters_; } + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; + + private: + const uint32_t returnTypeId_; + const std::vector<Parameter> parameters_; +}; + +class Variable : public Type { + public: + enum class Linkage : uint32_t { STATIC, GLOBAL_ALLOC, GLOBAL_EXTERN }; + Variable(const std::vector<std::unique_ptr<Type>> &types, + uint32_t index, std::string_view name, Kind kind, + unsigned varTypeId, Linkage linkage) + : Type(types, index, name, kind), + varTypeId_(varTypeId), + linkage_(linkage) {} + uint32_t GetVarTypeId() const { return varTypeId_; } + Linkage GetLinkage() const { return linkage_; } + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; + + private: + const uint32_t varTypeId_; + const Linkage linkage_; +}; + +class DataSection : public Type { + public: + DataSection(const std::vector<std::unique_ptr<Type>> &types, + uint32_t index, std::string_view name, Kind kind, + uint32_t bytesize, std::vector<Secinfo> secinfos) + : Type(types, index, name, kind), + bytesize_(bytesize), + secinfos_(secinfos) {} + uint32_t GetByteSize() const { return bytesize_; } + const std::vector<Secinfo> &GetSecinfos() const { return secinfos_; } + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; + + private: + const uint32_t bytesize_; + const std::vector<Secinfo> secinfos_; +}; + +// Not actually a BTF type but needed for uniformity of representation. +class ElfSymbol : public Type { + public: + ElfSymbol(const std::vector<std::unique_ptr<Type>> &types, + abigail::elf_symbol_sptr symbol, uint32_t type_id) + : Type(types, -1, {}, -1), symbol_(symbol), type_id_(type_id) {} + abigail::elf_symbol_sptr GetElfSymbol() const { return symbol_; } + uint32_t GetTypeId() const { return type_id_; } + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; + + private: + abigail::elf_symbol_sptr symbol_; + uint32_t type_id_; +}; + +std::ostream &operator<<(std::ostream &os, const Type &bt); +std::ostream &operator<<(std::ostream &os, const Ptr &bp); +std::ostream &operator<<(std::ostream &os, const Typedef &bp); +std::ostream &operator<<(std::ostream &os, const Qualifier &bp); +std::ostream &operator<<(std::ostream &os, const Integer &bi); +std::ostream &operator<<(std::ostream &os, const Array &ba); +std::ostream &operator<<(std::ostream &os, const StructUnion &bsu); +std::ostream &operator<<(std::ostream &os, const Enumeration &be); +std::ostream &operator<<(std::ostream &os, const ForwardDeclaration &bfd); +std::ostream &operator<<(std::ostream &os, const Function &bf); +std::ostream &operator<<(std::ostream &os, const FunctionPrototype &bfp); +std::ostream &operator<<(std::ostream &os, const Variable &bv); +std::ostream &operator<<(std::ostream &os, const DataSection &bds); +std::ostream &operator<<(std::ostream &os, const ElfSymbol &bes); +std::ostream &operator<<(std::ostream &os, Variable::Linkage linkage); +std::ostream &operator<<(std::ostream &os, Function::Linkage linkage); + +// BTF Specification: https://www.kernel.org/doc/html/latest/bpf/btf.html +class Structs { + public: + Structs(const char *start, std::unique_ptr<abigail::ir::environment> env, + const abigail::symtab_reader::symtab_sptr tab, + const bool verbose = false); + ~Structs() = default; + void PrintHeader(); + void BuildTypes(); + void PrintStringSection(); + const std::map<std::string_view, const Type *const> &GetSymbols( + bool use_elf_symbols) const { + return use_elf_symbols ? elf_symbols_ : btf_symbols_; + } + + private: + const btf_header *header_; + const btf_type *type_section_; + const char *str_section_; + const std::unique_ptr<abigail::ir::environment> env_; + const abigail::symtab_reader::symtab_sptr tab_; + const bool verbose_; + + std::vector<std::unique_ptr<Type>> types_; + std::unordered_map<std::string_view, uint32_t> btf_symbol_types_; + std::map<std::string_view, const Type *const> btf_symbols_; + std::map<std::string_view, const Type *const> elf_symbols_; + + std::vector<std::string> bad_names_; + std::string bad_prefix_1_; + std::string bad_prefix_2_; + + int BuildOneType(const btf_type *t, uint32_t index); + void BuildElfSymbols(); + std::map<std::string, Member> BuildMembers( + bool kflag, const btf_member *members, size_t vlen); + std::map<std::string, int> BuildEnums(const struct btf_enum *enums, + size_t vlen); + std::vector<Parameter> BuildParams(const struct btf_param *params, + size_t vlen); + std::vector<Secinfo> BuildDatasec(const btf_type *type, size_t vlen); + std::string_view GetName(uint32_t name_off); +}; + +Structs ReadFile(const std::string &path, bool verbose = false); + +} // end namespace btf +} // end namespace abigail + +#endif // __ABG_BTF_H__ diff --git a/src/Makefile.am b/src/Makefile.am index 430ce98d..d67c604c 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -8,6 +8,12 @@ VIZ_SOURCES = abg-viz-common.cc \ abg-viz-dot.cc \ abg-viz-svg.cc +if ENABLE_CXX17 +if HAVE_BTF + BTF_SOURCES = abg-btf.cc +endif +endif + libabigail_la_SOURCES = \ abg-internal.h \ abg-traverse.cc \ @@ -39,7 +45,8 @@ abg-elf-helpers.cc \ abg-regex.cc \ abg-symtab-reader.h \ abg-symtab-reader.cc \ -$(VIZ_SOURCES) +$(VIZ_SOURCES) \ +$(BTF_SOURCES) libabigail_la_LIBADD = $(DEPS_LIBS) libabigail_la_LDFLAGS = -lpthread -Wl,--as-needed -no-undefined diff --git a/src/abg-btf.cc b/src/abg-btf.cc new file mode 100644 index 00000000..8e4f9ea6 --- /dev/null +++ b/src/abg-btf.cc @@ -0,0 +1,1364 @@ +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// -*- mode: C++ -*- +// +// Copyright (C) 2020-2021 Google, Inc. +// +// Author: Maria Teguiani +// Author: Giuliano Procida + +#include <elfutils/libdwfl.h> + +#include <algorithm> +#include <array> +#include <iomanip> +#include <set> +#include <sstream> + +#include "abg-elf-helpers.h" +#include "abg-symtab-reader.h" +#include "abg-tools-utils.h" + +#include "abg-btf.h" + +namespace abigail { +namespace btf { + +// This is a helper map that yields the name of a Type in the preferred +// print style by indexing into the vector with a Kind +static constexpr std::array<std::string_view, 16> kKindNames = { + "void type", + "integer type", + "pointer type", + "array type", + "struct type", + "union type", + "enum type", + "forward declaration", + "typedef", + "volatile", + "const", + "restrict", + "function", + "function type", + "variable", + "data section" +}; + +// This matches bpftool dump format raw. +static constexpr std::array<std::string_view, 16> kRawKindNames = { + "VOID", + "INT", + "PTR", + "ARRAY", + "STRUCT", + "UNION", + "ENUM", + "FWD", + "TYPEDEF", + "VOLATILE", + "CONST", + "RESTRICT", + "FUNC", + "FUNC_PROTO", + "VAR", + "DATASEC" +}; + +static constexpr std::array<std::string_view, 3> kVarLinkage = { + "static", + "global-alloc", + "global-extern" // NOTE: bpftool currently says "(unknown)" +}; + +static constexpr std::array<std::string_view, 3> kFunLinkage = { + "static", + "global", + "extern" +}; + +Name Name::Add(Side side, Precedence precedence, std::string_view text) const { + bool bracket = precedence < precedence_; + std::ostringstream left; + std::ostringstream right; + + // Bits on the left need (sometimes) to be separated by whitespace. + left << left_; + if (bracket) + left << '('; + else if (side == Side::LEFT) + left << ' '; + + (side == Side::LEFT ? left : right) << text; + + // Bits on the right are arrays [] and functions () and need no whitespace. + if (bracket) + right << ')'; + right << right_; + + return Name{left.str(), precedence, right.str()}; +} + +Name Name::Qualify(const std::set<Kind> &qualifiers) const { + // this covers the case when bad qualifiers have been dropped + if (qualifiers.empty()) + return *this; + // add qualifiers to the left or right of the type stem + std::ostringstream os; + if (precedence_ == Precedence::NIL) { + for (const auto &qualifier : qualifiers) + os << kKindNames[qualifier] << ' '; + os << left_; + } else if (precedence_ == Precedence::POINTER) { + os << left_; + for (const auto &qualifier : qualifiers) + os << ' ' << kKindNames[qualifier]; + } else { + m_assert(false, "unqualifiable element"); + } + // qualifiers attach without affecting precedence + return Name{os.str(), precedence_, right_}; +} + +std::ostream &Name::Print(std::ostream &os) const { + return os << left_ << right_; +} + +std::ostream &operator<<(std::ostream &os, const Name &name) { + return name.Print(os); +} + +// There are several reasons for treating CV-qualifiers specially. +// 1. They upset the precedence scheme we've got going here. +// 2. Qualifiers need to be placed according to what they qualify. +// 3. The BTF model doesn't preclude ordering and duplication issues. +// 4. A better model would have qualifiers as part of the types. +const Name &Type::GetDescription(NameCache &names) const { + // infinite recursion prevention - insert at most once + static const Name black_hole{"#"}; + + auto insertion = names.insert({this, black_hole}); + Name &cached = insertion.first->second; + + if (insertion.second) { + // newly inserted, need to determine name of type + std::set<Kind> qualifiers; + const Type &under = ResolveQualifiers(qualifiers); + if (this == &under) { + // unqualified, simple case + cached = MakeDescription(names); + } else { + // qualified, but we may end up adding no qualifiers + auto insertion_under = names.insert({&under, black_hole}); + Name &cached_under = insertion_under.first->second; + + // newly inserted underlying type name + if (insertion_under.second) + cached_under = under.MakeDescription(names); + + // add the qualifiers (to the appropriate side) + cached = cached_under.Qualify(qualifiers); + } + } + + return cached; +} + +std::string GetPlainDescription(NameCache &names, const Type &type) { + std::ostringstream os; + os << '"' << type.GetDescription(names) << '"'; + return os.str(); +} + +std::string GetTypedefDescription(NameCache &names, const Type &given) { + std::ostringstream os; + std::vector<std::string_view> typedefs; + const Type &type = given.ResolveTypedef(typedefs); + for (auto td : typedefs) + os << std::quoted(td) << " = "; + os << GetPlainDescription(names, type); + return os.str(); +} + +constexpr size_t INDENT_INCREMENT = 2; + +void Print(const Comparison &comparison, const Outcomes &outcomes, Seen &seen, + NameCache &names, std::ostream &os, size_t indent) { + const auto *lhs = comparison.first; + const auto *rhs = comparison.second; + if (!rhs) { + os << GetPlainDescription(names, *lhs) << " was removed\n"; + return; + } + if (!lhs) { + os << GetPlainDescription(names, *rhs) << " was added\n"; + return; + } + bool td = lhs->GetKind() == BTF_KIND_TYPEDEF + || rhs->GetKind() == BTF_KIND_TYPEDEF; + const std::string lhs_descr = td ? GetTypedefDescription(names, *lhs) + : GetPlainDescription(names, *lhs); + const std::string rhs_descr = td ? GetTypedefDescription(names, *rhs) + : GetPlainDescription(names, *rhs); + if (lhs_descr == rhs_descr) + os << lhs_descr << " changed"; + else + os << "changed from " << lhs_descr << " to " << rhs_descr; + const auto &details = outcomes.find(comparison)->second; + auto insertion = seen.insert({comparison, false}); + if (!insertion.second) { + if (!insertion.first->second) + os << " (being reported)"; + else if (!details.empty()) + os << " (already reported)"; + } + os << '\n'; + if (insertion.second) { + Print(details, outcomes, seen, names, os, indent + INDENT_INCREMENT); + insertion.first->second = true; + } + // paragraph spacing + if (!indent) + os << '\n'; +} + +void Print(const Diff &details, const Outcomes &outcomes, Seen &seen, + NameCache &names, std::ostream &os, size_t indent) { + for (const auto &detail : details) { + os << std::string(indent, ' ') << detail.text_; + if (!detail.edge_) { + os << '\n'; + } else { + os << ' '; + Print(detail.edge_.value(), outcomes, seen, names, os, indent); + } + } +} + +const Type &Type::GetTypeAtIndex(size_t index) const { + m_assert(index < types_.size(), "Index out of bounds."); + return *(types_[index].get()); +} + +std::string QualifiersMessage(Kind qualifier, const std::string &action) { + std::ostringstream os; + os << "qualifier " << kKindNames[qualifier] << ' ' << action; + return os.str(); +} + +Result Type::CompareSymbols( + const std::map<std::string_view, const Type *const> &lhs, + const std::map<std::string_view, const Type *const> &rhs, + Outcomes &outcomes) { + Result result; + State state(outcomes); + auto lit = lhs.begin(); + auto rit = rhs.begin(); + // Each branch contains a NULL pointer check in case BTF information is + // missing for a symbol. We conservatively have to assume that any symbol + // without BTF information may have changed type. + // + // NOTE: this currently happens for all global variables + while (lit != lhs.end() || rit != rhs.end()) { + if (rit == rhs.end() || (lit != lhs.end() && lit->first < rit->first)) { + // removed + if (lit->second) { + auto diff = Removed(*lit->second, state); + result.AddDiff("symbol", diff); + } else { + std::ostringstream os; + os << "symbol " << std::quoted(lit->first) + << " (of unknown type) was removed"; + result.AddDiff(os.str()); + } + ++lit; + } else if (lit == lhs.end() || (rit != rhs.end() && lit->first > rit->first)) { + // added + if (rit->second) { + auto diff = Added(*rit->second, state); + result.AddDiff("symbol", diff); + } else { + std::ostringstream os; + os << "symbol " << std::quoted(rit->first) + << " (if unknown type) was added"; + result.AddDiff(os.str()); + } + ++rit; + } else { + // in both + if (lit->second && rit->second) { + auto diff = Compare(*lit->second, *rit->second, state); + result.MaybeAddDiff("symbol", diff); + } else { + std::ostringstream os; + os << "symbol " << std::quoted(lit->first) + << " (of unknown type) may have changed"; + result.AddDiff(os.str()); + } + ++lit; + ++rit; + } + } + return result; +} + +Comparison Type::Removed(const Type &lhs, State &state) { + Comparison comparison{&lhs, nullptr}; + state.outcomes.insert({comparison, {}}); + return comparison; +} + +Comparison Type::Added(const Type &rhs, State &state) { + Comparison comparison{nullptr, &rhs}; + state.outcomes.insert({comparison, {}}); + return comparison; +} + +/* + * We compute a diff for every visited node. + * + * Each node has one of: + * 1. equals = true; perhaps only tentative edge differences + * 2. equals = false; at least one definitive node or edge difference + * + * On the first visit to a node we can put a placeholder in, the equals value is + * irrelevant, the diff may contain local and edge differences. If an SCC + * contains only internal edge differences (and equivalently equals is true) + * then the differences can all (eventually) be discarded. + * + * On exit from the first visit to a node, equals reflects the tree of + * comparisons below that node in the DFS and similarly, the diff graph starting + * from the node contains a subtree of this tree plus potentially edges to + * existing nodes to the side or below (already visited SCCs, sharing), or above + * (back links forming cycles). + * + * When an SCC is closed, all equals implies deleting all diffs, any false + * implies updating all to false. + * + * On subsequent visits to a node, there are 2 cases. The node is still open: + * return true and an edge diff. The node is closed, return the stored value and + * an edge diff. + */ +std::pair<bool, std::optional<Comparison>> Type::Compare( + const Type &lhs, const Type &rhs, Type::State &state) { + Comparison comparison{&lhs, &rhs}; + + // 1. Check if the comparison has an already known result. + if (state.known_equal.count(comparison)) { + // Already visited and closed. Equal. + return {true, {}}; + } + if (state.outcomes.count(comparison)) { + // Already visited and closed. Different. + return {false, {comparison}}; + } + // Either open or not visited at all + + // 2. Record node with Strongly-Connected Component finder. + auto handle = state.scc.Open({comparison, {}}); + if (!handle) { + // Already open. + // + // Return a dummy true outcome and some tentative diffs. The diffs may end + // up not being used and, while it would be nice to be lazier, they encode + // all the cycling-breaking edges needed to recreate a full diff structure. + return {true, {comparison}}; + } + // Comparison opened, need to close it before returning. + + Result result; + + std::set<Kind> lhs_quals; + std::set<Kind> rhs_quals; + const Type &l = lhs.ResolveQualifiers(lhs_quals); + const Type &r = rhs.ResolveQualifiers(rhs_quals); + if (!lhs_quals.empty() || !rhs_quals.empty()) { + // 3.1 Qualified type difference. + auto lit = lhs_quals.begin(); + auto rit = rhs_quals.begin(); + auto lend = lhs_quals.end(); + auto rend = rhs_quals.end(); + while (lit != lend || rit != rend) { + if (rit == rend || (lit != lend && *lit < *rit)) { + result.AddDiff(QualifiersMessage(*lit, "removed")); + ++lit; + } else if (lit == lend || (rit != rend && *lit > *rit)) { + result.AddDiff(QualifiersMessage(*rit, "added")); + ++rit; + } else { + ++lit; + ++rit; + } + } + const auto comp = Compare(l, r, state); + result.MaybeAddDiff("underlying type", comp); + } else if (l.GetKind() == BTF_KIND_TYPEDEF + || r.GetKind() == BTF_KIND_TYPEDEF) { + // 3.2 Typedef difference. + std::vector<std::string_view> l_typedefs; + std::vector<std::string_view> r_typedefs; + const Type &l_ref = l.ResolveTypedef(l_typedefs); + const Type &r_ref = r.ResolveTypedef(r_typedefs); + const auto comp = Compare(l_ref, r_ref, state); + result.MaybeAddDiff("via typedefs", comp); + } else if (typeid(l) != typeid(r)) { + // 4. Incomparable. + result.equals_ = false; + } else { + // 5. Actually compare with dynamic type dispatch. + result = l.Equals(r, state); + } + + // 6. Update result and check for a complete Strongly-Connected Component. + auto comparisons = state.scc.Close(handle.value(), + [&result](Outcomes::value_type &p) { + p.second = result.details_; + }); + if (!comparisons.empty()) { + // Closed SCC. + // + // Note that result now incorporates every inequality and difference in the + // SCC via the DFS spanning tree. + if (result.equals_) { + // Same. Record equalities. + for (auto &c : comparisons) + state.known_equal.insert(c.first); + return {true, {}}; + } else { + // Different. Record diffs. + state.outcomes.insert(std::make_move_iterator(comparisons.begin()), + std::make_move_iterator(comparisons.end())); + } + } + + // Note that both equals and diff are tentative iff comparison is open. + return {result.equals_, {comparison}}; +} + +Name Void::MakeDescription(NameCache &names) const { + return Name{"void"}; +} + +Name Ptr::MakeDescription(NameCache &names) const { + return GetTypeAtIndex(GetPointeeTypeId()).GetDescription(names).Add( + Side::LEFT, Precedence::POINTER, "*"); +} + +Name Typedef::MakeDescription(NameCache &names) const { + return Name{GetName()}; +} + +Name Qualifier::MakeDescription(NameCache &names) const { + m_assert(false, "should not be called"); // NOLINT + return Name{GetName()}; +} + +Name Integer::MakeDescription(NameCache &names) const { + return Name{GetName()}; +} + +Name Array::MakeDescription(NameCache &names) const { + std::ostringstream os; + os << '[' << GetNumberOfElements() << ']'; + return GetTypeAtIndex(GetElementTypeId()).GetDescription(names).Add( + Side::RIGHT, Precedence::ARRAY_FUNCTION, os.str()); +} + +Name StructUnion::MakeDescription(NameCache &names) const { + std::ostringstream os; + os << (GetKind() == BTF_KIND_STRUCT ? "struct" : "union") + << ' ' << (GetName().empty() ? "<anon>" : GetName()); + return Name{os.str()}; +} + +Name Enumeration::MakeDescription(NameCache &names) const { + std::ostringstream os; + os << "enum " << (GetName().empty() ? "<anon>" : GetName()); + if (GetEnums().empty()) + os << "<incomplete>"; + return Name{os.str()}; +} + +Name ForwardDeclaration::MakeDescription(NameCache &names) const { + std::ostringstream os; + os << GetFwdKind() << ' ' << GetName() << "<incomplete>"; + return Name{os.str()}; +} + +Name FunctionPrototype::MakeDescription(NameCache &names) const { + std::ostringstream os; + os << '('; + bool sep = false; + for (const auto &p : GetParameters()) { + if (sep) + os << ", "; + else + sep = true; + const auto &arg_descr = GetTypeAtIndex(p.typeId_).GetDescription(names); + if (p.name_.empty()) + os << arg_descr; + else + os << arg_descr.Add(Side::LEFT, Precedence::ATOMIC, p.name_); + } + os << ')'; + return GetTypeAtIndex(GetReturnTypeId()).GetDescription(names).Add( + Side::RIGHT, Precedence::ARRAY_FUNCTION, os.str()); +} + +Name Variable::MakeDescription(NameCache &names) const { + return GetTypeAtIndex(GetVarTypeId()).GetDescription(names).Add( + Side::LEFT, Precedence::ATOMIC, GetName()); +} + +Name Function::MakeDescription(NameCache &names) const { + return GetTypeAtIndex(GetReferredTypeId()).GetDescription(names).Add( + Side::LEFT, Precedence::ATOMIC, GetName()); +} + +Name DataSection::MakeDescription(NameCache &names) const { + // NOTE: not yet encountered in the wild + return Name{"Unimplemented"}; +} + +Name ElfSymbol::MakeDescription(NameCache &names) const { + return Name{symbol_->get_name()}; +} + +Result Void::Equals(const Type &other, State &state) const { + return {}; +} + +Result Ptr::Equals(const Type &other, State &state) const { + Result result; + const auto &o = other.as<Ptr>(); + + const auto ref_diff = Compare(GetTypeAtIndex(GetPointeeTypeId()), + o.GetTypeAtIndex(o.GetPointeeTypeId()), state); + result.MaybeAddDiff("pointed-to type", ref_diff); + return result; +} + +Result Typedef::Equals(const Type &other, State &state) const { + m_assert(false, "should not be called"); // NOLINT + return {}; +} + +Result Qualifier::Equals(const Type &other, State &state) const { + m_assert(false, "should not be called"); // NOLINT + return {}; +} + +Result Integer::Equals(const Type &other, State &state) const { + Result result; + const auto &o = other.as<Integer>(); + + if (isBool() != o.isBool()) { + result.AddDiff(isBool() ? "the first one is a boolean" + : "the second one is a boolean"); + } + if (isSigned() != o.isSigned()) { + result.AddDiff(isSigned() ? "the first one is signed" + : "the second one is signed"); + } + if (isChar() != o.isChar()) { + result.AddDiff(isChar() ? "the first one is a char" + : "the second one is a char"); + } + result.MaybeAddDiff("offset", GetOffset(), o.GetOffset()); + result.MaybeAddDiff("bit size", GetBitSize(), o.GetBitSize()); + if (GetBitSize() != GetByteSize() * 8 && + o.GetBitSize() != o.GetByteSize() * 8) + result.MaybeAddDiff("byte size", GetByteSize(), o.GetByteSize()); + return result; +} + +Result Array::Equals(const Type &other, State &state) const { + Result result; + const auto &o = other.as<Array>(); + + result.MaybeAddDiff("number of elements", + GetNumberOfElements(), o.GetNumberOfElements()); + const auto index_type_diff = + Compare(GetTypeAtIndex(GetIndexTypeId()), + o.GetTypeAtIndex(o.GetIndexTypeId()), state); + result.MaybeAddDiff("index type", index_type_diff); + const auto element_type_diff = + Compare(GetTypeAtIndex(GetElementTypeId()), + o.GetTypeAtIndex(o.GetElementTypeId()), state); + result.MaybeAddDiff("element type", element_type_diff); + + return result; +} + +Result StructUnion::Equals(const Type &other, State &state) const { + Result result; + const auto &o = other.as<StructUnion>(); + + if (GetKind() != o.GetKind()) { + result.AddDiff(GetKind() == BTF_KIND_STRUCT + ? "changed from struct to union" + : "changed from union to struct"); + } + + result.MaybeAddDiff("byte size", GetByteSize(), o.GetByteSize()); + + const auto &members1 = GetMembers(); + const auto &members2 = o.GetMembers(); + std::set<std::string> visited_members; + for (const auto &m1 : members1) { + visited_members.insert(m1.first); + auto iter = members2.find(m1.first); + if (iter == members2.end()) { + std::ostringstream os; + os << "member " << std::quoted(m1.first) << " of type"; + auto diff = Removed(GetTypeAtIndex(m1.second.typeId_), state); + result.AddDiff(os.str(), diff); + } else { + result.MaybeAddDiff([&](std::ostream &os) { + os << "member " << std::quoted(m1.first) << " offset"; + }, m1.second.offset_, iter->second.offset_); + result.MaybeAddDiff([&](std::ostream &os) { + os << "member " << std::quoted(m1.first) << " bitfield size"; + }, m1.second.bitfieldSize_, iter->second.bitfieldSize_); + const auto sub_diff = + Compare(GetTypeAtIndex(m1.second.typeId_), + o.GetTypeAtIndex(iter->second.typeId_), state); + result.MaybeAddDiff([&](std::ostream &os) { + os << "member " << std::quoted(m1.first) << " type"; + }, sub_diff); + } + } + for (const auto &m2 : members2) { + if (visited_members.find(m2.first) == visited_members.end()) { + std::ostringstream os; + os << "member " << std::quoted(m2.first) << " of type"; + auto diff = Added(o.GetTypeAtIndex(m2.second.typeId_), state); + result.AddDiff(os.str(), diff); + } + } + + return result; +} + +Result Enumeration::Equals(const Type &other, State &state) const { + Result result; + const auto &o = other.as<Enumeration>(); + + result.MaybeAddDiff("byte size", GetByteSize(), o.GetByteSize()); + + const auto &enums1 = GetEnums(); + const auto &enums2 = o.GetEnums(); + std::set<std::string> visited_enums; + for (const auto &e1 : enums1) { + visited_enums.insert(e1.first); + auto iter = enums2.find(e1.first); + if (iter == enums2.end()) { + std::ostringstream os; + os << "enumerator " << std::quoted(e1.first) + << " (" << e1.second << ") was removed"; + result.AddDiff(os.str()); + } else { + result.MaybeAddDiff([&](std::ostream &os) { + os << "enumerator " << std::quoted(e1.first) << " value"; + }, e1.second, iter->second); + } + } + for (const auto &e2 : enums2) { + if (visited_enums.find(e2.first) == visited_enums.end()) { + std::ostringstream os; + os << "enumerator " << std::quoted(e2.first) + << " (" << e2.second << ") was added"; + result.AddDiff(os.str()); + } + } + + return result; +} + +Result ForwardDeclaration::Equals(const Type &other, State &state) const { + Result result; + const auto &o = other.as<ForwardDeclaration>(); + + result.MaybeAddDiff("kind", GetFwdKind(), o.GetFwdKind()); + + return result; +} + +Result Function::Equals(const Type &other, State &state) const { + Result result; + const auto &o = other.as<Function>(); + + result.MaybeAddDiff("linkage", GetLinkage(), o.GetLinkage()); + const auto func_proto_diff = + Compare(GetTypeAtIndex(GetReferredTypeId()), + o.GetTypeAtIndex(o.GetReferredTypeId()), state); + result.MaybeAddDiff("type", func_proto_diff); + + return result; +} + +Result FunctionPrototype::Equals(const Type &other, State &state) const { + Result result; + const auto &o = other.as<FunctionPrototype>(); + + const auto return_type_diff = + Compare(GetTypeAtIndex(GetReturnTypeId()), + o.GetTypeAtIndex(o.GetReturnTypeId()), state); + result.MaybeAddDiff("return type", return_type_diff); + + const auto ¶meters1 = GetParameters(); + const auto ¶meters2 = o.GetParameters(); + size_t min = std::min(parameters1.size(), parameters2.size()); + for (size_t i = 0; i < min; ++i) { + const auto &p1 = parameters1.at(i); + const auto &p2 = parameters2.at(i); + const auto sub_diff = Compare(GetTypeAtIndex(p1.typeId_), + o.GetTypeAtIndex(p2.typeId_), state); + result.MaybeAddDiff([&](std::ostream &os) { + os << "parameter " << i + 1; + const auto &n1 = p1.name_; + const auto &n2 = p2.name_; + if (n1 == n2 && !n1.empty()) { + os << " (" << std::quoted(n1) << ")"; + } else if (n1 != n2) { + os << " ("; + if (!n1.empty()) os << "was " << std::quoted(n1); + if (!n1.empty() && !n2.empty()) os << ", "; + if (!n2.empty()) os << "now " << std::quoted(n2); + os << ")"; + } + os << " type"; + }, sub_diff); + } + + bool added = parameters1.size() < parameters2.size(); + const auto ¶meters = added ? parameters2 : parameters1; + for (size_t i = min; i < parameters.size(); ++i) { + const auto ¶meter = parameters.at(i); + std::ostringstream os; + os << "parameter " << i + 1; + if (!parameter.name_.empty()) + os << " (" << std::quoted(parameter.name_) << ")"; + os << " of type"; + const auto ¶meter_type = GetTypeAtIndex(parameter.typeId_); + auto diff = added ? Added(parameter_type, state) + : Removed(parameter_type, state); + result.AddDiff(os.str(), diff); + } + + return result; +} + +// NOTE: not yet encountered in the wild +Result Variable::Equals(const Type &other, State &state) const { + Result result; + const auto &o = other.as<Variable>(); + + result.MaybeAddDiff("linkage", GetLinkage(), o.GetLinkage()); + const auto var_diff = Compare(GetTypeAtIndex(GetVarTypeId()), + o.GetTypeAtIndex(o.GetVarTypeId()), state); + result.MaybeAddDiff("type", var_diff); + + return result; +} + +Result DataSection::Equals(const Type &other, State &state) const { + Result result; + result.AddDiff("Unimplemented"); + + // NOTE: not yet encountered in the wild + m_assert(false, "Unimplemented\n"); // NOLINT + + return result; +} + +Result ElfSymbol::Equals(const Type &other, State &state) const { + Result result; + const auto &o = other.as<ElfSymbol>(); + // TODO: compare ELF symbol attributes + const auto type_diff = Compare(GetTypeAtIndex(type_id_), + o.GetTypeAtIndex(o.type_id_), state); + result.MaybeAddDiff("type", type_diff); + return result; +} + +const Type &Type::ResolveQualifiers(std::set<Kind> &qualifiers) const { + if (kind_ == BTF_KIND_ARRAY || kind_ == BTF_KIND_FUNC_PROTO) { + // There should be no qualifiers here. + qualifiers.clear(); + } + return *this; +} + +const Type &Qualifier::ResolveQualifiers( + std::set<Kind> &qualifiers) const { + qualifiers.insert(GetKind()); + return GetTypeAtIndex(GetQualifiedTypeId()).ResolveQualifiers(qualifiers); +} + +const Type &Type::ResolveTypedef( + std::vector<std::string_view> &typedefs) const { + return *this; +} + +const Type &Typedef::ResolveTypedef( + std::vector<std::string_view> &typedefs) const { + typedefs.push_back(GetName()); + return GetTypeAtIndex(GetReferredTypeId()).ResolveTypedef(typedefs); +} + +std::ostream &operator<<(std::ostream &os, const Type &bt) { + auto name = bt.GetName(); + os << kRawKindNames[bt.GetKind()] + << " '" << (name.empty() ? "(anon)" : name) << '\''; + return os; +} + +std::ostream &operator<<(std::ostream &os, const Ptr &bp) { + os << static_cast<const Type &>(bp) + << " type_id=" << bp.GetPointeeTypeId() + << '\n'; + return os; +} + +std::ostream &operator<<(std::ostream &os, const Typedef &bp) { + os << static_cast<const Type &>(bp) + << " type_id=" << bp.GetReferredTypeId() + << '\n'; + return os; +} + +std::ostream &operator<<(std::ostream &os, const Qualifier &bp) { + os << static_cast<const Type &>(bp) + << " type_id=" << bp.GetQualifiedTypeId() + << '\n'; + return os; +} + +std::ostream &operator<<(std::ostream &os, const Integer &bi) { + os << static_cast<const Type &>(bi) + << " size=" << bi.GetByteSize() + << " bits_offset=" << bi.GetOffset() + << " nr_bits=" << bi.GetBitSize() + << " bool=" << bi.isBool() + << " char=" << bi.isChar() + << " signed=" << bi.isSigned() + << '\n'; + return os; +} + +std::ostream &operator<<(std::ostream &os, const Array &ba) { + os << static_cast<const Type &>(ba) + << " type_id=" << ba.GetElementTypeId() + << " index_type_id=" << ba.GetIndexTypeId() + << " nr_elems=" << ba.GetNumberOfElements() + << '\n'; + return os; + } + +std::ostream &operator<<(std::ostream &os, const StructUnion &bsu) { + os << static_cast<const Type &>(bsu) + << " size=" << bsu.GetByteSize() + << " vlen=" << bsu.GetMembers().size() << '\n'; + for (const auto &member : bsu.GetMembers()) { + os << "\t'" << member.first << '\'' + << " type_id=" << member.second.typeId_ + << " bits_offset=" << member.second.offset_; + if (member.second.bitfieldSize_) + os << " bitfield_size=" << member.second.bitfieldSize_; + os << '\n'; + } + return os; +} + +std::ostream &operator<<(std::ostream &os, const Enumeration &be) { + os << static_cast<const Type &>(be) + << " size=" << be.GetByteSize() + << " vlen=" << be.GetEnums().size() + << '\n'; + for (const auto &e : be.GetEnums()) { + os << "\t'" << e.first << "' val=" << e.second << '\n'; + } + return os; +} + +std::ostream &operator<<(std::ostream &os, const ForwardDeclaration &bfd) { + os << static_cast<const Type &>(bfd) + << " fwd_kind=" << bfd.GetFwdKind() + << '\n'; + return os; +} + +std::ostream &operator<<(std::ostream &os, const Function &bf) { + os << static_cast<const Type &>(bf) + << " type_id=" << bf.GetReferredTypeId() + << " linkage=" << bf.GetLinkage() + << '\n'; + return os; +} + +std::ostream &operator<<(std::ostream &os, const FunctionPrototype &bfp) { + os << static_cast<const Type &>(bfp) + << " ret_type_id=" << bfp.GetReturnTypeId() + << " vlen=" << bfp.GetParameters().size() + << '\n'; + for (const auto ¶m : bfp.GetParameters()) { + os << "\t'" << (param.name_.empty() ? "(anon)" : param.name_) + << "' type_id=" << param.typeId_ << '\n'; + } + return os; +} + +std::ostream &operator<<(std::ostream &os, const Variable &bv) { + // NOTE: The odd comma is to match bpftool dump. + os << static_cast<const Type &>(bv) + << " type_id=" << bv.GetVarTypeId() + << ", linkage=" << bv.GetLinkage() + << '\n'; + return os; +} + +std::ostream &operator<<(std::ostream &os, const DataSection &bds) { + os << static_cast<const Type &>(bds) + << " size=" << bds.GetByteSize() + << '\n'; + for (const auto &secinfo : bds.GetSecinfos()) { + os << "\ttype_id=" << secinfo.typeId_ + << " offset=" << secinfo.offset_ + << " size=" << secinfo.bytesize_ << '\n'; + } + return os; +} + +std::ostream &operator<<(std::ostream &os, const ElfSymbol &bes) { + os << static_cast<const Type &>(bes); + // TODO: report ELF symbol attributes + os << " type=" << bes.GetTypeId() + << '\n'; + return os; +} + +std::ostream &operator<<(std::ostream &os, ForwardDeclarationKind kind) { + switch (kind) { + case ForwardDeclarationKind::STRUCT: + os << "struct"; + break; + case ForwardDeclarationKind::UNION: + os << "union"; + break; + } + return os; +} + +std::ostream &operator<<(std::ostream &os, Variable::Linkage linkage) { + auto ix = static_cast<size_t>(linkage); + return os << (ix < kVarLinkage.size() ? kVarLinkage[ix] : "(unknown)"); +} + +std::ostream &operator<<(std::ostream &os, Function::Linkage linkage) { + auto ix = static_cast<size_t>(linkage); + return os << (ix < kFunLinkage.size() ? kFunLinkage[ix] : "(unknown)"); +} + +Structs::Structs(const char *start, + std::unique_ptr<abigail::ir::environment> env, + const abigail::symtab_reader::symtab_sptr tab, + const bool verbose) + : env_(std::move(env)), + tab_(tab), + verbose_(verbose) { + header_ = reinterpret_cast<const btf_header *>(start); + m_assert(header_->magic == 0xEB9F, "Magic field must be 0xEB9F for BTF"); + + type_section_ = reinterpret_cast<const btf_type *>(start + header_->hdr_len + + header_->type_off); + str_section_ = start + header_->hdr_len + header_->str_off; + + // every btf_type struct in the type section has an implicit type id. + // type id 0 is reserved for void type, so it is set to a Void here. + // The type section is parsed sequentially and type id is assigned to each + // recognized type starting from id 1. + types_.push_back(std::make_unique<Void>(types_, 0, "void", 0)); + + if (verbose_) { + PrintHeader(); + } + BuildTypes(); + if (verbose_) { + PrintStringSection(); + } + + // NOTE: a whole bunch of Linux kernel symbols appear with duplicate (but not + // necessarily identical) BTF type information + // + // TODO: find a better way of resolving this + bad_prefix_1_ = "__arm64_sys_"; + bad_prefix_2_ = "__arm64_compat_sys_"; + bad_names_ = { + "arch_prctl_spec_ctrl_get", + "arch_prctl_spec_ctrl_set", + "ioremap_cache", + "kvm_arch_set_irq_inatomic", + "module_frob_arch_sections", + "vsnprintf" + }; +} + +void Structs::PrintHeader() { + std::cout << "BTF header:\n" + << "\tmagic " << header_->magic + << ", version " << static_cast<int>(header_->version) + << ", flags " << static_cast<int>(header_->flags) + << ", hdr_len " << header_->hdr_len << "\n" + << "\ttype_off " << header_->type_off + << ", type_len " << header_->type_len << "\n" + << "\tstr_off " << header_->str_off + << ", str_len " << header_->str_len << "\n"; +} + +// vlen: vector length, the number of struct/union members +std::map<std::string, Member> Structs::BuildMembers( + bool kflag, const btf_member *members, size_t vlen) { + std::map<std::string, Member> result; + int anonymous = 0; + for (size_t i = 0; i < vlen; ++i) { + const auto raw_offset = members[i].offset; + Member member{ + .typeId_ = members[i].type, + .offset_ = kflag ? BTF_MEMBER_BIT_OFFSET(raw_offset) : raw_offset, + .bitfieldSize_ = kflag ? BTF_MEMBER_BITFIELD_SIZE(raw_offset) : 0}; + std::string name = std::string(GetName(members[i].name_off)); + if (name.empty()) { + name = "anon member #" + std::to_string(anonymous); + ++anonymous; + } + result.emplace(name, member); + } + return result; +} + +// vlen: vector length, the number of enum values +std::map<std::string, int> Structs::BuildEnums(const struct btf_enum *enums, + size_t vlen) { + std::map<std::string, int> result; + for (size_t i = 0; i < vlen; ++i) { + result.emplace(std::string(GetName(enums[i].name_off)), enums[i].val); + } + return result; +} + +// vlen: vector length, the number of parameters +std::vector<Parameter> Structs::BuildParams(const struct btf_param *params, + size_t vlen) { + std::vector<Parameter> result; + result.reserve(vlen); + for (size_t i = 0; i < vlen; ++i) { + Parameter parameter{ + .name_ = std::string(GetName(params[i].name_off)), + .typeId_ = params[i].type}; + result.push_back(parameter); + } + return result; +} + +// vlen: vector length, the number of variables +std::vector<Secinfo> Structs::BuildDatasec(const btf_type *type, + size_t vlen) { + std::vector<Secinfo> result; + result.reserve(vlen); + const auto *secinfos = reinterpret_cast<const btf_var_secinfo *>(type + 1); + for (size_t i = 0; i < vlen; ++i) { + Secinfo secinfo{.typeId_ = secinfos[i].type, + .offset_ = secinfos[i].offset, + .bytesize_ = secinfos[i].size}; + result.push_back(secinfo); + } + return result; +} + +void Structs::BuildTypes() { + m_assert(!(header_->type_off & (sizeof(uint32_t) - 1)), "Unaligned type_off"); + if (header_->type_len == 0) { + std::cerr << "No types found"; + return; + } + if (verbose_) { + std::cout << "Type section:\n"; + } + + const char *curr = reinterpret_cast<const char *>(type_section_); + const char *end = curr + header_->type_len; + uint32_t index = 1; + while (curr < end) { + const btf_type *t = reinterpret_cast<const btf_type *>(curr); + int type_size = BuildOneType(t, index); + m_assert(type_size > 0, "Could not identify BTF type"); + curr += type_size; + ++index; + } + + BuildElfSymbols(); +} + +int Structs::BuildOneType(const btf_type *t, uint32_t index) { + const auto kind = BTF_INFO_KIND(t->info); + const auto vlen = BTF_INFO_VLEN(t->info); + // Data following the btf_type struct. + const void *data = reinterpret_cast<const void *>(t + 1); + m_assert(kind >= 0 && kind < NR_BTF_KINDS, "Unknown BTF kind"); + + if (verbose_) std::cout << '[' << index << "] "; + int type_size = sizeof(struct btf_type); + switch (kind) { + case BTF_KIND_INT: { + const auto bits = *reinterpret_cast<const uint32_t *>(data); + types_.push_back(std::make_unique<Integer>( + types_, index, GetName(t->name_off), kind, + BTF_INT_ENCODING(bits), BTF_INT_OFFSET(bits), BTF_INT_BITS(bits), + t->size)); + if (verbose_) { + std::cout << types_.back()->as<Integer>(); + } + type_size += sizeof(uint32_t); + break; + } + case BTF_KIND_PTR: { + types_.push_back(std::make_unique<Ptr>( + types_, index, GetName(t->name_off), kind, t->type)); + if (verbose_) { + std::cout << types_.back()->as<Ptr>(); + } + break; + } + case BTF_KIND_TYPEDEF: { + types_.push_back(std::make_unique<Typedef>( + types_, index, GetName(t->name_off), kind, t->type)); + if (verbose_) { + std::cout << types_.back()->as<Typedef>(); + } + break; + } + case BTF_KIND_VOLATILE: + case BTF_KIND_CONST: + case BTF_KIND_RESTRICT: { + types_.push_back(std::make_unique<Qualifier>( + types_, index, GetName(t->name_off), kind, t->type)); + if (verbose_) { + std::cout << types_.back()->as<Qualifier>(); + } + break; + } + case BTF_KIND_ARRAY: { + const auto *array = reinterpret_cast<const struct btf_array *>(data); + types_.push_back(std::make_unique<Array>( + types_, index, GetName(t->name_off), kind, array->type, + array->index_type, array->nelems)); + if (verbose_) { + std::cout << types_.back()->as<Array>(); + } + type_size += sizeof(struct btf_array); + break; + } + case BTF_KIND_STRUCT: + case BTF_KIND_UNION: { + const bool kflag = BTF_INFO_KFLAG(t->info); + const auto *btf_members = reinterpret_cast<const btf_member *>(data); + const auto members = BuildMembers(kflag, btf_members, vlen); + types_.push_back(std::make_unique<StructUnion>( + types_, index, GetName(t->name_off), kind, t->size, members)); + if (verbose_) { + std::cout << types_.back()->as<StructUnion>(); + } + type_size += vlen * sizeof(struct btf_member); + break; + } + case BTF_KIND_ENUM: { + const auto *enums = reinterpret_cast<const struct btf_enum *>(data); + std::map<std::string, int> enumerators = BuildEnums(enums, vlen); + types_.push_back(std::make_unique<Enumeration>( + types_, index, GetName(t->name_off), kind, + t->size, enumerators)); + if (verbose_) { + std::cout << types_.back()->as<Enumeration>(); + } + type_size += vlen * sizeof(struct btf_enum); + break; + } + case BTF_KIND_FWD: { + const bool kflag = BTF_INFO_KFLAG(t->info); + types_.push_back(std::make_unique<ForwardDeclaration>( + types_, index, GetName(t->name_off), kind, kflag)); + if (verbose_) { + std::cout << types_.back()->as<ForwardDeclaration>(); + } + break; + } + case BTF_KIND_FUNC: { + const auto name = GetName(t->name_off); + types_.push_back(std::make_unique<Function>( + types_, index, name, kind, t->type, + Function::Linkage(vlen))); + if (verbose_) { + std::cout << types_.back()->as<Function>(); + } + bool inserted = btf_symbol_types_.insert({name, t->type}).second; + if (!inserted) { + // NOTE: duplicate BTF symbols could be considered a bug in pahole + // + // TODO: remove these checks once resolved + bool known = !name.compare(0, bad_prefix_1_.size(), bad_prefix_1_) || + !name.compare(0, bad_prefix_2_.size(), bad_prefix_2_) || + std::find(bad_names_.begin(), bad_names_.end(), name) != + bad_names_.end(); + m_assert(known, "Insertion failed, duplicate found in symbol map"); + (void)known; + } + btf_symbols_.insert({name, types_.back().get()}); + break; + } + case BTF_KIND_FUNC_PROTO: { + const auto *params = reinterpret_cast<const btf_param *>(data); + std::vector<Parameter> parameters = BuildParams(params, vlen); + types_.push_back(std::make_unique<FunctionPrototype>( + types_, index, GetName(t->name_off), kind, t->type, + parameters)); + if (verbose_) { + std::cout << types_.back()->as<FunctionPrototype>(); + } + type_size += vlen * sizeof(struct btf_param); + break; + } + case BTF_KIND_VAR: { + // NOTE: not yet encountered in the wild + const auto *variable = reinterpret_cast<const struct btf_var *>(data); + const auto name = GetName(t->name_off); + types_.push_back(std::make_unique<Variable>( + types_, index, name, kind, t->type, + Variable::Linkage(variable->linkage))); + if (verbose_) { + std::cout << types_.back()->as<Variable>(); + } + + bool inserted = btf_symbol_types_.insert({name, t->type}).second; + m_assert(inserted, "Insertion failed, duplicate found in symbol map"); + (void)inserted; + btf_symbols_.insert({name, types_.back().get()}); + + type_size += sizeof(struct btf_var); + break; + } + case BTF_KIND_DATASEC: { + std::vector<Secinfo> secinfos = BuildDatasec(t, vlen); + types_.push_back(std::make_unique<DataSection>( + types_, index, GetName(t->name_off), kind, t->size, + secinfos)); + if (verbose_) { + std::cout << types_.back()->as<DataSection>(); + } + type_size += vlen * sizeof(struct btf_var_secinfo); + } + } + return type_size; +} + +std::string_view Structs::GetName(uint32_t name_off) { + m_assert(name_off < header_->str_len, + "The name offset exceeds the section length"); + const char *section_end = str_section_ + header_->str_len; + const char *name_end = std::find(&str_section_[name_off], section_end, '\0'); + m_assert(name_end < section_end, + "The name continues past the string section limit"); + (void)name_end; + + std::string_view name{&str_section_[name_off]}; + return name; +} + +void Structs::PrintStringSection() { + std::cout << "String section:\n"; + const char *curr = str_section_; + const char *limit = str_section_ + header_->str_len; + while (curr < limit) { + const char *pos = std::find(curr, limit, '\0'); + m_assert(pos < limit, "Error reading the string section"); + std::cout << ' ' << curr; + curr = pos + 1; + } + std::cout << '\n'; +} + +void Structs::BuildElfSymbols() { + const auto filter = [&]() { + auto filter = tab_->make_filter(); + filter.set_public_symbols(); + return filter; + }(); + for (const auto &symbol : + abigail::symtab_reader::filtered_symtab(*tab_, filter)) { + const auto &symbol_name = symbol->get_name(); + const auto &main_symbol_name = symbol->get_main_symbol()->get_name(); + auto it = btf_symbol_types_.find(main_symbol_name); + if (it == btf_symbol_types_.end()) { + // missing BTF information is tracked explicitly + std::cerr << "ELF symbol " << std::quoted(symbol_name); + if (symbol_name != main_symbol_name) + std::cerr << " (aliased to " << std::quoted(main_symbol_name) << ')'; + std::cerr << " BTF info missing\n"; + types_.push_back(nullptr); + } else { + uint32_t type_id = it->second; + types_.push_back(std::make_unique<ElfSymbol>(types_, symbol, type_id)); + } + elf_symbols_.emplace(symbol_name, types_.back().get()); + } +} + +class ElfHandle { + public: + ElfHandle(const std::string &path) : dwfl_(nullptr, dwfl_end) { + string name; + tools_utils::base_name(path, name); + elf_version(EV_CURRENT); + + dwfl_ = std::unique_ptr<Dwfl, decltype(&dwfl_end)>( + dwfl_begin(&offline_callbacks_), dwfl_end); + auto dwfl_module = dwfl_report_offline(dwfl_.get(), name.c_str(), + path.c_str(), -1); + GElf_Addr bias; + elf_handle_ = dwfl_module_getelf(dwfl_module, &bias); + } + + // Conversion operator to act as a drop-in replacement for Elf* + operator Elf *() const { return elf_handle_; } + + Elf *get() const { return elf_handle_; } + + private: + // Dwfl owns all our data, hence only keep track of this + std::unique_ptr<Dwfl, decltype(&dwfl_end)> dwfl_; + Elf *elf_handle_; + + Dwfl_Callbacks offline_callbacks_; +}; + +Structs ReadFile(const std::string &path, bool verbose) { + using abigail::symtab_reader::symtab; + + ElfHandle elf(path); + m_assert(elf.get() != nullptr, "Could not get elf handle from file."); + + Elf_Scn *btf_section = + abigail::elf_helpers::find_section(elf, ".BTF", SHT_PROGBITS); + m_assert(btf_section != nullptr, + "The given file does not have a BTF section"); + Elf_Data *elf_data = elf_rawdata(btf_section, 0); + m_assert(elf_data != nullptr, "The BTF section is invalid"); + const char *btf_start = static_cast<char *>(elf_data->d_buf); + + auto env = std::make_unique<abigail::ir::environment>(); + auto tab = symtab::load(elf, env.get()); + + return Structs(btf_start, std::move(env), std::move(tab), verbose); +} + +} // end namespace btf +} // end namespace abigail -- 2.32.0.272.g935e593368-goog ^ permalink raw reply [flat|nested] 14+ messages in thread
* [PATCH 5/6] BTF: add btfinfo and btfdiff tools 2021-06-11 15:33 [PATCH 0/6] BTF ABI Giuliano Procida ` (3 preceding siblings ...) 2021-06-11 15:33 ` [PATCH 4/6] BTF: add core functionality Giuliano Procida @ 2021-06-11 15:33 ` Giuliano Procida 2021-06-11 15:33 ` [PATCH 6/6] BTF: clang-format all the new source files Giuliano Procida 2021-06-22 10:33 ` [PATCH v2 0/6] BTF ABI Giuliano Procida 6 siblings, 0 replies; 14+ messages in thread From: Giuliano Procida @ 2021-06-11 15:33 UTC (permalink / raw) To: libabigail Cc: dodji, kernel-team, gprocida, maennich, teguiani, Maria Teguiani This commit adds BTF command line tools. They are fairly thin wrappers around the core BTF functionality. The files are almost a straight copy of the originals. Changes: - Files renamed and #includes updated. * tools/Makefile.am: Compile BTF tools, conditional on C++17 and <linux/btf.h>. * tools/btfdiff.cc: New utility that compares BTF information. * tools/btfinfo.cc: New utility that dumps BTF information. Co-authored-by: Maria Teguiani <teguiani@google.com> Signed-off-by: Giuliano Procida <gprocida@google.com> --- tools/Makefile.am | 14 ++++++++++ tools/btfdiff.cc | 67 +++++++++++++++++++++++++++++++++++++++++++++++ tools/btfinfo.cc | 19 ++++++++++++++ 3 files changed, 100 insertions(+) create mode 100644 tools/btfdiff.cc create mode 100644 tools/btfinfo.cc diff --git a/tools/Makefile.am b/tools/Makefile.am index 648a71b5..bd310c18 100644 --- a/tools/Makefile.am +++ b/tools/Makefile.am @@ -9,6 +9,12 @@ else noinst_SCRIPTS = fedabipkgdiff endif +if ENABLE_CXX17 +if HAVE_BTF + bin_PROGRAMS += btfinfo btfdiff +endif +endif + noinst_PROGRAMS = abisym abinilint abidiff_SOURCES = abidiff.cc @@ -45,6 +51,14 @@ kmidiffdir = $(bindir) kmidiff_LDADD = $(abs_top_builddir)/src/libabigail.la kmidiff_LDFLAGS = -pthread +btfinfo_SOURCES = btfinfo.cc +btfinfodir = $(bindir) +btfinfo_LDADD = ../src/libabigail.la + +btfdiff_SOURCES = btfdiff.cc +btfdiffdir = $(bindir) +btfdiff_LDADD = ../src/libabigail.la + AM_CXXFLAGS = \ $(VISIBILITY_FLAGS) -I$(abs_top_srcdir)/include \ -I$(abs_top_srcdir)/tools -fPIC diff --git a/tools/btfdiff.cc b/tools/btfdiff.cc new file mode 100644 index 00000000..58c40e42 --- /dev/null +++ b/tools/btfdiff.cc @@ -0,0 +1,67 @@ +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// -*- mode: C++ -*- +// +// Copyright (C) 2020-2021 Google, Inc. +// +// Author: Maria Teguiani +// Author: Giuliano Procida + +#include <getopt.h> +#include <string.h> + +#include <iomanip> +#include <iostream> + +#include "abg-btf.h" + +const int kAbiChange = 4; + +int main(int argc, char* argv[]) { + bool use_elf_symbols = true; + static option opts[]{ + {"symbols", required_argument, nullptr, 's'}, + {nullptr, 0, nullptr, 0}, + }; + auto usage = [&]() { + std::cerr << "usage: " << argv[0] << " [-s|--symbols type] file1 file2\n" + << " where type is elf (the default) or btf\n"; + return 1; + }; + auto bad_arg = [&](int ix) { + std::cerr << argv[0] << ": option '--" << opts[ix].name + << "' unrecognized argument '" << optarg << "'\n"; + return usage(); + }; + while (true) { + int ix; + int c = getopt_long(argc, argv, "s:", opts, &ix); + if (c == -1) + break; + switch (c) { + case 's': + if (!strcmp(optarg, "btf")) + use_elf_symbols = false; + else if (!strcmp(optarg, "elf")) + use_elf_symbols = true; + else + return bad_arg(ix); + break; + default: + return usage(); + } + } + if (optind + 2 != argc) + return usage(); + + const auto structs1 = abigail::btf::ReadFile(argv[optind++]); + const auto structs2 = abigail::btf::ReadFile(argv[optind++]); + const auto& map1 = structs1.GetSymbols(use_elf_symbols); + const auto& map2 = structs2.GetSymbols(use_elf_symbols); + abigail::btf::Outcomes outcomes; + auto result = abigail::btf::Type::CompareSymbols(map1, map2, outcomes); + abigail::btf::NameCache names; + abigail::btf::Seen seen; + abigail::btf::Print(result.details_, outcomes, seen, names, std::cout); + + return result.equals_ ? 0 : kAbiChange; +} diff --git a/tools/btfinfo.cc b/tools/btfinfo.cc new file mode 100644 index 00000000..dbda7945 --- /dev/null +++ b/tools/btfinfo.cc @@ -0,0 +1,19 @@ +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// -*- mode: C++ -*- +// +// Copyright (C) 2020 Google, Inc. +// +// Author: Maria Teguiani + +#include "abg-btf.h" + +int main(int argc, const char *argv[]) { + if (argc != 2) { + std::cerr << "Please specify the path to a BTF file."; + return 1; + } + + (void) abigail::btf::ReadFile(argv[1], /* verbose = */ true); + + return 0; +} -- 2.32.0.272.g935e593368-goog ^ permalink raw reply [flat|nested] 14+ messages in thread
* [PATCH 6/6] BTF: clang-format all the new source files 2021-06-11 15:33 [PATCH 0/6] BTF ABI Giuliano Procida ` (4 preceding siblings ...) 2021-06-11 15:33 ` [PATCH 5/6] BTF: add btfinfo and btfdiff tools Giuliano Procida @ 2021-06-11 15:33 ` Giuliano Procida 2021-06-22 10:33 ` [PATCH v2 0/6] BTF ABI Giuliano Procida 6 siblings, 0 replies; 14+ messages in thread From: Giuliano Procida @ 2021-06-11 15:33 UTC (permalink / raw) To: libabigail; +Cc: dodji, kernel-team, gprocida, maennich, teguiani This is to bring them closer to the libabigail coding style. * include/abg-btf.h: Reformatted with clang-format. * include/abg-scc.h: Reformatted with clang-format. * src/abg-btf.cc: Reformatted with clang-format. * tests/test-scc.cc: Reformatted with clang-format. * tools/btfdiff.cc: Reformatted with clang-format. * tools/btfinfo.cc: Reformatted with clang-format. Signed-off-by: Giuliano Procida <gprocida@google.com> --- include/abg-btf.h | 1025 ++++++++++++++++-------- include/abg-scc.h | 67 +- src/abg-btf.cc | 1903 ++++++++++++++++++++++++++------------------- tests/test-scc.cc | 203 +++-- tools/btfdiff.cc | 40 +- tools/btfinfo.cc | 13 +- 6 files changed, 1964 insertions(+), 1287 deletions(-) diff --git a/include/abg-btf.h b/include/abg-btf.h index d47b4ac9..478a2a78 100644 --- a/include/abg-btf.h +++ b/include/abg-btf.h @@ -26,16 +26,19 @@ #include "abg-ir.h" #include "abg-scc.h" -namespace abigail { -namespace btf { +namespace abigail +{ +namespace btf +{ -#define m_assert(expr, msg) assert(((void)(msg), (expr))) +#define m_assert(expr, msg) assert(((void) (msg), (expr))) using Kind = uint32_t; // A Member refers to a data element of a struct or union, used in the context // of StructUnion -struct Member { +struct Member +{ uint32_t typeId_; uint32_t offset_; uint32_t bitfieldSize_; @@ -43,110 +46,156 @@ struct Member { // A Parameter refers to a variable declared in the function declaration, used // in the context of Function -struct Parameter { +struct Parameter +{ std::string name_; uint32_t typeId_; }; -struct Secinfo { +struct Secinfo +{ uint32_t typeId_; uint32_t offset_; uint32_t bytesize_; }; -enum class ForwardDeclarationKind { STRUCT, UNION }; +enum class ForwardDeclarationKind +{ + STRUCT, + UNION +}; -std::ostream &operator<<(std::ostream &os, ForwardDeclarationKind kind); +std::ostream& +operator<<(std::ostream& os, ForwardDeclarationKind kind); class Type; -using Comparison = std::pair<const Type *, const Type *>; +using Comparison = std::pair<const Type*, const Type*>; -enum class Precedence { NIL, POINTER, ARRAY_FUNCTION, ATOMIC }; -enum class Side { LEFT, RIGHT }; +enum class Precedence +{ + NIL, + POINTER, + ARRAY_FUNCTION, + ATOMIC +}; +enum class Side +{ + LEFT, + RIGHT +}; -class Name { - public: +class Name +{ +public: explicit Name(std::string_view name) - : left_(name), precedence_(Precedence::NIL), right_() {} + : left_(name), precedence_(Precedence::NIL), right_() + { + } Name(std::string_view left, Precedence precedence, std::string_view right) - : left_(left), precedence_(precedence), right_(right) {} - Name Add(Side side, Precedence precedence, std::string_view text) const; - Name Qualify(const std::set<Kind> &qualifiers) const; - std::ostream &Print(std::ostream &os) const; - - private: + : left_(left), precedence_(precedence), right_(right) + { + } + Name + Add(Side side, Precedence precedence, std::string_view text) const; + Name + Qualify(const std::set<Kind>& qualifiers) const; + std::ostream& + Print(std::ostream& os) const; + +private: std::string left_; Precedence precedence_; std::string right_; }; -std::ostream &operator<<(std::ostream &os, const Name &name); +std::ostream& +operator<<(std::ostream& os, const Name& name); -using NameCache = std::unordered_map<const Type *, Name>; +using NameCache = std::unordered_map<const Type*, Name>; -struct DiffDetail { - DiffDetail(const std::string &text, const std::optional<Comparison> &edge) - : text_(text), edge_(edge) {} +struct DiffDetail +{ + DiffDetail(const std::string& text, const std::optional<Comparison>& edge) + : text_(text), edge_(edge) + { + } std::string text_; std::optional<Comparison> edge_; }; using Diff = std::vector<DiffDetail>; -struct Result { - void AddDiff(const std::string &text) { +struct Result +{ + void + AddDiff(const std::string& text) + { equals_ = false; details_.emplace_back(text, std::optional<Comparison>()); } - void AddDiff(const std::string &text, Comparison comparison) { + void + AddDiff(const std::string& text, Comparison comparison) + { equals_ = false; details_.emplace_back(text, comparison); } - void MaybeAddDiff(const std::string &text, - const std::pair<bool, std::optional<Comparison>> &p) { + void + MaybeAddDiff(const std::string& text, + const std::pair<bool, std::optional<Comparison>>& p) + { equals_ &= p.first; - const auto &diff = p.second; + const auto& diff = p.second; if (diff) details_.emplace_back(text, diff); } // Maximally powerful lazy version, takes a function that outputs an "edge" // diff description, to be used only when a diff is present. - void MaybeAddDiff(std::function<void(std::ostream &)> text, - const std::pair<bool, std::optional<Comparison>> &p) { + void + MaybeAddDiff(std::function<void(std::ostream&)> text, + const std::pair<bool, std::optional<Comparison>>& p) + { equals_ &= p.first; - const auto &diff = p.second; - if (diff) { - std::ostringstream os; - text(os); - details_.emplace_back(os.str(), diff); - } + const auto& diff = p.second; + if (diff) + { + std::ostringstream os; + text(os); + details_.emplace_back(os.str(), diff); + } } - template<typename T> void MaybeAddDiff( - const std::string &text, const T &before, const T &after) { - if (before != after) { - equals_ = false; - std::ostringstream os; - os << text << " changed from " << before << " to " << after; - AddDiff(os.str()); - } + template <typename T> + void + MaybeAddDiff(const std::string& text, const T& before, const T& after) + { + if (before != after) + { + equals_ = false; + std::ostringstream os; + os << text << " changed from " << before << " to " << after; + AddDiff(os.str()); + } } // Lazy version. - template<typename T> void MaybeAddDiff( - std::function<void(std::ostream &)> text, - const T &before, const T &after) { - if (before != after) { - equals_ = false; - std::ostringstream os; - text(os); - os << " changed from " << before << " to " << after; - AddDiff(os.str()); - } + template <typename T> + void + MaybeAddDiff(std::function<void(std::ostream&)> text, + const T& before, + const T& after) + { + if (before != after) + { + equals_ = false; + std::ostringstream os; + text(os); + os << " changed from " << before << " to " << after; + AddDiff(os.str()); + } } bool equals_ = true; @@ -157,22 +206,51 @@ using Outcomes = std::map<Comparison, Diff>; // unvisited (absent) -> started (false) -> finished (true) using Seen = std::map<Comparison, bool>; -void Print(const Comparison &comparison, const Outcomes &outcomes, Seen &seen, - NameCache &names, std::ostream &os, size_t indent = 0); - -void Print(const Diff &details, const Outcomes &outcomes, Seen &seen, - NameCache &names, std::ostream &os, size_t indent = 0); - -class Type { - public: - Type(const std::vector<std::unique_ptr<Type>> &types, uint32_t index, - std::string_view name, Kind kind) - : types_(types), index_(index), name_(name), kind_(kind) {} +void +Print(const Comparison& comparison, + const Outcomes& outcomes, + Seen& seen, + NameCache& names, + std::ostream& os, + size_t indent = 0); + +void +Print(const Diff& details, + const Outcomes& outcomes, + Seen& seen, + NameCache& names, + std::ostream& os, + size_t indent = 0); + +class Type +{ +public: + Type(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, + std::string_view name, + Kind kind) + : types_(types), index_(index), name_(name), kind_(kind) + { + } virtual ~Type() = default; - uint32_t GetIndex() const { return index_; } - std::string_view GetName() const { return name_; } - Kind GetKind() const { return kind_; } - const std::vector<std::unique_ptr<Type>> &GetTypes() const { + uint32_t + GetIndex() const + { + return index_; + } + std::string_view + GetName() const + { + return name_; + } + Kind + GetKind() const + { + return kind_; + } + const std::vector<std::unique_ptr<Type>>& + GetTypes() const + { return types_; } @@ -181,10 +259,12 @@ class Type { // not correct, the assert will trigger in debug mode. In release mode, this // will crash dereferencing the nullptr. template <typename Target> - const Target &as() const { - static_assert(std::is_convertible<Target *, Type *>::value, - "Target must publically inherit Type"); - const Target *t = dynamic_cast<const Target *>(this); + const Target& + as() const + { + static_assert(std::is_convertible<Target*, Type*>::value, + "Target must publically inherit Type"); + const Target* t = dynamic_cast<const Target*>(this); m_assert(t, "Invalid downcast"); return *t; } @@ -192,122 +272,206 @@ class Type { // // The caller must always be prepared to receive a different type as // qualifiers are sometimes discarded. - virtual const Type &ResolveQualifiers(std::set<Kind> &qualifiers) const; - virtual const Type &ResolveTypedef( - std::vector<std::string_view> &typedefs) const; - - const Name &GetDescription(NameCache &names) const; - static Result CompareSymbols( - const std::map<std::string_view, const Type *const> &lhs, - const std::map<std::string_view, const Type *const> &rhs, - Outcomes &outcomes); - - protected: - struct State { - explicit State(Outcomes &o) : outcomes(o), scc(o.value_comp()) { } - Outcomes &outcomes; + virtual const Type& + ResolveQualifiers(std::set<Kind>& qualifiers) const; + virtual const Type& + ResolveTypedef(std::vector<std::string_view>& typedefs) const; + + const Name& + GetDescription(NameCache& names) const; + static Result + CompareSymbols(const std::map<std::string_view, const Type* const>& lhs, + const std::map<std::string_view, const Type* const>& rhs, + Outcomes& outcomes); + +protected: + struct State + { + explicit State(Outcomes& o) : outcomes(o), scc(o.value_comp()) {} + Outcomes& outcomes; std::set<Comparison> known_equal; SCC<Outcomes::value_type> scc; }; - const Type &GetTypeAtIndex(size_t index) const; - - virtual Name MakeDescription(NameCache &names) const = 0; - virtual Result Equals(const Type &other, State &state) const = 0; - static Comparison Removed(const Type &lhs, State &state); - static Comparison Added(const Type &rhs, State &state); - static std::pair<bool, std::optional<Comparison>> Compare( - const Type &lhs, const Type &rhs, State &state); - - private: - static std::string GetDiffMessage(NameCache &names, - const Type &lhs, const Type &rhs, - const std::string &message = std::string()); - const std::vector<std::unique_ptr<Type>> &types_; + const Type& + GetTypeAtIndex(size_t index) const; + + virtual Name + MakeDescription(NameCache& names) const = 0; + virtual Result + Equals(const Type& other, State& state) const = 0; + static Comparison + Removed(const Type& lhs, State& state); + static Comparison + Added(const Type& rhs, State& state); + static std::pair<bool, std::optional<Comparison>> + Compare(const Type& lhs, const Type& rhs, State& state); + +private: + static std::string + GetDiffMessage(NameCache& names, + const Type& lhs, + const Type& rhs, + const std::string& message = std::string()); + const std::vector<std::unique_ptr<Type>>& types_; const uint32_t index_; const std::string name_; const Kind kind_; }; -class Void : public Type { - public: - Void(const std::vector<std::unique_ptr<Type>> &types, uint32_t index, - std::string_view name, Kind kind) - : Type(types, index, name, kind) {} - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; +class Void : public Type +{ +public: + Void(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, + std::string_view name, + Kind kind) + : Type(types, index, name, kind) + { + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; }; -class Ptr : public Type { - public: - Ptr(const std::vector<std::unique_ptr<Type>> &types, uint32_t index, - std::string_view name, Kind kind, uint32_t pointeeTypeId) - : Type(types, index, name, kind), - pointeeTypeId_(pointeeTypeId) {} - uint32_t GetPointeeTypeId() const { return pointeeTypeId_; } - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; - - private: +class Ptr : public Type +{ +public: + Ptr(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, + std::string_view name, + Kind kind, + uint32_t pointeeTypeId) + : Type(types, index, name, kind), pointeeTypeId_(pointeeTypeId) + { + } + uint32_t + GetPointeeTypeId() const + { + return pointeeTypeId_; + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; + +private: const uint32_t pointeeTypeId_; }; -class Typedef : public Type { - public: - Typedef(const std::vector<std::unique_ptr<Type>> &types, uint32_t index, - std::string_view name, Kind kind, uint32_t referredTypeId) - : Type(types, index, name, kind), - referredTypeId_(referredTypeId) {} - uint32_t GetReferredTypeId() const { return referredTypeId_; } - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; - const Type &ResolveTypedef( - std::vector<std::string_view> &typedefs) const final; - - private: +class Typedef : public Type +{ +public: + Typedef(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, + std::string_view name, + Kind kind, + uint32_t referredTypeId) + : Type(types, index, name, kind), referredTypeId_(referredTypeId) + { + } + uint32_t + GetReferredTypeId() const + { + return referredTypeId_; + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; + const Type& + ResolveTypedef(std::vector<std::string_view>& typedefs) const final; + +private: const uint32_t referredTypeId_; }; -class Qualifier : public Type { - public: - Qualifier(const std::vector<std::unique_ptr<Type>> &types, - uint32_t index, std::string_view name, Kind kind, - uint32_t qualifiedTypeId) - : Type(types, index, name, kind), - qualifiedTypeId_(qualifiedTypeId) {} - uint32_t GetQualifiedTypeId() const { return qualifiedTypeId_; } - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; - const Type &ResolveQualifiers(std::set<Kind> &qualifiers) const final; - - private: +class Qualifier : public Type +{ +public: + Qualifier(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, + std::string_view name, + Kind kind, + uint32_t qualifiedTypeId) + : Type(types, index, name, kind), qualifiedTypeId_(qualifiedTypeId) + { + } + uint32_t + GetQualifiedTypeId() const + { + return qualifiedTypeId_; + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; + const Type& + ResolveQualifiers(std::set<Kind>& qualifiers) const final; + +private: const uint32_t qualifiedTypeId_; }; -class Integer : public Type { - public: - Integer(const std::vector<std::unique_ptr<Type>> &types, uint32_t index, - std::string_view name, Kind kind, uint32_t encoding, - uint32_t offset, uint32_t bitsize, uint32_t bytesize) - : Type(types, index, name, kind), - offset_(offset), - bitsize_(bitsize), - bytesize_(bytesize), - isBool_(encoding & BTF_INT_BOOL), - isSigned_(encoding & BTF_INT_SIGNED), - isChar_(encoding & BTF_INT_CHAR) {} - bool isBool() const { return isBool_; } - bool isSigned() const { return isSigned_; } - bool isChar() const { return isChar_; } - uint32_t GetOffset() const { return offset_; } +class Integer : public Type +{ +public: + Integer(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, + std::string_view name, + Kind kind, + uint32_t encoding, + uint32_t offset, + uint32_t bitsize, + uint32_t bytesize) + : Type(types, index, name, kind), + offset_(offset), + bitsize_(bitsize), + bytesize_(bytesize), + isBool_(encoding & BTF_INT_BOOL), + isSigned_(encoding & BTF_INT_SIGNED), + isChar_(encoding & BTF_INT_CHAR) + { + } + bool + isBool() const + { + return isBool_; + } + bool + isSigned() const + { + return isSigned_; + } + bool + isChar() const + { + return isChar_; + } + uint32_t + GetOffset() const + { + return offset_; + } // GetBitSize() gives the semantics of the field. GetByteSize() gives the // storage size, and is equal or greater than GetBitSize()*8 - uint32_t GetBitSize() const { return bitsize_; } - uint32_t GetByteSize() const { return bytesize_; } - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; + uint32_t + GetBitSize() const + { + return bitsize_; + } + uint32_t + GetByteSize() const + { + return bytesize_; + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; - private: +private: const uint32_t offset_; const uint32_t bitsize_; const uint32_t bytesize_; @@ -316,236 +480,409 @@ class Integer : public Type { const bool isChar_; }; -class Array : public Type { - public: - Array(const std::vector<std::unique_ptr<Type>> &types, uint32_t index, - std::string_view name, Kind kind, uint32_t elementTypeId, - uint32_t indexTypeId, uint32_t numOfElements) - : Type(types, index, name, kind), - elementTypeId_(elementTypeId), - indexTypeId_(indexTypeId), - numOfElements_(numOfElements) {} - uint32_t GetElementTypeId() const { return elementTypeId_; } - uint32_t GetIndexTypeId() const { return indexTypeId_; } - uint32_t GetNumberOfElements() const { return numOfElements_; } - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; - - private: +class Array : public Type +{ +public: + Array(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, + std::string_view name, + Kind kind, + uint32_t elementTypeId, + uint32_t indexTypeId, + uint32_t numOfElements) + : Type(types, index, name, kind), + elementTypeId_(elementTypeId), + indexTypeId_(indexTypeId), + numOfElements_(numOfElements) + { + } + uint32_t + GetElementTypeId() const + { + return elementTypeId_; + } + uint32_t + GetIndexTypeId() const + { + return indexTypeId_; + } + uint32_t + GetNumberOfElements() const + { + return numOfElements_; + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; + +private: const uint32_t elementTypeId_; const uint32_t indexTypeId_; const uint32_t numOfElements_; }; -class StructUnion : public Type { - public: - StructUnion(const std::vector<std::unique_ptr<Type>> &types, - uint32_t index, std::string_view name, Kind kind, - uint32_t bytesize, std::map<std::string, Member> members) - : Type(types, index, name, kind), - bytesize_(bytesize), - members_(members) {} - uint32_t GetByteSize() const { return bytesize_; } - const std::map<std::string, Member> &GetMembers() const { return members_; } - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; - - private: +class StructUnion : public Type +{ +public: + StructUnion(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, + std::string_view name, + Kind kind, + uint32_t bytesize, + std::map<std::string, Member> members) + : Type(types, index, name, kind), bytesize_(bytesize), members_(members) + { + } + uint32_t + GetByteSize() const + { + return bytesize_; + } + const std::map<std::string, Member>& + GetMembers() const + { + return members_; + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; + +private: const uint32_t bytesize_; const std::map<std::string, Member> members_; }; -class Enumeration : public Type { - public: - Enumeration(const std::vector<std::unique_ptr<Type>> &types, - uint32_t index, std::string_view name, Kind kind, - uint32_t bytesize, std::map<std::string, int> enumerators) - : Type(types, index, name, kind), - bytesize_(bytesize), - enumerators_(enumerators) {} - uint32_t GetByteSize() const { return bytesize_; } - const std::map<std::string, int> &GetEnums() const { return enumerators_; } - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; - - private: +class Enumeration : public Type +{ +public: + Enumeration(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, + std::string_view name, + Kind kind, + uint32_t bytesize, + std::map<std::string, int> enumerators) + : Type(types, index, name, kind), + bytesize_(bytesize), + enumerators_(enumerators) + { + } + uint32_t + GetByteSize() const + { + return bytesize_; + } + const std::map<std::string, int>& + GetEnums() const + { + return enumerators_; + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; + +private: const uint32_t bytesize_; const std::map<std::string, int> enumerators_; }; -// BTF only considers structs and unions as forward-declared types, and does not -// include forward-declared enums. They are treated as BTF_KIND_ENUMs with vlen -// set to zero -class ForwardDeclaration : public Type { - public: - ForwardDeclaration(const std::vector<std::unique_ptr<Type>> &types, - uint32_t index, std::string_view name, Kind kind, - bool isUnion) - : Type(types, index, name, kind), - fwdKind_(isUnion ? ForwardDeclarationKind::UNION - : ForwardDeclarationKind::STRUCT) {} - ForwardDeclarationKind GetFwdKind() const { return fwdKind_; } - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; - - private: +// BTF only considers structs and unions as forward-declared types, and does +// not include forward-declared enums. They are treated as BTF_KIND_ENUMs with +// vlen set to zero +class ForwardDeclaration : public Type +{ +public: + ForwardDeclaration(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, + std::string_view name, + Kind kind, + bool isUnion) + : Type(types, index, name, kind), + fwdKind_(isUnion ? ForwardDeclarationKind::UNION + : ForwardDeclarationKind::STRUCT) + { + } + ForwardDeclarationKind + GetFwdKind() const + { + return fwdKind_; + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; + +private: const ForwardDeclarationKind fwdKind_; }; -class Function : public Type { - public: - enum class Linkage : uint16_t { STATIC, GLOBAL, EXTERN }; - Function(const std::vector<std::unique_ptr<Type>> &types, - uint32_t index, std::string_view name, Kind kind, - uint32_t referredTypeId, Linkage linkage) - : Type(types, index, name, kind), - referredTypeId_(referredTypeId), - linkage_(linkage) {} - uint32_t GetReferredTypeId() const { return referredTypeId_; } - Linkage GetLinkage() const { return linkage_; } - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; - - private: +class Function : public Type +{ +public: + enum class Linkage : uint16_t + { + STATIC, + GLOBAL, + EXTERN + }; + Function(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, + std::string_view name, + Kind kind, + uint32_t referredTypeId, + Linkage linkage) + : Type(types, index, name, kind), + referredTypeId_(referredTypeId), + linkage_(linkage) + { + } + uint32_t + GetReferredTypeId() const + { + return referredTypeId_; + } + Linkage + GetLinkage() const + { + return linkage_; + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; + +private: const uint32_t referredTypeId_; const Linkage linkage_; }; -class FunctionPrototype : public Type { - public: - FunctionPrototype(const std::vector<std::unique_ptr<Type>> &types, - uint32_t index, std::string_view name, Kind kind, - uint32_t returnTypeId, std::vector<Parameter> parameters) - : Type(types, index, name, kind), - returnTypeId_(returnTypeId), - parameters_(parameters) {} - uint32_t GetReturnTypeId() const { return returnTypeId_; } - const std::vector<Parameter> &GetParameters() const { return parameters_; } - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; - - private: +class FunctionPrototype : public Type +{ +public: + FunctionPrototype(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, + std::string_view name, + Kind kind, + uint32_t returnTypeId, + std::vector<Parameter> parameters) + : Type(types, index, name, kind), + returnTypeId_(returnTypeId), + parameters_(parameters) + { + } + uint32_t + GetReturnTypeId() const + { + return returnTypeId_; + } + const std::vector<Parameter>& + GetParameters() const + { + return parameters_; + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; + +private: const uint32_t returnTypeId_; const std::vector<Parameter> parameters_; }; -class Variable : public Type { - public: - enum class Linkage : uint32_t { STATIC, GLOBAL_ALLOC, GLOBAL_EXTERN }; - Variable(const std::vector<std::unique_ptr<Type>> &types, - uint32_t index, std::string_view name, Kind kind, - unsigned varTypeId, Linkage linkage) - : Type(types, index, name, kind), - varTypeId_(varTypeId), - linkage_(linkage) {} - uint32_t GetVarTypeId() const { return varTypeId_; } - Linkage GetLinkage() const { return linkage_; } - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; - - private: +class Variable : public Type +{ +public: + enum class Linkage : uint32_t + { + STATIC, + GLOBAL_ALLOC, + GLOBAL_EXTERN + }; + Variable(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, + std::string_view name, + Kind kind, + unsigned varTypeId, + Linkage linkage) + : Type(types, index, name, kind), varTypeId_(varTypeId), linkage_(linkage) + { + } + uint32_t + GetVarTypeId() const + { + return varTypeId_; + } + Linkage + GetLinkage() const + { + return linkage_; + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; + +private: const uint32_t varTypeId_; const Linkage linkage_; }; -class DataSection : public Type { - public: - DataSection(const std::vector<std::unique_ptr<Type>> &types, - uint32_t index, std::string_view name, Kind kind, - uint32_t bytesize, std::vector<Secinfo> secinfos) - : Type(types, index, name, kind), - bytesize_(bytesize), - secinfos_(secinfos) {} - uint32_t GetByteSize() const { return bytesize_; } - const std::vector<Secinfo> &GetSecinfos() const { return secinfos_; } - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; - - private: +class DataSection : public Type +{ +public: + DataSection(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, + std::string_view name, + Kind kind, + uint32_t bytesize, + std::vector<Secinfo> secinfos) + : Type(types, index, name, kind), bytesize_(bytesize), secinfos_(secinfos) + { + } + uint32_t + GetByteSize() const + { + return bytesize_; + } + const std::vector<Secinfo>& + GetSecinfos() const + { + return secinfos_; + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; + +private: const uint32_t bytesize_; const std::vector<Secinfo> secinfos_; }; // Not actually a BTF type but needed for uniformity of representation. -class ElfSymbol : public Type { - public: - ElfSymbol(const std::vector<std::unique_ptr<Type>> &types, - abigail::elf_symbol_sptr symbol, uint32_t type_id) - : Type(types, -1, {}, -1), symbol_(symbol), type_id_(type_id) {} - abigail::elf_symbol_sptr GetElfSymbol() const { return symbol_; } - uint32_t GetTypeId() const { return type_id_; } - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; - - private: +class ElfSymbol : public Type +{ +public: + ElfSymbol(const std::vector<std::unique_ptr<Type>>& types, + abigail::elf_symbol_sptr symbol, + uint32_t type_id) + : Type(types, -1, {}, -1), symbol_(symbol), type_id_(type_id) + { + } + abigail::elf_symbol_sptr + GetElfSymbol() const + { + return symbol_; + } + uint32_t + GetTypeId() const + { + return type_id_; + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; + +private: abigail::elf_symbol_sptr symbol_; uint32_t type_id_; }; -std::ostream &operator<<(std::ostream &os, const Type &bt); -std::ostream &operator<<(std::ostream &os, const Ptr &bp); -std::ostream &operator<<(std::ostream &os, const Typedef &bp); -std::ostream &operator<<(std::ostream &os, const Qualifier &bp); -std::ostream &operator<<(std::ostream &os, const Integer &bi); -std::ostream &operator<<(std::ostream &os, const Array &ba); -std::ostream &operator<<(std::ostream &os, const StructUnion &bsu); -std::ostream &operator<<(std::ostream &os, const Enumeration &be); -std::ostream &operator<<(std::ostream &os, const ForwardDeclaration &bfd); -std::ostream &operator<<(std::ostream &os, const Function &bf); -std::ostream &operator<<(std::ostream &os, const FunctionPrototype &bfp); -std::ostream &operator<<(std::ostream &os, const Variable &bv); -std::ostream &operator<<(std::ostream &os, const DataSection &bds); -std::ostream &operator<<(std::ostream &os, const ElfSymbol &bes); -std::ostream &operator<<(std::ostream &os, Variable::Linkage linkage); -std::ostream &operator<<(std::ostream &os, Function::Linkage linkage); +std::ostream& +operator<<(std::ostream& os, const Type& bt); +std::ostream& +operator<<(std::ostream& os, const Ptr& bp); +std::ostream& +operator<<(std::ostream& os, const Typedef& bp); +std::ostream& +operator<<(std::ostream& os, const Qualifier& bp); +std::ostream& +operator<<(std::ostream& os, const Integer& bi); +std::ostream& +operator<<(std::ostream& os, const Array& ba); +std::ostream& +operator<<(std::ostream& os, const StructUnion& bsu); +std::ostream& +operator<<(std::ostream& os, const Enumeration& be); +std::ostream& +operator<<(std::ostream& os, const ForwardDeclaration& bfd); +std::ostream& +operator<<(std::ostream& os, const Function& bf); +std::ostream& +operator<<(std::ostream& os, const FunctionPrototype& bfp); +std::ostream& +operator<<(std::ostream& os, const Variable& bv); +std::ostream& +operator<<(std::ostream& os, const DataSection& bds); +std::ostream& +operator<<(std::ostream& os, const ElfSymbol& bes); +std::ostream& +operator<<(std::ostream& os, Variable::Linkage linkage); +std::ostream& +operator<<(std::ostream& os, Function::Linkage linkage); // BTF Specification: https://www.kernel.org/doc/html/latest/bpf/btf.html -class Structs { - public: - Structs(const char *start, std::unique_ptr<abigail::ir::environment> env, - const abigail::symtab_reader::symtab_sptr tab, - const bool verbose = false); +class Structs +{ +public: + Structs(const char* start, + std::unique_ptr<abigail::ir::environment> env, + const abigail::symtab_reader::symtab_sptr tab, + const bool verbose = false); ~Structs() = default; - void PrintHeader(); - void BuildTypes(); - void PrintStringSection(); - const std::map<std::string_view, const Type *const> &GetSymbols( - bool use_elf_symbols) const { + void + PrintHeader(); + void + BuildTypes(); + void + PrintStringSection(); + const std::map<std::string_view, const Type* const>& + GetSymbols(bool use_elf_symbols) const + { return use_elf_symbols ? elf_symbols_ : btf_symbols_; } - private: - const btf_header *header_; - const btf_type *type_section_; - const char *str_section_; +private: + const btf_header* header_; + const btf_type* type_section_; + const char* str_section_; const std::unique_ptr<abigail::ir::environment> env_; const abigail::symtab_reader::symtab_sptr tab_; const bool verbose_; std::vector<std::unique_ptr<Type>> types_; std::unordered_map<std::string_view, uint32_t> btf_symbol_types_; - std::map<std::string_view, const Type *const> btf_symbols_; - std::map<std::string_view, const Type *const> elf_symbols_; + std::map<std::string_view, const Type* const> btf_symbols_; + std::map<std::string_view, const Type* const> elf_symbols_; std::vector<std::string> bad_names_; std::string bad_prefix_1_; std::string bad_prefix_2_; - int BuildOneType(const btf_type *t, uint32_t index); - void BuildElfSymbols(); - std::map<std::string, Member> BuildMembers( - bool kflag, const btf_member *members, size_t vlen); - std::map<std::string, int> BuildEnums(const struct btf_enum *enums, - size_t vlen); - std::vector<Parameter> BuildParams(const struct btf_param *params, - size_t vlen); - std::vector<Secinfo> BuildDatasec(const btf_type *type, size_t vlen); - std::string_view GetName(uint32_t name_off); + int + BuildOneType(const btf_type* t, uint32_t index); + void + BuildElfSymbols(); + std::map<std::string, Member> + BuildMembers(bool kflag, const btf_member* members, size_t vlen); + std::map<std::string, int> + BuildEnums(const struct btf_enum* enums, size_t vlen); + std::vector<Parameter> + BuildParams(const struct btf_param* params, size_t vlen); + std::vector<Secinfo> + BuildDatasec(const btf_type* type, size_t vlen); + std::string_view + GetName(uint32_t name_off); }; -Structs ReadFile(const std::string &path, bool verbose = false); +Structs +ReadFile(const std::string& path, bool verbose = false); -} // end namespace btf -} // end namespace abigail +} // end namespace btf +} // end namespace abigail -#endif // __ABG_BTF_H__ +#endif // __ABG_BTF_H__ diff --git a/include/abg-scc.h b/include/abg-scc.h index d60b1aed..c152def0 100644 --- a/include/abg-scc.h +++ b/include/abg-scc.h @@ -14,7 +14,8 @@ #include <optional> #include <vector> -namespace abigail { +namespace abigail +{ /* * This is a streamlined Strongly-Connected Component finder for use with @@ -59,26 +60,33 @@ namespace abigail { * the nodes as visited), this should be done now. Otherwise, an empty vector * will be returned. */ -template<typename Node> class SCC { - public: - explicit SCC(std::function<bool(const Node &, const Node &)> cmp) : cmp_(cmp) - {} - ~SCC() { +template <typename Node> class SCC +{ +public: + explicit SCC(std::function<bool(const Node&, const Node&)> cmp) : cmp_(cmp) + { + } + ~SCC() + { assert(open_.empty()); assert(root_index_.empty()); } - std::optional<size_t> Open(const Node &node) { - for (size_t ix = 0; ix < open_.size(); ++ix) { - const auto &other = open_[ix]; - // node == other? - if (!cmp_(node, other) && !cmp_(other, node)) { - // Pop indices to nodes which cannot be the root of their SCC. - while (root_index_.back() > ix) - root_index_.pop_back(); - return {}; + std::optional<size_t> + Open(const Node& node) + { + for (size_t ix = 0; ix < open_.size(); ++ix) + { + const auto& other = open_[ix]; + // node == other? + if (!cmp_(node, other) && !cmp_(other, node)) + { + // Pop indices to nodes which cannot be the root of their SCC. + while (root_index_.back() > ix) + root_index_.pop_back(); + return {}; + } } - } // Unvisited, mark node as open and record root index. auto ix = open_.size(); open_.push_back(node); @@ -86,26 +94,29 @@ template<typename Node> class SCC { return ix; } - std::vector<Node> Close( - size_t ix, std::function<void(Node &)> update = [](Node &){}) { + std::vector<Node> + Close( + size_t ix, std::function<void(Node&)> update = [](Node&) {}) + { std::vector<Node> scc; assert(ix < open_.size()); update(open_[ix]); - if (ix == root_index_.back()) { - // Close SCC. - root_index_.pop_back(); - std::move(open_.begin() + ix, open_.end(), std::back_inserter(scc)); - open_.resize(ix); - } + if (ix == root_index_.back()) + { + // Close SCC. + root_index_.pop_back(); + std::move(open_.begin() + ix, open_.end(), std::back_inserter(scc)); + open_.resize(ix); + } return scc; } - private: - std::function<bool(const Node &, const Node &)> cmp_; +private: + std::function<bool(const Node&, const Node&)> cmp_; std::vector<Node> open_; std::vector<size_t> root_index_; }; -} // namespace abigail +} // namespace abigail -#endif // __ABG_SCC_H__ +#endif // __ABG_SCC_H__ diff --git a/src/abg-btf.cc b/src/abg-btf.cc index 8e4f9ea6..6da52d5c 100644 --- a/src/abg-btf.cc +++ b/src/abg-btf.cc @@ -20,63 +20,62 @@ #include "abg-btf.h" -namespace abigail { -namespace btf { +namespace abigail +{ +namespace btf +{ // This is a helper map that yields the name of a Type in the preferred // print style by indexing into the vector with a Kind static constexpr std::array<std::string_view, 16> kKindNames = { - "void type", - "integer type", - "pointer type", - "array type", - "struct type", - "union type", - "enum type", - "forward declaration", - "typedef", - "volatile", - "const", - "restrict", - "function", - "function type", - "variable", - "data section" -}; + "void type", + "integer type", + "pointer type", + "array type", + "struct type", + "union type", + "enum type", + "forward declaration", + "typedef", + "volatile", + "const", + "restrict", + "function", + "function type", + "variable", + "data section"}; // This matches bpftool dump format raw. static constexpr std::array<std::string_view, 16> kRawKindNames = { - "VOID", - "INT", - "PTR", - "ARRAY", - "STRUCT", - "UNION", - "ENUM", - "FWD", - "TYPEDEF", - "VOLATILE", - "CONST", - "RESTRICT", - "FUNC", - "FUNC_PROTO", - "VAR", - "DATASEC" -}; + "VOID", + "INT", + "PTR", + "ARRAY", + "STRUCT", + "UNION", + "ENUM", + "FWD", + "TYPEDEF", + "VOLATILE", + "CONST", + "RESTRICT", + "FUNC", + "FUNC_PROTO", + "VAR", + "DATASEC"}; static constexpr std::array<std::string_view, 3> kVarLinkage = { - "static", - "global-alloc", - "global-extern" // NOTE: bpftool currently says "(unknown)" + "static", + "global-alloc", + "global-extern" // NOTE: bpftool currently says "(unknown)" }; static constexpr std::array<std::string_view, 3> kFunLinkage = { - "static", - "global", - "extern" -}; + "static", "global", "extern"}; -Name Name::Add(Side side, Precedence precedence, std::string_view text) const { +Name +Name::Add(Side side, Precedence precedence, std::string_view text) const +{ bool bracket = precedence < precedence_; std::ostringstream left; std::ostringstream right; @@ -98,32 +97,43 @@ Name Name::Add(Side side, Precedence precedence, std::string_view text) const { return Name{left.str(), precedence, right.str()}; } -Name Name::Qualify(const std::set<Kind> &qualifiers) const { +Name +Name::Qualify(const std::set<Kind>& qualifiers) const +{ // this covers the case when bad qualifiers have been dropped if (qualifiers.empty()) return *this; // add qualifiers to the left or right of the type stem std::ostringstream os; - if (precedence_ == Precedence::NIL) { - for (const auto &qualifier : qualifiers) - os << kKindNames[qualifier] << ' '; - os << left_; - } else if (precedence_ == Precedence::POINTER) { - os << left_; - for (const auto &qualifier : qualifiers) - os << ' ' << kKindNames[qualifier]; - } else { - m_assert(false, "unqualifiable element"); - } + if (precedence_ == Precedence::NIL) + { + for (const auto& qualifier : qualifiers) + os << kKindNames[qualifier] << ' '; + os << left_; + } + else if (precedence_ == Precedence::POINTER) + { + os << left_; + for (const auto& qualifier : qualifiers) + os << ' ' << kKindNames[qualifier]; + } + else + { + m_assert(false, "unqualifiable element"); + } // qualifiers attach without affecting precedence return Name{os.str(), precedence_, right_}; } -std::ostream &Name::Print(std::ostream &os) const { +std::ostream& +Name::Print(std::ostream& os) const +{ return os << left_ << right_; } -std::ostream &operator<<(std::ostream &os, const Name &name) { +std::ostream& +operator<<(std::ostream& os, const Name& name) +{ return name.Print(os); } @@ -132,47 +142,57 @@ std::ostream &operator<<(std::ostream &os, const Name &name) { // 2. Qualifiers need to be placed according to what they qualify. // 3. The BTF model doesn't preclude ordering and duplication issues. // 4. A better model would have qualifiers as part of the types. -const Name &Type::GetDescription(NameCache &names) const { +const Name& +Type::GetDescription(NameCache& names) const +{ // infinite recursion prevention - insert at most once static const Name black_hole{"#"}; auto insertion = names.insert({this, black_hole}); - Name &cached = insertion.first->second; - - if (insertion.second) { - // newly inserted, need to determine name of type - std::set<Kind> qualifiers; - const Type &under = ResolveQualifiers(qualifiers); - if (this == &under) { - // unqualified, simple case - cached = MakeDescription(names); - } else { - // qualified, but we may end up adding no qualifiers - auto insertion_under = names.insert({&under, black_hole}); - Name &cached_under = insertion_under.first->second; - - // newly inserted underlying type name - if (insertion_under.second) - cached_under = under.MakeDescription(names); - - // add the qualifiers (to the appropriate side) - cached = cached_under.Qualify(qualifiers); + Name& cached = insertion.first->second; + + if (insertion.second) + { + // newly inserted, need to determine name of type + std::set<Kind> qualifiers; + const Type& under = ResolveQualifiers(qualifiers); + if (this == &under) + { + // unqualified, simple case + cached = MakeDescription(names); + } + else + { + // qualified, but we may end up adding no qualifiers + auto insertion_under = names.insert({&under, black_hole}); + Name& cached_under = insertion_under.first->second; + + // newly inserted underlying type name + if (insertion_under.second) + cached_under = under.MakeDescription(names); + + // add the qualifiers (to the appropriate side) + cached = cached_under.Qualify(qualifiers); + } } - } return cached; } -std::string GetPlainDescription(NameCache &names, const Type &type) { +std::string +GetPlainDescription(NameCache& names, const Type& type) +{ std::ostringstream os; os << '"' << type.GetDescription(names) << '"'; return os.str(); } -std::string GetTypedefDescription(NameCache &names, const Type &given) { +std::string +GetTypedefDescription(NameCache& names, const Type& given) +{ std::ostringstream os; std::vector<std::string_view> typedefs; - const Type &type = given.ResolveTypedef(typedefs); + const Type& type = given.ResolveTypedef(typedefs); for (auto td : typedefs) os << std::quoted(td) << " = "; os << GetPlainDescription(names, type); @@ -181,74 +201,99 @@ std::string GetTypedefDescription(NameCache &names, const Type &given) { constexpr size_t INDENT_INCREMENT = 2; -void Print(const Comparison &comparison, const Outcomes &outcomes, Seen &seen, - NameCache &names, std::ostream &os, size_t indent) { - const auto *lhs = comparison.first; - const auto *rhs = comparison.second; - if (!rhs) { - os << GetPlainDescription(names, *lhs) << " was removed\n"; - return; - } - if (!lhs) { - os << GetPlainDescription(names, *rhs) << " was added\n"; - return; - } - bool td = lhs->GetKind() == BTF_KIND_TYPEDEF - || rhs->GetKind() == BTF_KIND_TYPEDEF; +void +Print(const Comparison& comparison, + const Outcomes& outcomes, + Seen& seen, + NameCache& names, + std::ostream& os, + size_t indent) +{ + const auto* lhs = comparison.first; + const auto* rhs = comparison.second; + if (!rhs) + { + os << GetPlainDescription(names, *lhs) << " was removed\n"; + return; + } + if (!lhs) + { + os << GetPlainDescription(names, *rhs) << " was added\n"; + return; + } + bool td = + lhs->GetKind() == BTF_KIND_TYPEDEF || rhs->GetKind() == BTF_KIND_TYPEDEF; const std::string lhs_descr = td ? GetTypedefDescription(names, *lhs) - : GetPlainDescription(names, *lhs); + : GetPlainDescription(names, *lhs); const std::string rhs_descr = td ? GetTypedefDescription(names, *rhs) - : GetPlainDescription(names, *rhs); + : GetPlainDescription(names, *rhs); if (lhs_descr == rhs_descr) os << lhs_descr << " changed"; else os << "changed from " << lhs_descr << " to " << rhs_descr; - const auto &details = outcomes.find(comparison)->second; + const auto& details = outcomes.find(comparison)->second; auto insertion = seen.insert({comparison, false}); - if (!insertion.second) { - if (!insertion.first->second) - os << " (being reported)"; - else if (!details.empty()) - os << " (already reported)"; - } + if (!insertion.second) + { + if (!insertion.first->second) + os << " (being reported)"; + else if (!details.empty()) + os << " (already reported)"; + } os << '\n'; - if (insertion.second) { - Print(details, outcomes, seen, names, os, indent + INDENT_INCREMENT); - insertion.first->second = true; - } + if (insertion.second) + { + Print(details, outcomes, seen, names, os, indent + INDENT_INCREMENT); + insertion.first->second = true; + } // paragraph spacing if (!indent) os << '\n'; } -void Print(const Diff &details, const Outcomes &outcomes, Seen &seen, - NameCache &names, std::ostream &os, size_t indent) { - for (const auto &detail : details) { - os << std::string(indent, ' ') << detail.text_; - if (!detail.edge_) { - os << '\n'; - } else { - os << ' '; - Print(detail.edge_.value(), outcomes, seen, names, os, indent); +void +Print(const Diff& details, + const Outcomes& outcomes, + Seen& seen, + NameCache& names, + std::ostream& os, + size_t indent) +{ + for (const auto& detail : details) + { + os << std::string(indent, ' ') << detail.text_; + if (!detail.edge_) + { + os << '\n'; + } + else + { + os << ' '; + Print(detail.edge_.value(), outcomes, seen, names, os, indent); + } } - } } -const Type &Type::GetTypeAtIndex(size_t index) const { +const Type& +Type::GetTypeAtIndex(size_t index) const +{ m_assert(index < types_.size(), "Index out of bounds."); return *(types_[index].get()); } -std::string QualifiersMessage(Kind qualifier, const std::string &action) { +std::string +QualifiersMessage(Kind qualifier, const std::string& action) +{ std::ostringstream os; os << "qualifier " << kKindNames[qualifier] << ' ' << action; return os.str(); } -Result Type::CompareSymbols( - const std::map<std::string_view, const Type *const> &lhs, - const std::map<std::string_view, const Type *const> &rhs, - Outcomes &outcomes) { +Result +Type::CompareSymbols(const std::map<std::string_view, const Type* const>& lhs, + const std::map<std::string_view, const Type* const>& rhs, + Outcomes& outcomes) +{ Result result; State state(outcomes); auto lit = lhs.begin(); @@ -258,56 +303,76 @@ Result Type::CompareSymbols( // without BTF information may have changed type. // // NOTE: this currently happens for all global variables - while (lit != lhs.end() || rit != rhs.end()) { - if (rit == rhs.end() || (lit != lhs.end() && lit->first < rit->first)) { - // removed - if (lit->second) { - auto diff = Removed(*lit->second, state); - result.AddDiff("symbol", diff); - } else { - std::ostringstream os; - os << "symbol " << std::quoted(lit->first) - << " (of unknown type) was removed"; - result.AddDiff(os.str()); - } - ++lit; - } else if (lit == lhs.end() || (rit != rhs.end() && lit->first > rit->first)) { - // added - if (rit->second) { - auto diff = Added(*rit->second, state); - result.AddDiff("symbol", diff); - } else { - std::ostringstream os; - os << "symbol " << std::quoted(rit->first) - << " (if unknown type) was added"; - result.AddDiff(os.str()); - } - ++rit; - } else { - // in both - if (lit->second && rit->second) { - auto diff = Compare(*lit->second, *rit->second, state); - result.MaybeAddDiff("symbol", diff); - } else { - std::ostringstream os; - os << "symbol " << std::quoted(lit->first) - << " (of unknown type) may have changed"; - result.AddDiff(os.str()); - } - ++lit; - ++rit; + while (lit != lhs.end() || rit != rhs.end()) + { + if (rit == rhs.end() || (lit != lhs.end() && lit->first < rit->first)) + { + // removed + if (lit->second) + { + auto diff = Removed(*lit->second, state); + result.AddDiff("symbol", diff); + } + else + { + std::ostringstream os; + os << "symbol " << std::quoted(lit->first) + << " (of unknown type) was removed"; + result.AddDiff(os.str()); + } + ++lit; + } + else if (lit == lhs.end() + || (rit != rhs.end() && lit->first > rit->first)) + { + // added + if (rit->second) + { + auto diff = Added(*rit->second, state); + result.AddDiff("symbol", diff); + } + else + { + std::ostringstream os; + os << "symbol " << std::quoted(rit->first) + << " (if unknown type) was added"; + result.AddDiff(os.str()); + } + ++rit; + } + else + { + // in both + if (lit->second && rit->second) + { + auto diff = Compare(*lit->second, *rit->second, state); + result.MaybeAddDiff("symbol", diff); + } + else + { + std::ostringstream os; + os << "symbol " << std::quoted(lit->first) + << " (of unknown type) may have changed"; + result.AddDiff(os.str()); + } + ++lit; + ++rit; + } } - } return result; } -Comparison Type::Removed(const Type &lhs, State &state) { +Comparison +Type::Removed(const Type& lhs, State& state) +{ Comparison comparison{&lhs, nullptr}; state.outcomes.insert({comparison, {}}); return comparison; } -Comparison Type::Added(const Type &rhs, State &state) { +Comparison +Type::Added(const Type& rhs, State& state) +{ Comparison comparison{nullptr, &rhs}; state.outcomes.insert({comparison, {}}); return comparison; @@ -320,157 +385,196 @@ Comparison Type::Added(const Type &rhs, State &state) { * 1. equals = true; perhaps only tentative edge differences * 2. equals = false; at least one definitive node or edge difference * - * On the first visit to a node we can put a placeholder in, the equals value is - * irrelevant, the diff may contain local and edge differences. If an SCC + * On the first visit to a node we can put a placeholder in, the equals value + * is irrelevant, the diff may contain local and edge differences. If an SCC * contains only internal edge differences (and equivalently equals is true) * then the differences can all (eventually) be discarded. * * On exit from the first visit to a node, equals reflects the tree of - * comparisons below that node in the DFS and similarly, the diff graph starting - * from the node contains a subtree of this tree plus potentially edges to - * existing nodes to the side or below (already visited SCCs, sharing), or above - * (back links forming cycles). + * comparisons below that node in the DFS and similarly, the diff graph + * starting from the node contains a subtree of this tree plus potentially + * edges to existing nodes to the side or below (already visited SCCs, + * sharing), or above (back links forming cycles). * * When an SCC is closed, all equals implies deleting all diffs, any false * implies updating all to false. * * On subsequent visits to a node, there are 2 cases. The node is still open: - * return true and an edge diff. The node is closed, return the stored value and - * an edge diff. + * return true and an edge diff. The node is closed, return the stored value + * and an edge diff. */ -std::pair<bool, std::optional<Comparison>> Type::Compare( - const Type &lhs, const Type &rhs, Type::State &state) { +std::pair<bool, std::optional<Comparison>> +Type::Compare(const Type& lhs, const Type& rhs, Type::State& state) +{ Comparison comparison{&lhs, &rhs}; // 1. Check if the comparison has an already known result. - if (state.known_equal.count(comparison)) { - // Already visited and closed. Equal. - return {true, {}}; - } - if (state.outcomes.count(comparison)) { - // Already visited and closed. Different. - return {false, {comparison}}; - } + if (state.known_equal.count(comparison)) + { + // Already visited and closed. Equal. + return {true, {}}; + } + if (state.outcomes.count(comparison)) + { + // Already visited and closed. Different. + return {false, {comparison}}; + } // Either open or not visited at all // 2. Record node with Strongly-Connected Component finder. auto handle = state.scc.Open({comparison, {}}); - if (!handle) { - // Already open. - // - // Return a dummy true outcome and some tentative diffs. The diffs may end - // up not being used and, while it would be nice to be lazier, they encode - // all the cycling-breaking edges needed to recreate a full diff structure. - return {true, {comparison}}; - } + if (!handle) + { + // Already open. + // + // Return a dummy true outcome and some tentative diffs. The diffs may + // end up not being used and, while it would be nice to be lazier, they + // encode all the cycling-breaking edges needed to recreate a full diff + // structure. + return {true, {comparison}}; + } // Comparison opened, need to close it before returning. Result result; std::set<Kind> lhs_quals; std::set<Kind> rhs_quals; - const Type &l = lhs.ResolveQualifiers(lhs_quals); - const Type &r = rhs.ResolveQualifiers(rhs_quals); - if (!lhs_quals.empty() || !rhs_quals.empty()) { - // 3.1 Qualified type difference. - auto lit = lhs_quals.begin(); - auto rit = rhs_quals.begin(); - auto lend = lhs_quals.end(); - auto rend = rhs_quals.end(); - while (lit != lend || rit != rend) { - if (rit == rend || (lit != lend && *lit < *rit)) { - result.AddDiff(QualifiersMessage(*lit, "removed")); - ++lit; - } else if (lit == lend || (rit != rend && *lit > *rit)) { - result.AddDiff(QualifiersMessage(*rit, "added")); - ++rit; - } else { - ++lit; - ++rit; - } + const Type& l = lhs.ResolveQualifiers(lhs_quals); + const Type& r = rhs.ResolveQualifiers(rhs_quals); + if (!lhs_quals.empty() || !rhs_quals.empty()) + { + // 3.1 Qualified type difference. + auto lit = lhs_quals.begin(); + auto rit = rhs_quals.begin(); + auto lend = lhs_quals.end(); + auto rend = rhs_quals.end(); + while (lit != lend || rit != rend) + { + if (rit == rend || (lit != lend && *lit < *rit)) + { + result.AddDiff(QualifiersMessage(*lit, "removed")); + ++lit; + } + else if (lit == lend || (rit != rend && *lit > *rit)) + { + result.AddDiff(QualifiersMessage(*rit, "added")); + ++rit; + } + else + { + ++lit; + ++rit; + } + } + const auto comp = Compare(l, r, state); + result.MaybeAddDiff("underlying type", comp); + } + else if (l.GetKind() == BTF_KIND_TYPEDEF || r.GetKind() == BTF_KIND_TYPEDEF) + { + // 3.2 Typedef difference. + std::vector<std::string_view> l_typedefs; + std::vector<std::string_view> r_typedefs; + const Type& l_ref = l.ResolveTypedef(l_typedefs); + const Type& r_ref = r.ResolveTypedef(r_typedefs); + const auto comp = Compare(l_ref, r_ref, state); + result.MaybeAddDiff("via typedefs", comp); + } + else if (typeid(l) != typeid(r)) + { + // 4. Incomparable. + result.equals_ = false; + } + else + { + // 5. Actually compare with dynamic type dispatch. + result = l.Equals(r, state); } - const auto comp = Compare(l, r, state); - result.MaybeAddDiff("underlying type", comp); - } else if (l.GetKind() == BTF_KIND_TYPEDEF - || r.GetKind() == BTF_KIND_TYPEDEF) { - // 3.2 Typedef difference. - std::vector<std::string_view> l_typedefs; - std::vector<std::string_view> r_typedefs; - const Type &l_ref = l.ResolveTypedef(l_typedefs); - const Type &r_ref = r.ResolveTypedef(r_typedefs); - const auto comp = Compare(l_ref, r_ref, state); - result.MaybeAddDiff("via typedefs", comp); - } else if (typeid(l) != typeid(r)) { - // 4. Incomparable. - result.equals_ = false; - } else { - // 5. Actually compare with dynamic type dispatch. - result = l.Equals(r, state); - } // 6. Update result and check for a complete Strongly-Connected Component. - auto comparisons = state.scc.Close(handle.value(), - [&result](Outcomes::value_type &p) { - p.second = result.details_; - }); - if (!comparisons.empty()) { - // Closed SCC. - // - // Note that result now incorporates every inequality and difference in the - // SCC via the DFS spanning tree. - if (result.equals_) { - // Same. Record equalities. - for (auto &c : comparisons) - state.known_equal.insert(c.first); - return {true, {}}; - } else { - // Different. Record diffs. - state.outcomes.insert(std::make_move_iterator(comparisons.begin()), - std::make_move_iterator(comparisons.end())); + auto comparisons = + state.scc.Close(handle.value(), [&result](Outcomes::value_type& p) { + p.second = result.details_; + }); + if (!comparisons.empty()) + { + // Closed SCC. + // + // Note that result now incorporates every inequality and difference in + // the SCC via the DFS spanning tree. + if (result.equals_) + { + // Same. Record equalities. + for (auto& c : comparisons) + state.known_equal.insert(c.first); + return {true, {}}; + } + else + { + // Different. Record diffs. + state.outcomes.insert(std::make_move_iterator(comparisons.begin()), + std::make_move_iterator(comparisons.end())); + } } - } // Note that both equals and diff are tentative iff comparison is open. return {result.equals_, {comparison}}; } -Name Void::MakeDescription(NameCache &names) const { +Name +Void::MakeDescription(NameCache& names) const +{ return Name{"void"}; } -Name Ptr::MakeDescription(NameCache &names) const { - return GetTypeAtIndex(GetPointeeTypeId()).GetDescription(names).Add( - Side::LEFT, Precedence::POINTER, "*"); +Name +Ptr::MakeDescription(NameCache& names) const +{ + return GetTypeAtIndex(GetPointeeTypeId()) + .GetDescription(names) + .Add(Side::LEFT, Precedence::POINTER, "*"); } -Name Typedef::MakeDescription(NameCache &names) const { +Name +Typedef::MakeDescription(NameCache& names) const +{ return Name{GetName()}; } -Name Qualifier::MakeDescription(NameCache &names) const { - m_assert(false, "should not be called"); // NOLINT +Name +Qualifier::MakeDescription(NameCache& names) const +{ + m_assert(false, "should not be called"); // NOLINT return Name{GetName()}; } -Name Integer::MakeDescription(NameCache &names) const { +Name +Integer::MakeDescription(NameCache& names) const +{ return Name{GetName()}; } -Name Array::MakeDescription(NameCache &names) const { +Name +Array::MakeDescription(NameCache& names) const +{ std::ostringstream os; os << '[' << GetNumberOfElements() << ']'; - return GetTypeAtIndex(GetElementTypeId()).GetDescription(names).Add( - Side::RIGHT, Precedence::ARRAY_FUNCTION, os.str()); + return GetTypeAtIndex(GetElementTypeId()) + .GetDescription(names) + .Add(Side::RIGHT, Precedence::ARRAY_FUNCTION, os.str()); } -Name StructUnion::MakeDescription(NameCache &names) const { +Name +StructUnion::MakeDescription(NameCache& names) const +{ std::ostringstream os; - os << (GetKind() == BTF_KIND_STRUCT ? "struct" : "union") - << ' ' << (GetName().empty() ? "<anon>" : GetName()); + os << (GetKind() == BTF_KIND_STRUCT ? "struct" : "union") << ' ' + << (GetName().empty() ? "<anon>" : GetName()); return Name{os.str()}; } -Name Enumeration::MakeDescription(NameCache &names) const { +Name +Enumeration::MakeDescription(NameCache& names) const +{ std::ostringstream os; os << "enum " << (GetName().empty() ? "<anon>" : GetName()); if (GetEnums().empty()) @@ -478,499 +582,605 @@ Name Enumeration::MakeDescription(NameCache &names) const { return Name{os.str()}; } -Name ForwardDeclaration::MakeDescription(NameCache &names) const { +Name +ForwardDeclaration::MakeDescription(NameCache& names) const +{ std::ostringstream os; os << GetFwdKind() << ' ' << GetName() << "<incomplete>"; return Name{os.str()}; } -Name FunctionPrototype::MakeDescription(NameCache &names) const { +Name +FunctionPrototype::MakeDescription(NameCache& names) const +{ std::ostringstream os; os << '('; bool sep = false; - for (const auto &p : GetParameters()) { - if (sep) - os << ", "; - else - sep = true; - const auto &arg_descr = GetTypeAtIndex(p.typeId_).GetDescription(names); - if (p.name_.empty()) - os << arg_descr; - else - os << arg_descr.Add(Side::LEFT, Precedence::ATOMIC, p.name_); - } + for (const auto& p : GetParameters()) + { + if (sep) + os << ", "; + else + sep = true; + const auto& arg_descr = GetTypeAtIndex(p.typeId_).GetDescription(names); + if (p.name_.empty()) + os << arg_descr; + else + os << arg_descr.Add(Side::LEFT, Precedence::ATOMIC, p.name_); + } os << ')'; - return GetTypeAtIndex(GetReturnTypeId()).GetDescription(names).Add( - Side::RIGHT, Precedence::ARRAY_FUNCTION, os.str()); + return GetTypeAtIndex(GetReturnTypeId()) + .GetDescription(names) + .Add(Side::RIGHT, Precedence::ARRAY_FUNCTION, os.str()); } -Name Variable::MakeDescription(NameCache &names) const { - return GetTypeAtIndex(GetVarTypeId()).GetDescription(names).Add( - Side::LEFT, Precedence::ATOMIC, GetName()); +Name +Variable::MakeDescription(NameCache& names) const +{ + return GetTypeAtIndex(GetVarTypeId()) + .GetDescription(names) + .Add(Side::LEFT, Precedence::ATOMIC, GetName()); } -Name Function::MakeDescription(NameCache &names) const { - return GetTypeAtIndex(GetReferredTypeId()).GetDescription(names).Add( - Side::LEFT, Precedence::ATOMIC, GetName()); +Name +Function::MakeDescription(NameCache& names) const +{ + return GetTypeAtIndex(GetReferredTypeId()) + .GetDescription(names) + .Add(Side::LEFT, Precedence::ATOMIC, GetName()); } -Name DataSection::MakeDescription(NameCache &names) const { +Name +DataSection::MakeDescription(NameCache& names) const +{ // NOTE: not yet encountered in the wild return Name{"Unimplemented"}; } -Name ElfSymbol::MakeDescription(NameCache &names) const { +Name +ElfSymbol::MakeDescription(NameCache& names) const +{ return Name{symbol_->get_name()}; } -Result Void::Equals(const Type &other, State &state) const { +Result +Void::Equals(const Type& other, State& state) const +{ return {}; } -Result Ptr::Equals(const Type &other, State &state) const { +Result +Ptr::Equals(const Type& other, State& state) const +{ Result result; - const auto &o = other.as<Ptr>(); + const auto& o = other.as<Ptr>(); const auto ref_diff = Compare(GetTypeAtIndex(GetPointeeTypeId()), - o.GetTypeAtIndex(o.GetPointeeTypeId()), state); + o.GetTypeAtIndex(o.GetPointeeTypeId()), + state); result.MaybeAddDiff("pointed-to type", ref_diff); return result; } -Result Typedef::Equals(const Type &other, State &state) const { - m_assert(false, "should not be called"); // NOLINT +Result +Typedef::Equals(const Type& other, State& state) const +{ + m_assert(false, "should not be called"); // NOLINT return {}; } -Result Qualifier::Equals(const Type &other, State &state) const { - m_assert(false, "should not be called"); // NOLINT +Result +Qualifier::Equals(const Type& other, State& state) const +{ + m_assert(false, "should not be called"); // NOLINT return {}; } -Result Integer::Equals(const Type &other, State &state) const { +Result +Integer::Equals(const Type& other, State& state) const +{ Result result; - const auto &o = other.as<Integer>(); + const auto& o = other.as<Integer>(); - if (isBool() != o.isBool()) { - result.AddDiff(isBool() ? "the first one is a boolean" - : "the second one is a boolean"); - } - if (isSigned() != o.isSigned()) { - result.AddDiff(isSigned() ? "the first one is signed" - : "the second one is signed"); - } - if (isChar() != o.isChar()) { - result.AddDiff(isChar() ? "the first one is a char" - : "the second one is a char"); - } + if (isBool() != o.isBool()) + { + result.AddDiff(isBool() ? "the first one is a boolean" + : "the second one is a boolean"); + } + if (isSigned() != o.isSigned()) + { + result.AddDiff(isSigned() ? "the first one is signed" + : "the second one is signed"); + } + if (isChar() != o.isChar()) + { + result.AddDiff(isChar() ? "the first one is a char" + : "the second one is a char"); + } result.MaybeAddDiff("offset", GetOffset(), o.GetOffset()); result.MaybeAddDiff("bit size", GetBitSize(), o.GetBitSize()); - if (GetBitSize() != GetByteSize() * 8 && - o.GetBitSize() != o.GetByteSize() * 8) + if (GetBitSize() != GetByteSize() * 8 + && o.GetBitSize() != o.GetByteSize() * 8) result.MaybeAddDiff("byte size", GetByteSize(), o.GetByteSize()); return result; } -Result Array::Equals(const Type &other, State &state) const { +Result +Array::Equals(const Type& other, State& state) const +{ Result result; - const auto &o = other.as<Array>(); + const auto& o = other.as<Array>(); - result.MaybeAddDiff("number of elements", - GetNumberOfElements(), o.GetNumberOfElements()); - const auto index_type_diff = - Compare(GetTypeAtIndex(GetIndexTypeId()), - o.GetTypeAtIndex(o.GetIndexTypeId()), state); + result.MaybeAddDiff( + "number of elements", GetNumberOfElements(), o.GetNumberOfElements()); + const auto index_type_diff = Compare(GetTypeAtIndex(GetIndexTypeId()), + o.GetTypeAtIndex(o.GetIndexTypeId()), + state); result.MaybeAddDiff("index type", index_type_diff); const auto element_type_diff = Compare(GetTypeAtIndex(GetElementTypeId()), - o.GetTypeAtIndex(o.GetElementTypeId()), state); + o.GetTypeAtIndex(o.GetElementTypeId()), + state); result.MaybeAddDiff("element type", element_type_diff); return result; } -Result StructUnion::Equals(const Type &other, State &state) const { +Result +StructUnion::Equals(const Type& other, State& state) const +{ Result result; - const auto &o = other.as<StructUnion>(); + const auto& o = other.as<StructUnion>(); - if (GetKind() != o.GetKind()) { - result.AddDiff(GetKind() == BTF_KIND_STRUCT - ? "changed from struct to union" - : "changed from union to struct"); - } + if (GetKind() != o.GetKind()) + { + result.AddDiff(GetKind() == BTF_KIND_STRUCT + ? "changed from struct to union" + : "changed from union to struct"); + } result.MaybeAddDiff("byte size", GetByteSize(), o.GetByteSize()); - const auto &members1 = GetMembers(); - const auto &members2 = o.GetMembers(); + const auto& members1 = GetMembers(); + const auto& members2 = o.GetMembers(); std::set<std::string> visited_members; - for (const auto &m1 : members1) { - visited_members.insert(m1.first); - auto iter = members2.find(m1.first); - if (iter == members2.end()) { - std::ostringstream os; - os << "member " << std::quoted(m1.first) << " of type"; - auto diff = Removed(GetTypeAtIndex(m1.second.typeId_), state); - result.AddDiff(os.str(), diff); - } else { - result.MaybeAddDiff([&](std::ostream &os) { - os << "member " << std::quoted(m1.first) << " offset"; - }, m1.second.offset_, iter->second.offset_); - result.MaybeAddDiff([&](std::ostream &os) { - os << "member " << std::quoted(m1.first) << " bitfield size"; - }, m1.second.bitfieldSize_, iter->second.bitfieldSize_); - const auto sub_diff = - Compare(GetTypeAtIndex(m1.second.typeId_), - o.GetTypeAtIndex(iter->second.typeId_), state); - result.MaybeAddDiff([&](std::ostream &os) { - os << "member " << std::quoted(m1.first) << " type"; - }, sub_diff); + for (const auto& m1 : members1) + { + visited_members.insert(m1.first); + auto iter = members2.find(m1.first); + if (iter == members2.end()) + { + std::ostringstream os; + os << "member " << std::quoted(m1.first) << " of type"; + auto diff = Removed(GetTypeAtIndex(m1.second.typeId_), state); + result.AddDiff(os.str(), diff); + } + else + { + result.MaybeAddDiff( + [&](std::ostream& os) { + os << "member " << std::quoted(m1.first) << " offset"; + }, + m1.second.offset_, + iter->second.offset_); + result.MaybeAddDiff( + [&](std::ostream& os) { + os << "member " << std::quoted(m1.first) << " bitfield size"; + }, + m1.second.bitfieldSize_, + iter->second.bitfieldSize_); + const auto sub_diff = Compare(GetTypeAtIndex(m1.second.typeId_), + o.GetTypeAtIndex(iter->second.typeId_), + state); + result.MaybeAddDiff( + [&](std::ostream& os) { + os << "member " << std::quoted(m1.first) << " type"; + }, + sub_diff); + } } - } - for (const auto &m2 : members2) { - if (visited_members.find(m2.first) == visited_members.end()) { - std::ostringstream os; - os << "member " << std::quoted(m2.first) << " of type"; - auto diff = Added(o.GetTypeAtIndex(m2.second.typeId_), state); - result.AddDiff(os.str(), diff); + for (const auto& m2 : members2) + { + if (visited_members.find(m2.first) == visited_members.end()) + { + std::ostringstream os; + os << "member " << std::quoted(m2.first) << " of type"; + auto diff = Added(o.GetTypeAtIndex(m2.second.typeId_), state); + result.AddDiff(os.str(), diff); + } } - } return result; } -Result Enumeration::Equals(const Type &other, State &state) const { +Result +Enumeration::Equals(const Type& other, State& state) const +{ Result result; - const auto &o = other.as<Enumeration>(); + const auto& o = other.as<Enumeration>(); result.MaybeAddDiff("byte size", GetByteSize(), o.GetByteSize()); - const auto &enums1 = GetEnums(); - const auto &enums2 = o.GetEnums(); + const auto& enums1 = GetEnums(); + const auto& enums2 = o.GetEnums(); std::set<std::string> visited_enums; - for (const auto &e1 : enums1) { - visited_enums.insert(e1.first); - auto iter = enums2.find(e1.first); - if (iter == enums2.end()) { - std::ostringstream os; - os << "enumerator " << std::quoted(e1.first) - << " (" << e1.second << ") was removed"; - result.AddDiff(os.str()); - } else { - result.MaybeAddDiff([&](std::ostream &os) { - os << "enumerator " << std::quoted(e1.first) << " value"; - }, e1.second, iter->second); + for (const auto& e1 : enums1) + { + visited_enums.insert(e1.first); + auto iter = enums2.find(e1.first); + if (iter == enums2.end()) + { + std::ostringstream os; + os << "enumerator " << std::quoted(e1.first) << " (" << e1.second + << ") was removed"; + result.AddDiff(os.str()); + } + else + { + result.MaybeAddDiff( + [&](std::ostream& os) { + os << "enumerator " << std::quoted(e1.first) << " value"; + }, + e1.second, + iter->second); + } } - } - for (const auto &e2 : enums2) { - if (visited_enums.find(e2.first) == visited_enums.end()) { - std::ostringstream os; - os << "enumerator " << std::quoted(e2.first) - << " (" << e2.second << ") was added"; - result.AddDiff(os.str()); + for (const auto& e2 : enums2) + { + if (visited_enums.find(e2.first) == visited_enums.end()) + { + std::ostringstream os; + os << "enumerator " << std::quoted(e2.first) << " (" << e2.second + << ") was added"; + result.AddDiff(os.str()); + } } - } return result; } -Result ForwardDeclaration::Equals(const Type &other, State &state) const { +Result +ForwardDeclaration::Equals(const Type& other, State& state) const +{ Result result; - const auto &o = other.as<ForwardDeclaration>(); + const auto& o = other.as<ForwardDeclaration>(); result.MaybeAddDiff("kind", GetFwdKind(), o.GetFwdKind()); return result; } -Result Function::Equals(const Type &other, State &state) const { +Result +Function::Equals(const Type& other, State& state) const +{ Result result; - const auto &o = other.as<Function>(); + const auto& o = other.as<Function>(); result.MaybeAddDiff("linkage", GetLinkage(), o.GetLinkage()); - const auto func_proto_diff = - Compare(GetTypeAtIndex(GetReferredTypeId()), - o.GetTypeAtIndex(o.GetReferredTypeId()), state); + const auto func_proto_diff = Compare(GetTypeAtIndex(GetReferredTypeId()), + o.GetTypeAtIndex(o.GetReferredTypeId()), + state); result.MaybeAddDiff("type", func_proto_diff); return result; } -Result FunctionPrototype::Equals(const Type &other, State &state) const { +Result +FunctionPrototype::Equals(const Type& other, State& state) const +{ Result result; - const auto &o = other.as<FunctionPrototype>(); + const auto& o = other.as<FunctionPrototype>(); - const auto return_type_diff = - Compare(GetTypeAtIndex(GetReturnTypeId()), - o.GetTypeAtIndex(o.GetReturnTypeId()), state); + const auto return_type_diff = Compare(GetTypeAtIndex(GetReturnTypeId()), + o.GetTypeAtIndex(o.GetReturnTypeId()), + state); result.MaybeAddDiff("return type", return_type_diff); - const auto ¶meters1 = GetParameters(); - const auto ¶meters2 = o.GetParameters(); + const auto& parameters1 = GetParameters(); + const auto& parameters2 = o.GetParameters(); size_t min = std::min(parameters1.size(), parameters2.size()); - for (size_t i = 0; i < min; ++i) { - const auto &p1 = parameters1.at(i); - const auto &p2 = parameters2.at(i); - const auto sub_diff = Compare(GetTypeAtIndex(p1.typeId_), - o.GetTypeAtIndex(p2.typeId_), state); - result.MaybeAddDiff([&](std::ostream &os) { - os << "parameter " << i + 1; - const auto &n1 = p1.name_; - const auto &n2 = p2.name_; - if (n1 == n2 && !n1.empty()) { - os << " (" << std::quoted(n1) << ")"; - } else if (n1 != n2) { - os << " ("; - if (!n1.empty()) os << "was " << std::quoted(n1); - if (!n1.empty() && !n2.empty()) os << ", "; - if (!n2.empty()) os << "now " << std::quoted(n2); - os << ")"; - } - os << " type"; - }, sub_diff); - } + for (size_t i = 0; i < min; ++i) + { + const auto& p1 = parameters1.at(i); + const auto& p2 = parameters2.at(i); + const auto sub_diff = Compare( + GetTypeAtIndex(p1.typeId_), o.GetTypeAtIndex(p2.typeId_), state); + result.MaybeAddDiff( + [&](std::ostream& os) { + os << "parameter " << i + 1; + const auto& n1 = p1.name_; + const auto& n2 = p2.name_; + if (n1 == n2 && !n1.empty()) + { + os << " (" << std::quoted(n1) << ")"; + } + else if (n1 != n2) + { + os << " ("; + if (!n1.empty()) + os << "was " << std::quoted(n1); + if (!n1.empty() && !n2.empty()) + os << ", "; + if (!n2.empty()) + os << "now " << std::quoted(n2); + os << ")"; + } + os << " type"; + }, + sub_diff); + } bool added = parameters1.size() < parameters2.size(); - const auto ¶meters = added ? parameters2 : parameters1; - for (size_t i = min; i < parameters.size(); ++i) { - const auto ¶meter = parameters.at(i); - std::ostringstream os; - os << "parameter " << i + 1; - if (!parameter.name_.empty()) - os << " (" << std::quoted(parameter.name_) << ")"; - os << " of type"; - const auto ¶meter_type = GetTypeAtIndex(parameter.typeId_); - auto diff = added ? Added(parameter_type, state) - : Removed(parameter_type, state); - result.AddDiff(os.str(), diff); - } + const auto& parameters = added ? parameters2 : parameters1; + for (size_t i = min; i < parameters.size(); ++i) + { + const auto& parameter = parameters.at(i); + std::ostringstream os; + os << "parameter " << i + 1; + if (!parameter.name_.empty()) + os << " (" << std::quoted(parameter.name_) << ")"; + os << " of type"; + const auto& parameter_type = GetTypeAtIndex(parameter.typeId_); + auto diff = added ? Added(parameter_type, state) + : Removed(parameter_type, state); + result.AddDiff(os.str(), diff); + } return result; } // NOTE: not yet encountered in the wild -Result Variable::Equals(const Type &other, State &state) const { +Result +Variable::Equals(const Type& other, State& state) const +{ Result result; - const auto &o = other.as<Variable>(); + const auto& o = other.as<Variable>(); result.MaybeAddDiff("linkage", GetLinkage(), o.GetLinkage()); const auto var_diff = Compare(GetTypeAtIndex(GetVarTypeId()), - o.GetTypeAtIndex(o.GetVarTypeId()), state); + o.GetTypeAtIndex(o.GetVarTypeId()), + state); result.MaybeAddDiff("type", var_diff); return result; } -Result DataSection::Equals(const Type &other, State &state) const { +Result +DataSection::Equals(const Type& other, State& state) const +{ Result result; result.AddDiff("Unimplemented"); // NOTE: not yet encountered in the wild - m_assert(false, "Unimplemented\n"); // NOLINT + m_assert(false, "Unimplemented\n"); // NOLINT return result; } -Result ElfSymbol::Equals(const Type &other, State &state) const { +Result +ElfSymbol::Equals(const Type& other, State& state) const +{ Result result; - const auto &o = other.as<ElfSymbol>(); + const auto& o = other.as<ElfSymbol>(); // TODO: compare ELF symbol attributes - const auto type_diff = Compare(GetTypeAtIndex(type_id_), - o.GetTypeAtIndex(o.type_id_), state); + const auto type_diff = + Compare(GetTypeAtIndex(type_id_), o.GetTypeAtIndex(o.type_id_), state); result.MaybeAddDiff("type", type_diff); return result; } -const Type &Type::ResolveQualifiers(std::set<Kind> &qualifiers) const { - if (kind_ == BTF_KIND_ARRAY || kind_ == BTF_KIND_FUNC_PROTO) { - // There should be no qualifiers here. - qualifiers.clear(); - } +const Type& +Type::ResolveQualifiers(std::set<Kind>& qualifiers) const +{ + if (kind_ == BTF_KIND_ARRAY || kind_ == BTF_KIND_FUNC_PROTO) + { + // There should be no qualifiers here. + qualifiers.clear(); + } return *this; } -const Type &Qualifier::ResolveQualifiers( - std::set<Kind> &qualifiers) const { +const Type& +Qualifier::ResolveQualifiers(std::set<Kind>& qualifiers) const +{ qualifiers.insert(GetKind()); return GetTypeAtIndex(GetQualifiedTypeId()).ResolveQualifiers(qualifiers); } -const Type &Type::ResolveTypedef( - std::vector<std::string_view> &typedefs) const { +const Type& +Type::ResolveTypedef(std::vector<std::string_view>& typedefs) const +{ return *this; } -const Type &Typedef::ResolveTypedef( - std::vector<std::string_view> &typedefs) const { +const Type& +Typedef::ResolveTypedef(std::vector<std::string_view>& typedefs) const +{ typedefs.push_back(GetName()); return GetTypeAtIndex(GetReferredTypeId()).ResolveTypedef(typedefs); } -std::ostream &operator<<(std::ostream &os, const Type &bt) { +std::ostream& +operator<<(std::ostream& os, const Type& bt) +{ auto name = bt.GetName(); - os << kRawKindNames[bt.GetKind()] - << " '" << (name.empty() ? "(anon)" : name) << '\''; + os << kRawKindNames[bt.GetKind()] << " '" << (name.empty() ? "(anon)" : name) + << '\''; return os; } -std::ostream &operator<<(std::ostream &os, const Ptr &bp) { - os << static_cast<const Type &>(bp) - << " type_id=" << bp.GetPointeeTypeId() +std::ostream& +operator<<(std::ostream& os, const Ptr& bp) +{ + os << static_cast<const Type&>(bp) << " type_id=" << bp.GetPointeeTypeId() << '\n'; return os; } -std::ostream &operator<<(std::ostream &os, const Typedef &bp) { - os << static_cast<const Type &>(bp) - << " type_id=" << bp.GetReferredTypeId() +std::ostream& +operator<<(std::ostream& os, const Typedef& bp) +{ + os << static_cast<const Type&>(bp) << " type_id=" << bp.GetReferredTypeId() << '\n'; return os; } -std::ostream &operator<<(std::ostream &os, const Qualifier &bp) { - os << static_cast<const Type &>(bp) - << " type_id=" << bp.GetQualifiedTypeId() +std::ostream& +operator<<(std::ostream& os, const Qualifier& bp) +{ + os << static_cast<const Type&>(bp) << " type_id=" << bp.GetQualifiedTypeId() << '\n'; return os; } -std::ostream &operator<<(std::ostream &os, const Integer &bi) { - os << static_cast<const Type &>(bi) - << " size=" << bi.GetByteSize() - << " bits_offset=" << bi.GetOffset() - << " nr_bits=" << bi.GetBitSize() - << " bool=" << bi.isBool() - << " char=" << bi.isChar() - << " signed=" << bi.isSigned() - << '\n'; +std::ostream& +operator<<(std::ostream& os, const Integer& bi) +{ + os << static_cast<const Type&>(bi) << " size=" << bi.GetByteSize() + << " bits_offset=" << bi.GetOffset() << " nr_bits=" << bi.GetBitSize() + << " bool=" << bi.isBool() << " char=" << bi.isChar() + << " signed=" << bi.isSigned() << '\n'; return os; } -std::ostream &operator<<(std::ostream &os, const Array &ba) { - os << static_cast<const Type &>(ba) - << " type_id=" << ba.GetElementTypeId() - << " index_type_id=" << ba.GetIndexTypeId() - << " nr_elems=" << ba.GetNumberOfElements() - << '\n'; - return os; - } +std::ostream& +operator<<(std::ostream& os, const Array& ba) +{ + os << static_cast<const Type&>(ba) << " type_id=" << ba.GetElementTypeId() + << " index_type_id=" << ba.GetIndexTypeId() + << " nr_elems=" << ba.GetNumberOfElements() << '\n'; + return os; +} -std::ostream &operator<<(std::ostream &os, const StructUnion &bsu) { - os << static_cast<const Type &>(bsu) - << " size=" << bsu.GetByteSize() +std::ostream& +operator<<(std::ostream& os, const StructUnion& bsu) +{ + os << static_cast<const Type&>(bsu) << " size=" << bsu.GetByteSize() << " vlen=" << bsu.GetMembers().size() << '\n'; - for (const auto &member : bsu.GetMembers()) { - os << "\t'" << member.first << '\'' - << " type_id=" << member.second.typeId_ - << " bits_offset=" << member.second.offset_; - if (member.second.bitfieldSize_) - os << " bitfield_size=" << member.second.bitfieldSize_; - os << '\n'; - } + for (const auto& member : bsu.GetMembers()) + { + os << "\t'" << member.first << '\'' + << " type_id=" << member.second.typeId_ + << " bits_offset=" << member.second.offset_; + if (member.second.bitfieldSize_) + os << " bitfield_size=" << member.second.bitfieldSize_; + os << '\n'; + } return os; } -std::ostream &operator<<(std::ostream &os, const Enumeration &be) { - os << static_cast<const Type &>(be) - << " size=" << be.GetByteSize() - << " vlen=" << be.GetEnums().size() - << '\n'; - for (const auto &e : be.GetEnums()) { - os << "\t'" << e.first << "' val=" << e.second << '\n'; - } +std::ostream& +operator<<(std::ostream& os, const Enumeration& be) +{ + os << static_cast<const Type&>(be) << " size=" << be.GetByteSize() + << " vlen=" << be.GetEnums().size() << '\n'; + for (const auto& e : be.GetEnums()) + { + os << "\t'" << e.first << "' val=" << e.second << '\n'; + } return os; } -std::ostream &operator<<(std::ostream &os, const ForwardDeclaration &bfd) { - os << static_cast<const Type &>(bfd) - << " fwd_kind=" << bfd.GetFwdKind() +std::ostream& +operator<<(std::ostream& os, const ForwardDeclaration& bfd) +{ + os << static_cast<const Type&>(bfd) << " fwd_kind=" << bfd.GetFwdKind() << '\n'; return os; } -std::ostream &operator<<(std::ostream &os, const Function &bf) { - os << static_cast<const Type &>(bf) - << " type_id=" << bf.GetReferredTypeId() - << " linkage=" << bf.GetLinkage() - << '\n'; +std::ostream& +operator<<(std::ostream& os, const Function& bf) +{ + os << static_cast<const Type&>(bf) << " type_id=" << bf.GetReferredTypeId() + << " linkage=" << bf.GetLinkage() << '\n'; return os; } -std::ostream &operator<<(std::ostream &os, const FunctionPrototype &bfp) { - os << static_cast<const Type &>(bfp) +std::ostream& +operator<<(std::ostream& os, const FunctionPrototype& bfp) +{ + os << static_cast<const Type&>(bfp) << " ret_type_id=" << bfp.GetReturnTypeId() - << " vlen=" << bfp.GetParameters().size() - << '\n'; - for (const auto ¶m : bfp.GetParameters()) { - os << "\t'" << (param.name_.empty() ? "(anon)" : param.name_) - << "' type_id=" << param.typeId_ << '\n'; - } + << " vlen=" << bfp.GetParameters().size() << '\n'; + for (const auto& param : bfp.GetParameters()) + { + os << "\t'" << (param.name_.empty() ? "(anon)" : param.name_) + << "' type_id=" << param.typeId_ << '\n'; + } return os; } -std::ostream &operator<<(std::ostream &os, const Variable &bv) { +std::ostream& +operator<<(std::ostream& os, const Variable& bv) +{ // NOTE: The odd comma is to match bpftool dump. - os << static_cast<const Type &>(bv) - << " type_id=" << bv.GetVarTypeId() - << ", linkage=" << bv.GetLinkage() - << '\n'; + os << static_cast<const Type&>(bv) << " type_id=" << bv.GetVarTypeId() + << ", linkage=" << bv.GetLinkage() << '\n'; return os; } -std::ostream &operator<<(std::ostream &os, const DataSection &bds) { - os << static_cast<const Type &>(bds) - << " size=" << bds.GetByteSize() - << '\n'; - for (const auto &secinfo : bds.GetSecinfos()) { - os << "\ttype_id=" << secinfo.typeId_ - << " offset=" << secinfo.offset_ - << " size=" << secinfo.bytesize_ << '\n'; - } +std::ostream& +operator<<(std::ostream& os, const DataSection& bds) +{ + os << static_cast<const Type&>(bds) << " size=" << bds.GetByteSize() << '\n'; + for (const auto& secinfo : bds.GetSecinfos()) + { + os << "\ttype_id=" << secinfo.typeId_ << " offset=" << secinfo.offset_ + << " size=" << secinfo.bytesize_ << '\n'; + } return os; } -std::ostream &operator<<(std::ostream &os, const ElfSymbol &bes) { - os << static_cast<const Type &>(bes); +std::ostream& +operator<<(std::ostream& os, const ElfSymbol& bes) +{ + os << static_cast<const Type&>(bes); // TODO: report ELF symbol attributes - os << " type=" << bes.GetTypeId() - << '\n'; + os << " type=" << bes.GetTypeId() << '\n'; return os; } -std::ostream &operator<<(std::ostream &os, ForwardDeclarationKind kind) { - switch (kind) { +std::ostream& +operator<<(std::ostream& os, ForwardDeclarationKind kind) +{ + switch (kind) + { case ForwardDeclarationKind::STRUCT: os << "struct"; break; case ForwardDeclarationKind::UNION: os << "union"; break; - } + } return os; } -std::ostream &operator<<(std::ostream &os, Variable::Linkage linkage) { +std::ostream& +operator<<(std::ostream& os, Variable::Linkage linkage) +{ auto ix = static_cast<size_t>(linkage); return os << (ix < kVarLinkage.size() ? kVarLinkage[ix] : "(unknown)"); } -std::ostream &operator<<(std::ostream &os, Function::Linkage linkage) { +std::ostream& +operator<<(std::ostream& os, Function::Linkage linkage) +{ auto ix = static_cast<size_t>(linkage); return os << (ix < kFunLinkage.size() ? kFunLinkage[ix] : "(unknown)"); } -Structs::Structs(const char *start, - std::unique_ptr<abigail::ir::environment> env, - const abigail::symtab_reader::symtab_sptr tab, - const bool verbose) - : env_(std::move(env)), - tab_(tab), - verbose_(verbose) { - header_ = reinterpret_cast<const btf_header *>(start); +Structs::Structs(const char* start, + std::unique_ptr<abigail::ir::environment> env, + const abigail::symtab_reader::symtab_sptr tab, + const bool verbose) + : env_(std::move(env)), tab_(tab), verbose_(verbose) +{ + header_ = reinterpret_cast<const btf_header*>(start); m_assert(header_->magic == 0xEB9F, "Magic field must be 0xEB9F for BTF"); - type_section_ = reinterpret_cast<const btf_type *>(start + header_->hdr_len + - header_->type_off); + type_section_ = reinterpret_cast<const btf_type*>(start + header_->hdr_len + + header_->type_off); str_section_ = start + header_->hdr_len + header_->str_off; // every btf_type struct in the type section has an implicit type id. @@ -979,13 +1189,15 @@ Structs::Structs(const char *start, // recognized type starting from id 1. types_.push_back(std::make_unique<Void>(types_, 0, "void", 0)); - if (verbose_) { - PrintHeader(); - } + if (verbose_) + { + PrintHeader(); + } BuildTypes(); - if (verbose_) { - PrintStringSection(); - } + if (verbose_) + { + PrintStringSection(); + } // NOTE: a whole bunch of Linux kernel symbols appear with duplicate (but not // necessarily identical) BTF type information @@ -993,366 +1205,439 @@ Structs::Structs(const char *start, // TODO: find a better way of resolving this bad_prefix_1_ = "__arm64_sys_"; bad_prefix_2_ = "__arm64_compat_sys_"; - bad_names_ = { - "arch_prctl_spec_ctrl_get", - "arch_prctl_spec_ctrl_set", - "ioremap_cache", - "kvm_arch_set_irq_inatomic", - "module_frob_arch_sections", - "vsnprintf" - }; + bad_names_ = {"arch_prctl_spec_ctrl_get", + "arch_prctl_spec_ctrl_set", + "ioremap_cache", + "kvm_arch_set_irq_inatomic", + "module_frob_arch_sections", + "vsnprintf"}; } -void Structs::PrintHeader() { +void +Structs::PrintHeader() +{ std::cout << "BTF header:\n" - << "\tmagic " << header_->magic - << ", version " << static_cast<int>(header_->version) - << ", flags " << static_cast<int>(header_->flags) - << ", hdr_len " << header_->hdr_len << "\n" - << "\ttype_off " << header_->type_off - << ", type_len " << header_->type_len << "\n" - << "\tstr_off " << header_->str_off - << ", str_len " << header_->str_len << "\n"; + << "\tmagic " << header_->magic << ", version " + << static_cast<int>(header_->version) << ", flags " + << static_cast<int>(header_->flags) << ", hdr_len " + << header_->hdr_len << "\n" + << "\ttype_off " << header_->type_off << ", type_len " + << header_->type_len << "\n" + << "\tstr_off " << header_->str_off << ", str_len " + << header_->str_len << "\n"; } // vlen: vector length, the number of struct/union members -std::map<std::string, Member> Structs::BuildMembers( - bool kflag, const btf_member *members, size_t vlen) { +std::map<std::string, Member> +Structs::BuildMembers(bool kflag, const btf_member* members, size_t vlen) +{ std::map<std::string, Member> result; int anonymous = 0; - for (size_t i = 0; i < vlen; ++i) { - const auto raw_offset = members[i].offset; - Member member{ - .typeId_ = members[i].type, - .offset_ = kflag ? BTF_MEMBER_BIT_OFFSET(raw_offset) : raw_offset, - .bitfieldSize_ = kflag ? BTF_MEMBER_BITFIELD_SIZE(raw_offset) : 0}; - std::string name = std::string(GetName(members[i].name_off)); - if (name.empty()) { - name = "anon member #" + std::to_string(anonymous); - ++anonymous; + for (size_t i = 0; i < vlen; ++i) + { + const auto raw_offset = members[i].offset; + Member member{ + .typeId_ = members[i].type, + .offset_ = kflag ? BTF_MEMBER_BIT_OFFSET(raw_offset) : raw_offset, + .bitfieldSize_ = kflag ? BTF_MEMBER_BITFIELD_SIZE(raw_offset) : 0}; + std::string name = std::string(GetName(members[i].name_off)); + if (name.empty()) + { + name = "anon member #" + std::to_string(anonymous); + ++anonymous; + } + result.emplace(name, member); } - result.emplace(name, member); - } return result; } // vlen: vector length, the number of enum values -std::map<std::string, int> Structs::BuildEnums(const struct btf_enum *enums, - size_t vlen) { +std::map<std::string, int> +Structs::BuildEnums(const struct btf_enum* enums, size_t vlen) +{ std::map<std::string, int> result; - for (size_t i = 0; i < vlen; ++i) { - result.emplace(std::string(GetName(enums[i].name_off)), enums[i].val); - } + for (size_t i = 0; i < vlen; ++i) + { + result.emplace(std::string(GetName(enums[i].name_off)), enums[i].val); + } return result; } // vlen: vector length, the number of parameters -std::vector<Parameter> Structs::BuildParams(const struct btf_param *params, - size_t vlen) { +std::vector<Parameter> +Structs::BuildParams(const struct btf_param* params, size_t vlen) +{ std::vector<Parameter> result; result.reserve(vlen); - for (size_t i = 0; i < vlen; ++i) { - Parameter parameter{ - .name_ = std::string(GetName(params[i].name_off)), - .typeId_ = params[i].type}; - result.push_back(parameter); - } + for (size_t i = 0; i < vlen; ++i) + { + Parameter parameter{.name_ = std::string(GetName(params[i].name_off)), + .typeId_ = params[i].type}; + result.push_back(parameter); + } return result; } // vlen: vector length, the number of variables -std::vector<Secinfo> Structs::BuildDatasec(const btf_type *type, - size_t vlen) { +std::vector<Secinfo> +Structs::BuildDatasec(const btf_type* type, size_t vlen) +{ std::vector<Secinfo> result; result.reserve(vlen); - const auto *secinfos = reinterpret_cast<const btf_var_secinfo *>(type + 1); - for (size_t i = 0; i < vlen; ++i) { - Secinfo secinfo{.typeId_ = secinfos[i].type, - .offset_ = secinfos[i].offset, - .bytesize_ = secinfos[i].size}; - result.push_back(secinfo); - } + const auto* secinfos = reinterpret_cast<const btf_var_secinfo*>(type + 1); + for (size_t i = 0; i < vlen; ++i) + { + Secinfo secinfo{.typeId_ = secinfos[i].type, + .offset_ = secinfos[i].offset, + .bytesize_ = secinfos[i].size}; + result.push_back(secinfo); + } return result; } -void Structs::BuildTypes() { - m_assert(!(header_->type_off & (sizeof(uint32_t) - 1)), "Unaligned type_off"); - if (header_->type_len == 0) { - std::cerr << "No types found"; - return; - } - if (verbose_) { - std::cout << "Type section:\n"; - } +void +Structs::BuildTypes() +{ + m_assert(!(header_->type_off & (sizeof(uint32_t) - 1)), + "Unaligned type_off"); + if (header_->type_len == 0) + { + std::cerr << "No types found"; + return; + } + if (verbose_) + { + std::cout << "Type section:\n"; + } - const char *curr = reinterpret_cast<const char *>(type_section_); - const char *end = curr + header_->type_len; + const char* curr = reinterpret_cast<const char*>(type_section_); + const char* end = curr + header_->type_len; uint32_t index = 1; - while (curr < end) { - const btf_type *t = reinterpret_cast<const btf_type *>(curr); - int type_size = BuildOneType(t, index); - m_assert(type_size > 0, "Could not identify BTF type"); - curr += type_size; - ++index; - } + while (curr < end) + { + const btf_type* t = reinterpret_cast<const btf_type*>(curr); + int type_size = BuildOneType(t, index); + m_assert(type_size > 0, "Could not identify BTF type"); + curr += type_size; + ++index; + } BuildElfSymbols(); } -int Structs::BuildOneType(const btf_type *t, uint32_t index) { +int +Structs::BuildOneType(const btf_type* t, uint32_t index) +{ const auto kind = BTF_INFO_KIND(t->info); const auto vlen = BTF_INFO_VLEN(t->info); // Data following the btf_type struct. - const void *data = reinterpret_cast<const void *>(t + 1); + const void* data = reinterpret_cast<const void*>(t + 1); m_assert(kind >= 0 && kind < NR_BTF_KINDS, "Unknown BTF kind"); - if (verbose_) std::cout << '[' << index << "] "; + if (verbose_) + std::cout << '[' << index << "] "; int type_size = sizeof(struct btf_type); - switch (kind) { - case BTF_KIND_INT: { - const auto bits = *reinterpret_cast<const uint32_t *>(data); - types_.push_back(std::make_unique<Integer>( - types_, index, GetName(t->name_off), kind, - BTF_INT_ENCODING(bits), BTF_INT_OFFSET(bits), BTF_INT_BITS(bits), - t->size)); - if (verbose_) { - std::cout << types_.back()->as<Integer>(); + switch (kind) + { + case BTF_KIND_INT: + { + const auto bits = *reinterpret_cast<const uint32_t*>(data); + types_.push_back(std::make_unique<Integer>(types_, + index, + GetName(t->name_off), + kind, + BTF_INT_ENCODING(bits), + BTF_INT_OFFSET(bits), + BTF_INT_BITS(bits), + t->size)); + if (verbose_) + { + std::cout << types_.back()->as<Integer>(); + } + type_size += sizeof(uint32_t); + break; } - type_size += sizeof(uint32_t); - break; - } - case BTF_KIND_PTR: { - types_.push_back(std::make_unique<Ptr>( - types_, index, GetName(t->name_off), kind, t->type)); - if (verbose_) { - std::cout << types_.back()->as<Ptr>(); + case BTF_KIND_PTR: + { + types_.push_back(std::make_unique<Ptr>( + types_, index, GetName(t->name_off), kind, t->type)); + if (verbose_) + { + std::cout << types_.back()->as<Ptr>(); + } + break; } - break; - } - case BTF_KIND_TYPEDEF: { - types_.push_back(std::make_unique<Typedef>( - types_, index, GetName(t->name_off), kind, t->type)); - if (verbose_) { - std::cout << types_.back()->as<Typedef>(); + case BTF_KIND_TYPEDEF: + { + types_.push_back(std::make_unique<Typedef>( + types_, index, GetName(t->name_off), kind, t->type)); + if (verbose_) + { + std::cout << types_.back()->as<Typedef>(); + } + break; } - break; - } case BTF_KIND_VOLATILE: case BTF_KIND_CONST: - case BTF_KIND_RESTRICT: { - types_.push_back(std::make_unique<Qualifier>( - types_, index, GetName(t->name_off), kind, t->type)); - if (verbose_) { - std::cout << types_.back()->as<Qualifier>(); + case BTF_KIND_RESTRICT: + { + types_.push_back(std::make_unique<Qualifier>( + types_, index, GetName(t->name_off), kind, t->type)); + if (verbose_) + { + std::cout << types_.back()->as<Qualifier>(); + } + break; } - break; - } - case BTF_KIND_ARRAY: { - const auto *array = reinterpret_cast<const struct btf_array *>(data); - types_.push_back(std::make_unique<Array>( - types_, index, GetName(t->name_off), kind, array->type, - array->index_type, array->nelems)); - if (verbose_) { - std::cout << types_.back()->as<Array>(); + case BTF_KIND_ARRAY: + { + const auto* array = reinterpret_cast<const struct btf_array*>(data); + types_.push_back(std::make_unique<Array>(types_, + index, + GetName(t->name_off), + kind, + array->type, + array->index_type, + array->nelems)); + if (verbose_) + { + std::cout << types_.back()->as<Array>(); + } + type_size += sizeof(struct btf_array); + break; } - type_size += sizeof(struct btf_array); - break; - } case BTF_KIND_STRUCT: - case BTF_KIND_UNION: { - const bool kflag = BTF_INFO_KFLAG(t->info); - const auto *btf_members = reinterpret_cast<const btf_member *>(data); - const auto members = BuildMembers(kflag, btf_members, vlen); - types_.push_back(std::make_unique<StructUnion>( - types_, index, GetName(t->name_off), kind, t->size, members)); - if (verbose_) { - std::cout << types_.back()->as<StructUnion>(); - } - type_size += vlen * sizeof(struct btf_member); - break; - } - case BTF_KIND_ENUM: { - const auto *enums = reinterpret_cast<const struct btf_enum *>(data); - std::map<std::string, int> enumerators = BuildEnums(enums, vlen); - types_.push_back(std::make_unique<Enumeration>( - types_, index, GetName(t->name_off), kind, - t->size, enumerators)); - if (verbose_) { - std::cout << types_.back()->as<Enumeration>(); + case BTF_KIND_UNION: + { + const bool kflag = BTF_INFO_KFLAG(t->info); + const auto* btf_members = reinterpret_cast<const btf_member*>(data); + const auto members = BuildMembers(kflag, btf_members, vlen); + types_.push_back(std::make_unique<StructUnion>( + types_, index, GetName(t->name_off), kind, t->size, members)); + if (verbose_) + { + std::cout << types_.back()->as<StructUnion>(); + } + type_size += vlen * sizeof(struct btf_member); + break; } - type_size += vlen * sizeof(struct btf_enum); - break; - } - case BTF_KIND_FWD: { - const bool kflag = BTF_INFO_KFLAG(t->info); - types_.push_back(std::make_unique<ForwardDeclaration>( - types_, index, GetName(t->name_off), kind, kflag)); - if (verbose_) { - std::cout << types_.back()->as<ForwardDeclaration>(); + case BTF_KIND_ENUM: + { + const auto* enums = reinterpret_cast<const struct btf_enum*>(data); + std::map<std::string, int> enumerators = BuildEnums(enums, vlen); + types_.push_back(std::make_unique<Enumeration>( + types_, index, GetName(t->name_off), kind, t->size, enumerators)); + if (verbose_) + { + std::cout << types_.back()->as<Enumeration>(); + } + type_size += vlen * sizeof(struct btf_enum); + break; } - break; - } - case BTF_KIND_FUNC: { - const auto name = GetName(t->name_off); - types_.push_back(std::make_unique<Function>( - types_, index, name, kind, t->type, - Function::Linkage(vlen))); - if (verbose_) { - std::cout << types_.back()->as<Function>(); + case BTF_KIND_FWD: + { + const bool kflag = BTF_INFO_KFLAG(t->info); + types_.push_back(std::make_unique<ForwardDeclaration>( + types_, index, GetName(t->name_off), kind, kflag)); + if (verbose_) + { + std::cout << types_.back()->as<ForwardDeclaration>(); + } + break; } - bool inserted = btf_symbol_types_.insert({name, t->type}).second; - if (!inserted) { - // NOTE: duplicate BTF symbols could be considered a bug in pahole - // - // TODO: remove these checks once resolved - bool known = !name.compare(0, bad_prefix_1_.size(), bad_prefix_1_) || - !name.compare(0, bad_prefix_2_.size(), bad_prefix_2_) || - std::find(bad_names_.begin(), bad_names_.end(), name) != - bad_names_.end(); - m_assert(known, "Insertion failed, duplicate found in symbol map"); - (void)known; + case BTF_KIND_FUNC: + { + const auto name = GetName(t->name_off); + types_.push_back(std::make_unique<Function>( + types_, index, name, kind, t->type, Function::Linkage(vlen))); + if (verbose_) + { + std::cout << types_.back()->as<Function>(); + } + bool inserted = btf_symbol_types_.insert({name, t->type}).second; + if (!inserted) + { + // NOTE: duplicate BTF symbols could be considered a bug in pahole + // + // TODO: remove these checks once resolved + bool known = + !name.compare(0, bad_prefix_1_.size(), bad_prefix_1_) + || !name.compare(0, bad_prefix_2_.size(), bad_prefix_2_) + || std::find(bad_names_.begin(), bad_names_.end(), name) + != bad_names_.end(); + m_assert(known, "Insertion failed, duplicate found in symbol map"); + (void) known; + } + btf_symbols_.insert({name, types_.back().get()}); + break; } - btf_symbols_.insert({name, types_.back().get()}); - break; - } - case BTF_KIND_FUNC_PROTO: { - const auto *params = reinterpret_cast<const btf_param *>(data); - std::vector<Parameter> parameters = BuildParams(params, vlen); - types_.push_back(std::make_unique<FunctionPrototype>( - types_, index, GetName(t->name_off), kind, t->type, - parameters)); - if (verbose_) { - std::cout << types_.back()->as<FunctionPrototype>(); + case BTF_KIND_FUNC_PROTO: + { + const auto* params = reinterpret_cast<const btf_param*>(data); + std::vector<Parameter> parameters = BuildParams(params, vlen); + types_.push_back(std::make_unique<FunctionPrototype>( + types_, index, GetName(t->name_off), kind, t->type, parameters)); + if (verbose_) + { + std::cout << types_.back()->as<FunctionPrototype>(); + } + type_size += vlen * sizeof(struct btf_param); + break; } - type_size += vlen * sizeof(struct btf_param); - break; - } - case BTF_KIND_VAR: { - // NOTE: not yet encountered in the wild - const auto *variable = reinterpret_cast<const struct btf_var *>(data); - const auto name = GetName(t->name_off); - types_.push_back(std::make_unique<Variable>( - types_, index, name, kind, t->type, - Variable::Linkage(variable->linkage))); - if (verbose_) { - std::cout << types_.back()->as<Variable>(); + case BTF_KIND_VAR: + { + // NOTE: not yet encountered in the wild + const auto* variable = reinterpret_cast<const struct btf_var*>(data); + const auto name = GetName(t->name_off); + types_.push_back( + std::make_unique<Variable>(types_, + index, + name, + kind, + t->type, + Variable::Linkage(variable->linkage))); + if (verbose_) + { + std::cout << types_.back()->as<Variable>(); + } + + bool inserted = btf_symbol_types_.insert({name, t->type}).second; + m_assert(inserted, "Insertion failed, duplicate found in symbol map"); + (void) inserted; + btf_symbols_.insert({name, types_.back().get()}); + + type_size += sizeof(struct btf_var); + break; } - - bool inserted = btf_symbol_types_.insert({name, t->type}).second; - m_assert(inserted, "Insertion failed, duplicate found in symbol map"); - (void)inserted; - btf_symbols_.insert({name, types_.back().get()}); - - type_size += sizeof(struct btf_var); - break; - } - case BTF_KIND_DATASEC: { - std::vector<Secinfo> secinfos = BuildDatasec(t, vlen); - types_.push_back(std::make_unique<DataSection>( - types_, index, GetName(t->name_off), kind, t->size, - secinfos)); - if (verbose_) { - std::cout << types_.back()->as<DataSection>(); + case BTF_KIND_DATASEC: + { + std::vector<Secinfo> secinfos = BuildDatasec(t, vlen); + types_.push_back(std::make_unique<DataSection>( + types_, index, GetName(t->name_off), kind, t->size, secinfos)); + if (verbose_) + { + std::cout << types_.back()->as<DataSection>(); + } + type_size += vlen * sizeof(struct btf_var_secinfo); } - type_size += vlen * sizeof(struct btf_var_secinfo); } - } return type_size; } -std::string_view Structs::GetName(uint32_t name_off) { +std::string_view +Structs::GetName(uint32_t name_off) +{ m_assert(name_off < header_->str_len, - "The name offset exceeds the section length"); - const char *section_end = str_section_ + header_->str_len; - const char *name_end = std::find(&str_section_[name_off], section_end, '\0'); + "The name offset exceeds the section length"); + const char* section_end = str_section_ + header_->str_len; + const char* name_end = std::find(&str_section_[name_off], section_end, '\0'); m_assert(name_end < section_end, - "The name continues past the string section limit"); - (void)name_end; + "The name continues past the string section limit"); + (void) name_end; std::string_view name{&str_section_[name_off]}; return name; } -void Structs::PrintStringSection() { +void +Structs::PrintStringSection() +{ std::cout << "String section:\n"; - const char *curr = str_section_; - const char *limit = str_section_ + header_->str_len; - while (curr < limit) { - const char *pos = std::find(curr, limit, '\0'); - m_assert(pos < limit, "Error reading the string section"); - std::cout << ' ' << curr; - curr = pos + 1; - } + const char* curr = str_section_; + const char* limit = str_section_ + header_->str_len; + while (curr < limit) + { + const char* pos = std::find(curr, limit, '\0'); + m_assert(pos < limit, "Error reading the string section"); + std::cout << ' ' << curr; + curr = pos + 1; + } std::cout << '\n'; } -void Structs::BuildElfSymbols() { +void +Structs::BuildElfSymbols() +{ const auto filter = [&]() { auto filter = tab_->make_filter(); filter.set_public_symbols(); return filter; }(); - for (const auto &symbol : - abigail::symtab_reader::filtered_symtab(*tab_, filter)) { - const auto &symbol_name = symbol->get_name(); - const auto &main_symbol_name = symbol->get_main_symbol()->get_name(); - auto it = btf_symbol_types_.find(main_symbol_name); - if (it == btf_symbol_types_.end()) { - // missing BTF information is tracked explicitly - std::cerr << "ELF symbol " << std::quoted(symbol_name); - if (symbol_name != main_symbol_name) - std::cerr << " (aliased to " << std::quoted(main_symbol_name) << ')'; - std::cerr << " BTF info missing\n"; - types_.push_back(nullptr); - } else { - uint32_t type_id = it->second; - types_.push_back(std::make_unique<ElfSymbol>(types_, symbol, type_id)); + for (const auto& symbol : + abigail::symtab_reader::filtered_symtab(*tab_, filter)) + { + const auto& symbol_name = symbol->get_name(); + const auto& main_symbol_name = symbol->get_main_symbol()->get_name(); + auto it = btf_symbol_types_.find(main_symbol_name); + if (it == btf_symbol_types_.end()) + { + // missing BTF information is tracked explicitly + std::cerr << "ELF symbol " << std::quoted(symbol_name); + if (symbol_name != main_symbol_name) + std::cerr << " (aliased to " << std::quoted(main_symbol_name) + << ')'; + std::cerr << " BTF info missing\n"; + types_.push_back(nullptr); + } + else + { + uint32_t type_id = it->second; + types_.push_back( + std::make_unique<ElfSymbol>(types_, symbol, type_id)); + } + elf_symbols_.emplace(symbol_name, types_.back().get()); } - elf_symbols_.emplace(symbol_name, types_.back().get()); - } } -class ElfHandle { - public: - ElfHandle(const std::string &path) : dwfl_(nullptr, dwfl_end) { +class ElfHandle +{ +public: + ElfHandle(const std::string& path) : dwfl_(nullptr, dwfl_end) + { string name; tools_utils::base_name(path, name); elf_version(EV_CURRENT); dwfl_ = std::unique_ptr<Dwfl, decltype(&dwfl_end)>( - dwfl_begin(&offline_callbacks_), dwfl_end); - auto dwfl_module = dwfl_report_offline(dwfl_.get(), name.c_str(), - path.c_str(), -1); + dwfl_begin(&offline_callbacks_), dwfl_end); + auto dwfl_module = + dwfl_report_offline(dwfl_.get(), name.c_str(), path.c_str(), -1); GElf_Addr bias; elf_handle_ = dwfl_module_getelf(dwfl_module, &bias); } // Conversion operator to act as a drop-in replacement for Elf* - operator Elf *() const { return elf_handle_; } + operator Elf*() const { return elf_handle_; } - Elf *get() const { return elf_handle_; } + Elf* + get() const + { + return elf_handle_; + } - private: +private: // Dwfl owns all our data, hence only keep track of this std::unique_ptr<Dwfl, decltype(&dwfl_end)> dwfl_; - Elf *elf_handle_; + Elf* elf_handle_; Dwfl_Callbacks offline_callbacks_; }; -Structs ReadFile(const std::string &path, bool verbose) { +Structs +ReadFile(const std::string& path, bool verbose) +{ using abigail::symtab_reader::symtab; ElfHandle elf(path); m_assert(elf.get() != nullptr, "Could not get elf handle from file."); - Elf_Scn *btf_section = + Elf_Scn* btf_section = abigail::elf_helpers::find_section(elf, ".BTF", SHT_PROGBITS); m_assert(btf_section != nullptr, - "The given file does not have a BTF section"); - Elf_Data *elf_data = elf_rawdata(btf_section, 0); + "The given file does not have a BTF section"); + Elf_Data* elf_data = elf_rawdata(btf_section, 0); m_assert(elf_data != nullptr, "The BTF section is invalid"); - const char *btf_start = static_cast<char *>(elf_data->d_buf); + const char* btf_start = static_cast<char*>(elf_data->d_buf); auto env = std::make_unique<abigail::ir::environment>(); auto tab = symtab::load(elf, env.get()); @@ -1360,5 +1645,5 @@ Structs ReadFile(const std::string &path, bool verbose) { return Structs(btf_start, std::move(env), std::move(tab), verbose); } -} // end namespace btf -} // end namespace abigail +} // end namespace btf +} // end namespace abigail diff --git a/tests/test-scc.cc b/tests/test-scc.cc index ccabb471..c0c685c0 100644 --- a/tests/test-scc.cc +++ b/tests/test-scc.cc @@ -19,83 +19,109 @@ #include "abg-scc.h" -namespace Test { +namespace Test +{ using abigail::SCC; // Nodes are [0, N), the sets are the out-edges. typedef std::vector<std::set<size_t>> Graph; -std::ostream &operator<<(std::ostream &os, const Graph &g) { - for (size_t i = 0; i < g.size(); ++i) { - os << i << ':'; - for (auto o : g[i]) - os << ' ' << o; - os << '\n'; - } +std::ostream& +operator<<(std::ostream& os, const Graph& g) +{ + for (size_t i = 0; i < g.size(); ++i) + { + os << i << ':'; + for (auto o : g[i]) + os << ' ' << o; + os << '\n'; + } return os; } -template<typename G> Graph invent(size_t n, G& gen) { +template <typename G> +Graph +invent(size_t n, G& gen) +{ Graph graph(n); std::uniform_int_distribution<int> toss(0, 1); - for (auto &node : graph) { - for (size_t o = 0; o < n; ++o) { - if (toss(gen)) - node.insert(o); + for (auto& node : graph) + { + for (size_t o = 0; o < n; ++o) + { + if (toss(gen)) + node.insert(o); + } } - } return graph; } // Generate a graph g' where a -> b iff a and b are strongly connected in g. -Graph symmetric_subset_of_reflexive_transitive_closure(Graph g) { +Graph +symmetric_subset_of_reflexive_transitive_closure(Graph g) +{ const size_t n = g.size(); // transitive closure using Floyd-Warshall for (size_t o = 0; o < n; ++o) g[o].insert(o); - for (size_t k = 0; k < n; ++k) { - for (size_t i = 0; i < n; ++i) { - for (size_t j = 0; j < n; ++j) { - if (!g[i].count(j) && g[i].count(k) && g[k].count(j)) - g[i].insert(j); - } + for (size_t k = 0; k < n; ++k) + { + for (size_t i = 0; i < n; ++i) + { + for (size_t j = 0; j < n; ++j) + { + if (!g[i].count(j) && g[i].count(k) && g[k].count(j)) + g[i].insert(j); + } + } } - } // now a -> b iff a has path to b in g - for (size_t i = 0; i < n; ++i) { - for (size_t j = i + 1; j < n; ++j) { - // discard a -> b if not b -> a and vice versa - auto ij = g[i].count(j); - auto ji = g[j].count(i); - if (ij < ji) g[j].erase(i); - if (ji < ij) g[i].erase(j); + for (size_t i = 0; i < n; ++i) + { + for (size_t j = i + 1; j < n; ++j) + { + // discard a -> b if not b -> a and vice versa + auto ij = g[i].count(j); + auto ji = g[j].count(i); + if (ij < ji) + g[j].erase(i); + if (ji < ij) + g[i].erase(j); + } } - } // now have a -> b iff a has path to b and b has path to a in g return g; } // Generate a graph where a -> b iff a and b are in the same SCC. -Graph scc_strong_connectivity(const std::vector<std::set<size_t>> &sccs) { +Graph +scc_strong_connectivity(const std::vector<std::set<size_t>>& sccs) +{ size_t n = 0; - std::map<size_t, const std::set<size_t> *> edges; - for (const auto &scc : sccs) { - for (auto o : scc) { - if (o >= n) - n = o + 1; - edges[o] = &scc; + std::map<size_t, const std::set<size_t>*> edges; + for (const auto& scc : sccs) + { + for (auto o : scc) + { + if (o >= n) + n = o + 1; + edges[o] = &scc; + } } - } Graph g(n); for (size_t o = 0; o < n; ++o) g[o] = *edges[o]; return g; } -void dfs(std::set<size_t> &visited, SCC<size_t> &scc, - const Graph &g, size_t node, - std::vector<std::set<size_t>> &sccs) { +void +dfs(std::set<size_t>& visited, + SCC<size_t>& scc, + const Graph& g, + size_t node, + std::vector<std::set<size_t>>& sccs) +{ if (visited.count(node)) return; auto handle = scc.Open(node); @@ -104,17 +130,21 @@ void dfs(std::set<size_t> &visited, SCC<size_t> &scc, for (auto o : g[node]) dfs(visited, scc, g, o, sccs); auto nodes = scc.Close(handle.value()); - if (!nodes.empty()) { - std::set<size_t> scc_set; - for (auto o : nodes) { - CHECK(visited.insert(o).second); - CHECK(scc_set.insert(o).second); + if (!nodes.empty()) + { + std::set<size_t> scc_set; + for (auto o : nodes) + { + CHECK(visited.insert(o).second); + CHECK(scc_set.insert(o).second); + } + sccs.push_back(scc_set); } - sccs.push_back(scc_set); - } } -void process(const Graph &g) { +void +process(const Graph& g) +{ const size_t n = g.size(); // find SCCs @@ -126,21 +156,25 @@ void process(const Graph &g) { // check partition and topological order properties std::set<size_t> seen; - for (const auto &nodes : sccs) { - CHECK(!nodes.empty()); - for (auto node : nodes) { - // value in range [0, n) - CHECK(node < n); - // value seen at most once - CHECK(seen.insert(node).second); - } - for (auto node : nodes) { - for (auto o : g[node]) { - // edges point to nodes in this or earlier SCCs - CHECK(seen.count(o)); - } + for (const auto& nodes : sccs) + { + CHECK(!nodes.empty()); + for (auto node : nodes) + { + // value in range [0, n) + CHECK(node < n); + // value seen at most once + CHECK(seen.insert(node).second); + } + for (auto node : nodes) + { + for (auto o : g[node]) + { + // edges point to nodes in this or earlier SCCs + CHECK(seen.count(o)); + } + } } - } // exactly n values seen CHECK(seen.size() == n); @@ -148,15 +182,18 @@ void process(const Graph &g) { auto g_scc_closure = scc_strong_connectivity(sccs); auto g_closure = symmetric_subset_of_reflexive_transitive_closure(g); // catch isn't printing nicely - if (g_scc_closure != g_closure) { - std::cerr << "original:\n" << g - << "SCC finder:\n" << g_scc_closure - << "SCCs independently:\n" << g_closure; - } + if (g_scc_closure != g_closure) + { + std::cerr << "original:\n" + << g << "SCC finder:\n" + << g_scc_closure << "SCCs independently:\n" + << g_closure; + } CHECK(g_scc_closure == g_closure); } -TEST_CASE("randomly-generated graphs") { +TEST_CASE("randomly-generated graphs") +{ std::mt19937 gen; auto seed = gen(); // NOTES: @@ -164,20 +201,20 @@ TEST_CASE("randomly-generated graphs") { // There are O(2^k^2) possible directed graphs of size k. // Testing costs are O(k^3) so we restrict accordingly. uint64_t budget = 10000; - for (size_t k = 0; k < 7; ++k) { - uint64_t count = std::min(static_cast<uint64_t>(1) << (k*k), - budget / (k ? k * k * k : 1)); - INFO("testing with " << count << " graphs of size " << k); - for (uint64_t n = 0; n < count; ++n, ++seed) { - gen.seed(seed); - Graph g = invent(k, gen); - std::ostringstream os; - os << "a graph of " << k << " nodes generated using seed " << seed; - GIVEN(os.str()) { - process(g); - } + for (size_t k = 0; k < 7; ++k) + { + uint64_t count = std::min(static_cast<uint64_t>(1) << (k * k), + budget / (k ? k * k * k : 1)); + INFO("testing with " << count << " graphs of size " << k); + for (uint64_t n = 0; n < count; ++n, ++seed) + { + gen.seed(seed); + Graph g = invent(k, gen); + std::ostringstream os; + os << "a graph of " << k << " nodes generated using seed " << seed; + GIVEN(os.str()) { process(g); } + } } - } } -} // namespace Test +} // namespace Test diff --git a/tools/btfdiff.cc b/tools/btfdiff.cc index 58c40e42..e7fc27c8 100644 --- a/tools/btfdiff.cc +++ b/tools/btfdiff.cc @@ -16,7 +16,9 @@ const int kAbiChange = 4; -int main(int argc, char* argv[]) { +int +main(int argc, char* argv[]) +{ bool use_elf_symbols = true; static option opts[]{ {"symbols", required_argument, nullptr, 's'}, @@ -32,24 +34,26 @@ int main(int argc, char* argv[]) { << "' unrecognized argument '" << optarg << "'\n"; return usage(); }; - while (true) { - int ix; - int c = getopt_long(argc, argv, "s:", opts, &ix); - if (c == -1) - break; - switch (c) { - case 's': - if (!strcmp(optarg, "btf")) - use_elf_symbols = false; - else if (!strcmp(optarg, "elf")) - use_elf_symbols = true; - else - return bad_arg(ix); - break; - default: - return usage(); + while (true) + { + int ix; + int c = getopt_long(argc, argv, "s:", opts, &ix); + if (c == -1) + break; + switch (c) + { + case 's': + if (!strcmp(optarg, "btf")) + use_elf_symbols = false; + else if (!strcmp(optarg, "elf")) + use_elf_symbols = true; + else + return bad_arg(ix); + break; + default: + return usage(); + } } - } if (optind + 2 != argc) return usage(); diff --git a/tools/btfinfo.cc b/tools/btfinfo.cc index dbda7945..8b40cc96 100644 --- a/tools/btfinfo.cc +++ b/tools/btfinfo.cc @@ -7,11 +7,14 @@ #include "abg-btf.h" -int main(int argc, const char *argv[]) { - if (argc != 2) { - std::cerr << "Please specify the path to a BTF file."; - return 1; - } +int +main(int argc, const char* argv[]) +{ + if (argc != 2) + { + std::cerr << "Please specify the path to a BTF file."; + return 1; + } (void) abigail::btf::ReadFile(argv[1], /* verbose = */ true); -- 2.32.0.272.g935e593368-goog ^ permalink raw reply [flat|nested] 14+ messages in thread
* [PATCH v2 0/6] BTF ABI 2021-06-11 15:33 [PATCH 0/6] BTF ABI Giuliano Procida ` (5 preceding siblings ...) 2021-06-11 15:33 ` [PATCH 6/6] BTF: clang-format all the new source files Giuliano Procida @ 2021-06-22 10:33 ` Giuliano Procida 2021-06-22 10:33 ` [PATCH v2 1/6] Allow C++17 code to be compiled Giuliano Procida ` (5 more replies) 6 siblings, 6 replies; 14+ messages in thread From: Giuliano Procida @ 2021-06-22 10:33 UTC (permalink / raw) To: libabigail; +Cc: dodji, kernel-team, gprocida, maennich Hi. This code was developed by Maria Teguiani who interned with Android last summer and later by me. BTF is the BPF type format. See: https://www.kernel.org/doc/html/latest/bpf/btf.html The Linux kernel can be compiled with BTF type information. Together with the kernel and ELF symtabs, it can be used to as an alternative basis for kernel ABI monitoring. BTF has several limitations compared with libabigail ABI XML. Foremost, it supports C types only. There are also some other significant issues that may be resolved with time. The simplicity of BTF makes it an ideal vehicle for experimentation. An ELF object file containing DWARF debug information can be augmented with BTF debug information using pahole -J. pahole is part of dwarves. These patches contribute: - a BTF parser / BTF graph builder - code to dump BTF information as it is parsed - a BTF graph difference algorithm to generate graphs of differences - a C type name generator - code to serialise a difference graph as a text report The graph difference algorithm uses a strongly-connected component finder based on the path-based SCC algorithm. My main contribution here was the design which allows the BTF graph difference algorithm to be written in a straightforward recursive style. New in v2: - Fixed bug around ELF symbol lifetimes and the use of string_view. - Performances tweaks making more pieces of the diff algorithm O(N). Missing from these patches are: - Some documentation I wrote in markdown format. - A suite of small tests, of which the C language ones have been used to validate the BTF utilities. I hope this work will be useful to anyone wishing to experiment with BTF as an ABI representation or who has an interest in graph diff algorithms. Feedback is very welcome. Regards, Giuliano. Giuliano Procida (6): Allow C++17 code to be compiled Tweak clang-format BTF: add SCC finder and test BTF: add core functionality BTF: add btfinfo and btfdiff tools BTF: clang-format all the new source files .clang-format | 9 +- COMPILING | 5 + configure.ac | 21 +- include/abg-btf.h | 946 ++++++++++++++++++++++++++ include/abg-scc.h | 121 ++++ src/Makefile.am | 9 +- src/abg-btf.cc | 1650 +++++++++++++++++++++++++++++++++++++++++++++ tests/Makefile.am | 7 + tests/test-scc.cc | 220 ++++++ tools/Makefile.am | 14 + tools/btfdiff.cc | 71 ++ tools/btfinfo.cc | 22 + 12 files changed, 3092 insertions(+), 3 deletions(-) create mode 100644 include/abg-btf.h create mode 100644 include/abg-scc.h create mode 100644 src/abg-btf.cc create mode 100644 tests/test-scc.cc create mode 100644 tools/btfdiff.cc create mode 100644 tools/btfinfo.cc -- 2.32.0.288.g62a8d224e6-goog ^ permalink raw reply [flat|nested] 14+ messages in thread
* [PATCH v2 1/6] Allow C++17 code to be compiled 2021-06-22 10:33 ` [PATCH v2 0/6] BTF ABI Giuliano Procida @ 2021-06-22 10:33 ` Giuliano Procida 2021-06-22 10:33 ` [PATCH v2 2/6] Tweak clang-format Giuliano Procida ` (4 subsequent siblings) 5 siblings, 0 replies; 14+ messages in thread From: Giuliano Procida @ 2021-06-22 10:33 UTC (permalink / raw) To: libabigail; +Cc: dodji, kernel-team, gprocida, maennich The BTF code and abitidy tool were both developed in a C++17 environment. Allow C++17 to be enabled at configuration time. * configure.ac: Add --enable-cxx17 option, defaulting to no. Signed-off-by: Giuliano Procida <gprocida@google.com> --- configure.ac | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/configure.ac b/configure.ac index 735cc9de..edd03cf8 100644 --- a/configure.ac +++ b/configure.ac @@ -138,6 +138,12 @@ AC_ARG_ENABLE(ubsan, ENABLE_UBSAN=$enableval, ENABLE_UBSAN=no) +AC_ARG_ENABLE(cxx17, + AS_HELP_STRING([--enable-cxx17=yes|no], + [enable features that use the C++17 compiler]), + ENABLE_CXX17=$enableval, + ENABLE_CXX17=no) + dnl ************************************************* dnl check for dependencies dnl ************************************************* @@ -153,7 +159,7 @@ AC_LANG([C++]) AC_LANG_COMPILER_REQUIRE dnl -dnl We use C++11 +dnl We use C++11 or C++17 if enabled dnl CXX_STANDARD=c++11 @@ -591,6 +597,12 @@ AX_VALGRIND_DFLT(sgcheck, off) AX_VALGRIND_CHECK +dnl Handle conditional use of a C++17 compiler +if test x$ENABLE_CXX17 = xyes; then + CXX_STANDARD=c++17 +fi +AM_CONDITIONAL(ENABLE_CXX17, test x$ENABLE_CXX17 = xyes) + dnl Set the list of libraries libabigail depends on DEPS_LIBS="$XML_LIBS $ELF_LIBS $DW_LIBS" -- 2.32.0.288.g62a8d224e6-goog ^ permalink raw reply [flat|nested] 14+ messages in thread
* [PATCH v2 2/6] Tweak clang-format 2021-06-22 10:33 ` [PATCH v2 0/6] BTF ABI Giuliano Procida 2021-06-22 10:33 ` [PATCH v2 1/6] Allow C++17 code to be compiled Giuliano Procida @ 2021-06-22 10:33 ` Giuliano Procida 2021-06-22 10:33 ` [PATCH v2 3/6] BTF: add SCC finder and test Giuliano Procida ` (3 subsequent siblings) 5 siblings, 0 replies; 14+ messages in thread From: Giuliano Procida @ 2021-06-22 10:33 UTC (permalink / raw) To: libabigail; +Cc: dodji, kernel-team, gprocida, maennich The BTF / SCC code is being migrated out of Google source control into AOSP. This comes with the opportunity to migrate the style to be closer libabigail's. In the first instance it makes sense to just reformat it with clang-format. I've updated this as follows. AlignConsecutiveDeclarations: false - as this is closer on average to libgabigail code and looks nicer for the new code anyway AllowShort*: (true) - these in theory should make things closer to libabigail style but in practice don't appear make any difference Cpp11BracedListStyle: true - this seems to improve some initialiser syntax BinPackArguments: false - we already turn this off for parameters SpaceAfterCStyleCast: true - seems to be the libabigail style * .clang-format: Various tweaks for new BTF code. Signed-off-by: Giuliano Procida <gprocida@google.com> --- .clang-format | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/.clang-format b/.clang-format index 1b422dfb..d09d739a 100644 --- a/.clang-format +++ b/.clang-format @@ -2,17 +2,24 @@ --- BasedOnStyle: GNU Standard: c++11 -AlignConsecutiveDeclarations: true +AlignConsecutiveDeclarations: false +AllowShortBlocksOnASingleLine: Always +AllowShortEnumsOnASingleLine: true +AllowShortFunctionsOnASingleLine: All +AllowShortLambdasOnASingleLine: All AlwaysBreakAfterReturnType: All BreakConstructorInitializers: BeforeColon ConstructorInitializerAllOnOneLineOrOnePerLine: true ConstructorInitializerIndentWidth: 2 +Cpp11BracedListStyle: true IndentWidth: 2 AlignAfterOpenBracket: Align +BinPackArguments: false BinPackParameters: false BreakStringLiterals: false PointerAlignment: Left SortUsingDeclarations: false +SpaceAfterCStyleCast: true SpaceBeforeParens: ControlStatements TabWidth: 8 UseTab: Always -- 2.32.0.288.g62a8d224e6-goog ^ permalink raw reply [flat|nested] 14+ messages in thread
* [PATCH v2 3/6] BTF: add SCC finder and test 2021-06-22 10:33 ` [PATCH v2 0/6] BTF ABI Giuliano Procida 2021-06-22 10:33 ` [PATCH v2 1/6] Allow C++17 code to be compiled Giuliano Procida 2021-06-22 10:33 ` [PATCH v2 2/6] Tweak clang-format Giuliano Procida @ 2021-06-22 10:33 ` Giuliano Procida 2021-06-22 10:33 ` [PATCH v2 4/6] BTF: add core functionality Giuliano Procida ` (2 subsequent siblings) 5 siblings, 0 replies; 14+ messages in thread From: Giuliano Procida @ 2021-06-22 10:33 UTC (permalink / raw) To: libabigail; +Cc: dodji, kernel-team, gprocida, maennich The files are almost a straight copy of the originals. Changes: - Files renamed and #includes updated. - Header guards and include order are now in libabigail style. * include/abg-scc.h (SCC): New class to find SCCs. * tests/test-scc.cc: SCC test with randomly-generated graphs. * tests/Makefile.am: Add SCC test, conditional on C++17. Signed-off-by: Giuliano Procida <gprocida@google.com> --- include/abg-scc.h | 111 ++++++++++++++++++++++++++++ tests/Makefile.am | 7 ++ tests/test-scc.cc | 183 ++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 301 insertions(+) create mode 100644 include/abg-scc.h create mode 100644 tests/test-scc.cc diff --git a/include/abg-scc.h b/include/abg-scc.h new file mode 100644 index 00000000..8c542e67 --- /dev/null +++ b/include/abg-scc.h @@ -0,0 +1,111 @@ +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// -*- mode: C++ -*- +// +// Copyright (C) 2020 Google, Inc. +// +// Author: Giuliano Procida + +#ifndef __ABG_SCC_H__ +#define __ABG_SCC_H__ + +#include <cassert> +#include <cstdint> +#include <optional> +#include <unordered_map> +#include <vector> + +namespace abigail { + +/* + * This is a streamlined Strongly-Connected Component finder for use with + * procedurally generated or explored graphs, where the nodes and edges are not + * known a priori. + * + * REQUIREMENTS + * + * The Node type must be copyable and have a suitable hash function. + * + * The user code must take the form of a Depth First Search which can be + * repeatedly invoked on unvisited nodes until the whole graph has been + * traversed. + * + * The user code must always follow edges to child nodes, even if it knows the + * node has already been visited. The SCC finder needs to know about all edges. + * + * The user code must ensure that nodes are not re-examined once they have been + * assigned to an SCC. The finder does not maintain any state for such nodes. + * + * GUARANTEES + * + * The SCC finder will ensure each node is examined exactly once. + * + * The SCCs will be presented in a topological order, leaves first. + * + * Note that within each SCC, nodes will be presented in DFS traversal order, + * roots first. However, this is just an implemention detail, not a guarantee. + * + * USAGE + * + * Before examining a node, check it's not been assigned to an SCC already and + * then call Open. If the node is already "open" (i.e., is already waiting to be + * assigned to an SCC), this will return an empty optional value and the node + * should not be examined. If Open succeeds, a numerical node handle will be + * returned and the node will be recorded as waiting to be assigned to an SCC. + * + * Now examine the node, making recursive calls to follow edges to other nodes. + * Infomation about the node can be stored provisionally, but must NOT be used + * to make decisions about whether to revisit it - that is Open's job. + * + * Once the examination is done, call Close, passing in the handle. If the node + * has been identified as the "root" of an SCC, the whole SCC will be returned + * as a vector of nodes. If any processing needs to be done (such as recording + * the nodes as visited), this should be done now. Otherwise, an empty vector + * will be returned. + */ +template<typename Node, typename Hash = std::hash<Node>> class SCC { + public: + ~SCC() { + assert(open_.empty()); + assert(is_open_.empty()); + assert(root_index_.empty()); + } + + std::optional<size_t> Open(const Node &node) { + // Insertion will fail if the node is already open. + auto [it, inserted] = is_open_.insert({node, is_open_.size()}); + auto ix = it->second; + if (!inserted) { + // Pop indices to nodes which cannot be the root of their SCC. + while (root_index_.back() > ix) + root_index_.pop_back(); + return {}; + } + // Unvisited, record open node and record root index. + open_.push_back(node); + root_index_.push_back(ix); + return ix; + } + + std::vector<Node> Close(size_t ix) { + std::vector<Node> scc; + assert(ix < open_.size()); + if (ix == root_index_.back()) { + // Close SCC. + for (size_t o = ix; o < open_.size(); ++o) + is_open_.erase(open_[o]); + std::move(open_.begin() + ix, open_.end(), std::back_inserter(scc)); + open_.resize(ix); + root_index_.pop_back(); + } + return scc; + } + + private: + std::vector<Node> open_; // index to node + std::unordered_map<Node, size_t, Hash> is_open_; // node to index + std::vector<size_t> root_index_; +}; + +} // namespace abigail + +#endif // __ABG_SCC_H__ diff --git a/tests/Makefile.am b/tests/Makefile.am index 7a3a1f98..95df9542 100644 --- a/tests/Makefile.am +++ b/tests/Makefile.am @@ -53,6 +53,10 @@ else TESTS += runtestdefaultsupprs.py endif +if ENABLE_CXX17 +TESTS += runtestscc +endif + EXTRA_DIST = \ runtestcanonicalizetypes.sh.in \ runtestfedabipkgdiff.py.in \ @@ -166,6 +170,9 @@ testdiff2_LDADD=$(top_builddir)/src/libabigail.la printdifftree_SOURCES = print-diff-tree.cc printdifftree_LDADD = $(top_builddir)/src/libabigail.la +runtestscc_SOURCES = test-scc.cc +runtestscc_LDADD = libcatch.la + runtestslowselfcompare_sh_SOURCES = runtestslowselfcompare.sh$(EXEEXT): diff --git a/tests/test-scc.cc b/tests/test-scc.cc new file mode 100644 index 00000000..a75b1ae0 --- /dev/null +++ b/tests/test-scc.cc @@ -0,0 +1,183 @@ +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// -*- mode: C++ -*- +// +// Copyright (C) 2020 Google, Inc. +// +// Author: Giuliano Procida + +#include <algorithm> +#include <array> +#include <cmath> +#include <iostream> +#include <map> +#include <random> +#include <set> +#include <sstream> +#include <vector> + +#include "lib/catch.hpp" + +#include "abg-scc.h" + +namespace Test { + +using abigail::SCC; + +// Nodes are [0, N), the sets are the out-edges. +typedef std::vector<std::set<size_t>> Graph; + +std::ostream &operator<<(std::ostream &os, const Graph &g) { + for (size_t i = 0; i < g.size(); ++i) { + os << i << ':'; + for (auto o : g[i]) + os << ' ' << o; + os << '\n'; + } + return os; +} + +template<typename G> Graph invent(size_t n, G& gen) { + Graph graph(n); + std::uniform_int_distribution<int> toss(0, 1); + for (auto &node : graph) { + for (size_t o = 0; o < n; ++o) { + if (toss(gen)) + node.insert(o); + } + } + return graph; +} + +// Generate a graph g' where a -> b iff a and b are strongly connected in g. +Graph symmetric_subset_of_reflexive_transitive_closure(Graph g) { + const size_t n = g.size(); + // transitive closure using Floyd-Warshall + for (size_t o = 0; o < n; ++o) + g[o].insert(o); + for (size_t k = 0; k < n; ++k) { + for (size_t i = 0; i < n; ++i) { + for (size_t j = 0; j < n; ++j) { + if (!g[i].count(j) && g[i].count(k) && g[k].count(j)) + g[i].insert(j); + } + } + } + // now a -> b iff a has path to b in g + for (size_t i = 0; i < n; ++i) { + for (size_t j = i + 1; j < n; ++j) { + // discard a -> b if not b -> a and vice versa + auto ij = g[i].count(j); + auto ji = g[j].count(i); + if (ij < ji) g[j].erase(i); + if (ji < ij) g[i].erase(j); + } + } + // now have a -> b iff a has path to b and b has path to a in g + return g; +} + +// Generate a graph where a -> b iff a and b are in the same SCC. +Graph scc_strong_connectivity(const std::vector<std::set<size_t>> &sccs) { + size_t n = 0; + std::map<size_t, const std::set<size_t> *> edges; + for (const auto &scc : sccs) { + for (auto o : scc) { + if (o >= n) + n = o + 1; + edges[o] = &scc; + } + } + Graph g(n); + for (size_t o = 0; o < n; ++o) + g[o] = *edges[o]; + return g; +} + +void dfs(std::set<size_t> &visited, SCC<size_t> &scc, + const Graph &g, size_t node, + std::vector<std::set<size_t>> &sccs) { + if (visited.count(node)) + return; + auto handle = scc.Open(node); + if (!handle) + return; + for (auto o : g[node]) + dfs(visited, scc, g, o, sccs); + auto nodes = scc.Close(handle.value()); + if (!nodes.empty()) { + std::set<size_t> scc_set; + for (auto o : nodes) { + CHECK(visited.insert(o).second); + CHECK(scc_set.insert(o).second); + } + sccs.push_back(scc_set); + } +} + +void process(const Graph &g) { + const size_t n = g.size(); + + // find SCCs + std::set<size_t> visited; + SCC<size_t> scc; + std::vector<std::set<size_t>> sccs; + for (size_t o = 0; o < n; ++o) + dfs(visited, scc, g, o, sccs); + + // check partition and topological order properties + std::set<size_t> seen; + for (const auto &nodes : sccs) { + CHECK(!nodes.empty()); + for (auto node : nodes) { + // value in range [0, n) + CHECK(node < n); + // value seen at most once + CHECK(seen.insert(node).second); + } + for (auto node : nodes) { + for (auto o : g[node]) { + // edges point to nodes in this or earlier SCCs + CHECK(seen.count(o)); + } + } + } + // exactly n values seen + CHECK(seen.size() == n); + + // check strong connectivity + auto g_scc_closure = scc_strong_connectivity(sccs); + auto g_closure = symmetric_subset_of_reflexive_transitive_closure(g); + // catch isn't printing nicely + if (g_scc_closure != g_closure) { + std::cerr << "original:\n" << g + << "SCC finder:\n" << g_scc_closure + << "SCCs independently:\n" << g_closure; + } + CHECK(g_scc_closure == g_closure); +} + +TEST_CASE("randomly-generated graphs") { + std::mt19937 gen; + auto seed = gen(); + // NOTES: + // Graphs of size 6 are plenty big enough to shake out bugs. + // There are O(2^k^2) possible directed graphs of size k. + // Testing costs are O(k^3) so we restrict accordingly. + uint64_t budget = 10000; + for (size_t k = 0; k < 7; ++k) { + uint64_t count = std::min(static_cast<uint64_t>(1) << (k*k), + budget / (k ? k * k * k : 1)); + INFO("testing with " << count << " graphs of size " << k); + for (uint64_t n = 0; n < count; ++n, ++seed) { + gen.seed(seed); + Graph g = invent(k, gen); + std::ostringstream os; + os << "a graph of " << k << " nodes generated using seed " << seed; + GIVEN(os.str()) { + process(g); + } + } + } +} + +} // namespace Test -- 2.32.0.288.g62a8d224e6-goog ^ permalink raw reply [flat|nested] 14+ messages in thread
* [PATCH v2 4/6] BTF: add core functionality 2021-06-22 10:33 ` [PATCH v2 0/6] BTF ABI Giuliano Procida ` (2 preceding siblings ...) 2021-06-22 10:33 ` [PATCH v2 3/6] BTF: add SCC finder and test Giuliano Procida @ 2021-06-22 10:33 ` Giuliano Procida 2021-06-22 10:33 ` [PATCH v2 5/6] BTF: add btfinfo and btfdiff tools Giuliano Procida 2021-06-22 10:33 ` [PATCH v2 6/6] BTF: clang-format all the new source files Giuliano Procida 5 siblings, 0 replies; 14+ messages in thread From: Giuliano Procida @ 2021-06-22 10:33 UTC (permalink / raw) To: libabigail; +Cc: dodji, kernel-team, gprocida, maennich, Maria Teguiani This commit adds core BTF functionality. The code can: - read ELF symbols using the symtab_reader - read BTF into a graph of type and symbol information - optionally perform a text dump of BTF as it's read - compute diffs between two BTF graphs as a diff graph - done using DFS and with the help of the SCC finder - create and cache full names for types - serialise a diff graph as a textual diff report - done using DFS The files are almost a straight copy of the originals. Changes: - Files renamed and #includes updated. - Header guards and include order are now in libabigail style. * COMPILING: Add note about BTF dependency. * configure.ac: Add check for <linux/btf.h>. * src/Makefile.am: Add abg-btf.cc, conditional on C++17 and presence of <linux/btf.h>. * include/abg-btf.h: New file. * src/abg-btf.cc: New file. Co-authored-by: Maria Teguiani <teguiani@google.com> Signed-off-by: Giuliano Procida <gprocida@google.com> --- COMPILING | 5 + configure.ac | 7 + include/abg-btf.h | 582 +++++++++++++++++++ src/Makefile.am | 9 +- src/abg-btf.cc | 1369 +++++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 1971 insertions(+), 1 deletion(-) create mode 100644 include/abg-btf.h create mode 100644 src/abg-btf.cc diff --git a/COMPILING b/COMPILING index 33613a37..75a6588a 100644 --- a/COMPILING +++ b/COMPILING @@ -5,6 +5,11 @@ the moment the dependencies are the following Free Software packages: libtool libxml2 +To build the BTF tools, you will need <linux/btf.h> which can be found +in the development package of: + + linux-libc + If you are building from the Git repository, then you'd also need the following packages: diff --git a/configure.ac b/configure.ac index edd03cf8..d9125d99 100644 --- a/configure.ac +++ b/configure.ac @@ -603,6 +603,13 @@ if test x$ENABLE_CXX17 = xyes; then fi AM_CONDITIONAL(ENABLE_CXX17, test x$ENABLE_CXX17 = xyes) +dnl Check for the presence of the BTF header. +HAVE_BTF=no +AC_CHECK_HEADER([linux/btf.h], + [HAVE_BTF=yes], + [AC_MSG_NOTICE([No linux/btf.h found, omitted BTF support.])]) +AM_CONDITIONAL(HAVE_BTF, test x$HAVE_BTF = xyes) + dnl Set the list of libraries libabigail depends on DEPS_LIBS="$XML_LIBS $ELF_LIBS $DW_LIBS" diff --git a/include/abg-btf.h b/include/abg-btf.h new file mode 100644 index 00000000..f7243fa3 --- /dev/null +++ b/include/abg-btf.h @@ -0,0 +1,582 @@ +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// -*- mode: C++ -*- +// +// Copyright (C) 2020-2021 Google, Inc. +// +// Author: Maria Teguiani +// Author: Giuliano Procida + +#ifndef __ABG_BTF_H__ +#define __ABG_BTF_H__ + +#include <fcntl.h> +#include <linux/btf.h> + +#include <cstdint> +#include <cstdlib> +#include <iostream> +#include <map> +#include <set> +#include <sstream> +#include <string> +#include <unordered_map> +#include <unordered_set> +#include <vector> + +#include "abg-ir.h" +#include "abg-scc.h" + +namespace abigail { +namespace btf { + +#define m_assert(expr, msg) assert(((void)(msg), (expr))) + +using Kind = uint32_t; + +// A Member refers to a data element of a struct or union, used in the context +// of StructUnion +struct Member { + uint32_t typeId_; + uint32_t offset_; + uint32_t bitfieldSize_; +}; + +// A Parameter refers to a variable declared in the function declaration, used +// in the context of Function +struct Parameter { + std::string name_; + uint32_t typeId_; +}; + +struct Secinfo { + uint32_t typeId_; + uint32_t offset_; + uint32_t bytesize_; +}; + +enum class ForwardDeclarationKind { STRUCT, UNION }; + +std::ostream &operator<<(std::ostream &os, ForwardDeclarationKind kind); + +class Type; + +using Comparison = std::pair<const Type *, const Type *>; + +enum class Precedence { NIL, POINTER, ARRAY_FUNCTION, ATOMIC }; +enum class Side { LEFT, RIGHT }; + +class Name { + public: + explicit Name(const std::string &name) + : left_(name), precedence_(Precedence::NIL), right_() {} + Name(const std::string &left, Precedence precedence, const std::string &right) + : left_(left), precedence_(precedence), right_(right) {} + Name Add(Side side, Precedence precedence, const std::string &text) const; + Name Qualify(const std::set<Kind> &qualifiers) const; + std::ostream &Print(std::ostream &os) const; + + private: + std::string left_; + Precedence precedence_; + std::string right_; +}; + +std::ostream &operator<<(std::ostream &os, const Name &name); + +using NameCache = std::unordered_map<const Type *, Name>; + +struct DiffDetail { + DiffDetail(const std::string &text, const std::optional<Comparison> &edge) + : text_(text), edge_(edge) {} + std::string text_; + std::optional<Comparison> edge_; +}; + +using Diff = std::vector<DiffDetail>; + +struct Result { + void AddDiff(const std::string &text) { + equals_ = false; + details_.emplace_back(text, std::optional<Comparison>()); + } + + void AddDiff(const std::string &text, Comparison comparison) { + equals_ = false; + details_.emplace_back(text, comparison); + } + + void MaybeAddDiff(const std::string &text, + const std::pair<bool, std::optional<Comparison>> &p) { + equals_ &= p.first; + const auto &diff = p.second; + if (diff) + details_.emplace_back(text, diff); + } + + // Maximally powerful lazy version, takes a function that outputs an "edge" + // diff description, to be used only when a diff is present. + void MaybeAddDiff(std::function<void(std::ostream &)> text, + const std::pair<bool, std::optional<Comparison>> &p) { + equals_ &= p.first; + const auto &diff = p.second; + if (diff) { + std::ostringstream os; + text(os); + details_.emplace_back(os.str(), diff); + } + } + + template<typename T> void MaybeAddDiff( + const std::string &text, const T &before, const T &after) { + if (before != after) { + equals_ = false; + std::ostringstream os; + os << text << " changed from " << before << " to " << after; + AddDiff(os.str()); + } + } + + // Lazy version. + template<typename T> void MaybeAddDiff( + std::function<void(std::ostream &)> text, + const T &before, const T &after) { + if (before != after) { + equals_ = false; + std::ostringstream os; + text(os); + os << " changed from " << before << " to " << after; + AddDiff(os.str()); + } + } + + bool equals_ = true; + Diff details_; +}; + +struct HashComparison { + size_t operator()(const Comparison &comparison) const { + size_t seed = 0; + std::hash<const Type *> h; + combine_hash(seed, h(comparison.first)); + combine_hash(seed, h(comparison.second)); + return seed; + } + static void combine_hash(size_t &seed, size_t hash) { + seed ^= hash + 0x9e3779b97f4a7c15 + (seed << 12) + (seed >> 4); + } +}; + +using Outcomes = std::unordered_map<Comparison, Diff, HashComparison>; +// unvisited (absent) -> started (false) -> finished (true) +using Seen = std::unordered_map<Comparison, bool, HashComparison>; + +void Print(const Comparison &comparison, const Outcomes &outcomes, Seen &seen, + NameCache &names, std::ostream &os, size_t indent = 0); + +void Print(const Diff &details, const Outcomes &outcomes, Seen &seen, + NameCache &names, std::ostream &os, size_t indent = 0); + +class Type { + public: + Type(const std::vector<std::unique_ptr<Type>> &types, uint32_t index, + Kind kind) + : types_(types), index_(index), kind_(kind) {} + virtual ~Type() = default; + uint32_t GetIndex() const { return index_; } + Kind GetKind() const { return kind_; } + const std::vector<std::unique_ptr<Type>> &GetTypes() const { + return types_; + } + + // as<Type>() provides a method to defer downcasting to the base class, + // instead of needing to use dynamic_cast in a local context. If the type is + // not correct, the assert will trigger in debug mode. In release mode, this + // will crash dereferencing the nullptr. + template <typename Target> + const Target &as() const { + static_assert(std::is_convertible<Target *, Type *>::value, + "Target must publically inherit Type"); + const Target *t = dynamic_cast<const Target *>(this); + m_assert(t, "Invalid downcast"); + return *t; + } + // Separate qualifiers from underlying type. + // + // The caller must always be prepared to receive a different type as + // qualifiers are sometimes discarded. + virtual const Type &ResolveQualifiers(std::set<Kind> &qualifiers) const; + virtual const Type &ResolveTypedef( + std::vector<std::string> &typedefs) const; + + const Name &GetDescription(NameCache &names) const; + static Result CompareSymbols( + const std::map<std::string, const Type *const> &lhs, + const std::map<std::string, const Type *const> &rhs, + Outcomes &outcomes); + + protected: + struct State { + explicit State(Outcomes &o) : outcomes(o) { } + Outcomes &outcomes; + std::unordered_set<Comparison, HashComparison> known_equal; + Outcomes provisional; + SCC<Comparison, HashComparison> scc; + }; + const Type &GetTypeAtIndex(size_t index) const; + + virtual Name MakeDescription(NameCache &names) const = 0; + virtual Result Equals(const Type &other, State &state) const = 0; + static Comparison Removed(const Type &lhs, State &state); + static Comparison Added(const Type &rhs, State &state); + static std::pair<bool, std::optional<Comparison>> Compare( + const Type &lhs, const Type &rhs, State &state); + + private: + static std::string GetDiffMessage(NameCache &names, + const Type &lhs, const Type &rhs, + const std::string &message = std::string()); + const std::vector<std::unique_ptr<Type>> &types_; + const uint32_t index_; + const Kind kind_; +}; + +class Void : public Type { + public: + Void(const std::vector<std::unique_ptr<Type>> &types, uint32_t index, + Kind kind) + : Type(types, index, kind) {} + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; +}; + +class Ptr : public Type { + public: + Ptr(const std::vector<std::unique_ptr<Type>> &types, uint32_t index, + Kind kind, uint32_t pointeeTypeId) + : Type(types, index, kind), + pointeeTypeId_(pointeeTypeId) {} + uint32_t GetPointeeTypeId() const { return pointeeTypeId_; } + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; + + private: + const uint32_t pointeeTypeId_; +}; + +class Typedef : public Type { + public: + Typedef(const std::vector<std::unique_ptr<Type>> &types, uint32_t index, + const std::string &name, Kind kind, uint32_t referredTypeId) + : Type(types, index, kind), + name_(name), + referredTypeId_(referredTypeId) {} + const std::string &GetName() const { return name_; } + uint32_t GetReferredTypeId() const { return referredTypeId_; } + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; + const Type &ResolveTypedef( + std::vector<std::string> &typedefs) const final; + + private: + const std::string name_; + const uint32_t referredTypeId_; +}; + +class Qualifier : public Type { + public: + Qualifier(const std::vector<std::unique_ptr<Type>> &types, + uint32_t index, Kind kind, uint32_t qualifiedTypeId) + : Type(types, index, kind), + qualifiedTypeId_(qualifiedTypeId) {} + uint32_t GetQualifiedTypeId() const { return qualifiedTypeId_; } + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; + const Type &ResolveQualifiers(std::set<Kind> &qualifiers) const final; + + private: + const uint32_t qualifiedTypeId_; +}; + +class Integer : public Type { + public: + Integer(const std::vector<std::unique_ptr<Type>> &types, uint32_t index, + const std::string &name, Kind kind, uint32_t encoding, + uint32_t offset, uint32_t bitsize, uint32_t bytesize) + : Type(types, index, kind), + name_(name), + offset_(offset), + bitsize_(bitsize), + bytesize_(bytesize), + isBool_(encoding & BTF_INT_BOOL), + isSigned_(encoding & BTF_INT_SIGNED), + isChar_(encoding & BTF_INT_CHAR) {} + const std::string &GetName() const { return name_; } + bool isBool() const { return isBool_; } + bool isSigned() const { return isSigned_; } + bool isChar() const { return isChar_; } + uint32_t GetOffset() const { return offset_; } + + // GetBitSize() gives the semantics of the field. GetByteSize() gives the + // storage size, and is equal or greater than GetBitSize()*8 + uint32_t GetBitSize() const { return bitsize_; } + uint32_t GetByteSize() const { return bytesize_; } + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; + + private: + const std::string name_; + const uint32_t offset_; + const uint32_t bitsize_; + const uint32_t bytesize_; + const bool isBool_; + const bool isSigned_; + const bool isChar_; +}; + +class Array : public Type { + public: + Array(const std::vector<std::unique_ptr<Type>> &types, uint32_t index, + Kind kind, uint32_t elementTypeId, uint32_t indexTypeId, + uint32_t numOfElements) + : Type(types, index, kind), + elementTypeId_(elementTypeId), + indexTypeId_(indexTypeId), + numOfElements_(numOfElements) {} + uint32_t GetElementTypeId() const { return elementTypeId_; } + uint32_t GetIndexTypeId() const { return indexTypeId_; } + uint32_t GetNumberOfElements() const { return numOfElements_; } + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; + + private: + const uint32_t elementTypeId_; + const uint32_t indexTypeId_; + const uint32_t numOfElements_; +}; + +class StructUnion : public Type { + public: + StructUnion(const std::vector<std::unique_ptr<Type>> &types, + uint32_t index, const std::string &name, Kind kind, + uint32_t bytesize, std::map<std::string, Member> members) + : Type(types, index, kind), + name_(name), + bytesize_(bytesize), + members_(members) {} + const std::string &GetName() const { return name_; } + uint32_t GetByteSize() const { return bytesize_; } + const std::map<std::string, Member> &GetMembers() const { return members_; } + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; + + private: + const std::string name_; + const uint32_t bytesize_; + const std::map<std::string, Member> members_; +}; + +class Enumeration : public Type { + public: + Enumeration(const std::vector<std::unique_ptr<Type>> &types, + uint32_t index, const std::string &name, Kind kind, + uint32_t bytesize, std::map<std::string, int> enumerators) + : Type(types, index, kind), + name_(name), + bytesize_(bytesize), + enumerators_(enumerators) {} + const std::string &GetName() const { return name_; } + uint32_t GetByteSize() const { return bytesize_; } + const std::map<std::string, int> &GetEnums() const { return enumerators_; } + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; + + private: + const std::string name_; + const uint32_t bytesize_; + const std::map<std::string, int> enumerators_; +}; + +// BTF only considers structs and unions as forward-declared types, and does not +// include forward-declared enums. They are treated as BTF_KIND_ENUMs with vlen +// set to zero +class ForwardDeclaration : public Type { + public: + ForwardDeclaration(const std::vector<std::unique_ptr<Type>> &types, + uint32_t index, const std::string &name, Kind kind, + bool isUnion) + : Type(types, index, kind), + name_(name), + fwdKind_(isUnion ? ForwardDeclarationKind::UNION + : ForwardDeclarationKind::STRUCT) {} + const std::string &GetName() const { return name_; } + ForwardDeclarationKind GetFwdKind() const { return fwdKind_; } + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; + + private: + const std::string name_; + const ForwardDeclarationKind fwdKind_; +}; + +class Function : public Type { + public: + enum class Linkage : uint16_t { STATIC, GLOBAL, EXTERN }; + Function(const std::vector<std::unique_ptr<Type>> &types, + uint32_t index, const std::string &name, Kind kind, + uint32_t referredTypeId, Linkage linkage) + : Type(types, index, kind), + name_(name), + referredTypeId_(referredTypeId), + linkage_(linkage) {} + const std::string &GetName() const { return name_; } + uint32_t GetReferredTypeId() const { return referredTypeId_; } + Linkage GetLinkage() const { return linkage_; } + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; + + private: + const std::string name_; + const uint32_t referredTypeId_; + const Linkage linkage_; +}; + +class FunctionPrototype : public Type { + public: + FunctionPrototype(const std::vector<std::unique_ptr<Type>> &types, + uint32_t index, Kind kind, uint32_t returnTypeId, + std::vector<Parameter> parameters) + : Type(types, index, kind), + returnTypeId_(returnTypeId), + parameters_(parameters) {} + uint32_t GetReturnTypeId() const { return returnTypeId_; } + const std::vector<Parameter> &GetParameters() const { return parameters_; } + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; + + private: + const uint32_t returnTypeId_; + const std::vector<Parameter> parameters_; +}; + +class Variable : public Type { + public: + enum class Linkage : uint32_t { STATIC, GLOBAL_ALLOC, GLOBAL_EXTERN }; + Variable(const std::vector<std::unique_ptr<Type>> &types, + uint32_t index, const std::string &name, Kind kind, + unsigned varTypeId, Linkage linkage) + : Type(types, index, kind), + name_(name), + varTypeId_(varTypeId), + linkage_(linkage) {} + const std::string &GetName() const { return name_; } + uint32_t GetVarTypeId() const { return varTypeId_; } + Linkage GetLinkage() const { return linkage_; } + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; + + private: + const std::string name_; + const uint32_t varTypeId_; + const Linkage linkage_; +}; + +class DataSection : public Type { + public: + DataSection(const std::vector<std::unique_ptr<Type>> &types, + uint32_t index, Kind kind, uint32_t bytesize, + std::vector<Secinfo> secinfos) + : Type(types, index, kind), + bytesize_(bytesize), + secinfos_(secinfos) {} + uint32_t GetByteSize() const { return bytesize_; } + const std::vector<Secinfo> &GetSecinfos() const { return secinfos_; } + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; + + private: + const uint32_t bytesize_; + const std::vector<Secinfo> secinfos_; +}; + +// Not actually a BTF type but needed for uniformity of representation. +class ElfSymbol : public Type { + public: + ElfSymbol(const std::vector<std::unique_ptr<Type>> &types, + abigail::elf_symbol_sptr symbol, uint32_t type_id) + : Type(types, -1, -1), symbol_(symbol), type_id_(type_id) {} + abigail::elf_symbol_sptr GetElfSymbol() const { return symbol_; } + uint32_t GetTypeId() const { return type_id_; } + Name MakeDescription(NameCache &names) const final; + Result Equals(const Type &other, State &state) const final; + + private: + abigail::elf_symbol_sptr symbol_; + uint32_t type_id_; +}; + +std::ostream &operator<<(std::ostream &os, const Ptr &bp); +std::ostream &operator<<(std::ostream &os, const Typedef &bp); +std::ostream &operator<<(std::ostream &os, const Qualifier &bp); +std::ostream &operator<<(std::ostream &os, const Integer &bi); +std::ostream &operator<<(std::ostream &os, const Array &ba); +std::ostream &operator<<(std::ostream &os, const StructUnion &bsu); +std::ostream &operator<<(std::ostream &os, const Enumeration &be); +std::ostream &operator<<(std::ostream &os, const ForwardDeclaration &bfd); +std::ostream &operator<<(std::ostream &os, const Function &bf); +std::ostream &operator<<(std::ostream &os, const FunctionPrototype &bfp); +std::ostream &operator<<(std::ostream &os, const Variable &bv); +std::ostream &operator<<(std::ostream &os, const DataSection &bds); +std::ostream &operator<<(std::ostream &os, const ElfSymbol &bes); +std::ostream &operator<<(std::ostream &os, Variable::Linkage linkage); +std::ostream &operator<<(std::ostream &os, Function::Linkage linkage); + +// BTF Specification: https://www.kernel.org/doc/html/latest/bpf/btf.html +class Structs { + public: + Structs(const char *start, std::unique_ptr<abigail::ir::environment> env, + const abigail::symtab_reader::symtab_sptr tab, + const bool verbose = false); + ~Structs() = default; + void PrintHeader(); + void BuildTypes(); + void PrintStringSection(); + const std::map<std::string, const Type *const> &GetSymbols( + bool use_elf_symbols) const { + return use_elf_symbols ? elf_symbols_ : btf_symbols_; + } + + private: + const btf_header *header_; + const btf_type *type_section_; + const char *str_section_; + const std::unique_ptr<abigail::ir::environment> env_; + const abigail::symtab_reader::symtab_sptr tab_; + const bool verbose_; + + std::vector<std::unique_ptr<Type>> types_; + std::unordered_map<std::string, uint32_t> btf_symbol_types_; + std::map<std::string, const Type *const> btf_symbols_; + std::map<std::string, const Type *const> elf_symbols_; + + std::vector<std::string> bad_names_; + std::string bad_prefix_1_; + std::string bad_prefix_2_; + + int BuildOneType(const btf_type *t, uint32_t index); + void BuildElfSymbols(); + std::map<std::string, Member> BuildMembers( + bool kflag, const btf_member *members, size_t vlen); + std::map<std::string, int> BuildEnums(const struct btf_enum *enums, + size_t vlen); + std::vector<Parameter> BuildParams(const struct btf_param *params, + size_t vlen); + std::vector<Secinfo> BuildDatasec(const btf_type *type, size_t vlen); + std::string GetName(uint32_t name_off); +}; + +Structs ReadFile(const std::string &path, bool verbose = false); + +} // end namespace btf +} // end namespace abigail + +#endif // __ABG_BTF_H__ diff --git a/src/Makefile.am b/src/Makefile.am index 430ce98d..d67c604c 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -8,6 +8,12 @@ VIZ_SOURCES = abg-viz-common.cc \ abg-viz-dot.cc \ abg-viz-svg.cc +if ENABLE_CXX17 +if HAVE_BTF + BTF_SOURCES = abg-btf.cc +endif +endif + libabigail_la_SOURCES = \ abg-internal.h \ abg-traverse.cc \ @@ -39,7 +45,8 @@ abg-elf-helpers.cc \ abg-regex.cc \ abg-symtab-reader.h \ abg-symtab-reader.cc \ -$(VIZ_SOURCES) +$(VIZ_SOURCES) \ +$(BTF_SOURCES) libabigail_la_LIBADD = $(DEPS_LIBS) libabigail_la_LDFLAGS = -lpthread -Wl,--as-needed -no-undefined diff --git a/src/abg-btf.cc b/src/abg-btf.cc new file mode 100644 index 00000000..39a8e480 --- /dev/null +++ b/src/abg-btf.cc @@ -0,0 +1,1369 @@ +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// -*- mode: C++ -*- +// +// Copyright (C) 2020-2021 Google, Inc. +// +// Author: Maria Teguiani +// Author: Giuliano Procida + +#include <elfutils/libdwfl.h> + +#include <algorithm> +#include <array> +#include <iomanip> +#include <set> +#include <sstream> +#include <string_view> + +#include "abg-elf-helpers.h" +#include "abg-symtab-reader.h" +#include "abg-tools-utils.h" + +#include "abg-btf.h" + +namespace abigail { +namespace btf { + +// This is a helper map that yields the name of a Type in the preferred +// print style by indexing into the vector with a Kind +static constexpr std::array<std::string_view, 16> kKindNames = { + "void type", + "integer type", + "pointer type", + "array type", + "struct type", + "union type", + "enum type", + "forward declaration", + "typedef", + "volatile", + "const", + "restrict", + "function", + "function type", + "variable", + "data section" +}; + +// This matches bpftool dump format raw. +static constexpr std::array<std::string_view, 16> kRawKindNames = { + "VOID", + "INT", + "PTR", + "ARRAY", + "STRUCT", + "UNION", + "ENUM", + "FWD", + "TYPEDEF", + "VOLATILE", + "CONST", + "RESTRICT", + "FUNC", + "FUNC_PROTO", + "VAR", + "DATASEC" +}; + +static constexpr std::array<std::string_view, 3> kVarLinkage = { + "static", + "global-alloc", + "global-extern" // NOTE: bpftool currently says "(unknown)" +}; + +static constexpr std::array<std::string_view, 3> kFunLinkage = { + "static", + "global", + "extern" +}; + +Name Name::Add(Side side, Precedence precedence, + const std::string &text) const { + bool bracket = precedence < precedence_; + std::ostringstream left; + std::ostringstream right; + + // Bits on the left need (sometimes) to be separated by whitespace. + left << left_; + if (bracket) + left << '('; + else if (side == Side::LEFT) + left << ' '; + + (side == Side::LEFT ? left : right) << text; + + // Bits on the right are arrays [] and functions () and need no whitespace. + if (bracket) + right << ')'; + right << right_; + + return Name{left.str(), precedence, right.str()}; +} + +Name Name::Qualify(const std::set<Kind> &qualifiers) const { + // this covers the case when bad qualifiers have been dropped + if (qualifiers.empty()) + return *this; + // add qualifiers to the left or right of the type stem + std::ostringstream os; + if (precedence_ == Precedence::NIL) { + for (const auto &qualifier : qualifiers) + os << kKindNames[qualifier] << ' '; + os << left_; + } else if (precedence_ == Precedence::POINTER) { + os << left_; + for (const auto &qualifier : qualifiers) + os << ' ' << kKindNames[qualifier]; + } else { + m_assert(false, "unqualifiable element"); + } + // qualifiers attach without affecting precedence + return Name{os.str(), precedence_, right_}; +} + +std::ostream &Name::Print(std::ostream &os) const { + return os << left_ << right_; +} + +std::ostream &operator<<(std::ostream &os, const Name &name) { + return name.Print(os); +} + +// There are several reasons for treating CV-qualifiers specially. +// 1. They upset the precedence scheme we've got going here. +// 2. Qualifiers need to be placed according to what they qualify. +// 3. The BTF model doesn't preclude ordering and duplication issues. +// 4. A better model would have qualifiers as part of the types. +const Name &Type::GetDescription(NameCache &names) const { + // infinite recursion prevention - insert at most once + static const Name black_hole{"#"}; + + auto insertion = names.insert({this, black_hole}); + Name &cached = insertion.first->second; + + if (insertion.second) { + // newly inserted, need to determine name of type + std::set<Kind> qualifiers; + const Type &under = ResolveQualifiers(qualifiers); + if (this == &under) { + // unqualified, simple case + cached = MakeDescription(names); + } else { + // qualified, but we may end up adding no qualifiers + auto insertion_under = names.insert({&under, black_hole}); + Name &cached_under = insertion_under.first->second; + + // newly inserted underlying type name + if (insertion_under.second) + cached_under = under.MakeDescription(names); + + // add the qualifiers (to the appropriate side) + cached = cached_under.Qualify(qualifiers); + } + } + + return cached; +} + +std::string GetPlainDescription(NameCache &names, const Type &type) { + std::ostringstream os; + os << '"' << type.GetDescription(names) << '"'; + return os.str(); +} + +std::string GetTypedefDescription(NameCache &names, const Type &given) { + std::ostringstream os; + std::vector<std::string> typedefs; + const Type &type = given.ResolveTypedef(typedefs); + for (auto td : typedefs) + os << std::quoted(td) << " = "; + os << GetPlainDescription(names, type); + return os.str(); +} + +constexpr size_t INDENT_INCREMENT = 2; + +void Print(const Comparison &comparison, const Outcomes &outcomes, Seen &seen, + NameCache &names, std::ostream &os, size_t indent) { + const auto *lhs = comparison.first; + const auto *rhs = comparison.second; + if (!rhs) { + os << GetPlainDescription(names, *lhs) << " was removed\n"; + return; + } + if (!lhs) { + os << GetPlainDescription(names, *rhs) << " was added\n"; + return; + } + bool td = lhs->GetKind() == BTF_KIND_TYPEDEF + || rhs->GetKind() == BTF_KIND_TYPEDEF; + const std::string lhs_descr = td ? GetTypedefDescription(names, *lhs) + : GetPlainDescription(names, *lhs); + const std::string rhs_descr = td ? GetTypedefDescription(names, *rhs) + : GetPlainDescription(names, *rhs); + if (lhs_descr == rhs_descr) + os << lhs_descr << " changed"; + else + os << "changed from " << lhs_descr << " to " << rhs_descr; + const auto &details = outcomes.find(comparison)->second; + auto insertion = seen.insert({comparison, false}); + if (!insertion.second) { + if (!insertion.first->second) + os << " (being reported)"; + else if (!details.empty()) + os << " (already reported)"; + } + os << '\n'; + if (insertion.second) { + Print(details, outcomes, seen, names, os, indent + INDENT_INCREMENT); + insertion.first->second = true; + } + // paragraph spacing + if (!indent) + os << '\n'; +} + +void Print(const Diff &details, const Outcomes &outcomes, Seen &seen, + NameCache &names, std::ostream &os, size_t indent) { + for (const auto &detail : details) { + os << std::string(indent, ' ') << detail.text_; + if (!detail.edge_) { + os << '\n'; + } else { + os << ' '; + Print(detail.edge_.value(), outcomes, seen, names, os, indent); + } + } +} + +const Type &Type::GetTypeAtIndex(size_t index) const { + m_assert(index < types_.size(), "Index out of bounds."); + return *(types_[index].get()); +} + +std::string QualifiersMessage(Kind qualifier, const std::string &action) { + std::ostringstream os; + os << "qualifier " << kKindNames[qualifier] << ' ' << action; + return os.str(); +} + +Result Type::CompareSymbols( + const std::map<std::string, const Type *const> &lhs, + const std::map<std::string, const Type *const> &rhs, + Outcomes &outcomes) { + Result result; + State state(outcomes); + auto lit = lhs.begin(); + auto rit = rhs.begin(); + // Each branch contains a NULL pointer check in case BTF information is + // missing for a symbol. We conservatively have to assume that any symbol + // without BTF information may have changed type. + // + // NOTE: this currently happens for all global variables + while (lit != lhs.end() || rit != rhs.end()) { + if (rit == rhs.end() || (lit != lhs.end() && lit->first < rit->first)) { + // removed + if (lit->second) { + auto diff = Removed(*lit->second, state); + result.AddDiff("symbol", diff); + } else { + std::ostringstream os; + os << "symbol " << std::quoted(lit->first) + << " (of unknown type) was removed"; + result.AddDiff(os.str()); + } + ++lit; + } else if (lit == lhs.end() || (rit != rhs.end() && lit->first > rit->first)) { + // added + if (rit->second) { + auto diff = Added(*rit->second, state); + result.AddDiff("symbol", diff); + } else { + std::ostringstream os; + os << "symbol " << std::quoted(rit->first) + << " (if unknown type) was added"; + result.AddDiff(os.str()); + } + ++rit; + } else { + // in both + if (lit->second && rit->second) { + auto diff = Compare(*lit->second, *rit->second, state); + result.MaybeAddDiff("symbol", diff); + } else { + std::ostringstream os; + os << "symbol " << std::quoted(lit->first) + << " (of unknown type) may have changed"; + result.AddDiff(os.str()); + } + ++lit; + ++rit; + } + } + return result; +} + +Comparison Type::Removed(const Type &lhs, State &state) { + Comparison comparison{&lhs, nullptr}; + state.outcomes.insert({comparison, {}}); + return comparison; +} + +Comparison Type::Added(const Type &rhs, State &state) { + Comparison comparison{nullptr, &rhs}; + state.outcomes.insert({comparison, {}}); + return comparison; +} + +/* + * We compute a diff for every visited node. + * + * Each node has one of: + * 1. equals = true; perhaps only tentative edge differences + * 2. equals = false; at least one definitive node or edge difference + * + * On the first visit to a node we can put a placeholder in, the equals value is + * irrelevant, the diff may contain local and edge differences. If an SCC + * contains only internal edge differences (and equivalently equals is true) + * then the differences can all (eventually) be discarded. + * + * On exit from the first visit to a node, equals reflects the tree of + * comparisons below that node in the DFS and similarly, the diff graph starting + * from the node contains a subtree of this tree plus potentially edges to + * existing nodes to the side or below (already visited SCCs, sharing), or above + * (back links forming cycles). + * + * When an SCC is closed, all equals implies deleting all diffs, any false + * implies updating all to false. + * + * On subsequent visits to a node, there are 2 cases. The node is still open: + * return true and an edge diff. The node is closed, return the stored value and + * an edge diff. + */ +std::pair<bool, std::optional<Comparison>> Type::Compare( + const Type &lhs, const Type &rhs, Type::State &state) { + const Comparison comparison{&lhs, &rhs}; + + // 1. Check if the comparison has an already known result. + if (state.known_equal.count(comparison)) { + // Already visited and closed. Equal. + return {true, {}}; + } + if (state.outcomes.count(comparison)) { + // Already visited and closed. Different. + return {false, {comparison}}; + } + // Either open or not visited at all + + // 2. Record node with Strongly-Connected Component finder. + auto handle = state.scc.Open(comparison); + if (!handle) { + // Already open. + // + // Return a dummy true outcome and some tentative diffs. The diffs may end + // up not being used and, while it would be nice to be lazier, they encode + // all the cycling-breaking edges needed to recreate a full diff structure. + return {true, {comparison}}; + } + // Comparison opened, need to close it before returning. + + Result result; + + std::set<Kind> lhs_quals; + std::set<Kind> rhs_quals; + const Type &l = lhs.ResolveQualifiers(lhs_quals); + const Type &r = rhs.ResolveQualifiers(rhs_quals); + if (!lhs_quals.empty() || !rhs_quals.empty()) { + // 3.1 Qualified type difference. + auto lit = lhs_quals.begin(); + auto rit = rhs_quals.begin(); + auto lend = lhs_quals.end(); + auto rend = rhs_quals.end(); + while (lit != lend || rit != rend) { + if (rit == rend || (lit != lend && *lit < *rit)) { + result.AddDiff(QualifiersMessage(*lit, "removed")); + ++lit; + } else if (lit == lend || (rit != rend && *lit > *rit)) { + result.AddDiff(QualifiersMessage(*rit, "added")); + ++rit; + } else { + ++lit; + ++rit; + } + } + const auto comp = Compare(l, r, state); + result.MaybeAddDiff("underlying type", comp); + } else if (l.GetKind() == BTF_KIND_TYPEDEF + || r.GetKind() == BTF_KIND_TYPEDEF) { + // 3.2 Typedef difference. + std::vector<std::string> l_typedefs; + std::vector<std::string> r_typedefs; + const Type &l_ref = l.ResolveTypedef(l_typedefs); + const Type &r_ref = r.ResolveTypedef(r_typedefs); + const auto comp = Compare(l_ref, r_ref, state); + result.MaybeAddDiff("via typedefs", comp); + } else if (typeid(l) != typeid(r)) { + // 4. Incomparable. + result.equals_ = false; + } else { + // 5. Actually compare with dynamic type dispatch. + result = l.Equals(r, state); + } + + // 6. Update result and check for a complete Strongly-Connected Component. + state.provisional.insert({comparison, result.details_}); + auto comparisons = state.scc.Close(handle.value()); + if (!comparisons.empty()) { + // Closed SCC. + // + // Note that result now incorporates every inequality and difference in the + // SCC via the DFS spanning tree. + if (result.equals_) { + // Same. Record equalities. + for (auto &c : comparisons) + state.known_equal.insert(c); + return {true, {}}; + } else { + // Different. Record diffs. + for (auto &c : comparisons) { + auto it = state.provisional.find(c); + state.outcomes.insert(*it); + state.provisional.erase(it); + } + } + } + + // Note that both equals and diff are tentative iff comparison is open. + return {result.equals_, {comparison}}; +} + +Name Void::MakeDescription(NameCache &names) const { + return Name{"void"}; +} + +Name Ptr::MakeDescription(NameCache &names) const { + return GetTypeAtIndex(GetPointeeTypeId()).GetDescription(names).Add( + Side::LEFT, Precedence::POINTER, "*"); +} + +Name Typedef::MakeDescription(NameCache &names) const { + return Name{GetName()}; +} + +Name Qualifier::MakeDescription(NameCache &names) const { + m_assert(false, "should not be called"); // NOLINT + return Name{"qualifier"}; +} + +Name Integer::MakeDescription(NameCache &names) const { + return Name{GetName()}; +} + +Name Array::MakeDescription(NameCache &names) const { + std::ostringstream os; + os << '[' << GetNumberOfElements() << ']'; + return GetTypeAtIndex(GetElementTypeId()).GetDescription(names).Add( + Side::RIGHT, Precedence::ARRAY_FUNCTION, os.str()); +} + +Name StructUnion::MakeDescription(NameCache &names) const { + std::ostringstream os; + os << (GetKind() == BTF_KIND_STRUCT ? "struct" : "union") + << ' ' << (GetName().empty() ? "<anon>" : GetName()); + return Name{os.str()}; +} + +Name Enumeration::MakeDescription(NameCache &names) const { + std::ostringstream os; + os << "enum " << (GetName().empty() ? "<anon>" : GetName()); + if (GetEnums().empty()) + os << "<incomplete>"; + return Name{os.str()}; +} + +Name ForwardDeclaration::MakeDescription(NameCache &names) const { + std::ostringstream os; + os << GetFwdKind() << ' ' << GetName() << "<incomplete>"; + return Name{os.str()}; +} + +Name FunctionPrototype::MakeDescription(NameCache &names) const { + std::ostringstream os; + os << '('; + bool sep = false; + for (const auto &p : GetParameters()) { + if (sep) + os << ", "; + else + sep = true; + const auto &arg_descr = GetTypeAtIndex(p.typeId_).GetDescription(names); + if (p.name_.empty()) + os << arg_descr; + else + os << arg_descr.Add(Side::LEFT, Precedence::ATOMIC, p.name_); + } + os << ')'; + return GetTypeAtIndex(GetReturnTypeId()).GetDescription(names).Add( + Side::RIGHT, Precedence::ARRAY_FUNCTION, os.str()); +} + +Name Variable::MakeDescription(NameCache &names) const { + return GetTypeAtIndex(GetVarTypeId()).GetDescription(names).Add( + Side::LEFT, Precedence::ATOMIC, GetName()); +} + +Name Function::MakeDescription(NameCache &names) const { + return GetTypeAtIndex(GetReferredTypeId()).GetDescription(names).Add( + Side::LEFT, Precedence::ATOMIC, GetName()); +} + +Name DataSection::MakeDescription(NameCache &names) const { + // NOTE: not yet encountered in the wild + return Name{"Unimplemented"}; +} + +Name ElfSymbol::MakeDescription(NameCache &names) const { + return Name{symbol_->get_name()}; +} + +Result Void::Equals(const Type &other, State &state) const { + return {}; +} + +Result Ptr::Equals(const Type &other, State &state) const { + Result result; + const auto &o = other.as<Ptr>(); + + const auto ref_diff = Compare(GetTypeAtIndex(GetPointeeTypeId()), + o.GetTypeAtIndex(o.GetPointeeTypeId()), state); + result.MaybeAddDiff("pointed-to type", ref_diff); + return result; +} + +Result Typedef::Equals(const Type &other, State &state) const { + m_assert(false, "should not be called"); // NOLINT + return {}; +} + +Result Qualifier::Equals(const Type &other, State &state) const { + m_assert(false, "should not be called"); // NOLINT + return {}; +} + +Result Integer::Equals(const Type &other, State &state) const { + Result result; + const auto &o = other.as<Integer>(); + + if (isBool() != o.isBool()) { + result.AddDiff(isBool() ? "the first one is a boolean" + : "the second one is a boolean"); + } + if (isSigned() != o.isSigned()) { + result.AddDiff(isSigned() ? "the first one is signed" + : "the second one is signed"); + } + if (isChar() != o.isChar()) { + result.AddDiff(isChar() ? "the first one is a char" + : "the second one is a char"); + } + result.MaybeAddDiff("offset", GetOffset(), o.GetOffset()); + result.MaybeAddDiff("bit size", GetBitSize(), o.GetBitSize()); + if (GetBitSize() != GetByteSize() * 8 && + o.GetBitSize() != o.GetByteSize() * 8) + result.MaybeAddDiff("byte size", GetByteSize(), o.GetByteSize()); + return result; +} + +Result Array::Equals(const Type &other, State &state) const { + Result result; + const auto &o = other.as<Array>(); + + result.MaybeAddDiff("number of elements", + GetNumberOfElements(), o.GetNumberOfElements()); + const auto index_type_diff = + Compare(GetTypeAtIndex(GetIndexTypeId()), + o.GetTypeAtIndex(o.GetIndexTypeId()), state); + result.MaybeAddDiff("index type", index_type_diff); + const auto element_type_diff = + Compare(GetTypeAtIndex(GetElementTypeId()), + o.GetTypeAtIndex(o.GetElementTypeId()), state); + result.MaybeAddDiff("element type", element_type_diff); + + return result; +} + +Result StructUnion::Equals(const Type &other, State &state) const { + Result result; + const auto &o = other.as<StructUnion>(); + + if (GetKind() != o.GetKind()) { + result.AddDiff(GetKind() == BTF_KIND_STRUCT + ? "changed from struct to union" + : "changed from union to struct"); + } + + result.MaybeAddDiff("byte size", GetByteSize(), o.GetByteSize()); + + const auto &members1 = GetMembers(); + const auto &members2 = o.GetMembers(); + std::set<std::string> visited_members; + for (const auto &m1 : members1) { + visited_members.insert(m1.first); + auto iter = members2.find(m1.first); + if (iter == members2.end()) { + std::ostringstream os; + os << "member " << std::quoted(m1.first) << " of type"; + auto diff = Removed(GetTypeAtIndex(m1.second.typeId_), state); + result.AddDiff(os.str(), diff); + } else { + result.MaybeAddDiff([&](std::ostream &os) { + os << "member " << std::quoted(m1.first) << " offset"; + }, m1.second.offset_, iter->second.offset_); + result.MaybeAddDiff([&](std::ostream &os) { + os << "member " << std::quoted(m1.first) << " bitfield size"; + }, m1.second.bitfieldSize_, iter->second.bitfieldSize_); + const auto sub_diff = + Compare(GetTypeAtIndex(m1.second.typeId_), + o.GetTypeAtIndex(iter->second.typeId_), state); + result.MaybeAddDiff([&](std::ostream &os) { + os << "member " << std::quoted(m1.first) << " type"; + }, sub_diff); + } + } + for (const auto &m2 : members2) { + if (visited_members.find(m2.first) == visited_members.end()) { + std::ostringstream os; + os << "member " << std::quoted(m2.first) << " of type"; + auto diff = Added(o.GetTypeAtIndex(m2.second.typeId_), state); + result.AddDiff(os.str(), diff); + } + } + + return result; +} + +Result Enumeration::Equals(const Type &other, State &state) const { + Result result; + const auto &o = other.as<Enumeration>(); + + result.MaybeAddDiff("byte size", GetByteSize(), o.GetByteSize()); + + const auto &enums1 = GetEnums(); + const auto &enums2 = o.GetEnums(); + std::set<std::string> visited_enums; + for (const auto &e1 : enums1) { + visited_enums.insert(e1.first); + auto iter = enums2.find(e1.first); + if (iter == enums2.end()) { + std::ostringstream os; + os << "enumerator " << std::quoted(e1.first) + << " (" << e1.second << ") was removed"; + result.AddDiff(os.str()); + } else { + result.MaybeAddDiff([&](std::ostream &os) { + os << "enumerator " << std::quoted(e1.first) << " value"; + }, e1.second, iter->second); + } + } + for (const auto &e2 : enums2) { + if (visited_enums.find(e2.first) == visited_enums.end()) { + std::ostringstream os; + os << "enumerator " << std::quoted(e2.first) + << " (" << e2.second << ") was added"; + result.AddDiff(os.str()); + } + } + + return result; +} + +Result ForwardDeclaration::Equals(const Type &other, State &state) const { + Result result; + const auto &o = other.as<ForwardDeclaration>(); + + result.MaybeAddDiff("kind", GetFwdKind(), o.GetFwdKind()); + + return result; +} + +Result Function::Equals(const Type &other, State &state) const { + Result result; + const auto &o = other.as<Function>(); + + result.MaybeAddDiff("linkage", GetLinkage(), o.GetLinkage()); + const auto func_proto_diff = + Compare(GetTypeAtIndex(GetReferredTypeId()), + o.GetTypeAtIndex(o.GetReferredTypeId()), state); + result.MaybeAddDiff("type", func_proto_diff); + + return result; +} + +Result FunctionPrototype::Equals(const Type &other, State &state) const { + Result result; + const auto &o = other.as<FunctionPrototype>(); + + const auto return_type_diff = + Compare(GetTypeAtIndex(GetReturnTypeId()), + o.GetTypeAtIndex(o.GetReturnTypeId()), state); + result.MaybeAddDiff("return type", return_type_diff); + + const auto ¶meters1 = GetParameters(); + const auto ¶meters2 = o.GetParameters(); + size_t min = std::min(parameters1.size(), parameters2.size()); + for (size_t i = 0; i < min; ++i) { + const auto &p1 = parameters1.at(i); + const auto &p2 = parameters2.at(i); + const auto sub_diff = Compare(GetTypeAtIndex(p1.typeId_), + o.GetTypeAtIndex(p2.typeId_), state); + result.MaybeAddDiff([&](std::ostream &os) { + os << "parameter " << i + 1; + const auto &n1 = p1.name_; + const auto &n2 = p2.name_; + if (n1 == n2 && !n1.empty()) { + os << " (" << std::quoted(n1) << ")"; + } else if (n1 != n2) { + os << " ("; + if (!n1.empty()) os << "was " << std::quoted(n1); + if (!n1.empty() && !n2.empty()) os << ", "; + if (!n2.empty()) os << "now " << std::quoted(n2); + os << ")"; + } + os << " type"; + }, sub_diff); + } + + bool added = parameters1.size() < parameters2.size(); + const auto ¶meters = added ? parameters2 : parameters1; + for (size_t i = min; i < parameters.size(); ++i) { + const auto ¶meter = parameters.at(i); + std::ostringstream os; + os << "parameter " << i + 1; + if (!parameter.name_.empty()) + os << " (" << std::quoted(parameter.name_) << ")"; + os << " of type"; + const auto ¶meter_type = GetTypeAtIndex(parameter.typeId_); + auto diff = added ? Added(parameter_type, state) + : Removed(parameter_type, state); + result.AddDiff(os.str(), diff); + } + + return result; +} + +// NOTE: not yet encountered in the wild +Result Variable::Equals(const Type &other, State &state) const { + Result result; + const auto &o = other.as<Variable>(); + + result.MaybeAddDiff("linkage", GetLinkage(), o.GetLinkage()); + const auto var_diff = Compare(GetTypeAtIndex(GetVarTypeId()), + o.GetTypeAtIndex(o.GetVarTypeId()), state); + result.MaybeAddDiff("type", var_diff); + + return result; +} + +Result DataSection::Equals(const Type &other, State &state) const { + Result result; + result.AddDiff("Unimplemented"); + + // NOTE: not yet encountered in the wild + m_assert(false, "Unimplemented\n"); // NOLINT + + return result; +} + +Result ElfSymbol::Equals(const Type &other, State &state) const { + Result result; + const auto &o = other.as<ElfSymbol>(); + // TODO: compare ELF symbol attributes + const auto type_diff = Compare(GetTypeAtIndex(type_id_), + o.GetTypeAtIndex(o.type_id_), state); + result.MaybeAddDiff("type", type_diff); + return result; +} + +const Type &Type::ResolveQualifiers(std::set<Kind> &qualifiers) const { + if (kind_ == BTF_KIND_ARRAY || kind_ == BTF_KIND_FUNC_PROTO) { + // There should be no qualifiers here. + qualifiers.clear(); + } + return *this; +} + +const Type &Qualifier::ResolveQualifiers( + std::set<Kind> &qualifiers) const { + qualifiers.insert(GetKind()); + return GetTypeAtIndex(GetQualifiedTypeId()).ResolveQualifiers(qualifiers); +} + +const Type &Type::ResolveTypedef( + std::vector<std::string> &typedefs) const { + return *this; +} + +const Type &Typedef::ResolveTypedef( + std::vector<std::string> &typedefs) const { + typedefs.push_back(GetName()); + return GetTypeAtIndex(GetReferredTypeId()).ResolveTypedef(typedefs); +} + +static constexpr std::string_view ANON{"(anon)"}; + +std::ostream &operator<<(std::ostream &os, const Ptr &bp) { + os << kRawKindNames[bp.GetKind()] + << " '" << ANON << "'" + << " type_id=" << bp.GetPointeeTypeId() + << '\n'; + return os; +} + +std::ostream &operator<<(std::ostream &os, const Typedef &bp) { + os << kRawKindNames[bp.GetKind()] + << " '" << bp.GetName() << "'" + << " type_id=" << bp.GetReferredTypeId() + << '\n'; + return os; +} + +std::ostream &operator<<(std::ostream &os, const Qualifier &bp) { + os << kRawKindNames[bp.GetKind()] + << " '" << ANON << "'" + << " type_id=" << bp.GetQualifiedTypeId() + << '\n'; + return os; +} + +std::ostream &operator<<(std::ostream &os, const Integer &bi) { + os << kRawKindNames[bi.GetKind()] + << " '" << bi.GetName() << "'" + << " size=" << bi.GetByteSize() + << " bits_offset=" << bi.GetOffset() + << " nr_bits=" << bi.GetBitSize() + << " bool=" << bi.isBool() + << " char=" << bi.isChar() + << " signed=" << bi.isSigned() + << '\n'; + return os; +} + +std::ostream &operator<<(std::ostream &os, const Array &ba) { + os << kRawKindNames[ba.GetKind()] + << " '" << ANON << "'" + << " type_id=" << ba.GetElementTypeId() + << " index_type_id=" << ba.GetIndexTypeId() + << " nr_elems=" << ba.GetNumberOfElements() + << '\n'; + return os; +} + +std::ostream &operator<<(std::ostream &os, const StructUnion &bsu) { + const auto &name = bsu.GetName(); + os << kRawKindNames[bsu.GetKind()] + << " '" << (name.empty() ? ANON : name) << "'" + << " size=" << bsu.GetByteSize() + << " vlen=" << bsu.GetMembers().size() << '\n'; + for (const auto &member : bsu.GetMembers()) { + os << "\t'" << member.first << '\'' + << " type_id=" << member.second.typeId_ + << " bits_offset=" << member.second.offset_; + if (member.second.bitfieldSize_) + os << " bitfield_size=" << member.second.bitfieldSize_; + os << '\n'; + } + return os; +} + +std::ostream &operator<<(std::ostream &os, const Enumeration &be) { + const auto &name = be.GetName(); + os << kRawKindNames[be.GetKind()] + << " '" << (name.empty() ? ANON : name) << "'" + << " size=" << be.GetByteSize() + << " vlen=" << be.GetEnums().size() + << '\n'; + for (const auto &e : be.GetEnums()) { + os << "\t'" << e.first << "' val=" << e.second << '\n'; + } + return os; +} + +std::ostream &operator<<(std::ostream &os, const ForwardDeclaration &bfd) { + os << kRawKindNames[bfd.GetKind()] + << " '" << bfd.GetName() << "'" + << " fwd_kind=" << bfd.GetFwdKind() + << '\n'; + return os; +} + +std::ostream &operator<<(std::ostream &os, const Function &bf) { + os << kRawKindNames[bf.GetKind()] + << " '" << bf.GetName() << "'" + << " type_id=" << bf.GetReferredTypeId() + << " linkage=" << bf.GetLinkage() + << '\n'; + return os; +} + +std::ostream &operator<<(std::ostream &os, const FunctionPrototype &bfp) { + os << kRawKindNames[bfp.GetKind()] + << " '" << ANON << "'" + << " ret_type_id=" << bfp.GetReturnTypeId() + << " vlen=" << bfp.GetParameters().size() + << '\n'; + for (const auto ¶m : bfp.GetParameters()) { + os << "\t'" << (param.name_.empty() ? ANON : param.name_) + << "' type_id=" << param.typeId_ << '\n'; + } + return os; +} + +std::ostream &operator<<(std::ostream &os, const Variable &bv) { + // NOTE: The odd comma is to match bpftool dump. + os << kRawKindNames[bv.GetKind()] + << " type_id=" << bv.GetVarTypeId() + << ", linkage=" << bv.GetLinkage() + << '\n'; + return os; +} + +std::ostream &operator<<(std::ostream &os, const DataSection &bds) { + os << kRawKindNames[bds.GetKind()] + << " size=" << bds.GetByteSize() + << '\n'; + for (const auto &secinfo : bds.GetSecinfos()) { + os << "\ttype_id=" << secinfo.typeId_ + << " offset=" << secinfo.offset_ + << " size=" << secinfo.bytesize_ << '\n'; + } + return os; +} + +std::ostream &operator<<(std::ostream &os, const ElfSymbol &bes) { + os << kRawKindNames[bes.GetKind()]; + // TODO: report ELF symbol attributes + os << " type=" << bes.GetTypeId() + << '\n'; + return os; +} + +std::ostream &operator<<(std::ostream &os, ForwardDeclarationKind kind) { + switch (kind) { + case ForwardDeclarationKind::STRUCT: + os << "struct"; + break; + case ForwardDeclarationKind::UNION: + os << "union"; + break; + } + return os; +} + +std::ostream &operator<<(std::ostream &os, Variable::Linkage linkage) { + auto ix = static_cast<size_t>(linkage); + return os << (ix < kVarLinkage.size() ? kVarLinkage[ix] : "(unknown)"); +} + +std::ostream &operator<<(std::ostream &os, Function::Linkage linkage) { + auto ix = static_cast<size_t>(linkage); + return os << (ix < kFunLinkage.size() ? kFunLinkage[ix] : "(unknown)"); +} + +Structs::Structs(const char *start, + std::unique_ptr<abigail::ir::environment> env, + const abigail::symtab_reader::symtab_sptr tab, + const bool verbose) + : env_(std::move(env)), + tab_(tab), + verbose_(verbose) { + header_ = reinterpret_cast<const btf_header *>(start); + m_assert(header_->magic == 0xEB9F, "Magic field must be 0xEB9F for BTF"); + + type_section_ = reinterpret_cast<const btf_type *>(start + header_->hdr_len + + header_->type_off); + str_section_ = start + header_->hdr_len + header_->str_off; + + // every btf_type struct in the type section has an implicit type id. + // type id 0 is reserved for void type, so it is set to a Void here. + // The type section is parsed sequentially and type id is assigned to each + // recognized type starting from id 1. + types_.push_back(std::make_unique<Void>(types_, 0, 0)); + + if (verbose_) { + PrintHeader(); + } + BuildTypes(); + if (verbose_) { + PrintStringSection(); + } + + // NOTE: a whole bunch of Linux kernel symbols appear with duplicate (but not + // necessarily identical) BTF type information + // + // TODO: find a better way of resolving this + bad_prefix_1_ = "__arm64_sys_"; + bad_prefix_2_ = "__arm64_compat_sys_"; + bad_names_ = { + "arch_prctl_spec_ctrl_get", + "arch_prctl_spec_ctrl_set", + "ioremap_cache", + "kvm_arch_set_irq_inatomic", + "module_frob_arch_sections", + "vsnprintf" + }; +} + +void Structs::PrintHeader() { + std::cout << "BTF header:\n" + << "\tmagic " << header_->magic + << ", version " << static_cast<int>(header_->version) + << ", flags " << static_cast<int>(header_->flags) + << ", hdr_len " << header_->hdr_len << "\n" + << "\ttype_off " << header_->type_off + << ", type_len " << header_->type_len << "\n" + << "\tstr_off " << header_->str_off + << ", str_len " << header_->str_len << "\n"; +} + +// vlen: vector length, the number of struct/union members +std::map<std::string, Member> Structs::BuildMembers( + bool kflag, const btf_member *members, size_t vlen) { + std::map<std::string, Member> result; + int anonymous = 0; + for (size_t i = 0; i < vlen; ++i) { + const auto raw_offset = members[i].offset; + Member member{ + .typeId_ = members[i].type, + .offset_ = kflag ? BTF_MEMBER_BIT_OFFSET(raw_offset) : raw_offset, + .bitfieldSize_ = kflag ? BTF_MEMBER_BITFIELD_SIZE(raw_offset) : 0}; + std::string name = std::string(GetName(members[i].name_off)); + if (name.empty()) { + name = "anon member #" + std::to_string(anonymous); + ++anonymous; + } + result.emplace(name, member); + } + return result; +} + +// vlen: vector length, the number of enum values +std::map<std::string, int> Structs::BuildEnums(const struct btf_enum *enums, + size_t vlen) { + std::map<std::string, int> result; + for (size_t i = 0; i < vlen; ++i) { + result.emplace(std::string(GetName(enums[i].name_off)), enums[i].val); + } + return result; +} + +// vlen: vector length, the number of parameters +std::vector<Parameter> Structs::BuildParams(const struct btf_param *params, + size_t vlen) { + std::vector<Parameter> result; + result.reserve(vlen); + for (size_t i = 0; i < vlen; ++i) { + Parameter parameter{ + .name_ = std::string(GetName(params[i].name_off)), + .typeId_ = params[i].type}; + result.push_back(parameter); + } + return result; +} + +// vlen: vector length, the number of variables +std::vector<Secinfo> Structs::BuildDatasec(const btf_type *type, + size_t vlen) { + std::vector<Secinfo> result; + result.reserve(vlen); + const auto *secinfos = reinterpret_cast<const btf_var_secinfo *>(type + 1); + for (size_t i = 0; i < vlen; ++i) { + Secinfo secinfo{.typeId_ = secinfos[i].type, + .offset_ = secinfos[i].offset, + .bytesize_ = secinfos[i].size}; + result.push_back(secinfo); + } + return result; +} + +void Structs::BuildTypes() { + m_assert(!(header_->type_off & (sizeof(uint32_t) - 1)), "Unaligned type_off"); + if (header_->type_len == 0) { + std::cerr << "No types found"; + return; + } + if (verbose_) { + std::cout << "Type section:\n"; + } + + const char *curr = reinterpret_cast<const char *>(type_section_); + const char *end = curr + header_->type_len; + uint32_t index = 1; + while (curr < end) { + const btf_type *t = reinterpret_cast<const btf_type *>(curr); + int type_size = BuildOneType(t, index); + m_assert(type_size > 0, "Could not identify BTF type"); + curr += type_size; + ++index; + } + + BuildElfSymbols(); +} + +int Structs::BuildOneType(const btf_type *t, uint32_t index) { + const auto kind = BTF_INFO_KIND(t->info); + const auto vlen = BTF_INFO_VLEN(t->info); + // Data following the btf_type struct. + const void *data = reinterpret_cast<const void *>(t + 1); + m_assert(kind >= 0 && kind < NR_BTF_KINDS, "Unknown BTF kind"); + + if (verbose_) std::cout << '[' << index << "] "; + int type_size = sizeof(struct btf_type); + switch (kind) { + case BTF_KIND_INT: { + const auto bits = *reinterpret_cast<const uint32_t *>(data); + types_.push_back(std::make_unique<Integer>( + types_, index, GetName(t->name_off), kind, + BTF_INT_ENCODING(bits), BTF_INT_OFFSET(bits), BTF_INT_BITS(bits), + t->size)); + if (verbose_) { + std::cout << types_.back()->as<Integer>(); + } + type_size += sizeof(uint32_t); + break; + } + case BTF_KIND_PTR: { + types_.push_back(std::make_unique<Ptr>(types_, index, kind, t->type)); + if (verbose_) { + std::cout << types_.back()->as<Ptr>(); + } + break; + } + case BTF_KIND_TYPEDEF: { + types_.push_back(std::make_unique<Typedef>( + types_, index, GetName(t->name_off), kind, t->type)); + if (verbose_) { + std::cout << types_.back()->as<Typedef>(); + } + break; + } + case BTF_KIND_VOLATILE: + case BTF_KIND_CONST: + case BTF_KIND_RESTRICT: { + types_.push_back(std::make_unique<Qualifier>( + types_, index, kind, t->type)); + if (verbose_) { + std::cout << types_.back()->as<Qualifier>(); + } + break; + } + case BTF_KIND_ARRAY: { + const auto *array = reinterpret_cast<const struct btf_array *>(data); + types_.push_back(std::make_unique<Array>( + types_, index, kind, array->type, array->index_type, array->nelems)); + if (verbose_) { + std::cout << types_.back()->as<Array>(); + } + type_size += sizeof(struct btf_array); + break; + } + case BTF_KIND_STRUCT: + case BTF_KIND_UNION: { + const bool kflag = BTF_INFO_KFLAG(t->info); + const auto *btf_members = reinterpret_cast<const btf_member *>(data); + const auto members = BuildMembers(kflag, btf_members, vlen); + types_.push_back(std::make_unique<StructUnion>( + types_, index, GetName(t->name_off), kind, t->size, members)); + if (verbose_) { + std::cout << types_.back()->as<StructUnion>(); + } + type_size += vlen * sizeof(struct btf_member); + break; + } + case BTF_KIND_ENUM: { + const auto *enums = reinterpret_cast<const struct btf_enum *>(data); + std::map<std::string, int> enumerators = BuildEnums(enums, vlen); + types_.push_back(std::make_unique<Enumeration>( + types_, index, GetName(t->name_off), kind, + t->size, enumerators)); + if (verbose_) { + std::cout << types_.back()->as<Enumeration>(); + } + type_size += vlen * sizeof(struct btf_enum); + break; + } + case BTF_KIND_FWD: { + const bool kflag = BTF_INFO_KFLAG(t->info); + types_.push_back(std::make_unique<ForwardDeclaration>( + types_, index, GetName(t->name_off), kind, kflag)); + if (verbose_) { + std::cout << types_.back()->as<ForwardDeclaration>(); + } + break; + } + case BTF_KIND_FUNC: { + const auto name = GetName(t->name_off); + types_.push_back(std::make_unique<Function>( + types_, index, name, kind, t->type, + Function::Linkage(vlen))); + if (verbose_) { + std::cout << types_.back()->as<Function>(); + } + bool inserted = btf_symbol_types_.insert({name, t->type}).second; + if (!inserted) { + // NOTE: duplicate BTF symbols could be considered a bug in pahole + // + // TODO: remove these checks once resolved + bool known = !name.compare(0, bad_prefix_1_.size(), bad_prefix_1_) || + !name.compare(0, bad_prefix_2_.size(), bad_prefix_2_) || + std::find(bad_names_.begin(), bad_names_.end(), name) != + bad_names_.end(); + m_assert(known, "Insertion failed, duplicate found in symbol map"); + (void)known; + } + btf_symbols_.insert({name, types_.back().get()}); + break; + } + case BTF_KIND_FUNC_PROTO: { + const auto *params = reinterpret_cast<const btf_param *>(data); + std::vector<Parameter> parameters = BuildParams(params, vlen); + types_.push_back(std::make_unique<FunctionPrototype>( + types_, index, kind, t->type, parameters)); + if (verbose_) { + std::cout << types_.back()->as<FunctionPrototype>(); + } + type_size += vlen * sizeof(struct btf_param); + break; + } + case BTF_KIND_VAR: { + // NOTE: not yet encountered in the wild + const auto *variable = reinterpret_cast<const struct btf_var *>(data); + const auto name = GetName(t->name_off); + types_.push_back(std::make_unique<Variable>( + types_, index, name, kind, t->type, + Variable::Linkage(variable->linkage))); + if (verbose_) { + std::cout << types_.back()->as<Variable>(); + } + + bool inserted = btf_symbol_types_.insert({name, t->type}).second; + m_assert(inserted, "Insertion failed, duplicate found in symbol map"); + (void)inserted; + btf_symbols_.insert({name, types_.back().get()}); + + type_size += sizeof(struct btf_var); + break; + } + case BTF_KIND_DATASEC: { + std::vector<Secinfo> secinfos = BuildDatasec(t, vlen); + types_.push_back(std::make_unique<DataSection>( + types_, index, kind, t->size, secinfos)); + if (verbose_) { + std::cout << types_.back()->as<DataSection>(); + } + type_size += vlen * sizeof(struct btf_var_secinfo); + } + } + return type_size; +} + +std::string Structs::GetName(uint32_t name_off) { + m_assert(name_off < header_->str_len, + "The name offset exceeds the section length"); + const char *section_end = str_section_ + header_->str_len; + const char *name_begin = str_section_ + name_off; + const char *name_end = std::find(name_begin, section_end, '\0'); + m_assert(name_end < section_end, + "The name continues past the string section limit"); + return {name_begin, static_cast<size_t>(name_end - name_begin)}; +} + +void Structs::PrintStringSection() { + std::cout << "String section:\n"; + const char *curr = str_section_; + const char *limit = str_section_ + header_->str_len; + while (curr < limit) { + const char *pos = std::find(curr, limit, '\0'); + m_assert(pos < limit, "Error reading the string section"); + std::cout << ' ' << curr; + curr = pos + 1; + } + std::cout << '\n'; +} + +void Structs::BuildElfSymbols() { + const auto filter = [&]() { + auto filter = tab_->make_filter(); + filter.set_public_symbols(); + return filter; + }(); + for (const auto &symbol : + abigail::symtab_reader::filtered_symtab(*tab_, filter)) { + const auto &symbol_name = symbol->get_name(); + const auto &main_symbol_name = symbol->get_main_symbol()->get_name(); + auto it = btf_symbol_types_.find(main_symbol_name); + if (it == btf_symbol_types_.end()) { + // missing BTF information is tracked explicitly + std::cerr << "ELF symbol " << std::quoted(symbol_name); + if (symbol_name != main_symbol_name) + std::cerr << " (aliased to " << std::quoted(main_symbol_name) << ')'; + std::cerr << " BTF info missing\n"; + types_.push_back(nullptr); + } else { + uint32_t type_id = it->second; + types_.push_back(std::make_unique<ElfSymbol>(types_, symbol, type_id)); + } + elf_symbols_.emplace(symbol_name, types_.back().get()); + } +} + +class ElfHandle { + public: + ElfHandle(const std::string &path) : dwfl_(nullptr, dwfl_end) { + string name; + tools_utils::base_name(path, name); + + elf_version(EV_CURRENT); + + dwfl_ = std::unique_ptr<Dwfl, decltype(&dwfl_end)>( + dwfl_begin(&offline_callbacks_), dwfl_end); + auto dwfl_module = dwfl_report_offline(dwfl_.get(), name.c_str(), + path.c_str(), -1); + GElf_Addr bias; + elf_handle_ = dwfl_module_getelf(dwfl_module, &bias); + } + + // Conversion operator to act as a drop-in replacement for Elf* + operator Elf *() const { return elf_handle_; } + + Elf *get() const { return elf_handle_; } + + private: + // Dwfl owns all our data, hence only keep track of this + std::unique_ptr<Dwfl, decltype(&dwfl_end)> dwfl_; + Elf *elf_handle_; + + Dwfl_Callbacks offline_callbacks_; +}; + +Structs ReadFile(const std::string &path, bool verbose) { + using abigail::symtab_reader::symtab; + + ElfHandle elf(path); + m_assert(elf.get() != nullptr, "Could not get elf handle from file."); + + Elf_Scn *btf_section = + abigail::elf_helpers::find_section(elf, ".BTF", SHT_PROGBITS); + m_assert(btf_section != nullptr, + "The given file does not have a BTF section"); + Elf_Data *elf_data = elf_rawdata(btf_section, 0); + m_assert(elf_data != nullptr, "The BTF section is invalid"); + const char *btf_start = static_cast<char *>(elf_data->d_buf); + + auto env = std::make_unique<abigail::ir::environment>(); + auto tab = symtab::load(elf, env.get()); + + return Structs(btf_start, std::move(env), std::move(tab), verbose); +} + +} // end namespace btf +} // end namespace abigail -- 2.32.0.288.g62a8d224e6-goog ^ permalink raw reply [flat|nested] 14+ messages in thread
* [PATCH v2 5/6] BTF: add btfinfo and btfdiff tools 2021-06-22 10:33 ` [PATCH v2 0/6] BTF ABI Giuliano Procida ` (3 preceding siblings ...) 2021-06-22 10:33 ` [PATCH v2 4/6] BTF: add core functionality Giuliano Procida @ 2021-06-22 10:33 ` Giuliano Procida 2021-06-22 10:33 ` [PATCH v2 6/6] BTF: clang-format all the new source files Giuliano Procida 5 siblings, 0 replies; 14+ messages in thread From: Giuliano Procida @ 2021-06-22 10:33 UTC (permalink / raw) To: libabigail; +Cc: dodji, kernel-team, gprocida, maennich, Maria Teguiani This commit adds BTF command line tools. They are fairly thin wrappers around the core BTF functionality. The files are almost a straight copy of the originals. Changes: - Files renamed and #includes updated. * tools/Makefile.am: Compile BTF tools, conditional on C++17 and <linux/btf.h>. * tools/btfdiff.cc: New utility that compares BTF information. * tools/btfinfo.cc: New utility that dumps BTF information. Co-authored-by: Maria Teguiani <teguiani@google.com> Signed-off-by: Giuliano Procida <gprocida@google.com> --- tools/Makefile.am | 14 ++++++++++ tools/btfdiff.cc | 68 +++++++++++++++++++++++++++++++++++++++++++++++ tools/btfinfo.cc | 19 +++++++++++++ 3 files changed, 101 insertions(+) create mode 100644 tools/btfdiff.cc create mode 100644 tools/btfinfo.cc diff --git a/tools/Makefile.am b/tools/Makefile.am index 648a71b5..bd310c18 100644 --- a/tools/Makefile.am +++ b/tools/Makefile.am @@ -9,6 +9,12 @@ else noinst_SCRIPTS = fedabipkgdiff endif +if ENABLE_CXX17 +if HAVE_BTF + bin_PROGRAMS += btfinfo btfdiff +endif +endif + noinst_PROGRAMS = abisym abinilint abidiff_SOURCES = abidiff.cc @@ -45,6 +51,14 @@ kmidiffdir = $(bindir) kmidiff_LDADD = $(abs_top_builddir)/src/libabigail.la kmidiff_LDFLAGS = -pthread +btfinfo_SOURCES = btfinfo.cc +btfinfodir = $(bindir) +btfinfo_LDADD = ../src/libabigail.la + +btfdiff_SOURCES = btfdiff.cc +btfdiffdir = $(bindir) +btfdiff_LDADD = ../src/libabigail.la + AM_CXXFLAGS = \ $(VISIBILITY_FLAGS) -I$(abs_top_srcdir)/include \ -I$(abs_top_srcdir)/tools -fPIC diff --git a/tools/btfdiff.cc b/tools/btfdiff.cc new file mode 100644 index 00000000..0649821d --- /dev/null +++ b/tools/btfdiff.cc @@ -0,0 +1,68 @@ +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// -*- mode: C++ -*- +// +// Copyright (C) 2020-2021 Google, Inc. +// +// Author: Maria Teguiani +// Author: Giuliano Procida + +#include <getopt.h> + +#include <cstring> +#include <iomanip> +#include <iostream> + +#include "abg-btf.h" + +const int kAbiChange = 4; + +int main(int argc, char *argv[]) { + bool use_elf_symbols = true; + static option opts[] = { + { "symbols", required_argument, nullptr, 's' }, + { nullptr, 0, nullptr, 0 }, + }; + auto usage = [&]() { + std::cerr << "usage: " << argv[0] + << " [-s|--symbols type] file1 file2\n" + << " where type is elf (the default) or btf\n"; + return 1; + }; + auto bad_arg = [&](int ix) { + std::cerr << argv[0] << ": option '--" << opts[ix].name + << "' unrecognized argument '" << optarg << "'\n"; + return usage(); + }; + while (true) { + int ix; + int c = getopt_long(argc, argv, "s:", opts, &ix); + if (c == -1) + break; + switch (c) { + case 's': + if (!strcmp(optarg, "btf")) + use_elf_symbols = false; + else if (!strcmp(optarg, "elf")) + use_elf_symbols = true; + else + return bad_arg(ix); + break; + default: + return usage(); + } + } + if (optind + 2 != argc) + return usage(); + + const auto structs1 = abigail::btf::ReadFile(argv[optind++]); + const auto structs2 = abigail::btf::ReadFile(argv[optind++]); + const auto &map1 = structs1.GetSymbols(use_elf_symbols); + const auto &map2 = structs2.GetSymbols(use_elf_symbols); + abigail::btf::Outcomes outcomes; + auto result = abigail::btf::Type::CompareSymbols(map1, map2, outcomes); + abigail::btf::NameCache names; + abigail::btf::Seen seen; + abigail::btf::Print(result.details_, outcomes, seen, names, std::cout); + + return result.equals_ ? 0 : kAbiChange; +} diff --git a/tools/btfinfo.cc b/tools/btfinfo.cc new file mode 100644 index 00000000..dbda7945 --- /dev/null +++ b/tools/btfinfo.cc @@ -0,0 +1,19 @@ +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// -*- mode: C++ -*- +// +// Copyright (C) 2020 Google, Inc. +// +// Author: Maria Teguiani + +#include "abg-btf.h" + +int main(int argc, const char *argv[]) { + if (argc != 2) { + std::cerr << "Please specify the path to a BTF file."; + return 1; + } + + (void) abigail::btf::ReadFile(argv[1], /* verbose = */ true); + + return 0; +} -- 2.32.0.288.g62a8d224e6-goog ^ permalink raw reply [flat|nested] 14+ messages in thread
* [PATCH v2 6/6] BTF: clang-format all the new source files 2021-06-22 10:33 ` [PATCH v2 0/6] BTF ABI Giuliano Procida ` (4 preceding siblings ...) 2021-06-22 10:33 ` [PATCH v2 5/6] BTF: add btfinfo and btfdiff tools Giuliano Procida @ 2021-06-22 10:33 ` Giuliano Procida 5 siblings, 0 replies; 14+ messages in thread From: Giuliano Procida @ 2021-06-22 10:33 UTC (permalink / raw) To: libabigail; +Cc: dodji, kernel-team, gprocida, maennich This is to bring them closer to the libabigail coding style. * include/abg-btf.h: Reformatted with clang-format. * include/abg-scc.h: Reformatted with clang-format. * src/abg-btf.cc: Reformatted with clang-format. * tests/test-scc.cc: Reformatted with clang-format. * tools/btfdiff.cc: Reformatted with clang-format. * tools/btfinfo.cc: Reformatted with clang-format. Signed-off-by: Giuliano Procida <gprocida@google.com> --- include/abg-btf.h | 1082 ++++++++++++++++--------- include/abg-scc.h | 68 +- src/abg-btf.cc | 1905 ++++++++++++++++++++++++++------------------- tests/test-scc.cc | 203 +++-- tools/btfdiff.cc | 55 +- tools/btfinfo.cc | 13 +- 6 files changed, 2012 insertions(+), 1314 deletions(-) diff --git a/include/abg-btf.h b/include/abg-btf.h index f7243fa3..7cb74246 100644 --- a/include/abg-btf.h +++ b/include/abg-btf.h @@ -26,16 +26,19 @@ #include "abg-ir.h" #include "abg-scc.h" -namespace abigail { -namespace btf { +namespace abigail +{ +namespace btf +{ -#define m_assert(expr, msg) assert(((void)(msg), (expr))) +#define m_assert(expr, msg) assert(((void) (msg), (expr))) using Kind = uint32_t; // A Member refers to a data element of a struct or union, used in the context // of StructUnion -struct Member { +struct Member +{ uint32_t typeId_; uint32_t offset_; uint32_t bitfieldSize_; @@ -43,125 +46,178 @@ struct Member { // A Parameter refers to a variable declared in the function declaration, used // in the context of Function -struct Parameter { +struct Parameter +{ std::string name_; uint32_t typeId_; }; -struct Secinfo { +struct Secinfo +{ uint32_t typeId_; uint32_t offset_; uint32_t bytesize_; }; -enum class ForwardDeclarationKind { STRUCT, UNION }; +enum class ForwardDeclarationKind +{ + STRUCT, + UNION +}; -std::ostream &operator<<(std::ostream &os, ForwardDeclarationKind kind); +std::ostream& +operator<<(std::ostream& os, ForwardDeclarationKind kind); class Type; -using Comparison = std::pair<const Type *, const Type *>; - -enum class Precedence { NIL, POINTER, ARRAY_FUNCTION, ATOMIC }; -enum class Side { LEFT, RIGHT }; +using Comparison = std::pair<const Type*, const Type*>; -class Name { - public: - explicit Name(const std::string &name) - : left_(name), precedence_(Precedence::NIL), right_() {} - Name(const std::string &left, Precedence precedence, const std::string &right) - : left_(left), precedence_(precedence), right_(right) {} - Name Add(Side side, Precedence precedence, const std::string &text) const; - Name Qualify(const std::set<Kind> &qualifiers) const; - std::ostream &Print(std::ostream &os) const; +enum class Precedence +{ + NIL, + POINTER, + ARRAY_FUNCTION, + ATOMIC +}; +enum class Side +{ + LEFT, + RIGHT +}; - private: +class Name +{ +public: + explicit Name(const std::string& name) + : left_(name), precedence_(Precedence::NIL), right_() + { + } + Name(const std::string& left, + Precedence precedence, + const std::string& right) + : left_(left), precedence_(precedence), right_(right) + { + } + Name + Add(Side side, Precedence precedence, const std::string& text) const; + Name + Qualify(const std::set<Kind>& qualifiers) const; + std::ostream& + Print(std::ostream& os) const; + +private: std::string left_; Precedence precedence_; std::string right_; }; -std::ostream &operator<<(std::ostream &os, const Name &name); +std::ostream& +operator<<(std::ostream& os, const Name& name); -using NameCache = std::unordered_map<const Type *, Name>; +using NameCache = std::unordered_map<const Type*, Name>; -struct DiffDetail { - DiffDetail(const std::string &text, const std::optional<Comparison> &edge) - : text_(text), edge_(edge) {} +struct DiffDetail +{ + DiffDetail(const std::string& text, const std::optional<Comparison>& edge) + : text_(text), edge_(edge) + { + } std::string text_; std::optional<Comparison> edge_; }; using Diff = std::vector<DiffDetail>; -struct Result { - void AddDiff(const std::string &text) { +struct Result +{ + void + AddDiff(const std::string& text) + { equals_ = false; details_.emplace_back(text, std::optional<Comparison>()); } - void AddDiff(const std::string &text, Comparison comparison) { + void + AddDiff(const std::string& text, Comparison comparison) + { equals_ = false; details_.emplace_back(text, comparison); } - void MaybeAddDiff(const std::string &text, - const std::pair<bool, std::optional<Comparison>> &p) { + void + MaybeAddDiff(const std::string& text, + const std::pair<bool, std::optional<Comparison>>& p) + { equals_ &= p.first; - const auto &diff = p.second; + const auto& diff = p.second; if (diff) details_.emplace_back(text, diff); } // Maximally powerful lazy version, takes a function that outputs an "edge" // diff description, to be used only when a diff is present. - void MaybeAddDiff(std::function<void(std::ostream &)> text, - const std::pair<bool, std::optional<Comparison>> &p) { + void + MaybeAddDiff(std::function<void(std::ostream&)> text, + const std::pair<bool, std::optional<Comparison>>& p) + { equals_ &= p.first; - const auto &diff = p.second; - if (diff) { - std::ostringstream os; - text(os); - details_.emplace_back(os.str(), diff); - } + const auto& diff = p.second; + if (diff) + { + std::ostringstream os; + text(os); + details_.emplace_back(os.str(), diff); + } } - template<typename T> void MaybeAddDiff( - const std::string &text, const T &before, const T &after) { - if (before != after) { - equals_ = false; - std::ostringstream os; - os << text << " changed from " << before << " to " << after; - AddDiff(os.str()); - } + template <typename T> + void + MaybeAddDiff(const std::string& text, const T& before, const T& after) + { + if (before != after) + { + equals_ = false; + std::ostringstream os; + os << text << " changed from " << before << " to " << after; + AddDiff(os.str()); + } } // Lazy version. - template<typename T> void MaybeAddDiff( - std::function<void(std::ostream &)> text, - const T &before, const T &after) { - if (before != after) { - equals_ = false; - std::ostringstream os; - text(os); - os << " changed from " << before << " to " << after; - AddDiff(os.str()); - } + template <typename T> + void + MaybeAddDiff(std::function<void(std::ostream&)> text, + const T& before, + const T& after) + { + if (before != after) + { + equals_ = false; + std::ostringstream os; + text(os); + os << " changed from " << before << " to " << after; + AddDiff(os.str()); + } } bool equals_ = true; Diff details_; }; -struct HashComparison { - size_t operator()(const Comparison &comparison) const { +struct HashComparison +{ + size_t + operator()(const Comparison& comparison) const + { size_t seed = 0; - std::hash<const Type *> h; + std::hash<const Type*> h; combine_hash(seed, h(comparison.first)); combine_hash(seed, h(comparison.second)); return seed; } - static void combine_hash(size_t &seed, size_t hash) { + static void + combine_hash(size_t& seed, size_t hash) + { seed ^= hash + 0x9e3779b97f4a7c15 + (seed << 12) + (seed >> 4); } }; @@ -170,21 +226,45 @@ using Outcomes = std::unordered_map<Comparison, Diff, HashComparison>; // unvisited (absent) -> started (false) -> finished (true) using Seen = std::unordered_map<Comparison, bool, HashComparison>; -void Print(const Comparison &comparison, const Outcomes &outcomes, Seen &seen, - NameCache &names, std::ostream &os, size_t indent = 0); - -void Print(const Diff &details, const Outcomes &outcomes, Seen &seen, - NameCache &names, std::ostream &os, size_t indent = 0); - -class Type { - public: - Type(const std::vector<std::unique_ptr<Type>> &types, uint32_t index, +void +Print(const Comparison& comparison, + const Outcomes& outcomes, + Seen& seen, + NameCache& names, + std::ostream& os, + size_t indent = 0); + +void +Print(const Diff& details, + const Outcomes& outcomes, + Seen& seen, + NameCache& names, + std::ostream& os, + size_t indent = 0); + +class Type +{ +public: + Type(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, Kind kind) - : types_(types), index_(index), kind_(kind) {} + : types_(types), index_(index), kind_(kind) + { + } virtual ~Type() = default; - uint32_t GetIndex() const { return index_; } - Kind GetKind() const { return kind_; } - const std::vector<std::unique_ptr<Type>> &GetTypes() const { + uint32_t + GetIndex() const + { + return index_; + } + Kind + GetKind() const + { + return kind_; + } + const std::vector<std::unique_ptr<Type>>& + GetTypes() const + { return types_; } @@ -193,10 +273,12 @@ class Type { // not correct, the assert will trigger in debug mode. In release mode, this // will crash dereferencing the nullptr. template <typename Target> - const Target &as() const { - static_assert(std::is_convertible<Target *, Type *>::value, - "Target must publically inherit Type"); - const Target *t = dynamic_cast<const Target *>(this); + const Target& + as() const + { + static_assert(std::is_convertible<Target*, Type*>::value, + "Target must publically inherit Type"); + const Target* t = dynamic_cast<const Target*>(this); m_assert(t, "Invalid downcast"); return *t; } @@ -204,126 +286,215 @@ class Type { // // The caller must always be prepared to receive a different type as // qualifiers are sometimes discarded. - virtual const Type &ResolveQualifiers(std::set<Kind> &qualifiers) const; - virtual const Type &ResolveTypedef( - std::vector<std::string> &typedefs) const; - - const Name &GetDescription(NameCache &names) const; - static Result CompareSymbols( - const std::map<std::string, const Type *const> &lhs, - const std::map<std::string, const Type *const> &rhs, - Outcomes &outcomes); - - protected: - struct State { - explicit State(Outcomes &o) : outcomes(o) { } - Outcomes &outcomes; + virtual const Type& + ResolveQualifiers(std::set<Kind>& qualifiers) const; + virtual const Type& + ResolveTypedef(std::vector<std::string>& typedefs) const; + + const Name& + GetDescription(NameCache& names) const; + static Result + CompareSymbols(const std::map<std::string, const Type* const>& lhs, + const std::map<std::string, const Type* const>& rhs, + Outcomes& outcomes); + +protected: + struct State + { + explicit State(Outcomes& o) : outcomes(o) {} + Outcomes& outcomes; std::unordered_set<Comparison, HashComparison> known_equal; Outcomes provisional; SCC<Comparison, HashComparison> scc; }; - const Type &GetTypeAtIndex(size_t index) const; - - virtual Name MakeDescription(NameCache &names) const = 0; - virtual Result Equals(const Type &other, State &state) const = 0; - static Comparison Removed(const Type &lhs, State &state); - static Comparison Added(const Type &rhs, State &state); - static std::pair<bool, std::optional<Comparison>> Compare( - const Type &lhs, const Type &rhs, State &state); - - private: - static std::string GetDiffMessage(NameCache &names, - const Type &lhs, const Type &rhs, - const std::string &message = std::string()); - const std::vector<std::unique_ptr<Type>> &types_; + const Type& + GetTypeAtIndex(size_t index) const; + + virtual Name + MakeDescription(NameCache& names) const = 0; + virtual Result + Equals(const Type& other, State& state) const = 0; + static Comparison + Removed(const Type& lhs, State& state); + static Comparison + Added(const Type& rhs, State& state); + static std::pair<bool, std::optional<Comparison>> + Compare(const Type& lhs, const Type& rhs, State& state); + +private: + static std::string + GetDiffMessage(NameCache& names, + const Type& lhs, + const Type& rhs, + const std::string& message = std::string()); + const std::vector<std::unique_ptr<Type>>& types_; const uint32_t index_; const Kind kind_; }; -class Void : public Type { - public: - Void(const std::vector<std::unique_ptr<Type>> &types, uint32_t index, +class Void : public Type +{ +public: + Void(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, Kind kind) - : Type(types, index, kind) {} - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; + : Type(types, index, kind) + { + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; }; -class Ptr : public Type { - public: - Ptr(const std::vector<std::unique_ptr<Type>> &types, uint32_t index, - Kind kind, uint32_t pointeeTypeId) - : Type(types, index, kind), - pointeeTypeId_(pointeeTypeId) {} - uint32_t GetPointeeTypeId() const { return pointeeTypeId_; } - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; - - private: +class Ptr : public Type +{ +public: + Ptr(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, + Kind kind, + uint32_t pointeeTypeId) + : Type(types, index, kind), pointeeTypeId_(pointeeTypeId) + { + } + uint32_t + GetPointeeTypeId() const + { + return pointeeTypeId_; + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; + +private: const uint32_t pointeeTypeId_; }; -class Typedef : public Type { - public: - Typedef(const std::vector<std::unique_ptr<Type>> &types, uint32_t index, - const std::string &name, Kind kind, uint32_t referredTypeId) - : Type(types, index, kind), - name_(name), - referredTypeId_(referredTypeId) {} - const std::string &GetName() const { return name_; } - uint32_t GetReferredTypeId() const { return referredTypeId_; } - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; - const Type &ResolveTypedef( - std::vector<std::string> &typedefs) const final; - - private: +class Typedef : public Type +{ +public: + Typedef(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, + const std::string& name, + Kind kind, + uint32_t referredTypeId) + : Type(types, index, kind), name_(name), referredTypeId_(referredTypeId) + { + } + const std::string& + GetName() const + { + return name_; + } + uint32_t + GetReferredTypeId() const + { + return referredTypeId_; + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; + const Type& + ResolveTypedef(std::vector<std::string>& typedefs) const final; + +private: const std::string name_; const uint32_t referredTypeId_; }; -class Qualifier : public Type { - public: - Qualifier(const std::vector<std::unique_ptr<Type>> &types, - uint32_t index, Kind kind, uint32_t qualifiedTypeId) - : Type(types, index, kind), - qualifiedTypeId_(qualifiedTypeId) {} - uint32_t GetQualifiedTypeId() const { return qualifiedTypeId_; } - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; - const Type &ResolveQualifiers(std::set<Kind> &qualifiers) const final; - - private: +class Qualifier : public Type +{ +public: + Qualifier(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, + Kind kind, + uint32_t qualifiedTypeId) + : Type(types, index, kind), qualifiedTypeId_(qualifiedTypeId) + { + } + uint32_t + GetQualifiedTypeId() const + { + return qualifiedTypeId_; + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; + const Type& + ResolveQualifiers(std::set<Kind>& qualifiers) const final; + +private: const uint32_t qualifiedTypeId_; }; -class Integer : public Type { - public: - Integer(const std::vector<std::unique_ptr<Type>> &types, uint32_t index, - const std::string &name, Kind kind, uint32_t encoding, - uint32_t offset, uint32_t bitsize, uint32_t bytesize) - : Type(types, index, kind), - name_(name), - offset_(offset), - bitsize_(bitsize), - bytesize_(bytesize), - isBool_(encoding & BTF_INT_BOOL), - isSigned_(encoding & BTF_INT_SIGNED), - isChar_(encoding & BTF_INT_CHAR) {} - const std::string &GetName() const { return name_; } - bool isBool() const { return isBool_; } - bool isSigned() const { return isSigned_; } - bool isChar() const { return isChar_; } - uint32_t GetOffset() const { return offset_; } +class Integer : public Type +{ +public: + Integer(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, + const std::string& name, + Kind kind, + uint32_t encoding, + uint32_t offset, + uint32_t bitsize, + uint32_t bytesize) + : Type(types, index, kind), + name_(name), + offset_(offset), + bitsize_(bitsize), + bytesize_(bytesize), + isBool_(encoding & BTF_INT_BOOL), + isSigned_(encoding & BTF_INT_SIGNED), + isChar_(encoding & BTF_INT_CHAR) + { + } + const std::string& + GetName() const + { + return name_; + } + bool + isBool() const + { + return isBool_; + } + bool + isSigned() const + { + return isSigned_; + } + bool + isChar() const + { + return isChar_; + } + uint32_t + GetOffset() const + { + return offset_; + } // GetBitSize() gives the semantics of the field. GetByteSize() gives the // storage size, and is equal or greater than GetBitSize()*8 - uint32_t GetBitSize() const { return bitsize_; } - uint32_t GetByteSize() const { return bytesize_; } - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; + uint32_t + GetBitSize() const + { + return bitsize_; + } + uint32_t + GetByteSize() const + { + return bytesize_; + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; - private: +private: const std::string name_; const uint32_t offset_; const uint32_t bitsize_; @@ -333,250 +504,443 @@ class Integer : public Type { const bool isChar_; }; -class Array : public Type { - public: - Array(const std::vector<std::unique_ptr<Type>> &types, uint32_t index, - Kind kind, uint32_t elementTypeId, uint32_t indexTypeId, - uint32_t numOfElements) - : Type(types, index, kind), - elementTypeId_(elementTypeId), - indexTypeId_(indexTypeId), - numOfElements_(numOfElements) {} - uint32_t GetElementTypeId() const { return elementTypeId_; } - uint32_t GetIndexTypeId() const { return indexTypeId_; } - uint32_t GetNumberOfElements() const { return numOfElements_; } - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; - - private: +class Array : public Type +{ +public: + Array(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, + Kind kind, + uint32_t elementTypeId, + uint32_t indexTypeId, + uint32_t numOfElements) + : Type(types, index, kind), + elementTypeId_(elementTypeId), + indexTypeId_(indexTypeId), + numOfElements_(numOfElements) + { + } + uint32_t + GetElementTypeId() const + { + return elementTypeId_; + } + uint32_t + GetIndexTypeId() const + { + return indexTypeId_; + } + uint32_t + GetNumberOfElements() const + { + return numOfElements_; + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; + +private: const uint32_t elementTypeId_; const uint32_t indexTypeId_; const uint32_t numOfElements_; }; -class StructUnion : public Type { - public: - StructUnion(const std::vector<std::unique_ptr<Type>> &types, - uint32_t index, const std::string &name, Kind kind, - uint32_t bytesize, std::map<std::string, Member> members) - : Type(types, index, kind), - name_(name), - bytesize_(bytesize), - members_(members) {} - const std::string &GetName() const { return name_; } - uint32_t GetByteSize() const { return bytesize_; } - const std::map<std::string, Member> &GetMembers() const { return members_; } - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; - - private: +class StructUnion : public Type +{ +public: + StructUnion(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, + const std::string& name, + Kind kind, + uint32_t bytesize, + std::map<std::string, Member> members) + : Type(types, index, kind), + name_(name), + bytesize_(bytesize), + members_(members) + { + } + const std::string& + GetName() const + { + return name_; + } + uint32_t + GetByteSize() const + { + return bytesize_; + } + const std::map<std::string, Member>& + GetMembers() const + { + return members_; + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; + +private: const std::string name_; const uint32_t bytesize_; const std::map<std::string, Member> members_; }; -class Enumeration : public Type { - public: - Enumeration(const std::vector<std::unique_ptr<Type>> &types, - uint32_t index, const std::string &name, Kind kind, - uint32_t bytesize, std::map<std::string, int> enumerators) - : Type(types, index, kind), - name_(name), - bytesize_(bytesize), - enumerators_(enumerators) {} - const std::string &GetName() const { return name_; } - uint32_t GetByteSize() const { return bytesize_; } - const std::map<std::string, int> &GetEnums() const { return enumerators_; } - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; - - private: +class Enumeration : public Type +{ +public: + Enumeration(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, + const std::string& name, + Kind kind, + uint32_t bytesize, + std::map<std::string, int> enumerators) + : Type(types, index, kind), + name_(name), + bytesize_(bytesize), + enumerators_(enumerators) + { + } + const std::string& + GetName() const + { + return name_; + } + uint32_t + GetByteSize() const + { + return bytesize_; + } + const std::map<std::string, int>& + GetEnums() const + { + return enumerators_; + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; + +private: const std::string name_; const uint32_t bytesize_; const std::map<std::string, int> enumerators_; }; -// BTF only considers structs and unions as forward-declared types, and does not -// include forward-declared enums. They are treated as BTF_KIND_ENUMs with vlen -// set to zero -class ForwardDeclaration : public Type { - public: - ForwardDeclaration(const std::vector<std::unique_ptr<Type>> &types, - uint32_t index, const std::string &name, Kind kind, - bool isUnion) - : Type(types, index, kind), - name_(name), - fwdKind_(isUnion ? ForwardDeclarationKind::UNION - : ForwardDeclarationKind::STRUCT) {} - const std::string &GetName() const { return name_; } - ForwardDeclarationKind GetFwdKind() const { return fwdKind_; } - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; - - private: +// BTF only considers structs and unions as forward-declared types, and does +// not include forward-declared enums. They are treated as BTF_KIND_ENUMs with +// vlen set to zero +class ForwardDeclaration : public Type +{ +public: + ForwardDeclaration(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, + const std::string& name, + Kind kind, + bool isUnion) + : Type(types, index, kind), + name_(name), + fwdKind_(isUnion ? ForwardDeclarationKind::UNION + : ForwardDeclarationKind::STRUCT) + { + } + const std::string& + GetName() const + { + return name_; + } + ForwardDeclarationKind + GetFwdKind() const + { + return fwdKind_; + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; + +private: const std::string name_; const ForwardDeclarationKind fwdKind_; }; -class Function : public Type { - public: - enum class Linkage : uint16_t { STATIC, GLOBAL, EXTERN }; - Function(const std::vector<std::unique_ptr<Type>> &types, - uint32_t index, const std::string &name, Kind kind, - uint32_t referredTypeId, Linkage linkage) - : Type(types, index, kind), - name_(name), - referredTypeId_(referredTypeId), - linkage_(linkage) {} - const std::string &GetName() const { return name_; } - uint32_t GetReferredTypeId() const { return referredTypeId_; } - Linkage GetLinkage() const { return linkage_; } - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; - - private: +class Function : public Type +{ +public: + enum class Linkage : uint16_t + { + STATIC, + GLOBAL, + EXTERN + }; + Function(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, + const std::string& name, + Kind kind, + uint32_t referredTypeId, + Linkage linkage) + : Type(types, index, kind), + name_(name), + referredTypeId_(referredTypeId), + linkage_(linkage) + { + } + const std::string& + GetName() const + { + return name_; + } + uint32_t + GetReferredTypeId() const + { + return referredTypeId_; + } + Linkage + GetLinkage() const + { + return linkage_; + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; + +private: const std::string name_; const uint32_t referredTypeId_; const Linkage linkage_; }; -class FunctionPrototype : public Type { - public: - FunctionPrototype(const std::vector<std::unique_ptr<Type>> &types, - uint32_t index, Kind kind, uint32_t returnTypeId, - std::vector<Parameter> parameters) - : Type(types, index, kind), - returnTypeId_(returnTypeId), - parameters_(parameters) {} - uint32_t GetReturnTypeId() const { return returnTypeId_; } - const std::vector<Parameter> &GetParameters() const { return parameters_; } - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; - - private: +class FunctionPrototype : public Type +{ +public: + FunctionPrototype(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, + Kind kind, + uint32_t returnTypeId, + std::vector<Parameter> parameters) + : Type(types, index, kind), + returnTypeId_(returnTypeId), + parameters_(parameters) + { + } + uint32_t + GetReturnTypeId() const + { + return returnTypeId_; + } + const std::vector<Parameter>& + GetParameters() const + { + return parameters_; + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; + +private: const uint32_t returnTypeId_; const std::vector<Parameter> parameters_; }; -class Variable : public Type { - public: - enum class Linkage : uint32_t { STATIC, GLOBAL_ALLOC, GLOBAL_EXTERN }; - Variable(const std::vector<std::unique_ptr<Type>> &types, - uint32_t index, const std::string &name, Kind kind, - unsigned varTypeId, Linkage linkage) - : Type(types, index, kind), - name_(name), - varTypeId_(varTypeId), - linkage_(linkage) {} - const std::string &GetName() const { return name_; } - uint32_t GetVarTypeId() const { return varTypeId_; } - Linkage GetLinkage() const { return linkage_; } - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; - - private: +class Variable : public Type +{ +public: + enum class Linkage : uint32_t + { + STATIC, + GLOBAL_ALLOC, + GLOBAL_EXTERN + }; + Variable(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, + const std::string& name, + Kind kind, + unsigned varTypeId, + Linkage linkage) + : Type(types, index, kind), + name_(name), + varTypeId_(varTypeId), + linkage_(linkage) + { + } + const std::string& + GetName() const + { + return name_; + } + uint32_t + GetVarTypeId() const + { + return varTypeId_; + } + Linkage + GetLinkage() const + { + return linkage_; + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; + +private: const std::string name_; const uint32_t varTypeId_; const Linkage linkage_; }; -class DataSection : public Type { - public: - DataSection(const std::vector<std::unique_ptr<Type>> &types, - uint32_t index, Kind kind, uint32_t bytesize, - std::vector<Secinfo> secinfos) - : Type(types, index, kind), - bytesize_(bytesize), - secinfos_(secinfos) {} - uint32_t GetByteSize() const { return bytesize_; } - const std::vector<Secinfo> &GetSecinfos() const { return secinfos_; } - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; - - private: +class DataSection : public Type +{ +public: + DataSection(const std::vector<std::unique_ptr<Type>>& types, + uint32_t index, + Kind kind, + uint32_t bytesize, + std::vector<Secinfo> secinfos) + : Type(types, index, kind), bytesize_(bytesize), secinfos_(secinfos) + { + } + uint32_t + GetByteSize() const + { + return bytesize_; + } + const std::vector<Secinfo>& + GetSecinfos() const + { + return secinfos_; + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; + +private: const uint32_t bytesize_; const std::vector<Secinfo> secinfos_; }; // Not actually a BTF type but needed for uniformity of representation. -class ElfSymbol : public Type { - public: - ElfSymbol(const std::vector<std::unique_ptr<Type>> &types, - abigail::elf_symbol_sptr symbol, uint32_t type_id) - : Type(types, -1, -1), symbol_(symbol), type_id_(type_id) {} - abigail::elf_symbol_sptr GetElfSymbol() const { return symbol_; } - uint32_t GetTypeId() const { return type_id_; } - Name MakeDescription(NameCache &names) const final; - Result Equals(const Type &other, State &state) const final; - - private: +class ElfSymbol : public Type +{ +public: + ElfSymbol(const std::vector<std::unique_ptr<Type>>& types, + abigail::elf_symbol_sptr symbol, + uint32_t type_id) + : Type(types, -1, -1), symbol_(symbol), type_id_(type_id) + { + } + abigail::elf_symbol_sptr + GetElfSymbol() const + { + return symbol_; + } + uint32_t + GetTypeId() const + { + return type_id_; + } + Name + MakeDescription(NameCache& names) const final; + Result + Equals(const Type& other, State& state) const final; + +private: abigail::elf_symbol_sptr symbol_; uint32_t type_id_; }; -std::ostream &operator<<(std::ostream &os, const Ptr &bp); -std::ostream &operator<<(std::ostream &os, const Typedef &bp); -std::ostream &operator<<(std::ostream &os, const Qualifier &bp); -std::ostream &operator<<(std::ostream &os, const Integer &bi); -std::ostream &operator<<(std::ostream &os, const Array &ba); -std::ostream &operator<<(std::ostream &os, const StructUnion &bsu); -std::ostream &operator<<(std::ostream &os, const Enumeration &be); -std::ostream &operator<<(std::ostream &os, const ForwardDeclaration &bfd); -std::ostream &operator<<(std::ostream &os, const Function &bf); -std::ostream &operator<<(std::ostream &os, const FunctionPrototype &bfp); -std::ostream &operator<<(std::ostream &os, const Variable &bv); -std::ostream &operator<<(std::ostream &os, const DataSection &bds); -std::ostream &operator<<(std::ostream &os, const ElfSymbol &bes); -std::ostream &operator<<(std::ostream &os, Variable::Linkage linkage); -std::ostream &operator<<(std::ostream &os, Function::Linkage linkage); +std::ostream& +operator<<(std::ostream& os, const Ptr& bp); +std::ostream& +operator<<(std::ostream& os, const Typedef& bp); +std::ostream& +operator<<(std::ostream& os, const Qualifier& bp); +std::ostream& +operator<<(std::ostream& os, const Integer& bi); +std::ostream& +operator<<(std::ostream& os, const Array& ba); +std::ostream& +operator<<(std::ostream& os, const StructUnion& bsu); +std::ostream& +operator<<(std::ostream& os, const Enumeration& be); +std::ostream& +operator<<(std::ostream& os, const ForwardDeclaration& bfd); +std::ostream& +operator<<(std::ostream& os, const Function& bf); +std::ostream& +operator<<(std::ostream& os, const FunctionPrototype& bfp); +std::ostream& +operator<<(std::ostream& os, const Variable& bv); +std::ostream& +operator<<(std::ostream& os, const DataSection& bds); +std::ostream& +operator<<(std::ostream& os, const ElfSymbol& bes); +std::ostream& +operator<<(std::ostream& os, Variable::Linkage linkage); +std::ostream& +operator<<(std::ostream& os, Function::Linkage linkage); // BTF Specification: https://www.kernel.org/doc/html/latest/bpf/btf.html -class Structs { - public: - Structs(const char *start, std::unique_ptr<abigail::ir::environment> env, - const abigail::symtab_reader::symtab_sptr tab, - const bool verbose = false); +class Structs +{ +public: + Structs(const char* start, + std::unique_ptr<abigail::ir::environment> env, + const abigail::symtab_reader::symtab_sptr tab, + const bool verbose = false); ~Structs() = default; - void PrintHeader(); - void BuildTypes(); - void PrintStringSection(); - const std::map<std::string, const Type *const> &GetSymbols( - bool use_elf_symbols) const { + void + PrintHeader(); + void + BuildTypes(); + void + PrintStringSection(); + const std::map<std::string, const Type* const>& + GetSymbols(bool use_elf_symbols) const + { return use_elf_symbols ? elf_symbols_ : btf_symbols_; } - private: - const btf_header *header_; - const btf_type *type_section_; - const char *str_section_; +private: + const btf_header* header_; + const btf_type* type_section_; + const char* str_section_; const std::unique_ptr<abigail::ir::environment> env_; const abigail::symtab_reader::symtab_sptr tab_; const bool verbose_; std::vector<std::unique_ptr<Type>> types_; std::unordered_map<std::string, uint32_t> btf_symbol_types_; - std::map<std::string, const Type *const> btf_symbols_; - std::map<std::string, const Type *const> elf_symbols_; + std::map<std::string, const Type* const> btf_symbols_; + std::map<std::string, const Type* const> elf_symbols_; std::vector<std::string> bad_names_; std::string bad_prefix_1_; std::string bad_prefix_2_; - int BuildOneType(const btf_type *t, uint32_t index); - void BuildElfSymbols(); - std::map<std::string, Member> BuildMembers( - bool kflag, const btf_member *members, size_t vlen); - std::map<std::string, int> BuildEnums(const struct btf_enum *enums, - size_t vlen); - std::vector<Parameter> BuildParams(const struct btf_param *params, - size_t vlen); - std::vector<Secinfo> BuildDatasec(const btf_type *type, size_t vlen); - std::string GetName(uint32_t name_off); + int + BuildOneType(const btf_type* t, uint32_t index); + void + BuildElfSymbols(); + std::map<std::string, Member> + BuildMembers(bool kflag, const btf_member* members, size_t vlen); + std::map<std::string, int> + BuildEnums(const struct btf_enum* enums, size_t vlen); + std::vector<Parameter> + BuildParams(const struct btf_param* params, size_t vlen); + std::vector<Secinfo> + BuildDatasec(const btf_type* type, size_t vlen); + std::string + GetName(uint32_t name_off); }; -Structs ReadFile(const std::string &path, bool verbose = false); +Structs +ReadFile(const std::string& path, bool verbose = false); -} // end namespace btf -} // end namespace abigail +} // end namespace btf +} // end namespace abigail -#endif // __ABG_BTF_H__ +#endif // __ABG_BTF_H__ diff --git a/include/abg-scc.h b/include/abg-scc.h index 8c542e67..f1b3c8cc 100644 --- a/include/abg-scc.h +++ b/include/abg-scc.h @@ -14,7 +14,8 @@ #include <unordered_map> #include <vector> -namespace abigail { +namespace abigail +{ /* * This is a streamlined Strongly-Connected Component finder for use with @@ -47,10 +48,11 @@ namespace abigail { * USAGE * * Before examining a node, check it's not been assigned to an SCC already and - * then call Open. If the node is already "open" (i.e., is already waiting to be - * assigned to an SCC), this will return an empty optional value and the node - * should not be examined. If Open succeeds, a numerical node handle will be - * returned and the node will be recorded as waiting to be assigned to an SCC. + * then call Open. If the node is already "open" (i.e., is already waiting to + * be assigned to an SCC), this will return an empty optional value and the + * node should not be examined. If Open succeeds, a numerical node handle will + * be returned and the node will be recorded as waiting to be assigned to an + * SCC. * * Now examine the node, making recursive calls to follow edges to other nodes. * Infomation about the node can be stored provisionally, but must NOT be used @@ -62,50 +64,58 @@ namespace abigail { * the nodes as visited), this should be done now. Otherwise, an empty vector * will be returned. */ -template<typename Node, typename Hash = std::hash<Node>> class SCC { - public: - ~SCC() { +template <typename Node, typename Hash = std::hash<Node>> class SCC +{ +public: + ~SCC() + { assert(open_.empty()); assert(is_open_.empty()); assert(root_index_.empty()); } - std::optional<size_t> Open(const Node &node) { + std::optional<size_t> + Open(const Node& node) + { // Insertion will fail if the node is already open. auto [it, inserted] = is_open_.insert({node, is_open_.size()}); auto ix = it->second; - if (!inserted) { - // Pop indices to nodes which cannot be the root of their SCC. - while (root_index_.back() > ix) - root_index_.pop_back(); - return {}; - } + if (!inserted) + { + // Pop indices to nodes which cannot be the root of their SCC. + while (root_index_.back() > ix) + root_index_.pop_back(); + return {}; + } // Unvisited, record open node and record root index. open_.push_back(node); root_index_.push_back(ix); return ix; } - std::vector<Node> Close(size_t ix) { + std::vector<Node> + Close(size_t ix) + { std::vector<Node> scc; assert(ix < open_.size()); - if (ix == root_index_.back()) { - // Close SCC. - for (size_t o = ix; o < open_.size(); ++o) - is_open_.erase(open_[o]); - std::move(open_.begin() + ix, open_.end(), std::back_inserter(scc)); - open_.resize(ix); - root_index_.pop_back(); - } + if (ix == root_index_.back()) + { + // Close SCC. + for (size_t o = ix; o < open_.size(); ++o) + is_open_.erase(open_[o]); + std::move(open_.begin() + ix, open_.end(), std::back_inserter(scc)); + open_.resize(ix); + root_index_.pop_back(); + } return scc; } - private: - std::vector<Node> open_; // index to node - std::unordered_map<Node, size_t, Hash> is_open_; // node to index +private: + std::vector<Node> open_; // index to node + std::unordered_map<Node, size_t, Hash> is_open_; // node to index std::vector<size_t> root_index_; }; -} // namespace abigail +} // namespace abigail -#endif // __ABG_SCC_H__ +#endif // __ABG_SCC_H__ diff --git a/src/abg-btf.cc b/src/abg-btf.cc index 39a8e480..c681bf2e 100644 --- a/src/abg-btf.cc +++ b/src/abg-btf.cc @@ -21,64 +21,62 @@ #include "abg-btf.h" -namespace abigail { -namespace btf { +namespace abigail +{ +namespace btf +{ // This is a helper map that yields the name of a Type in the preferred // print style by indexing into the vector with a Kind static constexpr std::array<std::string_view, 16> kKindNames = { - "void type", - "integer type", - "pointer type", - "array type", - "struct type", - "union type", - "enum type", - "forward declaration", - "typedef", - "volatile", - "const", - "restrict", - "function", - "function type", - "variable", - "data section" -}; + "void type", + "integer type", + "pointer type", + "array type", + "struct type", + "union type", + "enum type", + "forward declaration", + "typedef", + "volatile", + "const", + "restrict", + "function", + "function type", + "variable", + "data section"}; // This matches bpftool dump format raw. static constexpr std::array<std::string_view, 16> kRawKindNames = { - "VOID", - "INT", - "PTR", - "ARRAY", - "STRUCT", - "UNION", - "ENUM", - "FWD", - "TYPEDEF", - "VOLATILE", - "CONST", - "RESTRICT", - "FUNC", - "FUNC_PROTO", - "VAR", - "DATASEC" -}; + "VOID", + "INT", + "PTR", + "ARRAY", + "STRUCT", + "UNION", + "ENUM", + "FWD", + "TYPEDEF", + "VOLATILE", + "CONST", + "RESTRICT", + "FUNC", + "FUNC_PROTO", + "VAR", + "DATASEC"}; static constexpr std::array<std::string_view, 3> kVarLinkage = { - "static", - "global-alloc", - "global-extern" // NOTE: bpftool currently says "(unknown)" + "static", + "global-alloc", + "global-extern" // NOTE: bpftool currently says "(unknown)" }; static constexpr std::array<std::string_view, 3> kFunLinkage = { - "static", - "global", - "extern" -}; + "static", "global", "extern"}; -Name Name::Add(Side side, Precedence precedence, - const std::string &text) const { +Name +Name::Add(Side side, Precedence precedence, const std::string& text) const +{ bool bracket = precedence < precedence_; std::ostringstream left; std::ostringstream right; @@ -100,32 +98,43 @@ Name Name::Add(Side side, Precedence precedence, return Name{left.str(), precedence, right.str()}; } -Name Name::Qualify(const std::set<Kind> &qualifiers) const { +Name +Name::Qualify(const std::set<Kind>& qualifiers) const +{ // this covers the case when bad qualifiers have been dropped if (qualifiers.empty()) return *this; // add qualifiers to the left or right of the type stem std::ostringstream os; - if (precedence_ == Precedence::NIL) { - for (const auto &qualifier : qualifiers) - os << kKindNames[qualifier] << ' '; - os << left_; - } else if (precedence_ == Precedence::POINTER) { - os << left_; - for (const auto &qualifier : qualifiers) - os << ' ' << kKindNames[qualifier]; - } else { - m_assert(false, "unqualifiable element"); - } + if (precedence_ == Precedence::NIL) + { + for (const auto& qualifier : qualifiers) + os << kKindNames[qualifier] << ' '; + os << left_; + } + else if (precedence_ == Precedence::POINTER) + { + os << left_; + for (const auto& qualifier : qualifiers) + os << ' ' << kKindNames[qualifier]; + } + else + { + m_assert(false, "unqualifiable element"); + } // qualifiers attach without affecting precedence return Name{os.str(), precedence_, right_}; } -std::ostream &Name::Print(std::ostream &os) const { +std::ostream& +Name::Print(std::ostream& os) const +{ return os << left_ << right_; } -std::ostream &operator<<(std::ostream &os, const Name &name) { +std::ostream& +operator<<(std::ostream& os, const Name& name) +{ return name.Print(os); } @@ -134,47 +143,57 @@ std::ostream &operator<<(std::ostream &os, const Name &name) { // 2. Qualifiers need to be placed according to what they qualify. // 3. The BTF model doesn't preclude ordering and duplication issues. // 4. A better model would have qualifiers as part of the types. -const Name &Type::GetDescription(NameCache &names) const { +const Name& +Type::GetDescription(NameCache& names) const +{ // infinite recursion prevention - insert at most once static const Name black_hole{"#"}; auto insertion = names.insert({this, black_hole}); - Name &cached = insertion.first->second; - - if (insertion.second) { - // newly inserted, need to determine name of type - std::set<Kind> qualifiers; - const Type &under = ResolveQualifiers(qualifiers); - if (this == &under) { - // unqualified, simple case - cached = MakeDescription(names); - } else { - // qualified, but we may end up adding no qualifiers - auto insertion_under = names.insert({&under, black_hole}); - Name &cached_under = insertion_under.first->second; - - // newly inserted underlying type name - if (insertion_under.second) - cached_under = under.MakeDescription(names); - - // add the qualifiers (to the appropriate side) - cached = cached_under.Qualify(qualifiers); + Name& cached = insertion.first->second; + + if (insertion.second) + { + // newly inserted, need to determine name of type + std::set<Kind> qualifiers; + const Type& under = ResolveQualifiers(qualifiers); + if (this == &under) + { + // unqualified, simple case + cached = MakeDescription(names); + } + else + { + // qualified, but we may end up adding no qualifiers + auto insertion_under = names.insert({&under, black_hole}); + Name& cached_under = insertion_under.first->second; + + // newly inserted underlying type name + if (insertion_under.second) + cached_under = under.MakeDescription(names); + + // add the qualifiers (to the appropriate side) + cached = cached_under.Qualify(qualifiers); + } } - } return cached; } -std::string GetPlainDescription(NameCache &names, const Type &type) { +std::string +GetPlainDescription(NameCache& names, const Type& type) +{ std::ostringstream os; os << '"' << type.GetDescription(names) << '"'; return os.str(); } -std::string GetTypedefDescription(NameCache &names, const Type &given) { +std::string +GetTypedefDescription(NameCache& names, const Type& given) +{ std::ostringstream os; std::vector<std::string> typedefs; - const Type &type = given.ResolveTypedef(typedefs); + const Type& type = given.ResolveTypedef(typedefs); for (auto td : typedefs) os << std::quoted(td) << " = "; os << GetPlainDescription(names, type); @@ -183,74 +202,99 @@ std::string GetTypedefDescription(NameCache &names, const Type &given) { constexpr size_t INDENT_INCREMENT = 2; -void Print(const Comparison &comparison, const Outcomes &outcomes, Seen &seen, - NameCache &names, std::ostream &os, size_t indent) { - const auto *lhs = comparison.first; - const auto *rhs = comparison.second; - if (!rhs) { - os << GetPlainDescription(names, *lhs) << " was removed\n"; - return; - } - if (!lhs) { - os << GetPlainDescription(names, *rhs) << " was added\n"; - return; - } - bool td = lhs->GetKind() == BTF_KIND_TYPEDEF - || rhs->GetKind() == BTF_KIND_TYPEDEF; +void +Print(const Comparison& comparison, + const Outcomes& outcomes, + Seen& seen, + NameCache& names, + std::ostream& os, + size_t indent) +{ + const auto* lhs = comparison.first; + const auto* rhs = comparison.second; + if (!rhs) + { + os << GetPlainDescription(names, *lhs) << " was removed\n"; + return; + } + if (!lhs) + { + os << GetPlainDescription(names, *rhs) << " was added\n"; + return; + } + bool td = + lhs->GetKind() == BTF_KIND_TYPEDEF || rhs->GetKind() == BTF_KIND_TYPEDEF; const std::string lhs_descr = td ? GetTypedefDescription(names, *lhs) - : GetPlainDescription(names, *lhs); + : GetPlainDescription(names, *lhs); const std::string rhs_descr = td ? GetTypedefDescription(names, *rhs) - : GetPlainDescription(names, *rhs); + : GetPlainDescription(names, *rhs); if (lhs_descr == rhs_descr) os << lhs_descr << " changed"; else os << "changed from " << lhs_descr << " to " << rhs_descr; - const auto &details = outcomes.find(comparison)->second; + const auto& details = outcomes.find(comparison)->second; auto insertion = seen.insert({comparison, false}); - if (!insertion.second) { - if (!insertion.first->second) - os << " (being reported)"; - else if (!details.empty()) - os << " (already reported)"; - } + if (!insertion.second) + { + if (!insertion.first->second) + os << " (being reported)"; + else if (!details.empty()) + os << " (already reported)"; + } os << '\n'; - if (insertion.second) { - Print(details, outcomes, seen, names, os, indent + INDENT_INCREMENT); - insertion.first->second = true; - } + if (insertion.second) + { + Print(details, outcomes, seen, names, os, indent + INDENT_INCREMENT); + insertion.first->second = true; + } // paragraph spacing if (!indent) os << '\n'; } -void Print(const Diff &details, const Outcomes &outcomes, Seen &seen, - NameCache &names, std::ostream &os, size_t indent) { - for (const auto &detail : details) { - os << std::string(indent, ' ') << detail.text_; - if (!detail.edge_) { - os << '\n'; - } else { - os << ' '; - Print(detail.edge_.value(), outcomes, seen, names, os, indent); +void +Print(const Diff& details, + const Outcomes& outcomes, + Seen& seen, + NameCache& names, + std::ostream& os, + size_t indent) +{ + for (const auto& detail : details) + { + os << std::string(indent, ' ') << detail.text_; + if (!detail.edge_) + { + os << '\n'; + } + else + { + os << ' '; + Print(detail.edge_.value(), outcomes, seen, names, os, indent); + } } - } } -const Type &Type::GetTypeAtIndex(size_t index) const { +const Type& +Type::GetTypeAtIndex(size_t index) const +{ m_assert(index < types_.size(), "Index out of bounds."); return *(types_[index].get()); } -std::string QualifiersMessage(Kind qualifier, const std::string &action) { +std::string +QualifiersMessage(Kind qualifier, const std::string& action) +{ std::ostringstream os; os << "qualifier " << kKindNames[qualifier] << ' ' << action; return os.str(); } -Result Type::CompareSymbols( - const std::map<std::string, const Type *const> &lhs, - const std::map<std::string, const Type *const> &rhs, - Outcomes &outcomes) { +Result +Type::CompareSymbols(const std::map<std::string, const Type* const>& lhs, + const std::map<std::string, const Type* const>& rhs, + Outcomes& outcomes) +{ Result result; State state(outcomes); auto lit = lhs.begin(); @@ -260,56 +304,76 @@ Result Type::CompareSymbols( // without BTF information may have changed type. // // NOTE: this currently happens for all global variables - while (lit != lhs.end() || rit != rhs.end()) { - if (rit == rhs.end() || (lit != lhs.end() && lit->first < rit->first)) { - // removed - if (lit->second) { - auto diff = Removed(*lit->second, state); - result.AddDiff("symbol", diff); - } else { - std::ostringstream os; - os << "symbol " << std::quoted(lit->first) - << " (of unknown type) was removed"; - result.AddDiff(os.str()); - } - ++lit; - } else if (lit == lhs.end() || (rit != rhs.end() && lit->first > rit->first)) { - // added - if (rit->second) { - auto diff = Added(*rit->second, state); - result.AddDiff("symbol", diff); - } else { - std::ostringstream os; - os << "symbol " << std::quoted(rit->first) - << " (if unknown type) was added"; - result.AddDiff(os.str()); - } - ++rit; - } else { - // in both - if (lit->second && rit->second) { - auto diff = Compare(*lit->second, *rit->second, state); - result.MaybeAddDiff("symbol", diff); - } else { - std::ostringstream os; - os << "symbol " << std::quoted(lit->first) - << " (of unknown type) may have changed"; - result.AddDiff(os.str()); - } - ++lit; - ++rit; + while (lit != lhs.end() || rit != rhs.end()) + { + if (rit == rhs.end() || (lit != lhs.end() && lit->first < rit->first)) + { + // removed + if (lit->second) + { + auto diff = Removed(*lit->second, state); + result.AddDiff("symbol", diff); + } + else + { + std::ostringstream os; + os << "symbol " << std::quoted(lit->first) + << " (of unknown type) was removed"; + result.AddDiff(os.str()); + } + ++lit; + } + else if (lit == lhs.end() + || (rit != rhs.end() && lit->first > rit->first)) + { + // added + if (rit->second) + { + auto diff = Added(*rit->second, state); + result.AddDiff("symbol", diff); + } + else + { + std::ostringstream os; + os << "symbol " << std::quoted(rit->first) + << " (if unknown type) was added"; + result.AddDiff(os.str()); + } + ++rit; + } + else + { + // in both + if (lit->second && rit->second) + { + auto diff = Compare(*lit->second, *rit->second, state); + result.MaybeAddDiff("symbol", diff); + } + else + { + std::ostringstream os; + os << "symbol " << std::quoted(lit->first) + << " (of unknown type) may have changed"; + result.AddDiff(os.str()); + } + ++lit; + ++rit; + } } - } return result; } -Comparison Type::Removed(const Type &lhs, State &state) { +Comparison +Type::Removed(const Type& lhs, State& state) +{ Comparison comparison{&lhs, nullptr}; state.outcomes.insert({comparison, {}}); return comparison; } -Comparison Type::Added(const Type &rhs, State &state) { +Comparison +Type::Added(const Type& rhs, State& state) +{ Comparison comparison{nullptr, &rhs}; state.outcomes.insert({comparison, {}}); return comparison; @@ -322,158 +386,198 @@ Comparison Type::Added(const Type &rhs, State &state) { * 1. equals = true; perhaps only tentative edge differences * 2. equals = false; at least one definitive node or edge difference * - * On the first visit to a node we can put a placeholder in, the equals value is - * irrelevant, the diff may contain local and edge differences. If an SCC + * On the first visit to a node we can put a placeholder in, the equals value + * is irrelevant, the diff may contain local and edge differences. If an SCC * contains only internal edge differences (and equivalently equals is true) * then the differences can all (eventually) be discarded. * * On exit from the first visit to a node, equals reflects the tree of - * comparisons below that node in the DFS and similarly, the diff graph starting - * from the node contains a subtree of this tree plus potentially edges to - * existing nodes to the side or below (already visited SCCs, sharing), or above - * (back links forming cycles). + * comparisons below that node in the DFS and similarly, the diff graph + * starting from the node contains a subtree of this tree plus potentially + * edges to existing nodes to the side or below (already visited SCCs, + * sharing), or above (back links forming cycles). * * When an SCC is closed, all equals implies deleting all diffs, any false * implies updating all to false. * * On subsequent visits to a node, there are 2 cases. The node is still open: - * return true and an edge diff. The node is closed, return the stored value and - * an edge diff. + * return true and an edge diff. The node is closed, return the stored value + * and an edge diff. */ -std::pair<bool, std::optional<Comparison>> Type::Compare( - const Type &lhs, const Type &rhs, Type::State &state) { +std::pair<bool, std::optional<Comparison>> +Type::Compare(const Type& lhs, const Type& rhs, Type::State& state) +{ const Comparison comparison{&lhs, &rhs}; // 1. Check if the comparison has an already known result. - if (state.known_equal.count(comparison)) { - // Already visited and closed. Equal. - return {true, {}}; - } - if (state.outcomes.count(comparison)) { - // Already visited and closed. Different. - return {false, {comparison}}; - } + if (state.known_equal.count(comparison)) + { + // Already visited and closed. Equal. + return {true, {}}; + } + if (state.outcomes.count(comparison)) + { + // Already visited and closed. Different. + return {false, {comparison}}; + } // Either open or not visited at all // 2. Record node with Strongly-Connected Component finder. auto handle = state.scc.Open(comparison); - if (!handle) { - // Already open. - // - // Return a dummy true outcome and some tentative diffs. The diffs may end - // up not being used and, while it would be nice to be lazier, they encode - // all the cycling-breaking edges needed to recreate a full diff structure. - return {true, {comparison}}; - } + if (!handle) + { + // Already open. + // + // Return a dummy true outcome and some tentative diffs. The diffs may + // end up not being used and, while it would be nice to be lazier, they + // encode all the cycling-breaking edges needed to recreate a full diff + // structure. + return {true, {comparison}}; + } // Comparison opened, need to close it before returning. Result result; std::set<Kind> lhs_quals; std::set<Kind> rhs_quals; - const Type &l = lhs.ResolveQualifiers(lhs_quals); - const Type &r = rhs.ResolveQualifiers(rhs_quals); - if (!lhs_quals.empty() || !rhs_quals.empty()) { - // 3.1 Qualified type difference. - auto lit = lhs_quals.begin(); - auto rit = rhs_quals.begin(); - auto lend = lhs_quals.end(); - auto rend = rhs_quals.end(); - while (lit != lend || rit != rend) { - if (rit == rend || (lit != lend && *lit < *rit)) { - result.AddDiff(QualifiersMessage(*lit, "removed")); - ++lit; - } else if (lit == lend || (rit != rend && *lit > *rit)) { - result.AddDiff(QualifiersMessage(*rit, "added")); - ++rit; - } else { - ++lit; - ++rit; - } + const Type& l = lhs.ResolveQualifiers(lhs_quals); + const Type& r = rhs.ResolveQualifiers(rhs_quals); + if (!lhs_quals.empty() || !rhs_quals.empty()) + { + // 3.1 Qualified type difference. + auto lit = lhs_quals.begin(); + auto rit = rhs_quals.begin(); + auto lend = lhs_quals.end(); + auto rend = rhs_quals.end(); + while (lit != lend || rit != rend) + { + if (rit == rend || (lit != lend && *lit < *rit)) + { + result.AddDiff(QualifiersMessage(*lit, "removed")); + ++lit; + } + else if (lit == lend || (rit != rend && *lit > *rit)) + { + result.AddDiff(QualifiersMessage(*rit, "added")); + ++rit; + } + else + { + ++lit; + ++rit; + } + } + const auto comp = Compare(l, r, state); + result.MaybeAddDiff("underlying type", comp); + } + else if (l.GetKind() == BTF_KIND_TYPEDEF || r.GetKind() == BTF_KIND_TYPEDEF) + { + // 3.2 Typedef difference. + std::vector<std::string> l_typedefs; + std::vector<std::string> r_typedefs; + const Type& l_ref = l.ResolveTypedef(l_typedefs); + const Type& r_ref = r.ResolveTypedef(r_typedefs); + const auto comp = Compare(l_ref, r_ref, state); + result.MaybeAddDiff("via typedefs", comp); + } + else if (typeid(l) != typeid(r)) + { + // 4. Incomparable. + result.equals_ = false; + } + else + { + // 5. Actually compare with dynamic type dispatch. + result = l.Equals(r, state); } - const auto comp = Compare(l, r, state); - result.MaybeAddDiff("underlying type", comp); - } else if (l.GetKind() == BTF_KIND_TYPEDEF - || r.GetKind() == BTF_KIND_TYPEDEF) { - // 3.2 Typedef difference. - std::vector<std::string> l_typedefs; - std::vector<std::string> r_typedefs; - const Type &l_ref = l.ResolveTypedef(l_typedefs); - const Type &r_ref = r.ResolveTypedef(r_typedefs); - const auto comp = Compare(l_ref, r_ref, state); - result.MaybeAddDiff("via typedefs", comp); - } else if (typeid(l) != typeid(r)) { - // 4. Incomparable. - result.equals_ = false; - } else { - // 5. Actually compare with dynamic type dispatch. - result = l.Equals(r, state); - } // 6. Update result and check for a complete Strongly-Connected Component. state.provisional.insert({comparison, result.details_}); auto comparisons = state.scc.Close(handle.value()); - if (!comparisons.empty()) { - // Closed SCC. - // - // Note that result now incorporates every inequality and difference in the - // SCC via the DFS spanning tree. - if (result.equals_) { - // Same. Record equalities. - for (auto &c : comparisons) - state.known_equal.insert(c); - return {true, {}}; - } else { - // Different. Record diffs. - for (auto &c : comparisons) { - auto it = state.provisional.find(c); - state.outcomes.insert(*it); - state.provisional.erase(it); - } + if (!comparisons.empty()) + { + // Closed SCC. + // + // Note that result now incorporates every inequality and difference in + // the SCC via the DFS spanning tree. + if (result.equals_) + { + // Same. Record equalities. + for (auto& c : comparisons) + state.known_equal.insert(c); + return {true, {}}; + } + else + { + // Different. Record diffs. + for (auto& c : comparisons) + { + auto it = state.provisional.find(c); + state.outcomes.insert(*it); + state.provisional.erase(it); + } + } } - } // Note that both equals and diff are tentative iff comparison is open. return {result.equals_, {comparison}}; } -Name Void::MakeDescription(NameCache &names) const { +Name +Void::MakeDescription(NameCache& names) const +{ return Name{"void"}; } -Name Ptr::MakeDescription(NameCache &names) const { - return GetTypeAtIndex(GetPointeeTypeId()).GetDescription(names).Add( - Side::LEFT, Precedence::POINTER, "*"); +Name +Ptr::MakeDescription(NameCache& names) const +{ + return GetTypeAtIndex(GetPointeeTypeId()) + .GetDescription(names) + .Add(Side::LEFT, Precedence::POINTER, "*"); } -Name Typedef::MakeDescription(NameCache &names) const { +Name +Typedef::MakeDescription(NameCache& names) const +{ return Name{GetName()}; } -Name Qualifier::MakeDescription(NameCache &names) const { - m_assert(false, "should not be called"); // NOLINT +Name +Qualifier::MakeDescription(NameCache& names) const +{ + m_assert(false, "should not be called"); // NOLINT return Name{"qualifier"}; } -Name Integer::MakeDescription(NameCache &names) const { +Name +Integer::MakeDescription(NameCache& names) const +{ return Name{GetName()}; } -Name Array::MakeDescription(NameCache &names) const { +Name +Array::MakeDescription(NameCache& names) const +{ std::ostringstream os; os << '[' << GetNumberOfElements() << ']'; - return GetTypeAtIndex(GetElementTypeId()).GetDescription(names).Add( - Side::RIGHT, Precedence::ARRAY_FUNCTION, os.str()); + return GetTypeAtIndex(GetElementTypeId()) + .GetDescription(names) + .Add(Side::RIGHT, Precedence::ARRAY_FUNCTION, os.str()); } -Name StructUnion::MakeDescription(NameCache &names) const { +Name +StructUnion::MakeDescription(NameCache& names) const +{ std::ostringstream os; - os << (GetKind() == BTF_KIND_STRUCT ? "struct" : "union") - << ' ' << (GetName().empty() ? "<anon>" : GetName()); + os << (GetKind() == BTF_KIND_STRUCT ? "struct" : "union") << ' ' + << (GetName().empty() ? "<anon>" : GetName()); return Name{os.str()}; } -Name Enumeration::MakeDescription(NameCache &names) const { +Name +Enumeration::MakeDescription(NameCache& names) const +{ std::ostringstream os; os << "enum " << (GetName().empty() ? "<anon>" : GetName()); if (GetEnums().empty()) @@ -481,506 +585,606 @@ Name Enumeration::MakeDescription(NameCache &names) const { return Name{os.str()}; } -Name ForwardDeclaration::MakeDescription(NameCache &names) const { +Name +ForwardDeclaration::MakeDescription(NameCache& names) const +{ std::ostringstream os; os << GetFwdKind() << ' ' << GetName() << "<incomplete>"; return Name{os.str()}; } -Name FunctionPrototype::MakeDescription(NameCache &names) const { +Name +FunctionPrototype::MakeDescription(NameCache& names) const +{ std::ostringstream os; os << '('; bool sep = false; - for (const auto &p : GetParameters()) { - if (sep) - os << ", "; - else - sep = true; - const auto &arg_descr = GetTypeAtIndex(p.typeId_).GetDescription(names); - if (p.name_.empty()) - os << arg_descr; - else - os << arg_descr.Add(Side::LEFT, Precedence::ATOMIC, p.name_); - } + for (const auto& p : GetParameters()) + { + if (sep) + os << ", "; + else + sep = true; + const auto& arg_descr = GetTypeAtIndex(p.typeId_).GetDescription(names); + if (p.name_.empty()) + os << arg_descr; + else + os << arg_descr.Add(Side::LEFT, Precedence::ATOMIC, p.name_); + } os << ')'; - return GetTypeAtIndex(GetReturnTypeId()).GetDescription(names).Add( - Side::RIGHT, Precedence::ARRAY_FUNCTION, os.str()); + return GetTypeAtIndex(GetReturnTypeId()) + .GetDescription(names) + .Add(Side::RIGHT, Precedence::ARRAY_FUNCTION, os.str()); } -Name Variable::MakeDescription(NameCache &names) const { - return GetTypeAtIndex(GetVarTypeId()).GetDescription(names).Add( - Side::LEFT, Precedence::ATOMIC, GetName()); +Name +Variable::MakeDescription(NameCache& names) const +{ + return GetTypeAtIndex(GetVarTypeId()) + .GetDescription(names) + .Add(Side::LEFT, Precedence::ATOMIC, GetName()); } -Name Function::MakeDescription(NameCache &names) const { - return GetTypeAtIndex(GetReferredTypeId()).GetDescription(names).Add( - Side::LEFT, Precedence::ATOMIC, GetName()); +Name +Function::MakeDescription(NameCache& names) const +{ + return GetTypeAtIndex(GetReferredTypeId()) + .GetDescription(names) + .Add(Side::LEFT, Precedence::ATOMIC, GetName()); } -Name DataSection::MakeDescription(NameCache &names) const { +Name +DataSection::MakeDescription(NameCache& names) const +{ // NOTE: not yet encountered in the wild return Name{"Unimplemented"}; } -Name ElfSymbol::MakeDescription(NameCache &names) const { +Name +ElfSymbol::MakeDescription(NameCache& names) const +{ return Name{symbol_->get_name()}; } -Result Void::Equals(const Type &other, State &state) const { +Result +Void::Equals(const Type& other, State& state) const +{ return {}; } -Result Ptr::Equals(const Type &other, State &state) const { +Result +Ptr::Equals(const Type& other, State& state) const +{ Result result; - const auto &o = other.as<Ptr>(); + const auto& o = other.as<Ptr>(); const auto ref_diff = Compare(GetTypeAtIndex(GetPointeeTypeId()), - o.GetTypeAtIndex(o.GetPointeeTypeId()), state); + o.GetTypeAtIndex(o.GetPointeeTypeId()), + state); result.MaybeAddDiff("pointed-to type", ref_diff); return result; } -Result Typedef::Equals(const Type &other, State &state) const { - m_assert(false, "should not be called"); // NOLINT +Result +Typedef::Equals(const Type& other, State& state) const +{ + m_assert(false, "should not be called"); // NOLINT return {}; } -Result Qualifier::Equals(const Type &other, State &state) const { - m_assert(false, "should not be called"); // NOLINT +Result +Qualifier::Equals(const Type& other, State& state) const +{ + m_assert(false, "should not be called"); // NOLINT return {}; } -Result Integer::Equals(const Type &other, State &state) const { +Result +Integer::Equals(const Type& other, State& state) const +{ Result result; - const auto &o = other.as<Integer>(); + const auto& o = other.as<Integer>(); - if (isBool() != o.isBool()) { - result.AddDiff(isBool() ? "the first one is a boolean" - : "the second one is a boolean"); - } - if (isSigned() != o.isSigned()) { - result.AddDiff(isSigned() ? "the first one is signed" - : "the second one is signed"); - } - if (isChar() != o.isChar()) { - result.AddDiff(isChar() ? "the first one is a char" - : "the second one is a char"); - } + if (isBool() != o.isBool()) + { + result.AddDiff(isBool() ? "the first one is a boolean" + : "the second one is a boolean"); + } + if (isSigned() != o.isSigned()) + { + result.AddDiff(isSigned() ? "the first one is signed" + : "the second one is signed"); + } + if (isChar() != o.isChar()) + { + result.AddDiff(isChar() ? "the first one is a char" + : "the second one is a char"); + } result.MaybeAddDiff("offset", GetOffset(), o.GetOffset()); result.MaybeAddDiff("bit size", GetBitSize(), o.GetBitSize()); - if (GetBitSize() != GetByteSize() * 8 && - o.GetBitSize() != o.GetByteSize() * 8) + if (GetBitSize() != GetByteSize() * 8 + && o.GetBitSize() != o.GetByteSize() * 8) result.MaybeAddDiff("byte size", GetByteSize(), o.GetByteSize()); return result; } -Result Array::Equals(const Type &other, State &state) const { +Result +Array::Equals(const Type& other, State& state) const +{ Result result; - const auto &o = other.as<Array>(); + const auto& o = other.as<Array>(); - result.MaybeAddDiff("number of elements", - GetNumberOfElements(), o.GetNumberOfElements()); - const auto index_type_diff = - Compare(GetTypeAtIndex(GetIndexTypeId()), - o.GetTypeAtIndex(o.GetIndexTypeId()), state); + result.MaybeAddDiff( + "number of elements", GetNumberOfElements(), o.GetNumberOfElements()); + const auto index_type_diff = Compare(GetTypeAtIndex(GetIndexTypeId()), + o.GetTypeAtIndex(o.GetIndexTypeId()), + state); result.MaybeAddDiff("index type", index_type_diff); const auto element_type_diff = Compare(GetTypeAtIndex(GetElementTypeId()), - o.GetTypeAtIndex(o.GetElementTypeId()), state); + o.GetTypeAtIndex(o.GetElementTypeId()), + state); result.MaybeAddDiff("element type", element_type_diff); return result; } -Result StructUnion::Equals(const Type &other, State &state) const { +Result +StructUnion::Equals(const Type& other, State& state) const +{ Result result; - const auto &o = other.as<StructUnion>(); + const auto& o = other.as<StructUnion>(); - if (GetKind() != o.GetKind()) { - result.AddDiff(GetKind() == BTF_KIND_STRUCT - ? "changed from struct to union" - : "changed from union to struct"); - } + if (GetKind() != o.GetKind()) + { + result.AddDiff(GetKind() == BTF_KIND_STRUCT + ? "changed from struct to union" + : "changed from union to struct"); + } result.MaybeAddDiff("byte size", GetByteSize(), o.GetByteSize()); - const auto &members1 = GetMembers(); - const auto &members2 = o.GetMembers(); + const auto& members1 = GetMembers(); + const auto& members2 = o.GetMembers(); std::set<std::string> visited_members; - for (const auto &m1 : members1) { - visited_members.insert(m1.first); - auto iter = members2.find(m1.first); - if (iter == members2.end()) { - std::ostringstream os; - os << "member " << std::quoted(m1.first) << " of type"; - auto diff = Removed(GetTypeAtIndex(m1.second.typeId_), state); - result.AddDiff(os.str(), diff); - } else { - result.MaybeAddDiff([&](std::ostream &os) { - os << "member " << std::quoted(m1.first) << " offset"; - }, m1.second.offset_, iter->second.offset_); - result.MaybeAddDiff([&](std::ostream &os) { - os << "member " << std::quoted(m1.first) << " bitfield size"; - }, m1.second.bitfieldSize_, iter->second.bitfieldSize_); - const auto sub_diff = - Compare(GetTypeAtIndex(m1.second.typeId_), - o.GetTypeAtIndex(iter->second.typeId_), state); - result.MaybeAddDiff([&](std::ostream &os) { - os << "member " << std::quoted(m1.first) << " type"; - }, sub_diff); + for (const auto& m1 : members1) + { + visited_members.insert(m1.first); + auto iter = members2.find(m1.first); + if (iter == members2.end()) + { + std::ostringstream os; + os << "member " << std::quoted(m1.first) << " of type"; + auto diff = Removed(GetTypeAtIndex(m1.second.typeId_), state); + result.AddDiff(os.str(), diff); + } + else + { + result.MaybeAddDiff( + [&](std::ostream& os) { + os << "member " << std::quoted(m1.first) << " offset"; + }, + m1.second.offset_, + iter->second.offset_); + result.MaybeAddDiff( + [&](std::ostream& os) { + os << "member " << std::quoted(m1.first) << " bitfield size"; + }, + m1.second.bitfieldSize_, + iter->second.bitfieldSize_); + const auto sub_diff = Compare(GetTypeAtIndex(m1.second.typeId_), + o.GetTypeAtIndex(iter->second.typeId_), + state); + result.MaybeAddDiff( + [&](std::ostream& os) { + os << "member " << std::quoted(m1.first) << " type"; + }, + sub_diff); + } } - } - for (const auto &m2 : members2) { - if (visited_members.find(m2.first) == visited_members.end()) { - std::ostringstream os; - os << "member " << std::quoted(m2.first) << " of type"; - auto diff = Added(o.GetTypeAtIndex(m2.second.typeId_), state); - result.AddDiff(os.str(), diff); + for (const auto& m2 : members2) + { + if (visited_members.find(m2.first) == visited_members.end()) + { + std::ostringstream os; + os << "member " << std::quoted(m2.first) << " of type"; + auto diff = Added(o.GetTypeAtIndex(m2.second.typeId_), state); + result.AddDiff(os.str(), diff); + } } - } return result; } -Result Enumeration::Equals(const Type &other, State &state) const { +Result +Enumeration::Equals(const Type& other, State& state) const +{ Result result; - const auto &o = other.as<Enumeration>(); + const auto& o = other.as<Enumeration>(); result.MaybeAddDiff("byte size", GetByteSize(), o.GetByteSize()); - const auto &enums1 = GetEnums(); - const auto &enums2 = o.GetEnums(); + const auto& enums1 = GetEnums(); + const auto& enums2 = o.GetEnums(); std::set<std::string> visited_enums; - for (const auto &e1 : enums1) { - visited_enums.insert(e1.first); - auto iter = enums2.find(e1.first); - if (iter == enums2.end()) { - std::ostringstream os; - os << "enumerator " << std::quoted(e1.first) - << " (" << e1.second << ") was removed"; - result.AddDiff(os.str()); - } else { - result.MaybeAddDiff([&](std::ostream &os) { - os << "enumerator " << std::quoted(e1.first) << " value"; - }, e1.second, iter->second); + for (const auto& e1 : enums1) + { + visited_enums.insert(e1.first); + auto iter = enums2.find(e1.first); + if (iter == enums2.end()) + { + std::ostringstream os; + os << "enumerator " << std::quoted(e1.first) << " (" << e1.second + << ") was removed"; + result.AddDiff(os.str()); + } + else + { + result.MaybeAddDiff( + [&](std::ostream& os) { + os << "enumerator " << std::quoted(e1.first) << " value"; + }, + e1.second, + iter->second); + } } - } - for (const auto &e2 : enums2) { - if (visited_enums.find(e2.first) == visited_enums.end()) { - std::ostringstream os; - os << "enumerator " << std::quoted(e2.first) - << " (" << e2.second << ") was added"; - result.AddDiff(os.str()); + for (const auto& e2 : enums2) + { + if (visited_enums.find(e2.first) == visited_enums.end()) + { + std::ostringstream os; + os << "enumerator " << std::quoted(e2.first) << " (" << e2.second + << ") was added"; + result.AddDiff(os.str()); + } } - } return result; } -Result ForwardDeclaration::Equals(const Type &other, State &state) const { +Result +ForwardDeclaration::Equals(const Type& other, State& state) const +{ Result result; - const auto &o = other.as<ForwardDeclaration>(); + const auto& o = other.as<ForwardDeclaration>(); result.MaybeAddDiff("kind", GetFwdKind(), o.GetFwdKind()); return result; } -Result Function::Equals(const Type &other, State &state) const { +Result +Function::Equals(const Type& other, State& state) const +{ Result result; - const auto &o = other.as<Function>(); + const auto& o = other.as<Function>(); result.MaybeAddDiff("linkage", GetLinkage(), o.GetLinkage()); - const auto func_proto_diff = - Compare(GetTypeAtIndex(GetReferredTypeId()), - o.GetTypeAtIndex(o.GetReferredTypeId()), state); + const auto func_proto_diff = Compare(GetTypeAtIndex(GetReferredTypeId()), + o.GetTypeAtIndex(o.GetReferredTypeId()), + state); result.MaybeAddDiff("type", func_proto_diff); return result; } -Result FunctionPrototype::Equals(const Type &other, State &state) const { +Result +FunctionPrototype::Equals(const Type& other, State& state) const +{ Result result; - const auto &o = other.as<FunctionPrototype>(); + const auto& o = other.as<FunctionPrototype>(); - const auto return_type_diff = - Compare(GetTypeAtIndex(GetReturnTypeId()), - o.GetTypeAtIndex(o.GetReturnTypeId()), state); + const auto return_type_diff = Compare(GetTypeAtIndex(GetReturnTypeId()), + o.GetTypeAtIndex(o.GetReturnTypeId()), + state); result.MaybeAddDiff("return type", return_type_diff); - const auto ¶meters1 = GetParameters(); - const auto ¶meters2 = o.GetParameters(); + const auto& parameters1 = GetParameters(); + const auto& parameters2 = o.GetParameters(); size_t min = std::min(parameters1.size(), parameters2.size()); - for (size_t i = 0; i < min; ++i) { - const auto &p1 = parameters1.at(i); - const auto &p2 = parameters2.at(i); - const auto sub_diff = Compare(GetTypeAtIndex(p1.typeId_), - o.GetTypeAtIndex(p2.typeId_), state); - result.MaybeAddDiff([&](std::ostream &os) { - os << "parameter " << i + 1; - const auto &n1 = p1.name_; - const auto &n2 = p2.name_; - if (n1 == n2 && !n1.empty()) { - os << " (" << std::quoted(n1) << ")"; - } else if (n1 != n2) { - os << " ("; - if (!n1.empty()) os << "was " << std::quoted(n1); - if (!n1.empty() && !n2.empty()) os << ", "; - if (!n2.empty()) os << "now " << std::quoted(n2); - os << ")"; - } - os << " type"; - }, sub_diff); - } + for (size_t i = 0; i < min; ++i) + { + const auto& p1 = parameters1.at(i); + const auto& p2 = parameters2.at(i); + const auto sub_diff = Compare( + GetTypeAtIndex(p1.typeId_), o.GetTypeAtIndex(p2.typeId_), state); + result.MaybeAddDiff( + [&](std::ostream& os) { + os << "parameter " << i + 1; + const auto& n1 = p1.name_; + const auto& n2 = p2.name_; + if (n1 == n2 && !n1.empty()) + { + os << " (" << std::quoted(n1) << ")"; + } + else if (n1 != n2) + { + os << " ("; + if (!n1.empty()) + os << "was " << std::quoted(n1); + if (!n1.empty() && !n2.empty()) + os << ", "; + if (!n2.empty()) + os << "now " << std::quoted(n2); + os << ")"; + } + os << " type"; + }, + sub_diff); + } bool added = parameters1.size() < parameters2.size(); - const auto ¶meters = added ? parameters2 : parameters1; - for (size_t i = min; i < parameters.size(); ++i) { - const auto ¶meter = parameters.at(i); - std::ostringstream os; - os << "parameter " << i + 1; - if (!parameter.name_.empty()) - os << " (" << std::quoted(parameter.name_) << ")"; - os << " of type"; - const auto ¶meter_type = GetTypeAtIndex(parameter.typeId_); - auto diff = added ? Added(parameter_type, state) - : Removed(parameter_type, state); - result.AddDiff(os.str(), diff); - } + const auto& parameters = added ? parameters2 : parameters1; + for (size_t i = min; i < parameters.size(); ++i) + { + const auto& parameter = parameters.at(i); + std::ostringstream os; + os << "parameter " << i + 1; + if (!parameter.name_.empty()) + os << " (" << std::quoted(parameter.name_) << ")"; + os << " of type"; + const auto& parameter_type = GetTypeAtIndex(parameter.typeId_); + auto diff = added ? Added(parameter_type, state) + : Removed(parameter_type, state); + result.AddDiff(os.str(), diff); + } return result; } // NOTE: not yet encountered in the wild -Result Variable::Equals(const Type &other, State &state) const { +Result +Variable::Equals(const Type& other, State& state) const +{ Result result; - const auto &o = other.as<Variable>(); + const auto& o = other.as<Variable>(); result.MaybeAddDiff("linkage", GetLinkage(), o.GetLinkage()); const auto var_diff = Compare(GetTypeAtIndex(GetVarTypeId()), - o.GetTypeAtIndex(o.GetVarTypeId()), state); + o.GetTypeAtIndex(o.GetVarTypeId()), + state); result.MaybeAddDiff("type", var_diff); return result; } -Result DataSection::Equals(const Type &other, State &state) const { +Result +DataSection::Equals(const Type& other, State& state) const +{ Result result; result.AddDiff("Unimplemented"); // NOTE: not yet encountered in the wild - m_assert(false, "Unimplemented\n"); // NOLINT + m_assert(false, "Unimplemented\n"); // NOLINT return result; } -Result ElfSymbol::Equals(const Type &other, State &state) const { +Result +ElfSymbol::Equals(const Type& other, State& state) const +{ Result result; - const auto &o = other.as<ElfSymbol>(); + const auto& o = other.as<ElfSymbol>(); // TODO: compare ELF symbol attributes - const auto type_diff = Compare(GetTypeAtIndex(type_id_), - o.GetTypeAtIndex(o.type_id_), state); + const auto type_diff = + Compare(GetTypeAtIndex(type_id_), o.GetTypeAtIndex(o.type_id_), state); result.MaybeAddDiff("type", type_diff); return result; } -const Type &Type::ResolveQualifiers(std::set<Kind> &qualifiers) const { - if (kind_ == BTF_KIND_ARRAY || kind_ == BTF_KIND_FUNC_PROTO) { - // There should be no qualifiers here. - qualifiers.clear(); - } +const Type& +Type::ResolveQualifiers(std::set<Kind>& qualifiers) const +{ + if (kind_ == BTF_KIND_ARRAY || kind_ == BTF_KIND_FUNC_PROTO) + { + // There should be no qualifiers here. + qualifiers.clear(); + } return *this; } -const Type &Qualifier::ResolveQualifiers( - std::set<Kind> &qualifiers) const { +const Type& +Qualifier::ResolveQualifiers(std::set<Kind>& qualifiers) const +{ qualifiers.insert(GetKind()); return GetTypeAtIndex(GetQualifiedTypeId()).ResolveQualifiers(qualifiers); } -const Type &Type::ResolveTypedef( - std::vector<std::string> &typedefs) const { +const Type& +Type::ResolveTypedef(std::vector<std::string>& typedefs) const +{ return *this; } -const Type &Typedef::ResolveTypedef( - std::vector<std::string> &typedefs) const { +const Type& +Typedef::ResolveTypedef(std::vector<std::string>& typedefs) const +{ typedefs.push_back(GetName()); return GetTypeAtIndex(GetReferredTypeId()).ResolveTypedef(typedefs); } static constexpr std::string_view ANON{"(anon)"}; -std::ostream &operator<<(std::ostream &os, const Ptr &bp) { - os << kRawKindNames[bp.GetKind()] - << " '" << ANON << "'" - << " type_id=" << bp.GetPointeeTypeId() - << '\n'; +std::ostream& +operator<<(std::ostream& os, const Ptr& bp) +{ + os << kRawKindNames[bp.GetKind()] << " '" << ANON << "'" + << " type_id=" << bp.GetPointeeTypeId() << '\n'; return os; } -std::ostream &operator<<(std::ostream &os, const Typedef &bp) { - os << kRawKindNames[bp.GetKind()] - << " '" << bp.GetName() << "'" - << " type_id=" << bp.GetReferredTypeId() - << '\n'; +std::ostream& +operator<<(std::ostream& os, const Typedef& bp) +{ + os << kRawKindNames[bp.GetKind()] << " '" << bp.GetName() << "'" + << " type_id=" << bp.GetReferredTypeId() << '\n'; return os; } -std::ostream &operator<<(std::ostream &os, const Qualifier &bp) { - os << kRawKindNames[bp.GetKind()] - << " '" << ANON << "'" - << " type_id=" << bp.GetQualifiedTypeId() - << '\n'; +std::ostream& +operator<<(std::ostream& os, const Qualifier& bp) +{ + os << kRawKindNames[bp.GetKind()] << " '" << ANON << "'" + << " type_id=" << bp.GetQualifiedTypeId() << '\n'; return os; } -std::ostream &operator<<(std::ostream &os, const Integer &bi) { - os << kRawKindNames[bi.GetKind()] - << " '" << bi.GetName() << "'" - << " size=" << bi.GetByteSize() - << " bits_offset=" << bi.GetOffset() - << " nr_bits=" << bi.GetBitSize() - << " bool=" << bi.isBool() - << " char=" << bi.isChar() - << " signed=" << bi.isSigned() - << '\n'; +std::ostream& +operator<<(std::ostream& os, const Integer& bi) +{ + os << kRawKindNames[bi.GetKind()] << " '" << bi.GetName() << "'" + << " size=" << bi.GetByteSize() << " bits_offset=" << bi.GetOffset() + << " nr_bits=" << bi.GetBitSize() << " bool=" << bi.isBool() + << " char=" << bi.isChar() << " signed=" << bi.isSigned() << '\n'; return os; } -std::ostream &operator<<(std::ostream &os, const Array &ba) { - os << kRawKindNames[ba.GetKind()] - << " '" << ANON << "'" +std::ostream& +operator<<(std::ostream& os, const Array& ba) +{ + os << kRawKindNames[ba.GetKind()] << " '" << ANON << "'" << " type_id=" << ba.GetElementTypeId() << " index_type_id=" << ba.GetIndexTypeId() - << " nr_elems=" << ba.GetNumberOfElements() - << '\n'; + << " nr_elems=" << ba.GetNumberOfElements() << '\n'; return os; } -std::ostream &operator<<(std::ostream &os, const StructUnion &bsu) { - const auto &name = bsu.GetName(); - os << kRawKindNames[bsu.GetKind()] - << " '" << (name.empty() ? ANON : name) << "'" - << " size=" << bsu.GetByteSize() - << " vlen=" << bsu.GetMembers().size() << '\n'; - for (const auto &member : bsu.GetMembers()) { - os << "\t'" << member.first << '\'' - << " type_id=" << member.second.typeId_ - << " bits_offset=" << member.second.offset_; - if (member.second.bitfieldSize_) - os << " bitfield_size=" << member.second.bitfieldSize_; - os << '\n'; - } +std::ostream& +operator<<(std::ostream& os, const StructUnion& bsu) +{ + const auto& name = bsu.GetName(); + os << kRawKindNames[bsu.GetKind()] << " '" << (name.empty() ? ANON : name) + << "'" + << " size=" << bsu.GetByteSize() << " vlen=" << bsu.GetMembers().size() + << '\n'; + for (const auto& member : bsu.GetMembers()) + { + os << "\t'" << member.first << '\'' + << " type_id=" << member.second.typeId_ + << " bits_offset=" << member.second.offset_; + if (member.second.bitfieldSize_) + os << " bitfield_size=" << member.second.bitfieldSize_; + os << '\n'; + } return os; } -std::ostream &operator<<(std::ostream &os, const Enumeration &be) { - const auto &name = be.GetName(); - os << kRawKindNames[be.GetKind()] - << " '" << (name.empty() ? ANON : name) << "'" - << " size=" << be.GetByteSize() - << " vlen=" << be.GetEnums().size() +std::ostream& +operator<<(std::ostream& os, const Enumeration& be) +{ + const auto& name = be.GetName(); + os << kRawKindNames[be.GetKind()] << " '" << (name.empty() ? ANON : name) + << "'" + << " size=" << be.GetByteSize() << " vlen=" << be.GetEnums().size() << '\n'; - for (const auto &e : be.GetEnums()) { - os << "\t'" << e.first << "' val=" << e.second << '\n'; - } + for (const auto& e : be.GetEnums()) + { + os << "\t'" << e.first << "' val=" << e.second << '\n'; + } return os; } -std::ostream &operator<<(std::ostream &os, const ForwardDeclaration &bfd) { - os << kRawKindNames[bfd.GetKind()] - << " '" << bfd.GetName() << "'" - << " fwd_kind=" << bfd.GetFwdKind() - << '\n'; +std::ostream& +operator<<(std::ostream& os, const ForwardDeclaration& bfd) +{ + os << kRawKindNames[bfd.GetKind()] << " '" << bfd.GetName() << "'" + << " fwd_kind=" << bfd.GetFwdKind() << '\n'; return os; } -std::ostream &operator<<(std::ostream &os, const Function &bf) { - os << kRawKindNames[bf.GetKind()] - << " '" << bf.GetName() << "'" - << " type_id=" << bf.GetReferredTypeId() - << " linkage=" << bf.GetLinkage() +std::ostream& +operator<<(std::ostream& os, const Function& bf) +{ + os << kRawKindNames[bf.GetKind()] << " '" << bf.GetName() << "'" + << " type_id=" << bf.GetReferredTypeId() << " linkage=" << bf.GetLinkage() << '\n'; return os; } -std::ostream &operator<<(std::ostream &os, const FunctionPrototype &bfp) { - os << kRawKindNames[bfp.GetKind()] - << " '" << ANON << "'" +std::ostream& +operator<<(std::ostream& os, const FunctionPrototype& bfp) +{ + os << kRawKindNames[bfp.GetKind()] << " '" << ANON << "'" << " ret_type_id=" << bfp.GetReturnTypeId() - << " vlen=" << bfp.GetParameters().size() - << '\n'; - for (const auto ¶m : bfp.GetParameters()) { - os << "\t'" << (param.name_.empty() ? ANON : param.name_) - << "' type_id=" << param.typeId_ << '\n'; - } + << " vlen=" << bfp.GetParameters().size() << '\n'; + for (const auto& param : bfp.GetParameters()) + { + os << "\t'" << (param.name_.empty() ? ANON : param.name_) + << "' type_id=" << param.typeId_ << '\n'; + } return os; } -std::ostream &operator<<(std::ostream &os, const Variable &bv) { +std::ostream& +operator<<(std::ostream& os, const Variable& bv) +{ // NOTE: The odd comma is to match bpftool dump. - os << kRawKindNames[bv.GetKind()] - << " type_id=" << bv.GetVarTypeId() - << ", linkage=" << bv.GetLinkage() - << '\n'; + os << kRawKindNames[bv.GetKind()] << " type_id=" << bv.GetVarTypeId() + << ", linkage=" << bv.GetLinkage() << '\n'; return os; } -std::ostream &operator<<(std::ostream &os, const DataSection &bds) { - os << kRawKindNames[bds.GetKind()] - << " size=" << bds.GetByteSize() - << '\n'; - for (const auto &secinfo : bds.GetSecinfos()) { - os << "\ttype_id=" << secinfo.typeId_ - << " offset=" << secinfo.offset_ - << " size=" << secinfo.bytesize_ << '\n'; - } +std::ostream& +operator<<(std::ostream& os, const DataSection& bds) +{ + os << kRawKindNames[bds.GetKind()] << " size=" << bds.GetByteSize() << '\n'; + for (const auto& secinfo : bds.GetSecinfos()) + { + os << "\ttype_id=" << secinfo.typeId_ << " offset=" << secinfo.offset_ + << " size=" << secinfo.bytesize_ << '\n'; + } return os; } -std::ostream &operator<<(std::ostream &os, const ElfSymbol &bes) { +std::ostream& +operator<<(std::ostream& os, const ElfSymbol& bes) +{ os << kRawKindNames[bes.GetKind()]; // TODO: report ELF symbol attributes - os << " type=" << bes.GetTypeId() - << '\n'; + os << " type=" << bes.GetTypeId() << '\n'; return os; } -std::ostream &operator<<(std::ostream &os, ForwardDeclarationKind kind) { - switch (kind) { +std::ostream& +operator<<(std::ostream& os, ForwardDeclarationKind kind) +{ + switch (kind) + { case ForwardDeclarationKind::STRUCT: os << "struct"; break; case ForwardDeclarationKind::UNION: os << "union"; break; - } + } return os; } -std::ostream &operator<<(std::ostream &os, Variable::Linkage linkage) { +std::ostream& +operator<<(std::ostream& os, Variable::Linkage linkage) +{ auto ix = static_cast<size_t>(linkage); return os << (ix < kVarLinkage.size() ? kVarLinkage[ix] : "(unknown)"); } -std::ostream &operator<<(std::ostream &os, Function::Linkage linkage) { +std::ostream& +operator<<(std::ostream& os, Function::Linkage linkage) +{ auto ix = static_cast<size_t>(linkage); return os << (ix < kFunLinkage.size() ? kFunLinkage[ix] : "(unknown)"); } -Structs::Structs(const char *start, - std::unique_ptr<abigail::ir::environment> env, - const abigail::symtab_reader::symtab_sptr tab, - const bool verbose) - : env_(std::move(env)), - tab_(tab), - verbose_(verbose) { - header_ = reinterpret_cast<const btf_header *>(start); +Structs::Structs(const char* start, + std::unique_ptr<abigail::ir::environment> env, + const abigail::symtab_reader::symtab_sptr tab, + const bool verbose) + : env_(std::move(env)), tab_(tab), verbose_(verbose) +{ + header_ = reinterpret_cast<const btf_header*>(start); m_assert(header_->magic == 0xEB9F, "Magic field must be 0xEB9F for BTF"); - type_section_ = reinterpret_cast<const btf_type *>(start + header_->hdr_len + - header_->type_off); + type_section_ = reinterpret_cast<const btf_type*>(start + header_->hdr_len + + header_->type_off); str_section_ = start + header_->hdr_len + header_->str_off; // every btf_type struct in the type section has an implicit type id. @@ -989,13 +1193,15 @@ Structs::Structs(const char *start, // recognized type starting from id 1. types_.push_back(std::make_unique<Void>(types_, 0, 0)); - if (verbose_) { - PrintHeader(); - } + if (verbose_) + { + PrintHeader(); + } BuildTypes(); - if (verbose_) { - PrintStringSection(); - } + if (verbose_) + { + PrintStringSection(); + } // NOTE: a whole bunch of Linux kernel symbols appear with duplicate (but not // necessarily identical) BTF type information @@ -1003,361 +1209,436 @@ Structs::Structs(const char *start, // TODO: find a better way of resolving this bad_prefix_1_ = "__arm64_sys_"; bad_prefix_2_ = "__arm64_compat_sys_"; - bad_names_ = { - "arch_prctl_spec_ctrl_get", - "arch_prctl_spec_ctrl_set", - "ioremap_cache", - "kvm_arch_set_irq_inatomic", - "module_frob_arch_sections", - "vsnprintf" - }; + bad_names_ = {"arch_prctl_spec_ctrl_get", + "arch_prctl_spec_ctrl_set", + "ioremap_cache", + "kvm_arch_set_irq_inatomic", + "module_frob_arch_sections", + "vsnprintf"}; } -void Structs::PrintHeader() { +void +Structs::PrintHeader() +{ std::cout << "BTF header:\n" - << "\tmagic " << header_->magic - << ", version " << static_cast<int>(header_->version) - << ", flags " << static_cast<int>(header_->flags) - << ", hdr_len " << header_->hdr_len << "\n" - << "\ttype_off " << header_->type_off - << ", type_len " << header_->type_len << "\n" - << "\tstr_off " << header_->str_off - << ", str_len " << header_->str_len << "\n"; + << "\tmagic " << header_->magic << ", version " + << static_cast<int>(header_->version) << ", flags " + << static_cast<int>(header_->flags) << ", hdr_len " + << header_->hdr_len << "\n" + << "\ttype_off " << header_->type_off << ", type_len " + << header_->type_len << "\n" + << "\tstr_off " << header_->str_off << ", str_len " + << header_->str_len << "\n"; } // vlen: vector length, the number of struct/union members -std::map<std::string, Member> Structs::BuildMembers( - bool kflag, const btf_member *members, size_t vlen) { +std::map<std::string, Member> +Structs::BuildMembers(bool kflag, const btf_member* members, size_t vlen) +{ std::map<std::string, Member> result; int anonymous = 0; - for (size_t i = 0; i < vlen; ++i) { - const auto raw_offset = members[i].offset; - Member member{ - .typeId_ = members[i].type, - .offset_ = kflag ? BTF_MEMBER_BIT_OFFSET(raw_offset) : raw_offset, - .bitfieldSize_ = kflag ? BTF_MEMBER_BITFIELD_SIZE(raw_offset) : 0}; - std::string name = std::string(GetName(members[i].name_off)); - if (name.empty()) { - name = "anon member #" + std::to_string(anonymous); - ++anonymous; + for (size_t i = 0; i < vlen; ++i) + { + const auto raw_offset = members[i].offset; + Member member{ + .typeId_ = members[i].type, + .offset_ = kflag ? BTF_MEMBER_BIT_OFFSET(raw_offset) : raw_offset, + .bitfieldSize_ = kflag ? BTF_MEMBER_BITFIELD_SIZE(raw_offset) : 0}; + std::string name = std::string(GetName(members[i].name_off)); + if (name.empty()) + { + name = "anon member #" + std::to_string(anonymous); + ++anonymous; + } + result.emplace(name, member); } - result.emplace(name, member); - } return result; } // vlen: vector length, the number of enum values -std::map<std::string, int> Structs::BuildEnums(const struct btf_enum *enums, - size_t vlen) { +std::map<std::string, int> +Structs::BuildEnums(const struct btf_enum* enums, size_t vlen) +{ std::map<std::string, int> result; - for (size_t i = 0; i < vlen; ++i) { - result.emplace(std::string(GetName(enums[i].name_off)), enums[i].val); - } + for (size_t i = 0; i < vlen; ++i) + { + result.emplace(std::string(GetName(enums[i].name_off)), enums[i].val); + } return result; } // vlen: vector length, the number of parameters -std::vector<Parameter> Structs::BuildParams(const struct btf_param *params, - size_t vlen) { +std::vector<Parameter> +Structs::BuildParams(const struct btf_param* params, size_t vlen) +{ std::vector<Parameter> result; result.reserve(vlen); - for (size_t i = 0; i < vlen; ++i) { - Parameter parameter{ - .name_ = std::string(GetName(params[i].name_off)), - .typeId_ = params[i].type}; - result.push_back(parameter); - } + for (size_t i = 0; i < vlen; ++i) + { + Parameter parameter{.name_ = std::string(GetName(params[i].name_off)), + .typeId_ = params[i].type}; + result.push_back(parameter); + } return result; } // vlen: vector length, the number of variables -std::vector<Secinfo> Structs::BuildDatasec(const btf_type *type, - size_t vlen) { +std::vector<Secinfo> +Structs::BuildDatasec(const btf_type* type, size_t vlen) +{ std::vector<Secinfo> result; result.reserve(vlen); - const auto *secinfos = reinterpret_cast<const btf_var_secinfo *>(type + 1); - for (size_t i = 0; i < vlen; ++i) { - Secinfo secinfo{.typeId_ = secinfos[i].type, - .offset_ = secinfos[i].offset, - .bytesize_ = secinfos[i].size}; - result.push_back(secinfo); - } + const auto* secinfos = reinterpret_cast<const btf_var_secinfo*>(type + 1); + for (size_t i = 0; i < vlen; ++i) + { + Secinfo secinfo{.typeId_ = secinfos[i].type, + .offset_ = secinfos[i].offset, + .bytesize_ = secinfos[i].size}; + result.push_back(secinfo); + } return result; } -void Structs::BuildTypes() { - m_assert(!(header_->type_off & (sizeof(uint32_t) - 1)), "Unaligned type_off"); - if (header_->type_len == 0) { - std::cerr << "No types found"; - return; - } - if (verbose_) { - std::cout << "Type section:\n"; - } +void +Structs::BuildTypes() +{ + m_assert(!(header_->type_off & (sizeof(uint32_t) - 1)), + "Unaligned type_off"); + if (header_->type_len == 0) + { + std::cerr << "No types found"; + return; + } + if (verbose_) + { + std::cout << "Type section:\n"; + } - const char *curr = reinterpret_cast<const char *>(type_section_); - const char *end = curr + header_->type_len; + const char* curr = reinterpret_cast<const char*>(type_section_); + const char* end = curr + header_->type_len; uint32_t index = 1; - while (curr < end) { - const btf_type *t = reinterpret_cast<const btf_type *>(curr); - int type_size = BuildOneType(t, index); - m_assert(type_size > 0, "Could not identify BTF type"); - curr += type_size; - ++index; - } + while (curr < end) + { + const btf_type* t = reinterpret_cast<const btf_type*>(curr); + int type_size = BuildOneType(t, index); + m_assert(type_size > 0, "Could not identify BTF type"); + curr += type_size; + ++index; + } BuildElfSymbols(); } -int Structs::BuildOneType(const btf_type *t, uint32_t index) { +int +Structs::BuildOneType(const btf_type* t, uint32_t index) +{ const auto kind = BTF_INFO_KIND(t->info); const auto vlen = BTF_INFO_VLEN(t->info); // Data following the btf_type struct. - const void *data = reinterpret_cast<const void *>(t + 1); + const void* data = reinterpret_cast<const void*>(t + 1); m_assert(kind >= 0 && kind < NR_BTF_KINDS, "Unknown BTF kind"); - if (verbose_) std::cout << '[' << index << "] "; + if (verbose_) + std::cout << '[' << index << "] "; int type_size = sizeof(struct btf_type); - switch (kind) { - case BTF_KIND_INT: { - const auto bits = *reinterpret_cast<const uint32_t *>(data); - types_.push_back(std::make_unique<Integer>( - types_, index, GetName(t->name_off), kind, - BTF_INT_ENCODING(bits), BTF_INT_OFFSET(bits), BTF_INT_BITS(bits), - t->size)); - if (verbose_) { - std::cout << types_.back()->as<Integer>(); + switch (kind) + { + case BTF_KIND_INT: + { + const auto bits = *reinterpret_cast<const uint32_t*>(data); + types_.push_back(std::make_unique<Integer>(types_, + index, + GetName(t->name_off), + kind, + BTF_INT_ENCODING(bits), + BTF_INT_OFFSET(bits), + BTF_INT_BITS(bits), + t->size)); + if (verbose_) + { + std::cout << types_.back()->as<Integer>(); + } + type_size += sizeof(uint32_t); + break; } - type_size += sizeof(uint32_t); - break; - } - case BTF_KIND_PTR: { - types_.push_back(std::make_unique<Ptr>(types_, index, kind, t->type)); - if (verbose_) { - std::cout << types_.back()->as<Ptr>(); + case BTF_KIND_PTR: + { + types_.push_back(std::make_unique<Ptr>(types_, index, kind, t->type)); + if (verbose_) + { + std::cout << types_.back()->as<Ptr>(); + } + break; } - break; - } - case BTF_KIND_TYPEDEF: { - types_.push_back(std::make_unique<Typedef>( - types_, index, GetName(t->name_off), kind, t->type)); - if (verbose_) { - std::cout << types_.back()->as<Typedef>(); + case BTF_KIND_TYPEDEF: + { + types_.push_back(std::make_unique<Typedef>( + types_, index, GetName(t->name_off), kind, t->type)); + if (verbose_) + { + std::cout << types_.back()->as<Typedef>(); + } + break; } - break; - } case BTF_KIND_VOLATILE: case BTF_KIND_CONST: - case BTF_KIND_RESTRICT: { - types_.push_back(std::make_unique<Qualifier>( - types_, index, kind, t->type)); - if (verbose_) { - std::cout << types_.back()->as<Qualifier>(); + case BTF_KIND_RESTRICT: + { + types_.push_back( + std::make_unique<Qualifier>(types_, index, kind, t->type)); + if (verbose_) + { + std::cout << types_.back()->as<Qualifier>(); + } + break; } - break; - } - case BTF_KIND_ARRAY: { - const auto *array = reinterpret_cast<const struct btf_array *>(data); - types_.push_back(std::make_unique<Array>( - types_, index, kind, array->type, array->index_type, array->nelems)); - if (verbose_) { - std::cout << types_.back()->as<Array>(); + case BTF_KIND_ARRAY: + { + const auto* array = reinterpret_cast<const struct btf_array*>(data); + types_.push_back(std::make_unique<Array>(types_, + index, + kind, + array->type, + array->index_type, + array->nelems)); + if (verbose_) + { + std::cout << types_.back()->as<Array>(); + } + type_size += sizeof(struct btf_array); + break; } - type_size += sizeof(struct btf_array); - break; - } case BTF_KIND_STRUCT: - case BTF_KIND_UNION: { - const bool kflag = BTF_INFO_KFLAG(t->info); - const auto *btf_members = reinterpret_cast<const btf_member *>(data); - const auto members = BuildMembers(kflag, btf_members, vlen); - types_.push_back(std::make_unique<StructUnion>( - types_, index, GetName(t->name_off), kind, t->size, members)); - if (verbose_) { - std::cout << types_.back()->as<StructUnion>(); + case BTF_KIND_UNION: + { + const bool kflag = BTF_INFO_KFLAG(t->info); + const auto* btf_members = reinterpret_cast<const btf_member*>(data); + const auto members = BuildMembers(kflag, btf_members, vlen); + types_.push_back(std::make_unique<StructUnion>( + types_, index, GetName(t->name_off), kind, t->size, members)); + if (verbose_) + { + std::cout << types_.back()->as<StructUnion>(); + } + type_size += vlen * sizeof(struct btf_member); + break; } - type_size += vlen * sizeof(struct btf_member); - break; - } - case BTF_KIND_ENUM: { - const auto *enums = reinterpret_cast<const struct btf_enum *>(data); - std::map<std::string, int> enumerators = BuildEnums(enums, vlen); - types_.push_back(std::make_unique<Enumeration>( - types_, index, GetName(t->name_off), kind, - t->size, enumerators)); - if (verbose_) { - std::cout << types_.back()->as<Enumeration>(); + case BTF_KIND_ENUM: + { + const auto* enums = reinterpret_cast<const struct btf_enum*>(data); + std::map<std::string, int> enumerators = BuildEnums(enums, vlen); + types_.push_back(std::make_unique<Enumeration>( + types_, index, GetName(t->name_off), kind, t->size, enumerators)); + if (verbose_) + { + std::cout << types_.back()->as<Enumeration>(); + } + type_size += vlen * sizeof(struct btf_enum); + break; } - type_size += vlen * sizeof(struct btf_enum); - break; - } - case BTF_KIND_FWD: { - const bool kflag = BTF_INFO_KFLAG(t->info); - types_.push_back(std::make_unique<ForwardDeclaration>( - types_, index, GetName(t->name_off), kind, kflag)); - if (verbose_) { - std::cout << types_.back()->as<ForwardDeclaration>(); + case BTF_KIND_FWD: + { + const bool kflag = BTF_INFO_KFLAG(t->info); + types_.push_back(std::make_unique<ForwardDeclaration>( + types_, index, GetName(t->name_off), kind, kflag)); + if (verbose_) + { + std::cout << types_.back()->as<ForwardDeclaration>(); + } + break; } - break; - } - case BTF_KIND_FUNC: { - const auto name = GetName(t->name_off); - types_.push_back(std::make_unique<Function>( - types_, index, name, kind, t->type, - Function::Linkage(vlen))); - if (verbose_) { - std::cout << types_.back()->as<Function>(); + case BTF_KIND_FUNC: + { + const auto name = GetName(t->name_off); + types_.push_back(std::make_unique<Function>( + types_, index, name, kind, t->type, Function::Linkage(vlen))); + if (verbose_) + { + std::cout << types_.back()->as<Function>(); + } + bool inserted = btf_symbol_types_.insert({name, t->type}).second; + if (!inserted) + { + // NOTE: duplicate BTF symbols could be considered a bug in pahole + // + // TODO: remove these checks once resolved + bool known = + !name.compare(0, bad_prefix_1_.size(), bad_prefix_1_) + || !name.compare(0, bad_prefix_2_.size(), bad_prefix_2_) + || std::find(bad_names_.begin(), bad_names_.end(), name) + != bad_names_.end(); + m_assert(known, "Insertion failed, duplicate found in symbol map"); + (void) known; + } + btf_symbols_.insert({name, types_.back().get()}); + break; } - bool inserted = btf_symbol_types_.insert({name, t->type}).second; - if (!inserted) { - // NOTE: duplicate BTF symbols could be considered a bug in pahole - // - // TODO: remove these checks once resolved - bool known = !name.compare(0, bad_prefix_1_.size(), bad_prefix_1_) || - !name.compare(0, bad_prefix_2_.size(), bad_prefix_2_) || - std::find(bad_names_.begin(), bad_names_.end(), name) != - bad_names_.end(); - m_assert(known, "Insertion failed, duplicate found in symbol map"); - (void)known; + case BTF_KIND_FUNC_PROTO: + { + const auto* params = reinterpret_cast<const btf_param*>(data); + std::vector<Parameter> parameters = BuildParams(params, vlen); + types_.push_back(std::make_unique<FunctionPrototype>( + types_, index, kind, t->type, parameters)); + if (verbose_) + { + std::cout << types_.back()->as<FunctionPrototype>(); + } + type_size += vlen * sizeof(struct btf_param); + break; } - btf_symbols_.insert({name, types_.back().get()}); - break; - } - case BTF_KIND_FUNC_PROTO: { - const auto *params = reinterpret_cast<const btf_param *>(data); - std::vector<Parameter> parameters = BuildParams(params, vlen); - types_.push_back(std::make_unique<FunctionPrototype>( - types_, index, kind, t->type, parameters)); - if (verbose_) { - std::cout << types_.back()->as<FunctionPrototype>(); + case BTF_KIND_VAR: + { + // NOTE: not yet encountered in the wild + const auto* variable = reinterpret_cast<const struct btf_var*>(data); + const auto name = GetName(t->name_off); + types_.push_back( + std::make_unique<Variable>(types_, + index, + name, + kind, + t->type, + Variable::Linkage(variable->linkage))); + if (verbose_) + { + std::cout << types_.back()->as<Variable>(); + } + + bool inserted = btf_symbol_types_.insert({name, t->type}).second; + m_assert(inserted, "Insertion failed, duplicate found in symbol map"); + (void) inserted; + btf_symbols_.insert({name, types_.back().get()}); + + type_size += sizeof(struct btf_var); + break; } - type_size += vlen * sizeof(struct btf_param); - break; - } - case BTF_KIND_VAR: { - // NOTE: not yet encountered in the wild - const auto *variable = reinterpret_cast<const struct btf_var *>(data); - const auto name = GetName(t->name_off); - types_.push_back(std::make_unique<Variable>( - types_, index, name, kind, t->type, - Variable::Linkage(variable->linkage))); - if (verbose_) { - std::cout << types_.back()->as<Variable>(); + case BTF_KIND_DATASEC: + { + std::vector<Secinfo> secinfos = BuildDatasec(t, vlen); + types_.push_back(std::make_unique<DataSection>( + types_, index, kind, t->size, secinfos)); + if (verbose_) + { + std::cout << types_.back()->as<DataSection>(); + } + type_size += vlen * sizeof(struct btf_var_secinfo); } - - bool inserted = btf_symbol_types_.insert({name, t->type}).second; - m_assert(inserted, "Insertion failed, duplicate found in symbol map"); - (void)inserted; - btf_symbols_.insert({name, types_.back().get()}); - - type_size += sizeof(struct btf_var); - break; - } - case BTF_KIND_DATASEC: { - std::vector<Secinfo> secinfos = BuildDatasec(t, vlen); - types_.push_back(std::make_unique<DataSection>( - types_, index, kind, t->size, secinfos)); - if (verbose_) { - std::cout << types_.back()->as<DataSection>(); - } - type_size += vlen * sizeof(struct btf_var_secinfo); } - } return type_size; } -std::string Structs::GetName(uint32_t name_off) { +std::string +Structs::GetName(uint32_t name_off) +{ m_assert(name_off < header_->str_len, - "The name offset exceeds the section length"); - const char *section_end = str_section_ + header_->str_len; - const char *name_begin = str_section_ + name_off; - const char *name_end = std::find(name_begin, section_end, '\0'); + "The name offset exceeds the section length"); + const char* section_end = str_section_ + header_->str_len; + const char* name_begin = str_section_ + name_off; + const char* name_end = std::find(name_begin, section_end, '\0'); m_assert(name_end < section_end, - "The name continues past the string section limit"); + "The name continues past the string section limit"); return {name_begin, static_cast<size_t>(name_end - name_begin)}; } -void Structs::PrintStringSection() { +void +Structs::PrintStringSection() +{ std::cout << "String section:\n"; - const char *curr = str_section_; - const char *limit = str_section_ + header_->str_len; - while (curr < limit) { - const char *pos = std::find(curr, limit, '\0'); - m_assert(pos < limit, "Error reading the string section"); - std::cout << ' ' << curr; - curr = pos + 1; - } + const char* curr = str_section_; + const char* limit = str_section_ + header_->str_len; + while (curr < limit) + { + const char* pos = std::find(curr, limit, '\0'); + m_assert(pos < limit, "Error reading the string section"); + std::cout << ' ' << curr; + curr = pos + 1; + } std::cout << '\n'; } -void Structs::BuildElfSymbols() { +void +Structs::BuildElfSymbols() +{ const auto filter = [&]() { auto filter = tab_->make_filter(); filter.set_public_symbols(); return filter; }(); - for (const auto &symbol : - abigail::symtab_reader::filtered_symtab(*tab_, filter)) { - const auto &symbol_name = symbol->get_name(); - const auto &main_symbol_name = symbol->get_main_symbol()->get_name(); - auto it = btf_symbol_types_.find(main_symbol_name); - if (it == btf_symbol_types_.end()) { - // missing BTF information is tracked explicitly - std::cerr << "ELF symbol " << std::quoted(symbol_name); - if (symbol_name != main_symbol_name) - std::cerr << " (aliased to " << std::quoted(main_symbol_name) << ')'; - std::cerr << " BTF info missing\n"; - types_.push_back(nullptr); - } else { - uint32_t type_id = it->second; - types_.push_back(std::make_unique<ElfSymbol>(types_, symbol, type_id)); + for (const auto& symbol : + abigail::symtab_reader::filtered_symtab(*tab_, filter)) + { + const auto& symbol_name = symbol->get_name(); + const auto& main_symbol_name = symbol->get_main_symbol()->get_name(); + auto it = btf_symbol_types_.find(main_symbol_name); + if (it == btf_symbol_types_.end()) + { + // missing BTF information is tracked explicitly + std::cerr << "ELF symbol " << std::quoted(symbol_name); + if (symbol_name != main_symbol_name) + std::cerr << " (aliased to " << std::quoted(main_symbol_name) + << ')'; + std::cerr << " BTF info missing\n"; + types_.push_back(nullptr); + } + else + { + uint32_t type_id = it->second; + types_.push_back( + std::make_unique<ElfSymbol>(types_, symbol, type_id)); + } + elf_symbols_.emplace(symbol_name, types_.back().get()); } - elf_symbols_.emplace(symbol_name, types_.back().get()); - } } -class ElfHandle { - public: - ElfHandle(const std::string &path) : dwfl_(nullptr, dwfl_end) { +class ElfHandle +{ +public: + ElfHandle(const std::string& path) : dwfl_(nullptr, dwfl_end) + { string name; tools_utils::base_name(path, name); elf_version(EV_CURRENT); dwfl_ = std::unique_ptr<Dwfl, decltype(&dwfl_end)>( - dwfl_begin(&offline_callbacks_), dwfl_end); - auto dwfl_module = dwfl_report_offline(dwfl_.get(), name.c_str(), - path.c_str(), -1); + dwfl_begin(&offline_callbacks_), dwfl_end); + auto dwfl_module = + dwfl_report_offline(dwfl_.get(), name.c_str(), path.c_str(), -1); GElf_Addr bias; elf_handle_ = dwfl_module_getelf(dwfl_module, &bias); } // Conversion operator to act as a drop-in replacement for Elf* - operator Elf *() const { return elf_handle_; } + operator Elf*() const { return elf_handle_; } - Elf *get() const { return elf_handle_; } + Elf* + get() const + { + return elf_handle_; + } - private: +private: // Dwfl owns all our data, hence only keep track of this std::unique_ptr<Dwfl, decltype(&dwfl_end)> dwfl_; - Elf *elf_handle_; + Elf* elf_handle_; Dwfl_Callbacks offline_callbacks_; }; -Structs ReadFile(const std::string &path, bool verbose) { +Structs +ReadFile(const std::string& path, bool verbose) +{ using abigail::symtab_reader::symtab; ElfHandle elf(path); m_assert(elf.get() != nullptr, "Could not get elf handle from file."); - Elf_Scn *btf_section = + Elf_Scn* btf_section = abigail::elf_helpers::find_section(elf, ".BTF", SHT_PROGBITS); m_assert(btf_section != nullptr, - "The given file does not have a BTF section"); - Elf_Data *elf_data = elf_rawdata(btf_section, 0); + "The given file does not have a BTF section"); + Elf_Data* elf_data = elf_rawdata(btf_section, 0); m_assert(elf_data != nullptr, "The BTF section is invalid"); - const char *btf_start = static_cast<char *>(elf_data->d_buf); + const char* btf_start = static_cast<char*>(elf_data->d_buf); auto env = std::make_unique<abigail::ir::environment>(); auto tab = symtab::load(elf, env.get()); @@ -1365,5 +1646,5 @@ Structs ReadFile(const std::string &path, bool verbose) { return Structs(btf_start, std::move(env), std::move(tab), verbose); } -} // end namespace btf -} // end namespace abigail +} // end namespace btf +} // end namespace abigail diff --git a/tests/test-scc.cc b/tests/test-scc.cc index a75b1ae0..62e840a1 100644 --- a/tests/test-scc.cc +++ b/tests/test-scc.cc @@ -19,83 +19,109 @@ #include "abg-scc.h" -namespace Test { +namespace Test +{ using abigail::SCC; // Nodes are [0, N), the sets are the out-edges. typedef std::vector<std::set<size_t>> Graph; -std::ostream &operator<<(std::ostream &os, const Graph &g) { - for (size_t i = 0; i < g.size(); ++i) { - os << i << ':'; - for (auto o : g[i]) - os << ' ' << o; - os << '\n'; - } +std::ostream& +operator<<(std::ostream& os, const Graph& g) +{ + for (size_t i = 0; i < g.size(); ++i) + { + os << i << ':'; + for (auto o : g[i]) + os << ' ' << o; + os << '\n'; + } return os; } -template<typename G> Graph invent(size_t n, G& gen) { +template <typename G> +Graph +invent(size_t n, G& gen) +{ Graph graph(n); std::uniform_int_distribution<int> toss(0, 1); - for (auto &node : graph) { - for (size_t o = 0; o < n; ++o) { - if (toss(gen)) - node.insert(o); + for (auto& node : graph) + { + for (size_t o = 0; o < n; ++o) + { + if (toss(gen)) + node.insert(o); + } } - } return graph; } // Generate a graph g' where a -> b iff a and b are strongly connected in g. -Graph symmetric_subset_of_reflexive_transitive_closure(Graph g) { +Graph +symmetric_subset_of_reflexive_transitive_closure(Graph g) +{ const size_t n = g.size(); // transitive closure using Floyd-Warshall for (size_t o = 0; o < n; ++o) g[o].insert(o); - for (size_t k = 0; k < n; ++k) { - for (size_t i = 0; i < n; ++i) { - for (size_t j = 0; j < n; ++j) { - if (!g[i].count(j) && g[i].count(k) && g[k].count(j)) - g[i].insert(j); - } + for (size_t k = 0; k < n; ++k) + { + for (size_t i = 0; i < n; ++i) + { + for (size_t j = 0; j < n; ++j) + { + if (!g[i].count(j) && g[i].count(k) && g[k].count(j)) + g[i].insert(j); + } + } } - } // now a -> b iff a has path to b in g - for (size_t i = 0; i < n; ++i) { - for (size_t j = i + 1; j < n; ++j) { - // discard a -> b if not b -> a and vice versa - auto ij = g[i].count(j); - auto ji = g[j].count(i); - if (ij < ji) g[j].erase(i); - if (ji < ij) g[i].erase(j); + for (size_t i = 0; i < n; ++i) + { + for (size_t j = i + 1; j < n; ++j) + { + // discard a -> b if not b -> a and vice versa + auto ij = g[i].count(j); + auto ji = g[j].count(i); + if (ij < ji) + g[j].erase(i); + if (ji < ij) + g[i].erase(j); + } } - } // now have a -> b iff a has path to b and b has path to a in g return g; } // Generate a graph where a -> b iff a and b are in the same SCC. -Graph scc_strong_connectivity(const std::vector<std::set<size_t>> &sccs) { +Graph +scc_strong_connectivity(const std::vector<std::set<size_t>>& sccs) +{ size_t n = 0; - std::map<size_t, const std::set<size_t> *> edges; - for (const auto &scc : sccs) { - for (auto o : scc) { - if (o >= n) - n = o + 1; - edges[o] = &scc; + std::map<size_t, const std::set<size_t>*> edges; + for (const auto& scc : sccs) + { + for (auto o : scc) + { + if (o >= n) + n = o + 1; + edges[o] = &scc; + } } - } Graph g(n); for (size_t o = 0; o < n; ++o) g[o] = *edges[o]; return g; } -void dfs(std::set<size_t> &visited, SCC<size_t> &scc, - const Graph &g, size_t node, - std::vector<std::set<size_t>> &sccs) { +void +dfs(std::set<size_t>& visited, + SCC<size_t>& scc, + const Graph& g, + size_t node, + std::vector<std::set<size_t>>& sccs) +{ if (visited.count(node)) return; auto handle = scc.Open(node); @@ -104,17 +130,21 @@ void dfs(std::set<size_t> &visited, SCC<size_t> &scc, for (auto o : g[node]) dfs(visited, scc, g, o, sccs); auto nodes = scc.Close(handle.value()); - if (!nodes.empty()) { - std::set<size_t> scc_set; - for (auto o : nodes) { - CHECK(visited.insert(o).second); - CHECK(scc_set.insert(o).second); + if (!nodes.empty()) + { + std::set<size_t> scc_set; + for (auto o : nodes) + { + CHECK(visited.insert(o).second); + CHECK(scc_set.insert(o).second); + } + sccs.push_back(scc_set); } - sccs.push_back(scc_set); - } } -void process(const Graph &g) { +void +process(const Graph& g) +{ const size_t n = g.size(); // find SCCs @@ -126,21 +156,25 @@ void process(const Graph &g) { // check partition and topological order properties std::set<size_t> seen; - for (const auto &nodes : sccs) { - CHECK(!nodes.empty()); - for (auto node : nodes) { - // value in range [0, n) - CHECK(node < n); - // value seen at most once - CHECK(seen.insert(node).second); - } - for (auto node : nodes) { - for (auto o : g[node]) { - // edges point to nodes in this or earlier SCCs - CHECK(seen.count(o)); - } + for (const auto& nodes : sccs) + { + CHECK(!nodes.empty()); + for (auto node : nodes) + { + // value in range [0, n) + CHECK(node < n); + // value seen at most once + CHECK(seen.insert(node).second); + } + for (auto node : nodes) + { + for (auto o : g[node]) + { + // edges point to nodes in this or earlier SCCs + CHECK(seen.count(o)); + } + } } - } // exactly n values seen CHECK(seen.size() == n); @@ -148,15 +182,18 @@ void process(const Graph &g) { auto g_scc_closure = scc_strong_connectivity(sccs); auto g_closure = symmetric_subset_of_reflexive_transitive_closure(g); // catch isn't printing nicely - if (g_scc_closure != g_closure) { - std::cerr << "original:\n" << g - << "SCC finder:\n" << g_scc_closure - << "SCCs independently:\n" << g_closure; - } + if (g_scc_closure != g_closure) + { + std::cerr << "original:\n" + << g << "SCC finder:\n" + << g_scc_closure << "SCCs independently:\n" + << g_closure; + } CHECK(g_scc_closure == g_closure); } -TEST_CASE("randomly-generated graphs") { +TEST_CASE("randomly-generated graphs") +{ std::mt19937 gen; auto seed = gen(); // NOTES: @@ -164,20 +201,20 @@ TEST_CASE("randomly-generated graphs") { // There are O(2^k^2) possible directed graphs of size k. // Testing costs are O(k^3) so we restrict accordingly. uint64_t budget = 10000; - for (size_t k = 0; k < 7; ++k) { - uint64_t count = std::min(static_cast<uint64_t>(1) << (k*k), - budget / (k ? k * k * k : 1)); - INFO("testing with " << count << " graphs of size " << k); - for (uint64_t n = 0; n < count; ++n, ++seed) { - gen.seed(seed); - Graph g = invent(k, gen); - std::ostringstream os; - os << "a graph of " << k << " nodes generated using seed " << seed; - GIVEN(os.str()) { - process(g); - } + for (size_t k = 0; k < 7; ++k) + { + uint64_t count = std::min(static_cast<uint64_t>(1) << (k * k), + budget / (k ? k * k * k : 1)); + INFO("testing with " << count << " graphs of size " << k); + for (uint64_t n = 0; n < count; ++n, ++seed) + { + gen.seed(seed); + Graph g = invent(k, gen); + std::ostringstream os; + os << "a graph of " << k << " nodes generated using seed " << seed; + GIVEN(os.str()) { process(g); } + } } - } } -} // namespace Test +} // namespace Test diff --git a/tools/btfdiff.cc b/tools/btfdiff.cc index 0649821d..c90dc4c9 100644 --- a/tools/btfdiff.cc +++ b/tools/btfdiff.cc @@ -16,48 +16,51 @@ const int kAbiChange = 4; -int main(int argc, char *argv[]) { +int +main(int argc, char* argv[]) +{ bool use_elf_symbols = true; static option opts[] = { - { "symbols", required_argument, nullptr, 's' }, - { nullptr, 0, nullptr, 0 }, + {"symbols", required_argument, nullptr, 's'}, + {nullptr, 0, nullptr, 0}, }; auto usage = [&]() { - std::cerr << "usage: " << argv[0] - << " [-s|--symbols type] file1 file2\n" - << " where type is elf (the default) or btf\n"; + std::cerr << "usage: " << argv[0] << " [-s|--symbols type] file1 file2\n" + << " where type is elf (the default) or btf\n"; return 1; }; auto bad_arg = [&](int ix) { std::cerr << argv[0] << ": option '--" << opts[ix].name - << "' unrecognized argument '" << optarg << "'\n"; + << "' unrecognized argument '" << optarg << "'\n"; return usage(); }; - while (true) { - int ix; - int c = getopt_long(argc, argv, "s:", opts, &ix); - if (c == -1) - break; - switch (c) { - case 's': - if (!strcmp(optarg, "btf")) - use_elf_symbols = false; - else if (!strcmp(optarg, "elf")) - use_elf_symbols = true; - else - return bad_arg(ix); - break; - default: - return usage(); + while (true) + { + int ix; + int c = getopt_long(argc, argv, "s:", opts, &ix); + if (c == -1) + break; + switch (c) + { + case 's': + if (!strcmp(optarg, "btf")) + use_elf_symbols = false; + else if (!strcmp(optarg, "elf")) + use_elf_symbols = true; + else + return bad_arg(ix); + break; + default: + return usage(); + } } - } if (optind + 2 != argc) return usage(); const auto structs1 = abigail::btf::ReadFile(argv[optind++]); const auto structs2 = abigail::btf::ReadFile(argv[optind++]); - const auto &map1 = structs1.GetSymbols(use_elf_symbols); - const auto &map2 = structs2.GetSymbols(use_elf_symbols); + const auto& map1 = structs1.GetSymbols(use_elf_symbols); + const auto& map2 = structs2.GetSymbols(use_elf_symbols); abigail::btf::Outcomes outcomes; auto result = abigail::btf::Type::CompareSymbols(map1, map2, outcomes); abigail::btf::NameCache names; diff --git a/tools/btfinfo.cc b/tools/btfinfo.cc index dbda7945..8b40cc96 100644 --- a/tools/btfinfo.cc +++ b/tools/btfinfo.cc @@ -7,11 +7,14 @@ #include "abg-btf.h" -int main(int argc, const char *argv[]) { - if (argc != 2) { - std::cerr << "Please specify the path to a BTF file."; - return 1; - } +int +main(int argc, const char* argv[]) +{ + if (argc != 2) + { + std::cerr << "Please specify the path to a BTF file."; + return 1; + } (void) abigail::btf::ReadFile(argv[1], /* verbose = */ true); -- 2.32.0.288.g62a8d224e6-goog ^ permalink raw reply [flat|nested] 14+ messages in thread
end of thread, other threads:[~2021-06-22 10:33 UTC | newest] Thread overview: 14+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2021-06-11 15:33 [PATCH 0/6] BTF ABI Giuliano Procida 2021-06-11 15:33 ` [PATCH 1/6] Tweak clang-format Giuliano Procida 2021-06-11 15:33 ` [PATCH 2/6] Allow C++17 code to be compiled Giuliano Procida 2021-06-11 15:33 ` [PATCH 3/6] BTF: add SCC finder and test Giuliano Procida 2021-06-11 15:33 ` [PATCH 4/6] BTF: add core functionality Giuliano Procida 2021-06-11 15:33 ` [PATCH 5/6] BTF: add btfinfo and btfdiff tools Giuliano Procida 2021-06-11 15:33 ` [PATCH 6/6] BTF: clang-format all the new source files Giuliano Procida 2021-06-22 10:33 ` [PATCH v2 0/6] BTF ABI Giuliano Procida 2021-06-22 10:33 ` [PATCH v2 1/6] Allow C++17 code to be compiled Giuliano Procida 2021-06-22 10:33 ` [PATCH v2 2/6] Tweak clang-format Giuliano Procida 2021-06-22 10:33 ` [PATCH v2 3/6] BTF: add SCC finder and test Giuliano Procida 2021-06-22 10:33 ` [PATCH v2 4/6] BTF: add core functionality Giuliano Procida 2021-06-22 10:33 ` [PATCH v2 5/6] BTF: add btfinfo and btfdiff tools Giuliano Procida 2021-06-22 10:33 ` [PATCH v2 6/6] BTF: clang-format all the new source files Giuliano Procida
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