* [committed 1/3] libstdc++: Simplify filesystem::path SFINAE constraints
2020-05-23 8:40 [committed 0/3] libstdc++: Refactor filesystem::path string conversions Jonathan Wakely
@ 2020-05-23 8:42 ` Jonathan Wakely
2020-05-23 8:43 ` [committed 2/3] libstdc++: Remove incorrect static specifiers Jonathan Wakely
2020-05-23 8:44 ` [committed 3/3] libstdc++: Refactor filesystem::path string conversions Jonathan Wakely
2 siblings, 0 replies; 5+ messages in thread
From: Jonathan Wakely @ 2020-05-23 8:42 UTC (permalink / raw)
To: libstdc++, gcc-patches
[-- Attachment #1: Type: text/plain, Size: 1809 bytes --]
This replaces the filesystem::__detail::_Path SFINAE helper with two
separate helpers, _Path and _Path2. This avoids having one helper which
tries to check two different sets of requirements.
The _Path helper now uses variable templates instead of a set of
overloaded functions to detect specializations of basic_string or
basic_string_view.
The __not_<is_void<remove_pointer_t<_Tp1>> check is not necessary in
C++20 because iterator_traits<void*> is now empty. For C++17 replace
that check with a __safe_iterator_traits helper with partial
specializations for void pointers.
Finally, the __is_encoded_char check no longer uses remove_const_t,
which means that iterators with a const value_type will no longer be
accepted as arguments for path creation. Such iterators resulted in
undefined behaviour anyway, so it's still conforming to reject them in
the constraint checks.
* include/bits/fs_path.h (filesystem::__detail::__is_encoded_char):
Replace alias template with variable template. Don't remove const.
(filesystem::__detail::__is_path_src): Replace overloaded function
template with variable template and specializations.
(filesystem::__detail::__is_path_iter_src): Replace alias template
with class template.
(filesystem::__detail::_Path): Use __is_path_src. Remove support for
iterator pairs.
(filesystem::__detail::_Path2): New alias template for checking
InputIterator requirements.
(filesystem::__detail::__constructible_from): Remove.
(filesystem::path): Replace _Path<Iter, Iter> with _Path2<Iter>.
* testsuite/27_io/filesystem/path/construct/80762.cc: Check with two
constructor arguments of void and void* types.
Tested powerpc64le-linux, committed to master.
[-- Attachment #2: patch.txt --]
[-- Type: text/x-patch, Size: 10405 bytes --]
commit 988b853f9c829742907ae22ac66de56facfc7bc5
Author: Jonathan Wakely <jwakely@redhat.com>
Date: Sat May 23 07:28:40 2020 +0100
libstdc++: Simplify filesystem::path SFINAE constraints
This replaces the filesystem::__detail::_Path SFINAE helper with two
separate helpers, _Path and _Path2. This avoids having one helper which
tries to check two different sets of requirements.
The _Path helper now uses variable templates instead of a set of
overloaded functions to detect specializations of basic_string or
basic_string_view.
The __not_<is_void<remove_pointer_t<_Tp1>> check is not necessary in
C++20 because iterator_traits<void*> is now empty. For C++17 replace
that check with a __safe_iterator_traits helper with partial
specializations for void pointers.
Finally, the __is_encoded_char check no longer uses remove_const_t,
which means that iterators with a const value_type will no longer be
accepted as arguments for path creation. Such iterators resulted in
undefined behaviour anyway, so it's still conforming to reject them in
the constraint checks.
* include/bits/fs_path.h (filesystem::__detail::__is_encoded_char):
Replace alias template with variable template. Don't remove const.
(filesystem::__detail::__is_path_src): Replace overloaded function
template with variable template and specializations.
(filesystem::__detail::__is_path_iter_src): Replace alias template
with class template.
(filesystem::__detail::_Path): Use __is_path_src. Remove support for
iterator pairs.
(filesystem::__detail::_Path2): New alias template for checking
InputIterator requirements.
(filesystem::__detail::__constructible_from): Remove.
(filesystem::path): Replace _Path<Iter, Iter> with _Path2<Iter>.
* testsuite/27_io/filesystem/path/construct/80762.cc: Check with two
constructor arguments of void and void* types.
diff --git a/libstdc++-v3/include/bits/fs_path.h b/libstdc++-v3/include/bits/fs_path.h
index ee6ab15cc4c..5a998284a99 100644
--- a/libstdc++-v3/include/bits/fs_path.h
+++ b/libstdc++-v3/include/bits/fs_path.h
@@ -73,58 +73,87 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
namespace __detail
{
template<typename _CharT>
- using __is_encoded_char = __is_one_of<remove_const_t<_CharT>,
- char,
+ inline constexpr bool __is_encoded_char = false;
+ template<>
+ inline constexpr bool __is_encoded_char<char> = true;
#ifdef _GLIBCXX_USE_CHAR8_T
- char8_t,
+ template<>
+ inline constexpr bool __is_encoded_char<char8_t> = true;
#endif
#if _GLIBCXX_USE_WCHAR_T
- wchar_t,
+ template<>
+ inline constexpr bool __is_encoded_char<wchar_t> = true;
#endif
- char16_t, char32_t>;
-
- template<typename _Iter,
- typename _Iter_traits = std::iterator_traits<_Iter>>
- using __is_path_iter_src
- = __and_<__is_encoded_char<typename _Iter_traits::value_type>,
- std::is_base_of<std::input_iterator_tag,
- typename _Iter_traits::iterator_category>>;
+ template<>
+ inline constexpr bool __is_encoded_char<char16_t> = true;
+ template<>
+ inline constexpr bool __is_encoded_char<char32_t> = true;
+#if __cpp_concepts >= 201907L
template<typename _Iter>
- static __is_path_iter_src<_Iter>
- __is_path_src(_Iter, int);
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- static __is_encoded_char<_CharT>
- __is_path_src(const basic_string<_CharT, _Traits, _Alloc>&, int);
-
- template<typename _CharT, typename _Traits>
- static __is_encoded_char<_CharT>
- __is_path_src(const basic_string_view<_CharT, _Traits>&, int);
-
- template<typename _Unknown>
- static std::false_type
- __is_path_src(const _Unknown&, ...);
-
- template<typename _Tp1, typename _Tp2>
- struct __constructible_from;
-
+ using __safe_iterator_traits = std::iterator_traits<_Iter>;
+#else
template<typename _Iter>
- struct __constructible_from<_Iter, _Iter>
- : __is_path_iter_src<_Iter>
+ struct __safe_iterator_traits : std::iterator_traits<_Iter>
+ { };
+
+ // Protect against ill-formed iterator_traits specializations in C++17
+ template<> struct __safe_iterator_traits<void*> { };
+ template<> struct __safe_iterator_traits<const void*> { };
+ template<> struct __safe_iterator_traits<volatile void*> { };
+ template<> struct __safe_iterator_traits<const volatile void*> { };
+#endif
+
+ template<typename _Iter_traits, typename = void>
+ struct __is_path_iter_src
+ : false_type
+ { };
+
+ template<typename _Iter_traits>
+ struct __is_path_iter_src<_Iter_traits,
+ void_t<typename _Iter_traits::value_type>>
+ : bool_constant<__is_encoded_char<typename _Iter_traits::value_type>>
{ };
template<typename _Source>
- struct __constructible_from<_Source, void>
- : decltype(__is_path_src(std::declval<_Source>(), 0))
- { };
+ inline constexpr bool __is_path_src
+ = __is_path_iter_src<iterator_traits<decay_t<_Source>>>::value;
- template<typename _Tp1, typename _Tp2 = void>
- using _Path = typename
- std::enable_if<__and_<__not_<is_same<remove_cv_t<_Tp1>, path>>,
- __not_<is_void<remove_pointer_t<_Tp1>>>,
- __constructible_from<_Tp1, _Tp2>>::value,
- path>::type;
+ template<>
+ inline constexpr bool __is_path_src<path> = false;
+
+ template<>
+ inline constexpr bool __is_path_src<volatile path> = false;
+
+ template<>
+ inline constexpr bool __is_path_src<void*> = false;
+
+ template<>
+ inline constexpr bool __is_path_src<const void*> = false;
+
+ template<>
+ inline constexpr bool __is_path_src<volatile void*> = false;
+
+ template<>
+ inline constexpr bool __is_path_src<const volatile void*> = false;
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ inline constexpr bool
+ __is_path_src<basic_string<_CharT, _Traits, _Alloc>>
+ = __is_encoded_char<_CharT>;
+
+ template<typename _CharT, typename _Traits>
+ inline constexpr bool
+ __is_path_src<basic_string_view<_CharT, _Traits>>
+ = __is_encoded_char<_CharT>;
+
+ // SFINAE constraint for Source parameters as required by [fs.path.req].
+ template<typename _Tp>
+ using _Path = enable_if_t<__is_path_src<_Tp>, path>;
+
+ // SFINAE constraint for InputIterator parameters as required by [fs.req].
+ template<typename _Iter, typename _Tr = __safe_iterator_traits<_Iter>>
+ using _Path2 = enable_if_t<__is_path_iter_src<_Tr>::value, path>;
template<typename _Source>
static _Source
@@ -227,7 +256,7 @@ namespace __detail
{ _M_split_cmpts(); }
template<typename _InputIterator,
- typename _Require = __detail::_Path<_InputIterator, _InputIterator>>
+ typename _Require = __detail::_Path2<_InputIterator>>
path(_InputIterator __first, _InputIterator __last, format = auto_format)
: _M_pathname(_S_convert(__first, __last))
{ _M_split_cmpts(); }
@@ -241,8 +270,8 @@ namespace __detail
{ _M_split_cmpts(); }
template<typename _InputIterator,
- typename _Require = __detail::_Path<_InputIterator, _InputIterator>,
- typename _Require2 = __detail::__value_type_is_char<_InputIterator>>
+ typename _Require = __detail::_Path2<_InputIterator>,
+ typename _Req2 = __detail::__value_type_is_char<_InputIterator>>
path(_InputIterator __first, _InputIterator __last, const locale& __loc,
format = auto_format)
: _M_pathname(_S_convert_loc(__first, __last, __loc))
@@ -268,7 +297,7 @@ namespace __detail
{ return *this = path(__source); }
template<typename _InputIterator>
- __detail::_Path<_InputIterator, _InputIterator>&
+ __detail::_Path2<_InputIterator>&
assign(_InputIterator __first, _InputIterator __last)
{ return *this = path(__first, __last); }
@@ -295,7 +324,7 @@ namespace __detail
}
template<typename _InputIterator>
- __detail::_Path<_InputIterator, _InputIterator>&
+ __detail::_Path2<_InputIterator>&
append(_InputIterator __first, _InputIterator __last)
{
_M_append(_S_convert(__first, __last));
@@ -315,7 +344,7 @@ namespace __detail
operator+=(_Source const& __x) { return concat(__x); }
template<typename _CharT>
- __detail::_Path<_CharT*, _CharT*>&
+ __detail::_Path2<_CharT*>&
operator+=(_CharT __x);
template<typename _Source>
@@ -328,7 +357,7 @@ namespace __detail
}
template<typename _InputIterator>
- __detail::_Path<_InputIterator, _InputIterator>&
+ __detail::_Path2<_InputIterator>&
concat(_InputIterator __first, _InputIterator __last)
{
_M_concat(_S_convert(__first, __last));
@@ -695,7 +724,7 @@ namespace __detail
* @relates std::filesystem::path
*/
template<typename _InputIterator,
- typename _Require = __detail::_Path<_InputIterator, _InputIterator>,
+ typename _Require = __detail::_Path2<_InputIterator>,
typename _CharT
= __detail::__value_type_is_char_or_char8_t<_InputIterator>>
inline path
@@ -1000,7 +1029,7 @@ namespace __detail
}
template<typename _CharT>
- inline __detail::_Path<_CharT*, _CharT*>&
+ inline __detail::_Path2<_CharT*>&
path::operator+=(_CharT __x)
{
auto* __addr = std::__addressof(__x);
diff --git a/libstdc++-v3/testsuite/27_io/filesystem/path/construct/80762.cc b/libstdc++-v3/testsuite/27_io/filesystem/path/construct/80762.cc
index bfc1e125e0c..2f37b663f26 100644
--- a/libstdc++-v3/testsuite/27_io/filesystem/path/construct/80762.cc
+++ b/libstdc++-v3/testsuite/27_io/filesystem/path/construct/80762.cc
@@ -37,3 +37,9 @@ static_assert( !std::is_constructible_v<path, const volatile void*> );
static_assert( !std::is_constructible_v<path, void*&> );
static_assert( !std::is_constructible_v<path, void* const&> );
static_assert( !std::is_constructible_v<path, const void* const&> );
+
+static_assert( !std::is_constructible_v<path, void, void> );
+static_assert( !std::is_constructible_v<path, void*, void*> );
+static_assert( !std::is_constructible_v<path, const void*, void*> );
+static_assert( !std::is_constructible_v<path, volatile void*, void*> );
+static_assert( !std::is_constructible_v<path, const volatile void*, void*> );
^ permalink raw reply [flat|nested] 5+ messages in thread* [committed 3/3] libstdc++: Refactor filesystem::path string conversions
2020-05-23 8:40 [committed 0/3] libstdc++: Refactor filesystem::path string conversions Jonathan Wakely
2020-05-23 8:42 ` [committed 1/3] libstdc++: Simplify filesystem::path SFINAE constraints Jonathan Wakely
2020-05-23 8:43 ` [committed 2/3] libstdc++: Remove incorrect static specifiers Jonathan Wakely
@ 2020-05-23 8:44 ` Jonathan Wakely
2020-06-01 23:14 ` Jonathan Wakely
2 siblings, 1 reply; 5+ messages in thread
From: Jonathan Wakely @ 2020-05-23 8:44 UTC (permalink / raw)
To: libstdc++, gcc-patches
[-- Attachment #1: Type: text/plain, Size: 2197 bytes --]
This simplifies the logic of converting Source arguments and pairs of
InputIterator arguments into the native string format. For any input
that is a contiguous range of path::value_type (or char8_t for POSIX)
a string view can be created and the conversion can be done directly,
with no intermediate allocation. Previously some cases created a
basic_string unnecessarily, for example construction from a pair of
path::string_type::iterators, or a pair of non-const value_type*
pointers.
* include/bits/fs_path.h (__detail::_S_range_begin)
(__detail::_S_range_end, path::_S_string_from_iter): Replace with
overloaded function template __detail::__effective_range.
(__detail::__effective_range): New overloaded function template to
create a basic_string or basic_string_view for an effective range.
(__detail::__value_type_is_char): Use __detail::__effective_range.
Do not use remove_const on value type.
(__detail::__value_type_is_char_or_char8_t): Likewise.
(path::path(const Source&, format))
(path::path(const Source&, const locale&))
(path::operator/=(const Source&), path::append(const Source&))
(path::concat(const Source&)): Use __detail::__effective_range.
(path::_S_to_string(InputIterator, InputIterator)): New function
template to create a string view if possible, or string otherwise.
(path::_S_convert): Add overloads that convert a string returned
by __detail::__effective_range. Use if-constexpr to inline conversion
logic from all overloads of _Cvt::_S_convert.
(path::_S_convert_loc): Add overload that converts a string. Use
_S_to_string to avoid allocation when possible.
(path::_Cvt): Remove.
(path::operator+=(CharT)): Remove indirection through path::concat.
* include/experimental/bits/fs_path.h (path::_S_convert_loc): Add
overload for non-const pointers, to avoid constructing a std::string.
* src/c++17/fs_path.cc (path::_S_convert_loc): Replace conditional
compilation with call to _S_convert.
Tested powerpc64le-linux, committed to master.
[-- Attachment #2: patch.txt --]
[-- Type: text/x-patch, Size: 20476 bytes --]
commit 584d52b088f9fcf78704b504c3f1f07e17c1cded
Author: Jonathan Wakely <jwakely@redhat.com>
Date: Sat May 23 09:00:32 2020 +0100
libstdc++: Refactor filesystem::path string conversions
This simplifies the logic of converting Source arguments and pairs of
InputIterator arguments into the native string format. For any input
that is a contiguous range of path::value_type (or char8_t for POSIX)
a string view can be created and the conversion can be done directly,
with no intermediate allocation. Previously some cases created a
basic_string unnecessarily, for example construction from a pair of
path::string_type::iterators, or a pair of non-const value_type*
pointers.
* include/bits/fs_path.h (__detail::_S_range_begin)
(__detail::_S_range_end, path::_S_string_from_iter): Replace with
overloaded function template __detail::__effective_range.
(__detail::__effective_range): New overloaded function template to
create a basic_string or basic_string_view for an effective range.
(__detail::__value_type_is_char): Use __detail::__effective_range.
Do not use remove_const on value type.
(__detail::__value_type_is_char_or_char8_t): Likewise.
(path::path(const Source&, format))
(path::path(const Source&, const locale&))
(path::operator/=(const Source&), path::append(const Source&))
(path::concat(const Source&)): Use __detail::__effective_range.
(path::_S_to_string(InputIterator, InputIterator)): New function
template to create a string view if possible, or string otherwise.
(path::_S_convert): Add overloads that convert a string returned
by __detail::__effective_range. Use if-constexpr to inline conversion
logic from all overloads of _Cvt::_S_convert.
(path::_S_convert_loc): Add overload that converts a string. Use
_S_to_string to avoid allocation when possible.
(path::_Cvt): Remove.
(path::operator+=(CharT)): Remove indirection through path::concat.
* include/experimental/bits/fs_path.h (path::_S_convert_loc): Add
overload for non-const pointers, to avoid constructing a std::string.
* src/c++17/fs_path.cc (path::_S_convert_loc): Replace conditional
compilation with call to _S_convert.
diff --git a/libstdc++-v3/include/bits/fs_path.h b/libstdc++-v3/include/bits/fs_path.h
index 818b5918927..2d2766ec62e 100644
--- a/libstdc++-v3/include/bits/fs_path.h
+++ b/libstdc++-v3/include/bits/fs_path.h
@@ -155,56 +155,61 @@ namespace __detail
template<typename _Iter, typename _Tr = __safe_iterator_traits<_Iter>>
using _Path2 = enable_if_t<__is_path_iter_src<_Tr>::value, path>;
- template<typename _Source>
- _Source
- _S_range_begin(_Source __begin) { return __begin; }
-
- struct __null_terminated { };
-
- template<typename _Source>
- __null_terminated
- _S_range_end(_Source) { return {}; }
+ // The __effective_range overloads convert a Source parameter into
+ // either a basic_string_view or basic_string containing the
+ // effective range of the Source, as defined in [fs.path.req].
template<typename _CharT, typename _Traits, typename _Alloc>
- inline const _CharT*
- _S_range_begin(const basic_string<_CharT, _Traits, _Alloc>& __str)
- { return __str.data(); }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- inline const _CharT*
- _S_range_end(const basic_string<_CharT, _Traits, _Alloc>& __str)
- { return __str.data() + __str.size(); }
+ inline basic_string_view<_CharT, _Traits>
+ __effective_range(const basic_string<_CharT, _Traits, _Alloc>& __source)
+ { return __source; }
template<typename _CharT, typename _Traits>
- inline const _CharT*
- _S_range_begin(const basic_string_view<_CharT, _Traits>& __str)
- { return __str.data(); }
+ inline const basic_string_view<_CharT, _Traits>&
+ __effective_range(const basic_string_view<_CharT, _Traits>& __source)
+ { return __source; }
- template<typename _CharT, typename _Traits>
- inline const _CharT*
- _S_range_end(const basic_string_view<_CharT, _Traits>& __str)
- { return __str.data() + __str.size(); }
+ template<typename _Source>
+ inline auto
+ __effective_range(const _Source& __source)
+ {
+ if constexpr (is_pointer_v<decay_t<_Source>>)
+ return basic_string_view{&*__source};
+ else
+ {
+ // _Source is an input iterator that iterates over an NTCTS.
+ // Create a basic_string by reading until the null character.
+ using value_type
+ = typename iterator_traits<_Source>::value_type;
+ basic_string<value_type> __str;
+ _Source __it = __source;
+ for (value_type __ch = *__it; __ch != value_type(); __ch = *++__it)
+ __str.push_back(__ch);
+ return __str;
+ }
+ }
- template<typename _Tp,
- typename _Iter = decltype(_S_range_begin(std::declval<_Tp>())),
- typename _Val = typename std::iterator_traits<_Iter>::value_type,
- typename _UnqualVal = std::remove_const_t<_Val>>
+ // The value type of a Source parameter's effective range.
+ template<typename _Tp>
+ using __value_t = typename remove_reference_t<
+ decltype(__detail::__effective_range(std::declval<_Tp>()))>::value_type;
+
+ // SFINAE helper to check that an effective range has value_type char,
+ // as required by path constructors taking a std::locale parameter.
+ // The type _Tp must have already been checked by _Path<Tp> or _Path2<_Tp>.
+ template<typename _Tp, typename _Val = __value_t<_Tp>>
using __value_type_is_char
- = std::enable_if_t<std::is_same_v<_UnqualVal, char>,
- _UnqualVal>;
+ = std::enable_if_t<std::is_same_v<_Val, char>, _Val>;
- template<typename _Tp,
- typename _Iter = decltype(_S_range_begin(std::declval<_Tp>())),
- typename _Val = typename std::iterator_traits<_Iter>::value_type,
- typename _UnqualVal = std::remove_const_t<_Val>>
+ // As above, but also allows char8_t, as required by u8path
+ // C++20 [depr.fs.path.factory]
+ template<typename _Tp, typename _Val = __value_t<_Tp>>
using __value_type_is_char_or_char8_t
- = std::enable_if_t<__or_v<
- std::is_same<_UnqualVal, char>
+ = std::enable_if_t<std::is_same_v<_Val, char>
#ifdef _GLIBCXX_USE_CHAR8_T
- , std::is_same<_UnqualVal, char8_t>
+ || std::is_same_v<_Val, char8_t>
#endif
- >,
- _UnqualVal>;
+ , _Val>;
} // namespace __detail
/// @endcond
@@ -251,8 +256,7 @@ namespace __detail
template<typename _Source,
typename _Require = __detail::_Path<_Source>>
path(_Source const& __source, format = auto_format)
- : _M_pathname(_S_convert(__detail::_S_range_begin(__source),
- __detail::_S_range_end(__source)))
+ : _M_pathname(_S_convert(__detail::__effective_range(__source)))
{ _M_split_cmpts(); }
template<typename _InputIterator,
@@ -264,9 +268,8 @@ namespace __detail
template<typename _Source,
typename _Require = __detail::_Path<_Source>,
typename _Require2 = __detail::__value_type_is_char<_Source>>
- path(_Source const& __source, const locale& __loc, format = auto_format)
- : _M_pathname(_S_convert_loc(__detail::_S_range_begin(__source),
- __detail::_S_range_end(__source), __loc))
+ path(_Source const& __src, const locale& __loc, format = auto_format)
+ : _M_pathname(_S_convert_loc(__detail::__effective_range(__src), __loc))
{ _M_split_cmpts(); }
template<typename _InputIterator,
@@ -309,8 +312,7 @@ namespace __detail
__detail::_Path<_Source>&
operator/=(_Source const& __source)
{
- _M_append(_S_convert(__detail::_S_range_begin(__source),
- __detail::_S_range_end(__source)));
+ _M_append(_S_convert(__detail::__effective_range(__source)));
return *this;
}
@@ -318,8 +320,7 @@ namespace __detail
__detail::_Path<_Source>&
append(_Source const& __source)
{
- _M_append(_S_convert(__detail::_S_range_begin(__source),
- __detail::_S_range_end(__source)));
+ _M_append(_S_convert(__detail::__effective_range(__source)));
return *this;
}
@@ -351,8 +352,7 @@ namespace __detail
__detail::_Path<_Source>&
concat(_Source const& __x)
{
- _M_concat(_S_convert(__detail::_S_range_begin(__x),
- __detail::_S_range_end(__x)));
+ _M_concat(_S_convert(__detail::__effective_range(__x)));
return *this;
}
@@ -523,22 +523,6 @@ namespace __detail
return __result;
}
- /// @cond undocumented
- // Create a basic_string by reading until a null character.
- template<typename _InputIterator,
- typename _Traits = std::iterator_traits<_InputIterator>,
- typename _CharT
- = typename std::remove_cv_t<typename _Traits::value_type>>
- static std::basic_string<_CharT>
- _S_string_from_iter(_InputIterator __source)
- {
- std::basic_string<_CharT> __str;
- for (_CharT __ch = *__source; __ch != _CharT(); __ch = *++__source)
- __str.push_back(__ch);
- return __str;
- }
- /// @endcond
-
private:
enum class _Type : unsigned char {
_Multi = 0, _Root_name, _Root_dir, _Filename
@@ -558,43 +542,67 @@ namespace __detail
pair<const string_type*, size_t> _M_find_extension() const noexcept;
- template<typename _CharT>
- struct _Cvt;
+ // Create a string or string view from an iterator range.
+ template<typename _InputIterator>
+ static auto
+ _S_to_string(_InputIterator __first, _InputIterator __last)
+ {
+ using _EcharT
+ = typename std::iterator_traits<_InputIterator>::value_type;
+ static_assert(__detail::__is_encoded_char<_EcharT>);
- static basic_string_view<value_type>
- _S_convert(value_type* __src, __detail::__null_terminated)
- { return __src; }
+#if __cpp_lib_concepts
+ constexpr bool __contiguous = std::contiguous_iterator<_InputIterator>;
+#else
+ constexpr bool __contiguous
+ = is_pointer_v<decltype(std::__niter_base(__first))>;
+#endif
+ if constexpr (__contiguous)
+ {
+ // For contiguous iterators we can just return a string view.
+ const auto* __f = std::__to_address(std::__niter_base(__first));
+ const auto* __l = std::__to_address(std::__niter_base(__last));
+ return basic_string_view<_EcharT>(__f, __l - __f);
+ }
+ else
+ // Conversion requires contiguous characters, so create a string.
+ return basic_string<_EcharT>(__first, __last);
+ }
- static basic_string_view<value_type>
- _S_convert(const value_type* __src, __detail::__null_terminated)
- { return __src; }
+ // path::_S_convert creates a basic_string<value_type> or
+ // basic_string_view<value_type> from a range (either the effective
+ // range of a Source parameter, or a pair of InputIterator parameters),
+ // performing the conversions required by [fs.path.type.cvt].
+ // If the value_type of the range value type is path::value_type,
+ // no encoding conversion is performed. If the range is contiguous
+ // a string_view
- static basic_string_view<value_type>
- _S_convert(value_type* __first, value_type* __last)
- { return {__first, __last - __first}; }
+ static string_type
+ _S_convert(string_type __str)
+ { return __str; }
- static basic_string_view<value_type>
- _S_convert(const value_type* __first, const value_type* __last)
- { return {__first, __last - __first}; }
+ template<typename _Tp>
+ static auto
+ _S_convert(const _Tp& __str)
+ {
+ if constexpr (is_same_v<_Tp, string_type>)
+ return __str;
+ else if constexpr (is_same_v<_Tp, basic_string_view<value_type>>)
+ return __str;
+ else if constexpr (is_same_v<typename _Tp::value_type, value_type>)
+ return basic_string_view<value_type>(__str.data(), __str.size());
+ else
+ return _S_convert(__str.data(), __str.data() + __str.size());
+ }
+
+ template<typename _EcharT>
+ static auto
+ _S_convert(const _EcharT* __first, const _EcharT* __last);
template<typename _Iter>
- static string_type
+ static auto
_S_convert(_Iter __first, _Iter __last)
- {
- using __value_type = typename std::iterator_traits<_Iter>::value_type;
- return _Cvt<typename remove_cv<__value_type>::type>::
- _S_convert(__first, __last);
- }
-
- template<typename _InputIterator>
- static string_type
- _S_convert(_InputIterator __src, __detail::__null_terminated)
- {
- // Read from iterator into basic_string until a null value is seen:
- auto __s = _S_string_from_iter(__src);
- // Convert (if needed) from iterator's value type to path::value_type:
- return string_type(_S_convert(__s.data(), __s.data() + __s.size()));
- }
+ { return _S_convert(_S_to_string(__first, __last)); }
static string_type
_S_convert_loc(const char* __first, const char* __last,
@@ -604,16 +612,14 @@ namespace __detail
static string_type
_S_convert_loc(_Iter __first, _Iter __last, const std::locale& __loc)
{
- const std::string __str(__first, __last);
- return _S_convert_loc(__str.data(), __str.data()+__str.size(), __loc);
+ const auto __s = _S_to_string(__first, __last);
+ return _S_convert_loc(__s.data(), __s.data() + __s.size(), __loc);
}
- template<typename _InputIterator>
+ template<typename _Tp>
static string_type
- _S_convert_loc(_InputIterator __src, __detail::__null_terminated,
- const std::locale& __loc)
+ _S_convert_loc(const _Tp& __s, const std::locale& __loc)
{
- const std::string __s = _S_string_from_iter(__src);
return _S_convert_loc(__s.data(), __s.data() + __s.size(), __loc);
}
@@ -803,100 +809,66 @@ namespace __detail
size_t _M_pos;
};
- // specialize _Cvt for degenerate 'noconv' case
- template<>
- struct path::_Cvt<path::value_type>
+ template<typename _EcharT>
+ auto
+ path::_S_convert(const _EcharT* __f, const _EcharT* __l)
{
- template<typename _Iter>
- static string_type
- _S_convert(_Iter __first, _Iter __last)
- { return string_type{__first, __last}; }
- };
+ static_assert(__detail::__is_encoded_char<_EcharT>);
-#if !defined _GLIBCXX_FILESYSTEM_IS_WINDOWS && defined _GLIBCXX_USE_CHAR8_T
- // For POSIX converting from char8_t to char is also 'noconv'
- template<>
- struct path::_Cvt<char8_t>
- {
- template<typename _Iter>
- static string_type
- _S_convert(_Iter __first, _Iter __last)
- { return string_type(__first, __last); }
- };
+ if constexpr (is_same_v<_EcharT, value_type>)
+ return basic_string_view<value_type>(__f, __l - __f);
+#if !defined _GLIBCXX_FILESYSTEM_IS_WINDOWS && defined _GLIBCXX_USE_CHAR8_T
+ else if constexpr (is_same_v<_EcharT, char8_t>)
+ // For POSIX converting from char8_t to char is also 'noconv'
+ return string_view(reinterpret_cast<const char*>(__f), __l - __f);
#endif
-
- template<typename _CharT>
- struct path::_Cvt
- {
- static string_type
- _S_convert(const _CharT* __f, const _CharT* __l)
- {
-#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
- std::wstring __wstr;
- if constexpr (is_same_v<_CharT, char>)
- {
- struct _UCvt : std::codecvt<wchar_t, char, std::mbstate_t>
- { } __cvt;
- if (__str_codecvt_in_all(__f, __l, __wstr, __cvt))
- return __wstr;
- }
-#ifdef _GLIBCXX_USE_CHAR8_T
- else if constexpr (is_same_v<_CharT, char8_t>)
- {
- const char* __f2 = (const char*)__f;
- const char* __l2 = (const char*)__l;
- std::codecvt_utf8_utf16<wchar_t> __wcvt;
- if (__str_codecvt_in_all(__f2, __l2, __wstr, __wcvt))
- return __wstr;
- }
-#endif
- else // char16_t or char32_t
- {
- struct _UCvt : std::codecvt<_CharT, char, std::mbstate_t>
- { } __cvt;
- std::string __str;
- if (__str_codecvt_out_all(__f, __l, __str, __cvt))
- {
- const char* __f2 = __str.data();
- const char* __l2 = __f2 + __str.size();
- std::codecvt_utf8_utf16<wchar_t> __wcvt;
- if (__str_codecvt_in_all(__f2, __l2, __wstr, __wcvt))
- return __wstr;
- }
- }
-#else // ! windows
- struct _UCvt : std::codecvt<_CharT, char, std::mbstate_t>
- { } __cvt;
- std::string __str;
- if (__str_codecvt_out_all(__f, __l, __str, __cvt))
- return __str;
-#endif
- _GLIBCXX_THROW_OR_ABORT(filesystem_error(
- "Cannot convert character sequence",
- std::make_error_code(errc::illegal_byte_sequence)));
- }
-
- static string_type
- _S_convert(_CharT* __f, _CharT* __l)
- {
- return _S_convert(const_cast<const _CharT*>(__f),
- const_cast<const _CharT*>(__l));
- }
-
- template<typename _Iter>
- static string_type
- _S_convert(_Iter __first, _Iter __last)
+ else
{
- const std::basic_string<_CharT> __str(__first, __last);
- return _S_convert(__str.data(), __str.data() + __str.size());
+#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
+ std::wstring __wstr;
+ if constexpr (is_same_v<_EcharT, char>)
+ {
+ struct _UCvt : std::codecvt<wchar_t, char, std::mbstate_t>
+ { } __cvt;
+ if (__str_codecvt_in_all(__f, __l, __wstr, __cvt))
+ return __wstr;
+ }
+#ifdef _GLIBCXX_USE_CHAR8_T
+ else if constexpr (is_same_v<_EcharT, char8_t>)
+ {
+ const char* __f2 = (const char*)__f;
+ const char* __l2 = (const char*)__l;
+ std::codecvt_utf8_utf16<wchar_t> __wcvt;
+ if (__str_codecvt_in_all(__f2, __l2, __wstr, __wcvt))
+ return __wstr;
+ }
+#endif
+ else // char16_t or char32_t
+ {
+ struct _UCvt : std::codecvt<_EcharT, char, std::mbstate_t>
+ { } __cvt;
+ std::string __str;
+ if (__str_codecvt_out_all(__f, __l, __str, __cvt))
+ {
+ const char* __f2 = __str.data();
+ const char* __l2 = __f2 + __str.size();
+ std::codecvt_utf8_utf16<wchar_t> __wcvt;
+ if (__str_codecvt_in_all(__f2, __l2, __wstr, __wcvt))
+ return __wstr;
+ }
+ }
+#else // ! windows
+ struct _UCvt : std::codecvt<_EcharT, char, std::mbstate_t>
+ { } __cvt;
+ std::string __str;
+ if (__str_codecvt_out_all(__f, __l, __str, __cvt))
+ return __str;
+#endif
+ _GLIBCXX_THROW_OR_ABORT(filesystem_error(
+ "Cannot convert character sequence",
+ std::make_error_code(errc::illegal_byte_sequence)));
}
-
- template<typename _Iter, typename _Cont>
- static string_type
- _S_convert(__gnu_cxx::__normal_iterator<_Iter, _Cont> __first,
- __gnu_cxx::__normal_iterator<_Iter, _Cont> __last)
- { return _S_convert(__first.base(), __last.base()); }
- };
+ }
/// @endcond
@@ -1030,10 +1002,10 @@ namespace __detail
template<typename _CharT>
inline __detail::_Path2<_CharT*>&
- path::operator+=(_CharT __x)
+ path::operator+=(const _CharT __x)
{
- auto* __addr = std::__addressof(__x);
- return concat(__addr, __addr + 1);
+ _M_concat(_S_convert(&__x, &__x + 1));
+ return *this;
}
inline path&
diff --git a/libstdc++-v3/include/experimental/bits/fs_path.h b/libstdc++-v3/include/experimental/bits/fs_path.h
index 69b823a3466..c91937c66d8 100644
--- a/libstdc++-v3/include/experimental/bits/fs_path.h
+++ b/libstdc++-v3/include/experimental/bits/fs_path.h
@@ -495,6 +495,13 @@ namespace __detail
_S_convert_loc(const char* __first, const char* __last,
const std::locale& __loc);
+ static string_type
+ _S_convert_loc(char* __first, char* __last, const std::locale& __loc)
+ {
+ return _S_convert_loc(const_cast<const char*>(__first),
+ const_cast<const char*>(__last), __loc);
+ }
+
template<typename _Iter>
static string_type
_S_convert_loc(_Iter __first, _Iter __last, const std::locale& __loc)
diff --git a/libstdc++-v3/src/c++17/fs_path.cc b/libstdc++-v3/src/c++17/fs_path.cc
index 5ff17741f81..cea7aa08601 100644
--- a/libstdc++-v3/src/c++17/fs_path.cc
+++ b/libstdc++-v3/src/c++17/fs_path.cc
@@ -1949,11 +1949,7 @@ path::_S_convert_loc(const char* __first, const char* __last,
_GLIBCXX_THROW_OR_ABORT(filesystem_error(
"Cannot convert character sequence",
std::make_error_code(errc::illegal_byte_sequence)));
-#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
- return __ws;
-#else
- return _Cvt<wchar_t>::_S_convert(__ws.data(), __ws.data() + __ws.size());
-#endif
+ return _S_convert(std::move(__ws));
#else
return {__first, __last};
#endif
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