From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2181) id E6242384D190; Thu, 7 Jul 2022 23:32:13 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org E6242384D190 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Jonathan Wakely To: gcc-cvs@gcc.gnu.org, libstdc++-cvs@gcc.gnu.org Subject: [gcc r11-10118] libstdc++: std::basic_regex should treat '\0' as an ordinary char [PR84110] X-Act-Checkin: gcc X-Git-Author: Jonathan Wakely X-Git-Refname: refs/heads/releases/gcc-11 X-Git-Oldrev: 80056e27a6e8b3d00a74343bde931d583561ffe9 X-Git-Newrev: 5df21c00aedb7878b8854901e95d7eda70266d31 Message-Id: <20220707233213.E6242384D190@sourceware.org> Date: Thu, 7 Jul 2022 23:32:13 +0000 (GMT) X-BeenThere: libstdc++-cvs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libstdc++-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 07 Jul 2022 23:32:14 -0000 https://gcc.gnu.org/g:5df21c00aedb7878b8854901e95d7eda70266d31 commit r11-10118-g5df21c00aedb7878b8854901e95d7eda70266d31 Author: Jonathan Wakely Date: Wed Sep 29 13:48:11 2021 +0100 libstdc++: std::basic_regex should treat '\0' as an ordinary char [PR84110] When the input sequence contains a _CharT(0) character, the strchr call in _Scanner<_CharT>::_M_scan_normal() will search for '\0' and so return a pointer to the terminating null at the end of the string. This makes the scanner think it's found a special character. Because it doesn't match any of the actual special characters, we fall off the end of the function (or assert in debug mode). We should check for a null character explicitly and either treat it as an ordinary character (for the ECMAScript grammar) or an error (for all others). I'm not 100% sure that's right, but it seems consistent with the POSIX RE rules where a '\0' means the end of the regex pattern or the end of the sequence being matched. Signed-off-by: Jonathan Wakely libstdc++-v3/ChangeLog: PR libstdc++/84110 * include/bits/regex_error.h (regex_constants::_S_null): New error code for internal use. * include/bits/regex_scanner.tcc (_Scanner::_M_scan_normal()): Check for null character. * testsuite/28_regex/basic_regex/84110.cc: New test. (cherry picked from commit b701e1f8f6870c0f8cb4050674da489101dd05a5) Diff: --- libstdc++-v3/include/bits/regex_error.h | 1 + libstdc++-v3/include/bits/regex_scanner.tcc | 10 ++++++ .../testsuite/28_regex/basic_regex/84110.cc | 39 ++++++++++++++++++++++ 3 files changed, 50 insertions(+) diff --git a/libstdc++-v3/include/bits/regex_error.h b/libstdc++-v3/include/bits/regex_error.h index 27593833544..9212fd31552 100644 --- a/libstdc++-v3/include/bits/regex_error.h +++ b/libstdc++-v3/include/bits/regex_error.h @@ -61,6 +61,7 @@ namespace regex_constants _S_error_badrepeat, _S_error_complexity, _S_error_stack, + _S_null }; /** The expression contained an invalid collating element name. */ diff --git a/libstdc++-v3/include/bits/regex_scanner.tcc b/libstdc++-v3/include/bits/regex_scanner.tcc index a3512083f0e..04f78f0baee 100644 --- a/libstdc++-v3/include/bits/regex_scanner.tcc +++ b/libstdc++-v3/include/bits/regex_scanner.tcc @@ -176,6 +176,16 @@ namespace __detail _M_state = _S_state_in_brace; _M_token = _S_token_interval_begin; } + else if (__builtin_expect(__c == _CharT(0), false)) + { + if (!_M_is_ecma()) + { + __throw_regex_error(regex_constants::_S_null, + "Unexpected null character in regular expression"); + } + _M_token = _S_token_ord_char; + _M_value.assign(1, __c); + } else if (__c != ']' && __c != '}') { auto __it = _M_token_tbl; diff --git a/libstdc++-v3/testsuite/28_regex/basic_regex/84110.cc b/libstdc++-v3/testsuite/28_regex/basic_regex/84110.cc new file mode 100644 index 00000000000..b9971dcaac5 --- /dev/null +++ b/libstdc++-v3/testsuite/28_regex/basic_regex/84110.cc @@ -0,0 +1,39 @@ +// { dg-do run { target c++11 } } +#include +#include +#include + +void test01() +{ + const std::string s(1ul, '\0'); + std::regex re(s); + VERIFY( std::regex_match(s, re) ); // PR libstdc++/84110 + +#if __cpp_exceptions + using namespace std::regex_constants; + for (auto syn : {basic, extended, awk, grep, egrep}) + { + try + { + std::regex{s, syn}; // '\0' is not valid for other grammars + VERIFY( false ); + } + catch (const std::regex_error&) + { + } + } +#endif +} + +void test02() +{ + const std::string s("uh-\0h", 5); + std::regex re(s); + VERIFY( std::regex_match(s, re) ); +} + +int main() +{ + test01(); + test02(); +}