git/grep.h

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#ifndef GREP_H
#define GREP_H
#include "color.h"
grep: add support for PCRE v2 Add support for v2 of the PCRE API. This is a new major version of PCRE that came out in early 2015[1]. The regular expression syntax is the same, but while the API is similar, pretty much every function is either renamed or takes different arguments. Thus using it via entirely new functions makes sense, as opposed to trying to e.g. have one compile_pcre_pattern() that would call either PCRE v1 or v2 functions. Git can now be compiled with either USE_LIBPCRE1=YesPlease or USE_LIBPCRE2=YesPlease, with USE_LIBPCRE=YesPlease currently being a synonym for the former. Providing both is a compile-time error. With earlier patches to enable JIT for PCRE v1 the performance of the release versions of both libraries is almost exactly the same, with PCRE v2 being around 1% slower. However after I reported this to the pcre-dev mailing list[2] I got a lot of help with the API use from Zoltán Herczeg, he subsequently optimized some of the JIT functionality in v2 of the library. Running the p7820-grep-engines.sh performance test against the latest Subversion trunk of both, with both them and git compiled as -O3, and the test run against linux.git, gives the following results. Just the /perl/ tests shown: $ GIT_PERF_REPEAT_COUNT=30 GIT_PERF_LARGE_REPO=~/g/linux GIT_PERF_MAKE_COMMAND='grep -q LIBPCRE2 Makefile && make -j8 USE_LIBPCRE2=YesPlease CC=~/perl5/installed/bin/gcc NO_R_TO_GCC_LINKER=YesPlease CFLAGS=-O3 LIBPCREDIR=/home/avar/g/pcre2/inst LDFLAGS=-Wl,-rpath,/home/avar/g/pcre2/inst/lib || make -j8 USE_LIBPCRE=YesPlease CC=~/perl5/installed/bin/gcc NO_R_TO_GCC_LINKER=YesPlease CFLAGS=-O3 LIBPCREDIR=/home/avar/g/pcre/inst LDFLAGS=-Wl,-rpath,/home/avar/g/pcre/inst/lib' ./run HEAD~5 HEAD~ HEAD p7820-grep-engines.sh [...] Test HEAD~5 HEAD~ HEAD ----------------------------------------------------------------------------------------------------------------- 7820.3: perl grep 'how.to' 0.31(1.10+0.48) 0.21(0.35+0.56) -32.3% 0.21(0.34+0.55) -32.3% 7820.7: perl grep '^how to' 0.56(2.70+0.40) 0.24(0.64+0.52) -57.1% 0.20(0.28+0.60) -64.3% 7820.11: perl grep '[how] to' 0.56(2.66+0.38) 0.29(0.95+0.45) -48.2% 0.23(0.45+0.54) -58.9% 7820.15: perl grep '(e.t[^ ]*|v.ry) rare' 1.02(5.77+0.42) 0.31(1.02+0.54) -69.6% 0.23(0.50+0.54) -77.5% 7820.19: perl grep 'm(ú|u)lt.b(æ|y)te' 0.38(1.57+0.42) 0.27(0.85+0.46) -28.9% 0.21(0.33+0.57) -44.7% See commit ("perf: add a comparison test of grep regex engines", 2017-04-19) for details on the machine the above test run was executed on. Here HEAD~2 is git with PCRE v1 without JIT, HEAD~ is PCRE v1 with JIT, and HEAD is PCRE v2 (also with JIT). See previous commits of mine mentioning p7820-grep-engines.sh for more details on the test setup. For ease of readability, a different run just of HEAD~ (PCRE v1 with JIT v.s. PCRE v2), again with just the /perl/ tests shown: [...] Test HEAD~ HEAD ---------------------------------------------------------------------------------------- 7820.3: perl grep 'how.to' 0.21(0.42+0.52) 0.21(0.31+0.58) +0.0% 7820.7: perl grep '^how to' 0.25(0.65+0.50) 0.20(0.31+0.57) -20.0% 7820.11: perl grep '[how] to' 0.30(0.90+0.50) 0.23(0.46+0.53) -23.3% 7820.15: perl grep '(e.t[^ ]*|v.ry) rare' 0.30(1.19+0.38) 0.23(0.51+0.51) -23.3% 7820.19: perl grep 'm(ú|u)lt.b(æ|y)te' 0.27(0.84+0.48) 0.21(0.34+0.57) -22.2% I.e. the two are either neck-to-neck, but PCRE v2 usually pulls ahead, when it does it's around 20% faster. A brief note on thread safety: As noted in pcre2api(3) & pcre2jit(3) the compiled pattern can be shared between threads, but not some of the JIT context, however the grep threading support does all pattern & JIT compilation in separate threads, so this code doesn't need to concern itself with thread safety. See commit 63e7e9d8b6 ("git-grep: Learn PCRE", 2011-05-09) for the initial addition of PCRE v1. This change follows some of the same patterns it did (and which were discussed on list at the time), e.g. mocking up types with typedef instead of ifdef-ing them out when USE_LIBPCRE2 isn't defined. This adds some trivial memory use to the program, but makes the code look nicer. 1. https://lists.exim.org/lurker/message/20150105.162835.0666407a.en.html 2. https://lists.exim.org/lurker/thread/20170419.172322.833ee099.en.html Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-01 18:20:56 +00:00
#ifdef USE_LIBPCRE2
#define PCRE2_CODE_UNIT_WIDTH 8
#include <pcre2.h>
#if (PCRE2_MAJOR >= 10 && PCRE2_MINOR >= 36) || PCRE2_MAJOR >= 11
#define GIT_PCRE2_VERSION_10_36_OR_HIGHER
#endif
#if (PCRE2_MAJOR >= 10 && PCRE2_MINOR >= 35) || PCRE2_MAJOR >= 11
#define GIT_PCRE2_VERSION_10_35_OR_HIGHER
#endif
#if (PCRE2_MAJOR >= 10 && PCRE2_MINOR >= 34) || PCRE2_MAJOR >= 11
#define GIT_PCRE2_VERSION_10_34_OR_HIGHER
#endif
grep: add support for PCRE v2 Add support for v2 of the PCRE API. This is a new major version of PCRE that came out in early 2015[1]. The regular expression syntax is the same, but while the API is similar, pretty much every function is either renamed or takes different arguments. Thus using it via entirely new functions makes sense, as opposed to trying to e.g. have one compile_pcre_pattern() that would call either PCRE v1 or v2 functions. Git can now be compiled with either USE_LIBPCRE1=YesPlease or USE_LIBPCRE2=YesPlease, with USE_LIBPCRE=YesPlease currently being a synonym for the former. Providing both is a compile-time error. With earlier patches to enable JIT for PCRE v1 the performance of the release versions of both libraries is almost exactly the same, with PCRE v2 being around 1% slower. However after I reported this to the pcre-dev mailing list[2] I got a lot of help with the API use from Zoltán Herczeg, he subsequently optimized some of the JIT functionality in v2 of the library. Running the p7820-grep-engines.sh performance test against the latest Subversion trunk of both, with both them and git compiled as -O3, and the test run against linux.git, gives the following results. Just the /perl/ tests shown: $ GIT_PERF_REPEAT_COUNT=30 GIT_PERF_LARGE_REPO=~/g/linux GIT_PERF_MAKE_COMMAND='grep -q LIBPCRE2 Makefile && make -j8 USE_LIBPCRE2=YesPlease CC=~/perl5/installed/bin/gcc NO_R_TO_GCC_LINKER=YesPlease CFLAGS=-O3 LIBPCREDIR=/home/avar/g/pcre2/inst LDFLAGS=-Wl,-rpath,/home/avar/g/pcre2/inst/lib || make -j8 USE_LIBPCRE=YesPlease CC=~/perl5/installed/bin/gcc NO_R_TO_GCC_LINKER=YesPlease CFLAGS=-O3 LIBPCREDIR=/home/avar/g/pcre/inst LDFLAGS=-Wl,-rpath,/home/avar/g/pcre/inst/lib' ./run HEAD~5 HEAD~ HEAD p7820-grep-engines.sh [...] Test HEAD~5 HEAD~ HEAD ----------------------------------------------------------------------------------------------------------------- 7820.3: perl grep 'how.to' 0.31(1.10+0.48) 0.21(0.35+0.56) -32.3% 0.21(0.34+0.55) -32.3% 7820.7: perl grep '^how to' 0.56(2.70+0.40) 0.24(0.64+0.52) -57.1% 0.20(0.28+0.60) -64.3% 7820.11: perl grep '[how] to' 0.56(2.66+0.38) 0.29(0.95+0.45) -48.2% 0.23(0.45+0.54) -58.9% 7820.15: perl grep '(e.t[^ ]*|v.ry) rare' 1.02(5.77+0.42) 0.31(1.02+0.54) -69.6% 0.23(0.50+0.54) -77.5% 7820.19: perl grep 'm(ú|u)lt.b(æ|y)te' 0.38(1.57+0.42) 0.27(0.85+0.46) -28.9% 0.21(0.33+0.57) -44.7% See commit ("perf: add a comparison test of grep regex engines", 2017-04-19) for details on the machine the above test run was executed on. Here HEAD~2 is git with PCRE v1 without JIT, HEAD~ is PCRE v1 with JIT, and HEAD is PCRE v2 (also with JIT). See previous commits of mine mentioning p7820-grep-engines.sh for more details on the test setup. For ease of readability, a different run just of HEAD~ (PCRE v1 with JIT v.s. PCRE v2), again with just the /perl/ tests shown: [...] Test HEAD~ HEAD ---------------------------------------------------------------------------------------- 7820.3: perl grep 'how.to' 0.21(0.42+0.52) 0.21(0.31+0.58) +0.0% 7820.7: perl grep '^how to' 0.25(0.65+0.50) 0.20(0.31+0.57) -20.0% 7820.11: perl grep '[how] to' 0.30(0.90+0.50) 0.23(0.46+0.53) -23.3% 7820.15: perl grep '(e.t[^ ]*|v.ry) rare' 0.30(1.19+0.38) 0.23(0.51+0.51) -23.3% 7820.19: perl grep 'm(ú|u)lt.b(æ|y)te' 0.27(0.84+0.48) 0.21(0.34+0.57) -22.2% I.e. the two are either neck-to-neck, but PCRE v2 usually pulls ahead, when it does it's around 20% faster. A brief note on thread safety: As noted in pcre2api(3) & pcre2jit(3) the compiled pattern can be shared between threads, but not some of the JIT context, however the grep threading support does all pattern & JIT compilation in separate threads, so this code doesn't need to concern itself with thread safety. See commit 63e7e9d8b6 ("git-grep: Learn PCRE", 2011-05-09) for the initial addition of PCRE v1. This change follows some of the same patterns it did (and which were discussed on list at the time), e.g. mocking up types with typedef instead of ifdef-ing them out when USE_LIBPCRE2 isn't defined. This adds some trivial memory use to the program, but makes the code look nicer. 1. https://lists.exim.org/lurker/message/20150105.162835.0666407a.en.html 2. https://lists.exim.org/lurker/thread/20170419.172322.833ee099.en.html Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-01 18:20:56 +00:00
#else
typedef int pcre2_code;
typedef int pcre2_match_data;
typedef int pcre2_compile_context;
grep/pcre2: move back to thread-only PCREv2 structures Change the setup of the "pcre2_general_context" to happen per-thread in compile_pcre2_pattern() instead of in grep_init(). This change brings it in line with how the rest of the pcre2_* members in the grep_pat structure are set up. As noted in the preceding commit the approach 513f2b0bbd4 (grep: make PCRE2 aware of custom allocator, 2019-10-16) took to allocate the pcre2_general_context seems to have been initially based on a misunderstanding of how PCREv2 memory allocation works. The approach of creating a global context in grep_init() is just added complexity for almost zero gain. On my system it's 24 bytes saved per-thread. For comparison PCREv2 will then go on to allocate at least a kilobyte for its own thread-local state. As noted in 6d423dd542f (grep: don't redundantly compile throwaway patterns under threading, 2017-05-25) the grep code is intentionally not trying to micro-optimize allocations by e.g. sharing some PCREv2 structures globally, while making others thread-local. So let's remove this special case and make all of them thread-local again for simplicity. With this change we could move the pcre2_{malloc,free} functions around to live closer to their current use. I'm not doing that here to keep this change small, that cleanup will be done in a follow-up commit. See also the discussion in 94da9193a6 (grep: add support for PCRE v2, 2017-06-01) about thread safety, and Johannes's comments[1] to the effect that we should be doing what this patch is doing. 1. https://lore.kernel.org/git/nycvar.QRO.7.76.6.1908052120302.46@tvgsbejvaqbjf.bet/ Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-02-18 00:07:27 +00:00
typedef int pcre2_general_context;
grep: add support for PCRE v2 Add support for v2 of the PCRE API. This is a new major version of PCRE that came out in early 2015[1]. The regular expression syntax is the same, but while the API is similar, pretty much every function is either renamed or takes different arguments. Thus using it via entirely new functions makes sense, as opposed to trying to e.g. have one compile_pcre_pattern() that would call either PCRE v1 or v2 functions. Git can now be compiled with either USE_LIBPCRE1=YesPlease or USE_LIBPCRE2=YesPlease, with USE_LIBPCRE=YesPlease currently being a synonym for the former. Providing both is a compile-time error. With earlier patches to enable JIT for PCRE v1 the performance of the release versions of both libraries is almost exactly the same, with PCRE v2 being around 1% slower. However after I reported this to the pcre-dev mailing list[2] I got a lot of help with the API use from Zoltán Herczeg, he subsequently optimized some of the JIT functionality in v2 of the library. Running the p7820-grep-engines.sh performance test against the latest Subversion trunk of both, with both them and git compiled as -O3, and the test run against linux.git, gives the following results. Just the /perl/ tests shown: $ GIT_PERF_REPEAT_COUNT=30 GIT_PERF_LARGE_REPO=~/g/linux GIT_PERF_MAKE_COMMAND='grep -q LIBPCRE2 Makefile && make -j8 USE_LIBPCRE2=YesPlease CC=~/perl5/installed/bin/gcc NO_R_TO_GCC_LINKER=YesPlease CFLAGS=-O3 LIBPCREDIR=/home/avar/g/pcre2/inst LDFLAGS=-Wl,-rpath,/home/avar/g/pcre2/inst/lib || make -j8 USE_LIBPCRE=YesPlease CC=~/perl5/installed/bin/gcc NO_R_TO_GCC_LINKER=YesPlease CFLAGS=-O3 LIBPCREDIR=/home/avar/g/pcre/inst LDFLAGS=-Wl,-rpath,/home/avar/g/pcre/inst/lib' ./run HEAD~5 HEAD~ HEAD p7820-grep-engines.sh [...] Test HEAD~5 HEAD~ HEAD ----------------------------------------------------------------------------------------------------------------- 7820.3: perl grep 'how.to' 0.31(1.10+0.48) 0.21(0.35+0.56) -32.3% 0.21(0.34+0.55) -32.3% 7820.7: perl grep '^how to' 0.56(2.70+0.40) 0.24(0.64+0.52) -57.1% 0.20(0.28+0.60) -64.3% 7820.11: perl grep '[how] to' 0.56(2.66+0.38) 0.29(0.95+0.45) -48.2% 0.23(0.45+0.54) -58.9% 7820.15: perl grep '(e.t[^ ]*|v.ry) rare' 1.02(5.77+0.42) 0.31(1.02+0.54) -69.6% 0.23(0.50+0.54) -77.5% 7820.19: perl grep 'm(ú|u)lt.b(æ|y)te' 0.38(1.57+0.42) 0.27(0.85+0.46) -28.9% 0.21(0.33+0.57) -44.7% See commit ("perf: add a comparison test of grep regex engines", 2017-04-19) for details on the machine the above test run was executed on. Here HEAD~2 is git with PCRE v1 without JIT, HEAD~ is PCRE v1 with JIT, and HEAD is PCRE v2 (also with JIT). See previous commits of mine mentioning p7820-grep-engines.sh for more details on the test setup. For ease of readability, a different run just of HEAD~ (PCRE v1 with JIT v.s. PCRE v2), again with just the /perl/ tests shown: [...] Test HEAD~ HEAD ---------------------------------------------------------------------------------------- 7820.3: perl grep 'how.to' 0.21(0.42+0.52) 0.21(0.31+0.58) +0.0% 7820.7: perl grep '^how to' 0.25(0.65+0.50) 0.20(0.31+0.57) -20.0% 7820.11: perl grep '[how] to' 0.30(0.90+0.50) 0.23(0.46+0.53) -23.3% 7820.15: perl grep '(e.t[^ ]*|v.ry) rare' 0.30(1.19+0.38) 0.23(0.51+0.51) -23.3% 7820.19: perl grep 'm(ú|u)lt.b(æ|y)te' 0.27(0.84+0.48) 0.21(0.34+0.57) -22.2% I.e. the two are either neck-to-neck, but PCRE v2 usually pulls ahead, when it does it's around 20% faster. A brief note on thread safety: As noted in pcre2api(3) & pcre2jit(3) the compiled pattern can be shared between threads, but not some of the JIT context, however the grep threading support does all pattern & JIT compilation in separate threads, so this code doesn't need to concern itself with thread safety. See commit 63e7e9d8b6 ("git-grep: Learn PCRE", 2011-05-09) for the initial addition of PCRE v1. This change follows some of the same patterns it did (and which were discussed on list at the time), e.g. mocking up types with typedef instead of ifdef-ing them out when USE_LIBPCRE2 isn't defined. This adds some trivial memory use to the program, but makes the code look nicer. 1. https://lists.exim.org/lurker/message/20150105.162835.0666407a.en.html 2. https://lists.exim.org/lurker/thread/20170419.172322.833ee099.en.html Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-01 18:20:56 +00:00
#endif
#ifndef PCRE2_MATCH_INVALID_UTF
/* PCRE2_MATCH_* dummy also with !USE_LIBPCRE2, for test-pcre2-config.c */
#define PCRE2_MATCH_INVALID_UTF 0
#endif
#include "thread-utils.h"
#include "userdiff.h"
struct repository;
enum grep_pat_token {
GREP_PATTERN,
GREP_PATTERN_HEAD,
GREP_PATTERN_BODY,
GREP_AND,
GREP_OPEN_PAREN,
GREP_CLOSE_PAREN,
GREP_NOT,
GREP_OR
};
enum grep_context {
GREP_CONTEXT_HEAD,
GREP_CONTEXT_BODY
};
log --author/--committer: really match only with name part When we tried to find commits done by AUTHOR, the first implementation tried to pattern match a line with "^author .*AUTHOR", which later was enhanced to strip leading caret and look for "^author AUTHOR" when the search pattern was anchored at the left end (i.e. --author="^AUTHOR"). This had a few problems: * When looking for fixed strings (e.g. "git log -F --author=x --grep=y"), the regexp internally used "^author .*x" would never match anything; * To match at the end (e.g. "git log --author='google.com>$'"), the generated regexp has to also match the trailing timestamp part the commit header lines have. Also, in order to determine if the '$' at the end means "match at the end of the line" or just a literal dollar sign (probably backslash-quoted), we would need to parse the regexp ourselves. An earlier alternative tried to make sure that a line matches "^author " (to limit by field name) and the user supplied pattern at the same time. While it solved the -F problem by introducing a special override for matching the "^author ", it did not solve the trailing timestamp nor tail match problem. It also would have matched every commit if --author=author was asked for, not because the author's email part had this string, but because every commit header line that talks about the author begins with that field name, regardleses of who wrote it. Instead of piling more hacks on top of hacks, this rethinks the grep machinery that is used to look for strings in the commit header, and makes sure that (1) field name matches literally at the beginning of the line, followed by a SP, and (2) the user supplied pattern is matched against the remainder of the line, excluding the trailing timestamp data. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-09-05 05:15:02 +00:00
enum grep_header_field {
GREP_HEADER_FIELD_MIN = 0,
GREP_HEADER_AUTHOR = GREP_HEADER_FIELD_MIN,
GREP_HEADER_COMMITTER,
GREP_HEADER_REFLOG,
/* Must be at the end of the enum */
GREP_HEADER_FIELD_MAX
log --author/--committer: really match only with name part When we tried to find commits done by AUTHOR, the first implementation tried to pattern match a line with "^author .*AUTHOR", which later was enhanced to strip leading caret and look for "^author AUTHOR" when the search pattern was anchored at the left end (i.e. --author="^AUTHOR"). This had a few problems: * When looking for fixed strings (e.g. "git log -F --author=x --grep=y"), the regexp internally used "^author .*x" would never match anything; * To match at the end (e.g. "git log --author='google.com>$'"), the generated regexp has to also match the trailing timestamp part the commit header lines have. Also, in order to determine if the '$' at the end means "match at the end of the line" or just a literal dollar sign (probably backslash-quoted), we would need to parse the regexp ourselves. An earlier alternative tried to make sure that a line matches "^author " (to limit by field name) and the user supplied pattern at the same time. While it solved the -F problem by introducing a special override for matching the "^author ", it did not solve the trailing timestamp nor tail match problem. It also would have matched every commit if --author=author was asked for, not because the author's email part had this string, but because every commit header line that talks about the author begins with that field name, regardleses of who wrote it. Instead of piling more hacks on top of hacks, this rethinks the grep machinery that is used to look for strings in the commit header, and makes sure that (1) field name matches literally at the beginning of the line, followed by a SP, and (2) the user supplied pattern is matched against the remainder of the line, excluding the trailing timestamp data. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-09-05 05:15:02 +00:00
};
enum grep_color {
GREP_COLOR_CONTEXT,
GREP_COLOR_FILENAME,
GREP_COLOR_FUNCTION,
GREP_COLOR_LINENO,
GREP_COLOR_COLUMNNO,
GREP_COLOR_MATCH_CONTEXT,
GREP_COLOR_MATCH_SELECTED,
GREP_COLOR_SELECTED,
GREP_COLOR_SEP,
NR_GREP_COLORS
};
struct grep_pat {
struct grep_pat *next;
const char *origin;
int no;
enum grep_pat_token token;
char *pattern;
size_t patternlen;
log --author/--committer: really match only with name part When we tried to find commits done by AUTHOR, the first implementation tried to pattern match a line with "^author .*AUTHOR", which later was enhanced to strip leading caret and look for "^author AUTHOR" when the search pattern was anchored at the left end (i.e. --author="^AUTHOR"). This had a few problems: * When looking for fixed strings (e.g. "git log -F --author=x --grep=y"), the regexp internally used "^author .*x" would never match anything; * To match at the end (e.g. "git log --author='google.com>$'"), the generated regexp has to also match the trailing timestamp part the commit header lines have. Also, in order to determine if the '$' at the end means "match at the end of the line" or just a literal dollar sign (probably backslash-quoted), we would need to parse the regexp ourselves. An earlier alternative tried to make sure that a line matches "^author " (to limit by field name) and the user supplied pattern at the same time. While it solved the -F problem by introducing a special override for matching the "^author ", it did not solve the trailing timestamp nor tail match problem. It also would have matched every commit if --author=author was asked for, not because the author's email part had this string, but because every commit header line that talks about the author begins with that field name, regardleses of who wrote it. Instead of piling more hacks on top of hacks, this rethinks the grep machinery that is used to look for strings in the commit header, and makes sure that (1) field name matches literally at the beginning of the line, followed by a SP, and (2) the user supplied pattern is matched against the remainder of the line, excluding the trailing timestamp data. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-09-05 05:15:02 +00:00
enum grep_header_field field;
regex_t regexp;
grep: add support for PCRE v2 Add support for v2 of the PCRE API. This is a new major version of PCRE that came out in early 2015[1]. The regular expression syntax is the same, but while the API is similar, pretty much every function is either renamed or takes different arguments. Thus using it via entirely new functions makes sense, as opposed to trying to e.g. have one compile_pcre_pattern() that would call either PCRE v1 or v2 functions. Git can now be compiled with either USE_LIBPCRE1=YesPlease or USE_LIBPCRE2=YesPlease, with USE_LIBPCRE=YesPlease currently being a synonym for the former. Providing both is a compile-time error. With earlier patches to enable JIT for PCRE v1 the performance of the release versions of both libraries is almost exactly the same, with PCRE v2 being around 1% slower. However after I reported this to the pcre-dev mailing list[2] I got a lot of help with the API use from Zoltán Herczeg, he subsequently optimized some of the JIT functionality in v2 of the library. Running the p7820-grep-engines.sh performance test against the latest Subversion trunk of both, with both them and git compiled as -O3, and the test run against linux.git, gives the following results. Just the /perl/ tests shown: $ GIT_PERF_REPEAT_COUNT=30 GIT_PERF_LARGE_REPO=~/g/linux GIT_PERF_MAKE_COMMAND='grep -q LIBPCRE2 Makefile && make -j8 USE_LIBPCRE2=YesPlease CC=~/perl5/installed/bin/gcc NO_R_TO_GCC_LINKER=YesPlease CFLAGS=-O3 LIBPCREDIR=/home/avar/g/pcre2/inst LDFLAGS=-Wl,-rpath,/home/avar/g/pcre2/inst/lib || make -j8 USE_LIBPCRE=YesPlease CC=~/perl5/installed/bin/gcc NO_R_TO_GCC_LINKER=YesPlease CFLAGS=-O3 LIBPCREDIR=/home/avar/g/pcre/inst LDFLAGS=-Wl,-rpath,/home/avar/g/pcre/inst/lib' ./run HEAD~5 HEAD~ HEAD p7820-grep-engines.sh [...] Test HEAD~5 HEAD~ HEAD ----------------------------------------------------------------------------------------------------------------- 7820.3: perl grep 'how.to' 0.31(1.10+0.48) 0.21(0.35+0.56) -32.3% 0.21(0.34+0.55) -32.3% 7820.7: perl grep '^how to' 0.56(2.70+0.40) 0.24(0.64+0.52) -57.1% 0.20(0.28+0.60) -64.3% 7820.11: perl grep '[how] to' 0.56(2.66+0.38) 0.29(0.95+0.45) -48.2% 0.23(0.45+0.54) -58.9% 7820.15: perl grep '(e.t[^ ]*|v.ry) rare' 1.02(5.77+0.42) 0.31(1.02+0.54) -69.6% 0.23(0.50+0.54) -77.5% 7820.19: perl grep 'm(ú|u)lt.b(æ|y)te' 0.38(1.57+0.42) 0.27(0.85+0.46) -28.9% 0.21(0.33+0.57) -44.7% See commit ("perf: add a comparison test of grep regex engines", 2017-04-19) for details on the machine the above test run was executed on. Here HEAD~2 is git with PCRE v1 without JIT, HEAD~ is PCRE v1 with JIT, and HEAD is PCRE v2 (also with JIT). See previous commits of mine mentioning p7820-grep-engines.sh for more details on the test setup. For ease of readability, a different run just of HEAD~ (PCRE v1 with JIT v.s. PCRE v2), again with just the /perl/ tests shown: [...] Test HEAD~ HEAD ---------------------------------------------------------------------------------------- 7820.3: perl grep 'how.to' 0.21(0.42+0.52) 0.21(0.31+0.58) +0.0% 7820.7: perl grep '^how to' 0.25(0.65+0.50) 0.20(0.31+0.57) -20.0% 7820.11: perl grep '[how] to' 0.30(0.90+0.50) 0.23(0.46+0.53) -23.3% 7820.15: perl grep '(e.t[^ ]*|v.ry) rare' 0.30(1.19+0.38) 0.23(0.51+0.51) -23.3% 7820.19: perl grep 'm(ú|u)lt.b(æ|y)te' 0.27(0.84+0.48) 0.21(0.34+0.57) -22.2% I.e. the two are either neck-to-neck, but PCRE v2 usually pulls ahead, when it does it's around 20% faster. A brief note on thread safety: As noted in pcre2api(3) & pcre2jit(3) the compiled pattern can be shared between threads, but not some of the JIT context, however the grep threading support does all pattern & JIT compilation in separate threads, so this code doesn't need to concern itself with thread safety. See commit 63e7e9d8b6 ("git-grep: Learn PCRE", 2011-05-09) for the initial addition of PCRE v1. This change follows some of the same patterns it did (and which were discussed on list at the time), e.g. mocking up types with typedef instead of ifdef-ing them out when USE_LIBPCRE2 isn't defined. This adds some trivial memory use to the program, but makes the code look nicer. 1. https://lists.exim.org/lurker/message/20150105.162835.0666407a.en.html 2. https://lists.exim.org/lurker/thread/20170419.172322.833ee099.en.html Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-01 18:20:56 +00:00
pcre2_code *pcre2_pattern;
pcre2_match_data *pcre2_match_data;
pcre2_compile_context *pcre2_compile_context;
grep/pcre2: move back to thread-only PCREv2 structures Change the setup of the "pcre2_general_context" to happen per-thread in compile_pcre2_pattern() instead of in grep_init(). This change brings it in line with how the rest of the pcre2_* members in the grep_pat structure are set up. As noted in the preceding commit the approach 513f2b0bbd4 (grep: make PCRE2 aware of custom allocator, 2019-10-16) took to allocate the pcre2_general_context seems to have been initially based on a misunderstanding of how PCREv2 memory allocation works. The approach of creating a global context in grep_init() is just added complexity for almost zero gain. On my system it's 24 bytes saved per-thread. For comparison PCREv2 will then go on to allocate at least a kilobyte for its own thread-local state. As noted in 6d423dd542f (grep: don't redundantly compile throwaway patterns under threading, 2017-05-25) the grep code is intentionally not trying to micro-optimize allocations by e.g. sharing some PCREv2 structures globally, while making others thread-local. So let's remove this special case and make all of them thread-local again for simplicity. With this change we could move the pcre2_{malloc,free} functions around to live closer to their current use. I'm not doing that here to keep this change small, that cleanup will be done in a follow-up commit. See also the discussion in 94da9193a6 (grep: add support for PCRE v2, 2017-06-01) about thread safety, and Johannes's comments[1] to the effect that we should be doing what this patch is doing. 1. https://lore.kernel.org/git/nycvar.QRO.7.76.6.1908052120302.46@tvgsbejvaqbjf.bet/ Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-02-18 00:07:27 +00:00
pcre2_general_context *pcre2_general_context;
const uint8_t *pcre2_tables;
grep: add support for PCRE v2 Add support for v2 of the PCRE API. This is a new major version of PCRE that came out in early 2015[1]. The regular expression syntax is the same, but while the API is similar, pretty much every function is either renamed or takes different arguments. Thus using it via entirely new functions makes sense, as opposed to trying to e.g. have one compile_pcre_pattern() that would call either PCRE v1 or v2 functions. Git can now be compiled with either USE_LIBPCRE1=YesPlease or USE_LIBPCRE2=YesPlease, with USE_LIBPCRE=YesPlease currently being a synonym for the former. Providing both is a compile-time error. With earlier patches to enable JIT for PCRE v1 the performance of the release versions of both libraries is almost exactly the same, with PCRE v2 being around 1% slower. However after I reported this to the pcre-dev mailing list[2] I got a lot of help with the API use from Zoltán Herczeg, he subsequently optimized some of the JIT functionality in v2 of the library. Running the p7820-grep-engines.sh performance test against the latest Subversion trunk of both, with both them and git compiled as -O3, and the test run against linux.git, gives the following results. Just the /perl/ tests shown: $ GIT_PERF_REPEAT_COUNT=30 GIT_PERF_LARGE_REPO=~/g/linux GIT_PERF_MAKE_COMMAND='grep -q LIBPCRE2 Makefile && make -j8 USE_LIBPCRE2=YesPlease CC=~/perl5/installed/bin/gcc NO_R_TO_GCC_LINKER=YesPlease CFLAGS=-O3 LIBPCREDIR=/home/avar/g/pcre2/inst LDFLAGS=-Wl,-rpath,/home/avar/g/pcre2/inst/lib || make -j8 USE_LIBPCRE=YesPlease CC=~/perl5/installed/bin/gcc NO_R_TO_GCC_LINKER=YesPlease CFLAGS=-O3 LIBPCREDIR=/home/avar/g/pcre/inst LDFLAGS=-Wl,-rpath,/home/avar/g/pcre/inst/lib' ./run HEAD~5 HEAD~ HEAD p7820-grep-engines.sh [...] Test HEAD~5 HEAD~ HEAD ----------------------------------------------------------------------------------------------------------------- 7820.3: perl grep 'how.to' 0.31(1.10+0.48) 0.21(0.35+0.56) -32.3% 0.21(0.34+0.55) -32.3% 7820.7: perl grep '^how to' 0.56(2.70+0.40) 0.24(0.64+0.52) -57.1% 0.20(0.28+0.60) -64.3% 7820.11: perl grep '[how] to' 0.56(2.66+0.38) 0.29(0.95+0.45) -48.2% 0.23(0.45+0.54) -58.9% 7820.15: perl grep '(e.t[^ ]*|v.ry) rare' 1.02(5.77+0.42) 0.31(1.02+0.54) -69.6% 0.23(0.50+0.54) -77.5% 7820.19: perl grep 'm(ú|u)lt.b(æ|y)te' 0.38(1.57+0.42) 0.27(0.85+0.46) -28.9% 0.21(0.33+0.57) -44.7% See commit ("perf: add a comparison test of grep regex engines", 2017-04-19) for details on the machine the above test run was executed on. Here HEAD~2 is git with PCRE v1 without JIT, HEAD~ is PCRE v1 with JIT, and HEAD is PCRE v2 (also with JIT). See previous commits of mine mentioning p7820-grep-engines.sh for more details on the test setup. For ease of readability, a different run just of HEAD~ (PCRE v1 with JIT v.s. PCRE v2), again with just the /perl/ tests shown: [...] Test HEAD~ HEAD ---------------------------------------------------------------------------------------- 7820.3: perl grep 'how.to' 0.21(0.42+0.52) 0.21(0.31+0.58) +0.0% 7820.7: perl grep '^how to' 0.25(0.65+0.50) 0.20(0.31+0.57) -20.0% 7820.11: perl grep '[how] to' 0.30(0.90+0.50) 0.23(0.46+0.53) -23.3% 7820.15: perl grep '(e.t[^ ]*|v.ry) rare' 0.30(1.19+0.38) 0.23(0.51+0.51) -23.3% 7820.19: perl grep 'm(ú|u)lt.b(æ|y)te' 0.27(0.84+0.48) 0.21(0.34+0.57) -22.2% I.e. the two are either neck-to-neck, but PCRE v2 usually pulls ahead, when it does it's around 20% faster. A brief note on thread safety: As noted in pcre2api(3) & pcre2jit(3) the compiled pattern can be shared between threads, but not some of the JIT context, however the grep threading support does all pattern & JIT compilation in separate threads, so this code doesn't need to concern itself with thread safety. See commit 63e7e9d8b6 ("git-grep: Learn PCRE", 2011-05-09) for the initial addition of PCRE v1. This change follows some of the same patterns it did (and which were discussed on list at the time), e.g. mocking up types with typedef instead of ifdef-ing them out when USE_LIBPCRE2 isn't defined. This adds some trivial memory use to the program, but makes the code look nicer. 1. https://lists.exim.org/lurker/message/20150105.162835.0666407a.en.html 2. https://lists.exim.org/lurker/thread/20170419.172322.833ee099.en.html Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-01 18:20:56 +00:00
uint32_t pcre2_jit_on;
unsigned fixed:1;
unsigned is_fixed:1;
unsigned ignore_case:1;
unsigned word_regexp:1;
};
enum grep_expr_node {
GREP_NODE_ATOM,
GREP_NODE_NOT,
GREP_NODE_AND,
GREP_NODE_TRUE,
GREP_NODE_OR
};
enum grep_pattern_type {
GREP_PATTERN_TYPE_UNSPECIFIED = 0,
GREP_PATTERN_TYPE_BRE,
GREP_PATTERN_TYPE_ERE,
GREP_PATTERN_TYPE_FIXED,
GREP_PATTERN_TYPE_PCRE
};
struct grep_expr {
enum grep_expr_node node;
unsigned hit;
union {
struct grep_pat *atom;
struct grep_expr *unary;
struct {
struct grep_expr *left;
struct grep_expr *right;
} binary;
} u;
};
struct grep_opt {
struct grep_pat *pattern_list;
struct grep_pat **pattern_tail;
struct grep_pat *header_list;
struct grep_pat **header_tail;
struct grep_expr *pattern_expression;
/*
* NEEDSWORK: See if we can remove this field, because the repository
* should probably be per-source. That is, grep.c functions using this
* field should probably start using "repo" in "struct grep_source"
* instead.
*
* This is potentially the cause of at least one bug - "git grep"
grep: demonstrate bug with textconv attributes and submodules In some circumstances, "git grep --textconv --recurse-submodules" ignores the textconv attributes from the submodules and erroneously applies the attributes defined in the superproject on the submodules' files. The textconv cache is also saved on the superproject, even for submodule objects. A fix for these problems will probably require at least three changes: - Some textconv and attributes functions (as well as their callees) will have to be adjusted to work with arbitrary repositories. Note that "fill_textconv()", for example, already receives a "struct repository" but it writes the textconv cache using "write_loose_object()", which implicitly works on "the_repository". - grep.c functions will have to call textconv/userdiff routines passing the "repo" field from "struct grep_source" instead of the one from "struct grep_opt". The latter always points to "the_repository" on "git grep" executions (see its initialization in builtin/grep.c), but the former points to the correct repository that each source (an object, file, or buffer) comes from. - "userdiff_find_by_path()" might need to use a different attributes stack for each repository it works on or reset its internal static stack when the repository is changed throughout the calls. For now, let's add some tests to demonstrate these problems, and also update a NEEDSWORK comment in grep.h that mentions this bug to reference the added tests. Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-29 12:24:25 +00:00
* using the textconv attributes from the superproject on the
* submodules. See the failing "git grep --textconv" tests in
* t7814-grep-recurse-submodules.sh for more information.
*/
struct repository *repo;
int linenum;
int columnnum;
int invert;
int ignore_case;
int status_only;
int name_only;
int unmatch_name_only;
int count;
int word_regexp;
int all_match;
int no_body_match;
int body_hit;
#define GREP_BINARY_DEFAULT 0
#define GREP_BINARY_NOMATCH 1
#define GREP_BINARY_TEXT 2
int binary;
int allow_textconv;
int use_reflog_filter;
int relative;
int pathname;
int null_following_name;
int only_matching;
int color;
int max_depth;
int funcname;
int funcbody;
int extended_regexp_option;
enum grep_pattern_type pattern_type_option;
int ignore_locale;
char colors[NR_GREP_COLORS][COLOR_MAXLEN];
unsigned pre_context;
unsigned post_context;
unsigned last_shown;
int show_hunk_mark;
int file_break;
int heading;
int max_count;
void *priv;
void (*output)(struct grep_opt *opt, const void *data, size_t size);
void *output_priv;
};
grep API: call grep_config() after grep_init() The grep_init() function used the odd pattern of initializing the passed-in "struct grep_opt" with a statically defined "grep_defaults" struct, which would be modified in-place when we invoked grep_config(). So we effectively (b) initialized config, (a) then defaults, (c) followed by user options. Usually those are ordered as "a", "b" and "c" instead. As the comments being removed here show the previous behavior needed to be carefully explained as we'd potentially share the populated configuration among different instances of grep_init(). In practice we didn't do that, but now that it can't be a concern anymore let's remove those comments. This does not change the behavior of any of the configuration variables or options. That would have been the case if we didn't move around the grep_config() call in "builtin/log.c". But now that we call "grep_config" after "git_log_config" and "git_format_config" we'll need to pass in the already initialized "struct grep_opt *". See 6ba9bb76e02 (grep: copy struct in one fell swoop, 2020-11-29) and 7687a0541e0 (grep: move the configuration parsing logic to grep.[ch], 2012-10-09) for the commits that added the comments. The memcpy() pattern here will be optimized away and follows the convention of other *_init() functions. See 5726a6b4012 (*.c *_init(): define in terms of corresponding *_INIT macro, 2021-07-01). Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-02-16 00:00:36 +00:00
#define GREP_OPT_INIT { \
.relative = 1, \
.pathname = 1, \
.max_depth = -1, \
.max_count = -1, \
grep API: call grep_config() after grep_init() The grep_init() function used the odd pattern of initializing the passed-in "struct grep_opt" with a statically defined "grep_defaults" struct, which would be modified in-place when we invoked grep_config(). So we effectively (b) initialized config, (a) then defaults, (c) followed by user options. Usually those are ordered as "a", "b" and "c" instead. As the comments being removed here show the previous behavior needed to be carefully explained as we'd potentially share the populated configuration among different instances of grep_init(). In practice we didn't do that, but now that it can't be a concern anymore let's remove those comments. This does not change the behavior of any of the configuration variables or options. That would have been the case if we didn't move around the grep_config() call in "builtin/log.c". But now that we call "grep_config" after "git_log_config" and "git_format_config" we'll need to pass in the already initialized "struct grep_opt *". See 6ba9bb76e02 (grep: copy struct in one fell swoop, 2020-11-29) and 7687a0541e0 (grep: move the configuration parsing logic to grep.[ch], 2012-10-09) for the commits that added the comments. The memcpy() pattern here will be optimized away and follows the convention of other *_init() functions. See 5726a6b4012 (*.c *_init(): define in terms of corresponding *_INIT macro, 2021-07-01). Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-02-16 00:00:36 +00:00
.pattern_type_option = GREP_PATTERN_TYPE_UNSPECIFIED, \
.colors = { \
[GREP_COLOR_CONTEXT] = "", \
[GREP_COLOR_FILENAME] = GIT_COLOR_MAGENTA, \
[GREP_COLOR_FUNCTION] = "", \
[GREP_COLOR_LINENO] = GIT_COLOR_GREEN, \
[GREP_COLOR_COLUMNNO] = GIT_COLOR_GREEN, \
[GREP_COLOR_MATCH_CONTEXT] = GIT_COLOR_BOLD_RED, \
[GREP_COLOR_MATCH_SELECTED] = GIT_COLOR_BOLD_RED, \
[GREP_COLOR_SELECTED] = "", \
[GREP_COLOR_SEP] = GIT_COLOR_CYAN, \
}, \
.only_matching = 0, \
.color = -1, \
.output = std_output, \
}
config: add ctx arg to config_fn_t Add a new "const struct config_context *ctx" arg to config_fn_t to hold additional information about the config iteration operation. config_context has a "struct key_value_info kvi" member that holds metadata about the config source being read (e.g. what kind of config source it is, the filename, etc). In this series, we're only interested in .kvi, so we could have just used "struct key_value_info" as an arg, but config_context makes it possible to add/adjust members in the future without changing the config_fn_t signature. We could also consider other ways of organizing the args (e.g. moving the config name and value into config_context or key_value_info), but in my experiments, the incremental benefit doesn't justify the added complexity (e.g. a config_fn_t will sometimes invoke another config_fn_t but with a different config value). In subsequent commits, the .kvi member will replace the global "struct config_reader" in config.c, making config iteration a global-free operation. It requires much more work for the machinery to provide meaningful values of .kvi, so for now, merely change the signature and call sites, pass NULL as a placeholder value, and don't rely on the arg in any meaningful way. Most of the changes are performed by contrib/coccinelle/config_fn_ctx.pending.cocci, which, for every config_fn_t: - Modifies the signature to accept "const struct config_context *ctx" - Passes "ctx" to any inner config_fn_t, if needed - Adds UNUSED attributes to "ctx", if needed Most config_fn_t instances are easily identified by seeing if they are called by the various config functions. Most of the remaining ones are manually named in the .cocci patch. Manual cleanups are still needed, but the majority of it is trivial; it's either adjusting config_fn_t that the .cocci patch didn't catch, or adding forward declarations of "struct config_context ctx" to make the signatures make sense. The non-trivial changes are in cases where we are invoking a config_fn_t outside of config machinery, and we now need to decide what value of "ctx" to pass. These cases are: - trace2/tr2_cfg.c:tr2_cfg_set_fl() This is indirectly called by git_config_set() so that the trace2 machinery can notice the new config values and update its settings using the tr2 config parsing function, i.e. tr2_cfg_cb(). - builtin/checkout.c:checkout_main() This calls git_xmerge_config() as a shorthand for parsing a CLI arg. This might be worth refactoring away in the future, since git_xmerge_config() can call git_default_config(), which can do much more than just parsing. Handle them by creating a KVI_INIT macro that initializes "struct key_value_info" to a reasonable default, and use that to construct the "ctx" arg. Signed-off-by: Glen Choo <chooglen@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-06-28 19:26:22 +00:00
struct config_context;
int grep_config(const char *var, const char *value,
const struct config_context *ctx, void *data);
built-ins: trust the "prefix" from run_builtin() Change code in "builtin/grep.c" and "builtin/ls-tree.c" to trust the "prefix" passed from "run_builtin()". The "prefix" we get from setup.c is either going to be NULL or a string of length >0, never "". So we can drop the "prefix && *prefix" checks added for "builtin/grep.c" in 0d042fecf2f (git-grep: show pathnames relative to the current directory, 2006-08-11), and for "builtin/ls-tree.c" in a69dd585fca (ls-tree: chomp leading directories when run from a subdirectory, 2005-12-23). As seen in code in revision.c that was added in cd676a51367 (diff --relative: output paths as relative to the current subdirectory, 2008-02-12) we already have existing code that does away with this assertion. This makes it easier to reason about a subsequent change to the "prefix_length" code in grep.c in a subsequent commit, and since we're going to the trouble of doing that let's leave behind an assert() to promise this to any future callers. For "builtin/grep.c" it would be painful to pass the "prefix" down the callchain of: cmd_grep -> grep_tree -> grep_submodule -> grep_cache -> grep_oid -> grep_source_name So for the code that needs it in grep_source_name() let's add a "grep_prefix" variable similar to the existing "ls_tree_prefix". While at it let's move the code in cmd_ls_tree() around so that we assign to the "ls_tree_prefix" right after declaring the variables, and stop assigning to "prefix". We only subsequently used that variable later in the function after clobbering it. Let's just use our own "grep_prefix" instead. Let's also add an assert() in git.c, so that we'll make this promise about the "prefix" to any current and future callers, as well as to any readers of the code. Code history: * The strlen() in "grep.c" hasn't been used since 493b7a08d80 (grep: accept relative paths outside current working directory, 2009-09-05). When that code was added in 0d042fecf2f (git-grep: show pathnames relative to the current directory, 2006-08-11) we used the length. But since 493b7a08d80 we haven't used it for anything except a boolean check that we could have done on the "prefix" member itself. Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-02-16 00:00:34 +00:00
void grep_init(struct grep_opt *, struct repository *repo);
void append_grep_pat(struct grep_opt *opt, const char *pat, size_t patlen, const char *origin, int no, enum grep_pat_token t);
void append_grep_pattern(struct grep_opt *opt, const char *pat, const char *origin, int no, enum grep_pat_token t);
void append_header_grep_pattern(struct grep_opt *, enum grep_header_field, const char *);
void compile_grep_patterns(struct grep_opt *opt);
void free_grep_patterns(struct grep_opt *opt);
int grep_buffer(struct grep_opt *opt, const char *buf, unsigned long size);
/* The field parameter is only used to filter header patterns
* (where appropriate). If filtering isn't desirable
* GREP_HEADER_FIELD_MAX should be supplied.
*/
int grep_next_match(struct grep_opt *opt,
const char *bol, const char *eol,
enum grep_context ctx, regmatch_t *pmatch,
enum grep_header_field field, int eflags);
struct grep_source {
char *name;
enum grep_source_type {
GREP_SOURCE_OID,
GREP_SOURCE_FILE,
GREP_SOURCE_BUF,
} type;
void *identifier;
struct repository *repo; /* if GREP_SOURCE_OID */
const char *buf;
unsigned long size;
char *path; /* for attribute lookups */
struct userdiff_driver *driver;
};
void grep_source_init_file(struct grep_source *gs, const char *name,
const char *path);
void grep_source_init_oid(struct grep_source *gs, const char *name,
const char *path, const struct object_id *oid,
struct repository *repo);
void grep_source_clear_data(struct grep_source *gs);
void grep_source_clear(struct grep_source *gs);
void grep_source_load_driver(struct grep_source *gs,
struct index_state *istate);
int grep_source(struct grep_opt *opt, struct grep_source *gs);
struct grep_opt *grep_opt_dup(const struct grep_opt *opt);
/*
* Mutex used around access to the attributes machinery if
* opt->use_threads. Must be initialized/destroyed by callers!
*/
grep: make locking flag global The low-level grep code traditionally didn't care about threading, as it doesn't do any threading itself and didn't call out to other non-thread-safe code. That changed with 0579f91 (grep: enable threading with -p and -W using lazy attribute lookup, 2011-12-12), which pushed the lookup of funcname attributes (which is not thread-safe) into the low-level grep code. As a result, the low-level code learned about a new global "grep_attr_mutex" to serialize access to the attribute code. A multi-threaded caller (e.g., builtin/grep.c) is expected to initialize the mutex and set "use_threads" in the grep_opt structure. The low-level code only uses the lock if use_threads is set. However, putting the use_threads flag into the grep_opt struct is not the most logical place. Whether threading is in use is not something that matters for each call to grep_buffer, but is instead global to the whole program (i.e., if any thread is doing multi-threaded grep, every other thread, even if it thinks it is doing its own single-threaded grep, would need to use the locking). In practice, this distinction isn't a problem for us, because the only user of multi-threaded grep is "git-grep", which does nothing except call grep. This patch turns the opt->use_threads flag into a global flag. More important than the nit-picking semantic argument above is that this means that the locking functions don't need to actually have access to a grep_opt to know whether to lock. Which in turn can make adding new locks simpler, as we don't need to pass around a grep_opt. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-02-02 08:18:29 +00:00
extern int grep_use_locks;
extern pthread_mutex_t grep_attr_mutex;
#endif