Commit Graph

89 Commits

Author SHA1 Message Date
Ævar Arnfjörð Bjarmason
34489239d0 grep: stop "using" a custom JIT stack with PCRE v2
As reported in [1] the code I added in 94da9193a6 ("grep: add support
for PCRE v2", 2017-06-01) to use a custom JIT stack has never
worked. It was incorrectly copy/pasted from code I added in
fbaceaac47 ("grep: add support for the PCRE v1 JIT API", 2017-05-25),
which did work.

Thus our intention of starting with 1 byte of stack at a maximum of 1
MB didn't happen, we'd always use the 32 KB stack provided by PCRE
v2's jit_machine_stack_exec()[2]. The reason I allocated a custom
stack at all was this advice in pcrejit(3) (same in pcre2jit(3)):

    "By default, it uses 32KiB on the machine stack. However, some
    large or complicated patterns need more than this"

Since we've haven't had any reports of users running into
PCRE2_ERROR_JIT_STACKLIMIT in the wild I think we can safely assume
that we can just use the library defaults instead and drop this
code. This won't change with the wider use of PCRE v2 in
ed0479ce3d ("Merge branch 'ab/no-kwset' into next", 2019-07-15), a
fixed string search is not a "large or complicated pattern".

For good measure I ran the performance test noted in 94da9193a6,
although the command is simpler now due to my 0f50c8e32c ("Makefile:
remove the NO_R_TO_GCC_LINKER flag", 2019-05-17):

    GIT_PERF_REPEAT_COUNT=30 GIT_PERF_LARGE_REPO=~/g/linux GIT_PERF_MAKE_OPTS='-j8 USE_LIBPCRE2=Y CFLAGS=-O3 LIBPCREDIR=/home/avar/g/pcre2/inst' ./run HEAD~ HEAD p7820-grep-engines.sh

Just the /perl/ results are:

    Test                                            HEAD~             HEAD
    ---------------------------------------------------------------------------------------
    7820.3: perl grep 'how.to'                      0.17(0.27+0.65)   0.17(0.24+0.68) +0.0%
    7820.7: perl grep '^how to'                     0.16(0.23+0.66)   0.16(0.23+0.67) +0.0%
    7820.11: perl grep '[how] to'                   0.18(0.35+0.62)   0.18(0.33+0.65) +0.0%
    7820.15: perl grep '(e.t[^ ]*|v.ry) rare'       0.17(0.45+0.54)   0.17(0.49+0.50) +0.0%
    7820.19: perl grep 'm(ú|u)lt.b(æ|y)te'          0.16(0.33+0.58)   0.16(0.29+0.62) +0.0%

So, as expected there's no change, and running with valgrind reveals
that we have fewer allocations now.

As noted in [3] there are known regexes that will fail with the lower
stack limit, the way GNU grep fixed it is interesting, although I
believe the implementation is overly verbose, they could make PCRE v2
handle that gradual re-allocation, that's what min/max memory is
for.

So we might end up bringing this back, I'm more inclined to just kick
such cases upstairs to PCRE maintainers as a bug, perhaps they'll add
some overall "just allocate more then" flag to make this easier. In
any case there's no functional change here, we didn't have a custom
stack, so let's apply this first, we can always revert it later.

1. https://public-inbox.org/git/20190721194052.15440-1-carenas@gmail.com/
2. I didn't really intend to start with 1 byte, looking at the PCRE v2
   code again what happened is that I cargo-culted some of PCRE v2's
   own test code which was meant to test re-allocations. It's more
   sane to start with say 32 KB with a max of 1 MB, as pcre2grep.c
   does.
3. https://public-inbox.org/git/CAPUEspjj+fG8QDmf=bZXktfpLgkgiu34HTjKLhm-cmEE04FE-A@mail.gmail.com/

Reported-by: Carlo Marcelo Arenas Belón <carenas@gmail.com>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-07-26 13:56:40 -07:00
Ævar Arnfjörð Bjarmason
48de2a768c grep: remove the kwset optimization
A later change will replace this optimization with optimistic use of
PCRE v2. I'm completely removing it as an intermediate step, as
opposed to replacing it with PCRE v2, to demonstrate that no grep
semantics depend on this (or any other) optimization for the fixed
backend anymore.

For now this is mostly (but not entirely) a performance regression, as
shown by this hacky one-liner:

    for opt in '' ' -i'
        do
        GIT_PERF_7821_GREP_OPTS=$opt GIT_PERF_REPEAT_COUNT=10 GIT_PERF_LARGE_REPO=~/g/linux GIT_PERF_MAKE_OPTS='-j8 CFLAGS=-O3 USE_LIBPCRE=YesPlease' ./run origin/master HEAD -- p7821-grep-engines-fixed.sh
    done &&
    for opt in '' ' -i'
        do GIT_PERF_4221_LOG_OPTS=$opt GIT_PERF_REPEAT_COUNT=10 GIT_PERF_LARGE_REPO=~/g/linux GIT_PERF_MAKE_OPTS='-j8 CFLAGS=-O3 USE_LIBPCRE=YesPlease' ./run origin/master HEAD -- p4221-log-grep-engines-fixed.sh
    done

Which produces:

plain grep:

    Test                             origin/master     HEAD
    -------------------------------------------------------------------------
    7821.1: fixed grep int           0.55(1.60+0.63)   0.82(3.11+0.51) +49.1%
    7821.2: basic grep int           0.62(1.68+0.49)   0.85(3.02+0.52) +37.1%
    7821.3: extended grep int        0.61(1.63+0.53)   0.91(3.09+0.44) +49.2%
    7821.4: perl grep int            0.55(1.60+0.57)   0.41(0.93+0.57) -25.5%
    7821.6: fixed grep uncommon      0.20(0.50+0.44)   0.35(1.27+0.42) +75.0%
    7821.7: basic grep uncommon      0.20(0.49+0.45)   0.35(1.29+0.41) +75.0%
    7821.8: extended grep uncommon   0.20(0.45+0.48)   0.35(1.25+0.44) +75.0%
    7821.9: perl grep uncommon       0.20(0.53+0.41)   0.16(0.24+0.49) -20.0%
    7821.11: fixed grep æ            0.35(1.27+0.40)   0.25(0.82+0.39) -28.6%
    7821.12: basic grep æ            0.35(1.28+0.38)   0.25(0.75+0.44) -28.6%
    7821.13: extended grep æ         0.36(1.21+0.46)   0.25(0.86+0.35) -30.6%
    7821.14: perl grep æ             0.35(1.33+0.34)   0.16(0.26+0.47) -54.3%

grep with -i:

    Test                                origin/master     HEAD
    -----------------------------------------------------------------------------
    7821.1: fixed grep -i int           0.61(1.84+0.64)   1.11(4.12+0.64) +82.0%
    7821.2: basic grep -i int           0.72(1.86+0.57)   1.15(4.48+0.49) +59.7%
    7821.3: extended grep -i int        0.94(1.83+0.60)   1.53(4.12+0.58) +62.8%
    7821.4: perl grep -i int            0.66(1.82+0.59)   0.55(1.08+0.58) -16.7%
    7821.6: fixed grep -i uncommon      0.21(0.51+0.44)   0.44(1.74+0.34) +109.5%
    7821.7: basic grep -i uncommon      0.21(0.55+0.41)   0.44(1.72+0.40) +109.5%
    7821.8: extended grep -i uncommon   0.21(0.57+0.39)   0.42(1.64+0.45) +100.0%
    7821.9: perl grep -i uncommon       0.21(0.48+0.48)   0.17(0.30+0.45) -19.0%
    7821.11: fixed grep -i æ            0.25(0.73+0.45)   0.25(0.75+0.45) +0.0%
    7821.12: basic grep -i æ            0.25(0.71+0.49)   0.26(0.77+0.44) +4.0%
    7821.13: extended grep -i æ         0.25(0.75+0.44)   0.25(0.74+0.46) +0.0%
    7821.14: perl grep -i æ             0.17(0.26+0.48)   0.16(0.20+0.52) -5.9%

plain log:

    Test                                     origin/master     HEAD
    ---------------------------------------------------------------------------------
    4221.1: fixed log --grep='int'           7.31(7.06+0.21)   8.11(7.85+0.20) +10.9%
    4221.2: basic log --grep='int'           7.30(6.94+0.27)   8.16(7.89+0.19) +11.8%
    4221.3: extended log --grep='int'        7.34(7.05+0.21)   8.08(7.76+0.25) +10.1%
    4221.4: perl log --grep='int'            7.27(6.94+0.24)   7.05(6.76+0.25) -3.0%
    4221.6: fixed log --grep='uncommon'      6.97(6.62+0.32)   7.86(7.51+0.30) +12.8%
    4221.7: basic log --grep='uncommon'      7.05(6.69+0.29)   7.89(7.60+0.28) +11.9%
    4221.8: extended log --grep='uncommon'   6.89(6.56+0.32)   7.99(7.66+0.24) +16.0%
    4221.9: perl log --grep='uncommon'       7.02(6.66+0.33)   6.97(6.54+0.36) -0.7%
    4221.11: fixed log --grep='æ'            7.37(7.03+0.33)   7.67(7.30+0.31) +4.1%
    4221.12: basic log --grep='æ'            7.41(7.00+0.31)   7.60(7.28+0.26) +2.6%
    4221.13: extended log --grep='æ'         7.35(6.96+0.38)   7.73(7.31+0.34) +5.2%
    4221.14: perl log --grep='æ'             7.43(7.10+0.32)   6.95(6.61+0.27) -6.5%

log with -i:

    Test                                        origin/master     HEAD
    ------------------------------------------------------------------------------------
    4221.1: fixed log -i --grep='int'           7.40(7.05+0.23)   8.66(8.38+0.20) +17.0%
    4221.2: basic log -i --grep='int'           7.39(7.09+0.23)   8.67(8.39+0.20) +17.3%
    4221.3: extended log -i --grep='int'        7.29(6.99+0.26)   8.69(8.31+0.26) +19.2%
    4221.4: perl log -i --grep='int'            7.42(7.16+0.21)   7.14(6.80+0.24) -3.8%
    4221.6: fixed log -i --grep='uncommon'      6.94(6.58+0.35)   8.43(8.04+0.30) +21.5%
    4221.7: basic log -i --grep='uncommon'      6.95(6.62+0.31)   8.34(7.93+0.32) +20.0%
    4221.8: extended log -i --grep='uncommon'   7.06(6.75+0.25)   8.32(7.98+0.31) +17.8%
    4221.9: perl log -i --grep='uncommon'       6.96(6.69+0.26)   7.04(6.64+0.32) +1.1%
    4221.11: fixed log -i --grep='æ'            7.92(7.55+0.33)   7.86(7.44+0.34) -0.8%
    4221.12: basic log -i --grep='æ'            7.88(7.49+0.32)   7.84(7.46+0.34) -0.5%
    4221.13: extended log -i --grep='æ'         7.91(7.51+0.32)   7.87(7.48+0.32) -0.5%
    4221.14: perl log -i --grep='æ'             7.01(6.59+0.35)   6.99(6.64+0.28) -0.3%

Some of those, as noted in [1] are because PCRE is faster at finding
fixed strings. This looks bad for some engines, but in the next change
we'll optimistically use PCRE v2 for all of these, so it'll look
better.

1. https://public-inbox.org/git/87v9x793qi.fsf@evledraar.gmail.com/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-07-01 14:33:14 -07:00
Ævar Arnfjörð Bjarmason
44570188a0 grep: don't use PCRE2?_UTF8 with "log --encoding=<non-utf8>"
Fix a bug introduced in 18547aacf5 ("grep/pcre: support utf-8",
2016-06-25) that was missed due to a blindspot in our tests, as
discussed in the previous commit. I then blindly copied the same bug
in 94da9193a6 ("grep: add support for PCRE v2", 2017-06-01) when
adding the PCRE v2 code.

We should not tell PCRE that we're processing UTF-8 just because we're
dealing with non-ASCII. In the case of e.g. "log --encoding=<...>"
under is_utf8_locale() the haystack might be in ISO-8859-1, and the
needle might be in a non-UTF-8 encoding.

Maybe we should be more strict here and die earlier? Should we also be
converting the needle to the encoding in question, and failing if it's
not a string that's valid in that encoding? Maybe.

But for now matching this as non-UTF8 at least has some hope of
producing sensible results, since we know that our default heuristic
of assuming the text to be matched is in the user locale encoding
isn't true when we've explicitly encoded it to be in a different
encoding.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-06-28 09:11:09 -07:00
Denton Liu
554544276a *.[ch]: remove extern from function declarations using spatch
There has been a push to remove extern from function declarations.
Remove some instances of "extern" for function declarations which are
caught by Coccinelle. Note that Coccinelle has some difficulty with
processing functions with `__attribute__` or varargs so some `extern`
declarations are left behind to be dealt with in a future patch.

This was the Coccinelle patch used:

	@@
	type T;
	identifier f;
	@@
	- extern
	  T f(...);

and it was run with:

	$ git ls-files \*.{c,h} |
		grep -v ^compat/ |
		xargs spatch --sp-file contrib/coccinelle/noextern.cocci --in-place

Files under `compat/` are intentionally excluded as some are directly
copied from external sources and we should avoid churning them as much
as possible.

Signed-off-by: Denton Liu <liu.denton@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-05-05 15:20:06 +09:00
Nguyễn Thái Ngọc Duy
4002e87cb2 grep: remove #ifdef NO_PTHREADS
This is a faithful conversion without attempting to improve
anything. That comes later.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-11-05 13:42:11 +09:00
Nguyễn Thái Ngọc Duy
acd00ea049 userdiff.c: remove implicit dependency on the_index
[jc: squashed in missing forward decl in userdiff.h found by Ramsay]

Helped-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-09-21 09:50:58 -07:00
Nguyễn Thái Ngọc Duy
38bbc2ea39 grep.c: remove implicit dependency on the_index
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-09-21 09:48:10 -07:00
Junio C Hamano
87ece7ce11 Merge branch 'tb/grep-only-matching'
"git grep" learned the "--only-matching" option.

* tb/grep-only-matching:
  grep.c: teach 'git grep --only-matching'
  grep.c: extract show_line_header()
2018-08-02 15:30:44 -07:00
Junio C Hamano
d036d667b7 Merge branch 'tb/grep-column'
"git grep" learned the "--column" option that gives not just the
line number but the column number of the hit.

* tb/grep-column:
  contrib/git-jump/git-jump: jump to exact location
  grep.c: add configuration variables to show matched option
  builtin/grep.c: add '--column' option to 'git-grep(1)'
  grep.c: display column number of first match
  grep.[ch]: extend grep_opt to allow showing matched column
  grep.c: expose {,inverted} match column in match_line()
  Documentation/config.txt: camel-case lineNumber for consistency
2018-07-18 12:20:31 -07:00
Taylor Blau
9d8db06eb4 grep.c: teach 'git grep --only-matching'
Teach 'git grep --only-matching', a new option to only print the
matching part(s) of a line.

For instance, a line containing the following (taken from README.md:27):

  (`man gitcvs-migration` or `git help cvs-migration` if git is

Is printed as follows:

  $ git grep --line-number --column --only-matching -e git -- \
    README.md | grep ":27"
  README.md:27:7:git
  README.md:27:16:git
  README.md:27:38:git

The patch works mostly as one would expect, with the exception of a few
considerations that are worth mentioning here.

Like GNU grep, this patch ignores --only-matching when --invert (-v) is
given. There is a sensible answer here, but parity with the behavior of
other tools is preferred.

Because a line might contain more than one match, there are special
considerations pertaining to when to print line headers, newlines, and
how to increment the match column offset. The line header and newlines
are handled as a special case within the main loop to avoid polluting
the surrounding code with conditionals that have large blocks.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-09 14:15:28 -07:00
Taylor Blau
017c0fcfdb grep.[ch]: extend grep_opt to allow showing matched column
To support showing the matched column when calling 'git-grep(1)', teach
'grep_opt' the normal set of options to configure the default behavior
and colorization of this feature.

Now that we have opt->columnnum, use it to disable short-circuiting over
ORs and ANDs so that col and icol are always filled with the earliest
matches on each line. In addition, don't return the first match from
match_line(), for the same reason.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-22 12:59:02 -07:00
Nguyễn Thái Ngọc Duy
fa151dc54d grep: keep all colors in an array
This is more inline with how we handle color slots in other code. It
also allows us to get the list of configurable color slots later.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-29 14:51:28 +09:00
Junio C Hamano
2620b47794 Merge branch 'ab/pcre-v2'
Building with NO_LIBPCRE1_JIT did not disable it, which has been fixed.

* ab/pcre-v2:
  grep: fix NO_LIBPCRE1_JIT to fully disable JIT
2017-11-15 12:14:34 +09:00
Charles Bailey
2fff1e196d grep: fix NO_LIBPCRE1_JIT to fully disable JIT
If you have a pcre1 library which is compiled with JIT enabled then
PCRE_STUDY_JIT_COMPILE will be defined whether or not the
NO_LIBPCRE1_JIT configuration is set.

This means that we enable JIT functionality when calling pcre_study
even if NO_LIBPCRE1_JIT has been explicitly set and we just use plain
pcre_exec later.

Fix this by using own macro (GIT_PCRE_STUDY_JIT_COMPILE) which we set to
PCRE_STUDY_JIT_COMPILE only if NO_LIBPCRE1_JIT is not set and define to
0 otherwise, as before.

Reviewed-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-11-13 12:49:53 +09:00
Brandon Williams
f9ee2fcdfa grep: recurse in-process using 'struct repository'
Convert grep to use 'struct repository' which enables recursing into
submodules to be handled in-process.

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-08-02 14:26:46 -07:00
Ævar Arnfjörð Bjarmason
07a3d41173 grep: remove regflags from the public grep_opt API
Refactor calls to the grep machinery to always pass opt.ignore_case &
opt.extended_regexp_option instead of setting the equivalent regflags
bits.

The bug fixed when making -i work with -P in commit 9e3cbc59d5 ("log:
make --regexp-ignore-case work with --perl-regexp", 2017-05-20) was
really just plastering over the code smell which this change fixes.

The reason for adding the extensive commentary here is that I
discovered some subtle complexity in implementing this that really
should be called out explicitly to future readers.

Before this change we'd rely on the difference between
`extended_regexp_option` and `regflags` to serve as a membrane between
our preliminary parsing of grep.extendedRegexp and grep.patternType,
and what we decided to do internally.

Now that those two are the same thing, it's necessary to unset
`extended_regexp_option` just before we commit in cases where both of
those config variables are set. See 84befcd0a4 ("grep: add a
grep.patternType configuration setting", 2012-08-03) for the code and
documentation related to that.

The explanation of why the if/else branches in
grep_commit_pattern_type() are ordered the way they are exists in that
commit message, but I think it's worth calling this subtlety out
explicitly with a comment for future readers.

Even though grep_commit_pattern_type() is the only caller of
grep_set_pattern_type_option() it's simpler to reset the
extended_regexp_option flag in the latter, since 2/3 branches in the
former would otherwise need to reset it, this way we can do it in one
place.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-30 10:06:24 -07:00
Junio C Hamano
a6f38c109b Merge branch 'bw/object-id'
Conversion from uchar[20] to struct object_id continues.

* bw/object-id: (33 commits)
  diff: rename diff_fill_sha1_info to diff_fill_oid_info
  diffcore-rename: use is_empty_blob_oid
  tree-diff: convert path_appendnew to object_id
  tree-diff: convert diff_tree_paths to struct object_id
  tree-diff: convert try_to_follow_renames to struct object_id
  builtin/diff-tree: cleanup references to sha1
  diff-tree: convert diff_tree_sha1 to struct object_id
  notes-merge: convert write_note_to_worktree to struct object_id
  notes-merge: convert verify_notes_filepair to struct object_id
  notes-merge: convert find_notes_merge_pair_ps to struct object_id
  notes-merge: convert merge_from_diffs to struct object_id
  notes-merge: convert notes_merge* to struct object_id
  tree-diff: convert diff_root_tree_sha1 to struct object_id
  combine-diff: convert find_paths_* to struct object_id
  combine-diff: convert diff_tree_combined to struct object_id
  diff: convert diff_flush_patch_id to struct object_id
  patch-ids: convert to struct object_id
  diff: finish conversion for prepare_temp_file to struct object_id
  diff: convert reuse_worktree_file to struct object_id
  diff: convert fill_filespec to struct object_id
  ...
2017-06-19 12:38:44 -07:00
Brandon Williams
1c41c82bc4 grep: convert to struct object_id
Convert the remaining parts of grep to use struct object_id.

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-02 09:36:06 +09:00
Ævar Arnfjörð Bjarmason
94da9193a6 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>
2017-06-02 08:29:05 +09:00
Ævar Arnfjörð Bjarmason
fb95e2e38d grep: un-break building with PCRE >= 8.32 without --enable-jit
Amend my change earlier in this series ("grep: add support for the
PCRE v1 JIT API", 2017-04-11) to un-break the build on PCRE v1
versions later than 8.31 compiled without --enable-jit.

As explained in that change and a later compatibility change in this
series ("grep: un-break building with PCRE < 8.32", 2017-05-10) the
pcre_jit_exec() function is a faster path to execute the JIT.

Unfortunately there's no compatibility stub for that function compiled
into the library if pcre_config(PCRE_CONFIG_JIT, &ret) would return 0,
and no macro that can be used to check for it, so the only portable
option to support builds without --enable-jit is via a new
NO_LIBPCRE1_JIT=UnfortunatelyYes Makefile option[1].

Another option would be to make the JIT opt-in via
USE_LIBPCRE1_JIT=YesPlease, after all it's not a default option of
PCRE v1.

I think it makes more sense to make it opt-out since even though it's
not a default option, most packagers of PCRE seem to turn it on by
default, with the notable exception of the MinGW package.

Make the MinGW platform work by default by changing the build defaults
to turn on NO_LIBPCRE1_JIT=UnfortunatelyYes. It is the only platform
that turns on USE_LIBPCRE=YesPlease by default, see commit
df5218b4c3 ("config.mak.uname: support MSys2", 2016-01-13) for that
change.

1. "How do I support pcre1 JIT on all
   versions?"  (https://lists.exim.org/lurker/thread/20170601.103148.10253788.en.html)

2. https://github.com/Alexpux/MINGW-packages/blob/master/mingw-w64-pcre/PKGBUILD
   (referenced from "Re: PCRE v2 compile error, was Re: What's cooking
   in git.git (May 2017, #01; Mon, 1)";
   <alpine.DEB.2.20.1705021756530.3480@virtualbox>)

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-02 08:29:05 +09:00
Ævar Arnfjörð Bjarmason
c30cf827a8 grep: un-break building with PCRE < 8.20
Amend my change earlier in this series ("grep: add support for the
PCRE v1 JIT API", 2017-04-11) to un-break the build on PCRE v1
versions earlier than 8.20.

The 8.20 release was the first release to have JIT & pcre_jit_stack in
the headers, so a mock type needs to be provided for it on those
releases.

Now git should compile with all PCRE versions that it supported before
my JIT change.

I've tested it as far back as version 7.5 released on 2008-01-10, once
I got down to version 7.0 it wouldn't build anymore with GCC 7.1.1,
and I couldn't be bothered to anything older than 7.5 as I'm confident
that if the build breaks on those older versions it's not because of
my JIT change.

See the "un-break" change in this series ("grep: un-break building
with PCRE < 8.32", 2017-05-10) for why this isn't squashed into the
main PCRE JIT commit.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-26 12:59:05 +09:00
Ævar Arnfjörð Bjarmason
e87de7cab4 grep: un-break building with PCRE < 8.32
Amend my change earlier in this series ("grep: add support for the
PCRE v1 JIT API", 2017-04-11) to un-break the build on PCRE v1
versions earlier than 8.32.

The JIT support was added in version 8.20 released on 2011-10-21, but
it wasn't until 8.32 released on 2012-11-30 that the fast code path to
use the JIT via pcre_jit_exec() was added[1] (see also [2]).

This means that versions 8.20 through 8.31 could still use the JIT,
but supporting it on those versions would add to the already verbose
macro soup around JIT support it, and I don't expect that the use-case
of compiling a brand new git against a 5 year old PCRE is particularly
common, and if someone does that they can just get the existing
pre-JIT slow codepath.

So just take the easy way out and disable the JIT on any version older
than 8.32.

The reason this change isn't part of the initial change PCRE JIT
support is to have a cleaner history showing which parts of the
implementation are only used for ancient PCRE versions. This also
makes it easier to revert this change if we ever decide to stop
supporting those old versions.

1. http://www.pcre.org/original/changelog.txt ("28. Introducing a
   native interface for JIT. Through this interface, the
   compiled[...]")
2. https://bugs.exim.org/show_bug.cgi?id=2121

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-26 12:59:05 +09:00
Ævar Arnfjörð Bjarmason
fbaceaac47 grep: add support for the PCRE v1 JIT API
Change the grep PCRE v1 code to use JIT when available. When PCRE
support was initially added in commit 63e7e9d8b6 ("git-grep: Learn
PCRE", 2011-05-09) PCRE had no JIT support, it was integrated into
8.20 released on 2011-10-21.

Enabling JIT support usually improves performance by more than
40%. The pattern compilation times are relatively slower, but those
relative numbers are tiny, and are easily made back in all but the
most trivial cases of grep. Detailed benchmarks & overview of
compilation times is at: http://sljit.sourceforge.net/pcre.html

With this change the difference in a t/perf/p7820-grep-engines.sh run
is, with just the /perl/ tests shown:

    $ GIT_PERF_REPEAT_COUNT=30 GIT_PERF_LARGE_REPO=~/g/linux GIT_PERF_MAKE_OPTS='-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~ HEAD p7820-grep-engines.sh
    Test                                           HEAD~             HEAD
    ---------------------------------------------------------------------------------------
    7820.3: perl grep 'how.to'                      0.35(1.11+0.43)   0.23(0.42+0.46) -34.3%
    7820.7: perl grep '^how to'                     0.64(2.71+0.36)   0.27(0.66+0.44) -57.8%
    7820.11: perl grep '[how] to'                   0.63(2.51+0.42)   0.33(0.98+0.39) -47.6%
    7820.15: perl grep '(e.t[^ ]*|v.ry) rare'       1.17(5.61+0.35)   0.34(1.08+0.46) -70.9%
    7820.19: perl grep 'm(ú|u)lt.b(æ|y)te'          0.43(1.52+0.44)   0.30(0.88+0.42) -30.2%

The conditional support for JIT is implemented as suggested in the
pcrejit(3) man page. E.g. defining PCRE_STUDY_JIT_COMPILE to 0 if it's
not present.

The implementation is relatively verbose because even if
PCRE_CONFIG_JIT is defined only a call to pcre_config() can determine
if the JIT is available, and if so the faster pcre_jit_exec() function
should be called instead of pcre_exec(), and a different (but not
complimentary!) function needs to be called to free pcre1_extra_info.

There's no graceful fallback if pcre_jit_stack_alloc() fails under
PCRE_CONFIG_JIT, instead the program will simply abort. I don't think
this is worth handling gracefully, it'll only fail in cases where
malloc() doesn't work, in which case we're screwed anyway.

That there's no assignment of `p->pcre1_jit_on = 0` when
PCRE_CONFIG_JIT isn't defined isn't a bug. The create_grep_pat()
function allocates the grep_pat allocates it with calloc(), so it's
guaranteed to be 0 when PCRE_CONFIG_JIT isn't defined.

I you're bisecting and find this change, check that your PCRE isn't
older than 8.32. This change intentionally broke really old versions
of PCRE, but that's fixed in follow-up commits.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-26 12:59:05 +09:00
Ævar Arnfjörð Bjarmason
6d4b5747f0 grep: change internal *pcre* variable & function names to be *pcre1*
Change the internal PCRE variable & function names to have a "1"
suffix. This is for preparation for libpcre2 support, where having
non-versioned names would be confusing.

An earlier change in this series ("grep: change the internal PCRE
macro names to be PCRE1", 2017-04-07) elaborates on the motivations
behind this change.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-26 12:52:37 +09:00
Ævar Arnfjörð Bjarmason
3485bea157 grep: change the internal PCRE macro names to be PCRE1
Change the internal USE_LIBPCRE define, & build options flag to use a
naming convention ending in PCRE1, without changing the long-standing
USE_LIBPCRE Makefile flag which enables this code.

This is for preparation for libpcre2 support where having things like
USE_LIBPCRE and USE_LIBPCRE2 in any more places than we absolutely
need to for backwards compatibility with old Makefile arguments would
be confusing.

In some ways it would be better to change everything that now uses
USE_LIBPCRE to use USE_LIBPCRE1, and to make specifying
USE_LIBPCRE (or --with-pcre) an error. This would impose a one-time
burden on packagers of git to s/USE_LIBPCRE/USE_LIBPCRE1/ in their
build scripts.

However I'd like to leave the door open to making
USE_LIBPCRE=YesPlease eventually mean USE_LIBPCRE2=YesPlease,
i.e. once PCRE v2 is ubiquitous enough that it makes sense to make it
the default.

This code and the USE_LIBPCRE Makefile argument was added in commit
63e7e9d8b6 ("git-grep: Learn PCRE", 2011-05-09). At the time there was
no indication that the PCRE project would release an entirely new &
incompatible API around 3 years later.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-26 12:52:37 +09:00
Brandon Williams
4538eef564 grep: add submodules as a grep source type
Add `GREP_SOURCE_SUBMODULE` as a grep_source type and cases for this new
type in the various switch statements in grep.c.

When initializing a grep_source with type `GREP_SOURCE_SUBMODULE` the
identifier can either be NULL (to indicate that the working tree will be
used) or a SHA1 (the REV of the submodule to be grep'd).  If the
identifier is a SHA1 then we want to fall through to the
`GREP_SOURCE_SHA1` case to handle the copying of the SHA1.

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-12-22 11:47:33 -08:00
Junio C Hamano
b422d99658 Merge branch 'jc/grep-commandline-vs-configuration'
"git -c grep.patternType=extended log --basic-regexp" misbehaved
because the internal API to access the grep machinery was not
designed well.

* jc/grep-commandline-vs-configuration:
  grep: further simplify setting the pattern type
2016-08-04 14:39:18 -07:00
Junio C Hamano
8465541e8c grep: further simplify setting the pattern type
When c5c31d33 (grep: move pattern-type bits support to top-level
grep.[ch], 2012-10-03) introduced grep_commit_pattern_type() helper
function, the intention was to allow the users of grep API to having
to fiddle only with .pattern_type_option (which can be set to "fixed",
"basic", "extended", and "pcre"), and then immediately before compiling
the pattern strings for use, call grep_commit_pattern_type() to have
it prepare various bits in the grep_opt structure (like .fixed,
.regflags, etc.).

However, grep_set_pattern_type_option() helper function the grep API
internally uses were left as an external function by mistake.  This
function shouldn't have been made callable by the users of the API.

Later when the grep API was used in revision traversal machinery,
the caller then mistakenly started calling the function around
34a4ae55 (log --grep: use the same helper to set -E/-F options as
"git grep", 2012-10-03), instead of setting the .pattern_type_option
field and letting the grep_commit_pattern_type() to take care of the
details.

This caused an unnecessary bug that made a configured
grep.patternType take precedence over the command line options
(e.g. --basic-regexp, --fixed-strings) in "git log" family of
commands.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-07-25 09:16:18 -07:00
Nguyễn Thái Ngọc Duy
9d9babb84d grep/pcre: prepare locale-dependent tables for icase matching
The default tables are usually built with C locale and only suitable
for LANG=C or similar.  This should make case insensitive search work
correctly for all single-byte charsets.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-07-01 12:44:57 -07:00
René Scharfe
79a77109d3 grep: add color.grep.matchcontext and color.grep.matchselected
The config option color.grep.match can be used to specify the highlighting
color for matching strings.  Add the options matchContext and matchSelected
to allow different colors to be specified for matching strings in the
context vs. in selected lines.  This is similar to the ms and mc specifiers
in GNU grep's environment variable GREP_COLORS.

Tests are from Zoltan Klinger's earlier attempt to solve the same
issue in a different way.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-28 10:33:50 -07:00
Jeff King
335ec3bf41 grep: allow to use textconv filters
Recently and not so recently, we made sure that log/grep type operations
use textconv filters when a userfacing diff would do the same:

ef90ab6 (pickaxe: use textconv for -S counting, 2012-10-28)
b1c2f57 (diff_grep: use textconv buffers for add/deleted files, 2012-10-28)
0508fe5 (combine-diff: respect textconv attributes, 2011-05-23)

"git grep" currently does not use textconv filters at all, that is
neither for displaying the match and context nor for the actual grepping,
even when requested by --textconv.

Introduce an option "--textconv" which makes git grep use any configured
textconv filters for grepping and output purposes. It is off by default.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-05-10 10:27:31 -07:00
Antoine Pelisse
3ce3ffb840 fix clang -Wtautological-compare with unsigned enum
Create a GREP_HEADER_FIELD_MIN so we can check that the field value is
sane and silence the clang warning.

Clang warning happens because the enum is unsigned (this is
implementation-defined, and there is no negative fields) and the check
is then tautological.

Signed-off-by: Antoine Pelisse <apelisse@gmail.com>
Signed-off-by: John Keeping <john@keeping.me.uk>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-02-25 07:35:55 -08:00
Jeff King
e034d1bb92 Merge branch 'nd/grep-true-path'
"git grep -e pattern <tree>" asked the attribute system to read
"<tree>:.gitattributes" file in the working tree, which was
nonsense.

* nd/grep-true-path:
  grep: stop looking at random places for .gitattributes
2012-10-29 04:13:16 -04:00
Nguyễn Thái Ngọc Duy
55c61688ea grep: stop looking at random places for .gitattributes
grep searches for .gitattributes using "name" field in struct
grep_source but that field is not real on-disk path name. For example,
"grep pattern rev" fills the field with "rev:path", and Git looks for
.gitattributes in the (non-existent but exploitable) path "rev:path"
instead of "path".

This patch passes real paths down to grep_source_load_driver() when:

 - grep on work tree
 - grep on the index
 - grep a commit (or a tag if it points to a commit)

so that these cases look up .gitattributes at proper paths.
.gitattributes lookup is disabled in all other cases.

Initial-work-by: Jeff King <peff@peff.net>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-10-12 08:24:44 -07:00
Junio C Hamano
c5c31d3381 grep: move pattern-type bits support to top-level grep.[ch]
Switching between -E/-G/-P/-F correctly needs a lot more than just
flipping opt->regflags bit these days, and we have a nice helper
function buried in builtin/grep.c for the sole use of "git grep".

Extract it so that "log --grep" family can also use it.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-10-09 23:21:29 -07:00
Junio C Hamano
7687a0541e grep: move the configuration parsing logic to grep.[ch]
The configuration handling is a library-ish part of this program,
that is not specific to "git grep" command.  It should be reusable
by "log" and others.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-10-09 16:17:50 -07:00
Junio C Hamano
baa6378ff2 log --grep-reflog: reject the option without -g
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-09-29 12:07:04 -07:00
Nguyễn Thái Ngọc Duy
72fd13f71c revision: add --grep-reflog to filter commits by reflog messages
Similar to --author/--committer which filters commits by author and
committer header fields. --grep-reflog adds a fake "reflog" header to
commit and a grep filter to search on that line.

All rules to --author/--committer apply except no timestamp stripping.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-09-29 11:41:14 -07:00
Nguyễn Thái Ngọc Duy
ad4813b3c2 grep: prepare for new header field filter
grep supports only author and committer headers, which have the same
special treatment that later headers may or may not have. Check for
field type and only strip_timestamp() when the field is either author
or committer.

GREP_HEADER_FIELD_MAX is put in the grep_header_field enum to be
calculated automatically, correctly, as long as it's at the end of the
enum.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-09-29 11:40:58 -07:00
Junio C Hamano
3d7535e424 Merge branch 'jc/maint-log-grep-all-match'
Fix a long-standing bug in "git log --grep" when multiple "--grep"
are used together with "--all-match" and "--author" or "--committer".

* jc/maint-log-grep-all-match:
  t7810-grep: test --all-match with multiple --grep and --author options
  t7810-grep: test interaction of multiple --grep and --author options
  t7810-grep: test multiple --author with --all-match
  t7810-grep: test multiple --grep with and without --all-match
  t7810-grep: bring log --grep tests in common form
  grep.c: mark private file-scope symbols as static
  log: document use of multiple commit limiting options
  log --grep/--author: honor --all-match honored for multiple --grep patterns
  grep: show --debug output only once
  grep: teach --debug option to dump the parse tree
2012-09-18 14:37:54 -07:00
Junio C Hamano
07a7d656dd grep.c: mark private file-scope symbols as static
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-09-15 23:35:39 -07:00
Junio C Hamano
17bf35a3c7 grep: teach --debug option to dump the parse tree
Our "grep" allows complex boolean expressions to be formed to match
each individual line with operators like --and, '(', ')' and --not.
Introduce the "--debug" option to show the parse tree to help people
who want to debug and enhance it.

Also "log" learns "--grep-debug" option to do the same.  The command
line parser to the log family is a lot more limited than the general
"git grep" parser, but it has special handling for header matching
(e.g. "--author"), and a parse tree is valuable when working on it.

Note that "--all-match" is *not* any individual node in the parse
tree.  It is an instruction to the evaluator to check all the nodes
in the top-level backbone have matched and reject a document as
non-matching otherwise.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-09-14 10:10:35 -07:00
J Smith
84befcd0a4 grep: add a grep.patternType configuration setting
The grep.extendedRegexp configuration setting enables the -E flag on grep
by default but there are no equivalents for the -G, -F and -P flags.

Rather than adding an additional setting for grep.fooRegexp for current
and future pattern matching options, add a grep.patternType setting that
can accept appropriate values for modifying the default grep pattern
matching behavior. The current values are "basic", "extended", "fixed",
"perl" and "default" for setting -G, -E, -F, -P and the default behavior
respectively.

When grep.patternType is set to a value other than "default", the
grep.extendedRegexp setting is ignored. The value of "default" restores
the current default behavior, including the grep.extendedRegexp
behavior.

Signed-off-by: J Smith <dark.panda@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-08-03 09:58:02 -07:00
Junio C Hamano
2147cb2762 Merge branch 'rs/maint-grep-F' into maint
"git grep -e '$pattern'", unlike the case where the patterns are read from
a file, did not treat individual lines in the given pattern argument as
separate regular expressions as it should.

By René Scharfe
* rs/maint-grep-F:
  grep: stop leaking line strings with -f
  grep: support newline separated pattern list
  grep: factor out do_append_grep_pat()
  grep: factor out create_grep_pat()
2012-06-01 13:01:41 -07:00
Junio C Hamano
fca9e0013e Merge branch 'rs/maint-grep-F'
"git grep -e '$pattern'", unlike the case where the patterns are read from
a file, did not treat individual lines in the given pattern argument as
separate regular expressions as it should.
2012-05-25 12:04:19 -07:00
René Scharfe
526a858a99 grep: support newline separated pattern list
Currently, patterns that contain newline characters don't match anything
when given to git grep.  Regular grep(1) interprets patterns as lists of
newline separated search strings instead.

Implement this functionality by creating and inserting extra grep_pat
structures for patterns consisting of multiple lines when appending to
the pattern lists.  For simplicity, all pattern strings are duplicated.
The original pattern is truncated in place to make it contain only the
first line.

Requested-by: Torne (Richard Coles) <torne@google.com>
Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-05-20 15:25:46 -07:00
Jeff King
41b59bfcb1 grep: respect diff attributes for binary-ness
There is currently no way for users to tell git-grep that a
particular path is or is not a binary file; instead, grep
always relies on its auto-detection (or the user specifying
"-a" to treat all binary-looking files like text).

This patch teaches git-grep to use the same attribute lookup
that is used by git-diff. We could add a new "grep" flag,
but that is unnecessarily complex and unlikely to be useful.
Despite the name, the "-diff" attribute (or "diff=foo" and
the associated diff.foo.binary config option) are really
about describing the contents of the path. It's simply
historical that diff was the only thing that cared about
these attributes in the past.

And if this simple approach turns out to be insufficient, we
still have a backwards-compatible path forward: we can add a
separate "grep" attribute, and fall back to respecting
"diff" if it is unset.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-02-02 10:36:08 -08:00
Jeff King
94ad9d9e07 grep: cache userdiff_driver in grep_source
Right now, grep only uses the userdiff_driver for one thing:
looking up funcname patterns for "-p" and "-W".  As new uses
for userdiff drivers are added to the grep code, we want to
minimize attribute lookups, which can be expensive.

It might seem at first that this would also optimize multiple
lookups when the funcname pattern for a file is needed
multiple times. However, the compiled funcname pattern is
already cached in struct grep_opt's "priv" member, so
multiple lookups are already suppressed.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-02-02 10:36:08 -08:00
Jeff King
c876d6da88 grep: drop grep_buffer's "name" parameter
Before the grep_source interface existed, grep_buffer was
used by two types of callers:

  1. Ones which pulled a file into a buffer, and then wanted
     to supply the file's name for the output (i.e.,
     git grep).

  2. Ones which really just wanted to grep a buffer (i.e.,
     git log --grep).

Callers in set (1) should now be using grep_source. Callers
in set (2) always pass NULL for the "name" parameter of
grep_buffer. We can therefore get rid of this now-useless
parameter.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-02-02 10:36:08 -08:00
Jeff King
e1327023ea grep: refactor the concept of "grep source" into an object
The main interface to the low-level grep code is
grep_buffer, which takes a pointer to a buffer and a size.
This is convenient and flexible (we use it to grep commit
bodies, files on disk, and blobs by sha1), but it makes it
hard to pass extra information about what we are grepping
(either for correctness, like overriding binary
auto-detection, or for optimizations, like lazily loading
blob contents).

Instead, let's encapsulate the idea of a "grep source",
including the buffer, its size, and where the data is coming
from. This is similar to the diff_filespec structure used by
the diff code (unsurprising, since future patches will
implement some of the same optimizations found there).

The diffstat is slightly scarier than the actual patch
content. Most of the modified lines are simply replacing
access to raw variables with their counterparts that are now
in a "struct grep_source". Most of the added lines were
taken from builtin/grep.c, which partially abstracted the
idea of grep sources (for file vs sha1 sources).

Instead of dropping the now-redundant code, this patch
leaves builtin/grep.c using the traditional grep_buffer
interface (which now wraps the grep_source interface). That
makes it easy to test that there is no change of behavior
(yet).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-02-02 10:36:07 -08:00