Commit graph

224 commits

Author SHA1 Message Date
Johannes Schindelin
033abf97fc Replace all die("BUG: ...") calls by BUG() ones
In d8193743e0 (usage.c: add BUG() function, 2017-05-12), a new macro
was introduced to use for reporting bugs instead of die(). It was then
subsequently used to convert one single caller in 588a538ae5
(setup_git_env: convert die("BUG") to BUG(), 2017-05-12).

The cover letter of the patch series containing this patch
(cf 20170513032414.mfrwabt4hovujde2@sigill.intra.peff.net) is not
terribly clear why only one call site was converted, or what the plan
is for other, similar calls to die() to report bugs.

Let's just convert all remaining ones in one fell swoop.

This trick was performed by this invocation:

	sed -i 's/die("BUG: /BUG("/g' $(git grep -l 'die("BUG' \*.c)

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-06 19:06:13 +09:00
brian m. carlson
b4f5aca40e sha1_file: convert read_sha1_file to struct object_id
Convert read_sha1_file to take a pointer to struct object_id and rename
it read_object_file.  Do the same for read_sha1_file_extended.

Convert one use in grep.c to use the new function without any other code
change, since the pointer being passed is a void pointer that is already
initialized with a pointer to struct object_id.  Update the declaration
and definitions of the modified functions, and apply the following
semantic patch to convert the remaining callers:

@@
expression E1, E2, E3;
@@
- read_sha1_file(E1.hash, E2, E3)
+ read_object_file(&E1, E2, E3)

@@
expression E1, E2, E3;
@@
- read_sha1_file(E1->hash, E2, E3)
+ read_object_file(E1, E2, E3)

@@
expression E1, E2, E3, E4;
@@
- read_sha1_file_extended(E1.hash, E2, E3, E4)
+ read_object_file_extended(&E1, E2, E3, E4)

@@
expression E1, E2, E3, E4;
@@
- read_sha1_file_extended(E1->hash, E2, E3, E4)
+ read_object_file_extended(E1, E2, E3, E4)

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-03-14 09:23:50 -07:00
Stefan Beller
75e5e9c3f7 color.h: document and modernize header
Add documentation explaining the functions in color.h.
While at it, migrate the function `color_set` into grep.c,
where the only callers are.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-02-13 10:17:12 -08:00
Junio C Hamano
b3f04e5b4c Merge branch 'ab/pcre2-grep'
"git grep" compiled with libpcre2 sometimes triggered a segfault,
which is being fixed.

* ab/pcre2-grep:
  grep: fix segfault under -P + PCRE2 <=10.30 + (*NO_JIT)
  test-lib: add LIBPCRE1 & LIBPCRE2 prerequisites
2017-12-13 13:28:54 -08:00
Ævar Arnfjörð Bjarmason
a25b908504 grep: fix segfault under -P + PCRE2 <=10.30 + (*NO_JIT)
Fix a bug in the compilation of PCRE2 patterns under JIT (the most
common runtime configuration). Any pattern with a (*NO_JIT) verb would
segfault in any currently released PCRE2 version:

    $ git grep -P '(*NO_JIT)hi.*there'
    Segmentation fault

That this segfaulted was a bug in PCRE2 itself, after reporting it[1]
on pcre-dev it's been fixed in a yet-to-be-released version of
PCRE (presumably released first as 10.31). Now it'll die with:

    $ git grep -P '(*NO_JIT)hi.*there'
    fatal: pcre2_jit_match failed with error code -45: bad JIT option

But the cause of the bug is in our own code dating back to my
94da9193a6 ("grep: add support for PCRE v2", 2017-06-01).

As explained at more length in the comment being added here, it isn't
sufficient to just check pcre2_config() to see whether the JIT should
be used, pcre2_pattern_info() also has to be asked.

This is something I discovered myself when fiddling around with PCRE2
verbs in patterns passed to git. I don't expect that any user of git
has encountered this given the obscurity of passing PCRE2 verbs
through to the library, along with the relative obscurity of (*NO_JIT)
itself.

1. "How am I supposed to use PCRE2 JIT in the face of (*NO_JIT) ?"
   (<CACBZZX5mMqDuWuFmi7sRBp3wH6CFyd-ghACukd=v0NN=rBMnJg@mail.gmail.com> &
    https://lists.exim.org/lurker/thread/20171123.101502.7f0d38ca.en.html)
   on the pcre-dev mailing list

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-11-24 16:12:26 +09:00
René Scharfe
a5dc20b070 grep: show non-empty lines before functions with -W
Non-empty lines before a function definition are most likely comments
for that function and thus relevant.  Include them in function context.

Such a non-empty line might also belong to the preceding function if
there is no separating blank line.  Stop extending the context upwards
also at the next function line to make sure only one extra function body
is shown at most.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-11-21 09:36:06 +09:00
René Scharfe
6653a01bf2 grep: update boundary variable for pre-context
Function context can be bigger than -A/-B/-C context.  To find the
beginning of the combined context we search backwards.  Currently we
check at each loop iteration what we're looking for and determine the
effective upper boundary based on that.

Simplify this a bit by setting the variable "from" to the lowest unshown
line number up front if we're looking for a function line and set it
back to the required -B/-C context line number when we find one.  This
prepares the ground for the next patch; no functional change intended.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-11-21 09:36:06 +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
Junio C Hamano
85c81a74e2 Merge branch 'as/grep-quiet-no-match-exit-code-fix'
"git grep -L" and "git grep --quiet -L" reported different exit
codes; this has been corrected.

* as/grep-quiet-no-match-exit-code-fix:
  git-grep: correct exit code with --quiet and -L
2017-08-23 14:13:12 -07:00
Anthony Sottile
e1f68c66d5 git-grep: correct exit code with --quiet and -L
The handling of `status_only` no longer interferes with the handling of
`unmatch_name_only`.  `--quiet` no longer affects the exit code when using
`-L`/`--files-without-match`.

Signed-off-by: Anthony Sottile <asottile@umich.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-08-17 19:02:23 -07:00
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
1ceababc4c grep: remove redundant REG_NEWLINE when compiling fixed regex
Remove the redundant REG_NEWLINE regcomp() flag from the code that
compiles a fixed-string regular-expression.

The REG_NEWLINE causes metacharacters such as "." to match a newline,
since the basic_regex_quote_buf() function being called here escapes
all metacharacters using REG_NEWLINE is confusing and redundant.

The use of this flag was introduced as an unintended emergent property
of 793dc676e0 ("grep/icase: avoid kwsset when -F is specified",
2016-06-25).

That change amended the existing regflags, which were initialized to
REG_NEWLINE in init_grep_defaults() assuming a subsequent non-fixed
regcomp().

Manual testing reveals that this was always redundant, since no flags
of any use were inherited from opt->regflags even back
then. 793dc676e0 passes all tests with this on top:

    diff --git a/grep.c b/grep.c
    index 627ae3e3e8..89e84ed7fd 100644
    --- a/grep.c
    +++ b/grep.c
    @@ -407,3 +407,3 @@ static void compile_fixed_regexp(struct grep_pat *p, struct grep_opt *opt)
            basic_regex_quote_buf(&sb, p->pattern);
    -       regflags = opt->regflags & ~REG_EXTENDED;
    +       regflags = 0;
            if (opt->ignore_case)

Since this isn't used for anything and never was, remove it to reduce
confusion when reading this code.

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
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
Ævar Arnfjörð Bjarmason
b07ed4e532 grep: remove redundant and verbose re-assignments to 0
Remove the redundant re-assignments of the fixed/pcre1/pcre2 fields to
zero right after the entire struct has been set to zero via
memset(...).

See an earlier related cleanup commit e0b9f8ae09 ("grep: remove
redundant regflags assignments", 2017-05-25) for an explanation of why
the code was structured like this to begin with.

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
Ævar Arnfjörð Bjarmason
885ef80d39 grep: remove redundant "fixed" field re-assignment to 0
Remove the redundant re-assignment of the fixed field to zero right
after the entire struct has been set to zero via memset(...).

Unlike some nearby commits this pattern doesn't date back to the
pattern described in e0b9f8ae09 ("grep: remove redundant regflags
assignments", 2017-05-25), instead it was apparently cargo-culted in
9eceddeec6 ("Use kwset in grep", 2011-08-21).

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
Ævar Arnfjörð Bjarmason
c7e3855112 grep: adjust a redundant grep pattern type assignment
Adjust a now-redundant assignment to extended_regexp_option to make it
zero if grep.extendedRegexp is not set. This is always called right
after init_grep_defaults() which memsets the entire structure to 0, so
there's no need to set it again to zero.

However the reason for the if/else pattern is a holdover from[1] where
this was adjusted from a bitfield assignment to a boolean. Rather than
getting rid of the assignment to 0 in all cases, let's just use the
value returned by git_config_bool(), which is more idiomatic and in
sync with the rest of the boolean handling in this function.

This is a logical follow-up to my commit to remove redundant regflags
assignments[2]. This logic was originally introduced in [3], but as
explained in the former commit it's working around a pattern in our
code that no longer exists, and is now confusing as it leads the
reader to think that this needs to be flipped back & forth.

1. 84befcd0a4 ("grep: add a grep.patternType configuration setting",
   2012-08-03)
2. e0b9f8ae09 ("grep: remove redundant regflags assignments",
   2017-05-25)
3. b22520a37c ("grep: allow -E and -n to be turned on by default via
   configuration", 2011-03-30)

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
Ævar Arnfjörð Bjarmason
e62ba43244 grep: remove redundant double assignment to 0
Stop assigning 0 to the extended_regexp_option field right after we've
zeroed out the entire struct with memset() just a few lines earlier.

Unlike some of the code being refactored in subsequent commits, this
was always completely redundant. See the original code introduced in
84befcd0a4 ("grep: add a grep.patternType configuration setting",
2012-08-03).

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
50f03c6676 Merge branch 'ab/free-and-null'
A common pattern to free a piece of memory and assign NULL to the
pointer that used to point at it has been replaced with a new
FREE_AND_NULL() macro.

* ab/free-and-null:
  *.[ch] refactoring: make use of the FREE_AND_NULL() macro
  coccinelle: make use of the "expression" FREE_AND_NULL() rule
  coccinelle: add a rule to make "expression" code use FREE_AND_NULL()
  coccinelle: make use of the "type" FREE_AND_NULL() rule
  coccinelle: add a rule to make "type" code use FREE_AND_NULL()
  git-compat-util: add a FREE_AND_NULL() wrapper around free(ptr); ptr = NULL
2017-06-24 14:28:41 -07:00
Junio C Hamano
f31d23a399 Merge branch 'bw/config-h'
Fix configuration codepath to pay proper attention to commondir
that is used in multi-worktree situation, and isolate config API
into its own header file.

* bw/config-h:
  config: don't implicitly use gitdir or commondir
  config: respect commondir
  setup: teach discover_git_directory to respect the commondir
  config: don't include config.h by default
  config: remove git_config_iter
  config: create config.h
2017-06-24 14:28:41 -07:00
Junio C Hamano
2f4af84578 Merge branch 'ab/pcre-v2'
Hotfix for a topic already in 'master'.

* ab/pcre-v2:
  grep: fix erroneously copy/pasted variable in check/assert pattern
2017-06-24 14:28:36 -07:00
Ævar Arnfjörð Bjarmason
674ad936bb grep: fix erroneously copy/pasted variable in check/assert pattern
Fix an erroneously copy/pasted check for the pcre2_jit_stack variable
to check pcre2_match_context instead. The former was already checked
in the preceding "if" statement.

This is a trivial and obvious error introduced in my commit
94da9193a6 ("grep: add support for PCRE v2", 2017-06-01).

In practice if pcre2_match_context_create() returned NULL we were
likely in a situation where malloc() was returning NULL, and were thus
screwed anyway, but if only the pcre2_match_context_create() call
returned NULL (through some transitory bug) PCRE v2 would just
allocate and supply its own context object when matching, and we'd run
normally at the trivial expense of not getting a slight speedup by
sharing the context object between successive matches.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-21 09:18:44 -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
Ævar Arnfjörð Bjarmason
88ce3ef636 *.[ch] refactoring: make use of the FREE_AND_NULL() macro
Replace occurrences of `free(ptr); ptr = NULL` which weren't caught by
the coccinelle rule. These fall into two categories:

 - free/NULL assignments one after the other which coccinelle all put
   on one line, which is functionally equivalent code, but very ugly.

 - manually spotted occurrences where the NULL assignment isn't right
   after the free() call.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-16 12:44:09 -07:00
Ævar Arnfjörð Bjarmason
6a83d90207 coccinelle: make use of the "type" FREE_AND_NULL() rule
Apply the result of the just-added coccinelle rule. This manually
excludes a few occurrences, mostly things that resulted in many
FREE_AND_NULL() on one line, that'll be manually fixed in a subsequent
change.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-16 12:44:03 -07:00
Brandon Williams
b2141fc1d2 config: don't include config.h by default
Stop including config.h by default in cache.h.  Instead only include
config.h in those files which require use of the config system.

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-15 12:56:22 -07:00
Brandon Williams
f9704c2d82 diff: convert fill_filespec to struct object_id
Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-02 09:36:07 +09:00
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
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
543f1c0cb0 grep: move is_fixed() earlier to avoid forward declaration
Move the is_fixed() function which are currently only used in
compile_regexp() earlier so it can be used in the PCRE family of
functions in a later 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
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
Ævar Arnfjörð Bjarmason
219e65b65c grep: factor test for \0 in grep patterns into a function
Factor the test for \0 in grep patterns into a function. Since commit
9eceddeec6 ("Use kwset in grep", 2011-08-21) any pattern containing a
\0 is considered fixed as regcomp() can't handle it.

This change makes later changes that make use of either has_null() or
is_fixed() (but not both) smaller.

While I'm at it make the comment conform to the style guide, i.e. add
an opening "/*\n".

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
e0b9f8ae09 grep: remove redundant regflags assignments
Remove redundant assignments to the "regflags" variable. This variable
is only used set under GREP_PATTERN_TYPE_ERE, so there's no need to
un-set it under GREP_PATTERN_TYPE_{FIXED,BRE,PCRE}.

Back in 5010cb5fcc[1], we did do "opt.regflags &= ~REG_EXTENDED" upon
seeing "-G" on the command line and flipped the bit on upon seeing
"-E", but I think that was perfectly sensible and it would have been a
bug if we didn't.  They were part of the command line parsing that
could have seen "-E" on the command line earlier.

When cca2c172 ("git-grep: do not die upon -F/-P when
grep.extendedRegexp is set.", 2011-05-09) switched the command line
parsing to "read into a 'tentatively this is what we saw the last'
variable and then finally commit just once", we didn't touch
opt.regflags for PCRE and FIXED, but we still had to flip regflags
between BRE and ERE, because parsing of grep.extendedregexp
configuration variable directly touched opt.regflags back then, which
was done by b22520a3 ("grep: allow -E and -n to be turned on by
default via configuration", 2011-03-30).

When 84befcd0 ("grep: add a grep.patternType configuration setting",
2012-08-03) introduced extended_regexp_option field, we stopped
flipping regflags while reading the configuration, and that was when
we should have noticed and stopped dropping REG_EXTENDED bit in the
"now we can commit what type to use" helper function.

There is no reason to do this anymore, so stop doing it, more to
reduce "wait this is used under fixed/BRE/PCRE how?" confusion when
reading the code, than to to save ourselves trivial CPU cycles by
removing one assignment.

1. "built-in "git grep"", 2006-04-30.

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
Jeff King
1a168e5c86 convert unchecked snprintf into xsnprintf
These calls to snprintf should always succeed, because their
input is small and fixed. Let's use xsnprintf to make sure
this is the case (and to make auditing for actual truncation
easier).

These could be candidates for turning into heap buffers, but
they fall into a few broad categories that make it not worth
doing:

  - formatting single numbers is simple enough that we can
    see the result should fit

  - the size of a sha1 is likewise well-known, and I didn't
    want to cause unnecessary conflicts with the ongoing
    process to convert these constants to GIT_MAX_HEXSZ

  - the interface for curl_errorstr is dictated by curl

Signed-off-by: Jeff King <peff@peff.net>
2017-03-30 14:59:50 -07:00
Brandon Williams
379642bcd8 grep: set default output method
Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-03-17 12:18:41 -07:00
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
6a67695268 Merge branch 'js/regexec-buf'
Some codepaths in "git diff" used regexec(3) on a buffer that was
mmap(2)ed, which may not have a terminating NUL, leading to a read
beyond the end of the mapped region.  This was fixed by introducing
a regexec_buf() helper that takes a <ptr,len> pair with REG_STARTEND
extension.

* js/regexec-buf:
  regex: use regexec_buf()
  regex: add regexec_buf() that can work on a non NUL-terminated string
  regex: -G<pattern> feeds a non NUL-terminated string to regexec() and fails
2016-09-26 16:09:19 -07:00
Johannes Schindelin
b7d36ffca0 regex: use regexec_buf()
The new regexec_buf() function operates on buffers with an explicitly
specified length, rather than NUL-terminated strings.

We need to use this function whenever the buffer we want to pass to
regexec(3) may have been mmap(2)ed (and is hence not NUL-terminated).

Note: the original motivation for this patch was to fix a bug where
`git diff -G <regex>` would crash. This patch converts more callers,
though, some of which allocated to construct NUL-terminated strings,
or worse, modified buffers to temporarily insert NULs while calling
regexec(3).  By converting them to use regexec_buf(), the code has
become much cleaner.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-21 13:56:15 -07:00
Junio C Hamano
1a5f1a3f25 Merge branch 'js/am-3-merge-recursive-direct'
"git am -3" calls "git merge-recursive" when it needs to fall back
to a three-way merge; this call has been turned into an internal
subroutine call instead of spawning a separate subprocess.

* js/am-3-merge-recursive-direct:
  merge-recursive: flush output buffer even when erroring out
  merge_trees(): ensure that the callers release output buffer
  merge-recursive: offer an option to retain the output in 'obuf'
  merge-recursive: write the commit title in one go
  merge-recursive: flush output buffer before printing error messages
  am -3: use merge_recursive() directly again
  merge-recursive: switch to returning errors instead of dying
  merge-recursive: handle return values indicating errors
  merge-recursive: allow write_tree_from_memory() to error out
  merge-recursive: avoid returning a wholesale struct
  merge_recursive: abort properly upon errors
  prepare the builtins for a libified merge_recursive()
  merge-recursive: clarify code in was_tracked()
  die(_("BUG")): avoid translating bug messages
  die("bug"): report bugs consistently
  t5520: verify that `pull --rebase` shows the helpful advice when failing
2016-08-10 12:33:20 -07:00
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
Johannes Schindelin
ef1177d18e die("bug"): report bugs consistently
The vast majority of error messages in Git's source code which report a
bug use the convention to prefix the message with "BUG:".

As part of cleaning up merge-recursive to stop die()ing except in case of
detected bugs, let's just make the remainder of the bug reports consistent
with the de facto rule.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-07-26 11:13:44 -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
Junio C Hamano
a883c31af6 Merge branch 'nd/icase'
"git grep -i" has been taught to fold case in non-ascii locales
correctly.

* nd/icase:
  grep.c: reuse "icase" variable
  diffcore-pickaxe: support case insensitive match on non-ascii
  diffcore-pickaxe: Add regcomp_or_die()
  grep/pcre: support utf-8
  gettext: add is_utf8_locale()
  grep/pcre: prepare locale-dependent tables for icase matching
  grep: rewrite an if/else condition to avoid duplicate expression
  grep/icase: avoid kwsset when -F is specified
  grep/icase: avoid kwsset on literal non-ascii strings
  test-regex: expose full regcomp() to the command line
  test-regex: isolate the bug test code
  grep: break down an "if" stmt in preparation for next changes
2016-07-19 13:22:17 -07:00
Nguyễn Thái Ngọc Duy
695f95ba5d grep.c: reuse "icase" variable
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
Nguyễn Thái Ngọc Duy
18547aacf5 grep/pcre: support utf-8
In the previous change in this function, we add locale support for
single-byte encodings only. It looks like pcre only supports utf-* as
multibyte encodings, the others are left in the cold (which is
fine).

We need to enable PCRE_UTF8 so pcre can find character boundary
correctly. It's needed for case folding (when --ignore-case is used)
or '*', '+' or similar syntax is used.

The "has_non_ascii()" check is to be on the conservative side. If
there's non-ascii in the pattern, the searched content could still be
in utf-8, but we can treat it just like a byte stream and everything
should work. If we force utf-8 based on locale only and pcre validates
utf-8 and the file content is in non-utf8 encoding, things break.

Noticed-by: Plamen Totev <plamen.totev@abv.bg>
Helped-by: Plamen Totev <plamen.totev@abv.bg>
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
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
Nguyễn Thái Ngọc Duy
e944d9d932 grep: rewrite an if/else condition to avoid duplicate expression
"!icase || ascii_only" is repeated twice in this if/else chain as this
series evolves. Rewrite it (and basically revert the first if
condition back to before the "grep: break down an "if" stmt..." commit).

Helped-by: Junio C Hamano <gitster@pobox.com>
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
Nguyễn Thái Ngọc Duy
793dc676e0 grep/icase: avoid kwsset when -F is specified
Similar to the previous commit, we can't use kws on icase search
outside ascii range. But we can't simply pass the pattern to
regcomp/pcre like the previous commit because it may contain regex
special characters, so we need to quote the regex first.

To avoid misquote traps that could lead to undefined behavior, we
always stick to basic regex engine in this case. We don't need fancy
features for grepping a literal string anyway.

basic_regex_quote_buf() assumes that if the pattern is in a multibyte
encoding, ascii chars must be unambiguously encoded as single
bytes. This is true at least for UTF-8. For others, let's wait until
people yell up. Chances are nobody uses multibyte, non utf-8 charsets
anymore.

Noticed-by: Plamen Totev <plamen.totev@abv.bg>
Helped-by: René Scharfe <l.s.r@web.de>
Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-07-01 12:44:30 -07:00
Nguyễn Thái Ngọc Duy
5c1ebcca4d grep/icase: avoid kwsset on literal non-ascii strings
When we detect the pattern is just a literal string, we avoid heavy
regex engine and use fast substring search implemented in kwsset.c.
But kws uses git-ctype which is locale-independent so it does not know
how to fold case properly outside ascii range. Let regcomp or pcre
take care of this case instead. Slower, but accurate.

Noticed-by: Plamen Totev <plamen.totev@abv.bg>
Helped-by: René Scharfe <l.s.r@web.de>
Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-06-27 07:31:35 -07:00
Nguyễn Thái Ngọc Duy
60452a30f5 grep: break down an "if" stmt in preparation for next changes
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-06-27 07:31:35 -07:00
Junio C Hamano
d15c05a5d0 Merge branch 'rs/xdiff-hunk-with-func-line'
"git show -W" (extend hunks to cover the entire function, delimited
by lines that match the "funcname" pattern) used to show the entire
file when a change added an entire function at the end of the file,
which has been fixed.

* rs/xdiff-hunk-with-func-line:
  xdiff: fix merging of appended hunk with -W
  grep: -W: don't extend context to trailing empty lines
  t7810: add test for grep -W and trailing empty context lines
  xdiff: don't trim common tail with -W
  xdiff: -W: don't include common trailing empty lines in context
  xdiff: ignore empty lines before added functions with -W
  xdiff: handle appended chunks better with -W
  xdiff: factor out match_func_rec()
  t4051: rewrite, add more tests
2016-06-20 11:01:04 -07:00
René Scharfe
4aa2c4753d grep: -W: don't extend context to trailing empty lines
Empty lines between functions are shown by grep -W, as it considers them
to be part of the function preceding them.  They are not interesting in
most languages.  The previous patches stopped showing them for diff -W.

Stop showing empty lines trailing a function with grep -W.  Grep scans
the lines of a buffer from top to bottom and prints matching lines
immediately.  Thus we need to peek ahead in order to determine if an
empty line is part of a function body and worth showing or not.

Remember how far ahead we peeked in order to avoid having to do so
repeatedly when handling multiple consecutive empty lines.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-05-31 13:08:56 -07:00
Nguyễn Thái Ngọc Duy
7645d8f119 grep.c: use error_errno()
While at there, improve the error message a bit (what operation failed?)

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-05-09 12:29:08 -07:00
Jeff King
3733e69464 use xmallocz to avoid size arithmetic
We frequently allocate strings as xmalloc(len + 1), where
the extra 1 is for the NUL terminator. This can be done more
simply with xmallocz, which also checks for integer
overflow.

There's no case where switching xmalloc(n+1) to xmallocz(n)
is wrong; the result is the same length, and malloc made no
guarantees about what was in the buffer anyway. But in some
cases, we can stop manually placing NUL at the end of the
allocated buffer. But that's only safe if it's clear that
the contents will always fill the buffer.

In each case where this patch does so, I manually examined
the control flow, and I tried to err on the side of caution.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-22 14:51:09 -08:00
Jeff King
7ce4fb948c color: add color_set helper for copying raw colors
To set up default colors, we sometimes strcpy() from the
default string literals into our color buffers. This isn't a
bug (assuming the destination is COLOR_MAXLEN bytes), but
makes it harder to audit the code for problematic strcpy
calls.

Let's introduce a color_set which copies under the
assumption that there are COLOR_MAXLEN bytes in the
destination (of course you can call it on a smaller buffer,
so this isn't providing a huge amount of safety, but it's
more convenient than calling xsnprintf yourself).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-10-05 11:08:05 -07:00
Jeff King
19bdd3e7e1 grep: use xsnprintf to format failure message
This looks at first glance like the sprintf can overflow our
buffer, but it's actually fine; the p->origin string is
something constant and small, like "command line" or "-e
option".

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-09-25 10:18:18 -07:00
Junio C Hamano
092c4be7f5 Merge branch 'jk/blame-commit-label'
"git blame HEAD -- missing" failed to correctly say "HEAD" when it
tried to say "No such path 'missing' in HEAD".

* jk/blame-commit-label:
  blame.c: fix garbled error message
  use xstrdup_or_null to replace ternary conditionals
  builtin/commit.c: use xstrdup_or_null instead of envdup
  builtin/apply.c: use xstrdup_or_null instead of null_strdup
  git-compat-util: add xstrdup_or_null helper
2015-02-11 13:39:50 -08:00
Jeff King
8c53f0719b use xstrdup_or_null to replace ternary conditionals
This replaces "x ? xstrdup(x) : NULL" with xstrdup_or_null(x).
The change is fairly mechanical, with the exception of
resolve_refdup, which can eliminate a temporary variable.

There are still a few hits grepping for "?.*xstrdup", but
these are of slightly different forms and cannot be
converted (e.g., "x ? xstrdup(x->foo) : NULL").

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-01-13 10:05:48 -08:00
Junio C Hamano
bf1f639ea2 Merge branch 'rs/grep-color-words'
Allow painting or not painting (partial) matches in context lines
when showing "grep -C<num>" output in color.

* rs/grep-color-words:
  grep: add color.grep.matchcontext and color.grep.matchselected
2014-10-31 11:49:47 -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
f6c5a2968c color_parse: do not mention variable name in error message
Originally the color-parsing function was used only for
config variables. It made sense to pass the variable name so
that the die() message could be something like:

  $ git -c color.branch.plain=bogus branch
  fatal: bad color value 'bogus' for variable 'color.branch.plain'

These days we call it in other contexts, and the resulting
error messages are a little confusing:

  $ git log --pretty='%C(bogus)'
  fatal: bad color value 'bogus' for variable '--pretty format'

  $ git config --get-color foo.bar bogus
  fatal: bad color value 'bogus' for variable 'command line'

This patch teaches color_parse to complain only about the
value, and then return an error code. Config callers can
then propagate that up to the config parser, which mentions
the variable name. Other callers can provide a custom
message. After this patch these three cases now look like:

  $ git -c color.branch.plain=bogus branch
  error: invalid color value: bogus
  fatal: unable to parse 'color.branch.plain' from command-line config

  $ git log --pretty='%C(bogus)'
  error: invalid color value: bogus
  fatal: unable to parse --pretty format

  $ git config --get-color foo.bar bogus
  error: invalid color value: bogus
  fatal: unable to parse default color value

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-14 11:01:21 -07:00
Junio C Hamano
52df9173fa Merge branch 'as/grep-fullname-config'
Add a configuration variable to force --full-name to be default for
"git grep".

This may cause regressions on scripted users that do not expect
this new behaviour.

* as/grep-fullname-config:
  grep: add grep.fullName config variable
2014-06-03 12:06:39 -07:00
Andreas Schwab
6453f7b348 grep: add grep.fullName config variable
This configuration variable sets the default for the --full-name option.

Signed-off-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-03-20 12:38:00 -07:00
Junio C Hamano
6f6be80ef1 Merge branch 'rs/grep-h-c'
"git grep" learns to handle combination of "-h (no header)" and "-c
(counts)".

* rs/grep-h-c:
  grep: support -h (no header) with --count
  t7810: add missing variables to tests in loop
2014-03-18 13:51:20 -07:00
René Scharfe
f76d947ae1 grep: support -h (no header) with --count
Suppress printing the header (filename) with -h even if in -c/--count
mode.  GNU grep and OpenBSD's grep do the same.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-03-11 15:05:28 -07:00
Sun He
50546b15ed Use hashcpy() when copying object names
We invented hashcpy() to keep the abstraction of "object name"
behind it.  Use it instead of calling memcpy() with hard-coded
20-byte length when moving object names between pieces of memory.

Leave ppc/sha1.c as-is, because the function is about the SHA-1 hash
algorithm whose output is and will always be 20 bytes.

Helped-by: Michael Haggerty <mhagger@alum.mit.edu>
Helped-by: Duy Nguyen <pclouds@gmail.com>
Signed-off-by: Sun He <sunheehnus@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-03-06 14:03:12 -08:00
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
918d4e1c90 revisions: initialize revs->grep_filter using grep_init()
Instead of using the hand-rolled initialization sequence,
use grep_init() to populate the necessary bits.  This opens
the door to allow the calling commands to optionally read
grep.* configuration variables via git_config() if they
want to.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-10-09 23:21:29 -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
3083301ead grep.c: make two symbols really file-scope static this time
Adding a declaration at the beginning is not sufficient for obvious
reasons. The definition has to be made static.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-09-20 14:20:09 -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
13e4fc7e01 log --grep/--author: honor --all-match honored for multiple --grep patterns
When we have both header expression (which has to be an OR node by
construction) and a pattern expression (which could be anything), we
create a new top-level OR node to bind them together, and the
resulting expression structure looks like this:

             OR
        /          \
       /            \
   pattern            OR
     / \           /     \
    .....    committer    OR
                         /   \
                     author   TRUE

The three elements on the top-level backbone that are inspected by
the "all-match" logic are "pattern", "committer" and "author".  When
there are more than one elements in the "pattern", the top-level
node of the "pattern" part of the subtree is an OR, and that node is
inspected by "all-match".

The result ends up ignoring the "--all-match" given from the command
line.  A match on either side of the pattern is considered a match,
hence:

        git log --grep=A --grep=B --author=C --all-match

shows the same "authored by C and has either A or B" that is correct
only when run without "--all-match".

Fix this by turning the resulting expression around when "--all-match"
is in effect, like this:

              OR
          /        \
         /          \
        /              OR
    committer        /    \
                 author    \
                           pattern

The set of nodes on the top-level backbone in the resulting
expression becomes "committer", "author", and the nodes that are on
the top-level backbone of the "pattern" subexpression.  This makes
the "all-match" logic inspect the same nodes in "pattern" as the
case without the author and/or the committer restriction, and makes
the earlier "log" example to show "authored by C and has A and has
B", which is what the command line expects.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-09-14 10:12:56 -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
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
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
René Scharfe
2b3873ff34 grep: factor out do_append_grep_pat()
Add do_append_grep_pat() as a shared function for adding patterns to
the header pattern list and the general pattern list.

Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-05-20 15:12:25 -07:00
René Scharfe
fc45675110 grep: factor out create_grep_pat()
Add create_grep_pat(), a shared helper for all grep pattern allocation
and initialization needs.

Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-05-20 15:12:22 -07:00
Junio C Hamano
f5f37461a9 Merge branch 'ah/maint-grep-double-init' into maint
By Angus Hammond
* ah/maint-grep-double-init:
  grep.c: remove redundant line of code
2012-05-11 11:16:09 -07:00
Angus Hammond
2385f24625 grep.c: remove redundant line of code
Signed-off-by: Angus Hammond <angusgh@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-05-07 11:25:04 -07:00
Junio C Hamano
1e4d0875ac Merge branch 'jc/pickaxe-ignore-case'
By Junio C Hamano (2) and Ramsay Jones (1)
* jc/pickaxe-ignore-case:
  ctype.c: Fix a sparse warning
  pickaxe: allow -i to search in patch case-insensitively
  grep: use static trans-case table
2012-03-07 12:12:59 -08:00
Junio C Hamano
0f871cf56e grep: use static trans-case table
In order to prepare the kwset machinery for a case-insensitive search, we
used to use a static table of 256 elements and filled it every time before
calling kwsalloc().  Because the kwset machinery will never modify this
table, just allocate a single instance globally and fill it at the compile
time.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-02-28 14:29:37 -08:00
Junio C Hamano
4d06691eec Sync with 1.7.8.5 2012-02-26 16:42:35 -08:00
Michał Kiedrowicz
fba4f1259d grep -P: Fix matching ^ and $
When "git grep" is run with -P/--perl-regexp, it doesn't match ^ and $ at
the beginning/end of the line.  This is because PCRE normally matches ^
and $ at the beginning/end of the whole text, not for each line, and "git
grep" passes a large chunk of text (possibly containing many lines) to
pcre_exec() and then splits the text into lines.

This makes "git grep -P" behave differently from "git grep -E" and also
from "grep -P" and "pcregrep":

	$ cat file
	a
	 b
	$ git grep --no-index -P '^ ' file
	$ git grep --no-index -E '^ ' file
	file: b
	$ grep -c -P '^ ' file
	 b
	$ pcregrep -c '^ ' file
	 b

Reported-by: Zbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl>
Signed-off-by: Michał Kiedrowicz <michal.kiedrowicz@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-02-26 16:34:03 -08:00
Jeff King
08265798e1 grep: load file data after checking binary-ness
Usually we load each file to grep into memory, check whether
it's binary, and then either grep it (the default) or not
(if "-I" was given).

In the "-I" case, we can skip loading the file entirely if
it is marked as binary via gitattributes. On my giant
3-gigabyte media repository, doing "git grep -I foo" went
from:

  real    0m0.712s
  user    0m0.044s
  sys     0m4.780s

to:

  real    0m0.026s
  user    0m0.016s
  sys     0m0.020s

Obviously this is an extreme example. The repo is almost
entirely binary files, and you can see that we spent all of
our time asking the kernel to read() the data. However, with
a cold disk cache, even avoiding a few binary files can have
an impact.

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
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
Jeff King
b3aeb285d0 grep: move sha1-reading mutex into low-level code
The multi-threaded git-grep code needs to serialize access
to the thread-unsafe read_sha1_file call. It does this with
a mutex that is local to builtin/grep.c.

Let's instead push this down into grep.c, where it can be
used by both builtin/grep.c and grep.c. This will let us
safely teach the low-level grep.c code tricks that involve
reading from the object db.

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
Jeff King
78db6ea9dc 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 10:36:07 -08:00