Commit Graph

115 Commits

Author SHA1 Message Date
Ævar Arnfjörð Bjarmason
dfd0a89374 cocci & cache.h: remove "USE_THE_INDEX_COMPATIBILITY_MACROS"
Have the last users of "USE_THE_INDEX_COMPATIBILITY_MACROS" use the
underlying *_index() variants instead. Now all previous users of
"USE_THE_INDEX_COMPATIBILITY_MACROS" have been migrated away from the
wrapper macros, and if applicable to use the "USE_THE_INDEX_VARIABLE"
added in [1].

Let's leave the "index-compatibility.cocci" in place, even though it
won't be doing anything on "master". It will benefit any out-of-tree
code that need to use these compatibility macros. We can eventually
remove it.

1. bdafeae0b9 (cache.h & test-tool.h: add & use
   "USE_THE_INDEX_VARIABLE", 2022-11-19)

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-02-10 11:38:40 -08:00
Ævar Arnfjörð Bjarmason
fcb864bce7 cache-tree API: remove redundant update_main_cache_tree()
Remove the redundant update_main_cache_tree() function, and make its
users use cache_tree_update() instead.

The behavior of populating the "the_index.cache_tree" if it wasn't
present already was needed when this function was introduced in [1],
but it hasn't been needed since [2]; The "cache_tree_update()" will
now lazy-allocate, so there's no need for the wrapper.

1. 996277c520 (Refactor cache_tree_update idiom from commit,
   2011-12-06)
2. fb0882648e (cache-tree: clean up cache_tree_update(), 2021-01-23)

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-02-10 11:38:14 -08:00
Ævar Arnfjörð Bjarmason
99370863e2 cocci & cache-tree.h: migrate "write_cache_as_tree" to "*_index_*"
Add a trivial rule for "write_cache_as_tree" to
"index-compatibility.cocci", and apply it. This was left out of the
rules added in 0e6550a2c6 (cocci: add a
index-compatibility.pending.cocci, 2022-11-19) because this
compatibility wrapper lived in "cache-tree.h", not "cache.h"

But it's like the other "USE_THE_INDEX_COMPATIBILITY_MACROS", so let's
migrate it too.

The replacement of "USE_THE_INDEX_COMPATIBILITY_MACROS" here with
"USE_THE_INDEX_VARIABLE" is a manual change on top, now that these
files only use "&the_index", and don't need any compatibility
macros (or functions).

The wrapping of some argument lists is likewise manual, as coccinelle
would otherwise give us overly long argument lists.

The reason for putting the "O" in the cocci rule on the "-" and "+"
lines is because I couldn't get correct whitespacing otherwise,
i.e. I'd end up with "oid,&the_index", not "oid, &the_index".

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-02-10 11:37:49 -08:00
Ævar Arnfjörð Bjarmason
babed893f5 cocci & cache.h: apply pending "index_cache_pos" rule
Apply the rule added in [1] to change "cache_name_pos" to
"index_name_pos", which allows us to get rid of another
"USE_THE_INDEX_COMPATIBILITY_MACROS" macro.

The replacement of "USE_THE_INDEX_COMPATIBILITY_MACROS" here with
"USE_THE_INDEX_VARIABLE" is a manual change on top, now that these
files only use "&the_index", and don't need any compatibility
macros (or functions).

1. 0e6550a2c6 (cocci: add a index-compatibility.pending.cocci,
   2022-11-19)

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-02-10 11:37:27 -08:00
Ævar Arnfjörð Bjarmason
cec13b9514 cocci & cache.h: fully apply "active_nr" part of index-compatibility
Apply the "active_nr" part of "index-compatibility.pending.cocci",
which was left out in [1] due to an in-flight conflict. As of [2] the
topic we conflicted with has been merged to "master", so we can fully
apply this rule.

1. dc594180d9 (cocci & cache.h: apply variable section of "pending"
   index-compatibility, 2022-11-19)
2. 9ea1378d04 (Merge branch 'ab/various-leak-fixes', 2022-12-14)

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-02-10 11:31:18 -08:00
René Scharfe
6e57841096 use DUP_ARRAY
Add a semantic patch for replace ALLOC_ARRAY+COPY_ARRAY with DUP_ARRAY
to reduce code duplication and apply its results.

Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-01-09 13:28:36 +09:00
Junio C Hamano
805265fcf7 Merge branch 'ab/fewer-the-index-macros'
Squelch warnings from Coccinelle

* ab/fewer-the-index-macros:
  cocci: avoid "should ... be a metavariable" warnings
2022-12-01 18:38:07 +09:00
Ævar Arnfjörð Bjarmason
cddd68ae33 cocci: avoid "should ... be a metavariable" warnings
Since [1] running "make coccicheck" has resulted in [2] being emitted
to the *.log files for the "spatch" run, and in the case of "make
coccicheck-test" we'd emit these to the user's terminal.

Nothing was broken as a result, but let's refactor the relevant rules
to eliminate the ambiguity between a possible variable and an
identifier.

1. 0e6550a2c6 (cocci: add a index-compatibility.pending.cocci,
   2022-11-19)
2. warning: line 257: should active_cache be a metavariable?
   warning: line 260: should active_cache_changed be a metavariable?
   warning: line 263: should active_cache_tree be a metavariable?
   warning: line 271: should active_nr be a metavariable?

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-12-01 07:25:57 +09:00
Junio C Hamano
041df69edd Merge branch 'ab/fewer-the-index-macros'
Progress on removing 'the_index' convenience wrappers.

* ab/fewer-the-index-macros:
  cocci: apply "pending" index-compatibility to some "builtin/*.c"
  cache.h & test-tool.h: add & use "USE_THE_INDEX_VARIABLE"
  {builtin/*,repository}.c: add & use "USE_THE_INDEX_VARIABLE"
  cocci: apply "pending" index-compatibility to "t/helper/*.c"
  cocci & cache.h: apply variable section of "pending" index-compatibility
  cocci & cache.h: apply a selection of "pending" index-compatibility
  cocci: add a index-compatibility.pending.cocci
  read-cache API & users: make discard_index() return void
  cocci & cache.h: remove rarely used "the_index" compat macros
  builtin/{grep,log}.: don't define "USE_THE_INDEX_COMPATIBILITY_MACROS"
  cache.h: remove unused "the_index" compat macros
2022-11-28 12:13:46 +09:00
Ævar Arnfjörð Bjarmason
07047d6829 cocci: apply "pending" index-compatibility to some "builtin/*.c"
Apply "index-compatibility.pending.cocci" rule to "builtin/*", but
exclude those where we conflict with in-flight changes.

As a result some of them end up using only "the_index", so let's have
them use the more narrow "USE_THE_INDEX_VARIABLE" rather than
"USE_THE_INDEX_COMPATIBILITY_MACROS".

Manual changes not made by coccinelle, that were squashed in:

* Whitespace-wrap argument lists for repo_hold_locked_index(),
  repo_read_index_preload() and repo_refresh_and_write_index(), in cases
  where the line became too long after the transformation.
* Change "refresh_cache()" to "refresh_index()" in a comment in
  "builtin/update-index.c".
* For those whose call was followed by perror("<macro-name>"), change
  it to perror("<function-name>"), referring to the new function.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-11-21 12:06:15 +09:00
Ævar Arnfjörð Bjarmason
dc594180d9 cocci & cache.h: apply variable section of "pending" index-compatibility
Mostly apply the part of "index-compatibility.pending.cocci" that
renames the global variables like "active_nr", which are a shorthand
to referencing (in that case) a struct member as "the_index.cache_nr".

In doing so move more of "index-compatibility.pending.cocci" to
"index-compatibility.cocci".

In the case of "active_nr" we'd have a textual conflict with
"ab/various-leak-fixes" in "next"[1]. Let's exclude that specific case
while moving the rule over from "pending".

1. 407b94280f8 (commit: discard partial cache before (re-)reading it,
   2022-11-08)

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-11-21 12:06:15 +09:00
Ævar Arnfjörð Bjarmason
031b2033e0 cocci & cache.h: apply a selection of "pending" index-compatibility
Apply a selection of rules in "index-compatibility.pending.cocci"
tree-wide, and in doing so migrate them to
"index-compatibility.cocci".

As in preceding commits the only manual changes here are the macro
removals in "cache.h", and the update to the '*.cocci" rules. The rest
of the C code changes are the result of applying those updated rules.

Move rules for some rarely used cache compatibility macros from
"index-compatibility.pending.cocci" to "index-compatibility.cocci" and
apply them.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-11-21 12:06:15 +09:00
Ævar Arnfjörð Bjarmason
0e6550a2c6 cocci: add a index-compatibility.pending.cocci
Add a coccinelle rule which covers the rest of the macros guarded by
"USE_THE_INDEX_COMPATIBILITY_MACROS" cache.h. If the result of this
were applied it can be reduced down to just:

	#ifdef USE_THE_INDEX_COMPATIBILITY_MACROS
	extern struct index_state the_index;
	#endif

But that patch is just under 2000 lines, so let's first add this as a
"pending", and then incrementally pick changes from it in subsequent
commits. In doing that we'll migrate rules from this
"index-compatibility.pending.cocci" to the "index-compatibility.cocci"
created in a preceding commit.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-11-21 12:06:15 +09:00
Ævar Arnfjörð Bjarmason
fbc1ed629e cocci & cache.h: remove rarely used "the_index" compat macros
Since 4aab5b46f4 (Make read-cache.c "the_index" free., 2007-04-01)
we've been undergoing a slow migration away from these macros, but
haven't made much progress since f8adbec9fe (cache.h: flip
NO_THE_INDEX_COMPATIBILITY_MACROS switch, 2019-01-24).

Let's move forward a bit by changing the users of those macros that
are rare enough that we can convert them in one go, and then remove
the compatibility shim.

The only manual change to the C code here is to "cache.h", the rest is
all the result of applying the new "index-compatibility.cocci".

Even though it's a one-off, let's keep the coccinelle rules for
now. We'll extend them in subsequent commits, and this will help
anything that's in-flight or out-of-tree to migrate.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-11-21 12:06:15 +09:00
Ævar Arnfjörð Bjarmason
6fae3aaf22 spatchcache: add a ccache-alike for "spatch"
Add a rather trivial "spatchcache", with this running e.g.:

	make cocciclean
	make contrib/coccinelle/free.cocci.patch \
		SPATCH=contrib/coccicheck/spatchcache \
		SPATCH_FLAGS=--very-quiet

Is cut down from ~20s to ~5s on my system. Much of that is either
fixable shell overhead, or the around 40 files we "CANTCACHE" (see the
implementation).

This uses "redis" as a cache by default, but it's configurable. See
the embedded documentation.

This is *not* like ccache in that we won't cache failed spatch
invocations, or those where spatch suggests changes for us. Those
cases are so rare that I didn't think it was worth the bother, by far
the most common case is that it has no suggested changes. We'll also
refuse to cache any "spatch" invocation that has output on stderr,
which means that "--very-quiet" must be added to "SPATCH_FLAGS".

Because we narrow the cache to that we don't need to save away stdout,
stderr & the exit code. We simply cache the cases where we had no
suggested changes.

Another benchmark is to compare this with the previous
SPATCH_BATCH_SIZE=N, as noted in [1]. Before this (on my 8 core system) running:

	make clean; time make contrib/coccinelle/array.cocci.patch SPATCH_BATCH_SIZE=0

Would take 33s, but with the preceding changes running without this
"spatchcache" is slightly slower, or around 35s:

	make clean; time make contrib/coccinelle/array.cocci.patch

Now doing the same with SPATCH=contrib/coccinelle/spatchcache will
take around 6s, but we'll need to compile the *.o files first to take
full advantage of it (which can be fast with "ccache"):

	make clean; make; time make contrib/coccinelle/array.cocci.patch SPATCH=contrib/coccinelle/spatchcache

1. https://lore.kernel.org/git/YwdRqP1CyUAzCEn2@coredump.intra.peff.net/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-02 21:22:16 -04:00
Ævar Arnfjörð Bjarmason
d0e624aed7 cocci: run against a generated ALL.cocci
The preceding commits to make the "coccicheck" target incremental made
it slower in some cases. As an optimization let's not have the
many=many mapping of <*.cocci>=<*.[ch]>, but instead concat the
<*.cocci> into an ALL.cocci, and then run one-to-many
ALL.cocci=<*.[ch]>.

A "make coccicheck" is now around 2x as fast as it was on "master",
and around 1.5x as fast as the preceding change to make the run
incremental:

	$ git hyperfine -L rev origin/master,HEAD~,HEAD -p 'make clean' 'make coccicheck SPATCH=spatch COCCI_SOURCES="$(echo $(ls o*.c builtin/h*.c))"' -r 3
	Benchmark 1: make coccicheck SPATCH=spatch COCCI_SOURCES="$(echo $(ls o*.c builtin/h*.c))"' in 'origin/master
	  Time (mean ± σ):      4.258 s ±  0.015 s    [User: 27.432 s, System: 1.532 s]
	  Range (min … max):    4.241 s …  4.268 s    3 runs

	Benchmark 2: make coccicheck SPATCH=spatch COCCI_SOURCES="$(echo $(ls o*.c builtin/h*.c))"' in 'HEAD~
	  Time (mean ± σ):      5.365 s ±  0.079 s    [User: 36.899 s, System: 1.810 s]
	  Range (min … max):    5.281 s …  5.436 s    3 runs

	Benchmark 3: make coccicheck SPATCH=spatch COCCI_SOURCES="$(echo $(ls o*.c builtin/h*.c))"' in 'HEAD
	  Time (mean ± σ):      2.725 s ±  0.063 s    [User: 14.796 s, System: 0.233 s]
	  Range (min … max):    2.667 s …  2.792 s    3 runs

	Summary
	  'make coccicheck SPATCH=spatch COCCI_SOURCES="$(echo $(ls o*.c builtin/h*.c))"' in 'HEAD' ran
	    1.56 ± 0.04 times faster than 'make coccicheck SPATCH=spatch COCCI_SOURCES="$(echo $(ls o*.c builtin/h*.c))"' in 'origin/master'
	    1.97 ± 0.05 times faster than 'make coccicheck SPATCH=spatch COCCI_SOURCES="$(echo $(ls o*.c builtin/h*.c))"' in 'HEAD~'

This can be turned off with SPATCH_CONCAT_COCCI, but as the
beneficiaries of "SPATCH_CONCAT_COCCI=" would mainly be those
developing the *.cocci rules themselves, let's leave this optimization
on by default.

For more information see my "Optimizing *.cocci rules by concat'ing
them" (<220901.8635dbjfko.gmgdl@evledraar.gmail.com>) on the
cocci@inria.fr mailing list.

This potentially changes the results of our *.cocci rules, but as
noted in that discussion it should be safe for our use. We don't name
rules, or if we do their names don't conflict across our *.cocci
files.

To the extent that we'd have any inter-dependencies between rules this
doesn't make that worse, as we'd have them now if we ran "make
coccicheck", applied the results, and would then have (due to
hypothetical interdependencies) suggested changes on the subsequent
"make coccicheck".

Our "coccicheck-test" target makes use of the ALL.cocci when running
tests, e.g. when testing unused.{c,out} we test it against ALL.cocci,
not unused.cocci. We thus assert (to the extent that we have test
coverage) that this concatenation doesn't change the expected results
of running these rules.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-02 21:22:16 -04:00
Ævar Arnfjörð Bjarmason
340a4cb25c cocci rules: remove <id>'s from rules that don't need them
The <id> in the <rulename> part of the coccinelle syntax[1] is for our
purposes there to declares if we have inter-dependencies between
different rules.

But such <id>'s must be unique within a given semantic patch file.  As
we'll be processing a concatenated version of our rules in the
subsequent commit let's remove these names. They weren't being used
for the semantic patches themselves, and equated to a short comment
about the rule.

Both the filename and context of the rules makes it clear what they're
doing, so we're not gaining anything from keeping these. Retaining
them goes against recommendations that "contrib/coccinelle/README"
will be making in the subsequent commit.

This leaves only one named rule in our sources, where it's needed for
a "<id> <-> <extends> <id>" relationship:

	$ git -P grep '^@ ' -- contrib/coccinelle/
	contrib/coccinelle/swap.cocci:@ swap @
	contrib/coccinelle/swap.cocci:@ extends swap @

1. https://coccinelle.gitlabpages.inria.fr/website/docs/main_grammar.html

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-02 21:22:16 -04:00
Ævar Arnfjörð Bjarmason
316e3886e3 cocci: optimistically use COMPUTE_HEADER_DEPENDENCIES
Improve the incremental rebuilding support of "coccicheck" by
piggy-backing on the computed dependency information of the
corresponding *.o file, rather than rebuilding all <RULE>/<FILE> pairs
if either their corresponding file changes, or if any header changes.

This in effect uses the same method that the "sparse" target was made
to use in c234e8a0ec (Makefile: make the "sparse" target non-.PHONY,
2021-09-23), except that the dependency on the *.o file isn't a hard
one, we check with $(wildcard) if the *.o file exists, and if so we'll
depend on it.

This means that the common case of:

	make
	make coccicheck

Will benefit from incremental rebuilding, now changing e.g. a header
will only re-run "spatch" on those those *.c files that make use of
it:

By depending on the *.o we piggy-back on
COMPUTE_HEADER_DEPENDENCIES. See c234e8a0ec (Makefile: make the
"sparse" target non-.PHONY, 2021-09-23) for prior art of doing that
for the *.sp files. E.g.:

    make contrib/coccinelle/free.cocci.patch
    make -W column.h contrib/coccinelle/free.cocci.patch

Will take around 15 seconds for the second command on my 8 core box if
I didn't run "make" beforehand to create the *.o files. But around 2
seconds if I did and we have those "*.o" files.

Notes about the approach of piggy-backing on *.o for dependencies:

 * It *is* a trade-off since we'll pay the extra cost of running the C
   compiler, but we're probably doing that anyway. The compiler is much
   faster than "spatch", so even though we need to re-compile the *.o to
   create the dependency info for the *.c for "spatch" it's
   faster (especially if using "ccache").

 * There *are* use-cases where some would like to have *.o files
   around, but to have the "make coccicheck" ignore them. See:
   https://lore.kernel.org/git/20220826104312.GJ1735@szeder.dev/

   For those users a:

	make
	make coccicheck SPATCH_USE_O_DEPENDENCIES=

   Will avoid considering the *.o files.

 * If that *.o file doesn't exist we'll depend on an intermediate file
   of ours which in turn depends on $(FOUND_H_SOURCES).

   This covers both an initial build, or where "coccicheck" is run
   without running "all" beforehand, and because we run "coccicheck"
   on e.g. files in compat/* that we don't know how to build unless
   the requisite flag was provided to the Makefile.

   Most of the runtime of "incremental" runs is now spent on various
   compat/* files, i.e. we conditionally add files to COMPAT_OBJS, and
   therefore conflate whether we *can* compile an object and generate
   dependency information for it with whether we'd like to link it
   into our binary.

   Before this change the distinction didn't matter, but now one way
   to make this even faster on incremental builds would be to peel
   those concerns apart so that we can see that e.g. compat/mmap.c
   doesn't depend on column.h.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-02 21:22:16 -04:00
Ævar Arnfjörð Bjarmason
f1c903debd cocci: make "coccicheck" rule incremental
Optimize the very slow "coccicheck" target to take advantage of
incremental rebuilding, and fix outstanding dependency problems with
the existing rule.

The rule is now faster both on the initial run as we can make better
use of GNU make's parallelism than the old ad-hoc combination of
make's parallelism combined with $(SPATCH_BATCH_SIZE) and/or the
"--jobs" argument to "spatch(1)".

It also makes us *much* faster when incrementally building, it's now
viable to "make coccicheck" as topic branches are merged down.

The rule didn't use FORCE (or its equivalents) before, so a:

	make coccicheck
	make coccicheck

Would report nothing to do on the second iteration. But all of our
patch output depended on all $(COCCI_SOURCES) files, therefore e.g.:

    make -W grep.c coccicheck

Would do a full re-run, i.e. a a change in a single file would force
us to do a full re-run.

The reason for this (not the initial rationale, but my analysis) is:

* Since we create a single "*.cocci.patch+" we don't know where to
  pick up where we left off, or how to incrementally merge e.g. a
  "grep.c" change with an existing *.cocci.patch.

* We've been carrying forward the dependency on the *.c files since
  63f0a758a0 (add coccicheck make target, 2016-09-15) the rule was
  initially added as a sort of poor man's dependency discovery.

  As we don't include other *.c files depending on other *.c files
  has always been broken, as could be trivially demonstrated
  e.g. with:

       make coccicheck
       make -W strbuf.h coccicheck

  However, depending on the corresponding *.c files has been doing
  something, namely that *if* an API change modified both *.c and *.h
  files we'd catch the change to the *.h we care about via the *.c
  being changed.

  For API changes that happened only via *.h files we'd do the wrong
  thing before this change, but e.g. for function additions (not
  "static inline" ones) catch the *.h change by proxy.

Now we'll instead:

 * Create a <RULE>/<FILE> pair in the .build directory, E.g. for
   swap.cocci and grep.c we'll create
   .build/contrib/coccinelle/swap.cocci.patch/grep.c.

   That file is the diff we'll apply for that <RULE>-<FILE>
   combination, if there's no changes to me made (the common case)
   it'll be an empty file.

 * Our generated *.patch
   file (e.g. contrib/coccinelle/swap.cocci.patch) is now a simple "cat
   $^" of all of all of the <RULE>/<FILE> files for a given <RULE>.

   In the case discussed above of "grep.c" being changed we'll do the
   full "cat" every time, so they resulting *.cocci.patch will always
   be correct and up-to-date, even if it's "incrementally updated".

   See 1cc0425a27 (Makefile: have "make pot" not "reset --hard",
   2022-05-26) for another recent rule that used that technique.

As before we'll:

 * End up generating a contrib/coccinelle/swap.cocci.patch, if we
   "fail" by creating a non-empty patch we'll still exit with a zero
   exit code.

   Arguably we should move to a more Makefile-native way of doing
   this, i.e. fail early, and if we want all of the "failed" changes
   we can use "make -k", but as the current
   "ci/run-static-analysis.sh" expects us to behave this way let's
   keep the existing behavior of exhaustively discovering all cocci
   changes, and only failing if spatch itself errors out.

Further implementation details & notes:

 * Before this change running "make coccicheck" would by default end
   up pegging just one CPU at the very end for a while, usually as
   we'd finish whichever *.cocci rule was the most expensive.

   This could be mitigated by combining "make -jN" with
   SPATCH_BATCH_SIZE, see 960154b9c1 (coccicheck: optionally batch
   spatch invocations, 2019-05-06).

   There will be cases where getting rid of "SPATCH_BATCH_SIZE" makes
   things worse, but a from-scratch "make coccicheck" with the default
   of SPATCH_BATCH_SIZE=1 (and tweaking it doesn't make a difference)
   is faster (~3m36s v.s. ~3m56s) with this approach, as we can feed
   the CPU more work in a less staggered way.

 * Getting rid of "SPATCH_BATCH_SIZE" particularly helps in cases
   where the default of 1 yields parallelism under "make coccicheck",
   but then running e.g.:

       make -W contrib/coccinelle/swap.cocci coccicheck

   I.e. before that would use only one CPU core, until the user
   remembered to adjust "SPATCH_BATCH_SIZE" differently than the
   setting that makes sense when doing a non-incremental run of "make
   coccicheck".

 * Before the "make coccicheck" rule would have to clean
   "contrib/coccinelle/*.cocci.patch*", since we'd create "*+" and
   "*.log" files there. Now those are created in
   .build/contrib/coccinelle/, which is covered by the "cocciclean" rule
   already.

Outstanding issues & future work:

 * We could get rid of "--all-includes" in favor of manually
   specifying a list of includes to give to "spatch(1)".

   As noted upthread of [1] a naïve removal of "--all-includes" will
   result in broken *.cocci patches, but if we know the exhaustive
   list of includes via COMPUTE_HEADER_DEPENDENCIES we don't need to
   re-scan for them, we could grab the headers to include from the
   .depend.d/<file>.o.d and supply them with the "--include" option to
   spatch(1).q

1. https://lore.kernel.org/git/87ft18tcog.fsf@evledraar.gmail.com/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-02 21:22:16 -04:00
Ævar Arnfjörð Bjarmason
895ae7ae2a cocci rules: remove unused "F" metavariable from pending rule
Fix an issue with a rule added in 9b45f49981 (object-store: prepare
has_{sha1, object}_file to handle any repo, 2018-11-13). We've been
spewing out this warning into our $@.log since that rule was added:

	warning: rule starting on line 21: metavariable F not used in the - or context code

We should do a better job of scouring our coccinelle log files for
such issues, but for now let's fix this as a one-off.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-02 21:22:15 -04:00
Junio C Hamano
2fb377e569 Merge branch 'rs/cocci-array-copy'
A coccinelle rule (in contrib/) to encourage use of COPY_ARRAY
macro has been improved.

* rs/cocci-array-copy:
  cocci: avoid normalization rules for memcpy
2022-07-19 16:40:18 -07:00
René Scharfe
f53156f2ee cocci: avoid normalization rules for memcpy
Some of the rules for using COPY_ARRAY instead of memcpy with sizeof are
intended to reduce the number of sizeof variants to deal with.  They can
have unintended side effects if only they match, but not the one for the
COPY_ARRAY conversion at the end.

Avoid these side effects by instead using a self-contained rule for each
combination of array and pointer for source and destination which lists
all sizeof variants inline.

This lets "make contrib/coccinelle/array.cocci.patch" take 15% longer on
my machine, but gives peace of mind that no incomplete transformation
will be generated.

Suggested-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-10 14:52:05 -07:00
Ævar Arnfjörð Bjarmason
06f5f8940c cocci: generalize "unused" rule to cover more than "strbuf"
Generalize the newly added "unused.cocci" rule to find more than just
"struct strbuf", let's have it find the same unused patterns for
"struct string_list", as well as other code that uses
similar-looking *_{release,clear,free}() and {release,clear,free}_*()
functions.

We're intentionally loose in accepting e.g. a "strbuf_init(&sb)"
followed by a "string_list_clear(&sb, 0)".  It's assumed that the
compiler will catch any such invalid code, i.e. that our
constructors/destructors don't take a "void *".

See [1] for example of code that would be covered by the
"get_worktrees()" part of this rule. We'd still need work that the
series is based on (we were passing "worktrees" to a function), but
could now do the change in [1] automatically.

1. https://lore.kernel.org/git/Yq6eJFUPPTv%2Fzc0o@coredump.intra.peff.net/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-06 12:24:43 -07:00
Ævar Arnfjörð Bjarmason
4f40f6cb73 cocci: add and apply a rule to find "unused" strbufs
Add a coccinelle rule to remove "struct strbuf" initialization
followed by calling "strbuf_release()" function, without any uses of
the strbuf in the same function.

See the tests in contrib/coccinelle/tests/unused.{c,res} for what it's
intended to find and replace.

The inclusion of "contrib/scalar/scalar.c" is because "spatch" was
manually run on it (we don't usually run spatch on contrib).

Per the "buggy code" comment we also match a strbuf_init() before the
xmalloc(), but we're not seeking to be so strict as to make checks
that the compiler will catch for us redundant. Saying we'll match
either "init" or "xmalloc" lines makes the rule simpler.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-06 12:24:43 -07:00
Ævar Arnfjörð Bjarmason
f7ff6597a7 cocci: add a "coccicheck-test" target and test *.cocci rules
Add a "coccicheck-test" target to test our *.cocci rules, and as a
demonstration add tests for the rules added in 39ea59a257 (remove
unnecessary NULL check before free(3), 2016-10-08) and
1b83d1251e (coccinelle: add a rule to make "expression" code use
FREE_AND_NULL(), 2017-06-15).

I considered making use of the "spatch --test" option, and the choice
of a "tests" over a "t" directory is to make these tests compatible
with such a future change.

Unfortunately "spatch --test" doesn't return meaningful exit codes,
AFAICT you need to "grep" its output to see if the *.res is what you
expect. There's "--test-okfailed", but I didn't find a way to sensibly
integrate those (it relies on some in-between status files, but
doesn't help with the status codes).

Instead let's use a "--sp-file" pattern similar to the main
"coccicheck" rule, with the difference that we use and compare the
two *.res files with cmp(1).

The --very-quiet and --no-show-diff options ensure that we don't need
to pipe stdout and stderr somewhere. Unlike the "%.cocci.patch" rule
we're not using the diff.

The "cmp || git diff" is optimistically giving us better output on
failure, but even if we only have POSIX cmp and no system git
installed we'll still fail with the "cmp", just with an error message
that isn't as friendly. The "2>/dev/null" is in case we don't have a
"git" installed.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-06 12:24:43 -07:00
Junio C Hamano
99bbf4739d Merge branch 'jc/cocci-cleanup'
Remove a coccinelle rule that is no longer relevant.

* jc/cocci-cleanup:
  cocci: retire is_null_sha1() rule
2022-06-17 10:33:31 -07:00
Junio C Hamano
b1299de4a1 cocci: retire is_null_sha1() rule
Since 8d4d86b0 (cache: remove null_sha1, 2019-08-18) removed the
is_null_sha1() function, rewrite rules to correct callers of the
function to use is_null_oid() instead has become irrelevant, as any
new callers of the function will get caught by the compiler much
more quickly without spending cycles on Coccinelle.

Remove these rules.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-07 15:53:24 -07:00
Junio C Hamano
2da81d1efb Merge branch 'ab/plug-leak-in-revisions'
Plug the memory leaks from the trickiest API of all, the revision
walker.

* ab/plug-leak-in-revisions: (27 commits)
  revisions API: add a TODO for diff_free(&revs->diffopt)
  revisions API: have release_revisions() release "topo_walk_info"
  revisions API: have release_revisions() release "date_mode"
  revisions API: call diff_free(&revs->pruning) in revisions_release()
  revisions API: release "reflog_info" in release revisions()
  revisions API: clear "boundary_commits" in release_revisions()
  revisions API: have release_revisions() release "prune_data"
  revisions API: have release_revisions() release "grep_filter"
  revisions API: have release_revisions() release "filter"
  revisions API: have release_revisions() release "cmdline"
  revisions API: have release_revisions() release "mailmap"
  revisions API: have release_revisions() release "commits"
  revisions API users: use release_revisions() for "prune_data" users
  revisions API users: use release_revisions() with UNLEAK()
  revisions API users: use release_revisions() in builtin/log.c
  revisions API users: use release_revisions() in http-push.c
  revisions API users: add "goto cleanup" for release_revisions()
  stash: always have the owner of "stash_info" free it
  revisions API users: use release_revisions() needing REV_INFO_INIT
  revision.[ch]: document and move code declared around "init"
  ...
2022-06-07 14:10:56 -07:00
Junio C Hamano
538dc459a0 Merge branch 'ep/maint-equals-null-cocci'
Introduce and apply coccinelle rule to discourage an explicit
comparison between a pointer and NULL, and applies the clean-up to
the maintenance track.

* ep/maint-equals-null-cocci:
  tree-wide: apply equals-null.cocci
  tree-wide: apply equals-null.cocci
  contrib/coccinnelle: add equals-null.cocci
2022-05-20 15:26:59 -07:00
Junio C Hamano
88cbd17e87 Merge branch 'ab/misc-cleanup'
Code clean-up.

* ab/misc-cleanup:
  alloc.[ch]: remove alloc_report() function
  object-store.h: remove unused has_sha1_file*()
  pack-bitmap-write: remove unused bitmap_reset() function
  xdiff/xmacros.h: remove unused XDL_PTRFREE
  configure.ac: remove USE_PIC comment
  run-command.h: remove always unused "clean_on_exit_handler_cbdata"
2022-05-10 17:41:10 -07:00
Elia Pinto
7a618493fa contrib/coccinnelle: add equals-null.cocci
Add a coccinelle semantic patch necessary to reinforce the git coding style
guideline:

"Do not explicitly compute an integral value with constant 0 or '\ 0', or a
pointer value with constant NULL."

Signed-off-by: Elia Pinto <gitter.spiros@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-02 09:47:55 -07:00
Junio C Hamano
08bdd3a185 cocci: drop bogus xstrdup_or_null() rule
13092a91 (cocci: refactor common patterns to use xstrdup_or_null(),
2016-10-12) introduced a rule to rewrite this conditional call to
xstrdup(E) and an assignment to variable V:

    - if (E)
    -    V = xstrdup(E);

into an unconditional call to xstrdup_or_null(E) and an assignment
to variable V:

    + V = xstrdup_or_null(E);

which is utterly bogus.  The original code may already have an
acceptable value in V and the conditional assignment may be to
improve the value already in V with a copy of a better value E when
(and only when) E is not NULL.

The rewritten construct unconditionally discards the existing value
of V and replaces it with a copy of E, even when E is NULL, which
changes the meaning of the program.

By the way, if it were

	-if (E && !V)
	-	V = xstrdup(E);
	+V = xstrdup_or_null(E);

it would probably have been correct.  But there is no existing code
that would have been improved by such a rule, so let's just remove
the bogus one without replacing with the more specific one.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-04-30 22:23:11 -07:00
Ævar Arnfjörð Bjarmason
bf20fe4ca8 cocci: add and apply free_commit_list() rules
Add and apply coccinelle rules to remove "if (E)" before
"free_commit_list(E)", the function can accept NULL, and further
change cases where "E = NULL" followed to also be unconditionally.

The code changes in this commit were entirely made by the coccinelle
rule being added here, and applied with:

    make contrib/coccinelle/free.cocci.patch
    patch -p1 <contrib/coccinelle/free.cocci.patch

The only manual intervention here is that the the relevant code in
commit.c has been manually re-indented.

Suggested-by: Phillip Wood <phillip.wood123@gmail.com>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-04-13 23:56:08 -07:00
Ævar Arnfjörð Bjarmason
89ef49b30c object-store.h: remove unused has_sha1_file*()
These macros were last used in 5d3679ee02 (sha1-file: drop
has_sha1_file(), 2019-01-07), so let's remove coccinelle migration
rules added 9b45f49981 (object-store: prepare has_{sha1, object}_file
to handle any repo, 2018-11-13), along with the compatibility macros
themselves.

The "These functions.." in the diff context and the general comment
about compatibility macros still applies to
"NO_THE_REPOSITORY_COMPATIBILITY_MACROS" use just a few lines below
this, so let's keep the comment.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-04-01 10:16:10 -07:00
Johannes Schindelin
22184af2cb cocci: allow padding with strbuf_addf()
A convenient way to pad strings is to use something like
`strbuf_addf(&buf, "%20s", "Hello, world!")`.

However, the Coccinelle rule that forbids a format `"%s"` with a
constant string argument cast too wide a net, and also forbade such
padding.

The original rule was introduced by commit:

    28c23cd4c3 (strbuf.cocci: suggest strbuf_addbuf() to add one strbuf to an other, 2019-01-25)

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Teng Long <dyroneteng@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-03-23 11:38:40 -07:00
René Scharfe
6346f704a0 index-pack: use xopen in init_thread
Support an arbitrary file descriptor expression in the semantic patch
for replacing open+die_errno with xopen, not just an identifier, and
apply it.  This makes the error message at the single affected place
more consistent and reduces code duplication.

Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-10 14:22:50 -07:00
René Scharfe
66e905b7dd use xopen() to handle fatal open(2) failures
Add and apply a semantic patch for using xopen() instead of calling
open(2) and die() or die_errno() explicitly.  This makes the error
messages more consistent and shortens the code.

Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-08-25 14:39:08 -07:00
Junio C Hamano
bfcc6e2a68 Merge branch 'rs/xcalloc-takes-nelem-first'
Code cleanup.

* rs/xcalloc-takes-nelem-first:
  fix xcalloc() argument order
2021-03-19 15:25:39 -07:00
Junio C Hamano
1c57cc70ec cocci: allow xcalloc(1, size)
Allocating a pre-cleared single element is quite common and it is
misleading to use CALLOC_ARRAY(); these allocations that would be
affected without this change are not allocating an array.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-03-15 17:56:07 -07:00
René Scharfe
ca56dadb4b use CALLOC_ARRAY
Add and apply a semantic patch for converting code that open-codes
CALLOC_ARRAY to use it instead.  It shortens the code and infers the
element size automatically.

Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-03-13 16:00:09 -08:00
René Scharfe
241b5d3ebe fix xcalloc() argument order
Pass the number of elements first and ther size second, as expected
by xcalloc().  Provide a semantic patch, which was actually used to
generate the rest of this patch.

The semantic patch would generate flip-flop diffs if both arguments
are sizeofs.  We don't have such a case, and it's hard to imagine
the usefulness of such an allocation.  If it ever occurs then we
could deal with it by duplicating the rule in the semantic patch to
make it cancel itself out, or we could change the code to use
CALLOC_ARRAY.

Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-03-08 09:45:04 -08:00
Abhishek Kumar
c49c82aa4c commit: move members graph_pos, generation to a slab
We remove members `graph_pos` and `generation` from the struct commit.
The default assignments in init_commit_node() are no longer valid,
which is fine as the slab helpers return appropriate default values and
the assignments are removed.

We will replace existing use of commit->generation and commit->graph_pos
by commit_graph_data_slab helpers using
`contrib/coccinelle/commit.cocci'.

Signed-off-by: Abhishek Kumar <abhishekkumar8222@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-06-17 14:37:30 -07:00
Junio C Hamano
f165457618 Merge branch 'jk/remove-sha1-to-hex'
Code clean-up.

* jk/remove-sha1-to-hex:
  hex: drop sha1_to_hex()
  hex: drop sha1_to_hex_r()
2019-12-01 09:04:36 -08:00
Jeff King
b19f3fe9dd hex: drop sha1_to_hex()
There's only a single caller left of sha1_to_hex(), since everybody
that has an object name in "unsigned char[]" now uses hash_to_hex()
instead.

This case is in the sha1dc wrapper, where we print a hex sha1 when
we find a collision. This one will always be sha1, regardless of the
current hash algorithm, so we can't use hash_to_hex() here. In
practice we'd probably not be running sha1 at all if it isn't the
current algorithm, but it's possible we might still occasionally
need to compute a sha1 in a post-sha256 world.

Since sha1_to_hex() is just a wrapper for hash_to_hex_algop(), let's
call that ourselves. There's value in getting rid of the sha1-specific
wrapper to de-clutter the global namespace, and to make sure nobody uses
it (and as with sha1_to_hex_r() in the previous patch, we'll drop the
coccinelle transformations, too).

The sha1_to_hex() function is mentioned in a comment; we can easily
swap that out for oid_to_hex() to give a better example.  Also
update the comment that was left stale when we added "struct
object_id *" as a way to name an object and added functions to
convert it to hex.

The function is also mentioned in some test vectors in t4100, but
that's not runnable code, so there's no point in trying to clean it
up.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-11-13 10:09:10 +09:00
Jeff King
aa6d7f93ed hex: drop sha1_to_hex_r()
There are no callers left; everybody uses oid_to_hex_r() or
hash_to_hex_algop_r(). This used to actually be the underlying
implementation for oid_to_hex_r(), but that's no longer the case since
47edb64997 (hex: introduce functions to print arbitrary hashes,
2018-11-14).

Let's get rid of it to de-clutter and to make sure nobody uses it.
Likewise we can drop the coccinelle rules that mention it, since the
compiler will make it quite clear that the code does not work.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-11-11 18:11:41 +09:00
Elijah Newren
15beaaa3d1 Fix spelling errors in code comments
Reported-by: Jens Schleusener <Jens.Schleusener@fossies.org>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-11-10 16:00:54 +09:00
Eric Wong
12878c8351 coccicheck: detect hashmap_entry.hash assignment
Assigning hashmap_entry.hash manually leaves hashmap_entry.next
uninitialized, which can be dangerous once the hashmap_entry is
inserted into a hashmap.   Detect those assignments and use
hashmap_entry_init, instead.

Signed-off-by: Eric Wong <e@80x24.org>
Reviewed-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-10-07 10:20:09 +09:00
René Scharfe
177fbab747 coccinelle: use COPY_ARRAY for copying arrays
The current semantic patch for COPY_ARRAY transforms memcpy(3) calls on
pointers, but Coccinelle distinguishes them from arrays.  It already
contains three rules to handle the options for sizeof (i.e. source,
destination and type), and handling arrays as source and destination
would require four times as many rules if we enumerated all cases.

We also don't handle array subscripts, and supporting that would
increase the number of rules by another factor of four.  (An isomorphism
telling Coccinelle that "sizeof x[...]" is equivalent to "sizeof *x"
would be nice..)

Support arrays and array subscripts, but keep the number of rules down
by adding normalization steps: First turn array subscripts into
derefences, then determine the types of expressions used with sizeof and
replace them with these types, and then convert the different possible
combinations of arrays and pointers with memcpy(3) to COPY_ARRAY.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-06-17 18:14:59 -07:00
Junio C Hamano
0b179f3175 Merge branch 'nd/sha1-name-c-wo-the-repository'
Further code clean-up to allow the lowest level of name-to-object
mapping layer to work with a passed-in repository other than the
default one.

* nd/sha1-name-c-wo-the-repository: (34 commits)
  sha1-name.c: remove the_repo from get_oid_mb()
  sha1-name.c: remove the_repo from other get_oid_*
  sha1-name.c: remove the_repo from maybe_die_on_misspelt_object_name
  submodule-config.c: use repo_get_oid for reading .gitmodules
  sha1-name.c: add repo_get_oid()
  sha1-name.c: remove the_repo from get_oid_with_context_1()
  sha1-name.c: remove the_repo from resolve_relative_path()
  sha1-name.c: remove the_repo from diagnose_invalid_index_path()
  sha1-name.c: remove the_repo from handle_one_ref()
  sha1-name.c: remove the_repo from get_oid_1()
  sha1-name.c: remove the_repo from get_oid_basic()
  sha1-name.c: remove the_repo from get_describe_name()
  sha1-name.c: remove the_repo from get_oid_oneline()
  sha1-name.c: add repo_interpret_branch_name()
  sha1-name.c: remove the_repo from interpret_branch_mark()
  sha1-name.c: remove the_repo from interpret_nth_prior_checkout()
  sha1-name.c: remove the_repo from get_short_oid()
  sha1-name.c: add repo_for_each_abbrev()
  sha1-name.c: store and use repo in struct disambiguate_state
  sha1-name.c: add repo_find_unique_abbrev_r()
  ...
2019-05-09 00:37:25 +09:00
Nguyễn Thái Ngọc Duy
301b8c7f40 commit.c: add repo_get_commit_tree()
Remove the implicit dependency on the_repository in this function.
It will be used in sha1-name.c functions when they are updated to take
any 'struct repository'. get_commit_tree() remains as a compat wrapper,
to be slowly replaced later.

Any access to "maybe_tree" field directly will result in _broken_ code
after running through commit.cocci because we can't know what is the
right repository to use.

the_repository would be correct most of the time. But we're relying less
and less on the_repository and that assumption may no longer be
true. The transformation now is more of a poor man replacement for a C++
compiler catching access to private fields.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-04-16 18:56:51 +09:00