Commit Graph

1421 Commits

Author SHA1 Message Date
Phillip Wood
76e32d6193 diff: simplify allow-indentation-change delta calculation
Now that we reliably end a block when the sign changes we don't need
the whitespace delta calculation to rely on the sign.

Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-12-09 13:24:05 -08:00
Phillip Wood
eb89352504 diff --color-moved: avoid false short line matches and bad zebra coloring
When marking moved lines it is possible for a block of potential
matched lines to extend past a change in sign when there is a sequence
of added lines whose text matches the text of a sequence of deleted
and added lines. Most of the time either `match` will be NULL or
`pmb_advance_or_null()` will fail when the loop encounters a change of
sign but there are corner cases where `match` is non-NULL and
`pmb_advance_or_null()` successfully advances the moved block despite
the change in sign.

One consequence of this is highlighting a short line as moved when it
should not be. For example

-moved line  # Correctly highlighted as moved
+short line  # Wrongly highlighted as moved
 context
+moved line  # Correctly highlighted as moved
+short line
 context
-short line

The other consequence is coloring a moved addition following a moved
deletion in the wrong color. In the example below the first "+moved
line 3" should be highlighted as newMoved not newMovedAlternate.

-moved line 1 # Correctly highlighted as oldMoved
-moved line 2 # Correctly highlighted as oldMovedAlternate
+moved line 3 # Wrongly highlighted as newMovedAlternate
 context      # Everything else is highlighted correctly
+moved line 2
+moved line 3
 context
+moved line 1
-moved line 3

These false matches are more likely when using --color-moved-ws with
the exception of --color-moved-ws=allow-indentation-change which ties
the sign of the current whitespace delta to the sign of the line to
avoid this problem. The fix is to check that the sign of the new line
being matched is the same as the sign of the line that started the
block of potential matches.

Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-12-09 13:24:05 -08:00
Phillip Wood
eb315457f6 diff --color-moved=zebra: fix alternate coloring
b0a2ba4776 ("diff --color-moved=zebra: be stricter with color
alternation", 2018-11-23) sought to avoid using the alternate colors
unless there are two adjacent moved blocks of the same
sign. Unfortunately it contains two bugs that prevented it from fixing
the problem properly. Firstly `last_symbol` is reset at the start of
each iteration of the loop losing the symbol of the last line and
secondly when deciding whether to use the alternate color it should be
checking if the current line is the same sign of the last line, not a
different sign. The combination of the two errors means that we still
use the alternate color when we should do but we also use it when we
shouldn't. This is most noticable when using
--color-moved-ws=allow-indentation-change with hunks like

-this line gets indented
+    this line gets indented

where the post image is colored with newMovedAlternate rather than
newMoved. While this does not matter much, the next commit will change
the coloring to be correct in this case, so lets fix the bug here to
make it clear why the output is changing and add a regression test.

Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-12-09 13:24:05 -08:00
Phillip Wood
0990658bf8 diff --color-moved: rewind when discarding pmb
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-12-09 13:24:05 -08:00
Phillip Wood
7dfe427107 diff --color-moved: factor out function
This code is quite heavily indented and having it in its own function
simplifies an upcoming change.

Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-12-09 13:24:05 -08:00
Phillip Wood
bea084ba41 diff --color-moved: clear all flags on blocks that are too short
If a block of potentially moved lines is not long enough then the
DIFF_SYMBOL_MOVED_LINE flag is cleared on the matching lines so they
are not marked as moved. To avoid problems when we start rewinding
after an unsuccessful match in a couple of commits time make sure all
the move related flags are cleared, not just DIFF_SYMBOL_MOVED_LINE.

Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-12-09 13:24:05 -08:00
Junio C Hamano
65c18913de Merge branch 'pw/word-diff-zero-width-matches'
The word-diff mode has been taught to work better with a word
regexp that can match an empty string.

* pw/word-diff-zero-width-matches:
  word diff: handle zero length matches
2021-05-14 08:26:06 +09:00
Phillip Wood
0324e8fc6b word diff: handle zero length matches
If find_word_boundaries() encounters a zero length match (which can be
caused by matching a newline or using '*' instead of '+' in the regex)
we stop splitting the input into words which generates an inaccurate
diff. To fix this increment the start point when there is a zero
length match and try a new match. This is safe as posix regular
expressions always return the longest available match so a zero length
match means there are no longer matches available from the current
position.

Commit bf82940dbf (color-words: enable REG_NEWLINE to help user,
2009-01-17) prevented matching newlines in negated character classes
but it is still possible for the user to have an explicit newline
match in the regex which could cause a zero length match.

One could argue that having explicit newline matches or using '*'
rather than '+' are user errors but it seems to be better to work
round them than produce inaccurate diffs.

Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-05-05 18:53:42 +09:00
brian m. carlson
14228447c9 hash: provide per-algorithm null OIDs
Up until recently, object IDs did not have an algorithm member, only a
hash.  Consequently, it was possible to share one null (all-zeros)
object ID among all hash algorithms.  Now that we're going to be
handling objects from multiple hash algorithms, it's important to make
sure that all object IDs have a correct algorithm field.

Introduce a per-algorithm null OID, and add it to struct hash_algo.
Introduce a wrapper function as well, and use it everywhere we used to
use the null_oid constant.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-04-27 16:31:39 +09:00
brian m. carlson
5951bf467e Use the final_oid_fn to finalize hashing of object IDs
When we're hashing a value which is going to be an object ID, we want to
zero-pad that value if necessary.  To do so, use the final_oid_fn
instead of the final_fn anytime we're going to create an object ID to
ensure we perform this operation.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-04-27 16:31:38 +09:00
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
Junio C Hamano
845d6030f8 Merge branch 'jc/diffcore-rotate'
"git {diff,log} --{skip,rotate}-to=<path>" allows the user to
discard diff output for early paths or move them to the end of the
output.

* jc/diffcore-rotate:
  diff: --{rotate,skip}-to=<path>
2021-02-25 16:43:30 -08:00
Junio C Hamano
1eb4136ac2 diff: --{rotate,skip}-to=<path>
In the implementation of "git difftool", there is a case where the
user wants to start viewing the diffs at a specific path and
continue on to the rest, optionally wrapping around to the
beginning.  Since it is somewhat cumbersome to implement such a
feature as a post-processing step of "git diff" output, let's
support it internally with two new options.

 - "git diff --rotate-to=C", when the resulting patch would show
   paths A B C D E without the option, would "rotate" the paths to
   shows patch to C D E A B instead.  It is an error when there is
   no patch for C is shown.

 - "git diff --skip-to=C" would instead "skip" the paths before C,
   and shows patch to C D E.  Again, it is an error when there is no
   patch for C is shown.

 - "git log [-p]" also accepts these two options, but it is not an
   error if there is no change to the specified path.  Instead, the
   set of output paths are rotated or skipped to the specified path
   or the first path that sorts after the specified path.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-02-16 09:30:42 -08:00
Ævar Arnfjörð Bjarmason
c45dc9cf30 diff: plug memory leak from regcomp() on {log,diff} -I
Fix a memory leak in 296d4a94e7 (diff: add -I<regex> that ignores
matching changes, 2020-10-20) by freeing the memory it allocates in
the newly introduced diff_free(). See the previous commit for details
on that.

This memory leak was intentionally introduced in 296d4a94e7, see the
discussion on a previous iteration of it in
https://lore.kernel.org/git/xmqqeelycajx.fsf@gitster.c.googlers.com/

At that time freeing the memory was somewhat tedious, but since it
isn't anymore with the newly introduced diff_free() let's use it.

Let's retain the pattern for diff_free_file() and add a
diff_free_ignore_regex(), even though (unlike "diff_free_file") we
don't need to call it elsewhere. I think this'll make for more
readable code than gradually accumulating a giant diff_free()
function, sharing "int i" across unrelated code etc.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-02-11 09:21:07 -08:00
Ævar Arnfjörð Bjarmason
e900d494dc diff: add an API for deferred freeing
Add a diff_free() function to free anything we may have allocated in
the "diff_options" struct, and the ability to make calling it a noop
by setting "no_free" in "diff_options".

This is required because when e.g. "git diff" is run we'll allocate
things in that struct, use the diff machinery once, and then exit.

But if we run e.g. "git log -p" we're going to re-use what we
allocated across multiple diff_flush() calls, and only want to free
things at the end.

We've thus ended up with features like the recently added "diff -I"[1]
where we'll leak memory. As it turns out it could have simply used the
pattern established in 6ea57703f6 (log: prepare log/log-tree to reuse
the diffopt.close_file attribute, 2016-06-22).

Manually adding more such flags to things log_tree_commit() every time
we need to allocate something would be tedious. Let's instead move
that fclose() code it to a new diff_free(), in anticipation of freeing
more things in that function in follow-up commits.

Some functions such as log_tree_commit() need an idiom of optionally
retaining a previous "no_free", as they may either free the memory
themselves, or their caller may do so. I'm keeping that idiom in
log_show_early() for good measure, even though I don't think it's
currently called in this manner. It also gets passed an existing
"struct rev_info", so future callers may want to set the "no_free"
flag.

This change is a bit hard to read because while the freeing pattern
we're introducing isn't unusual, the "file" member is a special
snowflake. We usually don't want to fclose() it. This is because
"file" is usually stdout, in which case we don't want to fclose()
it. We only want to opt-in to closing it when we e.g. open a file on
the filesystem. Thus the opt-in "close_file" flag.

So the API in general just needs a "no_free" flag to defer freeing,
but the "file" member still needs its "close_file" flag. This is made
more confusing because while refactoring this code we could replace
some "close_file=0" with "no_free=1", whereas others need to set both
flags.

This is because there were some cases where an existing "close_file=0"
meant "let's defer deallocation", and others where it meant "we don't
want to close this file handle at all".

1. 296d4a94e7 (diff: add -I<regex> that ignores matching changes,
   2020-10-20)

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-02-11 09:21:05 -08:00
Junio C Hamano
0806279428 Merge branch 'sj/untracked-files-in-submodule-directory-is-not-dirty'
"git diff" showed a submodule working tree with untracked cruft as
"Submodule commit <objectname>-dirty", but a natural expectation is
that the "-dirty" indicator would align with "git describe --dirty",
which does not consider having untracked files in the working tree
as source of dirtiness.  The inconsistency has been fixed.

* sj/untracked-files-in-submodule-directory-is-not-dirty:
  diff: do not show submodule with untracked files as "-dirty"
2021-01-25 14:19:18 -08:00
Junio C Hamano
59fcf746f5 Merge branch 'jc/diff-I-status-fix'
"git diff -I<pattern> -exit-code" should exit with 0 status when
all the changes match the ignored pattern, but it didn't.

* jc/diff-I-status-fix:
  diff: correct interaction between --exit-code and -I<pattern>
2020-12-18 15:15:18 -08:00
Junio C Hamano
50f0439490 diff: correct interaction between --exit-code and -I<pattern>
Just like "git diff -w --exit-code" should exit with 0 when ignoring
whitespace differences results in no changes shown, if ignoring
certain changes with "git diff -I<pattern> --exit-code" result in an
empty patch, we should exit with 0.

The test suite did not cover the interaction between "--exit-code"
and "-w"; add one while adding a new test for "--exit-code" + "-I".

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-12-16 17:33:26 -08:00
Sangeeta Jain
8ef9312464 diff: do not show submodule with untracked files as "-dirty"
Git diff reports a submodule directory as -dirty even when there are
only untracked files in the submodule directory. This is inconsistent
with what `git describe --dirty` says when run in the submodule
directory in that state.

Make `--ignore-submodules=untracked` the default for `git diff` when
there is no configuration variable or command line option, so that the
command would not give '-dirty' suffix to a submodule whose working
tree has untracked files, to make it consistent with `git
describe --dirty` that is run in the submodule working tree.

And also make `--ignore-submodules=none` the default for `git status`
so that the user doesn't end up deleting a submodule that has
uncommitted (untracked) files.

Signed-off-by: Sangeeta Jain <sangunb09@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-12-08 14:27:35 -08:00
Junio C Hamano
bf0a430f70 Merge branch 'en/strmap'
A specialization of hashmap that uses a string as key has been
introduced.  Hopefully it will see wider use over time.

* en/strmap:
  shortlog: use strset from strmap.h
  Use new HASHMAP_INIT macro to simplify hashmap initialization
  strmap: take advantage of FLEXPTR_ALLOC_STR when relevant
  strmap: enable allocations to come from a mem_pool
  strmap: add a strset sub-type
  strmap: split create_entry() out of strmap_put()
  strmap: add functions facilitating use as a string->int map
  strmap: enable faster clearing and reusing of strmaps
  strmap: add more utility functions
  strmap: new utility functions
  hashmap: provide deallocation function names
  hashmap: introduce a new hashmap_partial_clear()
  hashmap: allow re-use after hashmap_free()
  hashmap: adjust spacing to fix argument alignment
  hashmap: add usage documentation explaining hashmap_free[_entries]()
2020-11-21 15:14:38 -08:00
Junio C Hamano
d5e35329dd Merge branch 'jk/diff-release-filespec-fix'
Running "git diff" while allowing external diff in a state with
unmerged paths used to segfault, which has been corrected.

* jk/diff-release-filespec-fix:
  t7800: simplify difftool test
  diff: allow passing NULL to diff_free_filespec_data()
2020-11-21 15:14:38 -08:00
Jinoh Kang
246959346f diff: allow passing NULL to diff_free_filespec_data()
Commit 3aef54e8b8 ("diff: munmap() file contents before running external
diff") introduced calls to diff_free_filespec_data in
run_external_diff, which may pass NULL pointers.

Fix this and prevent any such bugs in the future by making
`diff_free_filespec_data(NULL)` a no-op.

Fixes: 3aef54e8b8 ("diff: munmap() file contents before running external diff")
Signed-off-by: Jinoh Kang <luke1337@theori.io>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-11-06 11:37:07 -08:00
Junio C Hamano
1ae0949a03 Merge branch 'mk/diff-ignore-regex'
"git diff" family of commands learned the "-I<regex>" option to
ignore hunks whose changed lines all match the given pattern.

* mk/diff-ignore-regex:
  diff: add -I<regex> that ignores matching changes
  merge-base, xdiff: zero out xpparam_t structures
2020-11-02 13:17:44 -08:00
Elijah Newren
6da1a25814 hashmap: provide deallocation function names
hashmap_free(), hashmap_free_entries(), and hashmap_free_() have existed
for a while, but aren't necessarily the clearest names, especially with
hashmap_partial_clear() being added to the mix and lazy-initialization
now being supported.  Peff suggested we adopt the following names[1]:

  - hashmap_clear() - remove all entries and de-allocate any
    hashmap-specific data, but be ready for reuse

  - hashmap_clear_and_free() - ditto, but free the entries themselves

  - hashmap_partial_clear() - remove all entries but don't deallocate
    table

  - hashmap_partial_clear_and_free() - ditto, but free the entries

This patch provides the new names and converts all existing callers over
to the new naming scheme.

[1] https://lore.kernel.org/git/20201030125059.GA3277724@coredump.intra.peff.net/

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-11-02 12:15:50 -08:00
Michał Kępień
296d4a94e7 diff: add -I<regex> that ignores matching changes
Add a new diff option that enables ignoring changes whose all lines
(changed, removed, and added) match a given regular expression.  This is
similar to the -I/--ignore-matching-lines option in standalone diff
utilities and can be used e.g. to ignore changes which only affect code
comments or to look for unrelated changes in commits containing a large
number of automatically applied modifications (e.g. a tree-wide string
replacement).  The difference between -G/-S and the new -I option is
that the latter filters output on a per-change basis.

Use the 'ignore' field of xdchange_t for marking a change as ignored or
not.  Since the same field is used by --ignore-blank-lines, identical
hunk emitting rules apply for --ignore-blank-lines and -I.  These two
options can also be used together in the same git invocation (they are
complementary to each other).

Rename xdl_mark_ignorable() to xdl_mark_ignorable_lines(), to indicate
that it is logically a "sibling" of xdl_mark_ignorable_regex() rather
than its "parent".

Signed-off-by: Michał Kępień <michal@isc.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-10-20 12:53:26 -07:00
Thomas Guyot-Sionnest
ff0c7fa8cb diff: fix modified lines stats with --stat and --numstat
Only skip diffstats when both oids are valid and identical. This check
was causing both false-positives (files included in diffstats with no
actual changes (0 lines modified) and false-negatives (showing 0 lines
modified in stats when files had actually changed).

Also replaced same_contents with may_differ to avoid confusion.

Signed-off-by: Thomas Guyot-Sionnest <tguyot@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-24 12:31:45 -07:00
Junio C Hamano
9d4e7ec4d9 Merge branch 'jc/quote-path-cleanup'
"git status --short" quoted a path with SP in it when tracked, but
not those that are untracked, ignored or unmerged.  They are all
shown quoted consistently.

* jc/quote-path-cleanup:
  quote: turn 'nodq' parameter into a set of flags
  quote: rename misnamed sq_lookup[] to cq_lookup[]
  wt-status: consistently quote paths in "status --short" output
  quote_path: code clarification
  quote_path: optionally allow quoting a path with SP in it
  quote_path: give flags parameter to quote_path()
  quote_path: rename quote_path_relative() to quote_path()
2020-09-18 17:58:04 -07:00
Junio C Hamano
7c37c9750a quote: turn 'nodq' parameter into a set of flags
quote_c_style() and its friend quote_two_c_style() both take an
optional "please omit the double quotes around the quoted body"
parameter.  Turn it into a flag word, assign one bit out of it,
and call it CQUOTE_NODQ bit.

No behaviour change intended.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-10 13:08:07 -07:00
Junio C Hamano
bbdba3d883 Merge branch 'ss/submodule-summary-in-c'
Yet another subcommand of "git submodule" is getting rewritten in C.

* ss/submodule-summary-in-c:
  submodule: port submodule subcommand 'summary' from shell to C
  t7421: introduce a test script for verifying 'summary' output
  submodule: rename helper functions to avoid ambiguity
  submodule: remove extra line feeds between callback struct and macro
2020-09-09 13:53:05 -07:00
Junio C Hamano
b58e47a929 Merge branch 'mr/diff-hide-stat-wo-textual-change'
"git diff --stat -w" showed 0-line changes for paths whose changes
were only whitespaces, which was not intuitive.  We now omit such
paths from the stat output.

* mr/diff-hide-stat-wo-textual-change:
  diff: teach --stat to ignore uninteresting modifications
2020-09-03 12:37:05 -07:00
Junio C Hamano
096c948dab Merge branch 'dd/diff-customize-index-line-abbrev'
The output from the "diff" family of the commands had abbreviated
object names of blobs involved in the patch, but its length was not
affected by the --abbrev option.  Now it is.

* dd/diff-customize-index-line-abbrev:
  diff: index-line: respect --abbrev in object's name
  t4013: improve diff-post-processor logic
2020-08-31 15:49:46 -07:00
Junio C Hamano
51226147d1 Merge branch 'rs/patch-id-with-incomplete-line'
The patch-id computation did not ignore the "incomplete last line"
marker like whitespaces.

* rs/patch-id-with-incomplete-line:
  patch-id: ignore newline at end of file in diff_flush_patch_id()
2020-08-24 14:54:33 -07:00
Đoàn Trần Công Danh
3046c7f69a diff: index-line: respect --abbrev in object's name
A handful of Git's commands respect `--abbrev' for customizing length
of abbreviation of object names.

For diff-family, Git supports 2 different options for 2 different
purposes, `--full-index' for showing diff-patch object's name in full,
and `--abbrev' to customize the length of object names in diff-raw and
diff-tree header lines, without any options to customise the length of
object names in diff-patch format. When working with diff-patch format,
we only have two options, either full index, or default abbrev length.

Although, that behaviour is documented, it doesn't stop users from
trying to use `--abbrev' with the hope of customising diff-patch's
objects' name's abbreviation.

Let's allow the blob object names shown on the "index" line to be
abbreviated to arbitrary length given via the "--abbrev" option.

To preserve backward compatibility with old script that specify both
`--full-index' and `--abbrev', always show full object id
if `--full-index' is specified.

Signed-off-by: Đoàn Trần Công Danh <congdanhqx@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-08-21 12:43:05 -07:00
Matthew Rogers
1cf3d5db9b diff: teach --stat to ignore uninteresting modifications
When options such as --ignore-space-change are in use, files with
modifications can have no interesting textual changes worth showing.  In
such cases, "git diff --stat" shows 0 lines of additions and deletions.
Teach "git diff --stat" not to show such a path in its output, which
would be more natural.

However, we don't want to prevent the display  of all files that have 0
effective diffs since they could be the result of a rename, permission
change, or other similar operation that may still be of interest so we
special case additions and deletions as they are always interesting.

Signed-off-by: Matthew Rogers <mattr94@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-08-19 17:53:32 -07:00
René Scharfe
82a62015a7 patch-id: ignore newline at end of file in diff_flush_patch_id()
Whitespace is ignored when calculating patch IDs.  This is done by
removing all whitespace from diff lines before hashing them, including
a newline at the end of a file.  If that newline is missing, however,
diff reports that fact in a separate line containing "\ No newline at
end of file\n", and this marker is hashed like a context line.

This goes against our goal of making patch IDs independent of
whitespace.  Use the same heuristic that 2485eab55c (git-patch-id: do
not trip over "no newline" markers, 2011-02-17) added to git patch-id
instead and skip diff lines that start with a backslash and a space
and are longer than twelve characters.

Reported-by: Tilman Vogel <tilman.vogel@web.de>
Initial-test-by: Tilman Vogel <tilman.vogel@web.de>
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-08-18 16:14:01 -07:00
Shourya Shukla
180b154b09 submodule: rename helper functions to avoid ambiguity
The helper functions: show_submodule_summary(),
prepare_submodule_summary() and print_submodule_summary() are used by
the builtin_diff() function in diff.c to generate a summary of
submodules in the context of a diff. Functions with similar names are to
be introduced in the upcoming port of submodule's summary subcommand.

So, rename the helper functions to '*_diff_submodule_summary()' to avoid
ambiguity.

Mentored-by: Christian Couder <chriscool@tuxfamily.org>
Mentored-by: Kaartic Sivaraam <kaartic.sivaraam@gmail.com>
Signed-off-by: Shourya Shukla <shouryashukla.oo@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-08-12 14:12:58 -07:00
Jeff King
d70a9eb611 strvec: rename struct fields
The "argc" and "argv" names made sense when the struct was argv_array,
but now they're just confusing. Let's rename them to "nr" (which we use
for counts elsewhere) and "v" (which is rather terse, but reads well
when combined with typical variable names like "args.v").

Note that we have to update all of the callers immediately. Playing
tricks with the preprocessor is hard here, because we wouldn't want to
rewrite unrelated tokens.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-07-30 19:18:06 -07:00
Jeff King
ef8d7ac42a strvec: convert more callers away from argv_array name
We eventually want to drop the argv_array name and just use strvec
consistently. There's no particular reason we have to do it all at once,
or care about interactions between converted and unconverted bits.
Because of our preprocessor compat layer, the names are interchangeable
to the compiler (so even a definition and declaration using different
names is OK).

This patch converts remaining files from the first half of the alphabet,
to keep the diff to a manageable size.

The conversion was done purely mechanically with:

  git ls-files '*.c' '*.h' |
  xargs perl -i -pe '
    s/ARGV_ARRAY/STRVEC/g;
    s/argv_array/strvec/g;
  '

and then selectively staging files with "git add '[abcdefghjkl]*'".
We'll deal with any indentation/style fallouts separately.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-07-28 15:02:18 -07:00
Jeff King
dbbcd44fb4 strvec: rename files from argv-array to strvec
This requires updating #include lines across the code-base, but that's
all fairly mechanical, and was done with:

  git ls-files '*.c' '*.h' |
  xargs perl -i -pe 's/argv-array.h/strvec.h/'

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-07-28 15:02:17 -07:00
Junio C Hamano
0cd0afc9c6 Merge branch 'jk/diff-memuse-optim-with-stat-unmatch'
Reduce memory usage during "diff --quiet" in a worktree with too
many stat-unmatched paths.

* jk/diff-memuse-optim-with-stat-unmatch:
  diff: discard blob data from stat-unmatched pairs
2020-06-17 21:54:00 -07:00
Jeff King
d2d7fbe129 diff: discard blob data from stat-unmatched pairs
When performing a tree-level diff against the working tree, we may find
that our index stat information is dirty, so we queue a filepair to be
examined later. If the actual content hasn't changed, we call this a
stat-unmatch; the stat information was out of date, but there's no
actual diff.  Normally diffcore_std() would detect and remove these
identical filepairs via diffcore_skip_stat_unmatch().  However, when
"--quiet" is used, we want to stop the diff as soon as we see any
changes, so we check for stat-unmatches immediately in diff_change().

That check may require us to actually load the file contents into the
pair of diff_filespecs. If we find that the pair isn't a stat-unmatch,
then no big deal; we'd likely load the contents later anyway to generate
a patch, do rename detection, etc, so we want to hold on to it. But if
it is a stat-unmatch, then we have no more use for that data; the whole
point is that we're going discard the pair. However, we never free the
allocated diff_filespec data.

In most cases, keeping that data isn't a problem. We don't expect a lot
of stat-unmatch entries, and since we're using --quiet, we'd quit as
soon as we saw such a real change anyway. However, there are extreme
cases where it makes a big difference:

  1. We'd generally mmap() the working tree half of the pair. And since
     the OS may limit the total number of maps, we can run afoul of this
     in large repositories. E.g.:

       $ cd linux
       $ git ls-files | wc -l
       67959
       $ sysctl vm.max_map_count
       vm.max_map_count = 65530
       $ git ls-files | xargs touch ;# everything is stat-dirty!
       $ git diff --quiet
       fatal: mmap failed: Cannot allocate memory

     It should be unusual to have so many files stat-dirty, but it's
     possible if you've just run a script like "sed -i" or similar.

     After this patch, the above correctly exits with code 0.

  2. Even if you don't hit mmap limits, the index half of the pair will
     have been pulled from the object database into heap memory. Again
     in a clone of linux.git, running:

       $ git ls-files | head -n 10000 | xargs touch
       $ git diff --quiet

     peaks at 145MB heap before this patch, and 94MB after.

This patch solves the problem by freeing any diff_filespec data we
picked up during the "--quiet" stat-unmatch check in diff_changes.
Nobody is going to need that data later, so there's no point holding on
to it. There are a few things to note:

  - we could skip queueing the pair entirely, which could in theory save
    a little work. But there's not much to save, as we need a
    diff_filepair to feed to diff_filespec_check_stat_unmatch() anyway.
    And since we cache the result of the stat-unmatch checks, a later
    call to diffcore_skip_stat_unmatch() call will quickly skip over
    them. The diffcore code also counts up the number of stat-unmatched
    pairs as it removes them. It's doubtful any callers would care about
    that in combination with --quiet, but we'd have to reimplement the
    logic here to be on the safe side. So it's not really worth the
    trouble.

  - I didn't write a test, because we always produce the correct output
    unless we run up against system mmap limits, which are both
    unportable and expensive to test against. Measuring peak heap
    would be interesting, but our perf suite isn't yet capable of that.

  - note that diff without "--quiet" does not suffer from the same
    problem. In diffcore_skip_stat_unmatch(), we detect the stat-unmatch
    entries and drop them immediately, so we're not carrying their data
    around.

  - you _can_ still trigger the mmap limit problem if you truly have
    that many files with actual changes. But it's rather unlikely. The
    stat-unmatch check avoids loading the file contents if the sizes
    don't match, so you'd need a pretty trivial change in every single
    file. Likewise, inexact rename detection might load the data for
    many files all at once. But you'd need not just 64k changes, but
    that many deletions and additions. The most likely candidate is
    perhaps break-detection, which would load the data for all pairs and
    keep it around for the content-level diff. But again, you'd need 64k
    actually changed files in the first place.

    So it's still possible to trigger this case, but it seems like "I
    accidentally made all my files stat-dirty" is the most likely case
    in the real world.

Reported-by: Jan Christoph Uhde <Jan@UhdeJc.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-06-02 09:28:56 -07:00
Laurent Arnoud
c28ded83fc diff: add config option relative
The `diff.relative` boolean option set to `true` shows only changes in
the current directory/value specified by the `path` argument of the
`relative` option and shows pathnames relative to the aforementioned
directory.

Teach `--no-relative` to override earlier `--relative`

Add for git-format-patch(1) options documentation `--relative` and
`--no-relative`

Signed-off-by: Laurent Arnoud <laurent@spkdev.net>
Acked-by: Đoàn Trần Công Danh <congdanhqx@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-05-24 16:23:59 -07:00
Junio C Hamano
8f5dc5a4af Merge branch 'jt/avoid-prefetch-when-able-in-diff'
"git diff" in a partial clone learned to avoid lazy loading blob
objects in more casese when they are not needed.

* jt/avoid-prefetch-when-able-in-diff:
  diff: restrict when prefetching occurs
  diff: refactor object read
  diff: make diff_populate_filespec_options struct
  promisor-remote: accept 0 as oid_nr in function
2020-04-28 15:50:04 -07:00
Jonathan Tan
95acf11a3d diff: restrict when prefetching occurs
Commit 7fbbcb21b1 ("diff: batch fetching of missing blobs", 2019-04-08)
optimized "diff" by prefetching blobs in a partial clone, but there are
some cases wherein blobs do not need to be prefetched. In these cases,
any command that uses the diff machinery will unnecessarily fetch blobs.

diffcore_std() may read blobs when it calls the following functions:
 (1) diffcore_skip_stat_unmatch() (controlled by the config variable
     diff.autorefreshindex)
 (2) diffcore_break() and diffcore_merge_broken() (for break-rewrite
     detection)
 (3) diffcore_rename() (for rename detection)
 (4) diffcore_pickaxe() (for detecting addition/deletion of specified
     string)

Instead of always prefetching blobs, teach diffcore_skip_stat_unmatch(),
diffcore_break(), and diffcore_rename() to prefetch blobs upon the first
read of a missing object. This covers (1), (2), and (3): to cover the
rest, teach diffcore_std() to prefetch if the output type is one that
includes blob data (and hence blob data will be required later anyway),
or if it knows that (4) will be run.

Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-04-07 16:09:29 -07:00
Jonathan Tan
c14b6f83ec diff: refactor object read
Refactor the object reads in diff_populate_filespec() to have the first
object read not be in an if/else branch, because in a future patch, a
retry will be added to that first object read.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-04-07 16:09:29 -07:00
Jonathan Tan
1c37e86ab2 diff: make diff_populate_filespec_options struct
The behavior of diff_populate_filespec() currently can be customized
through a bitflag, but a subsequent patch requires it to support a
non-boolean option. Replace the bitflag with an options struct.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-04-07 16:09:29 -07:00
Jonathan Tan
db7ed7418b promisor-remote: accept 0 as oid_nr in function
There are 3 callers to promisor_remote_get_direct() that first check if
the number of objects to be fetched is equal to 0. Fold that check into
promisor_remote_get_direct(), and in doing so, be explicit as to what
promisor_remote_get_direct() does if oid_nr is 0 (it returns 0, success,
immediately).

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-04-02 12:42:32 -07:00
brian m. carlson
c397aac02f convert: provide additional metadata to filters
Now that we have the codebase wired up to pass any additional metadata
to filters, let's collect the additional metadata that we'd like to
pass.

The two main places we pass this metadata are checkouts and archives.
In these two situations, reading HEAD isn't a valid option, since HEAD
isn't updated for checkouts until after the working tree is written and
archives can accept an arbitrary tree.  In other situations, HEAD will
usually reflect the refname of the branch in current use.

We pass a smaller amount of data in other cases, such as git cat-file,
where we can really only logically know about the blob.

This commit updates only the parts of the checkout code where we don't
use unpack_trees.  That function and callers of it will be handled in a
future commit.

In the archive code, we leak a small amount of memory, since nothing we
pass in the archiver argument structure is freed.

Signed-off-by: brian m. carlson <bk2204@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-03-16 11:37:02 -07:00
brian m. carlson
ab90ecae99 convert: permit passing additional metadata to filter processes
There are a variety of situations where a filter process can make use of
some additional metadata.  For example, some people find the ident
filter too limiting and would like to include the commit or the branch
in their smudged files.  This information isn't available during
checkout as HEAD hasn't been updated at that point, and it wouldn't be
available in archives either.

Let's add a way to pass this metadata down to the filter.  We pass the
blob we're operating on, the treeish (preferring the commit over the
tree if one exists), and the ref we're operating on.  Note that we won't
pass this information in all cases, such as when renormalizing or when
we're performing diffs, since it doesn't make sense in those cases.

The data we currently get from the filter process looks like the
following:

  command=smudge
  pathname=git.c
  0000

With this change, we'll get data more like this:

  command=smudge
  pathname=git.c
  refname=refs/tags/v2.25.1
  treeish=c522f061d551c9bb8684a7c3859b2ece4499b56b
  blob=7be7ad34bd053884ec48923706e70c81719a8660
  0000

There are a couple things to note about this approach.  For operations
like checkout, treeish will always be a commit, since we cannot check
out individual trees, but for other operations, like archive, we can end
up operating on only a particular tree, so we'll provide only a tree as
the treeish.  Similar comments apply for refname, since there are a
variety of cases in which we won't have a ref.

This commit wires up the code to print this information, but doesn't
pass any of it at this point.  In a future commit, we'll have various
code paths pass the actual useful data down.

Signed-off-by: brian m. carlson <bk2204@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-03-16 11:37:02 -07:00
Junio C Hamano
78e67cda42 Merge branch 'mt/use-passed-repo-more-in-funcs'
Some codepaths were given a repository instance as a parameter to
work in the repository, but passed the_repository instance to its
callees, which has been cleaned up (somewhat).

* mt/use-passed-repo-more-in-funcs:
  sha1-file: allow check_object_signature() to handle any repo
  sha1-file: pass git_hash_algo to hash_object_file()
  sha1-file: pass git_hash_algo to write_object_file_prepare()
  streaming: allow open_istream() to handle any repo
  pack-check: use given repo's hash_algo at verify_packfile()
  cache-tree: use given repo's hash_algo at verify_one()
  diff: make diff_populate_filespec() honor its repo argument
2020-02-14 12:54:22 -08:00