Refactor the "do not stop feeding the backend early" logic into a small
helper function and use it in both run_diff_files() and diff_tree() that
has the stop-early optimization. We may later add other types of diffcore
transformation that require to look at the whole result like diff-filter
does, and having the logic in a single place is essential for longer term
maintainability.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* jh/dirstat-lines:
Mark dirstat error messages for translation
Improve error handling when parsing dirstat parameters
New --dirstat=lines mode, doing dirstat analysis based on diffstat
Allow specifying --dirstat cut-off percentage as a floating point number
Add config variable for specifying default --dirstat behavior
Refactor --dirstat parsing; deprecate --cumulative and --dirstat-by-file
Make --dirstat=0 output directories that contribute < 0.1% of changes
Add several testcases for --dirstat and friends
* jc/fix-diff-files-unmerged:
diff-files: show unmerged entries correctly
diff: remove often unused parameters from diff_unmerge()
diff.c: return filepair from diff_unmerge()
test: use $_z40 from test-lib
This patch adds an alternative implementation of show_dirstat(), called
show_dirstat_by_line(), which uses the more expensive diffstat analysis
(as opposed to show_dirstat()'s own (relatively inexpensive) analysis)
to derive the numbers from which the --dirstat output is computed.
The alternative implementation is controlled by the new "lines" parameter
to the --dirstat option (or the diff.dirstat config variable).
For binary files, the diffstat analysis counts bytes instead of lines,
so to prevent binary files from dominating the dirstat results, the
byte counts for binary files are divided by 64 before being compared to
their textual/line-based counterparts. This is a stupid and ugly - but
very cheap - heuristic.
In linux-2.6.git, running the three different --dirstat modes:
time git diff v2.6.20..v2.6.30 --dirstat=changes > /dev/null
vs.
time git diff v2.6.20..v2.6.30 --dirstat=lines > /dev/null
vs.
time git diff v2.6.20..v2.6.30 --dirstat=files > /dev/null
yields the following average runtimes on my machine:
- "changes" (default): ~6.0 s
- "lines": ~9.6 s
- "files": ~0.1 s
So, as expected, there's a considerable performance hit (~60%) by going
through the full diffstat analysis as compared to the default "changes"
analysis (obviously, "files" is much faster than both). As such, the
"lines" mode is probably only useful if you really need the --dirstat
numbers to be consistent with the numbers returned from the other
--*stat options.
The patch also includes documentation and tests for the new dirstat mode.
Improved-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Johan Herland <johan@herland.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Only the first digit after the decimal point is kept, as the dirstat
calculations all happen in permille.
Selftests verifying floating-point percentage input has been added.
Improved-by: Junio C Hamano <gitster@pobox.com>
Improved-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Johan Herland <johan@herland.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
e9c8409 (diff-index --cached --raw: show tree entry on the LHS for
unmerged entries., 2007-01-05) added a <mode, object name> pair as
parameters to this function, to store them in the pre-image side of an
unmerged file pair. Now the function is fixed to return the filepair it
queued, we can make the caller on the special case codepath to do so.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The underlying diff_queue() returns diff_filepair so that the caller can
further add information to it, and the helper function diff_unmerge()
utilizes the feature itself, but does not expose it to its callers, which
was kind of selfish.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When reviewing a patch while concentrating primarily on the text after
then change, wading through pages of deleted text involves a cognitive
burden.
Introduce the -D option that omits the preimage text from the patch output
for deleted files. When used with -B (represent total rewrite as a single
wholesale deletion followed by a single wholesale addition), the preimage
text is also omitted.
To prevent such a patch from being applied by mistake, the output is
designed not to be usable by "git apply" (or GNU "patch"); it is strictly
for human consumption.
It of course is possible to "apply" such a patch by hand, as a human can
read the intention out of such a patch. It however is impossible to apply
such a patch even manually in reverse, as the whole point of this option
is to omit the information necessary to do so from the output.
Initial request by Mart Sõmermaa, documentation and tests helped by
Michael J Gruber.
Signed-off-by: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When there are too many paths in the project, the number of rename source
candidates "git diff -C -C" finds will exceed the rename detection limit,
and no inexact rename detection is performed. We however could fall back
to "git diff -C" if the number of modified paths is sufficiently small.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We might spend many seconds doing inexact rename detection
with no output. It's nice to let the user know that
something is actually happening.
This patch adds the infrastructure, but no callers actually
turn on progress reporting.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The warning is generated deep in the diffcore code, which
means that it will come first, followed possibly by a spew
of conflicts, making it hard to see.
Instead, let's have diffcore pass back the information about
how big the rename limit would needed to have been, and then
the caller can provide a more appropriate message (and at a
more appropriate time).
No refactoring of other non-merge callers is necessary,
because nobody else was even using the warn_on_rename_limit
feature.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The recursive merge strategy turns on rename detection but leaves the
rename threshold at the default. Add a strategy option to allow the user
to specify a rename threshold to use.
Signed-off-by: Kevin Ballard <kevin@sb.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Teach "-G<regexp>" that is similar to "-S<regexp> --pickaxe-regexp" to the
"git diff" family of commands. This limits the diff queue to filepairs
whose patch text actually has an added or a deleted line that matches the
given regexp. Unlike "-S<regexp>", changing other parts of the line that
has a substring that matches the given regexp IS counted as a change, as
such a change would appear as one deletion followed by one addition in a
patch text.
Unlike -S (pickaxe) that is intended to be used to quickly detect a commit
that changes the number of occurrences of hits between the preimage and
the postimage to serve as a part of larger toolchain, this is meant to be
used as the top-level Porcelain feature.
The implementation unfortunately has to run "diff" twice if you are
running "log" family of commands to produce patches in the final output
(e.g. "git log -p" or "git format-patch"). I think we _could_ cache the
result in-core if we wanted to, but that would require larger surgery to
the diffcore machinery (i.e. adding an extra pointer in the filepair
structure to keep a pointer to a strbuf around, stuff the textual diff to
the strbuf inside diffgrep_consume(), and make use of it in later stages
when it is available) and it may not be worth it.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* mm/shortopt-detached:
log: parse separate option for --glob
log: parse separate options like git log --grep foo
diff: parse separate options --stat-width n, --stat-name-width n
diff: split off a function for --stat-* option parsing
diff: parse separate options like -S foo
Conflicts:
revision.c
* jc/maint-follow-rename-fix:
log: test for regression introduced in v1.7.2-rc0~103^2~2
diff --follow: do call diffcore_std() as necessary
diff --follow: do not waste cycles while recursing
Usually, diff frontends populate the output queue with filepairs without
any rename information and call diffcore_std() to sort the renames out.
When --follow is in effect, however, diff-tree family of frontend has a
hack that looks like this:
diff-tree frontend
-> diff_tree_sha1()
. populate diff_queued_diff
. if --follow is in effect and there is only one change that
creates the target path, then
-> try_to_follow_renames()
-> diff_tree_sha1() with no pathspec but with -C
-> diffcore_std() to find renames
. if rename is found, tweak diff_queued_diff and put a
single filepair that records the found rename there
-> diffcore_std()
. tweak elements on diff_queued_diff by
- rename detection
- path ordering
- pickaxe filtering
We need to skip parts of the second call to diffcore_std() that is related
to rename detection, and do so only when try_to_follow_renames() did find
a rename. Earlier 1da6175 (Make diffcore_std only can run once before a
diff_flush, 2010-05-06) tried to deal with this issue incorrectly; it
unconditionally disabled any second call to diffcore_std().
This hopefully fixes the breakage.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The new "ignore" config option controls the default behavior for "git
status" and the diff family. It specifies under what circumstances they
consider submodules as modified and can be set separately for each
submodule.
The command line option "--ignore-submodules=" has been extended to accept
the new parameter "none" for both status and diff.
Users that chose submodules to get rid of long work tree scanning times
might want to set the "dirty" option for those submodules. This brings
back the pre 1.7.0 behavior, where submodule work trees were never
scanned for modifications. By using "--ignore-submodules=none" on the
command line the status and diff commands can be told to do a full scan.
This option can be set to the following values (which have the same name
and meaning as for the "--ignore-submodules" option of status and diff):
"all": All changes to the submodule will be ignored.
"dirty": Only differences of the commit recorded in the superproject and
the submodules HEAD will be considered modifications, all changes
to the work tree of the submodule will be ignored. When using this
value, the submodule will not be scanned for work tree changes at
all, leading to a performance benefit on large submodules.
"untracked": Only untracked files in the submodules work tree are ignored,
a changed HEAD and/or modified files in the submodule will mark it
as modified.
"none" (which is the default): Either untracked or modified files in a
submodules work tree or a difference between the subdmodules HEAD
and the commit recorded in the superproject will make it show up
as changed. This value is added as a new parameter for the
"--ignore-submodules" option of the diff family and "git status"
so the user can override the settings in the configuration.
Signed-off-by: Jens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change the option parsing logic in revision.c to accept separate forms
like `-S foo' in addition to `-Sfoo'. The rest of git already accepted
this form, but revision.c still used its own option parsing.
Short options affected are -S<string>, -l<num> and -O<orderfile>, for
which an empty string wouldn't make sense, hence -<option> <arg> isn't
ambiguous.
This patch does not handle --stat-name-width and --stat-width, which are
special-cases where diff_long_opt do not apply. They are handled in a
separate patch to ease review.
Original patch by Matthieu Moy, plus refactoring by Jonathan Nieder.
Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* gv/portable:
test-lib: use DIFF definition from GIT-BUILD-OPTIONS
build: propagate $DIFF to scripts
Makefile: Tru64 portability fix
Makefile: HP-UX 10.20 portability fixes
Makefile: HPUX11 portability fixes
Makefile: SunOS 5.6 portability fix
inline declaration does not work on AIX
Allow disabling "inline"
Some platforms lack socklen_t type
Make NO_{INET_NTOP,INET_PTON} configured independently
Makefile: some platforms do not have hstrerror anywhere
git-compat-util.h: some platforms with mmap() lack MAP_FAILED definition
test_cmp: do not use "diff -u" on platforms that lack one
fixup: do not unconditionally disable "diff -u"
tests: use "test_cmp", not "diff", when verifying the result
Do not use "diff" found on PATH while building and installing
enums: omit trailing comma for portability
Makefile: -lpthread may still be necessary when libc has only pthread stubs
Rewrite dynamic structure initializations to runtime assignment
Makefile: pass CPPFLAGS through to fllow customization
Conflicts:
Makefile
wt-status.h
The textconv functionality allows one to convert a file into text before
running diff. But this functionality can be useful to other features
such as blame.
Signed-off-by: Axel Bonnet <axel.bonnet@ensimag.imag.fr>
Signed-off-by: Clément Poulain <clement.poulain@ensimag.imag.fr>
Signed-off-by: Diane Gasselin <diane.gasselin@ensimag.imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The callback can be used to add some prefix string to each line of
diff output.
Signed-off-by: Bo Yang <struggleyb.nku@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Without this patch at least IBM VisualAge C 5.0 (I have 5.0.2) on AIX
5.1 fails to compile git.
enum style is inconsistent already, with some enums declared on one
line, some over 3 lines with the enum values all on the middle line,
sometimes with 1 enum value per line... and independently of that the
trailing comma is sometimes present and other times absent, often
mixing with/without trailing comma styles in a single file, and
sometimes in consecutive enum declarations.
Clearly, omitting the comma is the more portable style, and this patch
changes all enum declarations to use the portable omitted dangling
comma style consistently.
Signed-off-by: Gary V. Vaughan <gary@thewrittenword.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This teaches the --color-words engine a more general interface that
supports two new modes:
* --word-diff=plain, inspired by the 'wdiff' utility (most similar to
'wdiff -n <old> <new>'): uses delimiters [-removed-] and {+added+}
* --word-diff=porcelain, which generates an ad-hoc machine readable
format:
- each diff unit is prefixed by [-+ ] and terminated by newline as
in unified diff
- newlines in the input are output as a line consisting only of a
tilde '~'
Both of these formats still support color if it is enabled, using it
to highlight the differences. --color-words becomes a synonym for
--word-diff=color, which is the color-only format. Also adds some
compatibility/convenience options.
Thanks to Junio C Hamano and Miles Bader for good ideas.
Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since 1.7.0 submodules are considered dirty when they contain untracked
files. But when git status is called with the "-uno" option, the user
asked to ignore untracked files, so they must be ignored in submodules
too. To achieve this, the new flag DIFF_OPT_IGNORE_UNTRACKED_IN_SUBMODULES
is introduced.
Signed-off-by: Jens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since 1.7.0 there are three reasons a submodule is considered modified
against the work tree: It contains new commits, modified content or
untracked content. Lets show all reasons in the long format of git status,
so the user can better asses the nature of the modification. This change
does not affect the short and porcelain formats.
Two new members are added to "struct wt_status_change_data" to store the
information gathered by run_diff_files(). wt-status.c uses the new flag
DIFF_OPT_DIRTY_SUBMODULES to tell diff-lib.c it wants to get detailed
dirty information about submodules.
A hint line for submodules is printed in the dirty header when dirty
submodules are present.
Signed-off-by: Jens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* jc/fix-tree-walk:
read-tree --debug-unpack
unpack-trees.c: look ahead in the index
unpack-trees.c: prepare for looking ahead in the index
Aggressive three-way merge: fix D/F case
traverse_trees(): handle D/F conflict case sanely
more D/F conflict tests
tests: move convenience regexp to match object names to test-lib.sh
Conflicts:
builtin-read-tree.c
unpack-trees.c
unpack-trees.h
In the worst case is_submodule_modified() got called three times for
each submodule. The information we got from scanning the whole
submodule tree the first time can be reused instead.
New parameters have been added to diff_change() and diff_addremove(),
the information is stored in a new member of struct diff_filespec. Its
value is then reused instead of calling is_submodule_modified() again.
When no explicit "-dirty" is needed in the output the call to
is_submodule_modified() is not necessary when the submodules HEAD
already disagrees with the ref of the superproject, as this alone
marks it as modified. To achieve that, get_stat_data() got an extra
argument.
Signed-off-by: Jens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This makes the traversal of index be in sync with the tree traversal.
When unpack_callback() is fed a set of tree entries from trees, it
inspects the name of the entry and checks if the an index entry with
the same name could be hiding behind the current index entry, and
(1) if the name appears in the index as a leaf node, it is also
fed to the n_way_merge() callback function;
(2) if the name is a directory in the index, i.e. there are entries in
that are underneath it, then nothing is fed to the n_way_merge()
callback function;
(3) otherwise, if the name comes before the first eligible entry in the
index, the index entry is first unpacked alone.
When traverse_trees_recursive() descends into a subdirectory, the
cache_bottom pointer is moved to walk index entries within that directory.
All of these are omitted for diff-index, which does not even want to be
fed an index entry and a tree entry with D/F conflicts.
This fixes 3-way read-tree and exposes a bug in other parts of the system
in t6035, test #5. The test prepares these three trees:
O = HEAD^
100644 blob e69de29bb2 a/b-2/c/d
100644 blob e69de29bb2 a/b/c/d
100644 blob e69de29bb2 a/x
A = HEAD
100644 blob e69de29bb2 a/b-2/c/d
100644 blob e69de29bb2 a/b/c/d
100644 blob 587be6b4c3f93f93c489c0111bba5596147a26cb a/x
B = master
120000 blob a36b77384451ea1de7bd340ffca868249626bc52 a/b
100644 blob e69de29bb2 a/b-2/c/d
100644 blob e69de29bb2 a/x
With a clean index that matches HEAD, running
git read-tree -m -u --aggressive $O $A $B
now yields
120000 a36b77384451ea1de7bd340ffca868249626bc52 3 a/b
100644 e69de29bb2 0 a/b-2/c/d
100644 e69de29bb2 1 a/b/c/d
100644 e69de29bb2 2 a/b/c/d
100644 587be6b4c3f93f93c489c0111bba5596147a26cb 0 a/x
which is correct. "master" created "a/b" symlink that did not exist,
and removed "a/b/c/d" while HEAD did not do touch either path.
Before this series, read-tree did not notice the situation and resolved
addition of "a/b" and removal of "a/b/c/d" independently. If A = HEAD had
another path "a/b/c/e" added, this merge should conflict but instead it
silently resolved "a/b" and then immediately overwrote it to add
"a/b/c/e", which was quite bogus.
Tests in t1012 start to work with this.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* jc/1.7.0-diff-whitespace-only-status:
diff.c: fix typoes in comments
Make test case number unique
diff: Rename QUIET internal option to QUICK
diff: change semantics of "ignore whitespace" options
Conflicts:
diff.h
Inspired by the coloring of quilt.
Introduce a separate color and paint the hunk comment part, i.e. the name
of the function, in a separate color "diff.func" (defaults to plain).
Whitespace between hunk header and hunk comment is printed in plain color.
Signed-off-by: Bert Wesarg <bert.wesarg@googlemail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When you use the option --submodule=log you can see the submodule
summaries inlined in the diff, instead of not-quite-helpful SHA-1 pairs.
The format imitates what "git submodule summary" shows.
To do that, <path>/.git/objects/ is added to the alternate object
databases (if that directory exists).
This option was requested by Jens Lehmann at the GitTogether in Berlin.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Jens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The option "QUIET" primarily meant "find if we have _any_ difference as
quick as possible and report", which means we often do not even have to
look at blobs if we know the trees are different by looking at the higher
level (e.g. "diff-tree A B"). As a side effect, because there is no point
showing one change that we happened to have found first, it also enables
NO_OUTPUT and EXIT_WITH_STATUS options, making the end result look quiet.
Rename the internal option to QUICK to reflect this better; it also makes
grepping the source tree much easier, as there are other kinds of QUIET
option everywhere.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Traditionally, the --ignore-whitespace* options have merely meant to tell
the diff output routine that some class of differences are not worth
showing in the textual diff output, so that the end user has easier time
to review the remaining (presumably more meaningful) changes. These
options never affected the outcome of the command, given as the exit
status when the --exit-code option was in effect (either directly or
indirectly).
When you have only whitespace changes, however, you might expect
git diff -b --exit-code
to report that there is _no_ change with zero exit status.
Change the semantics of --ignore-whitespace* options to mean more than
"omit showing the difference in text".
The exit status, when --exit-code is in effect, is computed by checking if
we found any differences at the path level, while diff frontends feed
filepairs to the diffcore engine. When "ignore whitespace" options are in
effect, we defer this determination until the very end of diffcore
transformation. We simply do not know until the textual diff is
generated, which comes very late in the pipeline.
When --quiet is in effect, various diff frontends optimize by breaking out
early from the loop that enumerates the filepairs, when we find the first
path level difference; when --ignore-whitespace* is used the above change
automatically disables this optimization.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
index_is_dirty() in builtin-revert.c checks if the index is dirty.
This patch generalizes this function to check if the index differs
from a revision, i.e. the former index_is_dirty() behavior can now be
achieved by index_differs_from("HEAD", 0).
The second argument "diff_flags" allows to set further diff option
flags like DIFF_OPT_IGNORE_SUBMODULES. See DIFF_OPT_* macros in diff.h
for a list.
index_differs_from() seems to be useful for more than builtin-revert.c,
so it is moved into diff-lib.c and also used in builtin-commit.c.
Yet to mention:
- "rev.abbrev = 0;" can be safely removed.
This has no impact on performance or functioning of neither
setup_revisions() nor run_diff_index().
- rev.pending.objects is free()d because this fixes a leak.
(Also see 295dd2ad "Fix memory leak in traverse_commit_list")
Mentored-by: Daniel Barkalow <barkalow@iabervon.org>
Mentored-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Stephan Beyer <s-beyer@gmx.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In some applications, words are not delimited by white space. To
allow for that, you can specify a regular expression describing
what makes a word with
git diff --color-words='[A-Za-z0-9]+'
Note that words cannot contain newline characters.
As suggested by Thomas Rast, the words are the exact matches of the
regular expression.
Note that a regular expression beginning with a '^' will match only
a word at the beginning of the hunk, not a word at the beginning of
a line, and is probably not what you want.
This commit contains a quoting fix by Thomas Rast.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merge two hunks if there is only the specified number of otherwise unshown
context between them. For --inter-hunk-context=1, the resulting patch has
the same number of lines but shows uninterrupted context instead of a
context header line in between.
Patches generated with this option are easier to read but are also more
likely to conflict if the file to be patched contains other changes.
This patch keeps the default for this option at 0. It is intended to just
make the feature available in order to see its advantages and downsides.
Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Diffs that have been produced with textconv almost certainly
cannot be applied, so we want to be careful not to generate
them in things like format-patch.
This introduces a new diff options, ALLOW_TEXTCONV, which
controls this behavior. It is off by default, but is
explicitly turned on for the "log" family of commands, as
well as the "diff" porcelain (but not diff-* plumbing).
Because both text conversion and external diffing are
controlled by these diff options, we can get rid of the
"plumbing versus porcelain" distinction when reading the
config. This was an attempt to control the same thing, but
suffered from being too coarse-grained.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This new option --dirstat-by-file is the same as --dirstat, but it
counts "impacted files" instead of "impacted lines" (lines that are
added or removed).
Signed-off-by: Heikki Orsila <heikki.orsila@iki.fi>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The option used to be implemented as if it is a totally independent one,
but "git diff --cumulative" would not mean anything without "--dirstat".
This makes --cumulative imply --dirstat.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
With a new configuration "diff.mnemonicprefix", "git diff" shows the
differences between various combinations of preimage and postimage trees
with prefixes different from the standard "a/" and "b/". Hopefully this
will make the distinction stand out for some people.
"git diff" compares the (i)ndex and the (w)ork tree;
"git diff HEAD" compares a (c)ommit and the (w)ork tree;
"git diff --cached" compares a (c)ommit and the (i)ndex;
"git-diff HEAD:file1 file2" compares an (o)bject and a (w)ork tree entity;
"git diff --no-index a b" compares two non-git things (1) and (2).
Because these mnemonics now have meanings, they are swapped when reverse
diff is in effect and this feature is enabled.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If PATH_MAX on your system is smaller than a path stored, it may cause
buffer overflow and stack corruption in diff_addremove() and diff_change()
functions when running git-diff
Signed-off-by: Dmitry Potapov <dpotapov@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
