This fixes up a couple of minor issues with the real built-in
diff to be more usable:
- Omit ---/+++ header unless we emit diff output;
- Detect and punt binary diff like GNU does;
- Honor GIT_DIFF_OPTS minimally (only -u<number> and
--unified=<number> are currently supported);
- Omit line count of 1 from "@@ -l,k +m,n @@" hunk header
(i.e. when k == 1 or n == 1)
- Adjust testsuite for the lack of -p support.
Signed-off-by: Junio C Hamano <junkio@cox.net>
This uses a simplified libxdiff setup to generate unified diffs _without_
doing fork/execve of GNU "diff".
This has several huge advantages, for example:
Before:
[torvalds@g5 linux]$ time git diff v2.6.16.. > /dev/null
real 0m24.818s
user 0m13.332s
sys 0m8.664s
After:
[torvalds@g5 linux]$ time git diff v2.6.16.. > /dev/null
real 0m4.563s
user 0m2.944s
sys 0m1.580s
and the fact that this should be a lot more portable (ie we can ignore all
the issues with doing fork/execve under Windows).
Perhaps even more importantly, this allows us to do diffs without actually
ever writing out the git file contents to a temporary file (and without
any of the shell quoting issues on filenames etc etc).
NOTE! THIS PATCH DOES NOT DO THAT OPTIMIZATION YET! I was lazy, and the
current "diff-core" code actually will always write the temp-files,
because it used to be something that you simply had to do. So this current
one actually writes a temp-file like before, and then reads it into memory
again just to do the diff. Stupid.
But if this basic infrastructure is accepted, we can start switching over
diff-core to not write temp-files, which should speed things up even
further, especially when doing big tree-to-tree diffs.
Now, in the interest of full disclosure, I should also point out a few
downsides:
- the libxdiff algorithm is different, and I bet GNU diff has gotten a
lot more testing. And the thing is, generating a diff is not an exact
science - you can get two different diffs (and you will), and they can
both be perfectly valid. So it's not possible to "validate" the
libxdiff output by just comparing it against GNU diff.
- GNU diff does some nice eye-candy, like trying to figure out what the
last function was, and adding that information to the "@@ .." line.
libxdiff doesn't do that.
- The libxdiff thing has some known deficiencies. In particular, it gets
the "\No newline at end of file" case wrong. So this is currently for
the experimental branch only. I hope Davide will help fix it.
That said, I think the huge performance advantage, and the fact that it
integrates better is definitely worth it. But it should go into a
development branch at least due to the missing newline issue.
Technical note: this is based on libxdiff-0.17, but I did some surgery to
get rid of the extraneous fat - stuff that git doesn't need, and seriously
cutting down on mmfile_t, which had much more capabilities than the diff
algorithm either needed or used. In this version, "mmfile_t" is just a
trivial <pointer,length> tuple.
That said, I tried to keep the differences to simple removals, so that you
can do a diff between this and the libxdiff origin, and you'll basically
see just things getting deleted. Even the mmfile_t simplifications are
left in a state where the diffs should be readable.
Apologies to Davide, whom I'd love to get feedback on this all from (I
wrote my own "fill_mmfile()" for the new simpler mmfile_t format: the old
complex format had a helper function for that, but I did my surgery with
the goal in mind that eventually we _should_ just do
mmfile_t mf;
buf = read_sha1_file(sha1, type, &size);
mf->ptr = buf;
mf->size = size;
.. use "mf" directly ..
which was really a nightmare with the old "helpful" mmfile_t, and really
is that easy with the new cut-down interfaces).
[ Btw, as any hawk-eye can see from the diff, this was actually generated
with itself, so it is "self-hosting". That's about all the testing it
has gotten, along with the above kernel diff, which eye-balls correctly,
but shows the newline issue when you double-check it with "git-apply" ]
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
This changes diffcore-rename to reuse statistics information
gathered during similarity estimation, and updates the hashtable
implementation used to keep track of the statistics to be
denser. This seems to give better performance.
Signed-off-by: Junio C Hamano <junkio@cox.net>
Instead of depending of fork() and execve() and doing things in between
the two, make the git diff functions do everything up front, and then do
a single "spawn_prog()" invocation to run the actual external diff
program (if any is even needed).
This actually ends up simplifying the code, and should make it much
easier to make it efficient under broken operating systems (read: Windows).
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
Earlier it did not grok the 0{40} SHA1 very well, but what it
needed to do was to find the shortest 0{N} that is not used as a
valid object name to be consistent with the way names of valid
objects are abbreviated. This makes some users simpler.
Signed-off-by: Junio C Hamano <junkio@cox.net>
This adds "assume unchanged" logic, started by this message in the list
discussion recently:
<Pine.LNX.4.64.0601311807470.7301@g5.osdl.org>
This is a workaround for filesystems that do not have lstat()
that is quick enough for the index mechanism to take advantage
of. On the paths marked as "assumed to be unchanged", the user
needs to explicitly use update-index to register the object name
to be in the next commit.
You can use two new options to update-index to set and reset the
CE_VALID bit:
git-update-index --assume-unchanged path...
git-update-index --no-assume-unchanged path...
These forms manipulate only the CE_VALID bit; it does not change
the object name recorded in the index file. Nor they add a new
entry to the index.
When the configuration variable "core.ignorestat = true" is set,
the index entries are marked with CE_VALID bit automatically
after:
- update-index to explicitly register the current object name to the
index file.
- when update-index --refresh finds the path to be up-to-date.
- when tools like read-tree -u and apply --index update the working
tree file and register the current object name to the index file.
The flag is dropped upon read-tree that does not check out the index
entry. This happens regardless of the core.ignorestat settings.
Index entries marked with CE_VALID bit are assumed to be
unchanged most of the time. However, there are cases that
CE_VALID bit is ignored for the sake of safety and usability:
- while "git-read-tree -m" or git-apply need to make sure
that the paths involved in the merge do not have local
modifications. This sacrifices performance for safety.
- when git-checkout-index -f -q -u -a tries to see if it needs
to checkout the paths. Otherwise you can never check
anything out ;-).
- when git-update-index --really-refresh (a new flag) tries to
see if the index entry is up to date. You can start with
everything marked as CE_VALID and run this once to drop
CE_VALID bit for paths that are modified.
Most notably, "update-index --refresh" honours CE_VALID and does
not actively stat, so after you modified a file in the working
tree, update-index --refresh would not notice until you tell the
index about it with "git-update-index path" or "git-update-index
--no-assume-unchanged path".
This version is not expected to be perfect. I think diff
between index and/or tree and working files may need some
adjustment, and there probably needs other cases we should
automatically unmark paths that are marked to be CE_VALID.
But the basics seem to work, and ready to be tested by people
who asked for this feature.
Signed-off-by: Junio C Hamano <junkio@cox.net>
So far, e.g. git-update-index --refresh was basically uninterruptable
by ctrl-c, since it hooked the SIGINT handler, but that handler would
only unlink the lockfile but not actually quit. This makes it propagate
the signal to the default handler.
Note that I expected it to work without resetting the signal handler to
SIG_DFL, but without that it ended in an infinite loop of tgkill()s -
is my glibc violating SUS or what?
Signed-off-by: Petr Baudis <pasky@suse.cz>
Signed-off-by: Junio C Hamano <junkio@cox.net>
Earier specifying an abbreviation shorter than minimum fell back
to full 40 letters, which was nonsense. Make it to fall back to
the minimum number (currently 4).
Signed-off-by: Junio C Hamano <junkio@cox.net>
The minimum length of abbreviated object name was hardcoded in
different places to be 4, risking inconsistencies in the future.
Also there were three different "default abbreviation
precision". Use two C preprocessor symbols to clean up this
mess.
Signed-off-by: Junio C Hamano <junkio@cox.net>
This patch converts a stat() to an lstat() call, thereby fixing the case
when the date of a symlink was not the same as the one recorded in the
index. The included test case demonstrates this.
This is for the case that the symlink points to a non-existing file. If
the file exists, worse things than just an error message happen.
Signed-off-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Junio C Hamano <junkio@cox.net>
Avoid asking for zero bytes when that change simplifies overall
logic. Later we would change the wrapper to ask for 1 byte on
platforms that return NULL for zero byte request.
Signed-off-by: Junio C Hamano <junkio@cox.net>
When I show transcripts to explain how something works, I often
find myself hand-editing the diff-raw output to shorten various
object names in the output.
This adds --abbrev option to the diff family, which shortens
diff-raw output and diff-tree commit id headers.
Signed-off-by: Junio C Hamano <junkio@cox.net>
Otherwise we would end up linking all the unneeded stuff into git-daemon
only to link with git_default_config.
Signed-off-by: Junio C Hamano <junkio@cox.net>
Better variant, which handles stuff like "4.5%" and rejects
"192.168.0.1". Additionally, make sure numbers are unsigned (I'm making
them unsigned long just for the hell of it), to make sure that
artificial wraparound scenarios don't cause harm.
-hpa
[jc: with this, -M100 changes its meaning back to 10%. People
wanting to say "pure renames only" should now say -M100% or
-M1.0; sounds a bit like an earthquake, but arguably things are
more consistent this way ;-)]
Signed-off-by: Junio C Hamano <junkio@cox.net>
When the user is interested in pure renames, there is no point
doing the similarity scores. This changes the score argument
parsing to special case -M100 (otherwise, it is a precision
scaled value 0 <= v < 1 and would mean 0.1, not 1.0 --- if you
do mean 0.1, you can say -M1), and optimizes the diffcore_rename
transformation to only look at pure renames in that case.
Signed-off-by: Junio C Hamano <junkio@cox.net>
A new option, --full-index, is introduced to diff family. This
causes the full object name of pre- and post-images to appear on
the index line of patch formatted output, to be used in
conjunction with --allow-binary-replacement option of git-apply.
Signed-off-by: Junio C Hamano <junkio@cox.net>
A while ago, a rename-detection limit logic was implemented as a
response to this thread:
http://marc.theaimsgroup.com/?l=git&m=112413080630175
where gitweb was found to be using a lot of time and memory to
detect renames on huge commits. git-diff family takes -l<num>
flag, and if the number of paths that are rename destination
candidates (i.e. new paths with -M, or modified paths with -C)
are larger than that number, skips rename/copy detection even
when -M or -C is specified on the command line.
This commit makes the rename detection limit easier to use. You
can have:
[diff]
renamelimit = 30
in your .git/config file to specify the default rename detection
limit. You can override this from the command line; giving 0
means 'unlimited':
git diff -M -l0
We might want to change the default behaviour, when you do not
have the configuration, to limit it to say 20 paths or so. This
would also help the diffstat generation after a big 'git pull'.
Signed-off-by: Junio C Hamano <junkio@cox.net>
This makes the tree diff functionality independent of the "git-diff-tree"
program, by splitting the core functionality up into a library file.
This will be needed for when we teach git-rev-list to only follow a
specified set of pathnames, rather than the global revision history.
Most of it is a fairly straightforward code move, but it also involves
some calling convention cleanup, and moving some of the static variables
from diff-tree.c into the options structure.
The actual tree change callback routines also become paramterized by the
diff_options structure, allowing the library functionality to do something
else than just show the diff on stdout.
Right now the only user of this functionality remains git-diff-tree
itself.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
This fixes the default built-in exec() of "diff" to add a "--" before the
filenames, so that if a filename starts with a "-", the diff program won't
think it's an option.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
This adds more cruft to diff --git header to record the blob SHA1 and
the mode the patch/diff is intended to be applied against, to help the
receiving end fall back on a three-way merge. The new header looks
like this:
diff --git a/apply.c b/apply.c
index 7be5041..8366082 100644
--- a/apply.c
+++ b/apply.c
@@ -14,6 +14,7 @@
// files that are being modified, but doesn't apply the patch
// --stat does just a diffstat, and doesn't actually apply
+// --show-index-info shows the old and new index info for...
...
Upon receiving such a patch, if the patch did not apply cleanly to the
target tree, the recipient can try to find the matching old objects in
her object database and create a temporary tree, apply the patch to
that temporary tree, and attempt a 3-way merge between the patched
temporary tree and the target tree using the original temporary tree
as the common ancestor.
The patch lifts the code to compute the hash for an on-filesystem
object from update-index.c and makes it available to the diff output
routine.
Signed-off-by: Junio C Hamano <junkio@cox.net>
When many paths are modified, rename detection takes a lot of time.
The new option -l<num> can be used to disable rename detection when
more than <num> paths are possibly created as renames.
Signed-off-by: Junio C Hamano <junkio@cox.net>
This is a long overdue clean-up to the code for parsing and passing
diff options. It also tightens some constness issues.
Signed-off-by: Junio C Hamano <junkio@cox.net>
The textual diff generation with built-in '-p' in diff-* brothers has
proven to be useful enough that git-diff-helper outlived its usefulness.
Signed-off-by: Junio C Hamano <junkio@cox.net>
It is a bit embarrassing that it took this long for a fix since the
problem was first reported on Aug 13th.
Message-ID: <87y876gl1r.wl@mail2.atmark-techno.com>
From: Yasushi SHOJI <yashi@atmark-techno.com>
Newsgroups: gmane.comp.version-control.git
Subject: [patch] possible memory leak in diff.c::diff_free_filepair()
Date: Sat, 13 Aug 2005 19:58:56 +0900
This time I used valgrind to make sure that it does not overeagerly
discard memory that is still being used.
Signed-off-by: Junio C Hamano <junkio@cox.net>
This simplifies and fixes the initialization of a "diff_filespec" when
allocated.
The old code would not initialize "sha1_valid". Noticed by valgrind.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
When (A,B) ==> (B,C) rename-copy was detected, we incorrectly said
that C was created by copying B. This is because we only check if the
path of rename/copy source still exists in the resulting tree to see
if the file is renamed out of existence. In this case, the new B is
created by copying or renaming A, so the original B is lost and we
should say C is a rename of B not a copy of B.
Signed-off-by: Junio C Hamano <junkio@cox.net>
We have deprecated the old environment variable names for quite a
while and now it's time to remove them. Gone are:
SHA1_FILE_DIRECTORIES AUTHOR_DATE AUTHOR_EMAIL AUTHOR_NAME
COMMIT_AUTHOR_EMAIL COMMIT_AUTHOR_NAME SHA1_FILE_DIRECTORY
Signed-off-by: Junio C Hamano <junkio@cox.net>
Omitting the first branch in ?: is a GNU extension. Cute,
but not supported by other compilers. Replaced mostly
by explicit tests. Calls to getenv() simply are repeated
on non-GNU compilers.
Signed-off-by: Jason Riedy <ejr@cs.berkeley.edu>
When I run git-diff-tree on big change, it seems the command eats so
much memory. so I just put git under valgrind to see what's going on.
diff_free_filespec_data() doesn't free diff_filespec itself.
[jc: I ended up doing things slightly differently from Yasushi's
patch. The original idea was to use free_filespec_data() only to
free the data portion and keep useing the filespec itself, but
no existing code seems to do things that way, so I just yanked
that part out.]
Signed-off-by: Yasushi SHOJI <yashi@atmark-techno.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>
Inspired by patch from Timo Sirainen. Most of them are not
strictly necessary but making warnings less chatty would help
spot real bugs later.
Signed-off-by: Junio C Hamano <junkio@cox.net>
I have reviewed all occurrences of mmap() in git and fixed three types
of errors/defects:
1) The result is not checked.
2) The file descriptor is closed if mmap() succeeds, but not when it
fails.
3) Various casts applied to -1 are used instead of MAP_FAILED, which is
specifically defined to check mmap() return value.
[jc: This is a second round of Pavel's patch. He fixed up the problem
that close() potentially clobbering the errno from mmap, which
the first round had.]
Signed-off-by: Pavel Roskin <proski@gnu.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
Both Cogito and StGIT prefer to see 'A' for new files. The
current 'N' is visually harder to distinguish from 'M', which is
used for modified files. Prepare the internals to use symbolic
constants to make the change easier.
Signed-off-by: Junio C Hamano <junkio@cox.net>
This removes the separate "formats" for name and name-with-zero-
termination.
It also removes the difference between HUMAN and MACHINE formats, and
they both become DIFF_FORMAT_RAW, with the difference being just in the
line and inter-filename termination.
It also makes the code easier to understand.
Porcelain layers often want to find only names of changed files,
and even with diff-raw output format they end up having to pick
out only the filename. Support --name-only (and --name-only-z
for xargs -0 and cpio -0 users that want to treat filenames with
embedded newlines sanely) flag to help them.
Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
A useful shell safety helper sq_expand() was hidden as a static
function in diff.c. Extract it out and make it available as
sq_quote().
Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This lets us eliminate one use of map_sha1_file() outside
sha1_file.c, to bring us one step closer to the packed GIT.
Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Patch for a completely rewritten file detected by the -B flag
was shown as a pair of creation followed by deletion in earlier
versions. This was an misguided attempt to make reviewing such
a complete rewrite easier, and unnecessarily ended up confusing
git-apply. Instead, show the entire contents of old version
prefixed with '-', followed by the entire contents of new
version prefixed with '+'. This gives the same easy-to-review
for human consumer while keeping it a single, regular
modification patch for machine consumption, something that even
GNU patch can grok.
Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This is a halfway between debugging aid and a helper to write an
ultra-smart merge scripts. The new option takes a string that
consists of a list of "status" letters, and limits the diff
output to only those classes of changes, with two exceptions:
- A broken pair (aka "complete rewrite"), does not match D
(deleted) or N (created). Use B to look for them.
- The letter "A" in the diff-filter string does not match
anything itself, but causes the entire diff that contains
selected patches to be output (this behaviour is similar to
that of --pickaxe-all for the -S option).
For example,
$ git-rev-list HEAD |
git-diff-tree --stdin -s -v -B -C --diff-filter=BCR
shows a list of commits that have complete rewrite, copy, or
rename.
Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When rename/copy uses a file that was broken by diffcore-break
as the source, and the broken filepair gets merged back later,
the output was mislabeled as a rename. In this case, the source
file ends up staying in the output, so we should label it as a
copy instead.
Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When an unmerged path was fed via diff_unmerged() into diffcore,
it eventually called run_diff() with "one" and "two" parameters
with NULL, but run_diff() was not written carefully enough to
notice this situation.
Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Junio C Hamano