Commit Graph

44 Commits

Author SHA1 Message Date
Ramkumar Ramachandra
276b22d333 diffcore-pickaxe: make error messages more consistent
Currently, diffcore-pickaxe reports two distinct errors for the same
user error:

    $ git log --pickaxe-regex -S'\1'
    fatal: invalid pickaxe regex: Invalid back reference

    $ git log -G'\1'
    fatal: invalid log-grep regex: Invalid back reference

This "log-grep" was only an internal name for the -G feature during
development, and invite confusion with "git log --grep=<pattern>".

Change the error messages to say "invalid regex".

Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-06-03 10:50:22 -07:00
Jeff King
61690bf4a1 diffcore-pickaxe: unify code for log -S/-G
The logic flow of has_changes() used for "log -S" and diff_grep()
used for "log -G" are essentially the same.  See if we have both
sides that could be different in any interesting way, slurp the
contents in core, possibly after applying textconv, inspect the
contents, clean-up and report the result.  The only difference
between the two is how "inspect" step works.

Unify this codeflow in a helper, pickaxe_match(), which takes a
callback function that implements the specific "inspect" step.

After removing the common scaffolding code from the existing
has_changes() and diff_grep(), they each becomes such a callback
function suitable for passing to pickaxe_match().

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-04-05 10:31:09 -07:00
Junio C Hamano
88ff684dd5 diffcore-pickaxe: fix leaks in "log -S<block>" and "log -G<pattern>"
The diff_grep() and has_changes() functions had early return
codepaths for unmerged filepairs, which simply returned 0.  When we
taught textconv filter to them, one was ignored and continued to
return early without freeing the result filtered by textconv, and
the other had a failed attempt to fix, which allowed the planned
return value 0 to be overwritten by a bogus call to contains().

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-04-05 10:31:09 -07:00
Junio C Hamano
ebb7226258 diffcore-pickaxe: port optimization from has_changes() to diff_grep()
These two functions are called in the same codeflow to implement
"log -S<block>" and "log -G<pattern>", respectively, but the latter
lacked two obvious optimizations the former implemented, namely:

 - When a pickaxe limit is not given at all, they should return
   without wasting any cycle;

 - When both sides of the filepair are the same, and the same
   textconv conversion apply to them, return early, as there will be
   no interesting differences between the two anyway.

Also release the filespec data once the processing is done (this is
not about leaking memory--it is about releasing data we finished
looking at as early as possible).

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-04-05 10:31:09 -07:00
Simon Ruderich
a8f6109428 diffcore-pickaxe: respect --no-textconv
git log -S doesn't respect --no-textconv:

    $ echo '*.txt diff=wrong' > .gitattributes
    $ git -c diff.wrong.textconv='xxx' log --no-textconv -Sfoo
    error: cannot run xxx: No such file or directory
    fatal: unable to read files to diff

Reported-by: Matthieu Moy <Matthieu.Moy@grenoble-inp.fr>
Signed-off-by: Simon Ruderich <simon@ruderich.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-04-05 10:30:44 -07:00
Jeff King
7cdb9b42c3 diffcore-pickaxe: remove fill_one()
fill_one is _almost_ identical to just calling fill_textconv; the
exception is that for the !DIFF_FILE_VALID case, fill_textconv gives us
an empty buffer rather than a NULL one. Since we currently use the NULL
pointer as a signal that the file is not present on one side of the
diff, we must now switch to using DIFF_FILE_VALID to make the same
check.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Simon Ruderich <simon@ruderich.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-04-04 20:33:19 -07:00
Simon Ruderich
bc6158981b diffcore-pickaxe: remove unnecessary call to get_textconv()
The fill_one() function is responsible for finding and filling the
textconv filter as necessary, and is called by diff_grep() function
that implements "git log -G<pattern>".

The has_changes() function that implements "git log -S<block>" calls
get_textconv() for two sides being compared, before it checks to see
if it was asked to perform the pickaxe limiting.  Move the code
around to avoid this wastage.

After has_changes() calls get_textconv() to obtain textconv for both
sides, fill_one() is called to use them.

By adding get_textconv() to diff_grep() and relieving fill_one() of
responsibility to find the textconv filter, we can avoid calling
get_textconv() twice in has_changes().

With this change it's also no longer necessary for fill_one() to
modify the textconv argument, therefore pass a pointer instead of a
pointer to a pointer.

Signed-off-by: Simon Ruderich <simon@ruderich.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-04-04 20:33:19 -07:00
Jeff King
ef90ab66e8 pickaxe: use textconv for -S counting
We currently just look at raw blob data when using "-S" to
pickaxe. This is mostly historical, as pickaxe predates the
textconv feature. If the user has bothered to define a
textconv filter, it is more likely that their search string will be
on the textconv output, as that is what they will see in the
diff (and we do not even provide a mechanism for them to
search for binary needles that contain NUL characters).

This patch teaches "-S" to use textconv, just as we
already do for "-G".

Signed-off-by: Jeff King <peff@peff.net>
2012-10-28 08:48:17 -04:00
Jeff King
8fa4b09fb1 pickaxe: hoist empty needle check
If we are given an empty pickaxe needle like "git log -S ''",
it is impossible for us to find anything (because no matter
what the content, the count will always be 0). We currently
check this at the lowest level of contains(). Let's hoist
the logic much earlier to has_changes(), so that it is
simpler to return our answer before loading any blob data.

Signed-off-by: Jeff King <peff@peff.net>
2012-10-28 08:48:09 -04:00
Jeff King
b1c2f57db3 diff_grep: use textconv buffers for add/deleted files
If you use "-G" to grep a diff, we will apply a configured
textconv filter to the data before generating the diff.
However, if the diff is an addition or deletion, we do not
bother running the diff at all, and just look for the token
in the added (or removed) content. This works because we
know that the diff must contain every line of content.

However, while we used the textconv-derived buffers in the
regular diff, we accidentally passed the original unmodified
buffers to regexec when checking the added or removed
content. This could lead to an incorrect answer.

Worse, in some cases we might have a textconv buffer but no
original buffer (e.g., if we pulled the textconv data from
cache, or if we reused a working tree file when generating
it). In that case, we could actually feed NULL to regexec
and segfault.

Reported-by: Peter Oberndorfer <kumbayo84@arcor.de>
Signed-off-by: Jeff King <peff@peff.net>
2012-10-28 07:59:44 -04:00
Junio C Hamano
accccde483 pickaxe: allow -i to search in patch case-insensitively
"git log -S<string>" is a useful way to find the last commit in the
codebase that touched the <string>. As it was designed to be used by a
porcelain script to dig the history starting from a block of text that
appear in the starting commit, it never had to look for anything but an
exact match.

When used by an end user who wants to look for the last commit that
removed a string (e.g. name of a variable) that he vaguely remembers,
however, it is useful to support case insensitive match.

When given the "--regexp-ignore-case" (or "-i") option, which originally
was designed to affect case sensitivity of the search done in the commit
log part, e.g. "log --grep", the matches made with -S/-G pickaxe search is
done case insensitively now.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-02-28 16:15:29 -08:00
René Scharfe
8a94151d61 pickaxe: factor out pickaxe
Move the duplicate diff queue loop into its own function that accepts
a match function: has_changes() for -S and diff_grep() for -G.

Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-10-07 15:46:14 -07:00
René Scharfe
db99cb7000 pickaxe: give diff_grep the same signature as has_changes
Change diff_grep() to match the signature of has_changes() as a
preparation for the next patch that will use function pointers to
the two.

Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-10-07 15:46:14 -07:00
René Scharfe
5d176fb6b6 pickaxe: pass diff_options to contains and has_changes
Remove the unused parameter needle from contains() and has_changes().

Also replace the parameter len with a pointer to the diff_options.  We
can use its member pickaxe to check if the needle is an empty string
and use the kwsmatch structure to find out the length of the match
instead.

This change is done as a preparation to unify the signatures of
has_changes() and diff_grep(), which will be used in the patch after
the next one to factor out common code.

Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-10-07 15:46:13 -07:00
René Scharfe
15dafaf80d pickaxe: factor out has_changes
Move duplicate if/else construct into its own helper function.

Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-10-07 15:46:13 -07:00
René Scharfe
8e854b00d8 pickaxe: plug regex/kws leak
With -S... --pickaxe-all, free the regex or the kws before returning
even if we found a match.  Also get rid of the variable has_changes,
as we can simply break out of the loop.

Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-10-07 15:46:13 -07:00
René Scharfe
2b5f07f16c pickaxe: plug regex leak
With -G... --pickaxe-all, free the regex before returning even if we
found a match.  Also get rid of the variable has_changes, as we can
simply break out of the loop.

Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-10-07 15:46:13 -07:00
René Scharfe
05ac978495 pickaxe: plug diff filespec leak with empty needle
Check first for the unlikely case of an empty needle string and only
then populate the filespec, lest we leak it.

Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-10-07 15:46:12 -07:00
Fredrik Kuivinen
b95c5ada99 Use kwset in pickaxe
Benchmarks in the hot cache case:

before:
$ perf stat --repeat=5 git log -Sqwerty

Performance counter stats for 'git log -Sqwerty' (5 runs):

       47,092,744 cache-misses             #      2.825 M/sec   ( +-   1.607% )
      123,368,389 cache-references         #      7.400 M/sec   ( +-   0.812% )
      330,040,998 branch-misses            #      3.134 %       ( +-   0.257% )
   10,530,896,750 branches                 #    631.663 M/sec   ( +-   0.121% )
   62,037,201,030 instructions             #      1.399 IPC     ( +-   0.142% )
   44,331,294,321 cycles                   #   2659.073 M/sec   ( +-   0.326% )
           96,794 page-faults              #      0.006 M/sec   ( +-  11.952% )
               25 CPU-migrations           #      0.000 M/sec   ( +-  25.266% )
            1,424 context-switches         #      0.000 M/sec   ( +-   0.540% )
     16671.708650 task-clock-msecs         #      0.997 CPUs    ( +-   0.343% )

      16.728692052  seconds time elapsed   ( +-   0.344% )

after:
$ perf stat --repeat=5 git log -Sqwerty

Performance counter stats for 'git log -Sqwerty' (5 runs):

       51,385,522 cache-misses             #      4.619 M/sec   ( +-   0.565% )
      129,177,880 cache-references         #     11.611 M/sec   ( +-   0.219% )
      319,222,775 branch-misses            #      6.946 %       ( +-   0.134% )
    4,595,913,233 branches                 #    413.086 M/sec   ( +-   0.112% )
   31,395,042,533 instructions             #      1.062 IPC     ( +-   0.129% )
   29,558,348,598 cycles                   #   2656.740 M/sec   ( +-   0.204% )
           93,224 page-faults              #      0.008 M/sec   ( +-   4.487% )
               19 CPU-migrations           #      0.000 M/sec   ( +-  10.425% )
              950 context-switches         #      0.000 M/sec   ( +-   0.360% )
     11125.796039 task-clock-msecs         #      0.997 CPUs    ( +-   0.239% )

      11.164216599  seconds time elapsed   ( +-   0.240% )

So the kwset code is about 33% faster.

Signed-off-by: Fredrik Kuivinen <frekui@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-08-20 22:33:57 -07:00
Brandon Casey
8520913cc5 diffcore-pickaxe.c: a void function shouldn't try to return something
Signed-off-by: Brandon Casey <casey@nrlssc.navy.mil>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-10-06 13:45:18 -07:00
Junio C Hamano
90215bf300 Merge branch 'maint'
* maint:
  Documentation/git-clone: describe --mirror more verbosely
  do not depend on signed integer overflow
  work around buggy S_ISxxx(m) implementations
  xdiff: cast arguments for ctype functions to unsigned char
  init: plug tiny one-time memory leak
  diffcore-pickaxe.c: remove unnecessary curly braces
  t3020 (ls-files-error-unmatch): remove stray '1' from end of file
  setup: make sure git dir path is in a permanent buffer
  environment.c: remove unused variable
  git-svn: fix processing of decorated commit hashes
  git-svn: check_cherry_pick should exclude commits already in our history
  Documentation/git-svn: discourage "noMetadata"
2010-10-06 12:10:02 -07:00
Brandon Casey
95ae69b95b diffcore-pickaxe.c: remove unnecessary curly braces
Signed-off-by: Brandon Casey <casey@nrlssc.navy.mil>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-10-05 08:41:58 -07:00
Junio C Hamano
f506b8e8b5 git log/diff: add -G<regexp> that greps in the patch text
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>
2010-08-31 14:30:29 -07:00
Junio C Hamano
382f013bc4 diff: pass the entire diff-options to diffcore_pickaxe()
That would make it easier to give enhanced feature to the
pickaxe transformation.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-08-31 14:30:28 -07:00
Bo Yang
9ca5df9061 Add a macro DIFF_QUEUE_CLEAR.
Refactor the diff_queue_struct code, this macro help
to reset the structure.

Signed-off-by: Bo Yang <struggleyb.nku@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-05-07 09:34:27 -07:00
René Scharfe
50fd6997c6 pickaxe: count regex matches only once
When --pickaxe-regex is used, forward past the end of matches instead of
advancing to the byte after their start.  This way matches count only
once, even if the regular expression matches their tail -- like in the
fixed-string fork of the code.

E.g.: /.*/ used to count the number of bytes instead of the number of
lines.  /aa/ resulted in a count of two in "aaa" instead of one.

Also document the fact that regexec() needs a NUL-terminated string as
its second argument by adding an assert().

Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-03-17 15:10:12 -07:00
René Scharfe
ce163c793d diffcore-pickaxe: use memmem()
Use memmem() instead of open-coding it.  The system libraries usually have a
much faster version than the memcmp()-loop here.  Even our own fall-back in
compat/, which is used on Windows, is slightly faster.

The following commands were run in a Linux kernel repository and timed, the
best of five results is shown:

  $ STRING='Ensure that the real time constraints are schedulable.'
  $ git log -S"$STRING" HEAD -- kernel/sched.c >/dev/null

On Ubuntu 8.10 x64, before (v1.6.2-rc2):

  8.09user 0.04system 0:08.14elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k
  0inputs+0outputs (0major+30952minor)pagefaults 0swaps

And with the patch:

  1.50user 0.04system 0:01.54elapsed 100%CPU (0avgtext+0avgdata 0maxresident)k
  0inputs+0outputs (0major+30645minor)pagefaults 0swaps

On Fedora 10 x64, before:

  8.34user 0.05system 0:08.39elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k
  0inputs+0outputs (0major+29268minor)pagefaults 0swaps

And with the patch:

  1.15user 0.05system 0:01.20elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k
  0inputs+0outputs (0major+32253minor)pagefaults 0swaps

On Windows Vista x64, before:

  real    0m9.204s
  user    0m0.000s
  sys     0m0.000s

And with the patch:

  real    0m8.470s
  user    0m0.000s
  sys     0m0.000s

Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-03-02 18:28:03 -08:00
Junio C Hamano
a6080a0a44 War on whitespace
This uses "git-apply --whitespace=strip" to fix whitespace errors that have
crept in to our source files over time.  There are a few files that need
to have trailing whitespaces (most notably, test vectors).  The results
still passes the test, and build result in Documentation/ area is unchanged.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-06-07 00:04:01 -07:00
Junio C Hamano
a0cb94006c diff -S: release the image after looking for needle in it
Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-05-07 15:54:32 -07:00
Jeff King
e1b161161d diffcore-pickaxe: fix infinite loop on zero-length needle
The "contains" algorithm runs into an infinite loop if the needle string
has zero length. The loop could be modified to handle this, but it makes
more sense to simply have an empty needle return no matches. Thus, a
command like
  git log -S
produces no output.

We place the check at the top of the function so that we get the same
results with or without --pickaxe-regex. Note that until now,
  git log -S --pickaxe-regex
would match everything, not nothing.

Arguably, an empty pickaxe string should simply produce an error
message; however, this is still a useful assertion to add to the
algorithm at this layer of the code.

Noticed by Bill Lear.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-01-25 21:17:19 -08:00
Junio C Hamano
85023577a8 simplify inclusion of system header files.
This is a mechanical clean-up of the way *.c files include
system header files.

 (1) sources under compat/, platform sha-1 implementations, and
     xdelta code are exempt from the following rules;

 (2) the first #include must be "git-compat-util.h" or one of
     our own header file that includes it first (e.g. config.h,
     builtin.h, pkt-line.h);

 (3) system headers that are included in "git-compat-util.h"
     need not be included in individual C source files.

 (4) "git-compat-util.h" does not have to include subsystem
     specific header files (e.g. expat.h).

Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-12-20 09:51:35 -08:00
Johannes Schindelin
46b8dec038 On some platforms, certain headers need to be included before regex.h
Happily, these are already included in cache.h, which is included anyway...
so: change the order of includes.

Signed-off-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-04-04 17:14:06 -07:00
Petr Baudis
d01d8c6782 Support for pickaxe matching regular expressions
git-diff-* --pickaxe-regex will change the -S pickaxe to match
POSIX extended regular expressions instead of fixed strings.

The regex.h library is a rather stupid interface and I like pcre too, but
with any luck it will be everywhere we will want to run Git on, it being
POSIX.2 and all. I'm not sure if we can expect platforms like AIX to
conform to POSIX.2 or if win32 has regex.h. We might add a flag to
Makefile if there is a portability trouble potential.

Signed-off-by: Petr Baudis <pasky@suse.cz>
2006-04-04 13:44:15 -07:00
Junio C Hamano
2002eed6c9 [PATCH] diffcore-pickaxe: switch to "counting" behaviour.
Instead of finding old/new pair that one side has and the
other side does not have the specified string, find old/new pair
that contains the specified string as a substring different
number of times.  This would still not catch a case where you
introduce two static variable declarations and remove two static
function definitions from a file with -S"static", but would make
it behave a bit more intuitively.

Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-23 20:27:49 -07:00
Junio C Hamano
844e6e4d58 [PATCH] Do not include unused header files.
Some source files were including "delta.h" without actually
needing it.  Remove them.

Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-29 11:42:29 -07:00
Junio C Hamano
f0c6b2a2fd [PATCH] Optimize diff-tree -[CM] --stdin
This attempts to optimize "diff-tree -[CM] --stdin", which
compares successible tree pairs.  This optimization does not
make much sense for other commands in the diff-* brothers.

When reading from --stdin and using rename/copy detection, the
patch makes diff-tree to read the current index file first.
This is done to reuse the optimization used by diff-cache in the
non-cached case.  Similarity estimator can avoid expanding a
blob if the index says what is in the work tree has an exact
copy of that blob already expanded.

Another optimization the patch makes is to check only file sizes
first to terminate similarity estimation early.  In order for
this to work, it needs a way to tell the size of the blob
without expanding it.  Since an obvious way of doing it, which
is to keep all the blobs previously used in the memory, is too
costly, it does so by keeping the filesize for each object it
has already seen in memory.

Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-29 11:17:44 -07:00
Junio C Hamano
367cec1c02 [PATCH] Add --pickaxe-all to diff-* brothers.
When --pickaxe-all is given in addition to -S, pickaxe shows the
entire diffs contained in the changeset, not just the diffs for
the filepair that touched the sought-after string.  This is
useful to see the changes in context.

Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-29 11:17:43 -07:00
Junio C Hamano
226406f693 [PATCH] Introduce diff_free_filepair() funcion.
This introduces a new function to free a common data structure,
and plugs some leaks.

Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-29 11:17:43 -07:00
Junio C Hamano
046aa6440f [PATCH] Performance fix for pickaxe.
The pickaxe was expanding the blobs and searching in them even
when it should have already known that both sides are the same.

Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-23 11:49:30 -07:00
Junio C Hamano
f7c1512af8 [PATCH] Rename/copy detection fix.
The rename/copy detection logic in earlier round was only good
enough to show patch output and discussion on the mailing list
about the diff-raw format updates revealed many problems with
it.  This patch fixes all the ones known to me, without making
things I want to do later impossible, mostly related to patch
reordering.

 (1) Earlier rename/copy detector determined which one is rename
     and which one is copy too early, which made it impossible
     to later introduce diffcore transformers to reorder
     patches.  This patch fixes it by moving that logic to the
     very end of the processing.

 (2) Earlier output routine diff_flush() was pruning all the
     "no-change" entries indiscriminatingly.  This was done due
     to my false assumption that one of the requirements in the
     diff-raw output was not to show such an entry (which
     resulted in my incorrect comment about "diff-helper never
     being able to be equivalent to built-in diff driver").  My
     special thanks go to Linus for correcting me about this.
     When we produce diff-raw output, for the downstream to be
     able to tell renames from copies, sometimes it _is_
     necessary to output "no-change" entries, and this patch
     adds diffcore_prune() function for doing it.

 (3) Earlier diff_filepair structure was trying to be not too
     specific about rename/copy operations, but the purpose of
     the structure was to record one or two paths, which _was_
     indeed about rename/copy.  This patch discards xfrm_msg
     field which was trying to be generic for this wrong reason,
     and introduces a couple of fields (rename_score and
     rename_rank) that are explicitly specific to rename/copy
     logic.  One thing to note is that the information in a
     single diff_filepair structure _still_ does not distinguish
     renames from copies, and it is deliberately so.  This is to
     allow patches to be reordered in later stages.

 (4) This patch also adds some tests about diff-raw format
     output and makes sure that necessary "no-change" entries
     appear on the output.

Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-23 11:49:30 -07:00
Junio C Hamano
6b14d7faf0 [PATCH] Diffcore updates.
This moves the path selection logic from individual programs to a new
diffcore transformer (diff-tree still needs to have its own for
performance reasons).  Also the header printing code in diff-tree was
tweaked not to produce anything when pickaxe is in effect and there is
nothing interesting to report.  An interesting example is the following
in the GIT archive itself:

    $ git-whatchanged -p -C -S'or something in a real script'

Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-22 10:17:50 -07:00
Junio C Hamano
81e50eabf0 [PATCH] The diff-raw format updates.
Update the diff-raw format as Linus and I discussed, except that
it does not use sequence of underscore '_' letters to express
nonexistence.  All '0' mode is used for that purpose instead.

The new diff-raw format can express rename/copy, and the earlier
restriction that -M and -C _must_ be used with the patch format
output is no longer necessary.  The patch makes -M and -C flags
independent of -p flag, so you need to say git-whatchanged -M -p
to get the diff/patch format.

Updated are both documentations and tests.

Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-21 22:49:19 -07:00
Junio C Hamano
38c6f78059 [PATCH] Prepare diffcore interface for diff-tree header supression.
This does not actually supress the extra headers when pickaxe is
used, but prepares enough support for diff-tree to implement it.

Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-21 22:49:19 -07:00
Junio C Hamano
52e9578985 [PATCH] Introducing software archaeologist's tool "pickaxe".
This steals the "pickaxe" feature from JIT and make it available
to the bare Plumbing layer.  From the command line, the user
gives a string he is intersted in.

Using the diff-core infrastructure previously introduced, it
filters the differences to limit the output only to the diffs
between <src> and <dst> where the string appears only in one but
not in the other.  For example:

 $ ./git-rev-list HEAD | ./git-diff-tree -Sdiff-tree-helper --stdin -M

would show the diffs that touch the string "diff-tree-helper".

In real software-archaeologist application, you would typically
look for a few to several lines of code and see where that code
came from.

The "pickaxe" module runs after "rename/copy detection" module,
so it even crosses the file rename boundary, as the above
example demonstrates.

Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-21 09:58:03 -07:00