kernel/git - git - PowerEL Git System

Commit Graph

Author	SHA1	Message	Date
Ramsay Jones	87f1625836	xdiff/xprepare: fix a memory leak The xdl_prepare_env() function may initialise an xdlclassifier_t data structure via xdl_init_classifier(), which allocates memory to several fields, for example 'rchash', 'rcrecs' and 'ncha'. If this function later exits due to the failure of xdl_optimize_ctxs(), then this xdlclassifier_t structure, and the memory allocated to it, is not cleaned up. In order to fix the memory leak, insert a call to xdl_free_classifier() before returning. Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>	9 years ago
Ramsay Jones	5cd6978a9c	xdiff/xprepare: use the XDF_DIFF_ALG() macro to access flag bits Commit `307ab20b3` ("xdiff: PATIENCE/HISTOGRAM are not independent option bits", 19-02-2012) introduced the XDF_DIFF_ALG() macro to access the flag bits used to represent the diff algorithm requested. In addition, code which had used explicit manipulation of the flag bits was changed to use the macros. However, one example of direct manipulation remains. Update this code to use the XDF_DIFF_ALG() macro. Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>	9 years ago
Junio C Hamano	307ab20b33	xdiff: PATIENCE/HISTOGRAM are not independent option bits Because the default Myers, patience and histogram algorithms cannot be in effect at the same time, XDL_PATIENCE_DIFF and XDL_HISTOGRAM_DIFF are not independent bits. Instead of wasting one bit per algorithm, define a few macros to access the few bits they occupy and update the code that access them. Signed-off-by: Junio C Hamano <gitster@pobox.com>	13 years ago
René Scharfe	c5aa90682f	Revert removal of multi-match discard heuristic in 27af01 `27af01d` (xdiff/xprepare: improve O(n*m) performance in xdl_cleanup_records(), 2011-08-17) was supposed to be a performance boost only. However, it unexpectedly changed the behaviour of diff. Revert a part of `27af01d` that removes logic that mark lines as "multi-match" (ie. dis[i] == 2). This was preventing the multi-match discard heuristic (performed in xdl_cleanup_records() and xdl_clean_mmatch()) from executing. Reported-by: Alexander Pepper <pepper@inf.fu-berlin.de> Signed-off-by: René Scharfe <rene.scharfe@lsrfire.ath.cx> Signed-off-by: Tay Ray Chuan <rctay89@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>	14 years ago
Tay Ray Chuan	2738bc3f09	xdiff/xprepare: initialise xdlclassifier_t cf in xdl_prepare_env() Ensure that the xdl_free_classifier() call on xdlclassifier_t cf is safe even if xdl_init_classifier() isn't called. This may occur in the case where diff is run with --histogram and a call to, say, xdl_prepare_ctx() fails. Signed-off-by: Tay Ray Chuan <rctay89@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>	14 years ago
Tay Ray Chuan	27af01d552	xdiff/xprepare: improve O(nm) performance in xdl_cleanup_records() In xdl_cleanup_records(), we see O(nm) performance, where n is the number of records from xdf->dstart to xdf->dend, and m is the size of a bucket in xdf->rhash (<= by mlim). Here, we improve this to O(n) by pre-computing nm (in rcrec->len(1\|2)) in xdl_classify_record(). Reported-by: Marat Radchenko <marat@slonopotamus.org> Signed-off-by: Tay Ray Chuan <rctay89@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>	14 years ago
Tay Ray Chuan	739864b1ff	xdiff: do away with xdl_mmfile_next() Given our simple mmfile structure, xdl_mmfile_next() calls are redundant. Do away with calls to them. Signed-off-by: Tay Ray Chuan <rctay89@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>	14 years ago
Tay Ray Chuan	86abba8015	xdiff/xprepare: use a smaller sample size for histogram diff For histogram diff, we can afford a smaller sample size and thus a poorer estimate of the number of lines, as the hash table (rhash) won't be filled up/grown. This is safe as the final count of lines (xdf.nrecs) will be updated correctly anyway by xdl_prepare_ctx(). This gives us a small boost in performance. Signed-off-by: Tay Ray Chuan <rctay89@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>	14 years ago
Tay Ray Chuan	9f37c27593	xdiff/xprepare: skip classification xdiff performs "classification" of records (xdl_classify_record()), replacing hashes (xrecord_t.ha) with a unique identifier of the record/line and building a hash table (xrecord_t.rhash) of records. This is then used to "cleanup" records (xdl_cleanup_records()). We don't need any of that in histogram diff, so we omit calls to these functions. We also skip allocating memory to the hash table, rhash, as it is no longer used. This gives us a small boost in performance. Signed-off-by: Tay Ray Chuan <rctay89@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>	14 years ago
Tay Ray Chuan	159607a8f1	xdiff/xprepare: refactor abort cleanups Group free()'s that are called when a malloc() fails in xdl_prepare_ctx(), making for more readable code. Also add a free() on ha, in case future git hackers add allocs after the ha malloc. Signed-off-by: Tay Ray Chuan <rctay89@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>	14 years ago
Tay Ray Chuan	452f4fa51e	xdiff/xprepare: use memset() Use memset() instead of a for loop to initialize. This could give a performance advantage. Signed-off-by: Tay Ray Chuan <rctay89@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>	14 years ago
Johannes Schindelin	92b7de93fb	Implement the patience diff algorithm The patience diff algorithm produces slightly more intuitive output than the classic Myers algorithm, as it does not try to minimize the number of +/- lines first, but tries to preserve the lines that are unique. To this end, it first determines lines that are unique in both files, then the maximal sequence which preserves the order (relative to both files) is extracted. Starting from this initial set of common lines, the rest of the lines is handled recursively, with Myers' algorithm as a fallback when the patience algorithm fails (due to no common unique lines). This patch includes memory leak fixes by Pierre Habouzit. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>	16 years ago
Davide Libenzi	733070bea9	xdiff: give up scanning similar lines early In a corner case of large files whose lines do not match uniquely, the loop to eliminate a line that matches multiple locations adjacent to a run of lines that do not uniquely match wasted too much cycles. Fix this by giving up early after scanning 100 lines in both direction. Signed-off-by: Junio C Hamano <gitster@pobox.com>	16 years ago
Davide Libenzi	9b28d55401	xdiff: give up scanning similar lines early In a corner case of large files whose lines do not match uniquely, the loop to eliminate a line that matches multiple locations adjacent to a run of lines that do not uniquely match wasted too much cycles. Fix this by giving up early after scanning 100 lines in both direction. Signed-off-by: Junio C Hamano <gitster@pobox.com>	16 years ago
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>	18 years ago
Johannes Schindelin	0d21efa51c	Teach diff about -b and -w flags This adds -b (--ignore-space-change) and -w (--ignore-all-space) flags to diff. The main part of the patch is teaching libxdiff about it. [jc: renamed xdl_line_match() to xdl_recmatch() since the former is used for different purposes in xpatchi.c which is in the parts of the upstream source we do not use.] Signed-off-by: Johannes Schindelin <Johannes.Schindelin@gmx.de> Signed-off-by: Junio C Hamano <junkio@cox.net>	19 years ago
Davide Libenzi	ca557afff9	Clean-up trivially redundant diff. Also corrects the line numbers in unified output when using zero lines context.	19 years ago
Linus Torvalds	3443546f6e	Use a real built-in diff generator 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>	19 years ago

20 Commits (2944a94c6b74d3941f63d1f4eee5bdfbbf5cd400)