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2016-04-03Merge branch 'rj/xdiff-prepare-plug-leak-on-error-codepath'Libravatar Junio C Hamano1-1/+2
A small memory leak in an error codepath has been plugged in xdiff code. * rj/xdiff-prepare-plug-leak-on-error-codepath: xdiff/xprepare: fix a memory leak xdiff/xprepare: use the XDF_DIFF_ALG() macro to access flag bits
2016-03-04xdiff/xprepare: fix a memory leakLibravatar Ramsay Jones1-0/+1
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>
2016-03-04xdiff/xprepare: use the XDF_DIFF_ALG() macro to access flag bitsLibravatar Ramsay Jones1-1/+1
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>
2016-02-26Merge branch 'ps/plug-xdl-merge-leak'Libravatar Junio C Hamano1-2/+7
* ps/plug-xdl-merge-leak: xdiff/xmerge: fix memory leak in xdl_merge
2016-02-26Merge branch 'jk/no-diff-emit-common'Libravatar Junio C Hamano2-19/+0
"git merge-tree" used to mishandle "both sides added" conflict with its own "create a fake ancestor file that has the common parts of what both sides have added and do a 3-way merge" logic; this has been updated to use the usual "3-way merge with an empty blob as the fake common ancestor file" approach used in the rest of the system. * jk/no-diff-emit-common: xdiff: drop XDL_EMIT_COMMON merge-tree: drop generate_common strategy merge-one-file: use empty blob for add/add base
2016-02-23xdiff/xmerge: fix memory leak in xdl_mergeLibravatar Patrick Steinhardt1-2/+7
When building the script for the second file that is to be merged we have already allocated memory for data structures related to the first file. When we encounter an error in building the second script we only free allocated memory related to the second file before erroring out. Fix this memory leak by also releasing allocated memory related to the first file. Helped-by: Johannes Schindelin <Johannes.Schindelin@gmx.de> Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-22xdiff: drop XDL_EMIT_COMMONLibravatar Jeff King2-19/+0
There are no more callers that use this mode, and none likely to be added (as our xdl_merge() eliminates the common use of it for generating 3-way merge bases). This is effectively a revert of a9ed376 (xdiff: generate "anti-diffs" aka what is common to two files, 2006-06-28), though of course trying to revert that ancient commit directly produces many textual conflicts. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-01-27merge-file: ensure that conflict sections match eol styleLibravatar Johannes Schindelin1-14/+23
In the previous patch, we made sure that the conflict markers themselves match the end-of-line style of the input files. However, this still left out the conflicting text itself: if it lacks a trailing newline, we add one, and should add a carriage return when appropriate, too. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-01-27merge-file: let conflict markers match end-of-line style of the contextLibravatar Johannes Schindelin1-4/+57
When merging files with CR/LF line endings, the conflict markers should match those, lest the output file has mixed line endings. This is particularly of interest on Windows, where some editors get *really* confused by mixed line endings. The original version of this patch by Beat Bolli respected core.eol, and a subsequent improvement by this developer also respected gitattributes. This approach was suboptimal, though: `git merge-file` was invented as a drop-in replacement for GNU merge and as such has no problem operating outside of any repository at all! Another problem with the original approach was pointed out by Junio Hamano: legacy repositories might have their text files committed using CR/LF line endings (and core.eol and the gitattributes would give us a false impression there). Therefore, the much superior approach is to simply match the context's line endings, if any. We actually do not have to look at the *entire* context at all: if the files are all LF-only, or if they all have CR/LF line endings, it is sufficient to look at just a *single* line to match that style. And if the line endings are mixed anyway, it is *still* okay to imitate just a single line's eol: we will just add to the pile of mixed line endings, and there is nothing we can do about that. So what we do is: we look at the line preceding the conflict, falling back to the line preceding that in case it was the last line and had no line ending, falling back to the first line, first in the first post-image, then the second post-image, and finally the pre-image. If we find consistent CR/LF (or undecided) end-of-line style, we match that, otherwise we use LF-only line endings for the conflict markers. Note that while it is true that there have to be at least two lines we can look at (otherwise there would be no conflict), the same is not true for line *endings*: the three files in question could all consist of a single line without any line ending, each. In this case we fall back to using LF-only. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-30git-merge-file: do not add LF at EOF while applying unrelated changeLibravatar Max Kirillov1-2/+2
If 'current-file' does not contain LF at EOF, and change between 'base-file' and 'other-file' does not change any line close to EOF, the 3-way merge should not add LF to EOF. This is what 'diff3 -m' does, and seems to be a reasonable expectation. The change which introduced the behavior is cd1d61c44f. It always calls function xdl_recs_copy() for sides with add_nl == 1. In fact, it looks like the only case when this is needed is when 2 files are being union-merged, and they do not have LF at EOF (strictly speaking, the first of them). Add tests: * "merge without conflict (missing LF at EOF, away from change in the other file)" and "merge does not add LF away of change", to demonstrate the changed behavior. * "conflict at EOF without LF resolved by --union", to verify that the union-merge at the end inerts newline between versions. * some more tests which I felt like not covering the functionality well Signed-off-by: Max Kirillov <max@max630.net> Acked-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-10-16C: have space around && and || operatorsLibravatar Junio C Hamano1-1/+1
Correct all hits from git grep -e '\(&&\|||\)[^ ]' -e '[^ ]\(&&\|||\)' -- '*.c' i.e. && or || operators that are followed by anything but a SP, or that follow something other than a SP or a HT, so that these operators have a SP around it when necessary. We usually refrain from making this kind of a tree-wide change in order to avoid unnecessary conflicts with other "real work" patches, but in this case, the end result does not have a potentially cumbersome tree-wide impact, while this is a tree-wide cleanup. Fixes to compat/regex/regcomp.c and xdiff/xemit.c are to replace a HT immediately after && with a SP. This is based on Felipe's patch to bultin/symbolic-ref.c; I did all the finding out what other files in the whole tree need to be fixed and did the fix and also the log message while reviewing that single liner, so any screw-ups in this version are mine. Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-06-19diff: add --ignore-blank-lines optionLibravatar Antoine Pelisse7-8/+89
The goal of the patch is to introduce the GNU diff -B/--ignore-blank-lines as closely as possible. The short option is not available because it's already used for "break-rewrites". When this option is used, git-diff will not create hunks that simply add or remove empty lines, but will still show empty lines addition/suppression if they are close enough to "valuable" changes. There are two differences between this option and GNU diff -B option: - GNU diff doesn't have "--inter-hunk-context", so this must be handled - The following sequence looks like a bug (context is displayed twice): $ seq 5 >file1 $ cat <<EOF >file2 change 1 2 3 4 5 change EOF $ diff -u -B file1 file2 --- file1 2013-06-08 22:13:04.471517834 +0200 +++ file2 2013-06-08 22:13:23.275517855 +0200 @@ -1,5 +1,7 @@ +change 1 2 + 3 4 5 @@ -3,3 +5,4 @@ 3 4 5 +change So here is a more thorough description of the option: - real changes are interesting - blank lines that are close enough (less than context size) to interesting changes are considered interesting (recursive definition) - "context" lines are used around each hunk of interesting changes - If two hunks are separated by less than "inter-hunk-context", they will be merged into one. The implementation does the "interesting changes selection" in a single pass. Signed-off-by: Antoine Pelisse <apelisse@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-04-12Correct common spelling mistakes in comments and testsLibravatar Stefano Lattarini2-2/+2
Most of these were found using Lucas De Marchi's codespell tool. Signed-off-by: Stefano Lattarini <stefano.lattarini@gmail.com> Signed-off-by: Jonathan Nieder <jrnieder@gmail.com> Acked-by: Matthieu Moy <Matthieu.Moy@imag.fr> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-05-25Merge branch 'rs/xdiff-fast-hash-fix'Libravatar Junio C Hamano1-15/+15
Fixes compilation issue on 32-bit in an earlier series.
2012-05-23xdiff: import new 32-bit version of count_masked_bytes()Libravatar René Scharfe1-13/+5
Import the latest 32-bit implementation of count_masked_bytes() from Linux (arch/x86/include/asm/word-at-a-time.h). It's shorter and avoids overflows and negative numbers. This fixes test failures on 32-bit, where negative partial results had been shifted right using the "wrong" method (logical shift right instead of arithmetic short right). The compiler is free to chose the method, so it was only wrong in the sense that it didn't work as intended by us. Reported-by: Øyvind A. Holm <sunny@sunbase.org> Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-05-23xdiff: avoid more compiler warnings with XDL_FAST_HASH on 32-bit machinesLibravatar René Scharfe1-1/+7
Hide literals that can cause compiler warnings for 32-bit architectures in expressions that evaluate to small numbers there. Some compilers warn that 0x0001020304050608 won't fit into a 32-bit long, others that shifting right by 56 bits clears a 32-bit value completely. The correct values are calculated in the 64-bit case, which is all that matters in this if-branch. Reported-by: Øyvind A. Holm <sunny@sunbase.org> Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx> Acked-by: Thomas Rast <trast@student.ethz.ch> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-05-22xdiff: avoid compiler warnings with XDL_FAST_HASH on 32-bit machinesLibravatar René Scharfe1-3/+5
Import macro REPEAT_BYTE from Linux (arch/x86/include/asm/word-at-a-time.h) to avoid 64-bit integer literals, which cause some 32-bit compilers to print warnings. Reported-by: Øyvind A. Holm <sunny@sunbase.org> Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-05-09xdiff: remove unused functionsLibravatar René Scharfe2-46/+0
The functions xdl_cha_first(), xdl_cha_next() and xdl_atol() are not used by us. While removing them increases the difference to the upstream version of libxdiff, it only adds a bit to the more than 600 differing lines in xutils.c (mmfile_t management was simplified significantly when the library was imported initially). Besides, if upstream modifies these functions in the future, we won't need to think about importing those changes, so in that sense it makes tracking modifications easier. Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-05-09xdiff: remove emit_func() and xdi_diff_hunks()Libravatar René Scharfe2-6/+1
The functions are unused now, remove them. Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-05-09xdiff: add hunk_func()Libravatar René Scharfe2-0/+22
Add a way to register a callback function that is gets passed the start line and line count of each hunk of a diff. Only standard types are used. Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-05-02Merge branch 'tr/xdiff-fast-hash'Libravatar Junio C Hamano1-0/+106
Use word-at-a-time comparison to find end of line or NUL (end of buffer), borrowed from the linux-kernel discussion. By Thomas Rast * tr/xdiff-fast-hash: xdiff: choose XDL_FAST_HASH code on sizeof(long) instead of __WORDSIZE xdiff: load full words in the inner loop of xdl_hash_record
2012-05-01xdiff: choose XDL_FAST_HASH code on sizeof(long) instead of __WORDSIZELibravatar Thomas Rast1-29/+23
Darwin does not define __WORDSIZE, and compiles the 32-bit code path on 64-bit systems, resulting in a totally broken git. I could not find an alternative -- other than the platform symbols (__x86_64__ etc.) -- that does the test in the preprocessor. However, we can also just test for the size of a 'long', which is what really matters here. Any compiler worth its salt will leave only the branch relevant for its platform, and indeed on Linux/GCC the numbers don't change: Test tr/darwin-xdl-fast-hash origin/next origin/master ------------------------------------------------------------------------------------------------------------------ 4000.1: log -3000 (baseline) 0.09(0.07+0.01) 0.09(0.07+0.01) -5.5%* 0.09(0.07+0.01) -4.1% 4000.2: log --raw -3000 (tree-only) 0.47(0.41+0.05) 0.47(0.40+0.05) -0.5% 0.45(0.38+0.06) -3.5%. 4000.3: log -p -3000 (Myers) 1.81(1.67+0.12) 1.81(1.67+0.13) +0.3% 1.99(1.84+0.12) +10.2%*** 4000.4: log -p -3000 --histogram 1.79(1.66+0.11) 1.80(1.67+0.11) +0.4% 1.96(1.82+0.10) +9.2%*** 4000.5: log -p -3000 --patience 2.17(2.02+0.13) 2.20(2.04+0.13) +1.3%. 2.33(2.18+0.13) +7.4%*** ------------------------------------------------------------------------------------------------------------------ Significance hints: '.' 0.1 '*' 0.05 '**' 0.01 '***' 0.001 Noticed-by: Brian Gernhardt <brian@gernhardtsoftware.com> Signed-off-by: Thomas Rast <trast@student.ethz.ch> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-04-15Merge branch 'jc/diff-algo-cleanup'Libravatar Junio C Hamano5-21/+18
Resurrects the preparatory clean-up patches from another topic that was discarded, as this would give a saner foundation to build on diff.algo configuration option series. * jc/diff-algo-cleanup: xdiff: PATIENCE/HISTOGRAM are not independent option bits xdiff: remove XDL_PATCH_* macros
2012-04-09xdiff: load full words in the inner loop of xdl_hash_recordLibravatar Thomas Rast1-0/+112
Redo the hashing loop in xdl_hash_record in a way that loads an entire 'long' at a time, using masking tricks to see when and where we found the terminating '\n'. I stole inspiration and code from the posts by Linus Torvalds around https://lkml.org/lkml/2012/3/2/452 https://lkml.org/lkml/2012/3/5/6 His method reads the buffers in sizeof(long) increments, and may thus overrun it by at most sizeof(long)-1 bytes before it sees the final newline (or hits the buffer length check). I considered padding out all buffers by a suitable amount to "catch" the overrun, but * this does not work for mmap()'d buffers: if you map 4096+8 bytes from a 4096 byte file, accessing the last 8 bytes results in a SIGBUS on my machine; and * it would also be extremely ugly because it intrudes deep into the unpacking machinery. So I adapted it to not read beyond the buffer at all. Instead, it reads the final partial word byte-by-byte and strings it together. Then it can use the same logic as before to finish the hashing. So far we enable this only on x86_64, where it provides nice speedup for diff-related work: Test origin/next tr/xdiff-fast-hash ----------------------------------------------------------------------------- 4000.1: log -3000 (baseline) 0.07(0.05+0.02) 0.08(0.06+0.02) +14.3% 4000.2: log --raw -3000 (tree-only) 0.37(0.33+0.04) 0.37(0.32+0.04) +0.0% 4000.3: log -p -3000 (Myers) 1.75(1.65+0.09) 1.60(1.49+0.10) -8.6% 4000.4: log -p -3000 --histogram 1.73(1.62+0.09) 1.58(1.49+0.08) -8.7% 4000.5: log -p -3000 --patience 2.11(2.00+0.10) 1.94(1.80+0.11) -8.1% Perhaps other platforms could also benefit. However it does NOT work on big-endian systems! [jc: minimum style and compilation fixes] Signed-off-by: Thomas Rast <trast@student.ethz.ch> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-02-19xdiff: PATIENCE/HISTOGRAM are not independent option bitsLibravatar Junio C Hamano5-16/+18
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>
2012-02-19xdiff: remove XDL_PATCH_* macrosLibravatar Junio C Hamano1-5/+0
These are not used anywhere in our codebase, and the bit assignment definition is merely confusing. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-01-29Merge branch 'rs/diff-postimage-in-context'Libravatar Junio C Hamano1-6/+6
* rs/diff-postimage-in-context: xdiff: print post-image for common records instead of pre-image
2012-01-06xdiff: print post-image for common records instead of pre-imageLibravatar René Scharfe1-6/+6
Normally it doesn't matter if we show the pre-image or th post-image for the common parts of a diff because they are the same. If white-space changes are ignored they can differ, though. The new text after applying the diff is more interesting in that case, so show that instead of the old contents. Note: GNU diff shows the pre-image. Suggested-by: Junio C Hamano <gitster@pobox.com> Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-10-19Merge branch 'rs/diff-whole-function'Libravatar Junio C Hamano2-16/+70
* rs/diff-whole-function: diff: add option to show whole functions as context xdiff: factor out get_func_line()
2011-10-13Merge branch 'rs/diff-cleanup-records-fix'Libravatar Junio C Hamano1-3/+7
* rs/diff-cleanup-records-fix: diff: resurrect XDF_NEED_MINIMAL with --minimal Revert removal of multi-match discard heuristic in 27af01
2011-10-10diff: add option to show whole functions as contextLibravatar René Scharfe2-6/+49
Add the option -W/--function-context to git diff. It is similar to the same option of git grep and expands the context of change hunks so that the whole surrounding function is shown. This "natural" context can allow changes to be understood better. Note: GNU patch doesn't like diffs generated with the new option; it seems to expect context lines to be the same before and after changes. git apply doesn't complain. This implementation has the same shortcoming as the one in grep, namely that there is no way to explicitly find the end of a function. That means that a few lines of extra context are shown, right up to the next recognized function begins. It's already useful in its current form, though. The function get_func_line() in xdiff/xemit.c is extended to work forward as well as backward to find post-context as well as pre-context. It returns the position of the first found matching line. The func_line parameter is made optional, as we don't need it for -W. The enhanced function is then used in xdl_emit_diff() to extend the context as needed. If the added context overlaps with the next change, it is merged into the current hunk. Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-10-10xdiff: factor out get_func_line()Libravatar René Scharfe1-16/+27
Move the code to search for a function line to be shown in the hunk header into its own function and to make returning the length-limited result string easier, introduce struct func_line. Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-09-26Revert removal of multi-match discard heuristic in 27af01Libravatar René Scharfe1-3/+7
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>
2011-09-06Merge branch 'rc/histogram-diff'Libravatar Junio C Hamano1-0/+2
* rc/histogram-diff: xdiff/xprepare: initialise xdlclassifier_t cf in xdl_prepare_env()
2011-08-31xdiff/xprepare: initialise xdlclassifier_t cf in xdl_prepare_env()Libravatar Tay Ray Chuan1-0/+2
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>
2011-08-17Merge branch 'rc/histogram-diff' into HEADLibravatar Junio C Hamano8-125/+470
* rc/histogram-diff: xdiff/xhistogram: drop need for additional variable xdiff/xhistogram: rely on xdl_trim_ends() xdiff/xhistogram: rework handling of recursed results xdiff: do away with xdl_mmfile_next() Make test number unique xdiff/xprepare: use a smaller sample size for histogram diff xdiff/xprepare: skip classification teach --histogram to diff t4033-diff-patience: factor out tests xdiff/xpatience: factor out fall-back-diff function xdiff/xprepare: refactor abort cleanups xdiff/xprepare: use memset() Conflicts: xdiff/xprepare.c
2011-08-17xdiff/xprepare: improve O(n*m) performance in xdl_cleanup_records()Libravatar Tay Ray Chuan1-36/+50
In xdl_cleanup_records(), we see O(n*m) 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>
2011-08-08xdiff/xhistogram: drop need for additional variableLibravatar Tay Ray Chuan1-5/+4
Having an additional variable (ptr) instead of changing line(1|2) and count(1|2) was for debugging purposes. Signed-off-by: Tay Ray Chuan <rctay89@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-08-08xdiff/xhistogram: rely on xdl_trim_ends()Libravatar Tay Ray Chuan1-27/+4
Do away with reduce_common_start_end() and use xdf->dstart and xdf->dend set by xdl_trim_ends() that similarly tells us where the first unmatched line from the start and end occurs. Signed-off-by: Tay Ray Chuan <rctay89@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-08-08xdiff/xhistogram: rework handling of recursed resultsLibravatar Tay Ray Chuan1-6/+9
Previously we were over-complicating matters by trying to combine the recursed results. Now, terminate immediately if a recursive call failed and return its result. Signed-off-by: Tay Ray Chuan <rctay89@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-08-03xdiff: do away with xdl_mmfile_next()Libravatar Tay Ray Chuan3-20/+2
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>
2011-07-12xdiff/xprepare: use a smaller sample size for histogram diffLibravatar Tay Ray Chuan3-10/+17
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>
2011-07-12xdiff/xprepare: skip classificationLibravatar Tay Ray Chuan1-8/+16
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>
2011-07-12teach --histogram to diffLibravatar Tay Ray Chuan4-0/+390
Port JGit's HistogramDiff algorithm over to C. Rough numbers (TODO) show that it is faster than its --patience cousin, as well as the default Meyers algorithm. The implementation has been reworked to use structs and pointers, instead of bitmasks, thus doing away with JGit's 2^28 line limit. We also use xdiff's default hash table implementation (xdl_hash_bits() with XDL_HASHLONG()) for convenience. Signed-off-by: Tay Ray Chuan <rctay89@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-07-07xdiff/xpatience: factor out fall-back-diff functionLibravatar Tay Ray Chuan3-25/+35
This is in preparation for the histogram diff algorithm, which will also re-use much of the code to call the default Meyers diff algorithm. Signed-off-by: Tay Ray Chuan <rctay89@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-07-07xdiff/xprepare: refactor abort cleanupsLibravatar Tay Ray Chuan1-59/+32
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>
2011-07-07xdiff/xprepare: use memset()Libravatar Tay Ray Chuan1-7/+3
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>
2010-11-17Merge branch 'cb/diff-fname-optim'Libravatar Junio C Hamano1-24/+14
* cb/diff-fname-optim: diff: avoid repeated scanning while looking for funcname do not search functions for patch ID add rebase patch id tests
2010-10-06xdiff: cast arguments for ctype functions to unsigned charLibravatar Jonathan Nieder3-10/+11
The ctype functions isspace(), isalnum(), et al take an integer argument representing an unsigned character, or -1 for EOF. On platforms with a signed char, it is unsafe to pass a char to them without casting it to unsigned char first. Most of git is already shielded against this by the ctype implementation in git-compat-util.h, but xdiff, which uses libc ctype.h, ought to be fixed. Noticed-by: der Mouse <mouse@Rodents-Montreal.ORG> Reported-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-09-30diff: avoid repeated scanning while looking for funcnameLibravatar René Scharfe1-24/+14
For each hunk, xdl_find_func searches the preimage for a function name until the beginning of the file. If the file does not contain any function names, this search has complexity O(n^2) in the number of hunks n. Instead, inline xdl_find_func() and keep track of up to which line we have scanned already and the contents of the last funcname line that we have found. Noticed and a different approach proposed by Clemens Buchacher. This alternative solution was done by René Scharfe. Signed-off-by: Junio C Hamano <gitster@pobox.com>