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2013-10-28pathspec: stop --*-pathspecs impact on internal parse_pathspec() usesLibravatar Nguyễn Thái Ngọc Duy1-1/+3
Normally parse_pathspec() is used on command line arguments where it can do fancy thing like parsing magic on each argument or adding magic for all pathspecs based on --*-pathspecs options. There's another use of parse_pathspec(), where pathspec is needed, but the input is known to be pure paths. In this case we usually don't want --*-pathspecs to interfere. And we definitely do not want to parse magic in these paths, regardless of --literal-pathspecs. Add new flag PATHSPEC_LITERAL_PATH for this purpose. When it's set, --*-pathspecs are ignored, no magic is parsed. And if the caller allows PATHSPEC_LITERAL (i.e. the next calls can take literal magic), then PATHSPEC_LITERAL will be set. This fixes cases where git chokes when GIT_*_PATHSPECS are set because parse_pathspec() indicates it won't take any magic. But GIT_*_PATHSPECS add them anyway. These are export GIT_LITERAL_PATHSPECS=1 git blame -- something git log --follow something git log --merge "git ls-files --with-tree=path" (aka parse_pathspec() in overlay_tree_on_cache()) is safe because the input is empty, and producing one pathspec due to PATHSPEC_PREFER_CWD does not take any magic into account. Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Acked-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-07-15pathspec: support :(literal) syntax for noglob pathspecLibravatar Nguyễn Thái Ngọc Duy1-1/+1
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-07-15tree-diff: remove the use of pathspec's raw[] in follow-rename codepathLibravatar Nguyễn Thái Ngọc Duy1-2/+2
Put a checkpoint to guard unsupported pathspec features in future. Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-07-15remove init_pathspec() in favor of parse_pathspec()Libravatar Nguyễn Thái Ngọc Duy1-5/+5
While at there, move free_pathspec() to pathspec.c Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-07-15remove diff_tree_{setup,release}_pathsLibravatar Nguyễn Thái Ngọc Duy1-14/+4
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-07-15guard against new pathspec magic in pathspec matching codeLibravatar Nguyễn Thái Ngọc Duy1-0/+19
GUARD_PATHSPEC() marks pathspec-sensitive code, basically all those that touch anything in 'struct pathspec' except fields "nr" and "original". GUARD_PATHSPEC() is not supposed to fail. It's mainly to help the designers catch unsupported codepaths. Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-07-15parse_pathspec: add special flag for max_depth featureLibravatar Nguyễn Thái Ngọc Duy1-1/+0
match_pathspec_depth() and tree_entry_interesting() check max_depth field in order to support "git grep --max-depth". The feature activation is tied to "recursive" field, which led to some unwanted activation, e.g. 5c8eeb8 (diff-index: enable recursive pathspec matching in unpack_trees - 2012-01-15). This patch decouples the activation from "recursive" field, puts it in "magic" field instead. This makes sure that only "git grep" can activate this feature. And because parse_pathspec knows when the feature is not used, it does not need to sort pathspec (required for max_depth to work correctly). A small win for non-grep cases. Even though a new magic flag is introduced, no magic syntax is. The magic can be only enabled by parse_pathspec() caller. We might someday want to support ":(maxdepth:10)src." It all depends on actual use cases. max_depth feature cannot be enabled via init_pathspec() anymore. But that's ok because init_pathspec() is on its way to /dev/null. Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-08-27Merge branch 'jk/maint-null-in-trees'Libravatar Junio C Hamano1-4/+4
We do not want a link to 0{40} object stored anywhere in our objects. * jk/maint-null-in-trees: fsck: detect null sha1 in tree entries do not write null sha1s to on-disk index diff: do not use null sha1 as a sentinel value
2012-08-03diff_setup_done(): return voidLibravatar Thomas Rast1-2/+1
diff_setup_done() has historically returned an error code, but lost the last nonzero return in 943d5b7 (allow diff.renamelimit to be set regardless of -M/-C, 2006-08-09). The callers were in a pretty confused state: some actually checked for the return code, and some did not. Let it return void, and patch all callers to take this into account. This conveniently also gets rid of a handful of different(!) error messages that could never be triggered anyway. Note that the function can still die(). Signed-off-by: Thomas Rast <trast@student.ethz.ch> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-07-29diff: do not use null sha1 as a sentinel valueLibravatar Jeff King1-4/+4
The diff code represents paths using the diff_filespec struct. This struct has a sha1 to represent the sha1 of the content at that path, as well as a sha1_valid member which indicates whether its sha1 field is actually useful. If sha1_valid is not true, then the filespec represents a working tree file (e.g., for the no-index case, or for when the index is not up-to-date). The diff_filespec is only used internally, though. At the interfaces to the diff subsystem, callers feed the sha1 directly, and we create a diff_filespec from it. It's at that point that we look at the sha1 and decide whether it is valid or not; callers may pass the null sha1 as a sentinel value to indicate that it is not. We should not typically see the null sha1 coming from any other source (e.g., in the index itself, or from a tree). However, a corrupt tree might have a null sha1, which would cause "diff --patch" to accidentally diff the working tree version of a file instead of treating it as a blob. This patch extends the edges of the diff interface to accept a "sha1_valid" flag whenever we accept a sha1, and to use that flag when creating a filespec. In some cases, this means passing the flag through several layers, making the code change larger than would be desirable. One alternative would be to simply die() upon seeing corrupted trees with null sha1s. However, this fix more directly addresses the problem (while bogus sha1s in a tree are probably a bad thing, it is really the sentinel confusion sending us down the wrong code path that is what makes it devastating). And it means that git is more capable of examining and debugging these corrupted trees. For example, you can still "diff --raw" such a tree to find out when the bogus entry was introduced; you just cannot do a "--patch" diff (just as you could not with any other corrupted tree, as we do not have any content to diff). Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-12-16use custom rename score during --followLibravatar Jeff King1-0/+1
If you provide a custom rename score on the command line, like: git log -M50 --follow foo.c it is completely ignored, and there is no way to --follow with a looser rename score. Instead, let's use the same rename score that will be used for generating diffs. This is convenient, and mirrors what we do with the break-score. You can see an example of it being useful in git.git: $ git log --oneline --summary --follow \ Documentation/technical/api-string-list.txt 86d4b52 string-list: Add API to remove an item from an unsorted list 1d2f80f string_list: Fix argument order for string_list_append e242148 string-list: add unsorted_string_list_lookup() 0dda1d1 Fix two leftovers from path_list->string_list c455c87 Rename path_list to string_list create mode 100644 Documentation/technical/api-string-list.txt $ git log --oneline --summary -M40 --follow \ Documentation/technical/api-string-list.txt 86d4b52 string-list: Add API to remove an item from an unsorted list 1d2f80f string_list: Fix argument order for string_list_append e242148 string-list: add unsorted_string_list_lookup() 0dda1d1 Fix two leftovers from path_list->string_list c455c87 Rename path_list to string_list rename Documentation/technical/{api-path-list.txt => api-string-list.txt} (47%) 328a475 path-list documentation: document all functions and data structures 530e741 Start preparing the API documents. create mode 100644 Documentation/technical/api-path-list.txt You could have two separate rename scores, one for following and one for diff. But almost nobody is going to want that, and it would just be unnecessarily confusing. Besides which, we re-use the diff results from try_to_follow_renames for the actual diff output, which means having them as separate scores is actively wrong. E.g., with the current code, you get: $ git log --oneline --diff-filter=R --name-status \ -M90 --follow git.spec.in 27dedf0 GIT 0.99.9j aka 1.0rc3 R084 git-core.spec.in git.spec.in f85639c Rename the RPM from "git" to "git-core" R098 git.spec.in git-core.spec.in The first one should not be considered a rename by the -M score we gave, but we print it anyway, since we blindly re-use the diff information from the follow (which uses the default score). So this could also be considered simply a bug-fix, as with the current code "-M" is completely ignored when using "--follow". Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-10-27tree_entry_interesting(): give meaningful names to return valuesLibravatar Nguyễn Thái Ngọc Duy1-7/+9
It is a basic code hygiene to avoid magic constants that are unnamed. Besides, this helps extending the value later on for "interesting, but cannot decide if the entry truely matches yet" (ie. prefix matches) Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-10-27tree-walk.c: do not leak internal structure in tree_entry_len()Libravatar Nguyễn Thái Ngọc Duy1-3/+3
tree_entry_len() does not simply take two random arguments and return a tree length. The two pointers must point to a tree item structure, or struct name_entry. Passing random pointers will return incorrect value. Force callers to pass struct name_entry instead of two pointers (with hope that they don't manually construct struct name_entry themselves) Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-06-06Merge branch 'jk/diff-not-so-quick'Libravatar Junio C Hamano1-2/+1
* jk/diff-not-so-quick: diff: futureproof "stop feeding the backend early" logic diff_tree: disable QUICK optimization with diff filter Conflicts: diff.c
2011-05-31diff: futureproof "stop feeding the backend early" logicLibravatar Junio C Hamano1-3/+1
Refactor the "do not stop feeding the backend early" logic into a small helper function and use it in both run_diff_files() and diff_tree() that has the stop-early optimization. We may later add other types of diffcore transformation that require to look at the whole result like diff-filter does, and having the logic in a single place is essential for longer term maintainability. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-05-31diff_tree: disable QUICK optimization with diff filterLibravatar Jeff King1-0/+1
We stop looking for changes early with QUICK, so our diff queue contains only a subset of the changes. However, we don't apply diff filters until later; it will appear at that point as though there are no changes matching our filter, when in reality we simply didn't keep looking for changes long enough. Commit 2cfe8a6 (diff --quiet: disable optimization when --diff-filter=X is used, 2011-03-16) fixes this in some cases by disabling the optimization when a filter is present. However, it only tweaked run_diff_files, missing the similar case in diff_tree. Thus the fix worked only for diffing the working tree and index, but not between trees. Noticed by Yasushi SHOJI. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-05-06Merge branch 'nd/struct-pathspec'Libravatar Junio C Hamano1-33/+20
* nd/struct-pathspec: pathspec: rename per-item field has_wildcard to use_wildcard Improve tree_entry_interesting() handling code Convert read_tree{,_recursive} to support struct pathspec Reimplement read_tree_recursive() using tree_entry_interesting()
2011-03-25Improve tree_entry_interesting() handling codeLibravatar Nguyễn Thái Ngọc Duy1-33/+20
t_e_i() can return -1 or 2 to early shortcut a search. Current code may use up to two variables to handle it. One for saving return value from t_e_i temporarily, one for saving return code 2. The second variable is not needed. If we make sure the first variable does not change until the next t_e_i() call, then we can do something like this: int ret = 0; while (...) { if (ret != 2) { ret = t_e_i(); if (ret < 0) /* no longer interesting */ break; if (ret == 0) /* skip this round */ continue; } /* ret > 0, interesting */ } Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-03-22Remove unused variablesLibravatar Johannes Schindelin1-2/+1
Noticed by gcc 4.6.0. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-02-03grep: drop pathspec_matches() in favor of tree_entry_interesting()Libravatar Nguyễn Thái Ngọc Duy1-2/+2
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-02-03tree_entry_interesting(): support depth limitLibravatar Nguyễn Thái Ngọc Duy1-0/+4
This is needed to replace pathspec_matches() in builtin/grep.c. max_depth == -1 means infinite depth. Depth limit is only effective when pathspec.recursive == 1. When pathspec.recursive == 0, the behavior depends on match functions: non-recursive for tree_entry_interesting() and recursive for match_pathspec{,_depth} Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-02-03diff-tree: convert base+baselen to writable strbufLibravatar Nguyễn Thái Ngọc Duy1-68/+52
In traversing trees, a full path is splitted into two parts: base directory and entry. They are however quite often concatenated whenever a full path is needed. Current code allocates a new buffer, do two memcpy(), use it, then release. Instead this patch turns "base" to a writable, extendable buffer. When a concatenation is needed, the callee only needs to append "entry" to base, use it, then truncate the entry out again. "base" must remain unchanged before and after entering a function. This avoids quite a bit of malloc() and memcpy(). Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-02-03Move tree_entry_interesting() to tree-walk.c and export itLibravatar Nguyễn Thái Ngọc Duy1-112/+0
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-02-03tree_entry_interesting(): remove dependency on struct diff_optionsLibravatar Nguyễn Thái Ngọc Duy1-16/+10
This function can be potentially used in more places than just tree-diff.c. "struct diff_options" does not make much sense outside diff_tree_sha1(). While removing the use of diff_options, it also removes tree_entry_extract() call, which means S_ISDIR() uses the entry->mode directly, without being filtered by canon_mode() (called internally inside tree_entry_extract). The only use of the mode information in this function is to check the type of the entry by giving it to S_ISDIR() macro, and the result does not change with or without canon_mode(), so it is ok to bypass tree_entry_extract(). Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-02-03Convert struct diff_options to use struct pathspecLibravatar Nguyễn Thái Ngọc Duy1-35/+13
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-10-26Merge branch 'en/tree-walk-optim'Libravatar Junio C Hamano1-14/+15
* en/tree-walk-optim: diff_tree(): Skip skip_uninteresting() when all remaining paths interesting tree_entry_interesting(): Make return value more specific tree-walk: Correct bitrotted comment about tree_entry() Document pre-condition for tree_entry_interesting
2010-08-26diff_tree(): Skip skip_uninteresting() when all remaining paths interestingLibravatar Elijah Newren1-13/+12
In 1d848f6 (tree_entry_interesting(): allow it to say "everything is interesting" 2007-03-21), both show_tree() and skip_uninteresting() were modified to determine if all remaining tree entries were interesting. However, the latter returns as soon as it finds the first interesting path, without any way to signal to its caller (namely, diff_tree()) that all remaining paths are interesting, making these extra checks useless. Pass whether all remaining entries are interesting back to diff_tree(), and whenever they are, have diff_tree() skip subsequent calls to skip_uninteresting(). With this change, I measure speedups of 3-4% for the commands $ git rev-list --quiet HEAD -- Documentation/ $ git rev-list --quiet HEAD -- t/ in git.git. Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-08-26tree_entry_interesting(): Make return value more specificLibravatar Elijah Newren1-1/+1
tree_entry_interesting() can signal to its callers not only if the given entry matches one of the specified paths, but whether all remaining paths will (or will not) match. When no paths are specified, all paths are considered interesting, so intead of returning 1 (this path is interesting) return 2 (all paths are interesting). This will allow the caller to avoid calling tree_entry_interesting() again, which theoretically should speed up tree walking. I am not able to measure any actual gains in practice, but it certainly can not hurt and seems to make the code more readable to me. Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-08-26Document pre-condition for tree_entry_interestingLibravatar Elijah Newren1-0/+2
tree_entry_interesting will fail to find appropriate matches if the base directory path is not terminated with a slash. Knowing this earlier would have saved me some debugging time. Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-08-13diff --follow: do call diffcore_std() as necessaryLibravatar Junio C Hamano1-0/+11
Usually, diff frontends populate the output queue with filepairs without any rename information and call diffcore_std() to sort the renames out. When --follow is in effect, however, diff-tree family of frontend has a hack that looks like this: diff-tree frontend -> diff_tree_sha1() . populate diff_queued_diff . if --follow is in effect and there is only one change that creates the target path, then -> try_to_follow_renames() -> diff_tree_sha1() with no pathspec but with -C -> diffcore_std() to find renames . if rename is found, tweak diff_queued_diff and put a single filepair that records the found rename there -> diffcore_std() . tweak elements on diff_queued_diff by - rename detection - path ordering - pickaxe filtering We need to skip parts of the second call to diffcore_std() that is related to rename detection, and do so only when try_to_follow_renames() did find a rename. Earlier 1da6175 (Make diffcore_std only can run once before a diff_flush, 2010-05-06) tried to deal with this issue incorrectly; it unconditionally disabled any second call to diffcore_std(). This hopefully fixes the breakage. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-08-13diff --follow: do not waste cycles while recursingLibravatar Junio C Hamano1-1/+1
The "--follow" logic is called from diff_tree_sha1() function, but the input trees to diff_tree_sha1() are not necessarily the top-level trees (compare_tree_entry() calls it while it recursively descends into subtrees). When a newly created path lives in somewhere deep in the source hierarchy, e.g. "platform/", but the rename source is in a totally different place in the destination hierarchy, e.g. "lang-api/src/com/...", running "try_to_find_renames()" while base is set to "platform/" is a wasted call. We only need to run the rename following at the very top level. Signed-off-by: Junio C Hamano <gitster@pobox.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-07Make git log --follow find copies among unmodified files.Libravatar Bo Yang1-1/+1
'git log --follow <path>' don't track copies from unmodified files, and this patch fix it. Signed-off-by: Bo Yang <struggleyb.nku@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-01-18Performance optimization for detection of modified submodulesLibravatar Jens Lehmann1-4/+4
In the worst case is_submodule_modified() got called three times for each submodule. The information we got from scanning the whole submodule tree the first time can be reused instead. New parameters have been added to diff_change() and diff_addremove(), the information is stored in a new member of struct diff_filespec. Its value is then reused instead of calling is_submodule_modified() again. When no explicit "-dirty" is needed in the output the call to is_submodule_modified() is not necessary when the submodules HEAD already disagrees with the ref of the superproject, as this alone marks it as modified. To achieve that, get_stat_data() got an extra argument. Signed-off-by: Jens Lehmann <Jens.Lehmann@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-07-29diff: Rename QUIET internal option to QUICKLibravatar Junio C Hamano1-1/+1
The option "QUIET" primarily meant "find if we have _any_ difference as quick as possible and report", which means we often do not even have to look at blobs if we know the trees are different by looking at the higher level (e.g. "diff-tree A B"). As a side effect, because there is no point showing one change that we happened to have found first, it also enables NO_OUTPUT and EXIT_WITH_STATUS options, making the end result look quiet. Rename the internal option to QUICK to reflect this better; it also makes grepping the source tree much easier, as there are other kinds of QUIET option everywhere. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-07-29diff: change semantics of "ignore whitespace" optionsLibravatar Junio C Hamano1-1/+2
Traditionally, the --ignore-whitespace* options have merely meant to tell the diff output routine that some class of differences are not worth showing in the textual diff output, so that the end user has easier time to review the remaining (presumably more meaningful) changes. These options never affected the outcome of the command, given as the exit status when the --exit-code option was in effect (either directly or indirectly). When you have only whitespace changes, however, you might expect git diff -b --exit-code to report that there is _no_ change with zero exit status. Change the semantics of --ignore-whitespace* options to mean more than "omit showing the difference in text". The exit status, when --exit-code is in effect, is computed by checking if we found any differences at the path level, while diff frontends feed filepairs to the diffcore engine. When "ignore whitespace" options are in effect, we defer this determination until the very end of diffcore transformation. We simply do not know until the textual diff is generated, which comes very late in the pipeline. When --quiet is in effect, various diff frontends optimize by breaking out early from the loop that enumerates the filepairs, when we find the first path level difference; when --ignore-whitespace* is used the above change automatically disables this optimization. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-07-01Merge branch 'ne/maint-1.6.0-diff-tree-t-r-show-directory'Libravatar Junio C Hamano1-0/+6
* ne/maint-1.6.0-diff-tree-t-r-show-directory: diff-tree -r -t: include added/removed directories in the output
2009-06-13diff-tree -r -t: include added/removed directories in the outputLibravatar Nick Edelen1-0/+6
We used to include only the modified and typechanged directories in the ouptut, but for consistency's sake, we should also include added and removed ones as well. This makes the output more consistent, but it may break existing scripts that expect to see the current output which has long been the established behaviour. Signed-off-by: Nick Edelen <sirnot@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-04-22Fix typos / spelling in commentsLibravatar Mike Ralphson1-1/+1
Signed-off-by: Mike Ralphson <mike@abacus.co.uk> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-04-01tree_entry_interesting: a pathspec only matches at directory boundaryLibravatar Björn Steinbrink1-3/+9
Previously the code did a simple prefix match, which means that a path in a directory "frotz/" would have matched with pathspec "f". Signed-off-by: Björn Steinbrink <B.Steinbrink@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-08-31'git foo' program identifies itself without dash in die() messagesLibravatar Junio C Hamano1-1/+1
This is a mechanical conversion of all '*.c' files with: s/((?:die|error|warning)\("git)-(\S+:)/$1 $2/; The result was manually inspected and no false positive was found. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-07-16Fix buffer overflow in git diffLibravatar Dmitry Potapov1-5/+22
If PATH_MAX on your system is smaller than a path stored, it may cause buffer overflow and stack corruption in diff_addremove() and diff_change() functions when running git-diff Signed-off-by: Dmitry Potapov <dpotapov@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-12-12Fix small memory leaks induced by diff_tree_setup_pathsLibravatar Mike Hommey1-0/+2
Run diff_tree_release_paths in the appropriate places, and add a test to avoid NULL dereference. Better safe than sorry. Signed-off-by: Mike Hommey <mh@glandium.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-11-11Make the diff_options bitfields be an unsigned with explicit masks.Libravatar Pierre Habouzit1-7/+7
reverse_diff was a bit-value in disguise, it's merged in the flags now. Signed-off-by: Pierre Habouzit <madcoder@debian.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-10-21Fix diffcore-break total breakageLibravatar Linus Torvalds1-0/+1
Ok, so on the kernel list, some people noticed that "git log --follow" doesn't work too well with some files in the x86 merge, because a lot of files got renamed in very special ways. In particular, there was a pattern of doing single commits with renames that looked basically like - rename "filename.h" -> "filename_64.h" - create new "filename.c" that includes "filename_32.h" or "filename_64.h" depending on whether we're 32-bit or 64-bit. which was preparatory for smushing the two trees together. Now, there's two issues here: - "filename.c" *remained*. Yes, it was a rename, but there was a new file created with the old name in the same commit. This was important, because we wanted each commit to compile properly, so that it was bisectable, so splitting the rename into one commit and the "create helper file" into another was *not* an option. So we need to break associations where the contents change too much. Fine. We have the -B flag for that. When we break things up, then the rename detection will be able to figure out whether there are better alternatives. - "git log --follow" didn't with with -B. Now, the second case was really simple: we use a different "diffopt" structure for the rename detection than the basic one (which we use for showing the diffs). So that second case is trivially fixed by a trivial one-liner that just copies the break_opt values from the "real" diffopts to the one used for rename following. So now "git log -B --follow" works fine: diff --git a/tree-diff.c b/tree-diff.c index 26bdbdd..7c261fd 100644 --- a/tree-diff.c +++ b/tree-diff.c @@ -319,6 +319,7 @@ static void try_to_follow_renames(struct tree_desc *t1, struct tree_desc *t2, co diff_opts.detect_rename = DIFF_DETECT_RENAME; diff_opts.output_format = DIFF_FORMAT_NO_OUTPUT; diff_opts.single_follow = opt->paths[0]; + diff_opts.break_opt = opt->break_opt; paths[0] = NULL; diff_tree_setup_paths(paths, &diff_opts); if (diff_setup_done(&diff_opts) < 0) however, the end result does *not* work. Because our diffcore-break.c logic is totally bogus! In particular: - it used to do if (base_size < MINIMUM_BREAK_SIZE) return 0; /* we do not break too small filepair */ which basically says "don't bother to break small files". But that "base_size" is the *smaller* of the two sizes, which means that if some large file was rewritten into one that just includes another file, we would look at the (small) result, and decide that it's smaller than the break size, so it cannot be worth it to break it up! Even if the other side was ten times bigger and looked *nothing* like the samell file! That's clearly bogus. I replaced "base_size" with "max_size", so that we compare the *bigger* of the filepair with the break size. - It calculated a "merge_score", which was the score needed to merge it back together if nothing else wanted it. But even if it was *so* different that we would never want to merge it back, we wouldn't consider it a break! That makes no sense. So I added if (*merge_score_p > break_score) return 1; to make it clear that if we wouldn't want to merge it at the end, it was *definitely* a break. - It compared the whole "extent of damage", counting all inserts and deletes, but it based this score on the "base_size", and generated the damage score with delta_size = src_removed + literal_added; damage_score = delta_size * MAX_SCORE / base_size; but that makes no sense either, since quite often, this will result in a number that is *bigger* than MAX_SCORE! Why? Because base_size is (again) the smaller of the two files we compare, and when you start out from a small file and add a lot (or start out from a large file and remove a lot), the base_size is going to be much smaller than the damage! Again, the fix was to replace "base_size" with "max_size", at which point the damage actually becomes a sane percentage of the whole. With these changes in place, not only does "git log -B --follow" work for the case that triggered this in the first place, ie now git log -B --follow arch/x86/kernel/vmlinux_64.lds.S actually gives reasonable results. But I also wanted to verify it in general, by doing a full-history git log --stat -B -C on my kernel tree with the old code and the new code. There's some tweaking to be done, but generally, the new code generates much better results wrt breaking up files (and then finding better rename candidates). Here's a few examples of the "--stat" output: - This: include/asm-x86/Kbuild | 2 - include/asm-x86/debugreg.h | 79 +++++++++++++++++++++++++++++++++++------ include/asm-x86/debugreg_32.h | 64 --------------------------------- include/asm-x86/debugreg_64.h | 65 --------------------------------- 4 files changed, 68 insertions(+), 142 deletions(-) Becomes: include/asm-x86/Kbuild | 2 - include/asm-x86/{debugreg_64.h => debugreg.h} | 9 +++- include/asm-x86/debugreg_32.h | 64 ------------------------- 3 files changed, 7 insertions(+), 68 deletions(-) - This: include/asm-x86/bug.h | 41 +++++++++++++++++++++++++++++++++++++++-- include/asm-x86/bug_32.h | 37 ------------------------------------- include/asm-x86/bug_64.h | 34 ---------------------------------- 3 files changed, 39 insertions(+), 73 deletions(-) Becomes include/asm-x86/{bug_64.h => bug.h} | 20 +++++++++++++----- include/asm-x86/bug_32.h | 37 ----------------------------------- 2 files changed, 14 insertions(+), 43 deletions(-) Now, in some other cases, it does actually turn a rename into a real "delete+create" pair, and then the diff is usually bigger, so truth in advertizing: it doesn't always generate a nicer diff. But for what -B was meant for, I think this is a big improvement, and I suspect those cases where it generates a bigger diff are tweakable. So I think this diff fixes a real bug, but we might still want to tweak the default values and perhaps the exact rules for when a break happens. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2007-06-22Fix up "git log --follow" a bit..Libravatar Linus Torvalds1-9/+28
This fixes "git log --follow" to hopefully not leak memory any more, and also cleans it up a bit to look more like some of the other functions that use "diff_queued_diff" (by *not* using it directly as a global in the code, but by instead just taking a pointer to the diff queue and using that). As to "diff_queued_diff", I think it would be better off not as a global at all, but as being just an entry in the "struct diff_options" structure, but that's a separate issue, and there may be some subtle reason for why it's currently a global. Anyway, no real changes. Instead of having a magical first entry in the diff-queue, we now end up just keeping the diff-queue clean, and keeping our "preferred" file pairing in an internal "choice" variable. That makes it easy to switch the choice around when we find a better one. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-06-22Finally implement "git log --follow"Libravatar Linus Torvalds1-0/+59
Ok, I've really held off doing this too damn long, because I'm lazy, and I was always hoping that somebody else would do it. But no, people keep asking for it, but nobody actually did anything, so I decided I might as well bite the bullet, and instead of telling people they could add a "--follow" flag to "git log" to do what they want to do, I decided that it looks like I just have to do it for them.. The code wasn't actually that complicated, in that the diffstat for this patch literally says "70 insertions(+), 1 deletions(-)", but I will have to admit that in order to get to this fairly simple patch, you did have to know and understand the internal git diff generation machinery pretty well, and had to really be able to follow how commit generation interacts with generating patches and generating the log. So I suspect that while I was right that it wasn't that hard, I might have been expecting too much of random people - this patch does seem to be firmly in the core "Linus or Junio" territory. To make a long story short: I'm sorry for it taking so long until I just did it. I'm not going to guarantee that this works for everybody, but you really can just look at the patch, and after the appropriate appreciative noises ("Ooh, aah") over how clever I am, you can then just notice that the code itself isn't really that complicated. All the real new code is in the new "try_to_follow_renames()" function. It really isn't rocket science: we notice that the pathname we were looking at went away, so we start a full tree diff and try to see if we can instead make that pathname be a rename or a copy from some other previous pathname. And if we can, we just continue, except we show *that* particular diff, and ever after we use the _previous_ pathname. One thing to look out for: the "rename detection" is considered to be a singular event in the _linear_ "git log" output! That's what people want to do, but I just wanted to point out that this patch is *not* carrying around a "commit,pathname" kind of pair and it's *not* going to be able to notice the file coming from multiple *different* files in earlier history. IOW, if you use "git log --follow", then you get the stupid CVS/SVN kind of "files have single identities" kind of semantics, and git log will just pick the identity based on the normal move/copy heuristics _as_if_ the history could be linearized. Put another way: I think the model is broken, but given the broken model, I think this patch does just about as well as you can do. If you have merges with the same "file" having different filenames over the two branches, git will just end up picking _one_ of the pathnames at the point where the newer one goes away. It never looks at multiple pathnames in parallel. And if you understood all that, you probably didn't need it explained, and if you didn't understand the above blathering, it doesn't really mtter to you. What matters to you is that you can now do git log -p --follow builtin-rev-list.c and it will find the point where the old "rev-list.c" got renamed to "builtin-rev-list.c" and show it as such. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-03-22tree_entry_interesting(): allow it to say "everything is interesting"Libravatar Junio C Hamano1-5/+28
In addition to optimizing pathspecs that would never match, which was done earlier, this optimizes pathspecs that would always match (e.g. "arch/" while the traversal is already in "arch/i386/" hierarchy). This patch makes the worst case slightly more palatable, while improving average case. Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-03-22tree-diff: avoid strncmp()Libravatar Junio C Hamano1-23/+37
If we already know that some of the pathspecs can match later entries in the tree we are looking at, we do not have to do more expensive strncmp() upfront before comparing the length of the match pattern and the path, as a path longer than the match pattern will not match it, and a path shorter than the match pattern will match only if the path is a directory-component wise prefix of the match pattern. Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-03-22Teach tree_entry_interesting() that the tree entries are sorted.Libravatar Junio C Hamano1-6/+35
When we are looking at a tree entry with pathspecs, if all the pathspecs sort strictly earlier than the entry we are currently looking at, there is no way later entries in the same tree would match our pathspecs, because the entries are sorted. Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-03-21Initialize tree descriptors with a helper function rather than by hand.Libravatar Linus Torvalds1-10/+12
This removes slightly more lines than it adds, but the real reason for doing this is that future optimizations will require more setup of the tree descriptor, and so we want to do it in one place. Also renamed the "desc.buf" field to "desc.buffer" just to trigger compiler errors for old-style manual initializations, making sure I didn't miss anything. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Junio C Hamano <junkio@cox.net>