ab60c693a2
When line-level log is invoked with more than one disjoint line range
in the same file, and one of the commits happens to change that file
such that:
- the last line of a line range R(n) immediately preceeds the first line
modified or added by a hunk H, and
- subtracting the number of lines added by hunk H from the start and
end of the subsequent line range R(n+1) would result in a range
overlapping with line range R(n),
then git aborts with an assertion error, because those overlapping
line ranges violate the invariants:
$ git log --oneline -p
73e4e2f (HEAD -> master) Add lines 6 7 8 9 10
diff --git a/file b/file
index 572d5d9..00935f1 100644
--- a/file
+++ b/file
@@ -3,3 +3,8 @@ Line 2
Line 3
Line 4
Line 5
+Line 6
+Line 7
+Line 8
+Line 9
+Line 10
66e3561 Add lines 1 2 3 4 5
diff --git a/file b/file
new file mode 100644
index 0000000..572d5d9
--- /dev/null
+++ b/file
@@ -0,0 +1,5 @@
+Line 1
+Line 2
+Line 3
+Line 4
+Line 5
$ git log --oneline -L3,5:file -L7,8:file
git: line-log.c:73: range_set_append: Assertion `rs->nr == 0 || rs->ranges[rs->nr-1].end <= a' failed.
Aborted (core dumped)
The line-log machinery encodes line and diff ranges internally as
[start, end) pairs, i.e. include 'start' but exclude 'end', and line
numbering starts at 0 (as opposed to the -LX,Y option, where it starts
at 1, IOW the parameter -L3,5 is represented internally as { start =
2, end = 5 }).
The reason for this assertion error and some related issues is that
there are a couple of places where 'end' is mistakenly considered to
be part of the range:
- When a commit modifies an interesting path, the line-log machinery
first checks which diff range (i.e. hunk) modify any line ranges.
This is done in diff_ranges_filter_touched(), where the outer loop
iterates over the diff ranges, and in each iteration the inner
loop advances the line ranges supposedly until the current line
range ends at or after the current diff range starts, and then the
current diff and line ranges are checked for overlap.
For HEAD in the above example the first line range [2, 5) ends
just before the diff range [5, 10) starts, so the inner loop
should advance, and then the second line range [6, 8) and the diff
range should be checked for overlap.
Unfortunately, the condition of the inner loop mistakenly
considers 'end' as part of the line range, and, seeing the diff
range starting at 5 and the line range ending at 5, it doesn't
skip the first range. Consequently, the diff range and the first
line range are checked for overlap, and after that the outer loop
runs out of diff ranges, and then the processing goes on in the
false belief that this commit didn't touch any of the interesting
line ranges.
The line-log machinery later shifts the line ranges to account for
any added/removed lines in the diff ranges preceeding each line
range. This leaves the first line range intact, but attempts to
shift the second line range [6, 8) by 5 lines towards the
beginning of the file, resulting in [1, 3), triggering the
assertion error, because the two overlapping line ranges violate
the invariants.
Fix that loop condition in diff_ranges_filter_touched() to not
treat 'end' as part of the line range.
- With the above fix the assertion error is gone... but, alas, we
now get stuck in an endless loop!
This happens in range_set_difference(), where a couple of nested
loops iterate over the line and diff ranges, and a condition is
supposed to break the middle loop when the current line range ends
before the current diff range, so processing could continue with
the next line range.
For HEAD in the above example the first line range [2, 5) ends
just before the diff range [5, 10) starts, so this condition
should trigger and break the middle loop.
Unfortunately, just like in the case of the assertion error, this
conditions mistakenly considers 'end' as part of the line range,
and, seeing the line range ending at 5 and the diff range starting
at 5, it doesn't break the loop, which will then go on and on.
Fix this condition in range_set_difference() to not treat 'end' as
part of the line range.
- With the above fix the endless loop is gone... but, alas, the
output is now wrong, as it shows both line ranges for HEAD, even
though the first line range is not modified by that commit:
$ git log --oneline -L3,5:file -L7,8:file
73e4e2f (HEAD -> master) Add lines 6 7 8 9 10
diff --git a/file b/file
--- a/file
+++ b/file
@@ -3,3 +3,3 @@
Line 3
Line 4
Line 5
@@ -6,0 +7,2 @@
+Line 7
+Line 8
66e3561 Add lines 1 2 3 4 5
diff --git a/file b/file
--- /dev/null
+++ b/file
@@ -0,0 +3,3 @@
+Line 3
+Line 4
+Line 5
In dump_diff_hacky_one() a couple of nested loops are responsible
for finding and printing the modified line ranges: the big outer
loop iterates over all line ranges, and the first inner loop skips
over the diff ranges that end before the start of the current line
range. This is followed by a condition checking whether the
current diff range starts after the end of the current line range,
which, when fulfilled, continues and advances the outer loop to
the next line range.
For HEAD in the above example the first line range [2, 5) ends
just before the diff range [5, 10), so this condition should
trigger, and the outer loop should advance to the second line
range.
Unfortunately, just like in the previous cases, this condition
mistakenly considers 'end' as part of the line range, and, seeing
the first line range ending at 5 and the diff range starting at 5,
it doesn't continue to advance the outher loop, but goes on to
show the (unmodified) first line range.
Fix this condition to not treat 'end' as part of the line range,
just like in the previous cases.
After all this the command in the above example finally finishes and
produces the right output:
$ git log --oneline -L3,5:file -L7,8:file
73e4e2f (HEAD -> master) Add lines 6 7 8 9 10
diff --git a/file b/file
--- a/file
+++ b/file
@@ -6,0 +7,2 @@
+Line 7
+Line 8
66e3561 Add lines 1 2 3 4 5
diff --git a/file b/file
--- /dev/null
+++ b/file
@@ -0,0 +3,3 @@
+Line 3
+Line 4
+Line 5
Add a canned test similar to the above example, with the line ranges
adjusted to the test repository's history.
Reported-by: Evgeni Chasnovski <evgeni.chasnovski@gmail.com>
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
|
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|---|---|---|
| .github | ||
| Documentation | ||
| bin-wrappers | ||
| block-sha1 | ||
| builtin | ||
| ci | ||
| compat | ||
| contrib | ||
| ewah | ||
| git-gui | ||
| gitk-git | ||
| gitweb | ||
| mergetools | ||
| negotiator | ||
| oss-fuzz | ||
| perl | ||
| po | ||
| refs | ||
| reftable | ||
| sha1 | ||
| sha1collisiondetection@855827c583 | ||
| sha1dc | ||
| sha256 | ||
| subprojects | ||
| t | ||
| templates | ||
| trace2 | ||
| xdiff | ||
| .cirrus.yml | ||
| .clang-format | ||
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| .gitattributes | ||
| .gitignore | ||
| .gitlab-ci.yml | ||
| .gitmodules | ||
| .mailmap | ||
| .tsan-suppressions | ||
| CODE_OF_CONDUCT.md | ||
| COPYING | ||
| GIT-BUILD-OPTIONS.in | ||
| GIT-VERSION-FILE.in | ||
| GIT-VERSION-GEN | ||
| INSTALL | ||
| LGPL-2.1 | ||
| Makefile | ||
| README.md | ||
| RelNotes | ||
| SECURITY.md | ||
| abspath.c | ||
| abspath.h | ||
| aclocal.m4 | ||
| add-interactive.c | ||
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| add-patch.c | ||
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| alloc.c | ||
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| attr.c | ||
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| banned.h | ||
| base85.c | ||
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| bloom.c | ||
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| branch.c | ||
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| builtin.h | ||
| bulk-checkin.c | ||
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| bundle.c | ||
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| cache-tree.c | ||
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| cbtree.c | ||
| cbtree.h | ||
| chdir-notify.c | ||
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| check-builtins.sh | ||
| checkout.c | ||
| checkout.h | ||
| chunk-format.c | ||
| chunk-format.h | ||
| color.c | ||
| color.h | ||
| column.c | ||
| column.h | ||
| combine-diff.c | ||
| command-list.txt | ||
| commit-graph.c | ||
| commit-graph.h | ||
| commit-reach.c | ||
| commit-reach.h | ||
| commit-slab-decl.h | ||
| commit-slab-impl.h | ||
| commit-slab.h | ||
| commit.c | ||
| commit.h | ||
| common-exit.c | ||
| common-init.c | ||
| common-init.h | ||
| common-main.c | ||
| config.c | ||
| config.h | ||
| config.mak.dev | ||
| config.mak.in | ||
| config.mak.uname | ||
| configure.ac | ||
| connect.c | ||
| connect.h | ||
| connected.c | ||
| connected.h | ||
| convert.c | ||
| convert.h | ||
| copy.c | ||
| copy.h | ||
| credential.c | ||
| credential.h | ||
| csum-file.c | ||
| csum-file.h | ||
| ctype.c | ||
| daemon.c | ||
| date.c | ||
| date.h | ||
| decorate.c | ||
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| delta-islands.c | ||
| delta-islands.h | ||
| delta.h | ||
| detect-compiler | ||
| diagnose.c | ||
| diagnose.h | ||
| diff-delta.c | ||
| diff-lib.c | ||
| diff-merges.c | ||
| diff-merges.h | ||
| diff-no-index.c | ||
| diff.c | ||
| diff.h | ||
| diffcore-break.c | ||
| diffcore-delta.c | ||
| diffcore-order.c | ||
| diffcore-pickaxe.c | ||
| diffcore-rename.c | ||
| diffcore-rotate.c | ||
| diffcore.h | ||
| dir-iterator.c | ||
| dir-iterator.h | ||
| dir.c | ||
| dir.h | ||
| editor.c | ||
| editor.h | ||
| entry.c | ||
| entry.h | ||
| environment.c | ||
| environment.h | ||
| exec-cmd.c | ||
| exec-cmd.h | ||
| fetch-negotiator.c | ||
| fetch-negotiator.h | ||
| fetch-pack.c | ||
| fetch-pack.h | ||
| fmt-merge-msg.c | ||
| fmt-merge-msg.h | ||
| fsck.c | ||
| fsck.h | ||
| fsmonitor--daemon.h | ||
| fsmonitor-ipc.c | ||
| fsmonitor-ipc.h | ||
| fsmonitor-ll.h | ||
| fsmonitor-path-utils.h | ||
| fsmonitor-settings.c | ||
| fsmonitor-settings.h | ||
| fsmonitor.c | ||
| fsmonitor.h | ||
| generate-cmdlist.sh | ||
| generate-configlist.sh | ||
| generate-hooklist.sh | ||
| generate-perl.sh | ||
| generate-python.sh | ||
| generate-script.sh | ||
| gettext.c | ||
| gettext.h | ||
| git-archimport.perl | ||
| git-compat-util.h | ||
| git-curl-compat.h | ||
| git-cvsexportcommit.perl | ||
| git-cvsimport.perl | ||
| git-cvsserver.perl | ||
| git-difftool--helper.sh | ||
| git-filter-branch.sh | ||
| git-instaweb.sh | ||
| git-merge-octopus.sh | ||
| git-merge-one-file.sh | ||
| git-merge-resolve.sh | ||
| git-mergetool--lib.sh | ||
| git-mergetool.sh | ||
| git-p4.py | ||
| git-quiltimport.sh | ||
| git-request-pull.sh | ||
| git-send-email.perl | ||
| git-sh-i18n.sh | ||
| git-sh-setup.sh | ||
| git-submodule.sh | ||
| git-svn.perl | ||
| git-web--browse.sh | ||
| git-zlib.c | ||
| git-zlib.h | ||
| git.c | ||
| git.rc.in | ||
| gpg-interface.c | ||
| gpg-interface.h | ||
| graph.c | ||
| graph.h | ||
| grep.c | ||
| grep.h | ||
| hash-lookup.c | ||
| hash-lookup.h | ||
| hash.h | ||
| hashmap.c | ||
| hashmap.h | ||
| help.c | ||
| help.h | ||
| hex-ll.c | ||
| hex-ll.h | ||
| hex.c | ||
| hex.h | ||
| hook.c | ||
| hook.h | ||
| http-backend.c | ||
| http-fetch.c | ||
| http-push.c | ||
| http-walker.c | ||
| http.c | ||
| http.h | ||
| ident.c | ||
| ident.h | ||
| imap-send.c | ||
| iterator.h | ||
| json-writer.c | ||
| json-writer.h | ||
| khash.h | ||
| kwset.c | ||
| kwset.h | ||
| levenshtein.c | ||
| levenshtein.h | ||
| line-log.c | ||
| line-log.h | ||
| line-range.c | ||
| line-range.h | ||
| linear-assignment.c | ||
| linear-assignment.h | ||
| list-objects-filter-options.c | ||
| list-objects-filter-options.h | ||
| list-objects-filter.c | ||
| list-objects-filter.h | ||
| list-objects.c | ||
| list-objects.h | ||
| list.h | ||
| lockfile.c | ||
| lockfile.h | ||
| log-tree.c | ||
| log-tree.h | ||
| loose.c | ||
| loose.h | ||
| ls-refs.c | ||
| ls-refs.h | ||
| mailinfo.c | ||
| mailinfo.h | ||
| mailmap.c | ||
| mailmap.h | ||
| match-trees.c | ||
| match-trees.h | ||
| mem-pool.c | ||
| mem-pool.h | ||
| merge-blobs.c | ||
| merge-blobs.h | ||
| merge-ll.c | ||
| merge-ll.h | ||
| merge-ort-wrappers.c | ||
| merge-ort-wrappers.h | ||
| merge-ort.c | ||
| merge-ort.h | ||
| merge-recursive.c | ||
| merge-recursive.h | ||
| merge.c | ||
| merge.h | ||
| mergesort.h | ||
| meson.build | ||
| meson_options.txt | ||
| midx-write.c | ||
| midx.c | ||
| midx.h | ||
| name-hash.c | ||
| name-hash.h | ||
| notes-cache.c | ||
| notes-cache.h | ||
| notes-merge.c | ||
| notes-merge.h | ||
| notes-utils.c | ||
| notes-utils.h | ||
| notes.c | ||
| notes.h | ||
| object-file-convert.c | ||
| object-file-convert.h | ||
| object-file.c | ||
| object-file.h | ||
| object-name.c | ||
| object-name.h | ||
| object-store-ll.h | ||
| object-store.h | ||
| object.c | ||
| object.h | ||
| oid-array.c | ||
| oid-array.h | ||
| oidmap.c | ||
| oidmap.h | ||
| oidset.c | ||
| oidset.h | ||
| oidtree.c | ||
| oidtree.h | ||
| pack-bitmap-write.c | ||
| pack-bitmap.c | ||
| pack-bitmap.h | ||
| pack-check.c | ||
| pack-mtimes.c | ||
| pack-mtimes.h | ||
| pack-objects.c | ||
| pack-objects.h | ||
| pack-revindex.c | ||
| pack-revindex.h | ||
| pack-write.c | ||
| pack.h | ||
| packfile.c | ||
| packfile.h | ||
| pager.c | ||
| pager.h | ||
| parallel-checkout.c | ||
| parallel-checkout.h | ||
| parse-options-cb.c | ||
| parse-options.c | ||
| parse-options.h | ||
| parse.c | ||
| parse.h | ||
| patch-delta.c | ||
| patch-ids.c | ||
| patch-ids.h | ||
| path-walk.c | ||
| path-walk.h | ||
| path.c | ||
| path.h | ||
| pathspec.c | ||
| pathspec.h | ||
| pkt-line.c | ||
| pkt-line.h | ||
| preload-index.c | ||
| preload-index.h | ||
| pretty.c | ||
| pretty.h | ||
| prio-queue.c | ||
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| progress.h | ||
| promisor-remote.c | ||
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| prompt.c | ||
| prompt.h | ||
| protocol-caps.c | ||
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| protocol.h | ||
| prune-packed.c | ||
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| quote.c | ||
| quote.h | ||
| range-diff.c | ||
| range-diff.h | ||
| reachable.c | ||
| reachable.h | ||
| read-cache-ll.h | ||
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| read-cache.h | ||
| rebase-interactive.c | ||
| rebase-interactive.h | ||
| rebase.c | ||
| rebase.h | ||
| ref-filter.c | ||
| ref-filter.h | ||
| reflog-walk.c | ||
| reflog-walk.h | ||
| reflog.c | ||
| reflog.h | ||
| refs.c | ||
| refs.h | ||
| refspec.c | ||
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| remote.h | ||
| replace-object.c | ||
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| repo-settings.c | ||
| repo-settings.h | ||
| repository.c | ||
| repository.h | ||
| rerere.c | ||
| rerere.h | ||
| reset.c | ||
| reset.h | ||
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| revision.c | ||
| revision.h | ||
| run-command.c | ||
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| sane-ctype.h | ||
| scalar.c | ||
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| sequencer.c | ||
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| serve.c | ||
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| setup.c | ||
| setup.h | ||
| sh-i18n--envsubst.c | ||
| sha1dc_git.c | ||
| sha1dc_git.h | ||
| shallow.c | ||
| shallow.h | ||
| shared.mak | ||
| shell.c | ||
| shortlog.h | ||
| sideband.c | ||
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| sigchain.c | ||
| sigchain.h | ||
| simple-ipc.h | ||
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| unimplemented.sh | ||
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| versioncmp.c | ||
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| xdiff-interface.c | ||
| xdiff-interface.h | ||
README.md
Git - fast, scalable, distributed revision control system
Git is a fast, scalable, distributed revision control system with an unusually rich command set that provides both high-level operations and full access to internals.
Git is an Open Source project covered by the GNU General Public License version 2 (some parts of it are under different licenses, compatible with the GPLv2). It was originally written by Linus Torvalds with help of a group of hackers around the net.
Please read the file INSTALL for installation instructions.
Many Git online resources are accessible from https://git-scm.com/ including full documentation and Git related tools.
See Documentation/gittutorial.adoc to get started, then see
Documentation/giteveryday.adoc for a useful minimum set of commands, and
Documentation/git-<commandname>.adoc for documentation of each command.
If git has been correctly installed, then the tutorial can also be
read with man gittutorial or git help tutorial, and the
documentation of each command with man git-<commandname> or git help <commandname>.
CVS users may also want to read Documentation/gitcvs-migration.adoc
(man gitcvs-migration or git help cvs-migration if git is
installed).
The user discussion and development of Git take place on the Git mailing list -- everyone is welcome to post bug reports, feature requests, comments and patches to git@vger.kernel.org (read Documentation/SubmittingPatches for instructions on patch submission and Documentation/CodingGuidelines).
Those wishing to help with error message, usage and informational message
string translations (localization l10) should see po/README.md
(a po file is a Portable Object file that holds the translations).
To subscribe to the list, send an email to git+subscribe@vger.kernel.org (see https://subspace.kernel.org/subscribing.html for details). The mailing list archives are available at https://lore.kernel.org/git/, https://marc.info/?l=git and other archival sites.
Issues which are security relevant should be disclosed privately to the Git Security mailing list git-security@googlegroups.com.
The maintainer frequently sends the "What's cooking" reports that list the current status of various development topics to the mailing list. The discussion following them give a good reference for project status, development direction and remaining tasks.
The name "git" was given by Linus Torvalds when he wrote the very first version. He described the tool as "the stupid content tracker" and the name as (depending on your mood):
- random three-letter combination that is pronounceable, and not actually used by any common UNIX command. The fact that it is a mispronunciation of "get" may or may not be relevant.
- stupid. contemptible and despicable. simple. Take your pick from the dictionary of slang.
- "global information tracker": you're in a good mood, and it actually works for you. Angels sing, and a light suddenly fills the room.
- "goddamn idiotic truckload of sh*t": when it breaks