Fixes a long-standing corner case bug around directory renames in
the merge-ort strategy.
* en/merge-dual-dir-renames-fix:
merge-ort: fix issue with dual rename and add/add conflict
merge-ort: shuffle the computation and cleanup of potential collisions
merge-ort: make a separate function for freeing struct collisions
merge-ort: small cleanups of check_for_directory_rename
t6423: add tests of dual directory rename plus add/add conflict
There is code in both merge-recursive and merge-ort for avoiding doubly
transitive renames (i.e. one side renames directory A/ -> B/, and the
other side renames directory B/ -> C/), because this combination would
otherwise make a mess for new files added to A/ on the first side and
wondering which directory they end up in -- especially if there were
even more renames such as the first side renaming C/ -> D/. In such
cases, it just turns "off" directory rename detection for the higher
order transitive cases.
The testcases added in t6423 a couple commits ago are slightly different
but similar in principle. They involve a similar case of paired
renaming but instead of A/ -> B/ and B/ -> C/, the second side renames
a leading directory of B/ to C/. And both sides add a new file
somewhere under the directory that the other side will rename. While
the new files added start within different directories and thus could
logically end up within different directories, it is weird for a file
on one side to end up where the other one started and not move along
with it. So, let's just turn off directory rename detection in this
case as well.
Another way to look at this is that if the source name involved in a
directory rename on one side is the target name of a directory rename
operation for a file from the other side, then we avoid the doubly
transitive rename. (More concretely, if a directory rename on side D
wants to rename a file on side E from OLD_NAME -> NEW_NAME, and side D
already had a file named NEW_NAME, and a directory rename on side E
wants to rename side D's NEW_NAME -> NEWER_NAME, then we turn off the
directory rename detection for NEW_NAME to prevent the
NEW_NAME -> NEWER_NAME rename, and instead end up with an add/add
conflict on NEW_NAME.)
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Run compute_collisions() for renames on both sides of history before
any calls to collect_renames(), and do not free the computed collisions
until after both calls to collect_renames(). This is just a code
reorganization at this point that doesn't make sense on its own, but
will permit us to use the computed collision info from both sides
within each call to collect_renames() in a subsequent commit.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit makes no functional changes, it's just some code movement in
preparation for later changes.
Signed-off-by: Elijah Newren <newren@palantir.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
No functional changes, just some preparatory cleanups.
Suggested-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Elijah Newren <newren@palantir.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
With the new `detailed` parameter, a new mode can be triggered when
displaying the merge messages: The `detailed` mode prints NUL-delimited
fields of the following form:
<path-count> NUL <path>... NUL <conflict-type> NUL <message>
The `<path-count>` field determines how many `<path>` fields there are.
The intention of this mode is to support server-side operations, where
worktree-less merges can lead to conflicts and depending on the type
and/or path count, the caller might know how to handle said conflict.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It is all fine and dandy for a regular Git command that is intended to
be run interactively to produce a bunch of messages upon an error.
However, in `merge-ort`'s case, we want to call the command e.g. in
server-side software, where the actual error messages are not quite as
interesting as machine-readable, immutable terms that describe the exact
nature of any given conflict.
With this patch, the `merge-ort` machinery records the exact type (as
specified via an `enum` value) as well as the involved path(s) together
with the conflict's message.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This allows us once again to get away with less data copying.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
To prepare for using the `merge-ort` machinery in server operations, we
cannot simply produce a free-form string that combines a variable-length
list of messages.
Instead, we need to list them one by one. The natural fit for this is a
`string_list`.
We will subsequently add even more information in the `util` attribute
of the string list items.
Based-on-a-patch-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There was one case in merge-ort that would call path_msg() multiple
times for the same logical conflict, and it was in order to give advice
about how to resolve a conflict. This advice does not make as much
sense with remerge-diff, or with merge-tree being invoked by a GitHub
GUI for resolution of messages, and is making it hard to provide
which-logical-conflict-affects-which-paths information in a machine
parseable way to a higher level caller of merge-tree. Let's simply
remove this informational message.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
After a merge, this function allows the user to extract the same
information that would be printed by `ls-files -u`, which means
files with their mode, oid, and stage.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This patch includes no new code; it simply moves a bunch of lines into a
new function. As such, there are no functional changes. This is just a
preparatory step to allow the printed messages to be handled differently
by other callers, such as in `git merge-tree --write-tree`.
(Patch best viewed with
--color-moved --color-moved-ws=allow-indentation-change
to see that it is a simple code movement.)
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Plug the memory leaks from the trickiest API of all, the revision
walker.
* ab/plug-leak-in-revisions: (27 commits)
revisions API: add a TODO for diff_free(&revs->diffopt)
revisions API: have release_revisions() release "topo_walk_info"
revisions API: have release_revisions() release "date_mode"
revisions API: call diff_free(&revs->pruning) in revisions_release()
revisions API: release "reflog_info" in release revisions()
revisions API: clear "boundary_commits" in release_revisions()
revisions API: have release_revisions() release "prune_data"
revisions API: have release_revisions() release "grep_filter"
revisions API: have release_revisions() release "filter"
revisions API: have release_revisions() release "cmdline"
revisions API: have release_revisions() release "mailmap"
revisions API: have release_revisions() release "commits"
revisions API users: use release_revisions() for "prune_data" users
revisions API users: use release_revisions() with UNLEAK()
revisions API users: use release_revisions() in builtin/log.c
revisions API users: use release_revisions() in http-push.c
revisions API users: add "goto cleanup" for release_revisions()
stash: always have the owner of "stash_info" free it
revisions API users: use release_revisions() needing REV_INFO_INIT
revision.[ch]: document and move code declared around "init"
...
Introduce and apply coccinelle rule to discourage an explicit
comparison between a pointer and NULL, and applies the clean-up to
the maintenance track.
* ep/maint-equals-null-cocci:
tree-wide: apply equals-null.cocci
tree-wide: apply equals-null.cocci
contrib/coccinnelle: add equals-null.cocci
Add a release_revisions() to various users of "struct rev_list" in
those straightforward cases where we only need to add the
release_revisions() call to the end of a block, and don't need to
e.g. refactor anything to use a "goto cleanup" pattern.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Count string_list items in size_t, not "unsigned int".
* ab/string-list-count-in-size-t:
string-list API: change "nr" and "alloc" to "size_t"
gettext API users: don't explicitly cast ngettext()'s "n"
Object-file API shuffling.
* ab/object-file-api-updates:
object-file API: pass an enum to read_object_with_reference()
object-file.c: add a literal version of write_object_file_prepare()
object-file API: have hash_object_file() take "enum object_type"
object API: rename hash_object_file_literally() to write_*()
object-file API: split up and simplify check_object_signature()
object API users + docs: check <0, not !0 with check_object_signature()
object API docs: move check_object_signature() docs to cache.h
object API: correct "buf" v.s. "map" mismatch in *.c and *.h
object-file API: have write_object_file() take "enum object_type"
object-file API: add a format_object_header() function
object-file API: return "void", not "int" from hash_object_file()
object-file.c: split up declaration of unrelated variables
Align the level of verbose output from the ort backend during inner
merge to that of the recursive backend.
* en/merge-ort-align-verbosity-with-recursive:
merge-ort: exclude messages from inner merges by default
Change the "nr" and "alloc" members of "struct string_list" to use
"size_t" instead of "nr". On some platforms the size of an "unsigned
int" will be smaller than a "size_t", e.g. a 32 bit unsigned v.s. 64
bit unsigned. As "struct string_list" is a generic API we use in a lot
of places this might cause overflows.
As one example: code in "refs.c" keeps track of the number of refs
with a "size_t", and auxiliary code in builtin/remote.c in
get_ref_states() appends those to a "struct string_list".
While we're at it split the "nr" and "alloc" in string-list.h across
two lines, which is the case for most such struct member
declarations (e.g. in "strbuf.h" and "strvec.h").
Changing e.g. "int i" to "size_t i" in run_and_feed_hook() isn't
strictly necessary, and there are a lot more cases where we'll use a
local "int", "unsigned int" etc. variable derived from the "nr" in the
"struct string_list". But in that case as well as
add_wrapped_shortlog_msg() in builtin/shortlog.c we need to adjust the
printf format referring to "nr" anyway, so let's also change the other
variables referring to it.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
merge-recursive would only report messages from inner merges when the
GIT_MERGE_VERBOSITY was set to 5. Do the same for merge-ort.
Note that somewhat reverts 0d83d8240d ("merge-ort: mark conflict/warning
messages from inner merges as omittable", 2022-02-02) based on two
facts:
* This commit basically removes the showing of messages from inner
merges as well, at least by default. The only difference is that
users can request to get them back by turning up the verbosity.
* Messages from inner merges are specially annotated since 4a3d86e1bb
("merge-ort: make informational messages from recursive merges
clearer", 2022-02-17). The ability to distinguish them from outer
merge comments make them less problematic to include, and easier
for humans to parse.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change the write_object_file() function to take an "enum object_type"
instead of a "const char *type". Its callers either passed
{commit,tree,blob,tag}_type and can pass the corresponding OBJ_* type
instead, or were hardcoding strings like "blob".
This avoids the back & forth fragility where the callers of
write_object_file() would have the enum type, and convert it
themselves via type_name(). We do have to now do that conversion
ourselves before calling write_object_file_prepare(), but those
codepaths will be similarly adjusted in subsequent commits.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The struct strmap paths member of merge_options_internal is perhaps the
most central data structure to all of merge-ort. Because all the paths
involved in the merge need to be kept until the merge is complete, this
"paths" data structure traditionally took responsibility for owning all
the allocated paths. When the merge is over, those paths were free()d
as part of free()ing this strmap.
In commit 6697ee01b5 (merge-ort: switch our strmaps over to using
memory pools, 2021-07-30), we changed the allocations for pathnames to
come from a memory pool. That meant the ownership changed slightly;
there were no individual free() calls to make, instead the memory pool
owned all those paths and they were free()d all at once.
Unfortunately unique_path() was written presuming the pre-memory-pool
model, and allocated a path on the heap and left it in the strmap for
later free()ing. Modify it to return a path allocated from the memory
pool instead.
Note that there's one instance -- in record_conflicted_index_entries()
-- where the returned string from unique_path() was only used very
temporarily and thus had been immediately free()'d. This codepath was
associated with an ugly skip-worktree workaround that has since been
better fixed by the in-flight en/present-despite-skipped topic. This
workaround probably makes sense to excise once that topic merges down,
but for now, just remove the immediate free() and allow the returned
string to be free()d when the memory pool is released.
This fixes the following memory leak as reported by valgrind:
==PID== 65 bytes in 1 blocks are definitely lost in loss record 79 of 134
==PID== at 0xADDRESS: malloc
==PID== by 0xADDRESS: realloc
==PID== by 0xADDRESS: xrealloc (wrapper.c:126)
==PID== by 0xADDRESS: strbuf_grow (strbuf.c:98)
==PID== by 0xADDRESS: strbuf_vaddf (strbuf.c:394)
==PID== by 0xADDRESS: strbuf_addf (strbuf.c:335)
==PID== by 0xADDRESS: unique_path (merge-ort.c:733)
==PID== by 0xADDRESS: process_entry (merge-ort.c:3678)
==PID== by 0xADDRESS: process_entries (merge-ort.c:4037)
==PID== by 0xADDRESS: merge_ort_nonrecursive_internal (merge-ort.c:4621)
==PID== by 0xADDRESS: merge_ort_internal (merge-ort.c:4709)
==PID== by 0xADDRESS: merge_incore_recursive (merge-ort.c:4760)
==PID== by 0xADDRESS: merge_ort_recursive (merge-ort-wrappers.c:57)
==PID== by 0xADDRESS: try_merge_strategy (merge.c:753)
Reported-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
detect_and_process_renames() detects renames on both sides of history
and then combines these into a single diff_queue_struct. The combined
diff_queue_struct needs to be able to hold the renames found on either
side, and since it knows the (maximum) size it needs, it pre-emptively
grows the array to the appropriate size:
ALLOC_GROW(combined.queue,
renames->pairs[1].nr + renames->pairs[2].nr,
combined.alloc);
It then collects the items from each side:
collect_renames(opt, &combined, MERGE_SIDE1, ...)
collect_renames(opt, &combined, MERGE_SIDE2, ...)
Note, though, that collect_renames() sometimes determines that some
pairs are unnecessary and does not include them in the combined array.
When it is done, detect_and_process_renames() frees this memory:
if (combined.nr) {
...
free(combined.queue);
}
The problem is that sometimes even when there are pairs, none of them
are necessary. Instead of checking combined.nr, just remove the
if-check; free() knows to skip NULL pointers. This change fixes the
following memory leak, as reported by valgrind:
==PID== 192 bytes in 1 blocks are definitely lost in loss record 107 of 134
==PID== at 0xADDRESS: malloc
==PID== by 0xADDRESS: realloc
==PID== by 0xADDRESS: xrealloc (wrapper.c:126)
==PID== by 0xADDRESS: detect_and_process_renames (merge-ort.c:3134)
==PID== by 0xADDRESS: merge_ort_nonrecursive_internal (merge-ort.c:4610)
==PID== by 0xADDRESS: merge_ort_internal (merge-ort.c:4709)
==PID== by 0xADDRESS: merge_incore_recursive (merge-ort.c:4760)
==PID== by 0xADDRESS: merge_ort_recursive (merge-ort-wrappers.c:57)
==PID== by 0xADDRESS: try_merge_strategy (merge.c:753)
==PID== by 0xADDRESS: cmd_merge (merge.c:1676)
==PID== by 0xADDRESS: run_builtin (git.c:461)
==PID== by 0xADDRESS: handle_builtin (git.c:713)
==PID== by 0xADDRESS: run_argv (git.c:780)
==PID== by 0xADDRESS: cmd_main (git.c:911)
==PID== by 0xADDRESS: main (common-main.c:52)
Reported-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This is another simple change with a long explanation...
merge-recursive and merge-ort are both based on the same recursive idea:
if there is more than one merge base, merge the merge bases (which may
require first merging the merge bases of the merges bases, etc.). The
depth of the inner merge is recorded via a variable called "call_depth",
which we'll bring up again later. Naturally, the inner merges
themselves can have conflicts and various messages generated about those
files.
merge-recursive immediately prints to stdout as it goes, at the risk of
printing multiple conflict notices for the same path separated far apart
from each other with many intervenining conflict notices for other paths
between them. And this is true even if there are no inner merges
involved. An example of this was given in [1] and apparently caused
some confusion:
CONFLICT (rename/add): Rename A->B in HEAD. B added in otherbranch
...dozens of conflicts for OTHER paths...
CONFLICT (content): Merge conflicts in B
In contrast, merge-ort collects messages and stores them by path so that
it can print them grouped by path. Thus, the same case handled by
merge-ort would have output of the form:
CONFLICT (rename/add): Rename A->B in HEAD. B added in otherbranch
CONFLICT (content): Merge conflicts in B
...dozens of conflicts for OTHER paths...
This is generally helpful, but does make a separate bug more
problematic. In particular, while merge-recursive might report the
following for a recursive merge:
Auto-merging dir.c
Auto-merging midx.c
CONFLICT (content): Merge conflict in midx.c
Auto-merging diff.c
Auto-merging dir.c
CONFLICT (content): Merge conflict in dir.c
merge-ort would instead report:
Auto-merging diff.c
Auto-merging dir.c
Auto-merging dir.c
CONFLICT (content): Merge conflict in dir.c
Auto-merging midx.c
CONFLICT (content): Merge conflict in midx.c
The fact that messages for the same file are together is probably
helpful in general, but with the indentation missing for the inner
merge it unfortunately serves to confuse. This probably would lead
users to wonder:
* Why is Git reporting that "dir.c" is being merged twice?
* If midx.c has conflicts, why do I not see any when I open up the
file and why are no conflicts shown in the index?
Fix this output confusion by changing the output to clearly
differentiate the messages for outer merges from the ones for inner
merges, changing the above output from merge-ort to:
Auto-merging diff.c
From inner merge: Auto-merging dir.c
Auto-merging dir.c
CONFLICT (content): Merge conflict in dir.c
From inner merge: Auto-merging midx.c
From inner merge: CONFLICT (content): Merge conflict in midx.c
(Note: the number of spaces after the 'From inner merge:' is
2*call_depth).
One other thing to note here, that I didn't notice until typing up this
commit message, is that merge-recursive does not print any messages from
the inner merges by default; the extra verbosity has to be requested.
merge-ort currently has no verbosity controls and always prints these.
We may also want to change that, but for now, just make the output
clearer with these extra markings and indentation.
[1] https://lore.kernel.org/git/CAGyf7-He4in8JWUh9dpAwvoPkQz9hr8nCBpxOxhZEd8+jtqTpg@mail.gmail.com/
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git log --remerge-diff" shows the difference from mechanical merge
result and the result that is actually recorded in a merge commit.
* en/remerge-diff:
diff-merges: avoid history simplifications when diffing merges
merge-ort: mark conflict/warning messages from inner merges as omittable
show, log: include conflict/warning messages in --remerge-diff headers
diff: add ability to insert additional headers for paths
merge-ort: format messages slightly different for use in headers
merge-ort: mark a few more conflict messages as omittable
merge-ort: capture and print ll-merge warnings in our preferred fashion
ll-merge: make callers responsible for showing warnings
log: clean unneeded objects during `log --remerge-diff`
show, log: provide a --remerge-diff capability
The merge-ort misbehaved when merge.renameLimit configuration is
set too low and failed to find all renames.
* en/merge-ort-restart-optim-fix:
merge-ort: avoid assuming all renames detected
A recursive merge involves merging the merge bases of the two branches
being merged. Such an inner merge can itself generate conflict notices.
While such notices may be useful when initially trying to create a
merge, they seem to just be noise when investigating merges later with
--remerge-diff. (Especially when both sides of the outer merge resolved
the conflict the same way leading to no overall conflict.) Remove them.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Conflicts such as modify/delete, rename/rename, or file/directory are
not representable via content conflict markers, and the normal output
messages notifying users about these were dropped with --remerge-diff.
While we don't want these messages randomly shown before the commit
and diff headers, we do want them to still be shown; include them as
part of the diff headers instead.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When users run
git show --remerge-diff $MERGE_COMMIT
or
git log -p --remerge-diff ...
stdout is not an appropriate location to dump conflict messages, but we
do want to provide them to users. We will include them in the diff
headers instead...but for that to work, we need for any multiline
messages to replace newlines with both a newline and a space. Add a new
flag to signal when we want these messages modified in such a fashion,
and use it in path_msg() to modify these messages this way. Also, allow
a special prefix to be specified for these headers.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
path_msg() has the ability to mark messages as omittable, designed for
remerge-diff where we'll instead be showing conflict messages as diff
headers for a subsequent diff. While all these messages are very useful
when trying to create a merge initially, early use with the
--remerge-diff feature (the only user of this omittable conflict message
capability), suggests that the particular messages marked in this commit
are just noise when trying to see what changes users made to create a
merge commit. Mark them as omittable.
Note that there were already a few messages marked as omittable in
merge-ort when doing a remerge-diff, because the development of
--remerge-diff preceded the upstreaming of merge-ort and I was trying to
ensure merge-ort could handle all the necessary requirements. See
commit c5a6f65527 ("merge-ort: add modify/delete handling and delayed
output processing", 2020-12-03) for the initial details. For some
examples of already-marked-as-omittable messages, see either
"Auto-merging <path>" or some of the submodule update hints. This
commit just adds two more messages that should also be omittable.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead of immediately printing ll-merge warnings to stderr, we save
them in our output strbuf. Besides allowing us to move these warnings
to a special file for --remerge-diff, this has two other benefits for
regular merges done by merge-ort:
* The deferral of messages ensures we can print all messages about
any given path together (merge-recursive was known to sometimes
intersperse messages about other paths, particularly when renames
were involved).
* The deferral of messages means we can avoid printing spurious
conflict messages when we just end up aborting due to local user
modifications in the way. (In contrast to merge-recursive.c which
prematurely checks for local modifications in the way via
unpack_trees() and gets the check wrong both in terms of false
positives and false negatives relative to renames, merge-ort does
not perform the local modifications in the way check until the
checkout() step after the full merge has been computed.)
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since some callers may want to send warning messages to somewhere other
than stdout/stderr, stop printing "warning: Cannot merge binary files"
from ll-merge and instead modify the return status of ll_merge() to
indicate when a merge of binary files has occurred. Message printing
probably does not belong in a "low-level merge" anyway.
This commit continues printing the message as-is, just from the callers
instead of within ll_merge(). Future changes will start handling the
message differently in the merge-ort codepath.
There was one special case here: the callers in rerere.c do NOT check
for and print such a message; since those code paths explicitly skip
over binary files, there is no reason to check for a return status of
LL_MERGE_BINARY_CONFLICT or print the related message.
Note that my methodology included first modifying ll_merge() to return
a struct, so that the compiler would catch all the callers for me and
ensure I had modified all of them. After modifying all of them, I then
changed the struct to an enum.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The documentation for merge_incore_recursive(), modelled after
merge_recursive(), notes that
merge_bases will be consumed (emptied) so make a copy if you need it
However, in merge_ort_internal() (which merge_incore_recursive() calls),
it runs
merged_merge_bases = pop_commit(&merge_bases);
...
for (iter = merge_bases; iter; iter = iter->next) {
...
}
In other words, it only consumes the *first* entry of merge_bases, and
the rest it iterates through. If it iterated through all of them, the
caller could be responsible for free'ing the memory. If it consumed all
of them, the current documentation would be correct and the callers
would need to do nothing. The current middle ground makes it impossible
for callers to avoid memory leaks, since any attempt to use the
merge_bases it passes in would result in a use-after-free.
It turns out this part of the code was copied from merge-recursive.c,
which has had the same bug for 15.5 years. However, since we are trying
to keep merge-recursive.c stable as we sunset it, let's just fix the
leak in in merge_ort_internal() by having it actually consume all the
elements of the merge_bases commit_list.
Testing this commit against t6404 (the first testcase specifically
about recursive merges) under valgrind shows that this patch fixes
the following leak:
32 (16 direct, 16 indirect) bytes in 1 blocks are definitely lost \
in loss record 49 of 126
at 0x484086F: malloc (vg_replace_malloc.c:380)
by 0x69FFEB: do_xmalloc (wrapper.c:41)
by 0x6A0073: xmalloc (wrapper.c:62)
by 0x52A72D: commit_list_insert (commit.c:556)
by 0x47EC86: try_merge_strategy (merge.c:751)
by 0x48143B: cmd_merge (merge.c:1679)
by 0x40686E: run_builtin (git.c:464)
by 0x406C51: handle_builtin (git.c:716)
by 0x406E96: run_argv (git.c:783)
by 0x40730A: cmd_main (git.c:914)
by 0x4E7DFA: main (common-main.c:56)
Reported-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In commit 8b09a900a1 ("merge-ort: restart merge with cached renames to
reduce process entry cost", 2021-07-16), we noted that in the merge-ort
steps of
collect_merge_info()
detect_and_process_renames()
process_entries()
that process_entries() was expensive, and we could often make it cheaper
by changing this to
collect_merge_info()
detect_and_process_renames()
<cache all the renames, and restart>
collect_merge_info()
detect_and_process_renames()
process_entries()
because the second collect_merge_info() would be cheaper (we could avoid
traversing into some directories), the second
detect_and_process_renames() would be free since we had already detected
all renames, and then process_entries() has far fewer entries to handle.
However, this was built on the assumption that the first
detect_and_process_renames() actually detected all potential renames.
If someone has merge.renameLimit set to some small value, that
assumption is violated which manifests later with the following message:
$ git -c merge.renameLimit=1 rebase upstream
...
git: merge-ort.c:546: clear_or_reinit_internal_opts: Assertion
`renames->cached_pairs_valid_side == 0' failed.
Turn off this cache-renames-and-restart whenever we cannot detect all
renames, and add a testcase that would have caught this problem.
Reported-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Tested-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Ever since commit a492d5331c ("merge-ort: ensure we consult df_conflict
and path_conflicts", 2021-06-30), when renormalization is active AND a
file is involved in a rename/delete conflict BUT the file is unmodified
(either before or after renormalization), merge-ort was running into an
assertion failure. Prior to that commit (or if assertions were compiled
out), merge-ort would mis-merge instead, ignoring the rename/delete
conflict and just deleting the file.
Remove the assertions, fix the code appropriately, leave some good
comments in the code, and add a testcase for this situation.
Reported-by: Ralf Thielow <ralf.thielow@gmail.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Follow through the work to use the repo interface to access
submodule objects in-process, instead of abusing the alternate
object database interface.
* jt/no-abuse-alternate-odb-for-submodules:
submodule: trace adding submodule ODB as alternate
submodule: pass repo to check_has_commit()
object-file: only register submodule ODB if needed
merge-{ort,recursive}: remove add_submodule_odb()
refs: peeling non-the_repository iterators is BUG
refs: teach arbitrary repo support to iterators
refs: plumb repo into ref stores
Various fixes in code paths that move untracked files away to make room.
* en/removing-untracked-fixes:
Documentation: call out commands that nuke untracked files/directories
Comment important codepaths regarding nuking untracked files/dirs
unpack-trees: avoid nuking untracked dir in way of locally deleted file
unpack-trees: avoid nuking untracked dir in way of unmerged file
Change unpack_trees' 'reset' flag into an enum
Remove ignored files by default when they are in the way
unpack-trees: make dir an internal-only struct
unpack-trees: introduce preserve_ignored to unpack_trees_options
read-tree, merge-recursive: overwrite ignored files by default
checkout, read-tree: fix leak of unpack_trees_options.dir
t2500: add various tests for nuking untracked files
After the parent commit and some of its ancestors, the only place
commits are being accessed through alternates is in the user-facing
message formatting code. Fix those, and remove the add_submodule_odb()
calls.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
More code paths that use the hack to add submodule's object
database to the set of alternate object store have been cleaned up.
* jt/add-submodule-odb-clean-up:
revision: remove "submodule" from opt struct
repository: support unabsorbed in repo_submodule_init
submodule: remove unnecessary unabsorbed fallback
Change several commands to remove ignored files by default when they are
in the way. Since some commands (checkout, merge) take a
--no-overwrite-ignore option to allow the user to configure this, and it
may make sense to add that option to more commands (and in the case of
merge, actually plumb that configuration option through to more of the
backends than just the fast-forwarding special case), add little
comments about where such flags would be used.
Incidentally, this fixes a test failure in t7112.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Currently, every caller of unpack_trees() that wants to ensure ignored
files are overwritten by default needs to:
* allocate unpack_trees_options.dir
* flip the DIR_SHOW_IGNORED flag in unpack_trees_options.dir->flags
* call setup_standard_excludes
AND then after the call to unpack_trees() needs to
* call dir_clear()
* deallocate unpack_trees_options.dir
That's a fair amount of boilerplate, and every caller uses identical
code. Make this easier by instead introducing a new boolean value where
the default value (0) does what we want so that new callers of
unpack_trees() automatically get the appropriate behavior. And move all
the handling of unpack_trees_options.dir into unpack_trees() itself.
While preserve_ignored = 0 is the behavior we feel is the appropriate
default, we defer fixing commands to use the appropriate default until a
later commit. So, this commit introduces several locations where we
manually set preserve_ignored=1. This makes it clear where code paths
were previously preserving ignored files when they should not have been;
a future commit will flip these to instead use a value of 0 to get the
behavior we want.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Various mergy operations have been prepared to work efficiently
with the sparse index.
* ds/mergies-with-sparse-index:
sparse-index: integrate with cherry-pick and rebase
sequencer: ensure full index if not ORT strategy
t1092: add cherry-pick, rebase tests
merge-ort: expand only for out-of-cone conflicts
merge: make sparse-aware with ORT
diff: ignore sparse paths in diffstat
Not sure what happened, but the comment is describing code elsewhere in
the file. Fix the comment to actually discuss the code that follows.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merge conflicts happen often enough to want to avoid expanding a sparse
index when they happen, as long as those conflicts are within the
sparse-checkout cone. If a conflict exists outside of the
sparse-checkout cone, then we still need to expand before iterating over
the index entries. This is critical to do in advance because of how the
original_cache_nr is tracked to allow inserting and replacing cache
entries.
Iterate over the conflicted files and check if any paths are outside of
the sparse-checkout cone. If so, then expand the full index.
Add a test that demonstrates that we do not expand the index, even when
we hit a conflict within the sparse-checkout cone.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
