"git am --abort" sometimes complained about not being able to write
a tree with an 0{40} object in it.
* jk/two-way-merge-corner-case-fix:
t1005: add test for "read-tree --reset -u A B"
t1005: reindent
unpack-trees: fix "read-tree -u --reset A B" with conflicted index
Some buffers created with PATH_MAX length are not checked when being
written, and can overflow if PATH_MAX is not big enough to hold the
path.
Replace those buffers by strbufs so that their size is automatically
grown if necessary. They are created as static local variables to avoid
reallocating memory on each call. Note that prefix_filename() returns
this static buffer so each callers should copy or use the string
immediately (this is currently true).
Reported-by: Wataru Noguchi <wnoguchi.0727@gmail.com>
Signed-off-by: Antoine Pelisse <apelisse@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Fix a rather longstanding corner-case bug in twoway "reset to
there" merge, which is most often seen in "git am --abort".
* jk/two-way-merge-corner-case-fix:
t1005: add test for "read-tree --reset -u A B"
t1005: reindent
unpack-trees: fix "read-tree -u --reset A B" with conflicted index
The new hashmap implementation supports remove, so really remove unused
cache entries from the name hashmap instead of just marking them.
The CE_UNHASHED flag and CE_STATE_MASK are no longer needed.
Keep the CE_HASHED flag to prevent adding entries twice.
Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Note: the "ce->next = NULL;" in unpack-trees.c::do_add_entry can safely be
removed, as ce->next (now ce->ent.next) is always properly initialized in
name-hash.c::hash_index_entry.
Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we call "read-tree --reset -u HEAD ORIG_HEAD", the first thing we
do with the index is to call read_cache_unmerged. Originally that
would read the index, leaving aside any unmerged entries. However, as
of d1a43f2 (reset --hard/read-tree --reset -u: remove unmerged new
paths, 2008-10-15), it actually creates a new cache entry to serve as
a placeholder, so that we later know to update the working tree.
However, we later noticed that the sha1 of that unmerged entry was
just copied from some higher stage, leaving you with random content in
the index. That was fixed by e11d7b5 ("reset --merge": fix unmerged
case, 2009-12-31), which instead puts the null sha1 into the newly
created entry, and sets a CE_CONFLICTED flag. At the same time, it
teaches the unpack-trees machinery to pay attention to this flag, so
that oneway_merge throws away the current value.
However, it did not update the code paths for twoway_merge, which is
where we end up in the two-way read-tree with --reset. We notice that
the HEAD and ORIG_HEAD versions are the same, and say "oh, we can just
reuse the current version". But that's not true. The current version
is bogus.
Notice this case and make sure we do not keep the bogus entry; either
we do not have that path in the tree we are moving to (i.e. remove
it), or we want to have the cache entry we created for the tree we are
moving to (i.e. resolve by explicitly saying the "newtree" version is
what we want).
[jc: this is from the almost year-old $gmane/212316]
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Each caller of index_name_exists() knows whether it is looking for a
directory or a file, and can avoid the unnecessary indirection of
index_name_exists() by instead calling index_dir_exists() or
index_file_exists() directly.
Invoking the appropriate search function explicitly will allow a
subsequent patch to relieve callers of the artificial burden of having
to add a trailing '/' to the pathname given to index_dir_exists().
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Before overwriting the destination index, first let's discard its
contents.
Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Tested-by: Лежанкин Иван <abyss.7@gmail.com> wrote:
Reviewed-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
I attempted to make index_state->cache[] a "const struct cache_entry **"
to find out how existing entries in index are modified and where. The
question I have is what do we do if we really need to keep track of on-disk
changes in the index. The result is
- diff-lib.c: setting CE_UPTODATE
- name-hash.c: setting CE_HASHED
- preload-index.c, read-cache.c, unpack-trees.c and
builtin/update-index: obvious
- entry.c: write_entry() may refresh the checked out entry via
fill_stat_cache_info(). This causes "non-const struct cache_entry
*" in builtin/apply.c, builtin/checkout-index.c and
builtin/checkout.c
- builtin/ls-files.c: --with-tree changes stagemask and may set
CE_UPDATE
Of these, write_entry() and its call sites are probably most
interesting because it modifies on-disk info. But this is stat info
and can be retrieved via refresh, at least for porcelain
commands. Other just uses ce_flags for local purposes.
So, keeping track of "dirty" entries is just a matter of setting a
flag in index modification functions exposed by read-cache.c. Except
unpack-trees, the rest of the code base does not do anything funny
behind read-cache's back.
The actual patch is less valueable than the summary above. But if
anyone wants to re-identify the above sites. Applying this patch, then
this:
diff --git a/cache.h b/cache.h
index 430d021..1692891 100644
--- a/cache.h
+++ b/cache.h
@@ -267,7 +267,7 @@ static inline unsigned int canon_mode(unsigned int mode)
#define cache_entry_size(len) (offsetof(struct cache_entry,name) + (len) + 1)
struct index_state {
- struct cache_entry **cache;
+ const struct cache_entry **cache;
unsigned int version;
unsigned int cache_nr, cache_alloc, cache_changed;
struct string_list *resolve_undo;
will help quickly identify them without bogus warnings.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If o->merge is set, the struct traverse_info member conflicts is shifted
left in unpack_callback, then passed through traverse_trees_recursive
to unpack_nondirectories, where it is shifted right before use. Stop
the shifting and just pass the conflict bit mask as is. Rename the
member to df_conflicts to prove that it isn't used anywhere else.
Signed-off-by: René Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The merge functions duplicate entries as needed and they don't free
them. Release them in unpack_nondirectories, the same function
where they were allocated, after we're done.
As suggested by Felipe, use the same loop style (zero-based for loop)
for freeing as for allocating.
Improved-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: René Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change the type merge_fn_t to accept the array of cache_entry pointers
as const pointers to const pointers. This documents the fact that the
merge functions don't modify the cache_entry contents or replace any of
the pointers in the array.
Only a single cast is necessary in unpack_nondirectories because adding
two const modifiers at once is not allowed in C. The cast is safe in
that it doesn't mask any modfication; call_unpack_fn only needs the
array for reading.
Signed-off-by: René Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add const to struct cache_entry pointers throughout the tree which are
only used for reading. This allows callers to pass in const pointers.
Signed-off-by: René Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Duplicate the merge entry right away and work with that instead of
modifying the entry we got and duplicating it only at the end of
the function. Then mark that pointer const to document that we
don't modify the referenced cache_entry.
This change is safe because all existing merge functions call
merged_entry just before returning (or not at all), i.e. they don't
care about changes to the referenced cache_entry after the call.
unpack_nondirectories and unpack_index_entry, which call the merge
functions through call_unpack_fn, aren't interested in such changes
neither.
The change complicates merged_entry a bit because we have to free the
copy if we error out, but allows callers to pass a const pointer.
Signed-off-by: René Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
While we're add it, mark the struct cache_entry pointer of add_entry
const because we only read from it and this allows callers to pass in
const pointers.
Signed-off-by: René Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a new command "git check-ignore" for debugging .gitignore
files.
The variable names may want to get cleaned up but that can be done
in-tree.
* as/check-ignore:
clean.c, ls-files.c: respect encapsulation of exclude_list_groups
t0008: avoid brace expansion
add git-check-ignore sub-command
setup.c: document get_pathspec()
add.c: extract new die_if_path_beyond_symlink() for reuse
add.c: extract check_path_for_gitlink() from treat_gitlinks() for reuse
pathspec.c: rename newly public functions for clarity
add.c: move pathspec matchers into new pathspec.c for reuse
add.c: remove unused argument from validate_pathspec()
dir.c: improve docs for match_pathspec() and match_pathspec_depth()
dir.c: provide clear_directory() for reclaiming dir_struct memory
dir.c: keep track of where patterns came from
dir.c: use a single struct exclude_list per source of excludes
Conflicts:
builtin/ls-files.c
dir.c
Refactor and generally clean up the directory traversal API
implementation.
* as/dir-c-cleanup:
dir.c: rename free_excludes() to clear_exclude_list()
dir.c: refactor is_path_excluded()
dir.c: refactor is_excluded()
dir.c: refactor is_excluded_from_list()
dir.c: rename excluded() to is_excluded()
dir.c: rename excluded_from_list() to is_excluded_from_list()
dir.c: rename path_excluded() to is_path_excluded()
dir.c: rename cryptic 'which' variable to more consistent name
Improve documentation and comments regarding directory traversal API
api-directory-listing.txt: update to match code
Previously each exclude_list could potentially contain patterns
from multiple sources. For example dir->exclude_list[EXC_FILE]
would typically contain patterns from .git/info/exclude and
core.excludesfile, and dir->exclude_list[EXC_DIRS] could contain
patterns from multiple per-directory .gitignore files during
directory traversal (i.e. when dir->exclude_stack was more than
one item deep).
We split these composite exclude_lists up into three groups of
exclude_lists (EXC_CMDL / EXC_DIRS / EXC_FILE as before), so that each
exclude_list now contains patterns from a single source. This will
allow us to cleanly track the origin of each pattern simply by adding
a src field to struct exclude_list, rather than to struct exclude,
which would make memory management of the source string tricky in the
EXC_DIRS case where its contents are dynamically generated.
Similarly, by moving the filebuf member from struct exclude_stack to
struct exclude_list, it allows us to track and subsequently free
memory buffers allocated during the parsing of all exclude files,
rather than only tracking buffers allocated for files in the EXC_DIRS
group.
Signed-off-by: Adam Spiers <git@adamspiers.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It is clearer to use a 'clear_' prefix for functions which empty
and deallocate the contents of a data structure without freeing
the structure itself, and a 'free_' prefix for functions which
also free the structure itself.
http://article.gmane.org/gmane.comp.version-control.git/206128
Signed-off-by: Adam Spiers <git@adamspiers.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Continue adopting clearer names for exclude functions. This 'is_*'
naming pattern for functions returning booleans was discussed here:
http://thread.gmane.org/gmane.comp.version-control.git/204661/focus=204924
Also adjust their callers as necessary.
Signed-off-by: Adam Spiers <git@adamspiers.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Start adopting clearer names for exclude functions. This 'is_*'
naming pattern for functions returning booleans was agreed here:
http://thread.gmane.org/gmane.comp.version-control.git/204661/focus=204924
Signed-off-by: Adam Spiers <git@adamspiers.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Although the subject line of 613f027 (read-tree -u one-way merge fix
to check out locally modified paths., 2006-05-15) mentions "read-tree
-u", it did not seem to check whether -u was in effect. Not checking
whether -u is in effect makes e.g. "read-tree --reset" lstat() the
worktree, even though the worktree stat should not matter for that
operation.
This speeds up e.g. "git reset" a little on the linux-2.6 repo (best
of five, warm cache):
Before After
real 0m0.288s 0m0.233s
user 0m0.190s 0m0.150s
sys 0m0.090s 0m0.080s
Signed-off-by: Martin von Zweigbergk <martinvonz@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Split lower bits of ce_flags field and creates a new ce_namelen
field in the in-core index structure.
* tg/ce-namelen-field:
Strip namelen out of ce_flags into a ce_namelen field
"git ls-files --exclude=t -i" did not consider anything under t/ as
excluded, as it did not pay attention to exclusion of leading paths
while walking the index. Other two users of excluded() are also
updated.
* jc/ls-files-i-dir:
dir.c: make excluded() file scope static
unpack-trees.c: use path_excluded() in check_ok_to_remove()
builtin/add.c: use path_excluded()
path_excluded(): update API to less cache-entry centric
ls-files -i: micro-optimize path_excluded()
ls-files -i: pay attention to exclusion of leading paths
Strip the name length from the ce_flags field and move it
into its own ce_namelen field in struct cache_entry. This
will both give us a tiny bit of a performance enhancement
when working with long pathnames and is a refactoring for
more readability of the code.
It enhances readability, by making it more clear what
is a flag, and where the length is stored and make it clear
which functions use stages in comparisions and which only
use the length.
It also makes CE_NAMEMASK private, so that users don't
mistakenly write the name length in the flags.
Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Replace strlen(ce->name) with ce_namelen() in a couple
of places which gives us some additional bits of
performance.
Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git ls-files --exclude=t -i" did not consider anything under t/
as excluded, as it did not pay attention to exclusion of leading
paths while walking the index. Other two users of excluded() are
also updated.
* jc/ls-files-i-dir:
dir.c: make excluded() file scope static
unpack-trees.c: use path_excluded() in check_ok_to_remove()
builtin/add.c: use path_excluded()
path_excluded(): update API to less cache-entry centric
ls-files -i: micro-optimize path_excluded()
ls-files -i: pay attention to exclusion of leading paths
This function is responsible for determining if a path that is not
tracked is ignored and allow "checkout" to overwrite it as needed.
It used excluded() without checking if higher level directory in the
path is ignored; correct it to use path_excluded() for this check.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
* There are uses of lower-level interface excluded_from_list() in
the codepath for narrow-checkout hack; they are supposed to be
already checking each level as they descend, and are not touched
with this patch.
By Jens Lehmann (1) and Johannes Sixt (1)
* maint:
Consistently use "superproject" instead of "supermodule"
t3404: begin "exchange commits with -p" test with correct preconditions
We fairly consistently say "superproject" and never "supermodule" these
days. But there are seven occurrences of "supermodule" left in the current
work tree. Three appear in Release Notes for 1.5.3 and 1.7.7, three in
test names and one in a C-code comment.
Replace all occurrences of "supermodule" outside of the Release Notes
(which shouldn't be changed after the fact) with "superproject" for
consistency.
Signed-off-by: Jens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Many error/warning messages had extra trailing newlines that are
unnecessary.
By Pete Wyckoff
* pw/message-cleanup:
remove blank filename in error message
remove superfluous newlines in error messages
Trivially shrinks the on-disk size of the index file to save both I/O and
checksum overhead.
The topic should give a solid base to build on further updates, with the
code refactoring in its earlier parts, and the backward compatibility
mechanism in its later parts.
* jc/index-v4:
index-v4: document the entry format
unpack-trees: preserve the index file version of original
update-index: upgrade/downgrade on-disk index version
read-cache.c: write prefix-compressed names in the index
read-cache.c: read prefix-compressed names in index on-disk version v4
read-cache.c: move code to copy incore to ondisk cache to a helper function
read-cache.c: move code to copy ondisk to incore cache to a helper function
read-cache.c: report the header version we do not understand
read-cache.c: make create_from_disk() report number of bytes it consumed
read-cache.c: allow unaligned mapping of the index file
cache.h: hide on-disk index details
varint: make it available outside the context of pack
The error handling routines add a newline. Remove
the duplicate ones in error messages.
Signed-off-by: Pete Wyckoff <pw@padd.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Otherwise "git checkout $other_branch" (or even "git checkout HEAD")
would end up writing the index out in the default format.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The allocations made by unpack_nondirectories() using create_ce_entry()
are never freed.
In the non-merge case, we duplicate them using add_entry() and later
only look at the first allocated element (src[0]), perhaps even only
by mistake. Split out the actual addition from add_entry() into the
new helper do_add_entry() and call this non-duplicating function
instead of add_entry() to avoid the leak.
Valgrind reports this for the command "git archive v1.7.9" without
the patch:
==13372== LEAK SUMMARY:
==13372== definitely lost: 230,986 bytes in 2,325 blocks
==13372== indirectly lost: 0 bytes in 0 blocks
==13372== possibly lost: 98 bytes in 1 blocks
==13372== still reachable: 2,259,198 bytes in 3,243 blocks
==13372== suppressed: 0 bytes in 0 blocks
And with the patch applied:
==13375== LEAK SUMMARY:
==13375== definitely lost: 65 bytes in 1 blocks
==13375== indirectly lost: 0 bytes in 0 blocks
==13375== possibly lost: 0 bytes in 0 blocks
==13375== still reachable: 2,364,417 bytes in 3,245 blocks
==13375== suppressed: 0 bytes in 0 blocks
Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
src[0] points to the index entry in the merge case and to the first
tree to unpack in the non-merge case. We only want to mark the index
entry, so check first if we're merging.
Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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>
* nd/maint-sparse-errors:
Add explanation why we do not allow to sparse checkout to empty working tree
sparse checkout: show error messages when worktree shaping fails
* mg/maint-doc-sparse-checkout:
git-read-tree.txt: correct sparse-checkout and skip-worktree description
git-read-tree.txt: language and typography fixes
unpack-trees: print "Aborting" to stderr
* jc/diff-index-unpack:
diff-index: pass pathspec down to unpack-trees machinery
unpack-trees: allow pruning with pathspec
traverse_trees(): allow pruning with pathspec
verify_* functions can queue errors up and to be printed later at
label return_failed. In case of errors, do not go to label "done"
directly because all queued messages would be dropped on the floor.
Found-by: Joshua Jensen <jjensen@workspacewhiz.com>
Tracked-down-by: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
display_error_msgs() prints all the errors to stderr already (if any),
followed by "Aborting" (if any) to stdout. Make the latter go to stderr
instead.
Signed-off-by: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Use the pathspec pruning of traverse_trees() from unpack_trees(). Again,
the unpack_trees() machinery is primarily meant for merging two (or more)
trees, and because a merge is a full tree operation, it didn't support any
pruning with pathspec, and this codepath probably should not be enabled
while running a merge, but the caller in diff-lib.c::diff_cache() should
be able to take advantage of it.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* maint:
Break down no-lstat() condition checks in verify_uptodate()
t7400: fix bogus test failure with symlinked trash
Documentation: clarify the invalidated tree entry format
Make it easier to grok under what conditions we can skip lstat().
While at there, shorten ie_match_stat() line for the sake of my eyes.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A negative return from the unpack callback function usually means unpack
failed for the entry and signals the unpack_trees() machinery to fail the
entire merge operation, immediately and there is no other way for the
callback to tell the machinery to exit early without reporting an error.
This is what we usually want to make a merge all-or-nothing operation, but
the machinery is also used for diff-index codepath by using a custom
unpack callback function. And we do sometimes want to exit early without
failing, namely when we are under --quiet and can short-cut the diff upon
finding the first difference.
Add "exiting_early" field to unpack_trees_options structure, to signal the
unpack_trees() machinery that the negative return value is not signaling
an error but an early return from the unpack_trees() machinery. As this by
definition hasn't unpacked everything, discard the resulting index just
like the failure codepath.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Until now there was no way to test if unpack_trees() with update=1 would
succeed without really updating the work tree. The reason for that is that
setting update to 0 does skip the tests for new files and deactivates the
sparse handling, thereby making that unsuitable as a dry run.
Add the new dry_run flag to struct unpack_trees_options unpack_trees().
Setting that together with the update flag will check if the work tree
update would be successful without doing it for real.
The only class of problems that is not detected at the moment are file
system conditions like ENOSPC or missing permissions. Also the index
entries of updated files are not as they would be after a real checkout
because lstat() isn't run as the files aren't updated for real.
Signed-off-by: Jens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Sparse-setting code follows closely how files are excluded in
read_directory(), every entry (including directories) are fed to
excluded_from_list() to decide if the entry is suitable. Directories
are treated no different than files. If a directory is matched (or
not), the whole directory is considered matched (or not) and the
process moves on.
This generally works as long as there are no patterns to exclude parts
of the directory. In case of sparse checkout code, the following patterns
t
!t/t0000-basic.sh
will produce a worktree with full directory "t" even if t0000-basic.sh
is requested to stay out.
By the same reasoning, if a directory is to be excluded, any rules to
re-include certain files within that directory will be ignored.
Fix it by always checking files against patterns. If no pattern can be
used to decide whether an entry is in our out
(ie. excluded_from_list() returns -1), the entry will be
included/excluded the same as their parent directory.
Noticed-by: <skillzero@gmail.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Fix warnings from 'make check'.
- These files don't include 'builtin.h' causing sparse to complain that
cmd_* isn't declared:
builtin/clone.c:364, builtin/fetch-pack.c:797,
builtin/fmt-merge-msg.c:34, builtin/hash-object.c:78,
builtin/merge-index.c:69, builtin/merge-recursive.c:22
builtin/merge-tree.c:341, builtin/mktag.c:156, builtin/notes.c:426
builtin/notes.c:822, builtin/pack-redundant.c:596,
builtin/pack-refs.c:10, builtin/patch-id.c:60, builtin/patch-id.c:149,
builtin/remote.c:1512, builtin/remote-ext.c:240,
builtin/remote-fd.c:53, builtin/reset.c:236, builtin/send-pack.c:384,
builtin/unpack-file.c:25, builtin/var.c:75
- These files have symbols which should be marked static since they're
only file scope:
submodule.c:12, diff.c:631, replace_object.c:92, submodule.c:13,
submodule.c:14, trace.c:78, transport.c:195, transport-helper.c:79,
unpack-trees.c:19, url.c:3, url.c:18, url.c:104, url.c:117, url.c:123,
url.c:129, url.c:136, thread-utils.c:21, thread-utils.c:48
- These files redeclare symbols to be different types:
builtin/index-pack.c:210, parse-options.c:564, parse-options.c:571,
usage.c:49, usage.c:58, usage.c:63, usage.c:72
- These files use a literal integer 0 when they really should use a NULL
pointer:
daemon.c:663, fast-import.c:2942, imap-send.c:1072, notes-merge.c:362
While we're in the area, clean up some unused #includes in builtin files
(mostly exec_cmd.h).
Signed-off-by: Stephen Boyd <bebarino@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When check_leading_path notices a file in the way of a new entry to be
checked out, verify_absent uses (1) the mode to determine whether it
is a directory (2) the rest of the stat information to check if this
is actually an old entry, disguised by a change in filename (e.g.,
README -> Readme) that is significant to git but insignificant to the
underlying filesystem. If lstat fails, these checks are performed
with an uninitialied stat structure, producing essentially random
results.
Better to just error out when lstat fails.
The easiest way to reproduce this is to remove a file after the
check_leading_path call and before the lstat in verify_absent. An
lstat failure other than ENOENT in check_leading_path would also
trigger the same code path.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When check_leading_path notices no file in the way of the new entry to
be checked out, verify_absent checks whether there is a directory
there or nothing at all. If that lstat call fails (for example due to
ENOMEM), it assumes ENOENT, meaning a directory with untracked files
would be clobbered in that case.
Check errno after calling lstat, and for conditions other than ENOENT,
just error out.
This is a theoretical race condition. lstat has to succeed moments
before it fails for there to be trouble.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
unpack_trees() merges two trees (the current HEAD and the destination
commit) when switching to another branch, checking and updating the index
entry where the destination differs from the current HEAD. It merges three
trees (the common ancestor, the current HEAD and the other commit) when
performing a three-way merge, checking and updating the index entry when
the merge result differs from the current HEAD. It does so by walking the
input trees in parallel all the way down to the leaves.
One common special case is a directory is identical across the trees
involved in the merge. In such a case, we do not have to descend into the
directory at all---we know that the end result is to keep the entries in
the current index.
This optimization cannot be applied in a few special cases in
unpack_trees(), though. We need to descend into the directory and update
the index entries from the target tree in the following cases:
- When resetting (e.g. "git reset --hard"); and
- When checking out a tree for the first time into an empty working tree
(e.g. "git read-tree -m -u HEAD HEAD" with missing .git/index).
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* nd/maint-fix-add-typo-detection:
Revert "excluded_1(): support exclude files in index"
unpack-trees: fix sparse checkout's "unable to match directories"
unpack-trees: move all skip-worktree checks back to unpack_trees()
dir.c: add free_excludes()
cache.h: realign and use (1 << x) form for CE_* constants
An aborted merge prints the list of rejected paths as part of the
error message. Since commit f66caaf9 (do not overwrite files in
leading path), some of those paths do not have static buffers, so
we have to keep a copy. Use string_list's to accomplish this.
This changes the order of the list to the order in which the paths
are processed. Previously, it was reversed.
Signed-off-by: Clemens Buchacher <drizzd@aon.at>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If the work tree contains an untracked file x, and
unpack-trees wants to checkout a path x/*, the
file x is removed unconditionally.
Instead, apply the same checks that are normally
used for untracked files, and abort if the file
cannot be removed.
Signed-off-by: Clemens Buchacher <drizzd@aon.at>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This wraps some inline code into the function check_ok_to_remove(),
which will later be used for leading path components as well.
Signed-off-by: Clemens Buchacher <drizzd@aon.at>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Matching index entries against an excludes file currently has two
problems.
First, there's no function to do it. Code paths (like sparse
checkout) that wanted to try it would iterate over index entries and
for each index entry pass that path to excluded_from_list(). But that
is not how excluded_from_list() works; one is supposed to feed in each
ancester of a path before a given path to find out if it was excluded
because of some parent or grandparent matching a
bigsubdirectory/
pattern despite the path not matching any .gitignore pattern directly.
Second, it's inefficient. The excludes mechanism is supposed to let
us block off vast swaths of the filesystem as uninteresting; separately
checking every index entry doesn't fit that model.
Introduce a new function to take care of both these problems. This
traverses the index in depth-first order (well, that's what order the
index is in) to mark un-excluded entries.
Maybe some day the in-core index format will be restructured to make
this sort of operation easier. Or maybe we will want to try some
binary search based thing. The interface is simple enough to allow
all those things. Example:
clear_ce_flags(the_index.cache, the_index.cache_nr,
CE_CANDIDATE, CE_CLEARME, exclude_list);
would clear the CE_CLEARME flag on all index entries with
CE_CANDIDATE flag and not matched by exclude_list.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Earlier, the will_have_skip_worktree() checks are done in various
places, which makes it hard to traverse the index tree-alike, required
by excluded_from_list(). This patch moves all the checks into two
loops in unpack_trees().
Entries in index in this operation can be classified into two
groups: ones already in index before unpack_trees() is called and ones
added to index after traverse_trees() is called.
In both groups, before checking file status on worktree, the future
skip-worktree bit must be checked, so that if an entry will be outside
worktree, worktree should not be checked.
For the first group, the future skip-worktree bit is precomputed and
stored as CE_NEW_SKIP_WORKTREE in the first loop before
traverse_trees() is called so that *way_merge() function does not need
to compute it again.
For the second group, because we don't know what entries will be in
this group until traverse_trees() finishes, operations that need
future skip-worktree check is delayed until CE_NEW_SKIP_WORKTREE is
computed in the second loop. CE_ADDED is used to mark entries in the
second group.
CE_ADDED and CE_NEW_SKIP_WORKTREE are temporary flags used in
unpack_trees(). CE_ADDED is only used by add_to_index(), which should
not be called while unpack_trees() is running.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
An aborted merge prints the list of rejected paths as part of the
error message. Since commit f66caaf9 (do not overwrite files in
leading path), some of those paths do not have static buffers, so
we have to keep a copy. Use string_list's to accomplish this.
This changes the order of the list to the order in which the paths
are processed. Previously, it was reversed.
Signed-off-by: Clemens Buchacher <drizzd@aon.at>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If the work tree contains an untracked file x, and
unpack-trees wants to checkout a path x/*, the
file x is removed unconditionally.
Instead, apply the same checks that are normally
used for untracked files, and abort if the file
cannot be removed.
Signed-off-by: Clemens Buchacher <drizzd@aon.at>
This wraps some inline code into the function check_ok_to_remove(),
which will later be used for leading path components as well.
Signed-off-by: Clemens Buchacher <drizzd@aon.at>
* dg/local-mod-error-messages:
t7609-merge-co-error-msgs: test non-fast forward case too.
Move "show_all_errors = 1" to setup_unpack_trees_porcelain()
setup_unpack_trees_porcelain: take the whole options struct as parameter
Move set_porcelain_error_msgs to unpack-trees.c and rename it
Conflicts:
merge-recursive.c
Not only this makes the code clearer since setting up the porcelain error
message is meant to work with show_all_errors, but this fixes a call to
setup_unpack_trees_porcelain() in git_merge_trees() which did not set
show_all_errors.
add_rejected_path() used to double-check whether it was running in
plumbing mode. This check was ineffective since it was setting
show_all_errors too late for traverse_trees() to see it, and is made
useless by this patch. Remove it.
Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This is a preparation patch to let setup_unpack_trees_porcelain set
show_all_errors itself.
Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The function is currently dealing only with error messages, but the
intent of calling it is really to notify the unpack-tree mechanics that
it is running in porcelain mode.
Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* nd/fix-sparse-checkout:
unpack-trees: mark new entries skip-worktree appropriately
unpack-trees: do not check for conflict entries too early
unpack-trees: let read-tree -u remove index entries outside sparse area
unpack-trees: only clear CE_UPDATE|CE_REMOVE when skip-worktree is always set
t1011 (sparse checkout): style nitpicks
* dg/local-mod-error-messages:
t7609: test merge and checkout error messages
unpack_trees: group error messages by type
merge-recursive: distinguish "removed" and "overwritten" messages
merge-recursive: porcelain messages for checkout
Turn unpack_trees_options.msgs into an array + enum
Conflicts:
t/t3400-rebase.sh
When an error is encountered, it calls add_rejected_file() which either
- directly displays the error message and stops if in plumbing mode
(i.e. if show_all_errors is not initialized at 1)
- or stores it so that it will be displayed at the end with display_error_msgs(),
Storing the files by error type permits to have a list of files for
which there is the same error instead of having a serie of almost
identical errors.
As each bind_overlap error combines a file and an old file, a list cannot be
done, therefore, theses errors are not stored but directly displayed.
Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
To limit the number of possible error messages, the error messages for
the case would_lose_untracked_file and would_lose_orphaned in
unpack_trees_options.msgs were handled with a single string,
parameterized by an action string ("overwritten" or "removed").
Instead, we consider them as two different cases, with unparameterized
string. This will make it easier to make separate lists sorted by error
types later.
Only the bind_overlap case still takes two %s parameters, but that's
unavoidable.
Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A porcelain message was first added in checkout.c in the commit
8ccba008 (Junio C Hamano, Sat May 17 21:03:49 2008, unpack-trees:
allow Porcelain to give different error messages) to give better feedback
in the case of merge errors.
This patch adapts the porcelain messages for the case of checkout
instead. This way, when having a checkout error, "merge" no longer
appears in the error message.
While we're there, we add an advice in the case of
would_lose_untracked_file.
Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The list of error messages was introduced as a structure, but an array
indexed over an enum is more flexible, since it allows one to store a
type of error message (index in the array) in a variable.
This change needs to rename would_lose_untracked ->
would_lose_untracked_file to avoid a clash with the function
would_lose_untracked in merge-recursive.c.
Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The underlying problem is that the fill_tree_descriptor()
API is easy to misuse, and this patch does not fix that.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Sparse checkout narrows worktree down based on the skip-worktree bit
before and after $GIT_DIR/info/sparse-checkout application. If it does
not have that bit before but does after, a narrow is detected and the
file will be removed from worktree.
New files added by merge, however, does not have skip-worktree bit. If
those files appear to be outside checkout area, the same rule applies:
the file gets removed from worktree even though they don't exist in
worktree.
Just pretend they have skip-worktree before in that case, so the rule
is ignored.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The idea of sparse checkout is conflict entries should always stay
in worktree, regardless $GIT_DIR/info/sparse-checkout. Therefore,
ce_stage(ce) usually means no CE_SKIP_WORKTREE. This is true when all
entries have been merged into the index, and identical staged entries
collapsed.
However, will_have_skip_worktree() since f1f523e (unpack-trees():
ignore worktree check outside checkout area) is also used earlier in
verify_* functions, where entries have not been merged to index yet
and ce_stage() is not zero. Checking ce_stage() then may provoke
unnecessary verification on entries outside checkout area and error
out.
This fixes part of test case "read-tree adds to worktree, dirty case".
The error
error: Untracked working tree file 'sub/added' would be overwritten by merge.
is now gone and (unfortunately) replaced by another error, which will
be addressed in the next patch.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
To avoid touching the worktree outside a sparse checkout,
when the update flag is enabled unpack_trees() clears the
CE_UPDATE and CE_REMOVE flags on entries that do not match the
sparse pattern before actually committing any updates to the
index file or worktree.
The effect on the index was unintentional; sparse checkout was
never meant to prevent index updates outside the area checked
out. And the result is very confusing: for example, after a
failed merge, currently "git reset --hard" does not reset the
state completely but an additional "git reset --mixed" will.
So stop clearing the CE_REMOVE flag. Instead, maintain a
CE_WT_REMOVE flag to separately track whether a particular
file removal should apply to the worktree in addition to the
index or not.
The CE_WT_REMOVE flag is used already to mark files that
should be removed because of a narrowing checkout area. That
usage will still apply; do not clear the CE_WT_REMOVE flag
in that case (detectable because the CE_REMOVE flag is not
set).
This bug masked some other bugs illustrated by the test
suite, which will be addressed by later patches.
Reported-by: Frédéric Brière <fbriere@fbriere.net>
Fixes: http://bugs.debian.org/583699
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The purpose of this clearing is, as explained in comment, because
verify_*() may set those bits before apply_sparse_checkout() is
called. By that time, it's not clear whether an entry will stay in
checkout area or out. After $GIT_DIR/info/sparse-checkout is applied,
we know what entries will be in finally. It's time to clean unwanted
bits.
That works perfectly when checkout area remains unchanged. When
checkout area changes, apply_sparse_checkout() may set CE_UPDATE
or CE_WT_REMOVE to widen/narrow checkout area. Doing the clearing
after apply_sparse_checkout() may clear those widening/narrowing
bits unexpectedly.
So, only do that on entries that are not affected by checkout area
changes (i.e. skip-worktree bit does not change after
apply_sparse_checkout).
This code does not actually fix anything though, just
future-proof. The removed code and the narrow/widen code inside
apply_sparse_checkout are currently independent (narrow code never
sets CE_REMOVE, widen code sets CE_UPDATE, but ce_skip_worktree()
would be false).
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* gv/portable:
test-lib: use DIFF definition from GIT-BUILD-OPTIONS
build: propagate $DIFF to scripts
Makefile: Tru64 portability fix
Makefile: HP-UX 10.20 portability fixes
Makefile: HPUX11 portability fixes
Makefile: SunOS 5.6 portability fix
inline declaration does not work on AIX
Allow disabling "inline"
Some platforms lack socklen_t type
Make NO_{INET_NTOP,INET_PTON} configured independently
Makefile: some platforms do not have hstrerror anywhere
git-compat-util.h: some platforms with mmap() lack MAP_FAILED definition
test_cmp: do not use "diff -u" on platforms that lack one
fixup: do not unconditionally disable "diff -u"
tests: use "test_cmp", not "diff", when verifying the result
Do not use "diff" found on PATH while building and installing
enums: omit trailing comma for portability
Makefile: -lpthread may still be necessary when libc has only pthread stubs
Rewrite dynamic structure initializations to runtime assignment
Makefile: pass CPPFLAGS through to fllow customization
Conflicts:
Makefile
wt-status.h
When traversing trees with an index, the current index pointer
(o->cache_bottom) occasionally has to be temporarily advanced forwards to
match the traversal order of the tree, which is not the same as the sort
order of the index. The existing algorithm that did this (introduced in
730f72840c) would get "stuck" when the
cache_bottom was popped and then repeatedly check the same index entries
over and over. This represents a serious performance regression for
large repositories compared to the old "broken" traversal order.
This commit makes a simple change to mitigate this. Whenever
find_cache_pos sees that the current pos is also the cache_bottom, and
it has already been unpacked, it advances the cache_bottom as well as
the current pos. This prevents the above "sticking" behavior without
dramatically changing the algorithm.
In addition, this commit moves the unpacked check above the
ce_in_traverse_path() check. The simple bitmask check is cheaper, and
in the case described above will be firing quite a bit to advance the
cache_bottom after a tree pop.
This yields considerable performance improvements for large trees.
The following are the number of function calls for "git diff HEAD" on
the Linux kernel tree, with 33,307 files:
Symbol Calls Before Calls After
------------------- ------------ -----------
unpack_callback 35,332 35,332
find_cache_pos 37,357 37,357
ce_in_traverse_path 4,979,473 37,357
do_compare_entry 6,828,181 251,925
df_name_compare 6,828,181 251,925
And on a repository of 187,456 files:
Symbol Calls Before Calls After
------------------- ------------ -----------
unpack_callback 197,958 197,958
find_cache_pos 208,460 208,460
ce_in_traverse_path 37,308,336 208,460
do_compare_entry 156,950,469 2,690,626
df_name_compare 156,950,469 2,690,626
On the latter repository, user time for "git diff HEAD" was reduced from
5.58 to 0.42 seconds. This is compared to 0.30 seconds before the
traversal order fix was implemented.
Signed-off-by: Brian Downing <bdowning@lavos.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Unfortunately, there are still plenty of production systems with
vendor compilers that choke unless all compound declarations can be
determined statically at compile time, for example hpux10.20 (I can
provide a comprehensive list of our supported platforms that exhibit
this problem if necessary).
This patch simply breaks apart any compound declarations with dynamic
initialisation expressions, and moves the initialisation until after
the last declaration in the same block, in all the places necessary to
have the offending compilers accept the code.
Signed-off-by: Gary V. Vaughan <gary@thewrittenword.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A merge will fail gracefully if it needs to update files marked
"assume unchanged", but other similar commands will not. In
particular, checkout and rebase will silently overwrite changes to
such files.
This is a regression introduced in commit 1dcafcc0 (verify_uptodate():
add ce_uptodate(ce) test), which avoids lstat's during a merge, if the
index entry is up-to-date. If the CE_VALID flag is set, however, we
cannot trust CE_UPTODATE.
Signed-off-by: Clemens Buchacher <drizzd@aon.at>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This patch introduces the remove_or_warn function which is a
generalised version of the {unlink,rmdir}_or_warn functions. It takes
an additional parameter indicating the mode of the file to be removed.
The patch also modifies certain functions to use remove_or_warn
where appropriate, and adds a test case for a bug fixed by the use
of remove_or_warn.
Signed-off-by: Peter Collingbourne <peter@pcc.me.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* jc/fix-tree-walk:
read-tree --debug-unpack
unpack-trees.c: look ahead in the index
unpack-trees.c: prepare for looking ahead in the index
Aggressive three-way merge: fix D/F case
traverse_trees(): handle D/F conflict case sanely
more D/F conflict tests
tests: move convenience regexp to match object names to test-lib.sh
Conflicts:
builtin-read-tree.c
unpack-trees.c
unpack-trees.h
* cc/reset-more:
t7111: check that reset options work as described in the tables
Documentation: reset: add some missing tables
Fix bit assignment for CE_CONFLICTED
"reset --merge": fix unmerged case
reset: use "unpack_trees()" directly instead of "git read-tree"
reset: add a few tests for "git reset --merge"
Documentation: reset: add some tables to describe the different options
reset: improve mixed reset error message when in a bare repo
* nd/sparse: (25 commits)
t7002: test for not using external grep on skip-worktree paths
t7002: set test prerequisite "external-grep" if supported
grep: do not do external grep on skip-worktree entries
commit: correctly respect skip-worktree bit
ie_match_stat(): do not ignore skip-worktree bit with CE_MATCH_IGNORE_VALID
tests: rename duplicate t1009
sparse checkout: inhibit empty worktree
Add tests for sparse checkout
read-tree: add --no-sparse-checkout to disable sparse checkout support
unpack-trees(): ignore worktree check outside checkout area
unpack_trees(): apply $GIT_DIR/info/sparse-checkout to the final index
unpack-trees(): "enable" sparse checkout and load $GIT_DIR/info/sparse-checkout
unpack-trees.c: generalize verify_* functions
unpack-trees(): add CE_WT_REMOVE to remove on worktree alone
Introduce "sparse checkout"
dir.c: export excluded_1() and add_excludes_from_file_1()
excluded_1(): support exclude files in index
unpack-trees(): carry skip-worktree bit over in merged_entry()
Read .gitignore from index if it is skip-worktree
Avoid writing to buffer in add_excludes_from_file_1()
...
Conflicts:
.gitignore
Documentation/config.txt
Documentation/git-update-index.txt
Makefile
entry.c
t/t7002-grep.sh
Change the unlink_entry function to use rmdir to remove submodule
directories. Currently we try to use unlink, which will never succeed.
Of course rmdir will only succeed for empty (i.e. not checked out)
submodule directories. Behaviour if a submodule is checked out stays
essentially the same: print a warning message and keep the submodule
directory.
Signed-off-by: Peter Collingbourne <peter@pcc.me.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This makes the traversal of index be in sync with the tree traversal.
When unpack_callback() is fed a set of tree entries from trees, it
inspects the name of the entry and checks if the an index entry with
the same name could be hiding behind the current index entry, and
(1) if the name appears in the index as a leaf node, it is also
fed to the n_way_merge() callback function;
(2) if the name is a directory in the index, i.e. there are entries in
that are underneath it, then nothing is fed to the n_way_merge()
callback function;
(3) otherwise, if the name comes before the first eligible entry in the
index, the index entry is first unpacked alone.
When traverse_trees_recursive() descends into a subdirectory, the
cache_bottom pointer is moved to walk index entries within that directory.
All of these are omitted for diff-index, which does not even want to be
fed an index entry and a tree entry with D/F conflicts.
This fixes 3-way read-tree and exposes a bug in other parts of the system
in t6035, test #5. The test prepares these three trees:
O = HEAD^
100644 blob e69de29bb2 a/b-2/c/d
100644 blob e69de29bb2 a/b/c/d
100644 blob e69de29bb2 a/x
A = HEAD
100644 blob e69de29bb2 a/b-2/c/d
100644 blob e69de29bb2 a/b/c/d
100644 blob 587be6b4c3f93f93c489c0111bba5596147a26cb a/x
B = master
120000 blob a36b77384451ea1de7bd340ffca868249626bc52 a/b
100644 blob e69de29bb2 a/b-2/c/d
100644 blob e69de29bb2 a/x
With a clean index that matches HEAD, running
git read-tree -m -u --aggressive $O $A $B
now yields
120000 a36b77384451ea1de7bd340ffca868249626bc52 3 a/b
100644 e69de29bb2 0 a/b-2/c/d
100644 e69de29bb2 1 a/b/c/d
100644 e69de29bb2 2 a/b/c/d
100644 587be6b4c3f93f93c489c0111bba5596147a26cb 0 a/x
which is correct. "master" created "a/b" symlink that did not exist,
and removed "a/b/c/d" while HEAD did not do touch either path.
Before this series, read-tree did not notice the situation and resolved
addition of "a/b" and removal of "a/b/c/d" independently. If A = HEAD had
another path "a/b/c/e" added, this merge should conflict but instead it
silently resolved "a/b" and then immediately overwrote it to add
"a/b/c/e", which was quite bogus.
Tests in t1012 start to work with this.
Signed-off-by: Junio C Hamano <gitster@pobox.com>