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>
This prepares but does not yet implement a look-ahead in the index entries
when traverse-trees.c decides to give us tree entries in an order that
does not match what is in the index.
A case where a look-ahead in the index is necessary happens when merging
branch B into branch A while the index matches the current branch A, using
a tree O as their common ancestor, and these three trees looks like this:
O A B
t t
t-i t-i t-i
t-j t-j
t/1
t/2
The traverse_trees() function gets "t", "t-i" and "t" from trees O, A and
B first, and notices that A may have a matching "t" behind "t-i" and "t-j"
(indeed it does), and tells A to give that entry instead. After unpacking
blob "t" from tree B (as it hasn't changed since O in B and A removed it,
it will result in its removal), it descends into directory "t/".
The side that walked index in parallel to the tree traversal used to be
implemented with one pointer, o->pos, that points at the next index entry
to be processed. When this happens, the pointer o->pos still points at
"t-i" that is the first entry. We should be able to skip "t-i" and "t-j"
and locate "t/1" from the index while the recursive invocation of
traverse_trees() walks and match entries found there, and later come back
to process "t-i".
While that look-ahead is not implemented yet, this adds a flag bit,
CE_UNPACKED, to mark the entries in the index that has already been
processed. o->pos pointer has been renamed to o->cache_bottom and it
points at the first entry that may still need to be processed.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When the ancestor used to have a blob "P", your tree removed it, and the
tree you are merging with also removed it, the agressive three-way cleanly
merges to remove that blob. If the other tree added a new blob "P/Q"
while removing "P", it should also merge cleanly to remove "P" and create
"P/Q" (since neither the ancestor nor your tree could have had it, so it
is a typical "created in one").
The "aggressive" rule is not new anymore. Reword the stale comment.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Commit 9e8ecea (Add 'merge' mode to 'git reset', 2008-12-01) disallowed
"git reset --merge" when there was unmerged entries. But it wished if
unmerged entries were reset as if --hard (instead of --merge) has been
used. This makes sense because all "mergy" operations makes sure that
any path involved in the merge does not have local modifications before
starting, so resetting such a path away won't lose any information.
The previous commit changed the behavior of --merge to accept resetting
unmerged entries if they are reset to a different state than HEAD, but it
did not reset the changes in the work tree, leaving the conflict markers
in the resulting file in the work tree.
Fix it by doing three things:
- Update the documentation to match the wish of original "reset --merge"
better, namely, "An unmerged entry is a sign that the path didn't have
any local modification and can be safely resetted to whatever the new
HEAD records";
- Update read_index_unmerged(), which reads the index file into the cache
while dropping any higher-stage entries down to stage #0, not to copy
the object name from the higher stage entry. The code used to take the
object name from the a stage entry ("base" if you happened to have
stage #1, or "ours" if both sides added, etc.), which essentially meant
that you are getting random results depending on what the merge did.
The _only_ reason we want to keep a previously unmerged entry in the
index at stage #0 is so that we don't forget the fact that we have
corresponding file in the work tree in order to be able to remove it
when the tree we are resetting to does not have the path. In order to
differentiate such an entry from ordinary cache entry, the cache entry
added by read_index_unmerged() is marked as CE_CONFLICTED.
- Update merged_entry() and deleted_entry() so that they pay attention to
cache entries marked as CE_CONFLICTED. They are previously unmerged
entries, and the files in the work tree that correspond to them are
resetted away by oneway_merge() to the version from the tree we are
resetting to.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Previously CE_MATCH_IGNORE_VALID flag is used by both valid and
skip-worktree bits. While the two bits have similar behaviour, sharing
this flag means "git update-index --really-refresh" will ignore
skip-worktree while it should not. Instead another flag is
introduced to ignore skip-worktree bit, CE_MATCH_IGNORE_VALID only
applies to valid bit.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano
Jonathan Nieder
Clemens Buchacher
Nguyễn Thái Ngọc Duy
Matthieu Moy
Diane Gasselin
Brian Downing
Gary V. Vaughan
Peter Collingbourne