This merge strategy largely piggy-backs on git-merge-recursive.
When merging trees A and B, if B corresponds to a subtree of A,
B is first adjusted to match the tree structure of A, instead of
reading the trees at the same level. This adjustment is also
done to the common ancestor tree.
If you are pulling updates from git-gui repository into git.git
repository, the root level of the former corresponds to git-gui/
subdirectory of the latter. The tree object of git-gui's toplevel
is wrapped in a fake tree object, whose sole entry has name 'git-gui'
and records object name of the true tree, before being used by
the 3-way merge code.
If you are merging the other way, only the git-gui/ subtree of
git.git is extracted and merged into git-gui's toplevel.
The detection of corresponding subtree is done by comparing the
pathnames and types in the toplevel of the tree.
Heuristics galore! That's the git way ;-).
Signed-off-by: Junio C Hamano <junkio@cox.net>
* jc/index-output:
git-read-tree --index-output=<file>
_GIT_INDEX_OUTPUT: allow plumbing to output to an alternative index file.
Conflicts:
builtin-apply.c
This error message should not usually trigger, but the function
make_cache_entry() called by add_cacheinfo() can return early
without calling into refresh_cache_entry() that sets cache_errno.
Also the error message had a wrong function name reported, and
it did not say anything about which path failed either.
Signed-off-by: Junio C Hamano <junkio@cox.net>
When defined, this allows plumbing commands that update the
index (add, apply, checkout-index, merge-recursive, mv,
read-tree, rm, update-index, and write-tree) to write their
resulting index to an alternative index file while holding a
lock to the original index file. With this, git-commit that
jumps the index does not have to make an extra copy of the index
file, and more importantly, it can do the update while holding
the lock on the index.
However, I think the interface to let an environment variable
specify the output is a mistake, as shown in the documentation.
If a curious user has the environment variable set to something
other than the file GIT_INDEX_FILE points at, almost everything
will break. This should instead be a command line parameter to
tell these plumbing commands to write the result in the named
file, to prevent stupid mistakes.
Signed-off-by: Junio C Hamano <junkio@cox.net>
This patch leaves the base name in the resulting intermediate tree, to
propagate the conflict from intermediate merges up to the top-level merge.
Signed-off-by: Alex Riesen <raa.lkml@gmail.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
If the file system does not support symbolic links (core.symlinks=false),
merge-recursive must write the merged symbolic link text into a regular
file.
While we are here, fix a tiny memory leak in the if-branch that writes
real symbolic links.
Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
Signed-off-by: Junio C Hamano <junkio@cox.net>
We currently have two parallel notation for dealing with object types
in the code: a string and a numerical value. One of them is obviously
redundent, and the most used one requires more stack space and a bunch
of strcmp() all over the place.
This is an initial step for the removal of the version using a char array
found in object reading code paths. The patch is unfortunately large but
there is no sane way to split it in smaller parts without breaking the
system.
Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
Commit 3af244ca added unlink(2) before running symlink(2) to
update the working tree with the merge result, but it was
unlinking a wrong path. This resulted in loss of the path
pointed by a symlink.
Signed-off-by: Junio C Hamano <junkio@cox.net>
git-merge-recursive wants an null tree as the fake merge base
while producing the merge result tree. The null tree does not
have to be written out in the object store as it won't be part
of the result, and it is a prime example for using the new
pretend_sha1_file() function.
git-blame needs to register an arbitrary data to in-core index
while annotating a working tree file (or standard input), but
git-blame is a read-only application and the user of it could
even lack the privilege to write into the object store; it is
another good example for pretend_sha1_file().
Signed-off-by: Junio C Hamano <junkio@cox.net>
My earlier fix (8371234e) to delete renamed tracked files from the
working directory also caused merge-recursive to delete untracked
files that were in the working directory.
The problem here is merge-recursive is deleting the working directory
file without regard for which branch it was associated with. What we
really want to do during a merge is to only delete files that were
renamed by the branch we are merging into the current branch,
and that are still tracked by the current branch. These files
definitely don't belong in the working directory anymore.
Anything else is either a merge conflict (already handled in other
parts of the code) or a file that is untracked by the current branch
and thus is not even participating in the merge. Its this latter
class that must be left alone.
For this fix to work we are now assuming that the first non-base
argument passed to git-merge-recursive always corresponds to the
working directory. This is already true for all in-tree callers
of merge-recursive. This assumption is also supported by the
long time usage message of "<base> ... -- <head> <remote>", where
"<head>" is implied to be HEAD, which is generally assumed to be
the current tree-ish.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
Now that we are showing the output messages for verbosity levels
<5 after all actions have been performed (due to the progress meter
running during the actions) it can be confusing to see messages in
the present tense when the user is looking at a '100% done' message
right above them. Converting the messages to past tense will appear
more correct in this case, and shouldn't affect a developer who is
debugging the application and running it at a verbosity level >=5.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
Because large merges on slow systems can take up to a minute to
execute we should try to keep the user entertained with a progress
meter to let them know how far we have progressed through the
current merge.
The progress meter considers each entry in the in-memory index to
be a unit, which means a single recursive merge will double the
number of units in the progress meter. Files which are unmerged
after the 3-way tree merge are also considered a unit within the
progress meter.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
Buffering all message output until a merge invocation is complete is
necessary to prevent intereferring with a progress meter that would
indicate the number of files completely merged, and how many remain.
This change does not introduce a progress meter, but merely lays
the groundwork to buffer the output.
To aid debugging output buffering is only enabled if verbosity
is lower than 5. When using verbosity levels above 5 the user is
probably debugging the merge program itself and does not want to
see the output delayed, especially if they are stepping through
portions of the code in a debugger.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
Junio C Hamano <junkio@cox.net> writes:
>
> I think the output from merge-recursive can be categorized into 5
> verbosity levels:
>
> 1. "CONFLICT", "Rename", "Adding here instead due to D/F conflict"
> (outermost)
>
> 2. "Auto-merged successfully" (outermost)
>
> 3. The first "Merging X with Y".
>
> 4. outermost "Merging:\ntitle1\ntitle2".
>
> 5. outermost "found N common ancestors\nancestor1\nancestor2\n..."
> and anything from inner merge.
>
> I would prefer the default verbosity level to be 2 (that is, show
> both 1 and 2).
and this change makes it so. I think level 3 is probably pointless
as its only one line of output above level 2, but I can see how some
users may want to view it but not view the slightly more verbose
output of level 4.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
Because the output_indent always matches the call_depth value
there is no reason to pass around the call_depth to the merge
function during each recursive invocation.
This is a simple refactoring that will make the code easier to
follow later on as I start to add output verbosity controls.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
It is not available in the outermost merge, and it is only
useful for debugging merge-recursive in the inner merges.
Sergey Vlasov noticed that the old code accesses an
uninitialized location.
Signed-off-by: Junio C Hamano <junkio@cox.net>
This revamps the merge-recursive implementation following the
outline in:
Message-ID: <7v8xgileza.fsf@assigned-by-dhcp.cox.net>
There is no need to write out the index until the very end just
once from merge-recursive. Also there is no need to write out
the resulting tree object for the simple case of merging with a
single merge base.
Signed-off-by: Junio C Hamano <junkio@cox.net>
The merge-recursive implementation in C inherited the invariant
that the on-file index file is written out and later read back
after any index operations and writing trees from the original
Python implementation. But it was only because the original
implementation worked at the scripting level.
There is no need to write out the index file after handling
every path.
Signed-off-by: Alex Riesen <raa.lkml@gmail.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>
We have a number of badly checked write() calls. Often we are
expecting write() to write exactly the size we requested or fail,
this fails to handle interrupts or short writes. Switch to using
the new write_in_full(). Otherwise we at a minimum need to check
for EINTR and EAGAIN, where this is appropriate use xwrite().
Note, the changes to config handling are much larger and handled
in the next patch in the sequence.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
To support wider use cases, such as from within `git am -3`, the
merge-recursive utility needs to accept not just commit-ish but
also tree-ish as arguments on its command line.
If given a tree-ish then merge-recursive will create a virtual commit
wrapping it, with the subject of the commit set to the best name we
can derive for that tree, which is either the command line string
(probably the SHA1), or whatever string appears in GITHEAD_*.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
To permit the get_ref function to use the static better_branch_name
function to generate a string on demand I'm moving it up earlier.
The actual logic was not affected in this change.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
Displaying the SHA1 of 'their' branch (the branch being merged into
the current branch) is not nearly as friendly as just displaying
the name of that branch, especially if that branch is already local
to this repository.
git-merge now sets the environment variable 'GITHEAD_%(sha1)=%(name)'
for each argument it gets passed, making the actual input name that
resolved to the commit '%(sha1)' easily available to the invoked
merge strategy.
git-merge-recursive makes use of these environment variables when
they are available by using '%(name)' whenever it outputs the commit
identification rather than '%(sha1)'. This is most obvious in the
conflict hunks created by xdl_merge:
$ git mege sideb~1
<<<<<<< HEAD:INSTALL
Good!
=======
Oops.
>>>>>>> sideb~1:INSTALL
[jc: adjusted a test script and a minor constness glitch.]
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
When we get a line-level conflict in merge-recursive and print out
the two sides in the conflict hunk header and footer we should use
the standard extended SHA1 syntax to specify the specific blob,
as this allows the user to copy and paste the line right into
'git show' to view the complete version.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
* jc/clone:
Move "no merge candidate" warning into git-pull
Use preprocessor constants for environment variable names.
Do not create $GIT_DIR/remotes/ directory anymore.
Introduce GIT_TEMPLATE_DIR
Revert "fix testsuite: make sure they use templates freshly built from the source"
fix testsuite: make sure they use templates freshly built from the source
git-clone: lose the traditional 'no-separate-remote' layout
git-clone: lose the artificial "first" fetch refspec
git-pull: refuse default merge without branch.*.merge
git-clone: use wildcard specification for tracking branches
This is a mechanical clean-up of the way *.c files include
system header files.
(1) sources under compat/, platform sha-1 implementations, and
xdelta code are exempt from the following rules;
(2) the first #include must be "git-compat-util.h" or one of
our own header file that includes it first (e.g. config.h,
builtin.h, pkt-line.h);
(3) system headers that are included in "git-compat-util.h"
need not be included in individual C source files.
(4) "git-compat-util.h" does not have to include subsystem
specific header files (e.g. expat.h).
Signed-off-by: Junio C Hamano <junkio@cox.net>
We broke the discipline Linus set up to allow compiler help us
avoid typos in environment names in the early days of git over
time. This defines a handful preprocessor constants for
environment variable names used in relatively core parts of the
system.
I've left out variable names specific to subsystems such as HTTP
and SSL as I do not think they are big problems.
Signed-off-by: Junio C Hamano <junkio@cox.net>
* js/merge:
merge-recursive: add/add really is modify/modify with an empty base
Get rid of the dependency on RCS' merge program
merge-file: support -p and -q; fix compile warnings
Add builtin merge-file, a minimal replacement for RCS merge
xdl_merge(): fix and simplify conflict handling
xdl_merge(): fix thinko
xdl_merge(): fix an off-by-one bug
merge-recursive: use xdl_merge().
xmerge: make return value from xdl_merge() more usable.
xdiff: add xdl_merge()
Prior to 65ac6e9c3f we deleted a file
from the working directory during a merge if the file existed before
the merge started but was renamed by the branch being merged in.
This broke in 65ac6e as git-merge-recursive did not actually update
the working directory on an uncontested rename.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
Unify the handling for cases C (add/add) and D (modify/modify).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <junkio@cox.net>
* master: (42 commits)
git-svn: correctly handle packed-refs in refs/remotes/
add test case for recursive merge
git-svn: correctly display fatal() error messages
git-svn: allow dcommit to take an alternate head
git-svn: enable logging of information not supported by git
Clarify fetch error for missing objects.
Move Fink and Ports check to after config file
shortlog: fix segfault on empty authorname
shortlog: remove "[PATCH]" prefix from shortlog output
Make sure the empty tree exists when needed in merge-recursive.
Don't use memcpy when source and dest. buffers may overlap
no need to install manpages as executable
Documentation: simpler shared repository creation
shortlog: fix segfault on empty authorname
Add branch.*.merge warning and documentation update
Fix perl/ build.
git-svn: use do_switch for --follow-parent if the SVN library supports it
Fix documentation copy&paste typo
git-svn: extra error check to ensure we open a file correctly
Documentation: update git-clone man page with new behavior
...
There are some baseless merge cases where git-merge-recursive will
try to compare one of the branches against the empty tree. However
most projects won't have the empty tree object in their object database
as Git does not normally create empty tree objects. If the empty tree
object is missing then the merge process will die, as it cannot load the
object from the database. The error message may make the user think that
their database is corrupt when its actually not.
So instead we should just create the empty tree object whenever it is
needed. If the object already exists as a loose object then no harm
done. Otherwise that loose object will be pruned away later by either
git-prune or git-prune-packed.
Thanks goes to Junio for suggesting this fix.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
* jc/read-tree:
t6022: ignoring untracked files by merge-recursive when they do not matter
merge-recursive: adjust to loosened "working file clobbered" check
merge-recursive: make a few functions static.
merge-recursive: use abbreviated commit object name.
merge: loosen overcautious "working file will be lost" check.
Read the configuration in to get core.filemode value for this
particular repository.
Signed-off-by: Alex Riesen <raa.lkml@gmail.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>
The three-way merge by git-read-tree does not complain about
presense of the file in the working tree that is involved in a
merge when the merge result needs to be determined by the
caller. Adjust merge-recursive so that it makes sure that an
untracked file is not touched when the merge decides the path
should not be included in the final result.
Signed-off-by: Junio C Hamano <junkio@cox.net>
Most callers of write_sha1_file_prepare() are only interested in the
resulting hash but don't care about the returned file name or the header.
This patch adds a simple wrapper named hash_sha1_file() which does just
that, and converts potential callers.
Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <junkio@cox.net>
Like xmalloc and xrealloc xstrdup dies with a useful message if
the native strdup() implementation returns NULL rather than a
valid pointer.
I just tried to use xstrdup in new code and found it to be missing.
However I expected it to be present as xmalloc and xrealloc are
already commonly used throughout the code.
[jc: removed the part that deals with last_XXX, which I am
finding more and more dubious these days.]
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
This abstracts away the size of the hash values when copying them
from memory location to memory location, much as the introduction
of hashcmp abstracted away hash value comparsion.
A few call sites were using char* rather than unsigned char* so
I added the cast rather than open hashcpy to be void*. This is a
reasonable tradeoff as most call sites already use unsigned char*
and the existing hashcmp is also declared to be unsigned char*.
[jc: this is a follow-up patch for merge-recursive.c which is
not in "master" yet. The original was sent-in for "next" so
I splitted it out. ]
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
When the cache is dirty, and we switch the index file from temporary
to final, we want to discard the cache without complaint.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <junkio@cox.net>
It seems to be the only sane way to do it: when a two-head merge is
done, and the merge-base and one of the two branches agree, the
merge assumes that the other branch has something new.
If we start creating virtual commits from newer merge-bases, and go
back to older merge-bases, and then merge with newer commits again,
chances are that a patch is lost, _because_ the merge-base and the
head agree on it. Unlikely, yes, but it happened to me.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <junkio@cox.net>
This fixes the coolest merge ever.
[jc: with two "Oops that's not it" fixes from Johannes and Alex,
and an obvious type mismatch fix.]
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <junkio@cox.net>
Since there are no external calls left in merge-recur, we do not need
to set the environment variable GIT_INDEX_FILE all the time.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <junkio@cox.net>
Since merge-recur is in C, and uses libgit, it can call the relevant
functions directly, without writing the index file.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <junkio@cox.net>
To handle renames properly, we iterate through all file names of both
heads, the current one, and the one to be merged.
Only that there was a bug, where it was checked if the file name was present
in both heads, but the result of the check was never used. Instead, the
merge proceeded as if both heads contained that file.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <junkio@cox.net>
It would not make sense to parse a virtual commit, therefore set the
"parsed" flag to 1.
Signed-off-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Junio C Hamano <junkio@cox.net>
This could result in a nasty infinite loop, or in bogus names (it used
the strlen() of the newly allocated buffer instead of the original
buffer).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <junkio@cox.net>
There were two TODOs to remove sha_eq() and to convert users of
struct stage_data to active_cache users, but this is not possible.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <junkio@cox.net>
This contains mainly three sorts of fixes:
- get rid of small wrapper functions
- reuse the diff_filespec structure when sha1, mode & path are needed
- Junio's pedantic updates
Signed-off-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Junio C Hamano <junkio@cox.net>
This is just an update for people being interested. Alex and me were
busy with that project for a few days now. While it has progressed nicely,
there are quite a couple TODOs in merge-recursive.c, just search for "TODO".
For impatient people: yes, it passes all the tests, and yes, according
to the evil test Alex did, it is faster than the Python script.
But no, it is not yet finished. Biggest points are:
- there are still three external calls
- in the end, it should not be necessary to write the index more than once
(just before exiting)
- a lot of things can be refactored to make the code easier and shorter
BTW we cannot just plug in git-merge-tree yet, because git-merge-tree
does not handle renames at all.
This patch is meant for testing, and as such,
- it compile the program to git-merge-recur
- it adjusts the scripts and tests to use git-merge-recur instead of
git-merge-recursive
- it provides "TEST", a script to execute the tests regarding -recursive
- it inlines the changes to read-cache.c (read_cache_from(), discard_cache()
and refresh_cache_entry())
Brought to you by Alex Riesen and Dscho
Signed-off-by: Junio C Hamano <junkio@cox.net>
