"git rerere" can get confused by conflict markers deliberately left
by the inner merge step, because they are indistinguishable from
the real conflict markers left by the outermost merge which are
what the end user and "rerere" need to look at. This was fixed by
making the conflict markers left by the inner merges a bit longer.
* jc/ll-merge-internal:
t6036: remove pointless test that expects failure
ll-merge: use a longer conflict marker for internal merge
ll-merge: fix typo in comment
The primary use of conflict markers is to help the user who resolves
the final (outer) merge by hand to show which part came from which
branch by separating the blocks of lines apart. When the conflicted
parts from a "virtual ancestor" merge created by merge-recursive
remains in the common ancestor part in the final result, however,
the conflict markers that are the same size as the final merge
become harder to see.
Increase the conflict marker size slightly for these inner merges so
that the markers from the final merge and cruft from internal merge
can be distinguished more easily.
This would help reduce the common issue that prevents "rerere" from
being used on a really complex conflict.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When a944af1d (merge: teach -Xours/-Xtheirs to binary ll-merge
driver, 2012-09-08) introduced FAVOR_OURS/FAVOR_THEIRS to the binary
ll-merge driver, it changed what happens to the merge result for the
outer merge, and updated the comment from:
The tentative merge result is "ours" for the final round, or
common ancestor for an internal merge. Still return "conflicted
merge" status.
to
The tentative merge result is the or common ancestor for an
internal merge.
What happened is obvious. I noticed the lack of definitive article
in front of "common" but failed to remove "or". Also I forgot to
describe what I did for the final merge, probably because I was
satisified by the description in the log message.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We frequently allocate strings as xmalloc(len + 1), where
the extra 1 is for the NUL terminator. This can be done more
simply with xmallocz, which also checks for integer
overflow.
There's no case where switching xmalloc(n+1) to xmallocz(n)
is wrong; the result is the same length, and malloc made no
guarantees about what was in the buffer anyway. But in some
cases, we can stop manually placing NUL at the end of the
allocated buffer. But that's only safe if it's clear that
the contents will always fill the buffer.
In each case where this patch does so, I manually examined
the control flow, and I tried to err on the side of caution.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Many allocations that is manually counted (correctly) that are
followed by strcpy/sprintf have been replaced with a less error
prone constructs such as xstrfmt.
Macintosh-specific breakage was noticed and corrected in this
reroll.
* jk/war-on-sprintf: (70 commits)
name-rev: use strip_suffix to avoid magic numbers
use strbuf_complete to conditionally append slash
fsck: use for_each_loose_file_in_objdir
Makefile: drop D_INO_IN_DIRENT build knob
fsck: drop inode-sorting code
convert strncpy to memcpy
notes: document length of fanout path with a constant
color: add color_set helper for copying raw colors
prefer memcpy to strcpy
help: clean up kfmclient munging
receive-pack: simplify keep_arg computation
avoid sprintf and strcpy with flex arrays
use alloc_ref rather than hand-allocating "struct ref"
color: add overflow checks for parsing colors
drop strcpy in favor of raw sha1_to_hex
use sha1_to_hex_r() instead of strcpy
daemon: use cld->env_array when re-spawning
stat_tracking_info: convert to argv_array
http-push: use an argv_array for setup_revisions
fetch-pack: use argv_array for index-pack / unpack-objects
...
The xdiff code is not prepared to handle extremely large
files. It uses "int" in many places, which can overflow if
we have a very large number of lines or even bytes in our
input files. This can cause us to produce incorrect diffs,
with no indication that the output is wrong. Or worse, we
may even underallocate a buffer whose size is the result of
an overflowing addition.
We're much better off to tell the user that we cannot diff
or merge such a large file. This patch covers both cases,
but in slightly different ways:
1. For merging, we notice the large file and cleanly fall
back to a binary merge (which is effectively "we cannot
merge this").
2. For diffing, we make the binary/text distinction much
earlier, and in many different places. For this case,
we'll use the xdi_diff as our choke point, and reject
any diff there before it hits the xdiff code.
This means in most cases we'll die() immediately after.
That's not ideal, but in practice we shouldn't
generally hit this code path unless the user is trying
to do something tricky. We already consider files
larger than core.bigfilethreshold to be binary, so this
code would only kick in when that is circumvented
(either by bumping that value, or by using a
.gitattribute to mark a file as diffable).
In other words, we can avoid being "nice" here, because
there is already nice code that tries to do the right
thing. We are adding the suspenders to the nice code's
belt, so notice when it has been worked around (both to
protect the user from malicious inputs, and because it
is better to die() than generate bogus output).
The maximum size was chosen after experimenting with feeding
large files to the xdiff code. It's just under a gigabyte,
which leaves room for two obvious cases:
- a diff3 merge conflict result on files of maximum size X
could be 3*X plus the size of the markers, which would
still be only about 3G, which fits in a 32-bit int.
- some of the diff code allocates arrays of one int per
record. Even if each file consists only of blank lines,
then a file smaller than 1G will have fewer than 1G
records, and therefore the int array will fit in 4G.
Since the limit is arbitrary anyway, I chose to go under a
gigabyte, to leave a safety margin (e.g., we would not want
to overflow by allocating "(records + 1) * sizeof(int)" or
similar.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We sometimes sprintf into fixed-size buffers when we know
that the buffer is large enough to fit the input (either
because it's a constant, or because it's numeric input that
is bounded in size). Likewise with strcpy of constant
strings.
However, these sites make it hard to audit sprintf and
strcpy calls for buffer overflows, as a reader has to
cross-reference the size of the array with the input. Let's
use xsnprintf instead, which communicates to a reader that
we don't expect this to overflow (and catches the mistake in
case we do).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The interface to custom low-level merge driver was modeled to be
capable of driving programs like "merge" (from the RCS suite) that
can produce result solely by looking at three files that hold
contents of common ancestor, ours and theirs. The information we
feed to the external drivers via the command line placeholders %O,
%A, and %B were designed to be purely about contents by giving
names of the temporary files that hold these variants without
exposing the original pathname. No matter where the result goes,
merging the same three variants should produce the same result,
contents is the king, that is the Git way.
The external driver interface, however, is meant to help people to
step outside the Git worldview, and sometimes people want to know
the final path that the resulting merged contents would be stored
in. Expose this to the external drivers via a new placeholder %P.
Requested-by: Andreas Gondek
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There is one slight behavior change, previously "merge.default"
silently ignored a NULL value and didn't raise any error. But,
in the same function, all other values raise an error on a NULL
value. So to conform with other call sites in Git, a NULL value
for "merge.default" raises an error.
The the new config-set API is not very useful here, because much of
the function is dedicated to processing "merge.<name>.variable",
which the new API does not handle well. If it were for variables
like, "merge.summary", "merge.tool", and "merge.verbosity", we could
use the new API.
Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
Reviewed-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
These callers can drop some inline pointer arithmetic and
magic offset constants, making them more readable and less
error-prone (those constants had to match the lengths of
strings, but there is no automatic verification of that
fact).
The "ep" pointer (presumably for "end pointer"), which
points to the final key segment of the config variable, is
given the more standard name "key" to describe its function
rather than its derivation.
Signed-off-by: Jeff King <peff@peff.net>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git merge -Xtheirs" did not help content-level merge of binary
files; it should just take their version. Also "*.jpg binary" in
the attributes did not imply they should use the binary ll-merge
driver.
* jc/ll-merge-binary-ours:
ll-merge: warn about inability to merge binary files only when we can't
attr: "binary" attribute should choose built-in "binary" merge driver
merge: teach -Xours/-Xtheirs to binary ll-merge driver
When a path being merged is auto detected to be a binary file, we
warned "Cannot merge binary files" before switching to activate the
binary ll-merge driver. When we are merging with the -Xours/theirs
option, however, we know what the "clean" merge result is, and the
warning is inappropriate.
In addition, when the path is explicitly marked as a binary file,
this warning was not issued, even though without -Xours/theirs, we
cannot cleanly automerge such a path, which was inconsistent.
Move the warning code from ll_xdl_merge() to ll_binary_merge(), and
issue the message only when we cannot cleanly automerge.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The (discouraged) -Xours/-Xtheirs modes of merge are supposed to
give a quick and dirty way to come up with a random mixture of
cleanly merged parts and punted conflict resolution to take contents
from one side in conflicting parts. These options however were only
passed down to the low level merge driver for text.
Teach the built-in binary merge driver to notice them as well.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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>
Suggested by: Junio Hamano <gitster@pobox.com>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
As long as sizeof(struct ll_merge_options) is small, there is not
much reason not to keep a copy of the default merge options in the BSS
section. In return, we get clearer code and one less stack frame in
the opts == NULL case.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Teach the merge-recursive strategy a --patience option to use the
"patience diff" algorithm, which tends to improve results when
cherry-picking a patch that reorders functions at the same time as
refactoring them.
To support this, struct merge_options and ll_merge_options gain an
xdl_opts member, so programs can use arbitrary xdiff flags (think
"XDF_IGNORE_WHITESPACE") in a git-aware merge.
git merge and git rebase can be passed the -Xpatience option to
use this.
[jn: split from --ignore-space patch; with documentation]
Signed-off-by: Justin Frankel <justin@cockos.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Keeping track of the flag bits is proving more trouble than it's
worth. Instead, use a pointer to an options struct like most similar
APIs do.
Callers with no special requests can pass NULL to request the default
options.
Cc: Bert Wesarg <bert.wesarg@googlemail.com>
Cc: Avery Pennarun <apenwarr@gmail.com>
Helped-by: Justin Frankel <justin@cockos.com>
Helped-by: Bert Wesarg <bert.wesarg@googlemail.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a “renormalize” bit to the ll-merge options word so callers can
decide on a case-by-case basis whether the merge is likely to have
overlapped with a change in smudge/clean rules.
This reveals a few commands that have not been taking that situation
into account, though it does not fix them.
No functional change intended.
Cc: Eyvind Bernhardsen <eyvind.bernhardsen@gmail.com>
Improved-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
ll_merge() takes its options in a flag word, which has a few
advantages:
- options flags can be cheaply passed around in registers, while
an option struct passed by pointer cannot;
- callers can easily pass 0 without trouble for no options,
while an option struct passed by value would not allow that.
The downside is that code to populate and access the flag word can be
somewhat opaque. Mitigate that with a few macros.
Cc: Avery Pennarun <apenwarr@gmail.com>
Cc: Bert Wesarg <bert.wesarg@googlemail.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Currently, merging across changes in line ending normalization is
painful since files containing CRLF will conflict with normalized files,
even if the only difference between the two versions is the line
endings. Additionally, any "real" merge conflicts that exist are
obscured because every line in the file has a conflict.
Assume you start out with a repo that has a lot of text files with CRLF
checked in (A):
o---C
/ \
A---B---D
B: Add "* text=auto" to .gitattributes and normalize all files to
LF-only
C: Modify some of the text files
D: Try to merge C
You will get a ridiculous number of LF/CRLF conflicts when trying to
merge C into D, since the repository contents for C are "wrong" wrt the
new .gitattributes file.
Fix ll-merge so that the "base", "theirs" and "ours" stages are passed
through convert_to_worktree() and convert_to_git() before a three-way
merge. This ensures that all three stages are normalized in the same
way, removing from consideration differences that are only due to
normalization.
This feature is optional for now since it changes a low-level mechanism
and is not necessary for the majority of users. The "merge.renormalize"
config variable enables it.
Signed-off-by: Eyvind Bernhardsen <eyvind.bernhardsen@gmail.com>
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>
Commands using the ll_merge() function will present conflict hunks
imitating ‘diff3 -m’ output if the merge.conflictstyle configuration
option is set appropriately. Unlike ‘diff3 -m’, the output does not
include a label for the merge base on the ||||||| line of the output,
and some tools misparse the conflict hunks without that.
Add a new ancestor_label parameter to ll_merge() to give callers the
power to rectify this situation. If ancestor_label is NULL, the output
format is unchanged. All callers pass NULL for now.
Requested-by: Stefan Monnier <monnier@iro.umontreal.ca>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The labels for the three participants in a potential conflict are all
optional arguments for the xdiff merge routine; if they are NULL, then
xdl_merge() can cope by omitting the labels from its output. Move
them to the xmparam structure to allow new callers to save some
keystrokes where they are not needed.
This also has the virtue of making the xdiff merge interface more
similar to merge_trees, which might make it easier to learn.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Include the merge level, favor, and style flags into the xmparam_t struct.
This removes the bit twiddling with these three values into the one flags
parameter.
Signed-off-by: Bert Wesarg <bert.wesarg@googlemail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The current union merge driver is implemented as an post process. But the
xdl_merge code is quite capable to produce the result by itself. Therefore
move it there.
Signed-off-by: Bert Wesarg <bert.wesarg@googlemail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* jc/conflict-marker-size:
rerere: honor conflict-marker-size attribute
rerere: prepare for customizable conflict marker length
conflict-marker-size: new attribute
rerere: use ll_merge() instead of using xdl_merge()
merge-tree: use ll_merge() not xdl_merge()
xdl_merge(): allow passing down marker_size in xmparam_t
xdl_merge(): introduce xmparam_t for merge specific parameters
git_attr(): fix function signature
Conflicts:
builtin-merge-file.c
ll-merge.c
xdiff/xdiff.h
xdiff/xmerge.c
* ap/merge-backend-opts:
Document that merge strategies can now take their own options
Extend merge-subtree tests to test -Xsubtree=dir.
Make "subtree" part more orthogonal to the rest of merge-recursive.
pull: Fix parsing of -X<option>
Teach git-pull to pass -X<option> to git-merge
git merge -X<option>
git-merge-file --ours, --theirs
Conflicts:
git-compat-util.h
Teach "-X <option>" command line argument to "git merge" that is passed to
strategy implementations. "ours" and "theirs" autoresolution introduced
by the previous commit can be asked to the recursive strategy.
Signed-off-by: Avery Pennarun <apenwarr@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This can be specified to set the length of the conflict marker (usually 7)
to a non-default value per path. Only the callers of ll_merge() that are
aware of the per-path attributes are modified.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
So far we have only needed to be able to pass an option that is generic to
xdiff family of functions to this function. Extend the interface so that
we can give it merge specific parameters.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The function took (name, namelen) as its arguments, but all the public
callers wanted to pass a full string.
Demote the counted-string interface to an internal API status, and allow
public callers to just pass the string to the function.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Now that we have the use_shell feature, these callsites can
all be converted with small changes.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* js/run-command-updates:
api-run-command.txt: describe error behavior of run_command functions
run-command.c: squelch a "use before assignment" warning
receive-pack: remove unnecessary run_status report
run_command: report failure to execute the program, but optionally don't
run_command: encode deadly signal number in the return value
run_command: report system call errors instead of returning error codes
run_command: return exit code as positive value
MinGW: simplify waitpid() emulation macros
* tr/die_errno:
Use die_errno() instead of die() when checking syscalls
Convert existing die(..., strerror(errno)) to die_errno()
die_errno(): double % in strerror() output just in case
Introduce die_errno() that appends strerror(errno) to die()
As a general guideline, functions in git's code return zero to indicate
success and negative values to indicate failure. The run_command family of
functions followed this guideline. But there are actually two different
kinds of failure:
- failures of system calls;
- non-zero exit code of the program that was run.
Usually, a non-zero exit code of the program is a failure and means a
failure to the caller. Except that sometimes it does not. For example, the
exit code of merge programs (e.g. external merge drivers) conveys
information about how the merge failed, and not all exit calls are
actually failures.
Furthermore, the return value of run_command is sometimes used as exit
code by the caller.
This change arranges that the exit code of the program is returned as a
positive value, which can now be regarded as the "result" of the function.
System call failures continue to be reported as negative values.
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Put filenames into the conflict markers only when they are different.
Otherwise they are redundant information clutter.
Print the filename explicitely when warning about a binary conflict.
Signed-off-by: Martin Renold <martinxyz@gmx.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Lots of die() calls did not actually report the kind of error, which
can leave the user confused as to the real problem. Use die_errno()
where we check a system/library call that sets errno on failure, or
one of the following that wrap such calls:
Function Passes on error from
-------- --------------------
odb_pack_keep open
read_ancestry fopen
read_in_full xread
strbuf_read xread
strbuf_read_file open or strbuf_read_file
strbuf_readlink readlink
write_in_full xwrite
Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* sb/maint-1.6.0-add-config-fix:
add: allow configurations to be overriden by command line
use xstrdup, not strdup in ll-merge.c
Conflicts:
builtin-add.c
Otherwise, a fluky allocation failure would cause merge
configuration settings to be silently ignored.
Signed-off-by: Jim Meyering <meyering@redhat.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This helps to notice when something's going wrong, especially on
systems which lock open files.
I used the following criteria when selecting the code for replacement:
- it was already printing a warning for the unlink failures
- it is in a function which already printing something or is
called from such a function
- it is in a static function, returning void and the function is only
called from a builtin main function (cmd_)
- it is in a function which handles emergency exit (signal handlers)
- it is in a function which is obvously cleaning up the lockfiles
Signed-off-by: Alex Riesen <raa.lkml@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This teaches the low-level ll_xdl_merge() routine to honor
merge.conflictstyle configuration variable, so that merge-recursive
strategy can show the conflicts in the style of user's choice.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
git_config() only had a function parameter, but no callback data
parameter. This assumes that all callback functions only modify
global variables.
With this patch, every callback gets a void * parameter, and it is hoped
that this will help the libification effort.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This moves low-level merge functions out of merge-recursive.c and
places them in a new separate file, ll-merge.c
Signed-off-by: Junio C Hamano <gitster@pobox.com>
