Commit Graph

42403 Commits

Author SHA1 Message Date
Jeff King
9ff18faf2f fetch-pack: ignore SIGPIPE in sideband demuxer
If the other side feeds us a bogus pack, index-pack (or
unpack-objects) may die early, before consuming all of its
input. As a result, the sideband demuxer may get SIGPIPE
(racily, depending on whether our data made it into the pipe
buffer or not). If this happens and we are compiled with
pthread support, it will take down the main thread, too.

This isn't the end of the world, as the main process will
just die() anyway when it sees index-pack failed. But it
does mean we don't get a chance to say "fatal: index-pack
failed" or similar. And it also means that we racily fail
t5504, as we sometimes die() and sometimes are killed by
SIGPIPE.

So let's ignore SIGPIPE while demuxing the sideband. We are
already careful to check the return value of write(), so we
won't waste time writing to a broken pipe. The caller will
notice the error return from the async thread, though in
practice we don't even get that far, as we die() as soon as
we see that index-pack failed.

The non-sideband case is already fine; we let index-pack
read straight from the socket, so there is no SIGPIPE at
all. Technically the non-threaded async case is also OK
without this (the forked async process gets SIGPIPE), but
it's not worth distinguishing from the threaded case here.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-25 13:51:47 -08:00
Jeff King
9658846ce3 write_or_die: handle EPIPE in async threads
When write_or_die() sees EPIPE, it treats it specially by
converting it into a SIGPIPE death. We obviously cannot
ignore it, as the write has failed and the caller expects us
to die. But likewise, we cannot just call die(), because
printing any message at all would be a nuisance during
normal operations.

However, this is a problem if write_or_die() is called from
a thread. Our raised signal ends up killing the whole
process, when logically we just need to kill the thread
(after all, if we are ignoring SIGPIPE, there is good reason
to think that the main thread is expecting to handle it).

Inside an async thread, the die() code already does the
right thing, because we use our custom die_async() routine,
which calls pthread_join(). So ideally we would piggy-back
on that, and simply call:

  die_quietly_with_code(141);

or similar. But refactoring the die code to do this is
surprisingly non-trivial. The die_routines themselves handle
both printing and the decision of the exit code. Every one
of them would have to be modified to take new parameters for
the code, and to tell us to be quiet.

Instead, we can just teach write_or_die() to check for the
async case and handle it specially. We do have to build an
interface to abstract the async exit, but it's simple and
self-contained. If we had many call-sites that wanted to do
this die_quietly_with_code(), this approach wouldn't scale
as well, but we don't. This is the only place where do this
weird exit trick.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-25 13:51:45 -08:00
Lars Schneider
658df95a4a add DEVELOPER makefile knob to check for acknowledged warnings
We assume Git developers have a reasonably modern compiler and recommend
them to enable the DEVELOPER makefile knob to ensure their patches are
clear of all compiler warnings the Git core project cares about.

Enable the DEVELOPER makefile knob in the Travis-CI build.

Suggested-by: Jeff King <peff@peff.net>
Signed-off-by: Lars Schneider <larsxschneider@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-25 12:49:45 -08:00
David Turner
49386868de refs: document transaction semantics
Add some comments on ref transaction semantics to refs.h

Signed-off-by: David Turner <dturner@twopensource.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-25 12:35:31 -08:00
Jeff King
13e0b0d3dc use_pack: handle signed off_t overflow
A v2 pack index file can specify an offset within a packfile
of up to 2^64-1 bytes. On a system with a signed 64-bit
off_t, we can represent only up to 2^63-1. This means that a
corrupted .idx file can end up with a negative offset in the
pack code. Our bounds-checking use_pack function looks for
too-large offsets, but not for ones that have wrapped around
to negative. Let's do so, which fixes an out-of-bounds
access demonstrated in t5313.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-25 11:32:46 -08:00
Jeff King
47fe3f6ef0 nth_packed_object_offset: bounds-check extended offset
If a pack .idx file has a corrupted offset for an object, we
may try to access an offset in the .idx or .pack file that
is larger than the file's size.  For the .pack case, we have
use_pack() to protect us, which realizes the access is out
of bounds. But if the corrupted value asks us to look in the
.idx file's secondary 64-bit offset table, we blindly add it
to the mmap'd index data and access arbitrary memory.

We can fix this with a simple bounds-check compared to the
size we found when we opened the .idx file.

Note that there's similar code in index-pack that is
triggered only during "index-pack --verify". To support
both, we pull the bounds-check into a separate function,
which dies when it sees a corrupted file.

It would be nice if we could return an error, so that the
pack code could try to find a good copy of the object
elsewhere. Currently nth_packed_object_offset doesn't have
any way to return an error, but it could probably use "0" as
a sentinel value (since no object can start there). This is
the minimal fix, and we can improve the resilience later on
top.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-25 11:32:43 -08:00
Jeff King
a1283866ba t5313: test bounds-checks of corrupted/malicious pack/idx files
Our on-disk .pack and .idx files may reference other data by
offset. We should make sure that we are not fooled by
corrupt data into accessing memory outside of our mmap'd
boundaries.

This patch adds a series of tests for offsets found in .pack
and .idx files. For the most part we get this right, but
there are two tests of .idx files marked as failures: we do
not bounds-check offsets in the v2 index's extended offset
table, nor do we handle .idx offsets that overflow a signed
off_t.

With these tests, we should have good coverage of all
offsets found in these files. Note that this doesn't cover
.bitmap files, which may have similar bugs.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-25 11:32:41 -08:00
Johannes Schindelin
638fa623d5 git config: report when trying to modify a non-existing repo config
It is a pilot error to call `git config section.key value` outside of
any Git worktree. The message

	error: could not lock config file .git/config: No such file or
	directory

is not very helpful in that situation, though. Let's print a helpful
message instead.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-25 10:52:32 -08:00
Matthieu Moy
2f275207ce push: remove "push.default is unset" warning message
The warning was important before the 2.0 transition, and remained
important for a while after, so that new users get push.default
explicitly in their configuration and do not experience inconsistent
behavior if they ever used an older version of Git.

The warning has been there since version 1.8.0 (Oct 2012), hence we can
expect the vast majority of current Git users to have been exposed to
it, and most of them have already set push.default explicitly. The
switch from 'matching' to 'simple' was planned for 2.0 (May 2014), but
actually happened only for 2.3 (Feb 2015).

Today, the warning is mostly seen by beginners, who have not set their
push.default configuration (yet). For many of them, the warning is
confusing because it talks about concepts that they have not learned and
asks them a choice that they are not able to make yet. See for example

  http://stackoverflow.com/questions/13148066/warning-push-default-is-unset-its-implicit-value-is-changing-in-git-2-0

(1260 votes for the question, 1824 for the answer as of writing)

Remove the warning completely to avoid disturbing beginners. People who
still occasionally use an older version of Git will be exposed to the
warning through this old version.

Eventually, versions of Git without the warning will be deployed enough
and tutorials will not need to advise setting push.default anymore.

Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-25 09:56:42 -08:00
Matthieu Moy
a217f07388 README.md: move down historical explanation about the name
The explanations about why the name was chosen are secondary compared to
the description and link to the documentation.

Some consider these explanations as good computer scientists joke, but
other see it as needlessly offensive vocabulary.

This patch preserves the historical joke, but gives it less importance
by moving it to the end of the README, and makes it clear that it is a
historical explanation, that does not necessarily reflect the state of
mind of current developers.

Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-25 09:33:58 -08:00
Matthieu Moy
28513c4f56 README.md: don't call git stupid in the title
"the stupid content tracker" was true in the early days of Git, but
hardly applicable these days. "fast, scalable, distributed" describes
Git more accuralety.

Also, "stupid" can be seen as offensive by some people. Let's not use it
in the very first words of the README.

The new formulation is taken from the description of the Debian package.

Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-25 09:33:58 -08:00
Matthieu Moy
d9b297db70 README.md: move the link to git-scm.com up
The documentation available on git-scm.com is nicely formatted. It's
better to point users to it than to the source code of the
documentation.

Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-25 09:33:58 -08:00
Matthieu Moy
6164972018 README.md: add hyperlinks on filenames
Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-25 09:33:57 -08:00
Matthieu Moy
4ad21f5d59 README: use markdown syntax
This allows repository browsers like GitHub to display the content of
the file nicely formatted.

Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-25 09:33:57 -08:00
Martin Amdisen
9537f21b55 templates/hooks: fix minor typo in the sample update-hook
Signed-off-by: Martin Mosegaard Amdisen <martin.amdisen@praqma.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-25 09:32:20 -08:00
Stefan Beller
fb43e31f2b submodule: try harder to fetch needed sha1 by direct fetching sha1
When reviewing a change that also updates a submodule in Gerrit, a
common review practice is to download and cherry-pick the patch
locally to test it. However when testing it locally, the 'git
submodule update' may fail fetching the correct submodule sha1 as
the corresponding commit in the submodule is not yet part of the
project history, but also just a proposed change.

If $sha1 was not part of the default fetch, we try to fetch the $sha1
directly. Some servers however do not support direct fetch by sha1,
which leads git-fetch to fail quickly. We can fail ourselves here as
the still missing sha1 would lead to a failure later in the checkout
stage anyway, so failing here is as good as we can get.

Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-24 15:24:49 -08:00
Felipe Gonçalves Assis
44c74ecade t3034: test deprecated interface
--find-renames= and --rename-threshold= should be aliases.

Signed-off-by: Felipe Gonçalves Assis <felipegassis@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-24 14:48:55 -08:00
Felipe Gonçalves Assis
2307211349 t3034: test option to disable renames
Signed-off-by: Felipe Gonçalves Assis <felipegassis@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-24 14:48:34 -08:00
Felipe Gonçalves Assis
63651e1a13 t3034: add rename threshold tests
10ae752 (merge-recursive: option to specify rename threshold,
2010-09-27) introduced this feature but did not include any tests.

The tests use the new option --find-renames, which replaces the then
introduced and now deprecated option --rename-threshold.

Also update name and description of t3032 for consistency:
"merge-recursive options" -> "merge-recursive space options"

Signed-off-by: Felipe Gonçalves Assis <felipegassis@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-24 14:45:28 -08:00
Stefan Beller
2b56bb7a87 submodule helper list: respect correct path prefix
This is a regression introduced by 74703a1e4d (submodule: rewrite
`module_list` shell function in C, 2015-09-02).

Add a test to ensure we list the right submodule when giving a
specific pathspec.

Reported-By: Caleb Jorden <cjorden@gmail.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-24 14:33:02 -08:00
Junio C Hamano
56f37fda51 Eighth batch for 2.8
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-24 13:31:57 -08:00
Junio C Hamano
c3b1e8d851 Merge branch 'jc/am-i-v-fix'
The "v(iew)" subcommand of the interactive "git am -i" command was
broken in 2.6.0 timeframe when the command was rewritten in C.

* jc/am-i-v-fix:
  am -i: fix "v"iew
  pager: factor out a helper to prepare a child process to run the pager
  pager: lose a separate argv[]
2016-02-24 13:26:01 -08:00
Junio C Hamano
595bfefa6c Merge branch 'nd/worktree-add-B'
"git worktree add -B <branchname>" did not work.

* nd/worktree-add-B:
  worktree add -B: do the checkout test before update branch
  worktree: fix "add -B"
2016-02-24 13:26:00 -08:00
Junio C Hamano
5e57f9c3df Merge branch 'nd/exclusion-regression-fix'
Another try to add support to the ignore mechanism that lets you
say "this is excluded" and then later say "oh, no, this part (that
is a subset of the previous part) is not excluded".

* nd/exclusion-regression-fix:
  dir.c: don't exclude whole dir prematurely
  dir.c: support marking some patterns already matched
  dir.c: support tracing exclude
  dir.c: fix match_pathname()
2016-02-24 13:25:59 -08:00
Junio C Hamano
e79112d210 Merge branch 'ce/https-public-key-pinning'
You can now set http.[<url>.]pinnedpubkey to specify the pinned
public key when building with recent enough versions of libcURL.

* ce/https-public-key-pinning:
  http: implement public key pinning
2016-02-24 13:25:58 -08:00
Junio C Hamano
65ba75ba7d Merge branch 'bc/http-empty-auth'
Some authentication methods do not need username or password, but
libcurl needs some hint that it needs to perform authentication.
Supplying an empty username and password string is a valid way to
do so, but you can set the http.[<url>.]emptyAuth configuration
variable to achieve the same, if you find it cleaner.

* bc/http-empty-auth:
  http: add option to try authentication without username
2016-02-24 13:25:57 -08:00
Junio C Hamano
97c49af6a7 Merge branch 'sp/remote-curl-ssl-strerror'
Help those who debug http(s) part of the system.

* sp/remote-curl-ssl-strerror:
  remote-curl: include curl_errorstr on SSL setup failures
2016-02-24 13:25:56 -08:00
Junio C Hamano
9831e92bfa Merge branch 'jk/lose-name-path'
The "name_path" API was an attempt to reduce the need to construct
the full path out of a series of path components while walking a
tree hierarchy, but over time made less efficient because the path
needs to be flattened, e.g. to be compared with another path that
is already flat.  The API has been removed and its users have been
rewritten to simplify the overall code complexity.

* jk/lose-name-path:
  list-objects: pass full pathname to callbacks
  list-objects: drop name_path entirely
  list-objects: convert name_path to a strbuf
  show_object_with_name: simplify by using path_name()
  http-push: stop using name_path
2016-02-24 13:25:55 -08:00
Junio C Hamano
e84d5e9fa1 Merge branch 'ew/force-ipv4'
"git fetch" and friends that make network connections can now be
told to only use ipv4 (or ipv6).

* ew/force-ipv4:
  connect & http: support -4 and -6 switches for remote operations
2016-02-24 13:25:54 -08:00
Junio C Hamano
8020803f50 Merge branch 'nd/git-common-dir-fix'
"git rev-parse --git-common-dir" used in the worktree feature
misbehaved when run from a subdirectory.

* nd/git-common-dir-fix:
  rev-parse: take prefix into account in --git-common-dir
2016-02-24 13:25:53 -08:00
Junio C Hamano
e6a6a768ca Merge branch 'nd/dwim-wildcards-as-pathspecs'
"git show 'HEAD:Foo[BAR]Baz'" did not interpret the argument as a
rev, i.e. the object named by the the pathname with wildcard
characters in a tree object.

* nd/dwim-wildcards-as-pathspecs:
  get_sha1: don't die() on bogus search strings
  check_filename: tighten dwim-wildcard ambiguity
  checkout: reorder check_filename conditional
2016-02-24 13:25:52 -08:00
Felipe Gonçalves Assis
87892f605b merge-recursive: find-renames resets threshold
Make the find-renames option follow the behaviour in git-diff, where it
resets the threshold when none is given. So, for instance,
"--find-renames=25 --find-renames" should result in the default
threshold (50%) instead of 25%.

Signed-off-by: Felipe Gonçalves Assis <felipegassis@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-24 10:39:02 -08:00
John Keeping
3b1442d5d2 t9200: avoid grep on non-ASCII data
GNU grep 2.23 detects the input used in this test as binary data so it
does not work for extracting lines from a file.  We could add the "-a"
option to force grep to treat the input as text, but not all
implementations support that.  Instead, use sed to extract the desired
lines since it will always treat its input as text.

Signed-off-by: John Keeping <john@keeping.me.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-23 15:03:43 -08:00
John Keeping
0be43dedbc t8005: avoid grep on non-ASCII data
GNU grep 2.23 detects the input used in this test as binary data so it
does not work for extracting lines from a file.  We could add the "-a"
option to force grep to treat the input as text, but not all
implementations support that.  Instead, use sed to extract the desired
lines since it will always treat its input as text.

While touching these lines, modernize the test style to avoid hiding the
exit status of "git blame" and remove a space following a redirection
operator.  Also swap the order of the expected and actual output
files given to test_cmp; we compare expect and actual to show how
actual output differs from what is expected.

Signed-off-by: John Keeping <john@keeping.me.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-23 15:00:12 -08:00
Jon Griffiths
6e61449051 credential-cache--daemon: change to the socket dir on startup
Changing to the socket path stops the daemon holding open
the directory the user was in when it was started,
preventing umount from working. We're already holding open a
socket in that directory, so there's no downside.

Thanks-to: Jeff King <peff@peff.net>
Signed-off-by: Jon Griffiths <jon_p_griffiths@yahoo.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-23 14:48:03 -08:00
Matthieu Moy
f6b1fb372e Documentation/git-push: document that 'simple' is the default
The default behavior is well documented already in git-config(1), but
git-push(1) itself did not mention it at all. For users willing to learn
how "git push" works but not how to configure it, this makes the
documentation cumbersome to read.

Make the git-push(1) page self-contained by adding a short summary of
what 'push.default=simple' does, early in the page.

Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-23 13:35:10 -08:00
Patrick Steinhardt
4867f1184c xdiff/xmerge: fix memory leak in xdl_merge
When building the script for the second file that is to be merged
we have already allocated memory for data structures related to
the first file. When we encounter an error in building the second
script we only free allocated memory related to the second file
before erroring out.

Fix this memory leak by also releasing allocated memory related
to the first file.

Helped-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-23 12:58:26 -08:00
Jon Griffiths
bd93b8d9be credential-cache--daemon: disallow relative socket path
Relative socket paths are dangerous since the user cannot generally
control when the daemon starts (initially, after a timeout, kill or
crash). Since the daemon creates but does not delete the socket
directory, this could lead to spurious directory creation relative
to the users cwd.

Suggested-by: Jeff King <peff@peff.net>
Signed-off-by: Jon Griffiths <jon_p_griffiths@yahoo.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-23 12:56:27 -08:00
Jon Griffiths
a6e5e2864f credential-cache--daemon: refactor check_socket_directory
This function does an early return, and therefore has to
repeat its cleanup. We can stick the later bit of the
function into an "else" and avoid duplicating the shared
part (which will get bigger in a future patch).

Let's also rename the function to init_socket_directory. It
not only checks the directory but also creates it. Saying
"init" is more accurate.

Signed-off-by: Jon Griffiths <jon_p_griffiths@yahoo.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-23 12:56:26 -08:00
Eric Wong
7c0da37d7b tests: remove no-op full-svn-test target
git-svn has not supported GIT_SVN_NO_OPTIMIZE_COMMITS for
the "set-tree" sub-command in 9 years since commit 490f49ea58
("git-svn: remove optimized commit stuff for set-tree").

So remove this target and TSVN variable to avoid confusion.

ref: http://mid.gmane.org/56C9B7B7.7030406@f2.dion.ne.jp

Helped-by: Kazutoshi Satoda <k_satoda@f2.dion.ne.jp>
Signed-off-by: Eric Wong <normalperson@yhbt.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-23 12:55:03 -08:00
Torsten Bögershausen
817a0c7968 convert.c: correct attr_action()
df747b81 (convert.c: refactor crlf_action, 2016-02-10) introduced a
bug to "git ls-files --eol".

The "text" attribute was shown as "text eol=lf" or "text eol=crlf",
depending on core.autocrlf or core.eol.

Correct this and add test cases in t0027.

Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-23 12:53:15 -08:00
Jeff King
907681e940 xdiff: drop XDL_EMIT_COMMON
There are no more callers that use this mode, and none
likely to be added (as our xdl_merge() eliminates the common
use of it for generating 3-way merge bases).

This is effectively a revert of a9ed376 (xdiff: generate
"anti-diffs" aka what is common to two files, 2006-06-28),
though of course trying to revert that ancient commit
directly produces many textual conflicts.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-22 22:36:09 -08:00
Jeff King
b779b3a199 merge-tree: drop generate_common strategy
When merge_blobs sees an add/add conflict, it tries to
create a virtual base object for the 3-way merge that
consists of the common lines of each file. It inherited this
strategy from merge-one-file in 0c79938 (Improved three-way
blob merging code, 2006-06-28), and the point is to minimize
the size of the conflict hunks. That commit talks about "if
libxdiff were to ever grow a compatible three-way merge, it
could probably be directly plugged in".

That has long since happened. So as with merge-one-file in
the previous commit, this extra step is no longer necessary.
Our 3-way merge code is smart enough to do the minimizing
itself if we simply feed it an empty base, which is what the
more modern merge-recursive strategy already does.

Not only does this let us drop some code, but it removes an
overflow bug in generate_common_file(). We allocate a buffer
as large as the smallest of the two blobs, under the
assumption that there cannot be more common content than
what is in the smaller blob. However, xdiff may feed us
more: if neither file ends in a newline, it feeds us the
"\nNo newline at end of file" marker as common content, and
we write it into the output. If the differences between the
files are small than that string, we overflow the output
buffer.  This patch solves it by simply dropping the buggy
code entirely.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-22 22:36:07 -08:00
Jeff King
1a92e53ba3 merge-one-file: use empty blob for add/add base
When we see an add/add conflict on a file, we generate the
conflicted content by doing a 3-way merge with a "virtual"
base consisting of the common lines of the two sides. This
strategy dates back to cb93c19 (merge-one-file: use common
as base, instead of emptiness., 2005-11-09).

Back then, the next step was to call rcs merge to generate
the 3-way conflicts. Using the virtual base produced much
better results, as rcs merge does not attempt to minimize
the hunks. As a result, you'd get a conflict with the
entirety of the files on either side.

Since then, though, we've switched to using git-merge-file,
which uses xdiff's "zealous" merge. This will find the
minimal hunks even with just the simple, empty base.

Let's switch to using that empty base. It's simpler, more
efficient, and reduces our dependencies (we no longer need a
working diff binary). It's also how the merge-recursive
strategy handles this same case.

We can almost get rid of git-sh-setup's create_virtual_base,
but we don't here, for two reasons:

  1. The functions in git-sh-setup are part of our public
     interface, so it's possible somebody is depending on
     it. We'd at least need to deprecate it first.

  2. It's also used by mergetool's p4merge driver. It's
     unknown whether its 3-way merge is as capable as git's;
     if not, then it is benefiting from the function.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-22 22:36:05 -08:00
Jeff King
08c95df8fa ewah: convert to REALLOC_ARRAY, etc
Now that we're built around xmalloc and friends, we can use
helpers like REALLOC_ARRAY, ALLOC_GROW, and so on to make
the code shorter and protect against integer overflow.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-22 14:51:09 -08:00
Jeff King
fb7dbf3e7a convert ewah/bitmap code to use xmalloc
This code was originally written with the idea that it could
be spun off into its own ewah library, and uses the
overrideable ewah_malloc to do allocations.

We plug in xmalloc as our ewah_malloc, of course. But over
the years the ewah code itself has become more entangled
with git, and the return value of many ewah_malloc sites is
not checked.

Let's just drop the level of indirection and use xmalloc and
friends directly. This saves a few lines, and will let us
adapt these sites to our more advanced malloc helpers.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-22 14:51:09 -08:00
Jeff King
b1ddfb9151 diff_populate_gitlink: use a strbuf
We allocate 100 bytes to hold the "Submodule commit ..."
text. This is enough, but it's not immediately obvious that
this is the case, and we have to repeat the magic 100 twice.

We could get away with xstrfmt here, but we want to know the
size, as well, so let's use a real strbuf. And while we're
here, we can clean up the logic around size_only. It
currently sets and clears the "data" field pointlessly, and
leaves the "should_free" flag on even after we have cleared
the data.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-22 14:51:09 -08:00
Jeff King
21f9d0f6f2 transport_anonymize_url: use xstrfmt
This function uses xcalloc and two memcpy calls to
concatenate two strings. We can do this as an xstrfmt
one-liner, and then it is more clear that we are allocating
the correct amount of memory.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-22 14:51:09 -08:00
Jeff King
7eb45b5f78 git-compat-util: drop mempcpy compat code
There are no callers of this left, as the last one was
dropped in the previous patch. And there are not likely to
be new ones, as the function has been around since 2010
without gaining any new callers.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-22 14:51:09 -08:00
Jeff King
7b35eaf8c5 sequencer: simplify memory allocation of get_message
For a commit with sha1 "1234abcd" and subject "foo", this
function produces a struct with three strings:

 1. "foo"

 2. "1234abcd... foo"

 3. "parent of 1234abcd... foo"

It takes advantage of the fact that these strings are
subsets of each other, and allocates only _one_ string, with
pointers into the various parts. Unfortunately, this makes
the string allocation complicated and hard to follow.

Since we keep only one of these in memory at a time, we can
afford to simply allocate three strings. This lets us build
on tools like xstrfmt and avoid manual computation.

While we're here, we can also drop the ad-hoc
reimplementation of get_git_commit_encoding(), and simply
call that function.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-22 14:51:09 -08:00