Commit Graph

54271 Commits

Author SHA1 Message Date
Thomas Braun
f9aa43d5f4 Enable support for perl regular expressions (LIBPCRE)
Signed-off-by: Thomas Braun <thomas.braun@byte-physics.de>
2015-09-29 16:45:21 +02:00
Sebastian Schuberth
3674f4c1c2 Makefile: Set htmldir to match the default HTML docs location under MSYS
Signed-off-by: Sebastian Schuberth <sschuberth@gmail.com>
2015-09-29 16:45:21 +02:00
Sebastian Schuberth
9b0bc41852 MinGW: Use MakeMaker to build the Perl libraries
This way the libraries get properly installed into the "site_perl"
directory and we just have to move them out of the "mingw" directory.

Signed-off-by: Sebastian Schuberth <sschuberth@gmail.com>
2015-09-29 16:45:21 +02:00
Johannes Schindelin
d66bce1321 Handle http.* config variables pointing to files gracefully on Windows
On Windows, we would like to be able to have a default http.sslCAinfo
that points to an MSys path (i.e. relative to the installation root of
Git).  As Git is a MinGW program, it has to handle the conversion
of the MSys path into a MinGW32 path itself.

Since system_path() considers paths starting with '/' as absolute, we
have to convince it to make a Windows path by stripping the leading
slash.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2015-09-29 16:45:20 +02:00
Johannes Schindelin
8a3c5da662 Merge pull request #93 from nalla/asciidoctor-fixes
Asciidoctor fixes

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2015-09-29 16:45:20 +02:00
Karsten Blees
33e74ae117 Win32: fix 'lstat("dir/")' with long paths
Use a suffciently large buffer to strip the trailing slash.

Signed-off-by: Karsten Blees <blees@dcon.de>
2015-09-29 16:45:20 +02:00
Karsten Blees
8433949203 Win32: support long paths
Windows paths are typically limited to MAX_PATH = 260 characters, even
though the underlying NTFS file system supports paths up to 32,767 chars.
This limitation is also evident in Windows Explorer, cmd.exe and many
other applications (including IDEs).

Particularly annoying is that most Windows APIs return bogus error codes
if a relative path only barely exceeds MAX_PATH in conjunction with the
current directory, e.g. ERROR_PATH_NOT_FOUND / ENOENT instead of the
infinitely more helpful ERROR_FILENAME_EXCED_RANGE / ENAMETOOLONG.

Many Windows wide char APIs support longer than MAX_PATH paths through the
file namespace prefix ('\\?\' or '\\?\UNC\') followed by an absolute path.
Notable exceptions include functions dealing with executables and the
current directory (CreateProcess, LoadLibrary, Get/SetCurrentDirectory) as
well as the entire shell API (ShellExecute, SHGetSpecialFolderPath...).

Introduce a handle_long_path function to check the length of a specified
path properly (and fail with ENAMETOOLONG), and to optionally expand long
paths using the '\\?\' file namespace prefix. Short paths will not be
modified, so we don't need to worry about device names (NUL, CON, AUX).

Contrary to MSDN docs, the GetFullPathNameW function doesn't seem to be
limited to MAX_PATH (at least not on Win7), so we can use it to do the
heavy lifting of the conversion (translate '/' to '\', eliminate '.' and
'..', and make an absolute path).

Add long path error checking to xutftowcs_path for APIs with hard MAX_PATH
limit.

Add a new MAX_LONG_PATH constant and xutftowcs_long_path function for APIs
that support long paths.

While improved error checking is always active, long paths support must be
explicitly enabled via 'core.longpaths' option. This is to prevent end
users to shoot themselves in the foot by checking out files that Windows
Explorer, cmd/bash or their favorite IDE cannot handle.

Test suite:
Test the case is when the full pathname length of a dir is close
to 260 (MAX_PATH).
Bug report and an original reproducer by Andrey Rogozhnikov:
https://github.com/msysgit/git/pull/122#issuecomment-43604199

[jes: adjusted test number to avoid conflicts, reinstated && chain]

Thanks-to: Martin W. Kirst <maki@bitkings.de>
Thanks-to: Doug Kelly <dougk.ff7@gmail.com>
Signed-off-by: Karsten Blees <blees@dcon.de>
Original-test-by: Andrey Rogozhnikov <rogozhnikov.andrey@gmail.com>
Signed-off-by: Stepan Kasal <kasal@ucw.cz>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2015-09-29 16:45:20 +02:00
Johannes Schindelin
9ee67738ca Win32: support long paths
Windows paths are typically limited to MAX_PATH = 260 characters, even
though the underlying NTFS file system supports paths up to 32,767 chars.
This limitation is also evident in Windows Explorer, cmd.exe and many
other applications (including IDEs).

Particularly annoying is that most Windows APIs return bogus error codes
if a relative path only barely exceeds MAX_PATH in conjunction with the
current directory, e.g. ERROR_PATH_NOT_FOUND / ENOENT instead of the
infinitely more helpful ERROR_FILENAME_EXCED_RANGE / ENAMETOOLONG.

Many Windows wide char APIs support longer than MAX_PATH paths through the
file namespace prefix ('\\?\' or '\\?\UNC\') followed by an absolute path.
Notable exceptions include functions dealing with executables and the
current directory (CreateProcess, LoadLibrary, Get/SetCurrentDirectory) as
well as the entire shell API (ShellExecute, SHGetSpecialFolderPath...).

Introduce a handle_long_path function to check the length of a specified
path properly (and fail with ENAMETOOLONG), and to optionally expand long
paths using the '\\?\' file namespace prefix. Short paths will not be
modified, so we don't need to worry about device names (NUL, CON, AUX).

Contrary to MSDN docs, the GetFullPathNameW function doesn't seem to be
limited to MAX_PATH (at least not on Win7), so we can use it to do the
heavy lifting of the conversion (translate '/' to '\', eliminate '.' and
'..', and make an absolute path).

Add long path error checking to xutftowcs_path for APIs with hard MAX_PATH
limit.

Add a new MAX_LONG_PATH constant and xutftowcs_long_path function for APIs
that support long paths.

While improved error checking is always active, long paths support must be
explicitly enabled via 'core.longpaths' option. This is to prevent end
users to shoot themselves in the foot by checking out files that Windows
Explorer, cmd/bash or their favorite IDE cannot handle.

Test suite:
Test the case is when the full pathname length of a dir is close
to 260 (MAX_PATH).
Bug report and an original reproducer by Andrey Rogozhnikov:
https://github.com/msysgit/git/pull/122#issuecomment-43604199

[jes: adjusted test number to avoid conflicts]

Thanks-to: Martin W. Kirst <maki@bitkings.de>
Thanks-to: Doug Kelly <dougk.ff7@gmail.com>
Signed-off-by: Karsten Blees <blees@dcon.de>
Original-test-by: Andrey Rogozhnikov <rogozhnikov.andrey@gmail.com>
Signed-off-by: Stepan Kasal <kasal@ucw.cz>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2015-09-29 16:45:20 +02:00
Doug Kelly
2897175ee2 Add a test demonstrating a problem with long submodule paths
[jes: adusted test number to avoid conflicts, fixed non-portable use of
the 'export' statement]

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2015-09-29 16:45:20 +02:00
Karsten Blees
923e6033c6 fscache: load directories only once
If multiple threads access a directory that is not yet in the cache, the
directory will be loaded by each thread. Only one of the results is added
to the cache, all others are leaked. This wastes performance and memory.

On cache miss, add a future object to the cache to indicate that the
directory is currently being loaded. Subsequent threads register themselves
with the future object and wait. When the first thread has loaded the
directory, it replaces the future object with the result and notifies
waiting threads.

Signed-off-by: Karsten Blees <blees@dcon.de>
2015-09-29 16:45:20 +02:00
Karsten Blees
320ffb6762 Win32: add a cache below mingw's lstat and dirent implementations
Checking the work tree status is quite slow on Windows, due to slow lstat
emulation (git calls lstat once for each file in the index). Windows
operating system APIs seem to be much better at scanning the status
of entire directories than checking single files.

Add an lstat implementation that uses a cache for lstat data. Cache misses
read the entire parent directory and add it to the cache. Subsequent lstat
calls for the same directory are served directly from the cache.

Also implement opendir / readdir / closedir so that they create and use
directory listings in the cache.

The cache doesn't track file system changes and doesn't plug into any
modifying file APIs, so it has to be explicitly enabled for git functions
that don't modify the working copy.

Note: in an earlier version of this patch, the cache was always active and
tracked file system changes via ReadDirectoryChangesW. However, this was
much more complex and had negative impact on the performance of modifying
git commands such as 'git checkout'.

Signed-off-by: Karsten Blees <blees@dcon.de>
2015-09-29 16:45:20 +02:00
Karsten Blees
abf4bf5fdb add infrastructure for read-only file system level caches
Add a macro to mark code sections that only read from the file system,
along with a config option and documentation.

This facilitates implementation of relatively simple file system level
caches without the need to synchronize with the file system.

Enable read-only sections for 'git status' and preload_index.

Signed-off-by: Karsten Blees <blees@dcon.de>
2015-09-29 16:45:20 +02:00
Johannes Schindelin
c90142047a Teach 'git remote' that the config var branch.*.rebase can be 'interactive'
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2015-09-29 16:45:19 +02:00
nalla
fddc760f31 asciidoctor: Fix giteveryday.txt to be built with asciidoctor.
When building the `doc` with `asciidoctor`, `asciidoctor` complains about
a nested code block in a callout list. This is a really dirty solution to
restore the callout list to function properly. There is a minimal visual
sideeffect; the *immitated* codeblock has no overall greyish background.
Instead the individual lines have it.

Note: When building this patch with `asciidoc` the background is totally
gone but the font is still monospaced.

Signed-off-by: nalla <nalla@hamal.uberspace.de>
2015-09-29 16:45:19 +02:00
Karsten Blees
8011810ea1 Win32: make the lstat implementation pluggable
Emulating the POSIX lstat API on Windows via GetFileAttributes[Ex] is quite
slow. Windows operating system APIs seem to be much better at scanning the
status of entire directories than checking single files. A caching
implementation may improve performance by bulk-reading entire directories
or reusing data obtained via opendir / readdir.

Make the lstat implementation pluggable so that it can be switched at
runtime, e.g. based on a config option.

Signed-off-by: Karsten Blees <blees@dcon.de>
2015-09-29 16:45:19 +02:00
nalla
e614ed040b asciidoctor: Fix user-manual to be built by asciidoctor
The `user-manual.txt` ist designed as a `book` but the `Makefile` wants to
build it as an `article`. This seems to be a problem when building the
documentation with `asciidoctor`. Furthermore the parts *Git Glossary*
and *Apendix B* had no subsections which is not allowed when building with
`asciidoctor`. So lets add a *dummy* section.

Signed-off-by: nalla <nalla@hamal.uberspace.de>
2015-09-29 16:45:19 +02:00
Karsten Blees
4c8afdef00 Win32: Make the dirent implementation pluggable
Emulating the POSIX dirent API on Windows via FindFirstFile/FindNextFile is
pretty staightforward, however, most of the information provided in the
WIN32_FIND_DATA structure is thrown away in the process. A more
sophisticated implementation may cache this data, e.g. for later reuse in
calls to lstat.

Make the dirent implementation pluggable so that it can be switched at
runtime, e.g. based on a config option.

Define a base DIR structure with pointers to readdir/closedir that match
the opendir implementation (i.e. similar to vtable pointers in OOP).
Define readdir/closedir so that they call the function pointers in the DIR
structure. This allows to choose the opendir implementation on a
call-by-call basis.

Move the fixed sized dirent.d_name buffer to the dirent-specific DIR
structure, as d_name may be implementation specific (e.g. a caching
implementation may just set d_name to point into the cache instead of
copying the entire file name string).

Signed-off-by: Karsten Blees <blees@dcon.de>
2015-09-29 16:45:19 +02:00
Karsten Blees
14f1b799f3 Win32: dirent.c: Move opendir down
Move opendir down in preparation for the next patch.

Signed-off-by: Karsten Blees <blees@dcon.de>
2015-09-29 16:45:19 +02:00
Karsten Blees
eb653d624b Win32: make FILETIME conversion functions public
Signed-off-by: Karsten Blees <blees@dcon.de>
2015-09-29 16:45:19 +02:00
Jakub Bereżański
34174d2594 wincred: handle empty username/password correctly
Empty (length 0) usernames and/or passwords, when saved in the Windows
Credential Manager, come back as null when reading the credential.

One use case for such empty credentials is with NTLM authentication, where
empty username and password instruct libcurl to authenticate using the
credentials of the currently logged-on user (single sign-on).

When locating the relevant credentials, make empty username match null.
When outputting the credentials, handle nulls correctly.

Signed-off-by: Jakub Bereżański <kuba@berezanscy.pl>
2015-09-29 16:45:18 +02:00
Johannes Schindelin
a5aad51ef5 Handle the branch.<name>.rebase value 'interactive'
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2015-09-29 16:45:18 +02:00
Jakub Bereżański
73ac40062b t0302: check helper can handle empty credentials
Make sure the helper does not crash when blank username and password is
provided. If the helper can save such credentials, it should be able to
read them back.

Signed-off-by: Jakub Bereżański <kuba@berezanscy.pl>
2015-09-29 16:45:18 +02:00
Johannes Schindelin
854928a13d Teach 'git pull' to handle --rebase=interactive
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2015-09-29 16:45:18 +02:00
Sebastian Schuberth
c1d58dc332 gitk: Use an external icon file on Windows
Git for Windows now ships with the new Git icon from git-scm.com. Use that
icon file if it exists instead of the old procedurally drawn one.

This patch was sent upstream but so far no decision on its inclusion was
made, so commit it to our fork.

Signed-off-by: Sebastian Schuberth <sschuberth@gmail.com>
2015-09-29 16:45:06 +02:00
Johannes Schindelin
74b7b9140f git gui: set GIT_ASKPASS=git-gui--askpass if not set yet
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2015-09-29 16:38:10 +02:00
Chris West (Faux)
f35e9e3b6c Fix another invocation of git from gitk with an overly long command-line
Signed-off-by: Sebastian Schuberth <sschuberth@gmail.com>
2015-09-29 16:38:10 +02:00
Heiko Voigt
84dee06de1 git-gui: provide question helper for retry fallback on Windows
Make use of the new environment variable GIT_ASK_YESNO to support the
recently implemented fallback in case unlink, rename or rmdir fail for
files in use on Windows. The added dialog will present a yes/no question
to the the user which will currently be used by the windows compat layer
to let the user retry a failed file operation.

Signed-off-by: Heiko Voigt <hvoigt@hvoigt.net>
2015-09-29 16:38:10 +02:00
Johannes Schindelin
9f8093e073 Work around the command line limit on Windows
On Windows, there are dramatic problems when a command line grows
beyond PATH_MAX, which is restricted to 8191 characters on XP and
later (according to http://support.microsoft.com/kb/830473).

Work around this by just cutting off the command line at that length
(actually, at a space boundary) in the hope that only negative
refs are chucked: gitk will then do unnecessary work, but that is
still better than flashing the gitk window and exiting with exit
status 5 (which no Windows user is able to make sense of).

The first fix caused Tcl to fail to compile the regexp, see msysGit issue
427. Here is another fix without using regexp, and using a more relaxed
command line length limit to fix the original issue 387.

Signed-off-by: Sebastian Schuberth <sschuberth@gmail.com>
Signed-off-by: Pat Thoyts <patthoyts@users.sourceforge.net>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2015-09-29 16:38:10 +02:00
Heiko Voigt
382bb8e8de Revert "git-gui: set GIT_DIR and GIT_WORK_TREE after setup"
This reverts commit a9fa11fe5b.
2015-09-29 16:38:10 +02:00
Johannes Sixt
b2987427fa criss cross rename failure workaround
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2015-09-29 16:38:09 +02:00
Pat Thoyts
2a1b6cdd79 mingw: add tests for the hidden attribute on the git directory
With msysGit the .git directory is supposed to be hidden, unless it is
a bare git repository. Test this.

Signed-off-by: Pat Thoyts <patthoyts@users.sourceforge.net>
2015-09-29 16:38:09 +02:00
Johannes Schindelin
e881ed804b When initializing .git/, record the current setting of core.hideDotFiles
This is on Windows only, of course.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2015-09-29 16:38:09 +02:00
Erik Faye-Lund
79e10ef902 core.hideDotFiles: hide '.git' dir by default
At least for cross-platform projects, it makes sense to hide the
files starting with a dot, as this is the behavior on Unix/MacOSX.

However, at least Eclipse has problems interpreting the hidden flag
correctly, so the default is to hide only the .git/ directory.

The config setting core.hideDotFiles therefore supports not only
'true' and 'false', but also 'dotGitOnly'.

[jes: clarified the commit message, made git init respect the setting
by marking the .git/ directory only after reading the config, and added
documentation, and rebased on top of current junio/next]

Signed-off-by: Erik Faye-Lund <kusmabite@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2015-09-29 16:38:09 +02:00
Johannes Schindelin
b3b8b31882 Start the merging-rebase to v2.6.0
This commit starts the rebase of 043706f to 17f9f63
2015-09-29 16:38:08 +02:00
Karsten Blees
01bf933738 git-gui:handle the encoding of Git's output correctly
If we use 'eval exec $opt $cmdp $args' to execute git command,
tcl engine will convert the output of the git comand with the rule
system default code page to unicode.

But cp936 -> unicode conversion implicitly done by exec is not reversible.
So we have to use git_read instead.

Bug report and an original reproducer by Cloud Chou:
https://github.com/msysgit/git/issues/302

Karsten Blees writes this code patch.
Cloud Chou find the reason of the bug.

Thanks-to: dscho
Thanks-to: patthoyts
Signed-off-by: Karsten Blees <blees@dcon.de>
Original-test-by: Cloud Chou <515312382@qq.com>
Signed-off-by: Cloud Chou <515312382@qq.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2015-09-29 16:38:08 +02:00
Karsten Blees
928a4cd8e3 Unicode file name support (gitk and git-gui)
Assumes file names in git tree objects are UTF-8 encoded.

On most unix systems, the system encoding (and thus the TCL system
encoding) will be UTF-8, so file names will be displayed correctly.

On Windows, it is impossible to set the system encoding to UTF-8. Changing
the TCL system encoding (via 'encoding system ...', e.g. in the startup
code) is explicitly discouraged by the TCL docs.

Change gitk and git-gui functions dealing with file names to always convert
from and to UTF-8.

Signed-off-by: Karsten Blees <blees@dcon.de>
2015-09-29 16:38:08 +02:00
Johannes Schindelin
a9809b1615 Merge branch 'home-bin' 2015-09-29 14:12:37 +00:00
Johannes Schindelin
41907c3661 git-wrapper: append $HOME/bin to the PATH
`$HOME/bin/` is quite convenient a place to put user-specific Git
helpers, such as credential or remote helpers.

When run in Git Bash, it is therefore already appended to the PATH;
Let's do the equivalent when run in Git CMD: when `git.exe` is
called, Git is told to look also for scripts and programs in
`$HOME/bin` (this does not modify Git CMD's `PATH`, of course).

This fixes https://github.com/git-for-windows/git/issues/429

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2015-09-29 14:09:00 +00:00
Junio C Hamano
22f698cb18 Git 2.6.1
Signed-off-by: Junio C Hamano <gitster@pobox.com>
v2.6.1
2015-09-28 19:19:34 -07:00
Junio C Hamano
3adc4ec7b9 Sync with v2.5.4 2015-09-28 19:16:54 -07:00
Junio C Hamano
24358560c3 Git 2.5.4
Signed-off-by: Junio C Hamano <gitster@pobox.com>
v2.5.4
2015-09-28 15:34:28 -07:00
Junio C Hamano
11a458befc Sync with 2.4.10 2015-09-28 15:33:56 -07:00
Junio C Hamano
a2558fb8e1 Git 2.4.10
Signed-off-by: Junio C Hamano <gitster@pobox.com>
v2.4.10
2015-09-28 15:30:30 -07:00
Junio C Hamano
6343e2f6f2 Sync with 2.3.10 2015-09-28 15:28:31 -07:00
Junio C Hamano
18b58f707f Git 2.3.10
Signed-off-by: Junio C Hamano <gitster@pobox.com>
v2.3.10
2015-09-28 15:26:52 -07:00
Junio C Hamano
92cdfd2131 Merge branch 'jk/xdiff-memory-limits' into maint-2.3 2015-09-28 14:59:28 -07:00
Jeff King
83c4d38017 merge-file: enforce MAX_XDIFF_SIZE on incoming files
The previous commit enforces MAX_XDIFF_SIZE at the
interfaces to xdiff: xdi_diff (which calls xdl_diff) and
ll_xdl_merge (which calls xdl_merge).

But we have another direct call to xdl_merge in
merge-file.c. If it were written today, this probably would
just use the ll_merge machinery. But it predates that code,
and uses slightly different options to xdl_merge (e.g.,
ZEALOUS_ALNUM).

We could try to abstract out an xdi_merge to match the
existing xdi_diff, but even that is difficult. Rather than
simply report error, we try to treat large files as binary,
and that distinction would happen outside of xdi_merge.

The simplest fix is to just replicate the MAX_XDIFF_SIZE
check in merge-file.c.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-09-28 14:58:13 -07:00
Jeff King
dcd1742e56 xdiff: reject files larger than ~1GB
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>
2015-09-28 14:57:23 -07:00
Jeff King
3efb988098 react to errors in xdi_diff
When we call into xdiff to perform a diff, we generally lose
the return code completely. Typically by ignoring the return
of our xdi_diff wrapper, but sometimes we even propagate
that return value up and then ignore it later.  This can
lead to us silently producing incorrect diffs (e.g., "git
log" might produce no output at all, not even a diff header,
for a content-level diff).

In practice this does not happen very often, because the
typical reason for xdiff to report failure is that it
malloc() failed (it uses straight malloc, and not our
xmalloc wrapper).  But it could also happen when xdiff
triggers one our callbacks, which returns an error (e.g.,
outf() in builtin/rerere.c tries to report a write failure
in this way). And the next patch also plans to add more
failure modes.

Let's notice an error return from xdiff and react
appropriately. In most of the diff.c code, we can simply
die(), which matches the surrounding code (e.g., that is
what we do if we fail to load a file for diffing in the
first place). This is not that elegant, but we are probably
better off dying to let the user know there was a problem,
rather than simply generating bogus output.

We could also just die() directly in xdi_diff, but the
callers typically have a bit more context, and can provide a
better message (and if we do later decide to pass errors up,
we're one step closer to doing so).

There is one interesting case, which is in diff_grep(). Here
if we cannot generate the diff, there is nothing to match,
and we silently return "no hits". This is actually what the
existing code does already, but we make it a little more
explicit.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-09-28 14:57:10 -07:00
Junio C Hamano
f2df3104ce Merge branch 'jk/transfer-limit-redirection' into maint-2.3 2015-09-28 14:46:05 -07:00