The idea of having the Git wrapper in the /cmd/ directory is to allow
adding only a *tiny* set of executables to the search path, to allow
minimal interference with other software applications. It is quite
likely, for example, that other software applications require their own
version of zlib1.dll and would not be overly happy to find the version
Git for Windows ships.
The /cmd/ directory also gives us the opportunity to let the Git wrapper
handle the `gitk` script. It is a Tcl/Tk script that is not recognized
by Windows, therefore calling `gitk` in `cmd.exe` would not work, even
if we add all of Git for Windows' bin/ directories.
So let's use the /cmd/ directory instead of adding /mingw??/bin/ and
/usr/bin/ to the PATH when launching Git CMD.
The way we implemented Git CMD is to embed the appropriate command line
as string resource into a copy of the Git wrapper. Therefore we extended
that syntax to allow for configuring a minimal search path.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
We recently added the ability to configure copies of the Git wrapper to
launch custom command-lines, configured via plain old Windows resources.
The main user is Git for Windows' `git-bash.exe`, of course. When the
user double-clicks the `git bash` icon, it makes sense to start the Bash
in the user's home directory.
Third-party software, such as TortoiseGit or GitHub for Windows, may
want to start the Git Bash in another directory, though.
Now, when third-party software wants to call Git, they already have to
construct a command-line, and can easily pass a command-line option
`--no-cd` (which this commit introduces), and since that option is not
available when the user double-clicks an icon on the Desktop or in the
Explorer, let's keep the default to switch to the home directory if the
`--no-cd` flag was not passed along.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
When we rewrite the command-line to call the *real* Git, we want to skip
the first command-line parameter. The previous code worked in most
circumstances, but was a bit fragile because it assumed that no fancy
quoting would take place.
In the next commit, we will want to have the option to skip more than
just one command-line parameter, so we have to be much more careful with
the command-line handling.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
In the meantime, Git for Windows learned to handle those subcommands
quite well itself; There is no longer a need to special-case them in the
wrapper.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
In a push to polish Git for Windows more, we are moving away from
scripts toward proper binaries.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The Git wrapper does one thing, and does it well: setting up the
environment required to run Git and its scripts, and then hand off to
another program.
We already do this for the Git executable itself; in Git for Windows'
context, we have exactly the same need also when calling the Git Bash or
Git CMD. However, both are tied to what particular shell environment you
use, though: MSys or MSys2 (or whatever else cunning developers make
work for them). This means that the Git Bash and Git CMD need to be
compiled in the respective context (e.g. when compiling the
mingw-w64-git package in the MSys2 context).
Happily, Windows offers a way to configure compiled executables:
resources. So let's just look whether the current executable has a
string resource and use it as the command-line to execute after the
environment is set up. To support MSys2's Git Bash better (where
`mintty` should, but might not, be available), we verify whether the
specified executable exists, and keep looking for string resources if it
does not.
For even more flexibility, we expand environment variables specified as
`@@<VARIABLE-NAME>@@`, and for convenience `@@EXEPATH@@` expands into
the directory in which the executable resides.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Otherwise the output of Git commands cannot be caught by, say, Git GUI
(because it is running detached from any console, which would make
`git.exe` inherit the standard handles implicitly).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
We are about to use the Git wrapper to call the Git Bash of Git for
Windows. All the wrapper needs to do for that is to set up the
environment variables, use the home directory as working directory and
then hand off to a user-specified command-line.
We prepare the existing code for this change by introducing flags to set
up the environment variables, to launch a non-Git program, and to use
the home directory as working directory.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The original purpose of the Git wrapper is to run from inside Git for
Windows' /cmd/ directory, to allow setting up some environment variables
before Git is allowed to take over.
Due to differences in the file system layout, MSys2 requires some
changes for that to work.
In addition, we must take care to set the `MSYSTEM` environment variable
to `MINGW32` or `MINGW64`, respectively, to allow MSys2 to be configured
correctly in case Git launches a shell or Perl script.
We also need to change the `TERM` variable to `cygwin` instead of
`msys`, otherwise the pager `less.exe` (spawned e.g. by `git log`) will
simply crash with a message similar to this one:
1 [main] less 9832 cygwin_exception::open_stackdumpfile:
Dumping stack trace to less.exe.stackdump
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This reduces the disk footprint of a full Git for Windows setup
dramatically because on Windows, one cannot assume that hard links are
supported.
The net savings are calculated easily: the 32-bit `git.exe` file weighs
in with 7662 kB while the `git-wrapper.exe` file (modified to serve as a
drop-in replacement for builtins) weighs a scant 21 kB. At this point,
there are 109 builtins which results in a total of 813 MB disk space
being freed up by this commit.
Yes, that is really more than half a gigabyte.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Git started out as a bunch of separate commands, in the true Unix spirit.
Over time, more and more functionality was shared between the different
Git commands, though, so it made sense to introduce the notion of
"builtins": programs that are actually integrated into the main Git
executable.
These builtins can be called in two ways: either by specifying a
subcommand as the first command-line argument, or -- for backwards
compatibility -- by calling the Git executable hardlinked to a filename
of the form "git-<subcommand>". Example: the "log" command can be called
via "git log <parameters>" or via "git-log <parameters>". The latter
form is actually deprecated and only supported for scripts; calling
"git-log" interactively will not even work by default because the
libexec/git-core/ directory is not in the PATH.
All of this is well and groovy as long as hard links are supported.
Sadly, this is not the case in general on Windows. So it actually hurts
quite a bit when you have to fall back to copying all of git.exe's
currently 7.5MB 109 times, just for backwards compatibility.
The simple solution would be to install really trivial shell script
wrappers in place of the builtins:
for builtin in $BUILTINS
do
rm git-$builtin.exe
printf '#!/bin/sh\nexec git %s "$@"\n' $builtin > git-builtin
chmod a+x git-builtin
done
This method would work -- even on Windows because Git for Windows ships a
full-fledged Bash. However, the Windows Bash comes at a price: it needs to
spin up a full-fledged POSIX emulation layer everytime it starts.
Therefore, the shell script solution would incur a significant performance
penalty.
The best solution the Git for Windows team could come up with is to extend
the Git wrapper -- that is needed to call Git from cmd.exe anyway, and
that weighs in with a scant 19KB -- to also serve as a drop-in replacement
for the builtins so that the following workaround is satisfactory:
for builtin in $BUILTINS
do
cp git-wrapper.exe git-$builtin.exe
done
This commit allows for this, by extending the module file parsing to
turn builtin command names like `git-log.exe ...` into calls to the main
Git executable: `git.exe log ...`.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This prepares the wrapper for modifications to serve as a drop-in
replacement for the builtins.
This commit's diff is best viewed with the `-w` flag.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
We take care to embed the manifest, too, because we will modify the
wrapper in the next few commits to serve as a drop-in replacement for
the built-ins, i.e. we will want to call the wrapper under names such
as 'git-patch-id.exe', too.
To allow 32-bit and 64-bit builds in the same directory, we let
git-wrapper.o depend on GIT-PREFIX so that it gets recompiled when
compiling for a different architecture.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
On Windows, Git is faced by the challenge that it has to set up certain
environment variables before running Git under special circumstances
such as when Git is called directly from cmd.exe (i.e. outside any
Bash environment).
This source code was taken from msysGit's commit 74a198d:
https://github.com/msysgit/msysgit/blob/74a198d/src/git-wrapper/git-wrapper.c
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Enable DEP (Data Execution Prevention) and ASLR (Address Space Layout
Randomization) support. This applies to both 32bit and 64bit builds
and makes it substantially harder to exploit security holes in Git by
offering a much more unpredictable attack surface.
ASLR interferes with GDB's ability to set breakpoints. A similar issue
holds true when compiling with -O2 (in which case single-stepping is
messed up because GDB cannot map the code back to the original source
code properly). Therefore we simply enable ASLR only when an
optimization flag is present in the CFLAGS, using it as an indicator
that the developer does not want to debug in GDB anyway.
Signed-off-by: İsmail Dönmez <ismail@i10z.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This is the first step for enabling ASLR (Address Space Layout
Randomization) support. We want to enable ASLR for better protection
against exploiting security holes in Git.
The problem fixed by this commit is that `ld.exe` seems to be stripping
relocations which in turn will break ASLR support. We just make sure
it's not stripping the main executable entry.
Signed-off-by: İsmail Dönmez <ismail@i10z.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Just like we support having alternates pointing to different drives, we
want to support alternates pointing to network shares, i.e. UNC paths.
Technically, what we do in this patch is not to support UNC alternates,
but to support UNC paths when normalizing paths. But the latter implies
the former, and the former really was the motivation for this patch.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Commit 4b623d8 (MSVC: link in invalidcontinue.obj for better
POSIX compatibility, 2014-03-29) introduced invalidcontinue.obj
into the Makefile output, which was not parsed correctly by the
buildsystem. Ignore it, as it is known to Visual Studio and,
there is no matching source file.
Only substitute filenames ending with .o when generating the
source .c filename, otherwise a .cbj file may be expected.
Split the .o and .obj processing; 'make' does not produce .obj
files.
In the future there may be source files that produce .obj files
so keep the two issues (.obj files with & without source files)
separate.
Signed-off-by: Philip Oakley <philipoakley@iee.org>
Signed-off-by: Duncan Smart <duncan.smart@gmail.com>
(cherry picked from commit d01d71fe1aed67f4e3a5ab80eeadeaf525ad0846)
Git for Windows 2.x ships with an executable that starts the Git Bash
with all the environment variables and what not properly set up. It is
also adjusted according to the Terminal emulator option chosen when
installing Git for Windows (while `bash.exe --login -i` would always
launch with Windows' default console).
So let's use that executable (usually C:\Program Files\Git\git-bash.exe)
instead of `bash.exe --login -i` if its presence was detected.
This fixes https://github.com/git-for-windows/git/issues/490
Signed-off-by: Thomas Kläger <thomas.klaeger@10a.ch>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
When calling `Repository>Create Desktop Shortcut`, Git GUI assumes
that it is okay to call `wish.exe` directly on Windows. However, in
Git for Windows 2.x' context, that leaves several crucial environment
variables uninitialized, resulting in a shortcut that does not work.
To fix those environment variable woes, Git for Windows comes with a
convenient `git-gui.exe`, so let's just use it when it is available.
This fixes https://github.com/git-for-windows/git/issues/448
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
MSys2 might *look* like Cygwin, but it is *not* Cygwin... Unless it
is run with `MSYSTEM=MSYS`, that is.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Reusing cached data speeds up git-svn by quite a fair bit. However, if
the YAML module is unavailable, the caches are written to disk in an
architecture-dependent manner. That leads to problems when upgrading,
say, from 32-bit to 64-bit Git for Windows.
Let's just try to read those caches back if we detect the absence of the
YAML module and the presence of the file, and delete the file if it
could not be read back correctly.
Note that the only way to catch the error when the memoized cache could
not be read back is to put the call inside an `eval { ... }` block
because it would die otherwise; the `eval` block should also return `1`
in case of success explicitly since the function reading back the cached
data does not return an appropriate value to test for success.
This fixes https://github.com/git-for-windows/git/issues/233.
[jes: fixed the commit message, made the sign-off explicit]
Signed-off-by: Gavin Lambert <github@mirality.co.nz>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
When developing Git for Windows, we always have to ensure that we do not
break any non-Windows platforms, e.g. by introducing Windows-specific code
into the platform-independent source code.
At other times, it is necessary to test whether a bug is Windows-specific
or not, in order to send the bug report to the correct place. Having
access to a Linux-based Git comes in really handy in such a situation.
Vagrant offers a painless way to install and use a defined Linux
development environment on Windows (and other Operating Systems). We offer
a Vagrantfile to that end for two reasons:
1) To allow Windows users to gain the full power of Linux' Git
2) To offer users an easy path to verify that the issue they are about
to report is really a Windows-specific issue; otherwise they would
need to report it to git@vger.kernel.org instead.
Using it is easy: Download and install https://www.virtualbox.org/, then
download and install https://www.vagrantup.com/, then direct your
command-line window to the Git source directory containing the Vagrantfile
and run the commands:
vagrant up
vagrant ssh
See https://github.com/git-for-windows/git/wiki/Vagrant for details.
As part of switching Git for Windows' development environment from msysGit
to the MSys2-based Git SDK, this Vagrantfile was copy-edited from msysGit:
https://github.com/msysgit/msysgit/blob/0be8f2208/Vagrantfile
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Since commit 0c499ea60f the send-pack builtin uses the side-band-64k
capability if advertised by the server.
Unfortunately this breaks pushing over the dump git protocol if used
over a network connection.
The detailed reasons for this breakage are (by courtesy of Jeff Preshing,
quoted from ttps://groups.google.com/d/msg/msysgit/at8D7J-h7mw/eaLujILGUWoJ):
----------------------------------------------------------------------------
MinGW wraps Windows sockets in CRT file descriptors in order to mimic the
functionality of POSIX sockets. This causes msvcrt.dll to treat sockets as
Installable File System (IFS) handles, calling ReadFile, WriteFile,
DuplicateHandle and CloseHandle on them. This approach works well in simple
cases on recent versions of Windows, but does not support all usage patterns.
In particular, using this approach, any attempt to read & write concurrently
on the same socket (from one or more processes) will deadlock in a scenario
where the read waits for a response from the server which is only invoked after
the write. This is what send_pack currently attempts to do in the use_sideband
codepath.
----------------------------------------------------------------------------
The new config option "sendpack.sideband" allows to override the side-band-64k
capability of the server, and thus makes the dump git protocol work.
Other transportation methods like ssh and http/https still benefit from
the sideband channel, therefore the default value of "sendpack.sideband"
is still true.
Signed-off-by: Thomas Braun <thomas.braun@byte-physics.de>
The previous implementation said that the filesystem information on
Windows is not reliable to determine whether a file is executable.
To find gather this information it was peeking into the first two bytes
of a file to see whether it looks executable.
Apart from the fact that on Windows executables are usually defined as
such by their extension it lead to slow opening of help file in some
situations.
When you have virus scanner running calling open on an executable file
is a potentially expensive operation. See the following measurements (in
seconds) for example.
With virus scanner running (coldcache):
$ ./a.exe /libexec/git-core/
before open (git-add.exe): 0.000000
after open (git-add.exe): 0.412873
before open (git-annotate.exe): 0.000175
after open (git-annotate.exe): 0.397925
before open (git-apply.exe): 0.000243
after open (git-apply.exe): 0.399996
before open (git-archive.exe): 0.000147
after open (git-archive.exe): 0.397783
before open (git-bisect--helper.exe): 0.000160
after open (git-bisect--helper.exe): 0.397700
before open (git-blame.exe): 0.000160
after open (git-blame.exe): 0.399136
...
With virus scanner running (hotcache):
$ ./a.exe /libexec/git-core/
before open (git-add.exe): 0.000000
after open (git-add.exe): 0.000325
before open (git-annotate.exe): 0.000229
after open (git-annotate.exe): 0.000177
before open (git-apply.exe): 0.000167
after open (git-apply.exe): 0.000150
before open (git-archive.exe): 0.000154
after open (git-archive.exe): 0.000156
before open (git-bisect--helper.exe): 0.000132
after open (git-bisect--helper.exe): 0.000180
before open (git-blame.exe): 0.000718
after open (git-blame.exe): 0.000724
...
This test did just list the given directory and open() each file in it.
With this patch I get:
$ time git help git
Launching default browser to display HTML ...
real 0m8.723s
user 0m0.000s
sys 0m0.000s
and without
$ time git help git
Launching default browser to display HTML ...
real 1m37.734s
user 0m0.000s
sys 0m0.031s
both tests with cold cache and giving the machine some time to settle
down after restart.
Signed-off-by: Heiko Voigt <heiko.voigt@mahr.de>
It is better to state clearly expectations and intentions than to assume
quietly that everybody agrees.
This Code of Conduct is the Open Code of Conduct as per
http://todogroup.org/opencodeofconduct/ (the only modifications are the
adjustments to reflect that there is no "response team" in addition to the
Git for Windows maintainer, and the addition of the link to the Open Code
of Conduct itself).
[Completely revamped, based on the Covenant 1.4 by Brendan Forster]
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
7ebac8cb94 made launching of .exe
externals work when installed in Unicode paths. But it broke launching
of non-.exe externals, no matter where they were installed. We now
correctly maintain the UTF-8 and UTF-16 paths in tandem in lookup_prog.
This fixes t5526, among others.
Signed-off-by: Adam Roben <adam@roben.org>
If Git were installed in a path containing non-ASCII characters,
commands such as git-am and git-submodule, which are implemented as
externals, would fail to launch with the following error:
> fatal: 'am' appears to be a git command, but we were not
> able to execute it. Maybe git-am is broken?
This was due to lookup_prog not being Unicode-aware. It was somehow
missed in 2ee5a1a14a.
Note that the only problem in this function was calling
GetFileAttributes instead of GetFileAttributesW. The calls to access()
were fine because access() is a macro which resolves to mingw_access,
which already handles Unicode correctly. But I changed lookup_prog to
use _waccess directly so that we only convert the path to UTF-16 once.
Signed-off-by: Adam Roben <adam@roben.org>
On Windows XP3 in git bash
git clone git@github.com:octocat/Spoon-Knife.git
cd Spoon-Knife
git gui
menu Remote\Fetch from\origin
error: cannot spawn git: No such file or directory
error: could not run rev-list
if u run
git fetch --all
it worked normal in git bash or gitgui tools
In second version CreateProcess get 'C:\Git\libexec\git-core/git.exe' in
first version - C:/Git/libexec/git-core/git.exe and not executes (unix
slashes)
after fixing C:\Git\libexec\git-core\git.exe or
C:/Git/libexec/git-core\git.exe it works normal
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
After importing anything with fast-import, we should always let the
garbage collector do its job, since the objects are written to disk
inefficiently.
This brings down an initial import of http://selenic.com/hg from about
230 megabytes to about 14.
In the future, we may want to make this configurable on a per-remote
basis, or maybe teach fast-import about it in the first place.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This was probably missed because nobody had a left-over `trash/`
directory and the `-f` flag made sure that no error message was
produced when the file was not found that *actually* wanted to
be removed.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
When calling `git fast-export a..a b` when a and b refer to the same
commit, nothing would be exported, and an incorrect reset line would
be printed for b ('from :0').
Signed-off-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Sverre Rabbelier <srabbelier@gmail.com>
t0027 is marked expensive, but really, for MinGW we want to run these
tests always.
Suggested by Thomas Braun.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This happens only when the corresponding commits are not exported in
the current fast-export run. This can happen either when the relevant
commit is already marked, or when the commit is explicitly marked
as UNINTERESTING with a negative ref by another argument.
This breaks fast-export basec remote helpers.
Signed-off-by: Sverre Rabbelier <srabbelier@gmail.com>
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>
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>
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
Note that the test cannot rely on the presence of short names, as they
are not enabled by default except on the system drive.
[jes: adjusted test number to avoid conflicts, reinstated && chain,
adjusted test to work without short names]
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>
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>
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>
