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.
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)
When a user is registered in a Windows domain, it is really easy to
obtain the email address. So let's do that.
Suggested by Lutz Roeder.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
We do have the excellent GetUserInfoEx() function to obtain more
detailed information of the current user (if the user is part of a
Windows domain); Let's use it.
Suggested by Lutz Roeder.
To avoid the cost of loading Secur32.dll (even lazily, loading DLLs
takes a non-neglibile amount of time), we use the established technique
to load DLLs only when, and if, needed.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
On Windows, we have to emulate the fstat() call to fill out information
that takes extra effort to obtain, such as the file permissions/type.
If all we want is the file size, we can use the much cheaper
GetFileSizeEx() function (available since Windows XP).
Suggested by Philip Kelley.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Often we are mmap()ing read-only. In those cases, it is wasteful to map in
copy-on-write mode. Even worse: it can cause errors where we run out of
space in the page file.
So let's be extra careful to map files in read-only mode whenever
possible.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
It is not really helpful when a `git fetch` fails with the message:
fatal: mmap failed: No error
In the particular instance encountered by a colleague of yours truly,
the Win32 error code was ERROR_COMMITMENT_LIMIT which means that the
page file is not big enough.
Let's make the message
fatal: mmap failed: File too large
instead, which is only marginally better, but which can be associated
with the appropriate work-around: setting `core.packedGitWindowSize` to
a relatively small value.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
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>
We no longer use any of MSVCRT's stat-functions, so there's no need to
stick to a CRT-compatible 'struct stat' either.
Define and use our own POSIX-2013-compatible 'struct stat' with nanosecond-
precision file times.
Note: Due to performance issues when using git variants with different file
time resolutions, this patch does *not* yet enable nanosecond precision in
the Makefile (use 'make USE_NSEC=1').
Signed-off-by: Karsten Blees <blees@dcon.de>
fstat() is the only stat-related CRT function for which we don't have a
full replacement yet (and thus the only reason to stick with MSVCRT's
'struct stat' definition).
Fully implement fstat(), in preparation of implementing a POSIX 2013
compatible 'struct stat' with nanosecond-precision file times.
Signed-off-by: Karsten Blees <blees@dcon.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>
On Windows, there is no (single) `/etc/` directory. To address that, in
conjunction with the libgit2 project, Git for Windows introduced yet
another level of system-wide config files, located in C:\ProgramData
(and the equivalent on Windows XP).
Let's spell this out in the documentation.
This closes https://github.com/git-for-windows/git/pull/470 (because
there was no reaction in three months in that Pull Request).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Between the libgit2 and the Git for Windows project, there has been a
discussion how we could share Git configuration to avoid duplication (or
worse: skew).
Earlier, libgit2 was nice enough to just re-use Git for Windows'
C:\Program Files (x86)\Git\etc\gitconfig
but with the upcoming Git for Windows 2.x, there would be more paths to
search, as we will have 64-bit and 32-bit versions, and the
corresponding config files will be in %PROGRAMFILES%\Git\mingw64\etc and
...\mingw32\etc, respectively.
Worse: there are portable Git for Windows versions out there which live
in totally unrelated directories, still.
Therefore we came to a consensus to use `%PROGRAMDATA%\Git\config` as the
location for shared Git settings that are of wider interest than just Git
for Windows.
On XP, there is no %PROGRAMDATA%, therefore we need to use
"%ALLUSERSPROFILE%\Application Data\Git\config" in those setups.
Of course, the configuration in `%PROGRAMDATA%\Git\config` has the
widest reach, therefore it must take the lowest precedence, i.e. Git for
Windows can still override settings in its `etc/gitconfig` file.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
'git config' (--add / --unset etc.) automatically creates missing config
files. However, it fails with a misleading error message "could not lock
config file" if the parent directory doesn't exist.
Also create missing parent directories.
This is particularly important when calling
git config -f /non/existing/directory/config ...
We *must not* create the leading directories when locking a config file.
It is the caller's responsibility to ensure that the directory exists,
just like it is the caller's responsibility to call `git init` before
running repository operations.
Point in case: if we simply create all leading directories, calling
`git config user.name me` *outside* of a Git worktree will *create*
.git/!
This fixes https://github.com/git-for-windows/git/issues/643 and
https://groups.google.com/forum/#!topic/git-for-windows/fVRdnDIKVuw
[jes: prevented bogus .git/ directories from being created]
Signed-off-by: Karsten Blees <blees@dcon.de>
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>
The contract for the stat() and lstat() function is:
> stat(): stats the file pointed to by path and fills in buf.
> lstat(): is identical to stat(), except that if path is a symbolic link,
> then the link itself is stat-ed, not the file that it refers to.
stat() should always return the statistics of the file or directory a
symbolic link is pointing to. The lstat() function is used to get the
stats for the symlink. Hence the check should not be there.
Signed-off-by: Loris Chiocca <loris@chiocca.ch>
This is needed so that `_wchdir()` can be used with drive root
directories, e.g. C:\ (`_wchdir("C:")` fails to switch the directory
to the root directory).
This fixes https://github.com/msysgit/git/issues/359 (in Git for Windows
2.x only, though).
Likewise, `readlink()`'s semantics require a trailing slash for symbolic
links pointing to directories. Otherwise all checked out symbolic links
pointing to directories would be marked as modified even directly after a
fresh clone.
This fixes https://github.com/git-for-windows/git/issues/210
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Symlinks on Windows have a flag that indicates whether the target is a file
or a directory. Symlinks of wrong type simply don't work. This even affects
core Win32 APIs (e.g. DeleteFile() refuses to delete directory symlinks).
However, CreateFile() with FILE_FLAG_BACKUP_SEMANTICS doesn't seem to care.
Check the target type by first creating a tentative file symlink, opening
it, and checking the type of the resulting handle. If it is a directory,
recreate the symlink with the directory flag set.
It is possible to create symlinks before the target exists (or in case of
symlinks to symlinks: before the target type is known). If this happens,
create a tentative file symlink and postpone the directory decision: keep
a list of phantom symlinks to be processed whenever a new directory is
created in mingw_mkdir().
Limitations: This algorithm may fail if a link target changes from file to
directory or vice versa, or if the target directory is created in another
process.
Signed-off-by: Karsten Blees <blees@dcon.de>
Implement symlink() that always creates file symlinks. Fails with ENOSYS
if symlinks are disabled or unsupported.
Note: CreateSymbolicLinkW() was introduced with symlink support in Windows
Vista. For compatibility with Windows XP, we need to load it dynamically
and fail gracefully if it isnt's available.
Signed-off-by: Karsten Blees <blees@dcon.de>
Implement readlink() by reading NTFS reparse points. Works for symlinks
and directory junctions. If symlinks are disabled, fail with ENOSYS.
Signed-off-by: Karsten Blees <blees@dcon.de>
If symlinks are enabled, resolve all symlinks when changing directories,
as required by POSIX.
Note: Git's real_path() function bases its link resolution algorithm on
this property of chdir(). Unfortunately, the current directory on Windows
is limited to only MAX_PATH (260) characters. Therefore using symlinks and
long paths in combination may be problematic.
Note: GetFinalPathNameByHandleW() was introduced with symlink support in
Windows Vista. Thus, for compatibility with Windows XP, we need to load it
dynamically and behave gracefully if it isnt's available.
Signed-off-by: Karsten Blees <blees@dcon.de>
MSVCRT's _wrename() cannot rename symlinks over existing files: it returns
success without doing anything. Newer MSVCR*.dll versions probably do not
have this problem: according to CRT sources, they just call MoveFileEx()
with the MOVEFILE_COPY_ALLOWED flag.
Get rid of _wrename() and call MoveFileEx() with proper error handling.
Signed-off-by: Karsten Blees <blees@dcon.de>
_wunlink() / DeleteFileW() refuses to delete symlinks to directories. If
_wunlink() fails with ERROR_ACCESS_DENIED, try _wrmdir() as well.
Signed-off-by: Karsten Blees <blees@dcon.de>
Symlinks on Windows don't work the same way as on Unix systems. E.g. there
are different types of symlinks for directories and files, creating
symlinks requires administrative privileges etc.
By default, disable symlink support on Windows. I.e. users explicitly have
to enable it with 'git config [--system|--global] core.symlinks true'.
The test suite ignores system / global config files. Allow testing *with*
symlink support by checking if native symlinks are enabled in MSys2 (via
'MSYS=winsymlinks:nativestrict').
Reminder: This would need to be changed if / when we find a way to run the
test suite in a non-MSys-based shell (e.g. dash).
Signed-off-by: Karsten Blees <blees@dcon.de>
The retry pattern is duplicated in three places. It also seems to be too
hard to use: mingw_unlink() and mingw_rmdir() duplicate the code to retry,
and both of them do so incompletely. They also do not restore errno if the
user answers 'no'.
Introduce a retry_ask_yes_no() helper function that handles retry with
small delay, asking the user, and restoring errno.
mingw_unlink: include _wchmod in the retry loop (which may fail if the
file is locked exclusively).
mingw_rmdir: include special error handling in the retry loop.
Signed-off-by: Karsten Blees <blees@dcon.de>
Dynamic loading of DLL functions is duplicated in several places.
Add a set of macros to simplify the process.
Signed-off-by: Karsten Blees <blees@dcon.de>
Git typically doesn't trust the stat.st_size member of symlinks (e.g. see
strbuf_readlink()). However, some functions take shortcuts if st_size is 0
(e.g. diff_populate_filespec()).
In mingw_lstat() and fscache_lstat(), make sure to return an adequate size.
The extra overhead of opening and reading the reparse point to calculate
the exact size is not necessary, as git doesn't rely on the value anyway.
Signed-off-by: Karsten Blees <blees@dcon.de>
Move S_IFLNK detection to file_attr_to_st_mode() and reuse it in fscache.
Implement DT_LNK detection in dirent.c and the fscache readdir version.
Signed-off-by: Karsten Blees <blees@dcon.de>
When obtaining lstat information for reparse points, we need to call
FindFirstFile() in addition to GetFileInformationEx() to obtain the type
of the reparse point (symlink, mount point etc.). However, currently there
is no error handling whatsoever if FindFirstFile() fails.
Call FindFirstFile() before modifying the stat *buf output parameter and
error out if the call fails.
Note: The FindFirstFile() return value includes all the data that we get
from GetFileAttributesEx(), so we could replace GetFileAttributesEx() with
FindFirstFile(). We don't do that because GetFileAttributesEx() is about
twice as fast for single files. I.e. we only pay the extra cost of calling
FindFirstFile() in the rare case that we encounter a reparse point.
Note: The indentation of the remaining reparse point code will be fixed in
the next patch.
Signed-off-by: Karsten Blees <blees@dcon.de>
With the new mingw_stat() implementation, do_lstat() is only called from
mingw_lstat() (with follow == 0). Remove the extra function and the old
mingw_stat()-specific (follow == 1) logic.
Signed-off-by: Karsten Blees <blees@dcon.de>
