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>
With respect to symlinks, the current stat() implementation is almost the
same as lstat(): except for the file type (st_mode & S_IFMT), it returns
information about the link rather than the target.
Implement stat by opening the file with as little permissions as possible
and calling GetFileInformationByHandle on it. This way, all link resoltion
is handled by the Windows file system layer.
If symlinks are disabled, use lstat() as before, but fail with ELOOP if a
symlink would have to be resolved.
Signed-off-by: Karsten Blees <blees@dcon.de>
GetFileAttributes cannot handle paths with trailing dir separator. The
current [l]stat implementation calls GetFileAttributes twice if the path
has trailing slashes (first with the original path passed to [l]stat, and
and a second time with a path copy with trailing '/' removed).
With Unicode conversion, we get the length of the path for free and also
have a (wide char) buffer that can be modified.
Remove trailing directory separators before calling the Win32 API.
Signed-off-by: Karsten Blees <blees@dcon.de>
strbuf_readlink() refuses to read link targets that exceed PATH_MAX (even
if a sufficient size was specified by the caller).
As some platforms support longer paths, remove this restriction (similar
to strbuf_getcwd()).
Signed-off-by: Karsten Blees <blees@dcon.de>
strbuf_readlink() calls readlink() twice if the hint argument specifies the
exact size of the link target (e.g. by passing stat.st_size as returned by
lstat()). This is necessary because 'readlink(..., hint) == hint' could
mean that the buffer was too small.
Use hint + 1 as buffer size to prevent this.
Signed-off-by: Karsten Blees <blees@dcon.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>
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).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.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>
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>
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>
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>
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>
MSys works very hard to convert Unix-style paths into DOS-style ones.
*Very* hard.
So hard, indeed, that
git blame -L/hello/,/green/
is translated into something like
git blame -LC:/msysgit/hello/,C:/msysgit/green/
As seen in msys_p2w in src\msys\msys\rt\src\winsup\cygwin\path.cc, line
3204ff:
case '-':
//
// here we check for POSIX paths as attributes to a POSIX switch.
//
...
seemingly absolute POSIX paths in single-letter options get expanded by
msys.dll unless they contain '=' or ';'.
So a quick and very dirty fix is to use '-L/;*evil/'. (Using an equal sign
works only when it is before a comma, so in the above example, /=*green/
would still be converted to a DOS-style path.)
Commit-message-by: Johannes Schindelin <johannes.schindelin@gmx.de>
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 git.rc is compiled into git.res, the result is actually dependent
on the architecture. That is, you cannot simply link a 32-bit git.res
into a 64-bit git.exe.
Therefore, to allow 32-bit and 64-bit builds in the same directory, we
let git.res depend on GIT-PREFIX so that it gets recompiled when
compiling for a different architecture (this works because the exec path
changes based on the architecture: /mingw32/libexec/git-core for 32-bit
and /mingw64/libexec/git-core for 64-bit).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
`GetLongPathName()` function may fail when it is unable to query
the parent directory of a path component to determine the long name
for that component. It happens, because of it uses `FindFirstFile()`
function for each next short part of path. The `FindFirstFile()`
requires `List Directory` and `Synchronize` desired access for a calling
process.
In case of lacking such permission for some part of path,
the `GetLongPathName()` returns 0 as result and `GetLastError()`
returns ERROR_ACCESS_DENIED.
`GetFinalPathNameByHandle()` function can help in such cases, because
it requires `Read Attributes` and `Synchronize` desired access to the
target path only.
The `GetFinalPathNameByHandle()` function was introduced on
`Windows Server 2008/Windows Vista`. So we need to load it dynamically.
`CreateFile()` parameters:
`lpFileName` = path to the current directory
`dwDesiredAccess` = 0 (it means `Read Attributes` and `Synchronize`)
`dwShareMode` = FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE
(it prevents `Sharing Violation`)
`lpSecurityAttributes` = NULL (default security attributes)
`dwCreationDisposition` = OPEN_EXISTING
(required to obtain a directory handle)
`dwFlagsAndAttributes` = FILE_FLAG_BACKUP_SEMANTICS
(required to obtain a directory handle)
`hTemplateFile` = NULL (when opening an existing file or directory,
`CreateFile` ignores this parameter)
The string that is returned by `GetFinalPathNameByHandle()` function
uses the \\?\ syntax. To skip the prefix and convert backslashes
to slashes, the `normalize_ntpath()` mingw function will be used.
Note: `GetFinalPathNameByHandle()` function returns a final path.
It is the path that is returned when a path is fully resolved.
For example, for a symbolic link named "C:\tmp\mydir" that points to
"D:\yourdir", the final path would be "D:\yourdir".
Signed-off-by: Anton Serbulov <aserbulov@plesk.com>
When switching the current working directory, say, in PowerShell, it is
quite possible to use a different capitalization than the one that is
recorded on disk. While doing the same in `cmd.exe` adjusts the
capitalization magically, that does not happen in PowerShell so that
`getcwd()` returns the current directory in a different way than is
recorded on disk.
Typically this creates no problems except when you call
git log .
in a subdirectory called, say, "GIT/" but you switched to "Git/" and
your `getcwd()` reports the latter, then Git won't understand that you
wanted to see the history as per the `GIT/` subdirectory but it thinks you
wanted to see the history of some directory that may have existed in the
past (but actually never did).
So let's be extra careful to adjust the capitalization of the current
directory before working with it.
Reported by a few PowerShell power users ;-)
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
On Windows, a file name containing a colon is illegal. We should
therefore expect the corresponding errno when `fopen()` is called for a
path of the form <commit>:.gitattributes.
This fixes https://github.com/git-for-windows/git/issues/255.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Accessing the Windows console through the special CONIN$ / CONOUT$ devices
doesn't work properly for non-ASCII usernames an passwords.
It also doesn't work for terminal emulators that hide the native console
window (such as mintty), and 'TERM=xterm*' is not necessarily a reliable
indicator for such terminals.
The new shell_prompt() function, on the other hand, works fine for both
MSys1 and MSys2, in native console windows as well as mintty, and properly
supports Unicode. It just needs bash on the path (for 'read -s', which is
bash-specific).
On Windows, try to use the shell to read from the terminal. If that fails
with ENOENT (i.e. bash was not found), use CONIN/OUT as fallback.
Note: To test this, create a UTF-8 credential file with non-ASCII chars,
e.g. in git-bash: 'echo url=http://täst.com > cred.txt'. Then in git-cmd,
'git credential fill <cred.txt' works (shell version), while calling git
without the git-wrapper (i.e. 'mingw64\bin\git credential fill <cred.txt')
mangles non-ASCII chars in both console output and input.
Signed-off-by: Karsten Blees <blees@dcon.de>
The `git_terminal_prompt()` function expects the terminal window to be
attached to a Win32 Console. However, this is not the case with terminal
windows other than `cmd.exe`'s, e.g. with MSys2's own `mintty`.
Non-cmd terminals such as `mintty` still have to have a Win32 Console
to be proper console programs, but have to hide the Win32 Console to
be able to provide more flexibility (such as being resizeable not only
vertically but also horizontally). By writing to that Win32 Console,
`git_terminal_prompt()` manages only to send the prompt to nowhere and
to wait for input from a Console to which the user has no access.
This commit introduces a function specifically to support `mintty` -- or
other terminals that are compatible with MSys2's `/dev/tty` emulation. We
use the `TERM` environment variable as an indicator for that: if the value
starts with "xterm" (such as `mintty`'s "xterm_256color"), we prefer to
let `xterm_prompt()` handle the user interaction.
The most prominent user of `git_terminal_prompt()` is certainly
`git-remote-https.exe`. It is an interesting use case because both
`stdin` and `stdout` are redirected when Git calls said executable, yet
it still wants to access the terminal.
When running inside a `mintty`, the terminal is not accessible to the
`git-remote-https.exe` program, though, because it is a MinGW program
and the `mintty` terminal is not backed by a Win32 console.
To solve that problem, we simply call out to the shell -- which is an
*MSys2* program and can therefore access `/dev/tty`.
Helped-by: nalla <nalla@hamal.uberspace.de>
Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
For performance reasons `stdout` is not unbuffered by default. That leads
to problems if after printing to `stdout` a read on `stdin` is performed.
For that reason interactive commands like `git clean -i` do not function
properly anymore if the `stdout` is not flushed by `fflush(stdout)` before
trying to read from `stdin`.
In the case of `git clean -i` all reads on `stdin` were preceded by a
`fflush(stdout)` call.
Signed-off-by: nalla <nalla@hamal.uberspace.de>
HOME initialization was historically duplicated in many different places,
including /etc/profile, launch scripts such as git-bash.vbs and gitk.cmd,
and (although slightly broken) in the git-wrapper.
Even unrelated projects such as GitExtensions and TortoiseGit need to
implement the same logic to be able to call git directly.
Initialize HOME in git's own startup code so that we can eventually retire
all the duplicate initialization code.
Signed-off-by: Karsten Blees <blees@dcon.de>
This developer should really, really have known better. The fact that we
are changing the environment in ways for which the MSVCRT is not
prepared for is bad enough. But then this developer followed the request
to re-enable nedmalloc -- despite the prediction that it would cause an
access violation, predicting it in the same message as the request to
re-enable nedmalloc, no less!
To paper over the issue until the time when this developer finds the
time to re-design the Unicode environment handling from scratch, let's
hope that cURL is the only library we are using that *may* set an
environment variable using MSVCRT's putenv() after we fscked the
environment up.
Note: this commit can serve as no source of pride to anyone, certainly
not yours truly. It is necessary as a quick and pragmatic stop gap,
though, to prevent worse problems.
Note: cURL manages to set the variable CHARSET when nedmalloc is *not*
enabled, without causing an access violation. In that case, it sets it
successfully to the value "cp" + GetACP() (hence it is our choice, too,
cURL may need it, Git does not):
https://github.com/bagder/curl/blob/aa5808b5/lib/easy.c#L157-L162
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
