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>
This branch helps with installing a `git-bash.exe` that uses ConHost
(i.e. the default Windows console window) instead of MinTTY.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
During the next rebase merge the clarification of the *read from the
console* command with the previous commits. Then get rid of this commit
message.
Signed-off-by: 마누엘 <nalla@hamal.uberspace.de>
When we fall back to starting the Git Bash in the regular Windows
console, we need to show said console's window... So let's introduce yet
another configuration knob for use via string resources.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Adjust the commit message with the following paragraph:
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`.
This branch wants to be merged into the git-wrapper branch; it fixes an
issue with the way we called the MSys2 terminal `mintty` from the GUI
application `git-bash.exe`.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
With a recent change in Cygwin (which is the basis of the msys2-runtime),
a GUI process desiring to launch an MSys2 executable needs to allocate a
console for the new process (otherwise the process will just hang on
Windows XP). _Git Bash_ is such a GUI process.
While at it, use correct handles when inheriting the stdin/stdout/stderr
handles: `GetStdHandle()` returns NULL for invalid handles, but the
STARTUPINFO must specify `INVALID_HANDLE_VALUE` instead.
Originally, the hope was that only this `NULL` => `INVALID_HANDLE_VALUE`
conversion would be required to fix the Windows XP issue mentioned above
(extensive debugging revealed that starting _Git Bash_ on Windows XP would
yield invalid handles for `stdin` and `stderr`, but *not* for `stdout`).
However, while _Git Bash_ eventually showed a `mintty` when not allocating
a new console, it took around one second to show it, and several seconds
to close it. So let's just include both fixes.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
With the resource-driven command-line configuration, we introduced the
option to ensure that only the PATH environment variable is edited only
minimally, i.e. only /cmd/ is added (as appropriate for _Git CMD_).
We are about to add another option, so let's refactor the equivalent of
Git's `strip_prefix()` function; It is not *quite* the same because we
have to `memmove()` the remainder to the beginning of the buffer.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
A typical setup under Windows is to set core.eol to CRLF, and text
files are marked as "text" in .gitattributes, or core.autocrlf is
set to true.
After 4d4813a5 "git blame" no longer works as expected for such a
set-up. Every line is annotated as "Not Committed Yet", even though
the working directory is clean. This is because the commit removed
the conversion in blame.c for all files, with or without CRLF in the
repo.
Having files with CRLF in the repo and core.autocrlf=input is a
temporary situation, and the files, if committed as is, will be
normalized in the repo, which _will_ be a notable change. Blaming
them with "Not Committed Yet" is the right result. Revert commit
4d4813a5 which was a misguided attempt to "solve" a non-problem.
Add two test cases in t8003 to verify the correct CRLF conversion.
Suggested-By: Stepan Kasal <kasal@ucw.cz>
Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Use msysGit's `git-wrapper` instead of the builtins. This works around
two issues:
- when the file system does not allow hard links, we would waste over
800 megabyte by having 109 copies of a multi-megabyte executable
- even when the file system allows hard links, the Windows Explorer
counts the disk usage as if it did not. Many users complained about
Git for Windows using too much space (when it actually did not). We
can easily avoid those user complaints by merging this branch.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This was originally 'pull request #330 from ethomson/poll_inftim' in
msysgit/git.
poll: honor the timeout on Win32
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
These fixes were necessary for Sverre Rabbelier's remote-hg to work,
but for some magic reason they are not necessary for the current
remote-hg. Makes you wonder how that one gets away with it.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
