The `xutftowcs_path` function canonicalizes absolute paths using GetFullPathNameW.
This canonicalization may change the length of the string (e.g. getting rid of \.\),
which breaks callers that pass the template string in a strbuf and expect the
length of the string to remain the same.
In my particular case, the tmp-objdir code is passing a strbuf to mkdtemp and is
breaking since the strbuf.len is no longer synchronized with strlen(strbuf.buf).
Signed-off-by: Neeraj K. Singh <neerajsi@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Add a basic performance test for "git add" and "git stash" of a lot of
new objects with various fsync settings.
Signed-off-by: Neeraj Singh <neerajsi@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add test cases to exercise batch mode for:
* 'git add'
* 'git stash'
* 'git update-index'
* 'git unpack-objects'
These tests ensure that the added data winds up in the object database.
In this change we introduce a new test helper lib-unique-files.sh. The
goal of this library is to create a tree of files that have different
oids from any other files that may have been created in the current test
repo. This helps us avoid missing validation of an object being added due
to it already being in the repo.
Signed-off-by: Neeraj Singh <neerajsi@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The unpack-objects functionality is used by fetch, push, and fast-import
to turn the transfered data into object database entries when there are
fewer objects than the 'unpacklimit' setting.
By enabling bulk-checkin when unpacking objects, we can take advantage
of batched fsyncs.
Signed-off-by: Neeraj Singh <neerajsi@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The update-index functionality is used internally by 'git stash push' to
setup the internal stashed commit.
This change enables bulk-checkin for update-index infrastructure to
speed up adding new objects to the object database by leveraging the
pack functionality and the new bulk-fsync functionality.
There is some risk with this change, since under batch fsync, the object
files will not be available until the update-index is entirely complete.
This usage is unlikely, since any tool invoking update-index and
expecting to see objects would have to synchronize with the update-index
process after passing it a file path.
Signed-off-by: Neeraj Singh <neerajsi@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit adds a win32 implementation for fsync_no_flush that is
called git_fsync. The 'NtFlushBuffersFileEx' function being called is
available since Windows 8. If the function is not available, we
return -1 and Git falls back to doing a full fsync.
The operating system is told to flush data only without a hardware
flush primitive. A later full fsync will cause the metadata log
to be flushed and then the disk cache to be flushed on NTFS and
ReFS. Other filesystems will treat this as a full flush operation.
I added a new file here for this system call so as not to conflict with
downstream changes in the git-for-windows repository related to fscache.
Signed-off-by: Neeraj Singh <neerajsi@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When adding many objects to a repo with core.fsyncObjectFiles set to
true, the cost of fsync'ing each object file can become prohibitive.
One major source of the cost of fsync is the implied flush of the
hardware writeback cache within the disk drive. Fortunately, Windows,
and macOS offer mechanisms to write data from the filesystem page cache
without initiating a hardware flush. Linux has the sync_file_range API,
which issues a pagecache writeback request reliably after version 5.2.
This patch introduces a new 'core.fsyncObjectFiles = batch' option that
batches up hardware flushes. It hooks into the bulk-checkin plugging and
unplugging functionality and takes advantage of tmp-objdir.
When the new mode is enabled do the following for each new object:
1. Create the object in a tmp-objdir.
2. Issue a pagecache writeback request and wait for it to complete.
At the end of the entire transaction when unplugging bulk checkin:
1. Issue an fsync against a dummy file to flush the hardware writeback
cache, which should by now have processed the tmp-objdir writes.
2. Rename all of the tmp-objdir files to their final names.
3. When updating the index and/or refs, we assume that Git will issue
another fsync internal to that operation. This is not the case today,
but may be a good extension to those components.
On a filesystem with a singular journal that is updated during name
operations (e.g. create, link, rename, etc), such as NTFS, HFS+, or XFS
we would expect the fsync to trigger a journal writeout so that this
sequence is enough to ensure that the user's data is durable by the time
the git command returns.
This change also updates the macOS code to trigger a real hardware flush
via fnctl(fd, F_FULLFSYNC) when fsync_or_die is called. Previously, on
macOS there was no guarantee of durability since a simple fsync(2) call
does not flush any hardware caches.
_Performance numbers_:
Linux - Hyper-V VM running Kernel 5.11 (Ubuntu 20.04) on a fast SSD.
Mac - macOS 11.5.1 running on a Mac mini on a 1TB Apple SSD.
Windows - Same host as Linux, a preview version of Windows 11.
This number is from a patch later in the series.
Adding 500 files to the repo with 'git add' Times reported in seconds.
core.fsyncObjectFiles | Linux | Mac | Windows
----------------------|-------|-------|--------
false | 0.06 | 0.35 | 0.61
true | 1.88 | 11.18 | 2.47
batch | 0.15 | 0.41 | 1.53
Signed-off-by: Neeraj Singh <neerajsi@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Previously, we did not install any handler for Ctrl+C, but now we really
want to because the MSYS2 runtime learned the trick to call the
ConsoleCtrlHandler when Ctrl+C was pressed.
With this, hitting Ctrl+C while `git log` is running will only terminate
the Git process, but not the pager. This finally matches the behavior on
Linux and on macOS.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Preparation for adding bulk-fsync to the bulk-checkin.c infrastructure.
* Rename 'state' variable to 'bulk_checkin_state', since we will later
be adding 'bulk_fsync_state'. This also makes the variable easier to
find in the debugger, since the name is more unique.
* Move the 'plugged' data member of 'bulk_checkin_state' into a separate
static variable. Doing this avoids resetting the variable in
finish_bulk_checkin when zeroing the 'bulk_checkin_state'. As-is, we
seem to unintentionally disable the plugging functionality the first
time a new packfile must be created due to packfile size limits. While
disabling the plugging state only results in suboptimal behavior for
the current code, it would be fatal for the bulk-fsync functionality
later in this patch series.
Signed-off-by: Neeraj Singh <neerajsi@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The Makefile target `install-mingit-test-artifacts` simply copies stuff
and things directly into a MinGit directory, including an init.bat
script to set everything up so that the tests can be run in a cmd
window.
Sadly, Git's test suite still relies on a Perl interpreter even if
compiled with NO_PERL=YesPlease. We punt for now, installing a small
script into /usr/bin/perl that hands off to an existing Perl of a Git
for Windows SDK.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The TerminateProcess() function does not actually leave the child
processes any chance to perform any cleanup operations. This is bad
insofar as Git itself expects its signal handlers to run.
A symptom is e.g. a left-behind .lock file that would not be left behind
if the same operation was run, say, on Linux.
To remedy this situation, we use an obscure trick: we inject a thread
into the process that needs to be killed and to let that thread run the
ExitProcess() function with the desired exit status. Thanks J Wyman for
describing this trick.
The advantage is that the ExitProcess() function lets the atexit
handlers run. While this is still different from what Git expects (i.e.
running a signal handler), in practice Git sets up signal handlers and
atexit handlers that call the same code to clean up after itself.
In case that the gentle method to terminate the process failed, we still
fall back to calling TerminateProcess(), but in that case we now also
make sure that processes spawned by the spawned process are terminated;
TerminateProcess() does not give the spawned process a chance to do so
itself.
Please note that this change only affects how Git for Windows tries to
terminate processes spawned by Git's own executables. Third-party
software that *calls* Git and wants to terminate it *still* need to make
sure to imitate this gentle method, otherwise this patch will not have
any effect.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
On Windows, the current working directory is pretty much guaranteed to
contain a colon. If we feed that path to CVS, it mistakes it for a
separator between host and port, though.
This has not been a problem so far because Git for Windows uses MSYS2's
Bash using a POSIX emulation layer that also pretends that the current
directory is a Unix path (at least as long as we're in a shell script).
However, that is rather limiting, as Git for Windows also explores other
ports of other Unix shells. One of those is BusyBox-w32's ash, which is
a native port (i.e. *not* using any POSIX emulation layer, and certainly
not emulating Unix paths).
So let's just detect if there is a colon in $PWD and punt in that case.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Git for Windows uses MSYS2's Bash to run the test suite, which comes
with benefits but also at a heavy price: on the plus side, MSYS2's
POSIX emulation layer allows us to continue pretending that we are on a
Unix system, e.g. use Unix paths instead of Windows ones, yet this is
bought at a rather noticeable performance penalty.
There *are* some more native ports of Unix shells out there, though,
most notably BusyBox-w32's ash. These native ports do not use any POSIX
emulation layer (or at most a *very* thin one, choosing to avoid
features such as fork() that are expensive to emulate on Windows), and
they use native Windows paths (usually with forward slashes instead of
backslashes, which is perfectly legal in almost all use cases).
And here comes the problem: with a $PWD looking like, say,
C:/git-sdk-64/usr/src/git/t/trash directory.t5813-proto-disable-ssh
Git's test scripts get quite a bit confused, as their assumptions have
been shattered. Not only does this path contain a colon (oh no!), it
also does not start with a slash.
This is a problem e.g. when constructing a URL as t5813 does it:
ssh://remote$PWD. Not only is it impossible to separate the "host" from
the path with a $PWD as above, even prefixing $PWD by a slash won't
work, as /C:/git-sdk-64/... is not a valid path.
As a workaround, detect when $PWD does not start with a slash on
Windows, and simply strip the drive prefix, using an obscure feature of
Windows paths: if an absolute Windows path starts with a slash, it is
implicitly prefixed by the drive prefix of the current directory. As we
are talking about the current directory here, anyway, that strategy
works.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
When t5605 tries to verify that files are hardlinked (or that they are
not), it uses the `-links` option of the `find` utility.
BusyBox' implementation does not support that option, and BusyBox-w32's
lstat() does not even report the number of hard links correctly (for
performance reasons).
So let's just switch to a different method that actually works on
Windows.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
While it may seem super convenient to some old Unix hands to simpy
require Perl to be available when running the test suite, this is a
major hassle on Windows, where we want to verify that Perl is not,
actually, required in a NO_PERL build.
As a super ugly workaround, we "install" a script into /usr/bin/perl
reading like this:
#!/bin/sh
# We'd much rather avoid requiring Perl altogether when testing
# an installed Git. Oh well, that's why we cannot have nice
# things.
exec c:/git-sdk-64/usr/bin/perl.exe "$@"
The problem with that is that BusyBox assumes that the #! line in a
script refers to an executable, not to a script. So when it encounters
the line #!/usr/bin/perl in t5532's proxy-get-cmd, it barfs.
Let's help this situation by simply executing the Perl script with the
"interpreter" specified explicitly.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
At some stage, t5003-archive-zip wants to add a file that is not ASCII.
To that end, it uses /bin/sh. But that file may actually not exist (it
is too easy to forget that not all the world is Unix/Linux...)! Besides,
we already have perfectly fine binary files intended for use solely by
the tests. So let's use one of them instead.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Since c6b0831c9c (docs: warn about possible '=' in clean/smudge filter
process values, 2016-12-03), t0021 writes out a file with quotes in its
name, and MSYS2's path conversion heuristics mistakes that to mean that
we are not talking about a path here.
Therefore, we need to use Windows paths, as the test-helper is a Win32
program that would otherwise have no idea where to look for the file.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
When running with BusyBox, we will want to avoid calling executables on
the PATH that are implemented in BusyBox itself.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The -W option is only understood by MSYS2 Bash's pwd command. We already
make sure to override `pwd` by `builtin pwd -W` for MINGW, so let's not
double the effort here.
This will also help when switching the shell to another one (such as
BusyBox' ash) whose pwd does *not* understand the -W option.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Traditionally, Git for Windows' SDK uses Bash as its default shell.
However, other Unix shells are available, too. Most notably, the Win32
port of BusyBox comes with `ash` whose `pwd` command already prints
Windows paths as Git for Windows wants them, while there is not even a
`builtin` command.
Therefore, let's be careful not to override `pwd` unless we know that
the `builtin` command is available.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
BusyBox-w32 is a true Win32 application, i.e. it does not come with a
POSIX emulation layer.
That also means that it does *not* use the Unix convention of separating
the entries in the PATH variable using colons, but semicolons.
However, there are also BusyBox ports to Windows which use a POSIX
emulation layer such as Cygwin's or MSYS2's runtime, i.e. using colons
as PATH separators.
As a tell-tale, let's use the presence of semicolons in the PATH
variable: on Unix, it is highly unlikely that it contains semicolons,
and on Windows (without POSIX emulation), it is virtually guaranteed, as
everybody should have both $SYSTEMROOT and $SYSTEMROOT/system32 in their
PATH.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The idea is to allow running the test suite on MinGit with BusyBox
installed in /mingw64/bin/sh.exe. In that case, we will want to exclude
sort & find (and other Unix utilities) from being bundled.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
We already have a directory where we store files intended for use by
multiple test scripts. The same directory is a better home for the
test-binary-*.png files than t/.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
It is convenient to assume that everybody who wants to build & test Git
has access to a working `iconv` executable (after all, we already pretty
much require libiconv).
However, that limits esoteric test scenarios such as Git for Windows',
where an end user installation has to ship with `iconv` for the sole
purpose of being testable. That payload serves no other purpose.
So let's just have a test helper (to be able to test Git, the test
helpers have to be available, after all) to act as `iconv` replacement.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This helper is slightly more performant than the script with MSYS2's
Bash. And a lot more readable.
To accommodate t1050, which wants to compare files weighing in with 3MB
(falling outside of t1050's malloc limit of 1.5MB), we simply lift the
allocation limit by setting the environment variable GIT_ALLOC_LIMIT to
zero when calling the helper.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
It is a bit strange, and even undesirable, to require Perl just to run
the test suite even when NO_PERL was set.
This patch does not fix this problem by any stretch of imagination.
However, it fixes *the* Perl invocation that *every single* test script
has to run.
While at it, it makes the source code also more grep'able, as the code
that unsets some, but not all, GIT_* environment variables just became a
*lot* more explicit. And all that while still reducing the total number
of lines.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
BusyBox comes with a ton of applets ("applet" being the identical
concept to Git's "builtins"). And similar to Git's builtins, the applets
can be called via `busybox <command>`, or the BusyBox executable can be
copied/hard-linked to the command name.
The similarities do not end here. Just as with Git's builtins, it is
problematic that BusyBox' hard-linked applets cannot easily be put into
a .zip file: .zip archives have no concept of hard-links and therefore
would store identical copies (and also extract identical copies,
"inflating" the archive unnecessarily).
To counteract that issue, MinGit already ships without hard-linked
copies of the builtins, and the plan is to do the same with BusyBox'
applets: simply ship busybox.exe as single executable, without
hard-linked applets.
To accommodate that, Git is being taught by this commit a very special
trick, exploiting the fact that it is possible to call an executable
with a command-line whose argv[0] is different from the executable's
name: when `sh` is to be spawned, and no `sh` is found in the PATH, but
busybox.exe is, use that executable (with unchanged argv).
Likewise, if any executable to be spawned is not on the PATH, but
busybox.exe is found, parse the output of `busybox.exe --help` to find
out what applets are included, and if the command matches an included
applet name, use busybox.exe to execute it.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
To verify that the symlink is resolved correctly, we use the fact that
`git.exe` is a native Win32 program, and that `git.exe config -f <path>`
therefore uses the native symlink resolution.
Signed-off-by: Bert Belder <bertbelder@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The main idea of this patch is that even if we have to look up the
absolute path of the script, if only the basename was specified as
argv[0], then we should use that basename on the command line, too, not
the absolute path.
This patch will also help with the upcoming patch where we automatically
substitute "sh ..." by "busybox sh ..." if "sh" is not in the PATH but
"busybox" is: we will do that by substituting the actual executable, but
still keep prepending "sh" to the command line.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
On Windows, symbolic links have a type: a "file symlink" must point at
a file, and a "directory symlink" must point at a directory. If the
type of symlink does not match its target, it doesn't work.
Git does not record the type of symlink in the index or in a tree. On
checkout it'll guess the type, which only works if the target exists
at the time the symlink is created. This may often not be the case,
for example when the link points at a directory inside a submodule.
By specifying `symlink=file` or `symlink=dir` the user can specify what
type of symlink Git should create, so Git doesn't have to rely on
unreliable heuristics.
Signed-off-by: Bert Belder <bertbelder@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
On Windows, symbolic links actually have a type depending on the target:
it can be a file or a directory.
In certain circumstances, this poses problems, e.g. when a symbolic link
is supposed to point into a submodule that is not checked out, so there
is no way for Git to auto-detect the type.
To help with that, we will add support over the course of the next
commits to specify that symlink type via the Git attributes. This
requires an index_state, though, something that Git for Windows'
`symlink()` replacement cannot know about because the function signature
is defined by the POSIX standard and not ours to change.
So let's introduce a helper function to create symbolic links that
*does* know about the index_state.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
... even if they may look like them.
As looking up the target of the "symbolic link" (just to see whether it
starts with `/ContainerMappedDirectories/`) is pretty expensive, we
do it when we can be *really* sure that there is a possibility that this
might be the case.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: JiSeop Moon <zcube@zcube.kr>
In preparation for making this function a bit more complicated (to allow
for special-casing the `ContainerMappedDirectories` in Windows
containers, which look like a symbolic link, but are not), let's move it
out of the header.
Signed-off-by: JiSeop Moon <zcube@zcube.kr>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
In https://github.com/git-for-windows/git/pull/2637, we fixed a bug
where symbolic links' target path sizes were recorded incorrectly in the
index. The downside of this fix was that every user with tracked
symbolic links in their checkouts would see them as modified in `git
status`, but not in `git diff`, and only a `git add <path>` (or `git add
-u`) would "fix" this.
Let's do better than that: we can detect that situation and simply
pretend that a symbolic link with a known bad size (or a size that just
happens to be that bad size, a _very_ unlikely scenario because it would
overflow our buffers due to the trailing NUL byte) means that it needs
to be re-checked as if we had just checked it out.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
It is a known issue that a rename() can fail with an "Access denied"
error at times, when copying followed by deleting the original file
works. Let's just fall back to that behavior.
Signed-off-by: JiSeop Moon <zcube@zcube.kr>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
When creating directories via `safe_create_leading_directories()`, we
might encounter an already-existing directory which is not
readable by the current user. To handle that situation, Git's code calls
`stat()` to determine whether we're looking at a directory.
In such a case, `CreateFile()` will fail, though, no matter what, and
consequently `mingw_stat()` will fail, too. But POSIX semantics seem to
still allow `stat()` to go forward.
So let's call `mingw_lstat()` for the rescue if we fail to get a file
handle due to denied permission in `mingw_stat()`, and fill the stat
info that way.
We need to be careful to not allow this to go forward in case that we're
looking at a symbolic link: to resolve the link, we would still have to
create a file handle, and we just found out that we cannot. Therefore,
`stat()` still needs to fail with `EACCES` in that case.
This fixes https://github.com/git-for-windows/git/issues/2531.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
With Windows 10 Build 14972 in Developer Mode, a new flag is supported
by CreateSymbolicLink() to create symbolic links even when running
outside of an elevated session (which was previously required).
This new flag is called SYMBOLIC_LINK_FLAG_ALLOW_UNPRIVILEGED_CREATE and
has the numeric value 0x02.
Previous Windows 10 versions will not understand that flag and return an
ERROR_INVALID_PARAMETER, therefore we have to be careful to try passing
that flag only when the build number indicates that it is supported.
For more information about the new flag, see this blog post:
https://blogs.windows.com/buildingapps/2016/12/02/symlinks-windows-10/
This patch is loosely based on the patch submitted by Samuel D. Leslie
as https://github.com/git-for-windows/git/pull/1184.
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>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.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>
This commit fixes mingw_lstat by computing the proper size for symlinks
according to POSIX. POSIX specifies that upon successful return from
lstat: "the value of the st_size member shall be set to the length of
the pathname contained in the symbolic link not including any
terminating null byte".
Prior to this commit the mingw_lstat function returned a fixed size of
4096. This caused problems in git repositories that were accessed by
git for Cygwin or git for WSL. For example, doing `git reset --hard`
using git for Windows would update the size of symlinks in the index
to be 4096; at a later time git for Cygwin or git for WSL would find
that symlinks have changed size during `git status`. Vice versa doing
`git reset --hard` in git for Cygwin or git for WSL would update the
size of symlinks in the index with the correct value, only for git for
Windows to find incorrectly at a later time that the size had changed.
Signed-off-by: Bill Zissimopoulos <billziss@navimatics.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.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.
Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.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>
