Checking the work tree status is quite slow on Windows, due to slow lstat
emulation (git calls lstat once for each file in the index). Windows
operating system APIs seem to be much better at scanning the status
of entire directories than checking single files.
Add an lstat implementation that uses a cache for lstat data. Cache misses
read the entire parent directory and add it to the cache. Subsequent lstat
calls for the same directory are served directly from the cache.
Also implement opendir / readdir / closedir so that they create and use
directory listings in the cache.
The cache doesn't track file system changes and doesn't plug into any
modifying file APIs, so it has to be explicitly enabled for git functions
that don't modify the working copy.
Note: in an earlier version of this patch, the cache was always active and
tracked file system changes via ReadDirectoryChangesW. However, this was
much more complex and had negative impact on the performance of modifying
git commands such as 'git checkout'.
Signed-off-by: Karsten Blees <blees@dcon.de>
Add a macro to mark code sections that only read from the file system,
along with a config option and documentation.
This facilitates implementation of relatively simple file system level
caches without the need to synchronize with the file system.
Enable read-only sections for 'git status' and preload_index.
Signed-off-by: Karsten Blees <blees@dcon.de>
Emulating the POSIX lstat API on Windows via GetFileAttributes[Ex] is quite
slow. Windows operating system APIs seem to be much better at scanning the
status of entire directories than checking single files. A caching
implementation may improve performance by bulk-reading entire directories
or reusing data obtained via opendir / readdir.
Make the lstat implementation pluggable so that it can be switched at
runtime, e.g. based on a config option.
Signed-off-by: Karsten Blees <blees@dcon.de>
Emulating the POSIX dirent API on Windows via FindFirstFile/FindNextFile is
pretty staightforward, however, most of the information provided in the
WIN32_FIND_DATA structure is thrown away in the process. A more
sophisticated implementation may cache this data, e.g. for later reuse in
calls to lstat.
Make the dirent implementation pluggable so that it can be switched at
runtime, e.g. based on a config option.
Define a base DIR structure with pointers to readdir/closedir that match
the opendir implementation (i.e. similar to vtable pointers in OOP).
Define readdir/closedir so that they call the function pointers in the DIR
structure. This allows to choose the opendir implementation on a
call-by-call basis.
Move the fixed sized dirent.d_name buffer to the dirent-specific DIR
structure, as d_name may be implementation specific (e.g. a caching
implementation may just set d_name to point into the cache instead of
copying the entire file name string).
Signed-off-by: Karsten Blees <blees@dcon.de>
Git for Windows ships with its own Perl interpreter, and insists on
using it, so it will most likely wreak havoc if PERL5LIB is set before
launching Git.
Let's just unset that environment variables when spawning processes.
To make this feature extensible (and overrideable), there is a new
config setting `core.unsetenvvars` that allows specifying a
comma-separated list of names to unset before spawning processes.
Reported by Gabriel Fuhrmann.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
In the Git for Windows project, we have ample precendent for config
settings that apply to Windows, and to Windows only.
Let's formalize this concept by introducing a platform_core_config()
function that can be #define'd in a platform-specific manner.
This will allow us to contain platform-specific code better, as the
corresponding variables no longer need to be exported so that they can
be defined in environment.c and be set in config.c
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This is the convention elsewhere (and prepares for the case where we may
need to pass callback data).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
A possible oom error is now caught as a fatal error, instead of
continuing and dereferencing NULL.
* ao/path-use-xmalloc:
path.c: use xmalloc() in add_to_trie()
It was observed that the current implementation of of get_proc_addr()
fails to load the kernel32.dll with code ERROR_INVALID_PARAMETER.
Probably the reason is that kernel32.dll is already loaded. The
behavior was seen at Windows SP1, both 32bit and 64bit. Probably it
would behave same way in some or all other Windows versions.
This breaks all usages of "clone --local", including the automatic
tests where they call it.
The function CreateHardLink is available in all supported Windows
versions (since Windows XP), so there is no more need to resolve it
in runtime.
Signed-off-by: Max Kirillov <max@max630.net>
The descriptions of the options '--parents', '--children' and
'--graph' say "see 'History Simplification' below", although the
referred section is in fact above the description of these options.
Send readers in the right direction by saying "above" instead of
"below".
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Transactions to update multiple references that involves a deletion
was quite broken in an error codepath and did not abort everything
correctly.
* mh/ref-locking-fix:
files_transaction_prepare(): fix handling of ref lock failure
t1404: add a bunch of tests of D/F conflicts
Add usage of xmalloc() instead of malloc() in add_to_trie() as xmalloc wraps
and checks memory allocation result.
Signed-off-by: Andrey Okoshkin <a.okoshkin@samsung.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since dc39e09942 (files_ref_store: use a transaction to update packed
refs, 2017-09-08), failure to lock a reference has been handled
incorrectly by `files_transaction_prepare()`. If
`lock_ref_for_update()` fails in the lock-acquisition loop of that
function, it sets `ret` then breaks out of that loop. Prior to
dc39e09942, that was OK, because the only thing following the loop was
the cleanup code. But dc39e09942 added another blurb of code between
the loop and the cleanup. That blurb sometimes resets `ret` to zero,
making the cleanup code think that the locking was successful.
Specifically, whenever
* One or more reference deletions have been processed successfully in
the lock-acquisition loop. (Processing the first such reference
causes a packed-ref transaction to be initialized.)
* Then `lock_ref_for_update()` fails for a subsequent reference. Such
a failure can happen for a number of reasons, such as the old SHA-1
not being correct, lock contention, etc. This causes a `break` out
of the lock-acquisition loop.
* The `packed-refs` lock is acquired successfully and
`ref_transaction_prepare()` succeeds for the packed-ref transaction.
This has the effect of resetting `ret` back to 0, and making the
cleanup code think that lock acquisition was successful.
In that case, any reference updates that were processed prior to
breaking out of the loop would be carried out (loose and packed), but
the reference that couldn't be locked and any subsequent references
would silently be ignored.
This can easily cause data loss if, for example, the user was trying
to push a new name for an existing branch while deleting the old name.
After the push, the branch could be left unreachable, and could even
subsequently be garbage-collected.
This problem was noticed in the context of deleting one reference and
creating another in a single transaction, when the two references D/F
conflict with each other, like
git update-ref --stdin <<EOF
delete refs/foo
create refs/foo/bar HEAD
EOF
This triggers the above bug because the deletion is processed
successfully for `refs/foo`, then the D/F conflict causes
`lock_ref_for_update()` to fail when `refs/foo/bar` is processed. In
this case the transaction *should* fail, but instead it causes
`refs/foo` to be deleted without creating `refs/foo`. This could
easily result in data loss.
The fix is simple: instead of just breaking out of the loop, jump
directly to the cleanup code. This fixes some tests in t1404 that were
added in the previous commit.
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It is currently not allowed, in a single transaction, to add one
reference and delete another reference if the two reference names D/F
conflict with each other (e.g., like `refs/foo/bar` and `refs/foo`).
The reason is that the code would need to take locks
$GIT_DIR/refs/foo.lock
$GIT_DIR/refs/foo/bar.lock
But the latter lock couldn't coexist with the loose reference file
$GIT_DIR/refs/foo
, because `$GIT_DIR/refs/foo` cannot be both a directory and a file at
the same time (hence the name "D/F conflict).
Add a bunch of tests that we cleanly reject such transactions.
In fact, many of the new tests currently fail. They will be fixed in
the next commit along with an explanation.
Reported-by: Jeff King <peff@peff.net>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A very common assumption in Git's source code base is that
offset_1st_component() returns either 0 for relative paths, or 1 for
absolute paths that start with a slash. In other words, the return value
is either 0 or points just after the dir separator.
This assumption is not fulfilled when calling offset_1st_component()
e.g. on UNC paths on Windows, e.g. "//my-server/my-share". In this case,
offset_1st_component() returns the length of the entire string (which is
correct, because stripping the last "component" would not result in a
valid directory), yet the return value still does not point just after a
dir separator.
This assumption is most prominently seen in the
setup_git_directory_gently_1() function, where we want to append a
".git" component and simply assume that there is already a dir
separator. In the UNC example given above, this assumption is incorrect.
As a consequence, Git will fail to handle a worktree at the top of a UNC
share correctly.
Let's fix this by adding a dir separator specifically for that case: we
found that there is no first component in the path and it does not end
in a dir separator? Then add it.
This fixes https://github.com/git-for-windows/git/issues/1320
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This reflects v2 of the ref-filter-remote-name branch, submitted as:
https://public-inbox.org/git/cover.1507205895.git.johannes.schindelin@gmx.de
The only addition is a fourth patch that marks all of this shebang as
experimental, subject to design changes without prior warning.
By exposing this as an experimental feature to users, hopefully this
patch series will mature quicker (not so much in the "beautiful code"
sense, but more in the "does it work in practice" sense).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
These expansions will most likely be introduced into Git for Windows as
a test balloon first, and if they work out as expected, we'll try to get
the patches into upstream Git.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This not only prevents regressions, but also serves as documentation
what this new feature is expected to do.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
There are times when scripts want to know not only the name of the
push branch on the remote, but also the name of the branch as known
by the remote repository.
An example of this is when a tool wants to push to the very same branch
from which it would pull automatically, i.e. the `<remote>` and the `<to>`
in `git push <remote> <from>:<to>` would be provided by
`%(upstream:remotename)` and `%(upstream:remoteref)`, respectively.
This patch offers the new suffix :remoteref for the `upstream` and `push`
atoms, allowing to show exactly that. Example:
$ cat .git/config
...
[remote "origin"]
url = https://where.do.we.come/from
fetch = refs/heads/*:refs/remote/origin/*
[branch "master"]
remote = origin
merge = refs/heads/master
[branch "develop/with/topics"]
remote = origin
merge = refs/heads/develop/with/topics
...
$ git for-each-ref \
--format='%(push) %(push:remoteref)' \
refs/heads
refs/remotes/origin/master refs/heads/master
refs/remotes/origin/develop/with/topics refs/heads/develop/with/topics
Signed-off-by: J Wyman <jwyman@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
There are times when e.g. scripts want to know not only the name of the
upstream branch on the remote repository, but also the name of the
remote.
This patch offers the new suffix :remotename for the upstream and for
the push atoms, allowing to show exactly that. Example:
$ cat .git/config
...
[remote "origin"]
url = https://where.do.we.come/from
fetch = refs/heads/*:refs/remote/origin/*
[remote "hello-world"]
url = https://hello.world/git
fetch = refs/heads/*:refs/remote/origin/*
pushURL = hello.world:git
push = refs/heads/*:refs/heads/*
[branch "master"]
remote = origin
pushRemote = hello-world
...
$ git for-each-ref \
--format='%(upstream) %(upstream:remotename) \
%(push:remotename)' refs/heads/master
refs/remotes/origin/master origin hello-world
The implementation chooses *not* to DWIM the push remote if no explicit
push remote was configured; The reason is that it is possible to DWIM this
by using
%(if)%(push:remotename)%(then)
%(push:remotename)
%(else)
%(upstream:remotename)
%(end)
while it would be impossible to "un-DWIM" the information in case the
caller is really only interested in explicit push remotes.
While `:remote` would be shorter, it would also be a bit more ambiguous,
and it would also shut the door e.g. for `:remoteref` (which would
obviously refer to the corresponding ref in the remote repository).
Note: the dashless, non-CamelCased form `:remotename` follows the
example of the `:trackshort` example.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
When running an external diff from, say, a diff tool, it is safe to
assume that we want to write the files in question. On Windows, that
means that there cannot be any other process holding an open handle to
said files.
So let's make sure that `git diff` itself is not holding any open handle
to the files in question.
This fixes https://github.com/git-for-windows/git/issues/1315
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
We have this loop where we try to remove the read-only attribute when
rename() fails and try again. If it fails again, let's not try to remove
the read-only attribute and try *again*.
This fixes https://github.com/git-for-windows/git/issues/1299
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
These changes are necessary to support better Git for Windows' new
auto-update feature.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
"Question?" is maybe not the most informative thing to ask. In the
absence of better information, it is the best we can do, of course.
However, Git for Windows' auto updater just learned the trick to use
git-gui--askyesno to ask the user whether to update now or not. And in
this scripted scenario, we can easily pass a command-line option to
change the window title.
So let's support that with the new `--title <title>` option.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The text wrapping seems to be aligned to the right side of the Yes
button, leaving an awful lot of empty space.
Let's try to counter this by using pixel units.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Add .LIBs for zlib and openssl to <AdditionalDependencies>
to help linker when building with VS2017.
This closes https://github.com/git-for-windows/git/issues/1234
Note: this patch still leaves a couple of TODOs:
- It should be possible to add GEN.DEPS\lib to
<AdditionalLibraryDependencies> and then just set
<AdditionalDependencies> to the library basenames.
- Likewise, you should be able to copy GEN.DEPS\bin\*.dll
to the destination directory rather than using the full
paths in the $afterTargets lines.
(This is in line with items in <AdditionalIncludeDirectories>
referencing GEN.DEPS\include.)
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
From the documentation of said setting:
This boolean will enable fsync() when writing object files.
This is a total waste of time and effort on a filesystem that
orders data writes properly, but can be useful for filesystems
that do not use journalling (traditional UNIX filesystems) or
that only journal metadata and not file contents (OS X’s HFS+,
or Linux ext3 with "data=writeback").
The most common file system on Windows (NTFS) does not guarantee that
order, therefore a sudden loss of power (or any other event causing an
unclean shutdown) would cause corrupt files (i.e. files filled with
NULs). Therefore we need to change the default.
Note that the documentation makes it sound as if this causes really bad
performance. In reality, writing loose objects is something that is done
only rarely, and only a handful of files at a time.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Toolset v120 corresponds to Visual Studio 2013. We already used
dependencies that were hardcoded to v140 (i.e. Visual Studio 2015), so
let's just remove the cruft.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
