Commit Graph

91791 Commits

Author SHA1 Message Date
Karsten Blees
ba90de8979 Win32: mingw_unlink: support symlinks to directories
_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>
2018-11-20 11:23:07 +01:00
Karsten Blees
809c4e1621 Win32: add symlink-specific error codes
Signed-off-by: Karsten Blees <blees@dcon.de>
2018-11-20 11:23:06 +01:00
Karsten Blees
cc13e1436a Win32: change default of 'core.symlinks' to false
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>
2018-11-20 11:23:06 +01:00
Karsten Blees
49800df416 Win32: factor out retry logic
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>
2018-11-20 11:23:06 +01:00
Karsten Blees
d7e5e85296 Win32: lstat(): return adequate stat.st_size for symlinks
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>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2018-11-20 11:23:06 +01:00
Karsten Blees
1009fcc239 Win32: teach fscache and dirent about symlinks
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>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2018-11-20 11:23:06 +01:00
Karsten Blees
ad19d10371 Win32: let mingw_lstat() error early upon problems with reparse points
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>
2018-11-20 11:23:05 +01:00
Karsten Blees
a8a419c6e5 Win32: remove separate do_lstat() function
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>
2018-11-20 11:23:05 +01:00
Karsten Blees
349750a7c6 Win32: implement stat() with symlink support
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>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2018-11-20 11:23:05 +01:00
Karsten Blees
e2c1632ad3 Win32: don't call GetFileAttributes twice in mingw_lstat()
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>
2018-11-20 11:23:05 +01:00
Karsten Blees
cd73822bbe lockfile.c: use is_dir_sep() instead of hardcoded '/' checks
Signed-off-by: Karsten Blees <blees@dcon.de>
2018-11-20 11:23:05 +01:00
Karsten Blees
452ced7756 strbuf_readlink: support link targets that exceed PATH_MAX
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>
2018-11-20 11:23:05 +01:00
Karsten Blees
626fd82747 strbuf_readlink: don't call readlink twice if hint is the exact link size
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>
2018-11-20 11:23:04 +01:00
Johannes Schindelin
1bf44a19df Merge branch 'maybe-drop'
These patches are probably no longer necessary. Make sure before
dropping them, though.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2018-11-20 11:23:04 +01:00
Johannes Schindelin
a9a6a15754 t9001: work around hard-to-debug hangs
Just like the workaround we added for t9116, t9001.83 hangs sometimes --
but not always! -- when being run in the Git for Windows SDK.

The issue seems to be related to redirection via a pipe, but it is really
hard to diagnose, what with git.exe (a non-MSYS2 program) calling a Perl
script (which is executed by an MSYS2 Perl), piping into another MSYS2
program.

As hunting time is scarce these days, simply work around this for now and
leave the real diagnosis and resolution for later.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2018-11-20 11:23:04 +01:00
Johannes Schindelin
699a244f66 diff: munmap() file contents before running external diff
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>
2018-11-20 11:23:03 +01:00
Johannes Schindelin
6bc2038f66 t9116: work around hard-to-debug hangs
As of a couple of weeks ago, t9116 hangs sometimes -- but not always! --
when being run in the Git for Windows SDK.

The issue seems to be related to redirection via a pipe, but it is really
hard to diagnose, what with git.exe (a non-MSYS2 program) calling a Perl
script (which is executed by an MSYS2 Perl), piping into another MSYS2
program.

As hunting time is scarce these days, simply work around this for now and
leave the real diagnosis and resolution for later.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2018-11-20 11:23:03 +01:00
Johannes Schindelin
08dc75b1c3 mingw: make is_hidden tests in t0001/t5611 more robust
We should not actually expect the first `attrib.exe` in the PATH to
be the one we are looking for. Or that it is in the PATH, for that
matter.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2018-11-20 11:23:03 +01:00
Johannes Schindelin
e883a1bdf0 Skip t9020 with MSys2
POSIX-to-Windows path mangling would make it fail.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2018-11-20 11:23:03 +01:00
Johannes Schindelin
f091a57699 Tests: optionally skip redirecting stdin/stdout/stderr
There is a really useful debugging technique developed by Sverre
Rabbelier that inserts "bash &&" somewhere in the test scripts, letting
the developer interact at given points with the current state.

Another debugging technique, used a lot by this here coder, is to run
certain executables via gdb by guarding a "gdb -args" call in
bin-wrappers/git.

Both techniques were disabled by 781f76b1(test-lib: redirect stdin of
tests).

Let's reinstate the ability to run an interactive shell by making the
redirection optional: setting the TEST_NO_REDIRECT environment variable
will skip the redirection.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2018-11-20 11:23:03 +01:00
Sebastian Schuberth
3a9a005124 MinGW: Use MakeMaker to build the Perl libraries
This way the libraries get properly installed into the "site_perl"
directory and we just have to move them out of the "mingw" directory.

Signed-off-by: Sebastian Schuberth <sschuberth@gmail.com>
2018-11-20 11:23:03 +01:00
Johannes Schindelin
7e3c5ecfe5 mingw: ensure valid CTYPE
A change between versions 2.4.1 and 2.6.0 of the MSYS2 runtime modified
how Cygwin's runtime (and hence Git for Windows' MSYS2 runtime
derivative) handles locales: d16a56306d (Consolidate wctomb/mbtowc calls
for POSIX-1.2008, 2016-07-20).

An unintended side-effect is that "cold-calling" into the POSIX
emulation will start with a locale based on the current code page,
something that Git for Windows is very ill-prepared for, as it expects
to be able to pass a command-line containing non-ASCII characters to the
shell without having those characters munged.

One symptom of this behavior: when `git clone` or `git fetch` shell out
to call `git-upload-pack` with a path that contains non-ASCII
characters, the shell tried to interpret the entire command-line
(including command-line parameters) as executable path, which obviously
must fail.

This fixes https://github.com/git-for-windows/git/issues/1036

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2018-11-20 11:23:02 +01:00
Johannes Schindelin
ed6d834a19 Unbreak interactive GPG prompt upon signing
With the recent update in efee955 (gpg-interface: check gpg signature
creation status, 2016-06-17), we ask GPG to send all status updates to
stderr, and then catch the stderr in an strbuf.

But GPG might fail, and send error messages to stderr. And we simply
do not show them to the user.

Even worse: this swallows any interactive prompt for a passphrase. And
detaches stderr from the tty so that the passphrase cannot be read.

So while the first problem could be fixed (by printing the captured
stderr upon error), the second problem cannot be easily fixed, and
presents a major regression.

So let's just revert commit efee9553a4.

This fixes https://github.com/git-for-windows/git/issues/871

Cc: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2018-11-20 11:23:02 +01:00
Johannes Schindelin
95ac0bab17 winansi: simplify loading the GetCurrentConsoleFontEx() function
We introduced helper macros to simplify loading functions dynamically.
Might just as well use them.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2018-11-20 11:23:02 +01:00
Karsten Blees
746ede25ef compat/terminal.c: only use the Windows console if bash 'read -r' fails
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>
2018-11-20 11:23:02 +01:00
Karsten Blees
8628eab7e6 mingw: Support git_terminal_prompt with more terminals
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>
2018-11-20 11:23:02 +01:00
nalla
521ae727f4 mingw: explicitly fflush stdout
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>
2018-11-20 11:23:02 +01:00
Karsten Blees
16e2f6e454 mingw: initialize HOME on startup
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>
2018-11-20 11:23:02 +01:00
Karsten Blees
12c3072574 gettext: always use UTF-8 on native Windows
Git on native Windows exclusively uses UTF-8 for console output (both with
mintty and native console windows). Gettext uses setlocale() to determine
the output encoding for translated text, however, MSVCRT's setlocale()
doesn't support UTF-8. As a result, translated text is encoded in system
encoding (GetAPC()), and non-ASCII chars are mangled in console output.

Use gettext's bind_textdomain_codeset() to force the encoding to UTF-8 on
native Windows.

In this developers' setup, HAVE_LIBCHARSET_H is apparently defined, but
we *really* want to override the locale_charset() here.

Signed-off-by: Karsten Blees <blees@dcon.de>
2018-11-20 11:23:01 +01:00
Johannes Schindelin
a11b4991d9 Avoid illegal filenames when building Documentation on NTFS
A '+' is not a valid part of a filename with Windows file systems (it is
reserved because the '+' operator meant file concatenation back in the
DOS days).

Let's just not use it.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2018-11-20 11:23:01 +01:00
Johannes Schindelin
eb489dcf95 mingw: enable stack smashing protector
As suggested privately to Brendan Forster by some unnamed person
(suggestion for the future: use the public mailing list, or even the
public GitHub issue tracker, that is a much better place to offer such
suggestions), we should make use of gcc's stack smashing protector that
helps detect stack buffer overruns early.

Rather than using -fstack-protector, we use -fstack-protector-strong
because it strikes a better balance between how much code is affected
and the performance impact.

In a local test (time git log --grep=is -p), best of 5 timings went from
23.009s to 22.997s (i.e. the performance impact was *well* lost in the
noise).

This fixes https://github.com/git-for-windows/git/issues/501

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2018-11-20 11:23:01 +01:00
Cesar Eduardo Barros
3d35d0c9e7 mingw: Embed a manifest to trick UAC into Doing The Right Thing
On Windows >= Vista, not having an application manifest with a
requestedExecutionLevel can cause several kinds of confusing behavior.

The first and more obvious behavior is "Installer Detection", where
Windows sometimes decides (by looking at things like the file name and
even sequences of bytes within the executable) that an executable is an
installer and should run elevated (causing the well-known popup dialog
to appear). In Git's context, subcommands such as "git patch-id" or "git
update-index" fall prey to this behavior.

The second and more confusing behavior is "File Virtualization". It
means that when files are written without having write permission, it
does not fail (as expected), but they are instead redirected to
somewhere else. When the files are read, the original contents are
returned, though, not the ones that were just written somewhere else.
Even more confusing, not all write accesses are redirected; Trying to
write to write-protected .exe files, for example, will fail instead of
redirecting.

In addition to being unwanted behavior, File Virtualization causes
dramatic slowdowns in Git (see for instance
http://code.google.com/p/msysgit/issues/detail?id=320).

There are two ways to prevent those two behaviors: Either you embed an
application manifest within all your executables, or you add an external
manifest (a file with the same name followed by .manifest) to all your
executables. Since Git's builtins are hardlinked (or copied), it is
simpler and more robust to embed a manifest.

A recent enough MSVC compiler should already embed a working internal
manifest, but for MinGW you have to do so by hand.

Very lightly tested on Wine, where like on Windows XP it should not make
any difference.

References:
  - New UAC Technologies for Windows Vista
    http://msdn.microsoft.com/en-us/library/bb756960.aspx
  - Create and Embed an Application Manifest (UAC)
    http://msdn.microsoft.com/en-us/library/bb756929.aspx

[js: simplified the embedding dramatically by reusing Git for Windows'
existing Windows resource file, removed the optional (and dubious)
processorArchitecture attribute of the manifest's assemblyIdentity
section.]

Signed-off-by: Cesar Eduardo Barros <cesarb@cesarb.net>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2018-11-20 11:23:01 +01:00
Johannes Schindelin
11d5be18b1 Build Python stuff with MSys2
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2018-11-20 11:23:01 +01:00
Johannes Schindelin
3b852c5a9d Help debugging with MSys2 by optionally executing bash with strace
MSys2's strace facility is very useful for debugging... With this patch,
the bash will be executed through strace if the environment variable
GIT_STRACE_COMMANDS is set, which comes in real handy when investigating
issues in the test suite.

Also support passing a path to a log file via GIT_STRACE_COMMANDS to
force Git to call strace.exe with the `-o <path>` argument, i.e. to log
into a file rather than print the log directly.

That comes in handy when the output would otherwise misinterpreted by a
calling process as part of Git's output.

Note: the values "1", "yes" or "true" are *not* specifying paths, but
tell Git to let strace.exe log directly to the console.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2018-11-20 11:23:00 +01:00
Sebastian Schuberth
ebe9fca10c Makefile: Set htmldir to match the default HTML docs location under MSYS
Signed-off-by: Sebastian Schuberth <sschuberth@gmail.com>
2018-11-20 11:23:00 +01:00
Karsten Blees
df160831af Win32: fix 'lstat("dir/")' with long paths
Use a suffciently large buffer to strip the trailing slash.

Signed-off-by: Karsten Blees <blees@dcon.de>
2018-11-20 11:23:00 +01:00
Karsten Blees
434dfeeaad Win32: support long paths
Windows paths are typically limited to MAX_PATH = 260 characters, even
though the underlying NTFS file system supports paths up to 32,767 chars.
This limitation is also evident in Windows Explorer, cmd.exe and many
other applications (including IDEs).

Particularly annoying is that most Windows APIs return bogus error codes
if a relative path only barely exceeds MAX_PATH in conjunction with the
current directory, e.g. ERROR_PATH_NOT_FOUND / ENOENT instead of the
infinitely more helpful ERROR_FILENAME_EXCED_RANGE / ENAMETOOLONG.

Many Windows wide char APIs support longer than MAX_PATH paths through the
file namespace prefix ('\\?\' or '\\?\UNC\') followed by an absolute path.
Notable exceptions include functions dealing with executables and the
current directory (CreateProcess, LoadLibrary, Get/SetCurrentDirectory) as
well as the entire shell API (ShellExecute, SHGetSpecialFolderPath...).

Introduce a handle_long_path function to check the length of a specified
path properly (and fail with ENAMETOOLONG), and to optionally expand long
paths using the '\\?\' file namespace prefix. Short paths will not be
modified, so we don't need to worry about device names (NUL, CON, AUX).

Contrary to MSDN docs, the GetFullPathNameW function doesn't seem to be
limited to MAX_PATH (at least not on Win7), so we can use it to do the
heavy lifting of the conversion (translate '/' to '\', eliminate '.' and
'..', and make an absolute path).

Add long path error checking to xutftowcs_path for APIs with hard MAX_PATH
limit.

Add a new MAX_LONG_PATH constant and xutftowcs_long_path function for APIs
that support long paths.

While improved error checking is always active, long paths support must be
explicitly enabled via 'core.longpaths' option. This is to prevent end
users to shoot themselves in the foot by checking out files that Windows
Explorer, cmd/bash or their favorite IDE cannot handle.

Test suite:
Test the case is when the full pathname length of a dir is close
to 260 (MAX_PATH).
Bug report and an original reproducer by Andrey Rogozhnikov:
https://github.com/msysgit/git/pull/122#issuecomment-43604199

[jes: adjusted test number to avoid conflicts, added support for
chdir(), etc]

Thanks-to: Martin W. Kirst <maki@bitkings.de>
Thanks-to: Doug Kelly <dougk.ff7@gmail.com>
Signed-off-by: Karsten Blees <blees@dcon.de>
Original-test-by: Andrey Rogozhnikov <rogozhnikov.andrey@gmail.com>
Signed-off-by: Stepan Kasal <kasal@ucw.cz>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2018-11-20 11:23:00 +01:00
Doug Kelly
68741ffab4 pack-objects (mingw): demonstrate a segmentation fault with large deltas
There is a problem in the way 9ac3f0e5b3 (pack-objects: fix
performance issues on packing large deltas, 2018-07-22) initializes that
mutex in the `packing_data` struct. The problem manifests in a
segmentation fault on Windows, when a mutex (AKA critical section) is
accessed without being initialized. (With pthreads, you apparently do
not really have to initialize them?)

This was reported in https://github.com/git-for-windows/git/issues/1839.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2018-11-20 11:23:00 +01:00
Karsten Blees
7e9c269734 fscache: load directories only once
If multiple threads access a directory that is not yet in the cache, the
directory will be loaded by each thread. Only one of the results is added
to the cache, all others are leaked. This wastes performance and memory.

On cache miss, add a future object to the cache to indicate that the
directory is currently being loaded. Subsequent threads register themselves
with the future object and wait. When the first thread has loaded the
directory, it replaces the future object with the result and notifies
waiting threads.

Signed-off-by: Karsten Blees <blees@dcon.de>
2018-11-20 11:22:59 +01:00
Karsten Blees
40a4bbcde3 Win32: add a cache below mingw's lstat and dirent implementations
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>
2018-11-20 11:22:59 +01:00
Karsten Blees
37bb3c02b7 add infrastructure for read-only file system level caches
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>
2018-11-20 11:22:59 +01:00
Karsten Blees
013350e53e Win32: make the lstat implementation pluggable
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>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2018-11-20 11:22:59 +01:00
Karsten Blees
0f58449429 Win32: Make the dirent implementation pluggable
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>
2018-11-20 11:22:58 +01:00
Karsten Blees
880317adc5 Win32: dirent.c: Move opendir down
Move opendir down in preparation for the next patch.

Signed-off-by: Karsten Blees <blees@dcon.de>
2018-11-20 11:22:58 +01:00
Karsten Blees
4d646f0880 Win32: make FILETIME conversion functions public
We will use them in the upcoming "FSCache" patches (to accelerate
sequential lstat() calls).

Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2018-11-20 11:22:58 +01:00
Jeff Hostetler
581eb54410 Merge branch 'visual-studio'
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2018-11-20 11:22:58 +01:00
Jeff Hostetler
e9e7bd2a24 Merge branch 'msvc'
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2018-11-20 11:22:58 +01:00
Johannes Schindelin
02199ab058 git: avoid calling aliased builtins via their dashed form
This is one of the few places where Git violates its own deprecation of
the dashed form. It is not necessary, either.

As of 595d59e2b5 (git.c: ignore pager.* when launching builtin as
dashed external, 2017-08-02), Git wants to ignore the pager.* config
setting when expanding aliases. So let's strip out the
check_pager_config(<command-name>) call from the copy-edited code.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2018-11-20 11:22:57 +01:00
Johannes Schindelin
dec73368af t5505,t5516: create .git/branches/ when needed
It is a real old anachronism from the Cogito days to have a
.git/branches/ directory. And to have tests that ensure that Cogito
users can migrate away from using that directory.

But so be it, let's continue testing it.

Let's make sure, however, that git init does not need to create that
directory.

This bug was noticed when testing with templates that had been
pre-committed, skipping the empty branches/ directory of course because
Git does not track empty directories.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2018-11-20 11:22:57 +01:00
Johannes Schindelin
73f678259a bin-wrappers: append .exe to target paths if necessary
When compiling with Visual Studio, the projects' names are identical to
the executables modulo the extensions. Read: there will exist both a
directory called `git` as well as an executable called `git.exe` in the
end. Which means that the bin-wrappers *need* to target the `.exe` files
lest they try to execute directories.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2018-11-20 11:22:57 +01:00