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>
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>
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>
A long time ago, we decided to convert the entire environment to UTF-8
upon startup, and only work on a copy. This was responsible for several
serious bugs, because 3rd-party libraries (such as curl) are free to
work on the environment, too, and they had no idea about *our*
environment, and segmentation faults were the consequence.
In the meantime, Git consolidated a lot of `getenv()` calls (because it
is not really safe to hold onto the returned pointers for too long, and
also it is better to keep a copy and have a consistent state throughout
the lifetime of the process).
So the main reason for that wholesale conversion (performance) is
probably no longer valid.
As a matter of fact, for the MSVC-specific startup code, we could not
even make that startup conversion work because we have no longer access
to that (private) pointer to the environment of the MSVC runtime.
The plan, of course, is to consolidate those two divergent code paths by
using the newer, safer environment handling (which converts on the fly
with every getenv()/setenv() call).
There are already preliminary patches to that end in the
'unify-gcc-msvc-env-handling' branch on dscho/git, but we need to make
sure that this *really* does not regress performance, probably by adding
some code that accumulates stats (how often/how many nanoseconds spent),
and writes the numbers out in an atexit() handler, then run the test
suite and compare numbers.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.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>
The environment is modified in most surprising circumstances, and not
all of them are under Git's control. For example, calling
curl_global_init() on Windows will ensure that the CHARSET variable is
set, adding one if necessary.
While the previous commit worked around crashes triggered by such
outside changes of the environment by relaxing the requirement that the
environment be terminated by a NULL pointer, the other assumption made
by `mingw_getenv()` and `mingw_putenv()` is that the environment is
sorted, for efficient lookup via binary search.
Let's make real sure that our environment is intact before querying or
modifying it, and reinitialize our idea of the environment if necessary.
With this commit, before working on the environment we look briefly for
indicators that the environment was modified outside of our control, and
to ensure that it is terminated with a NULL pointer and sorted again in
that case.
Note: the indicators are maybe not sufficient. For example, when a
variable is removed, it will not be noticed. It might also be a problem
if outside changes to the environment result in a modified `environ`
pointer: it is unclear whether such a modification could result in a
problem when `mingw_putenv()` needs to `realloc()` the environment
buffer.
For the moment, however, the current fix works well enough, so let's
only face the potential problems when (and if!) they occur.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Outside of our Windows-specific code, the end of the environment can be
marked also by a pointer to a NUL character, not only by a NULL pointer
as our code assumed so far.
That led to a buffer overrun in `make_environment_block()` when running
`git-remote-https` in `mintty` (because `curl_global_init()` added the
`CHARSET` environment variable *outside* of `mingw_putenv()`, ending the
environment in a pointer to an empty string).
Side note for future debugging on Windows: when running programs in
`mintty`, the standard input/output/error is not connected to a Win32
Console, but instead is pipe()d. That means that even stderr may not be
written completely before a crash, but has to be fflush()ed explicitly.
For example, when debugging crashes, the developer should insert an
`fflush(stderr);` at the end of the `error()` function defined in
usage.c.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
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>
It is unlikely that we have an empty environment, ever, but *if* we do,
when `environ_size - 1` is passed to `bsearchenv()` it is misinterpreted
as a real large integer.
To make the code truly defensive, refuse to do anything at all if the
size is negative (which should not happen, of course).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
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>
The unsetenv code has no idea to update our environ_size, therefore
causing segmentation faults when environment variables are removed
without compat/mingw.c's knowing (MinGW's optimized lookup would try
to strcmp() against NULL in such a case).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
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>
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
Note that the test cannot rely on the presence of short names, as they
are not enabled by default except on the system drive.
[jes: adjusted test number to avoid conflicts, reinstated && chain,
adjusted test to work without short names]
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>
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]
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>
[jes: adjusted test number to avoid conflicts, fixed non-portable use of
the 'export' statement, fixed broken && chain]
Signed-off-by: Doug Kelly <dougk.ff7@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
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>
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>
In December 2016 and January 2017, we revamped the Windows-specific
`isatty()` handling, replacing a hack by a more robust solution.
This patch is a follow-up we realized was necessary already in March
2017, but forgot to contribute to core Git yet.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
When compiling Git with a runtime prefix (so that it can be installed
into any location, finding its libexec/ directory relative to the
location of the `git` executable), it is convenient to provide
"absolute" Unix-y paths e.g. for http.sslCAInfo, and have those absolute
paths be resolved relative to the runtime prefix.
This patch makes it so for Windows. It is up for discussion whether we
want this for other platforms, too, as long as building with
RUNTIME_PREFIX.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
On Windows, it is more common than on other platforms to "cross-compile"
32-bit binaries on a 64-bit machine. It is even possible to compile
32-bit binaries and 64-bit binaries in the same worktree, as the CFLAGS
differ, triggering a rebuild.
Except for the resource file, which does not need the CFLAGS. Let's work
around that.
This patch has been carried in Git for Windows for well over a year now,
and while it is not interesting to non-Windows platforms, it is time to
graduate to core Git.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This patch has been carried by Git for Windows for almost two years. It
makes loading system libraries safer.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This patch series contains a couple of fixes revolving around testing
an installed Git, via GIT_TEST_INSTALLED=/path/to/git.
The original motivation for these patches is that Git for Windows wants
to provide a version where the Unix shell scripts are interpreted by
BusyBox (to reduce the footprint on disk, mainly), and we want to verify
that this actually works, and is not perchance missing any Unix shell
tool that is present in the Git for Windows SDK but is missing from the
installed set of files.
While the BusyBox-based Git for Windows is not ready for prime time,
this here patch series is, and might be useful for packagers who want to
verify a similar scenario.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
We newly handle isatty() by special-casing the stdin/stdout/stderr file
descriptors, caching the return value. However, we missed the case where
dup2() overrides the respective file descriptor.
That poses a problem e.g. where the `show` builtin asks for a pager very
early, the `setup_pager()` function sets the pager depending on the
return value of `isatty()` and then redirects stdout. Subsequently,
`cmd_log_init_finish()` calls `setup_pager()` *again*. What should
happen now is that `isatty()` reports that stdout is *not* a TTY and
consequently stdout should be left alone.
Let's override dup2() to handle this appropriately.
This fixes https://github.com/git-for-windows/git/issues/1077
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
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>
When we access IPv6-related functions, we load the corresponding system
library using the `LoadLibrary()` function, which is not the recommended
way to load system libraries.
In practice, it does not make a difference: the `ws2_32.dll` library
containing the IPv6 functions is already loaded into memory, so
LoadLibrary() simply reuses the already-loaded library.
Still, recommended way is recommended way, so let's use that instead.
While at it, also adjust the code in contrib/ that loads system libraries.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
In the bin-wrappers/* scripts, we already take pains to use `git.exe`
rather than `git`, as this could pick up the wrong thing on Windows
(i.e. if there exists a `git` file or directory in the build directory).
Now we do the same in the tests' start-up code.
This also helps when testing an installed Git, as there might be even
more likely some stray file or directory in the way.
Note: the only way we can record whether the `.exe` suffix is by writing
it to the `GIT-BUILD-OPTIONS` file and sourcing it at the beginning of
`t/test-lib.sh`. This is not a requirement introduced by this patch, but
we move the call to be able to use the `$X` variable that holds the file
extension, if any.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
We really only need the test helpers in that case, but that is not what
we test for. So let's skip the test for now when we know that we want to
test an installed Git.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
It makes very, very little sense to test the built git-sh-i18n when the
user asked specifically to test another one.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
It really makes very, very little sense to use a different git
executable than the one the caller indicated via setting the environment
variable GIT_TEST_INSTALLED.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
We really need to be able to find the test helpers... Really. This
change was forgotten when we moved the test helpers into t/helper/
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This topic branch teaches Git to accept UNC paths of the form
file://host/share/repository.git.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This topic branch brings support for choosing cURL's SSL backend at
runtime via http.sslBackend, based on patches already submitted to the
cURL project and backported to cURL 7.54.1 as used in Git for Windows'
SDK.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This backports f31d23a399 (Merge branch 'bw/config-h', 2017-06-24) from
upstream Git's `master` branch, plus a patch that seems to be required
to let the test suite pass.
This topic branch fixes problems when looking up aliases in worktrees.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This topic branch addresses a problem identified in
https://github.com/git-for-windows/git/issues/439: while
cloning/fetching/pushing from "POSIX-ified UNC paths" (i.e. UNC paths
whose backslashes have been converted to forward slashes) works for some
time now, true UNC paths (with backslashes left intact) were handled
incorrectly. Example:
git clone //myserver/folder/repo.git
works, but
git clone \\myserver\folder\repo.git
(in CMD; in Git Bash, the backslashes would need to be doubled) used to
fail. The reason was an unexpected difference in command-line handling
between Win32 executables and MSYS2 ones (such as the shell that is used
by git-clone.exe to spawn git-upload-pack.exe).
This topic branch features a workaround *just* for the case where Git
passes stuff through sh.exe (which covers quite a few use cases,
though).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
