Bigger writes to network drives on Windows XP fail. Cap them at 31MB to
allow them to succeed. Callers need to be prepared for write() calls
that do less work than requested anyway.
On local drives, write() calls are translated to WriteFile() calls with
a cap of 64KB on Windows XP and 256KB on Vista. Thus a cap of 31MB won't
affect the number of WriteFile() calls which do the actual work. There's
still room for some other version of Windows to use a chunk size of 1MB
without increasing the number of system calls.
Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A caller of start_command can set the member 'dir' to a directory to
request that the child process starts with that directory as CWD. The first
user of this feature was added recently in eee49b6 (Teach diff --submodule
and status to handle .git files in submodules).
On Windows, we have been lazy and had not implemented support for this
feature, yet. This fixes the shortcoming.
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
On Windows, the equivalent of "/dev/null" is "nul". This implements
compatibility wrappers around fopen() and freopen() that check for this
particular file name.
The new tests exercise code paths where this is relevant.
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This patch implements native to Windows subset of pthreads API used by Git.
It allows to remove Pthreads for Win32 dependency for MSVC, msysgit and
Cygwin.
[J6t: If the MinGW build was built as part of the msysgit build
environment, then threading was already enabled because the
pthreads-win32 package is available in msysgit. With this patch, we can now
enable threaded code unconditionally.]
Signed-off-by: Andrzej K. Haczewski <ahaczewski@gmail.com>
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In particular, the following warning is issued while compiling
compat/msvc.c:
...mingw.c(223) : warning C4133: 'function' : incompatible \
types - from '_stati64 *' to '_stat64 *'
which relates to a call of _fstati64() in the mingw_fstat()
function definition.
This is caused by various layers of macro magic and attempts to
avoid macro redefinition compiler warnings. For example, the call
to _fstati64() mentioned above is actually a call to _fstat64(),
and expects a pointer to a struct _stat64 rather than the struct
_stati64 which is passed to mingw_fstat().
The definition of struct _stati64 given in compat/msvc.h had the
same "shape" as the definition of struct _stat64, so the call to
_fstat64() does not actually cause any runtime errors, but the
structure types are indeed incompatible.
In order to avoid the compiler warning, we add declarations for the
mingw_lstat() and mingw_fstat() functions and supporting macros to
msvc.h, suppressing the corresponding declarations in mingw.h, so
that we can use the appropriate structure type (and function) names
from the msvc headers.
Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When stdin, stdout, or stderr must be redirected for a child process that
on Windows is spawned using one of the spawn() functions of Microsoft's
C runtime, then there is no choice other than to
1. make a backup copy of fd 0,1,2 with dup
2. dup2 the redirection source fd into 0,1,2
3. spawn
4. dup2 the backup back into 0,1,2
5. close the backup copy and the redirection source
We used this idiom as well -- but we are not using the spawn() functions
anymore!
Instead, we have our own implementation. We had hardcoded that stdin,
stdout, and stderr of the child process were inherited from the parent's
fds 0, 1, and 2. But we can actually specify any fd.
With this patch, the fds to inherit are passed from start_command()'s
WIN32 section to our spawn implementation. This way, we can avoid the
backup copies of the fds.
The backup copies were a bug waiting to surface: The OS handles underlying
the dup()ed fds were inherited by the child process (but were not
associated with a file descriptor in the child). Consequently, the file or
pipe represented by the OS handle remained open even after the backup copy
was closed in the parent process until the child exited.
Since our implementation of pipe() creates non-inheritable OS handles, we
still dup() file descriptors in start_command() because dup() happens to
create inheritable duplicates. (A nice side effect is that the fd cleanup
in start_command is the same for Windows and Unix and remains unchanged.)
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The IPv6 support functions are loaded dynamically, to maintain backwards
compatibility with versions of Windows prior to XP, and fallback wrappers
are provided, implemented in terms of gethostbyname and gethostbyaddr.
Signed-off-by: Martin Storsjo <martin@martin.st>
Acked-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When the NO_MMAP build variable is set, the msvc linker complains:
error LNK2001: unresolved external symbol _getpagesize
The msvc libraries do not define the getpagesize() function,
so we move the mingw_getpagesize() implementation from the
conditionally built win32mmap.c file to mingw.c.
Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
SSL_set_fd (and friends) expects a OS file handle on Windows, not
a file descriptor as on UNIX(-ish).
This patch makes the Windows version of SSL_set_fd behave like the
UNIX versions, by calling _get_osfhandle on it's input.
Signed-off-by: Erik Faye-Lund <kusmabite@gmail.com>
Acked-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Centralize the include of windows.h in git-compat-util.h, turn on
WIN32_LEAN_AND_MEAN to avoid including plenty of other header files
which is not needed in Git. Also ensure we load winsock2.h first,
so we don't load the older winsock definitions at a later stage,
since they contain duplicate definitions.
When moving windows.h into git-compat-util.h, we need to protect
the definition of struct pollfd in mingw.h, since this file is used
by both MinGW and MSVC, and the latter defines this struct in
winsock2.h.
We need to keep the windows.h include in compat/win32.h, since its
shared by both MinGW and Cygwin, and we're not touching Cygwin in
this commit. The include in git-compat-util.h is protected with an
ifdef WIN32, which is not the case when compiling for Cygwin.
Signed-off-by: Marius Storm-Olsen <mstormo@gmail.com>
Acked-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
MinGW set the _CRT_fmode to set both the default fmode and _O_BINARY on
stdin/stdout/stderr. Rather use the main() define in mingw.h to set this
for both MinGW and MSVC.
This will ensure that a MinGW and MSVC build will handle input and output
identically.
Signed-off-by: Marius Storm-Olsen <mstormo@gmail.com>
Acked-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Previously, it would not be possible to call start_command twice for the
same struct child_process that has env set.
The fix is achieved by moving the loop that modifies the environment block
into a helper function. This also allows us to make two other helper
functions static.
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Windows does not have signals. At least they cannot be diagnosed by the
parent process; all that the parent process can observe is the exit code.
This also adds a dummy definition of WTERMSIG.
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
For some reason, MinGW's bash cannot reliably detect failure of the child
process if a negative value is passed to exit(). This fixes it by
truncating the exit code in all calls of exit().
This issue was worked around in run_builtin() of git.c (2488df84 builtin
run_command: do not exit with -1, 2007-11-15). This workaround is no longer
necessary and is reverted.
Suggested-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The original readdir implementation was fast, but didn't
support the d_type. This means that git would do additional
lstats for each entry, to figure out if the entry was a
directory or not. This unneedingly slowed down many
operations, since Windows API provides this information
directly when walking the directories.
By running this implementation on Moe's repo structure:
mkdir bummer && cd bummer; for ((i=0;i<100;i++)); do
mkdir $i && pushd $i;
for ((j=0;j<1000;j++)); do echo "$j" >$j; done;
popd;
done
We see the following speedups:
git add .
-------------------
old: 00:00:23(.087)
new: 00:00:21(.512) 1.07x
git status
-------------------
old: 00:00:03(.306)
new: 00:00:01(.684) 1.96x
git clean -dxf
-------------------
old: 00:00:01(.918)
new: 00:00:00(.295) 6.50x
Signed-off-by: Marius Storm-Olsen <marius@trolltech.com>
Signed-off-by: Steffen Prohaska <prohaska@zib.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We need getpass() to activate curl on MinGW. Although the default
Makefile currently has 'NO_CURL = YesPlease', msysgit releases do
provide curl support, so getpass() is used.
[spr: - edited commit message.
- squashed commit that provides getpass() declaration.]
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Steffen Prohaska <prohaska@zib.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Git's source code expects waitpid() to return a signed int status.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Steffen Prohaska <prohaska@zib.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add USE_WIN32_MMAP which triggers the use of windows' native
file memory mapping functionality in git_mmap()/git_munmap() functions.
As git functions currently use mmap with MAP_PRIVATE set only, this
implementation supports only that mode for now.
On Windows, offsets for memory mapped files need to match the allocation
granularity. Take this into account when calculating the packed git-
windowsize and file offsets. At the moment, the only function which makes
use of offsets in conjunction with mmap is use_pack() in sha1-file.c.
Git fast-import's code path tries to map a portion of the temporary
packfile that exceeds the current filesize, i.e. offset+length is
greater than the filesize. The NO_MMAP code worked with that since pread()
just reads the file content until EOF and returns gracefully, while
MapViewOfFile() aborts the mapping and returns 'Access Denied'.
Working around that by determining the filesize and adjusting the length
parameter.
Signed-off-by: Janos Laube <janos.dev@gmail.com>
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When overriding the identifier "stat" so that "struct stat" will be
substituted with "struct _stati64" everywhere, I tried to fix the calls
to the _function_ stat(), too, but I forgot to change the earlier
attempt "stat64" to "_stati64" there.
So, the stat() calls were overridden by calls to _stati64() instead.
Unfortunately, there is a function _stati64() so that I missed that
calls to stat() were not actually overridden by calls to mingw_lstat(),
but t4200-rerere.sh showed the error.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Acked-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The type 'off_t' should be used everywhere so that the bit-depth of that
type can be adjusted in the standard C library, and you just need to
recompile your program to benefit from the extended precision.
Only that it was not done that way in the MS runtime library.
This patch reroutes off_t to off64_t and provides the other necessary
changes so that finally, clones larger than 2 gigabyte work on Windows
(provided you are on a file system that allows files larger than 2gb).
Initial patch by Sickboy <sb@dev-heaven.net>.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Acked-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We had defined some SIG_FOO macros that appear in the code, but that are
not supported on Windows, in order to make the code compile. But a
subsequent change will assert that a signal number is non-zero. We now
use the signal numbers that are commonly used on POSIX systems.
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This reverts commit fc2ded5b08.
As we do not need the member in struct stat, we do not need to have a
custom "struct mingw_stat" anymore.
Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Some platforms do not have st_blocks member in "struct stat"; mingw
already emulates it by rounding it up to closest 512-byte blocks (even
though it could overcount when a file has holes).
The reason to use the member is only to figure out how many kilobytes the
files occupy on-disk, so give a helper function in git-compat-util.h to
compute this value.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Acked-by: Johannes Sixt <johannes.sixt@telecom.at>
With MinGW's
gcc.exe (GCC) 3.4.5 (mingw special)
GNU ld version 2.17.50 20060824
the old define caused link errors:
git.o: In function `main':
C:/msysgit/git/git.c:500: undefined reference to `mingw_main'
collect2: ld returned 1 exit status
The modified define works.
Signed-off-by: Steffen Prohaska <prohaska@zib.de>
Acked-by: Johannes Sixt <johannes.sixt@telecom.at>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since the exec-path on Windows is derived from the program invocation path,
we must ensure that argv[0] always has a path. Unfortunately, if a program
is invoked from CMD, argv[0] has no path. But on the other hand, the
C runtime offers a global variable, _pgmptr, that always has the full path
to the program. We hook into main() with a preprocessor macro, where we
replace argv[0].
Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This adds only the minimum necessary to keep git pull/merge's diffstat from
wrapping. Notably absent is support for the K (erase) operation, and support
for POSIX write.
Signed-off-by: Peter Harris <git@peter.is-a-geek.org>
Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The system's default browser for displaying HTML help pages is now used
directly on Windows, instead of launching git-web--browser, which
requires a Unix shell. Avoiding MSYS' bash when possible is good
because it avoids potential path translation issues. In this case it is
not too hard to avoid launching a shell, so let's avoid it.
The Windows-specific code is implemented in compat/mingw.c to avoid
platform-specific code in the main code base. On Windows, open_html is
provided as a define. If open_html is not defined, git-web--browse is
used. This approach avoids platform-specific ifdefs by using
per-function ifdefs. The "ifndef open_html" together with the
introductory comment should sufficiently warn developers, so that they
hopefully will not break this mechanism.
Signed-off-by: Steffen Prohaska <prohaska@zib.de>
Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
On Windows, ntohl() returns unsigned long. On Unix it returns
uint32_t. This makes choosing a suitable printf format string
hard.
This commit introduces a mingw specific helper function
git_ntohl() that casts to unsigned int before returning. This
makes gcc's printf format check happy. It should be safe because
we expect ntohl to use 32-bit numbers.
Signed-off-by: Steffen Prohaska <prohaska@zib.de>
Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
Windows's struct stat does not have a st_blocks member. Since we already
have our own stat/lstat/fstat implementations, we can just as well use
a customized struct stat. This patch introduces just that, and also fills
in the st_blocks member. On the other hand, we don't provide members that
are never used.
Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
This is a necessary pendant to our lstat implementation: MSVCRT's
implementations of lstat and utime do some adjustments if daylight
saving time is in effect, but our lstat implementation doesn't do these
adjustments and report the correct UTC time. With this implementation
we omit the adjustments in utime() as well and always write UTC.
Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
This gives us a significant speedup when adding, committing and stat'ing files.
Also, since Windows doesn't really handle symlinks, we let stat just uses lstat.
We also need to replace fstat, since our implementation and the standard stat()
functions report slightly different timestamps, possibly due to timezones.
We simply report UTC in our implementation, and do our FILETIME to time_t
conversion based on the document at http://support.microsoft.com/kb/167296.
With Moe's repo structure (100K files in 100 dirs, containing 2-4 bytes)
mkdir bummer && cd bummer; for ((i=0;i<100;i++)); do
mkdir $i && pushd $i;
for ((j=0;j<1000;j++)); do echo "$j" >$j; done;
popd;
done
We get the following performance boost:
With normal lstat & stat Custom lstat/fstat
------------------------ ------------------------
Command: git init Command: git init
------------------------ ------------------------
real 0m 0.047s real 0m 0.063s
user 0m 0.031s user 0m 0.015s
sys 0m 0.000s sys 0m 0.015s
------------------------ ------------------------
Command: git add . Command: git add .
------------------------ ------------------------
real 0m19.390s real 0m12.031s 1.6x
user 0m 0.015s user 0m 0.031s
sys 0m 0.030s sys 0m 0.000s
------------------------ ------------------------
Command: git commit -a.. Command: git commit -a..
------------------------ ------------------------
real 0m30.812s real 0m16.875s 1.8x
user 0m 0.015s user 0m 0.015s
sys 0m 0.000s sys 0m 0.015s
------------------------ ------------------------
3x Command: git-status 3x Command: git-status
------------------------ ------------------------
real 0m11.860s real 0m 5.266s 2.2x
user 0m 0.015s user 0m 0.015s
sys 0m 0.015s sys 0m 0.015s
real 0m11.703s real 0m 5.234s
user 0m 0.015s user 0m 0.015s
sys 0m 0.000s sys 0m 0.000s
real 0m11.672s real 0m 5.250s
user 0m 0.031s user 0m 0.015s
sys 0m 0.000s sys 0m 0.000s
------------------------ ------------------------
Command: git commit... Command: git commit...
(single file) (single file)
------------------------ ------------------------
real 0m14.234s real 0m 7.735s 1.8x
user 0m 0.015s user 0m 0.031s
sys 0m 0.000s sys 0m 0.000s
Signed-off-by: Marius Storm-Olsen <mstormo_git@storm-olsen.com>
Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
The problem with Windows's own implementation is that it tries to be
clever when a console program is invoked from a GUI application: In this
case it sometimes automatically allocates a new console window. As a
consequence, the IO channels of the spawned program are directed to the
console, but the invoking application listens on channels that are now
directed to nowhere.
In this implementation we use the lowlevel facilities of CreateProcess(),
which offers a flag to tell the system not to open a console. As a side
effect, only stdin, stdout, and stderr channels will be accessible from
C programs that are spawned. Other channels (file handles, pipe handles,
etc.) are still inherited by the spawned program, but it doesn't get
enough information to access them.
Johannes Schindelin integrated path quoting and unified the various
*execv* and *spawnv* helpers. Eric Raible suggested to also quote '{'.
Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
gethostbyname() is the first function that calls into the Winsock library,
and it is wrapped only to initialize the library.
socket() is wrapped for two reasons:
- Windows's socket() creates things that are like low-level file handles,
and they must be converted into file descriptors first.
- And these handles cannot be used with plain ReadFile()/WriteFile()
because they are opened for "overlapped IO". We have to use WSASocket()
to create non-overlapped IO sockets.
connect() must be wrapped because Windows's connect() expects the low-level
sockets, not file descriptors, and we must first unwrap the file descriptor
before we can pass it on to Windows's connect().
Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
On Windows, we have spawnv() variants to run a child process instead of
fork()/exec(). In order to attach pipe ends to stdin, stdout, and stderr,
we have to use this idiom:
save1 = dup(1);
dup2(pipe[1], 1);
spawnv();
dup2(save1, 1);
close(pipe[1]);
assuming that the descriptors created by pipe() are not inheritable.
Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
On Unix the idiom to use a pipe is as follows:
pipe(fd);
pid = fork();
if (!pid) {
dup2(fd[1], 1);
close(fd[1]);
close(fd[0]);
...
}
close(fd[1]);
i.e. the child process closes the both pipe ends after duplicating one
to the file descriptors where they are needed.
On Windows, which does not have fork(), we never have an opportunity to
(1) duplicate a pipe end in the child, (2) close unused pipe ends. Instead,
we must use this idiom:
save1 = dup(1);
pipe(fd);
dup2(fd[1], 1);
spawn(...);
dup2(save1, 1);
close(fd[1]);
i.e. save away the descriptor at the destination slot, replace by the pipe
end, spawn process, restore the saved file.
But there is a problem: Notice that the child did not only inherit the
dup2()ed descriptor, but also *both* original pipe ends. Although the one
end that was dup()ed could be closed before the spawn(), we cannot close
the other end - the child inherits it, no matter what.
The solution is to generate non-inheritable pipes. At the first glance,
this looks strange: The purpose of pipes is usually to be inherited to
child processes. But notice that in the course of actions as outlined
above, the pipe descriptor that we want to inherit to the child is
dup2()ed, and as it so happens, Windows's dup2() creates inheritable
duplicates.
Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
When an external git command is invoked, it can be a Bourne shell script.
This patch looks into the command file to see whether it is one.
In this case, the command line is rearranged to invoke the shell
with the proper arguments.
With this change, scripted git commands work. Command line arguments
to those scripts cannot be complex (contain spaces or double-quotes), yet.
Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
The timer is implemented using a thread that calls the signal handler
at regular intervals.
We also replace Windows's signal() function because we must intercept
that SIGALRM is set (which is used when a timer is canceled).
Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
Since GIT calls into Microsoft's MSVCRT.DLL, it must use the printf
format that this DLL uses for 64-bit integers, which is %I64u instead
of %llu.
Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
Windows's rename() is based on the MoveFile() API, which fails if the
destination exists. Here we work around the problem by using MoveFileEx().
Furthermore, the posixly correct error is returned if the destination is
a directory.
The implementation is still slightly incomplete, however, because of the
missing error code translation: We assume that the failure is due to
permissions.
Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
On Windows, read-only files cannot be deleted. To make sure that
deletion does not fail because of this, always call chmod() before
unlink().
Signed-off-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
The wrapper does two things:
- Requests to open /dev/null are redirected to open the nul pseudo file.
- A request to open a file that currently exists as a directory on
Windows fails with EACCES; this is changed to EISDIR.
Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
GIT's guts work with a forward slash as a path separators. We do not change
that. Rather we make sure that only "normalized" paths enter the depths
of the machinery.
We have to translate backslashes to forward slashes in the prefix and in
command line arguments. Fortunately, all of them are passed through
functions in setup.c.
A macro has_dos_drive_path() is defined that checks whether a path begins
with a drive letter+colon combination. This predicate is always false on
Unix. Another macro is_dir_sep() abstracts that a backslash is also a
directory separator on Windows.
Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
With this change GIT can be compiled and linked using MinGW. Builtins
that only read the repository such as the log family and grep already
work.
Simple stubs are provided for a number of functions that the Windows C
runtime does not offer. They will be completed in later patches.
However, a fix for the snprintf/vsnprintf replacement is applied here
to avoid buffer overflows.
Dmitry Kakurin pointed out that access(..., X_OK) would always fails on
Vista and suggested the -D__USE_MINGW_ACCESS workaround.
Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>