A potential but unlikely buffer overflow in Windows port has been
fixed.
* mk/mingw-winansi-ttyname-termination-fix:
mingw: consider that UNICODE_STRING::Length counts bytes
Git for Windows has carried a patch that depended on internals
of MSVC runtime, but it does not work correctly with recent MSVC
runtime. A replacement was written originally for compiling
with VC++. The patch in this message is a backport of that
replacement, and it also fixes the previous attempt to make
isatty() tell that /dev/null is *not* an interactive terminal.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Tested-by: Beat Bolli <dev+git@drbeat.li>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Git only colours the output and uses pagination if isatty() returns 1.
MSYS2 and Cygwin emulate pseudo terminals via named pipes, meaning that
isatty() returns 0.
f7f90e0f4f (mingw: make isatty() recognize MSYS2's pseudo terminals
(/dev/pty*), 2016-04-27) fixed this for MSYS2 terminals, but not for
Cygwin.
The named pipes that Cygwin and MSYS2 use are very similar. MSYS2 PTY pipes
are called 'msys-*-pty*' and Cygwin uses 'cygwin-*-pty*'. This commit
modifies the existing check to allow both MSYS2 and Cygwin PTY pipes to be
identified as TTYs.
Note that pagination is still broken when running Git for Windows from
within Cygwin, as MSYS2's less.exe is spawned (and does not like to
interact with Cygwin's PTY).
This partially fixes https://github.com/git-for-windows/git/issues/267
Signed-off-by: Alan Davies <alan.n.davies@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When determining whether a handle corresponds to a *real* Win32 Console
(as opposed to, say, a character device such as /dev/null), we use the
GetConsoleOutputBufferInfo() function as a tell-tale.
However, that does not work for *input* handles associated with a
console. Let's just use the GetConsoleMode() function for input handles,
and since it does not work on output handles fall back to the previous
method for those.
This patch prepares for using is_console() instead of my previous
misguided attempt in cbb3f3c9b1 (mingw: intercept isatty() to handle
/dev/null as Git expects it, 2016-12-11) that broke everything on
Windows.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
UNICODE_STRING::Length field means size of buffer in bytes[1],
despite of buffer itself being array of wchar_t. Because of that
terminating zero is placed twice as far. Fix it.
[1] https://msdn.microsoft.com/en-us/library/windows/desktop/aa380518.aspx
Signed-off-by: Max Kirillov <max@max630.net>
Acked-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When Git's source code calls isatty(), it really asks whether the
respective file descriptor is connected to an interactive terminal.
Windows' _isatty() function, however, determines whether the file
descriptor is associated with a character device. And NUL, Windows'
equivalent of /dev/null, is a character device.
Which means that for years, Git mistakenly detected an associated
interactive terminal when being run through the test suite, which
almost always redirects stdin, stdout and stderr to /dev/null.
This bug only became obvious, and painfully so, when the new
bisect--helper entered the `pu` branch and made the automatic build & test
time out because t6030 was waiting for an answer.
For details, see
https://msdn.microsoft.com/en-us/library/f4s0ddew.aspx
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The recently introduced developer flags identified a couple of
old-style function declarations in the Windows-specific code where
the parameter list was left empty instead of specifying "void"
explicitly. Let's just fix them.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
MSYS2 emulates pseudo terminals via named pipes, and isatty() returns 0
for such file descriptors. Therefore, some interactive functionality
(such as launching a pager, asking if a failed unlink should be repeated
etc.) doesn't work when run in a terminal emulator that uses MSYS2's
ptys (such as mintty).
However, MSYS2 uses special names for its pty pipes ('msys-*-pty*'),
which allows us to distinguish them from normal piped input / output.
On startup, check if stdin / stdout / stderr are connected to such pipes
using the NtQueryObject API from NTDll.dll. If the names match, adjust
the flags in MSVCRT's ioinfo structure accordingly.
Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
HANDLE is defined internally as a void *, but in many cases it is
actually guaranteed to be a 32-bit integer. In these cases, GCC should
not warn about a cast of a pointer to an integer of a different type
because we know exactly what we are doing.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
MSys2 already defines the _CONSOLE_FONT_INFOEX structure.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We sometimes sprintf into fixed-size buffers when we know
that the buffer is large enough to fit the input (either
because it's a constant, or because it's numeric input that
is bounded in size). Likewise with strcpy of constant
strings.
However, these sites make it hard to audit sprintf and
strcpy calls for buffer overflows, as a reader has to
cross-reference the size of the array with the input. Let's
use xsnprintf instead, which communicates to a reader that
we don't expect this to overflow (and catches the mistake in
case we do).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
As of "Win32: Thread-safe windows console output", child processes may
print to the console even if stdout has been redirected to a file. E.g.:
git config tar.cat.command "cat"
git archive -o test.cat HEAD
Detecting whether stdout / stderr point to our console pipe is currently
based on the assumption that OS HANDLE values are never reused. This is
apparently not true if stdout / stderr is replaced via dup2() (as in
builtin/archive.c:17).
Instead of comparing handle values, check if the file descriptor isatty()
backed by a pipe OS handle. This is only possible by swapping the handles
in MSVCRT's internal data structures, as we do in winansi_init().
Reported-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
As of "Win32: Thread-safe windows console output", git-log no longer
terminates when the pager process dies. This is due to disabling buffering
for the replaced stdout / stderr streams. Git-log will periodically fflush
stdout (see write_or_die.c/mayble_flush_or_die()), but with no buffering,
this is a NOP that always succeeds (so we never detect the EPIPE error).
Exchange the original console handles with our console thread pipe handles
by accessing the internal MSVCRT data structures directly (which are
exposed via __pioinfo for some reason).
Implement this with minimal assumptions about the actual data structure to
make it work with different (hopefully even future) MSVCRT versions.
While messing with internal data structures is ugly, this patch solves the
problem at the source instead of adding more workarounds. We no longer need
the special winansi_isatty override, and the limitations documented in
"Win32: Thread-safe windows console output" are gone (i.e. fdopen(1/2)
returns unbuffered streams now, and isatty() for duped console file
descriptors works as expected).
Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Stepan Kasal <kasal@ucw.cz>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Winansi.c has many static variables that are accessed and modified from
the [v][f]printf / fputs functions overridden in the file. This may cause
multi threaded git commands that print to the console to produce corrupted
output or even crash.
Additionally, winansi.c doesn't override all functions that can be used to
print to the console (e.g. fwrite, write, fputc are missing), so that ANSI
escapes don't work properly for some git commands (e.g. git-grep).
Instead of doing ANSI emulation in just a few wrapped functions on top of
the IO API, let's plug into the IO system and take advantage of the thread
safety inherent to the IO system.
Redirect stdout and stderr to a pipe if they point to the console. A
background thread reads from the pipe, handles ANSI escape sequences and
UTF-8 to UTF-16 conversion, then writes to the console.
The pipe-based stdout and stderr replacements must be set to unbuffered, as
MSVCRT doesn't support line buffering and fully buffered streams are
inappropriate for console output.
Due to the byte-oriented pipe, ANSI escape sequences and multi-byte UTF-8
sequences can no longer be expected to arrive in one piece. Replace the
string-based ansi_emulate() with a simple stateful parser (this also fixes
colored diff hunk headers, which were broken as of commit 2efcc977).
Override isatty to return true for the pipes redirecting to the console.
Exec/spawn obtain the original console handle to pass to the next process
via winansi_get_osfhandle().
All other overrides are gone, the default stdio implementations work as
expected with the piped stdout/stderr descriptors.
Global variables are either initialized on startup (single threaded) or
exclusively modified by the background thread. Threads communicate through
the pipe, no further synchronization is necessary.
The background thread is terminated by disonnecting the pipe after flushing
the stdio and pipe buffers. This doesn't work for anonymous pipes (created
via CreatePipe), as DisconnectNamedPipe only works on the read end, which
discards remaining data. Thus we have to setup the pipe manually, with the
write end beeing the server (opened with CreateNamedPipe) and the read end
the client (opened with CreateFile).
Limitations: doesn't track reopened or duped file descriptors, i.e.:
- fdopen(1/2) returns fully buffered streams
- dup(1/2), dup2(1/2) returns normal pipe descriptors (i.e. isatty() =
false, winansi_get_osfhandle won't return the original console handle)
Currently, only the git-format-patch command uses xfdopen(xdup(1)) (see
"realstdout" in builtin/log.c), but works well with these limitations.
Many thanks to Atsushi Nakagawa <atnak@chejz.com> for suggesting and
reviewing the thread-exit-mechanism.
Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Stepan Kasal <kasal@ucw.cz>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Unicode console output won't display correctly with default settings
because the default console font ("Terminal") only supports the system's
OEM charset. Unfortunately, this is a user specific setting, so it cannot
be easily fixed by e.g. some registry tricks in the setup program.
This change prints a warning on exit if console output contained non-ascii
characters and the console font is supposedly not a TrueType font (which
usually have decent Unicode support).
Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Stepan Kasal <kasal@ucw.cz>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
GetStdHandle(STD_OUTPUT_HANDLE) doesn't work for stderr if stdout is
redirected. Use _get_osfhandle of the FILE* instead.
_isatty() is true for all character devices (including parallel and serial
ports). Check return value of GetConsoleScreenBufferInfo instead to
reliably detect console handles (also don't initialize internal state from
an uninitialized CONSOLE_SCREEN_BUFFER_INFO structure if the function
fails).
Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Stepan Kasal <kasal@ucw.cz>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
WriteConsoleW seems to be the only way to reliably print unicode to the
console (without weird code page conversions).
Also redirects vfprintf to the winansi.c version.
Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Stepan Kasal <kasal@ucw.cz>
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>
The function FillConsoleOutputCharacterA() was pretty content in XP to take a NULL
pointer if we did not want to store the number of written columns. In Windows 7,
it crashes, but only when called from within Git Bash, not from within cmd.exe.
Go figure.
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>
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>
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>
