- Using memcmp() to compare structure such as INPUT_RECORD is not
correct manner because padding may not be initialized. This patch
stops to use memcmp() for comparison of INPUT_RECORD.
- dwControlKeyState also may be null'ed on WriteConsoleInputW().
Therefore ignore it in event comparison as well as wVirtualKeyCode
and wVirtualScanCode.
- The commit "Cygwin: console: Improve the code to avoid typeahead
key swapping." did not solve the problem enough. Two unexpected
things happen.
(1) wVirtualKeyCode and wVirtualScanCode of readback key event may
be null'ed even if they are not zero on WriteConsoleInputW().
Therefore, memcmp() may report the event sequence is not equal.
(2) WriteConsoleInputW() may not be atomic. The event sequence
which is written by WriteConsoleInputW() may be inserted by
key input in the middle of the sequence. Current code gives
up to fix in this situation.
This patch should fix that issue.
- This patch revises the acquiring/releasing timing for attach_mutex
to make the period in which it is being acquired shorter. Further,
acquiring/releasing are added to where they are missing but needed.
- In fhandler_console::cons_master_thread(), a struct which has
only a static function is used. In this case, struct instance
is not necessary. So with this patch, the static function is
invoked without creating instance.
- The commit "Cygwin: console: Prevent the order of typeahead input
from swapped." did not fully resolve the issue. If keys are typed
during input buffer fix, the order of key event may be swapped.
This patch fixes the issue again.
- If a lot of keys are typed very quickly in the app which does
not read console, the order of input keys in console input buffer
occasionally swapped. Although this extremely rarely happens,
is obviously a bug of cons_master_thread. This patch fixes the
issue.
- After some recent changes for special keys handling break the
apps which open pty (such as script command). If the app which
opens pty is executed in console, the following issues occur.
1) If the script command was started from non-cygwin shell
(such as cmd.exe), another cygwin app started in pty slave
cannot receive Ctrl-C.
2) If non-cygwin app is executed in pty slave, the app which
opened the pty (e.g. script command) crashes by Ctrl-C.
This patch fixes these issues.
- The recent change by the commit "Cygwin: console: Redesign handling
of special keys." breaks the handling of CTRL_BREAK_EVENT. The login
shell in console exits on Ctrl-Break key. This patch fixes the issue.
- The inferior of the GDB cannot be continued after SIGINT even
though nopass option is set. This seems because cygwin GDB does
not support hooking cygwin signal. Therefore, a workaround for
GDB is added. With this patch, only CTRL_C_EVENT is sent to the
GDB inferior by Ctrl-C and sending SIGINT is omitted. Note that
"handle SIGINT (no)pass" command does not take effect even with
or without this patch.
- This patch rearranges the cooperation between cons_master_thread,
line_edit, and ctrl_c_handler so that only one of them operates
at the same time. Since these handle Ctrl-C individually, so the
signal may be sent multiple times to the process. This patch fixes
the issue.
- This patch fixes the handle leak which occurs when exec() fails
with an error. The duplicated handles will be closed when the
exec'ed process is terminated. However, if exec() fails, the code
path does not reach to the code closing the duplicated handles.
To implement this fix more appropriately, the setup, cleanup and
closing pty codes which was previously located in spawn.cc are
encapsulated into the fhandler_pty_slave class functions.
- Calling fix_tab_position() is necessary in Windows 10 with xterm
compatible mode enabled, because it has a problem that the tab
positions will be broken when the window size is changed. Fortunately,
this problem has been fixed in Windows 11. Therefore, with this patch,
necessity of fix_tab_position() call is determined by referring to
wincap.has_con_broken_tabs(), which is recently introduced.
- With this patch, all set_(in|out)put_mode() calls are rearranged
as follows.
1) Setup for cygwin apps, started from non-cygwin app, is done
in fhandler_console::post_open_setup(), which overrides
fhandler_base::post_open_setup() called from dtable.cc.
2) Cleanup for cygwin app is done in fhandler_console::close().
3) Setup for cygwin apps is also in fhandler_console::bg_check(),
which overrides fhandler_termios::bg_check(). This is called
on read(), write() and select() for console. It is necessary
if cygwin and non-cygwin apps are started simultaneously in
the same process group.
4) Setup for non-cygwin apps is done in spawn.cc via
fhandler_console::setup_console_for_non_cygwin_app().
5) Cleanup for non-cygwin app is done in spawn.cc vid
fhandler_console::cleanup_console_for_non_cygwin_app().
6) Setup for non-cygwin app started by GDB is done in
fhandler_console::set_console_mode_to_native().
7) No explicit cleanup for non-cygwin app started by GDB, because
console mode is automatically reset to tty::cygwin on read()/
write() in GDB thanks to 3).
- This patch commonize the code which processes special keys in pty
and console to improve maintanancibility. As a result, some small
bugs have been fixed.
- Currently, there is no chance to change console mode for non-cygwin
inferior of GDB. With this patch, the console mode is changed to
tty::native in CreateProcess() and ContinueDebugEvent() hooked in
fhandler_console.
- Currently, if cat is started from cmd.exe which is started in cygwin
console, Ctrl-C terminates not only cat but also cmd.exe. This also
happens in pty in which pseudo console is disabled. This patch fixes
the issue.
- Currently, ENABLE_INSERT_MODE and ENABLE_QUICK_EDIT_MODE are cleared
if cygwin is started in console. These flags will not be recovered
even when exiting from cygwin. Also note that if ENABLE_EXTENDED_FLAGS
is once unset, then the flag ENABLE_QUICK_EDIT_MODE it's associated
with will no longer be preserved. Unfortunately, we're accidentally
stepping on this in fhandler_console::set_input_mode().
This patch solves this by carrying forward these flags in the place
where it had been ignoring them. Since the previous behaviour of
leaving these flags unset would essentially maintain their existing
state, adding the carry-over of the flags now should not alter console
behaviour.
- Closing attach_mutex and recreating it causes the race issue
between pty and console codes. With this patch, attach_mutex
is created only once in a process which opens pty, and never
closed in order to avoid this issue.
Addresses:
https://cygwin.com/pipermail/cygwin-developers/2021-December/012548.html
- GDB inferior may be suspended while the inferior grabs mutex.
This causes deadlock in terminal I/O. With this patch, timeout
for waiting mutex is set to 0 for the debugger process when the
process calls CreateProcess() with DEBUG_PROCESS flag to avoid
deadlock. This may cause the race issue in GDB, however, there
is no other way than that.
Addresses:
https://cygwin.com/pipermail/cygwin-developers/2021-December/012542.html
When running Cygwin's Bash in the Windows Terminal (see
https://docs.microsoft.com/en-us/windows/terminal/ for details), Cygwin
is receiving keyboard input in the form of UTF-16 characters.
UTF-16 has that awkward challenge that it cannot map the full Unicode
range, and to make up for it, there are the ranges U+D800-U+DBFF and
U+DC00-U+DFFF which are illegal except when they come in a pair encoding
for Unicode characters beyond U+FFFF.
Cygwin does not handle such surrogate pairs correctly at the moment, as
can be seen e.g. when running Cygwin's Bash in the Windows Terminal and
then inserting an emoji (e.g. via Windows + <dot>, which opens an emoji
picker on recent Windows versions): Instead of showing an emoji, this
shows the infamous question mark in a black triangle, i.e. the invalid
Unicode character.
Let's special-case surrogate pairs in this scenario.
This fixes https://github.com/git-for-windows/git/issues/3281
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
i. e., Vista/2008.
AllocConsole appears to allow creating a console only on the currently
visible desktop since Windows 7, which broke the simple code opening
the console on an invisible desktop in an invisible window station.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Rather than fetching the system Windows directory at dll init time
only on 32 bit, fetch it on all platforms. Store as WCHAR and
UNICODE_STRING. Use where appropriate to simplify code.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
- Perhaps current code misunderstand meaning of the IGNBRK. As far
as I investigated, IGNBRK is concerned with break signal in serial
port but there is no evidence that it has effect to ignore Ctrl-C.
This patch stops ignoring Ctrl-C by IGNBRK for non-cygwin apps.
- If ENABLE_LINE_INPUT is set, Ctrl-S is handled by Windows if the
OS is Windows 7. This conflicts with Ctrl-S handling in cygwin
console code. This patch unsets ENABLE_LINE_INPUT flag in cygwin
and set it when native app is executed.
- If ENABLE_VIRTUAL_TERMINAL_INPUT is not set, changing window height
does not generate WINDOW_BUFFER_SIZE_EVENT. This happens if console
is in the legacy mode. Therefore, with this patch, the windows size
is checked every time in cons_master_thread() if the cosole is in
the legacy mode.
- Currently, Ctrl-Z, Ctrl-\ and SIGWINCH does not work in console
if the process does not call read() or select(). This is because
these are processed in process_input_message() which is called
from read() or select(). This is a long standing issue of console.
Addresses:
https://cygwin.com/pipermail/cygwin/2020-May/244898.htmlhttps://cygwin.com/pipermail/cygwin/2021-February/247779.html
With this patch, new thread which handles only input signals is
introduced so that Crtl-Z, etc. work without calling read() or
select(). Ctrl-S and Ctrl-Q are also handled in this thread.
- Currently, console read() keeps reading after SIGWINCH is sent
even if SA_RESTART flag is not set. With this patch, read()
returns EINTR on SIGWINCH if SA_RESTART flag is not set.
The same problem for SIGQUIT and SIGTSTP has also been fixed.
- Currently, read() returns -1 with EINTR if the process is suspended
by Ctrl-Z and resumed by fg command, while pty continues to read.
For example, xxd command stops with error "Interrupted system call"
after Ctrl-Z and fg. This patch aligns the behaviour with pty (and
Linux).
- After the commit 72770148, script command exits occasionally with
the error "Bad file descriptor" if it is started in console on Win7
and non-cygwin process is executed. This patch fixes the issue.
- After commit 232fde0e, pty changes console code page when the first
non-cygwin app is executed. If pty is started in real console device,
pty changes the code page of root console. This causes very annoying
result because changing code page changes the font of command prompt
if console is in legacy mode. This patch avoids this by creating a
new invisible console for the first pty started in console device.
Takashi Yano
Mitchell Hentges
Johannes Schindelin
Corinna Vinschen
Ken Brown
Takashi Yano via Cygwin-patches