- In push_to_pcon_screenbuffer(), open() and ioctl() are called.
Since push_to_pcon_screenbuffer() is called in read() and write(),
errno which is set in read() and write() code may be overwritten
in open() or ioctl() call. This patch prevent this situation.
- PTY has a bug reported in:
https://cygwin.com/ml/cygwin/2020-02/msg00067.html.
This is the result of state mismatch between real pseudo console
attaching state and state variable. This patch fixes the issue.
- PTY has a problem that the key input, which is typed during
windows native app is running, disappear when it returns to shell.
(Problem 3 in https://cygwin.com/ml/cygwin/2020-02/msg00007.html)
This is beacuse pty has two input pipes, one is for cygwin apps
and the other one is for native windows apps. The key input during
windows native program is running is sent to the second input pipe
while cygwin shell reads input from the first input pipe.
This patch realize transfering input data between these two pipes.
- Debug codes used in the early stage of pseudo console support are
removed. (Regarding ALWAYS_USE_PCON and USE_API_HOOK) Along with
this, the codes related to this change are organized.
- PTY code has a problem that tcsh is terminated if the following
command is executed.
true; chcp &
This seems to be caused by invalid pointer access which occurs
when the process exits during the kill() code is execuetd. This
patch avoids the issue by not using kill().
- After commit 6cc299f0e2, outputs of
cygwin programs which call both printf() and WriteConsole() are
frequently distorted. This patch fixes the issue.
- The cause of the problem reported in
https://www.cygwin.com/ml/cygwin/2020-01/msg00220.html is that the
chars input before dup() cannot be read from the new file descriptor.
This is because the readahead buffer (rabuf) in the console is newly
created by dup(), and does not inherit from the parent. This patch
fixes the issue.
- For programs which does not work properly with pseudo console,
disable_pcon in environment CYGWIN is introduced. If disable_pcon
is set, pseudo console support is disabled.
- For programs compiled with -mwindows option, reopening slave is
needed in push_to_pcon_screenbuffer(), however, it was not at
appropriate place. This causes the problem reported in
https://www.cygwin.com/ml/cygwin/2020-01/msg00161.html. This
patch fixes the issue.
- Though this rarely happens, sometimes the first printing of non-
cygwin process does not displayed correctly. To fix this issue,
the code for waiting for forwarding by master_fwd_thread is revised.
- After commit e1a0775dc0, the problem
reported in https://www.cygwin.com/ml/cygwin/2020-01/msg00093.html
occurs. For Gnu scren and tmux, calling FreeConsole() on pty close
is necessary. However, if FreeConsole() is called, cygwin setup
with '-h' option does not work. Therefore, the commit
e1a0775dc0 delayed closing pty.
This is the cause of the problem above. Now, instead of delaying
pty close, FreeConsole() is not called if the process is non cygwin
processes such as cygwin setup.
- Special function keys such as arrow keys or function keys do not
work in ConEmu with cygwin-connector after commit
6a06c6bc8f. This patch fixes the
issue.
- PTY code which support pseudo console has a problem that causes
handle leaks. Four of these are bug in pty code, and the other
one seems to be a bug of Windows10. ClosePseudoConsole() fails
to close one internal handle. This patch fixes the issue.
- If two PTYs are opened in the same process and the first one
is closed, the helper process for the first PTY remains running.
This patch fixes the issue.
- Even with commit fe512b2b12, pty
still has a problem in ESC[?3h and ESC[?3l handling if invalid
sequence such as ESC[?$ is sent. This patch fixes the issue.
- Pseudo console clears console screen buffer if ESC[?3h or ESC[?3l
is sent. However, xterm/vt100 does not clear screen. This cause
mismatch between real screen and console screen buffer. Therefore,
this patch triggers redraw screen in that situation so that the
synchronization is done on the next execution of native app.
This solves the problem reported in:
https://www.cygwin.com/ml/cygwin-patches/2019-q4/msg00116.html
- Previously, pty cleared screen at startup for synchronization
between the real screen and console screen buffer for pseudo
console. With this patch, instead of clearing screen, the screen
is redrawn when the first native program is executed after pty
is created. In other words, synchronization is deferred until
the native app is executed. Moreover, this realizes excluding
$TERM dependent code.
- The autoload feature is used rather than GetModuleHandle(),
GetProcAddress() for CreatePseudoConsole(), ResizePseudoConsole()
and ClosePseudoConsole().
- Since calling system __loadlocale() caused execution error,
PTY used its own NLS function. The cause of the error has been
found, the corresponding code has been rewritten using system
function.
- Previously, input and output pipes were switched together between
the traditional pty and the pseudo console. However, for example,
if stdin is redirected to another device, it is better to leave
input pipe traditional pty side even for non-cygwin program. This
patch realizes such behaviour.
- If screen alternated while pseudo console switching, it sometimes
failed. This might happen when the output of the non-cygwin program
is piped to less. This patch fixes this issue.
- When the I/O pipe is switched to the pseudo console side, the
behaviour of Ctrl-C was unstable. This rarely happens, however,
for example, shell sometimes crashes by Ctrl-C in that situation.
Furthermore, Ctrl-C was ignored if output of non-cygwin program
is redirected to pipe. This patch fixes these issues.
- Forcibly attach to pseudo console in advance so that the error
messages by system_printf() are displayed to screen reliably.
This is needed when stdout is redirected to another pty. In this
case, process has two ptys opened. However, process can attach
to only one console. So it is necessary to change console attached.
- select() did not work correctly when both read and except are
polled simultaneously for the same fd and the r/w pipe is switched
to pseudo console side. This patch fixes this isseu.
- Pseudo console support introduced by commit
169d65a577 shows garbage ^[[H^[[J in
some of emacs screens. These screens do not handle ANSI escape
sequences. Therefore, clear screen is disabled on these screens.
- API hook used for pseudo console support causes slow down.
This patch limits API hook to only program which is linked
with the corresponding APIs. Normal cygwin program is not
linked with such APIs (such as WriteFile, etc...) directly,
therefore, no slow down occurs. However, console access by
cygwin.dll itself cannot switch the r/w pipe to pseudo console
side. Therefore, the code to switch it forcely to pseudo
console side is added to smallprint.cc and strace.cc.
Takashi Yano