Am 02.08.2023 um 00:35 schrieb Takashi Yano: > On Tue, 1 Aug 2023 23:05:18 +0200 > Thomas Wolff wrote: >> I had reported this to the the main cygwin list: >> >> Am 20.07.2023 um 08:33 schrieb Thomas Wolff via Cygwin: >>> There was a report that on switching terminal windows with the mouse, >>> focus event reports (as enabled with ESC[?1004h) would sometimes get >>> mangled. >>> This is further described in issue reports to mintty/wsltty >>> (https://github.com/mintty/wsltty/issues/335) and also to tmux >>> (https://github.com/tmux/tmux/issues/3601). >>> >>> I could reproduce the issue without either of tmux or WSL. However, it >>> happens only once in a few hundred instances: >>> The escape sequence is changed so that the initial ESC is replaced by >>> one of the two subsequent characters, so instead of ESC[O, either of >>> [[O or sometimes O[O would be sent to the foreground application. >>> >>> I traced the issue down to the pty that connects mintty and its client >>> application, verified that the correct sequence is passed into write() >>> at the pty and the mangled sequence appears at read() in the client >>> process. In addition to a minimised test program that behaves like >>> `cat -v`, I also also put the test output directly into the client >>> process within the mintty code. >>> This leaves the only conclusion that the issue must be happening >>> somehow within pty handling, maybe in the context of some timing >>> condition or Windows messages being passed to mintty. >>> Anyhow, I was about to prepare testing with older mintty versions, in >>> case I overlooked something, when the OP reported that the issue does >>> not happen with cygwin 3.2.0. >>> Is there any recent change that could possibly cause such weird >>> behaviour? >>> Thomas >>> >> I have now automated the test case to chase the issue and associate it >> with a cygwin version. As unlikely as it may appear, results suggest >> that there is a case within the pty handling that may change sequences >> sent through it once in a while, more likely on a system under heavy load. >> I took some of the latest cygwin snapshots (by the way, there are no >> newer ones on the snapshots page): >> I can reproduce the issue with >>     3.3.5-341.x86_64.snap 2022-02-17 11:53 UTC >> while it did not occur with >>     3.4.0-341.x86_64.snap 2022-01-27 14:34 UTC >> Weird enough, the failing newer one is a cygwin 3.3.5 although the older >> one is a 3.4.0 version. > Can you provide the automated test case? I would like to > investigate what is happning. Manual test case: 1. Run `mintty echokey1` with the attached test program that runs like `cat -v` and detects the glitch 2. Run a second test window, same setup to increase the hit rate 3. Switch these 2 windows by clicking them in change a few hundred times, until the test program outputs "FAIL" Automated test case: 1. Use the tool TinyTask (https://www.tinytask.net/) to save the clicking. Sorry, I didn't manage to replace this with a self-made click simulator. 2. Place the 2 test windows in a specific position (e.g. covering the two screen halves in a top position) 3. Use the Record function of the tool and click to switch windows a dozen times, stop recording 4. Save the sequence as a TinyTask script, or use mine (2w.rec attached), better: load the script (Open), then create a standalone test executable (button "exe") to create tinytask2w.exe (I can send that to you if you like) 5. Optionally, create some background load on your system 6. Minimize other windows in case the test script does not hit the test windows 7. Run the test script minptytest (attached) to start the 2 windows and run the TinyTask standalone test in a loop; the script detects a marker file created by the test program; it also detect premature termination of a window (e.g. by hitting ^D in it) > >> Checking the git log around that time, there are a number of changes >> related to pty as listed below. I added some ! or ? marks to indicate >> more or less likely commits to be a culprit of this issue, judged on >> commit messages and browsing of code changes. >> >> I would also try to identify a commit more precisely but unfortunately >> the cygwin build process seems broken for me as it does not create the >> dll anymore... >> >> Thomas >> >> >> commit 2f2b91550547001b005393097c5a4328451343d6 >> Author: Takashi Yano >> Date:   Thu Feb 24 00:57:37 2022 +0900 >> >>     Cygwin: pty, console: Add a workaround for GDB SIGINT handling. >> >>     - 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. >> >> commit 2cab4d0bb4af5ad7ec97914068d5fa1b8954909c >> Author: Takashi Yano >> Date:   Tue Feb 15 23:23:50 2022 +0900 >> ? >>     Cygwin: pty, console: Refactor the code processing special keys. >> >>     - 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. >> >> commit bed1add783a13b3304b1625b962707f89e90e323 >> Author: Takashi Yano >> Date:   Sun Feb 13 05:12:18 2022 +0900 >> >>     Cygwin: pty: Fix a bug in tty_min::segpgid(). >> >>     - In tty_min::setpgid(), a pointer to fhandler instance is casted to >>       fhandler_pty_slave and accessed even if terminal is not a pty slave. >>       This patch fixes the issue. >> >> commit c4704c7c204e377859f657a3b06c112133adff09 >> Author: Takashi Yano >> Date:   Sun Feb 13 02:16:32 2022 +0900 >> >>     Cygwin: pty: Discard input in from_master_nat pipe on signal as well. >> >>     - Currently, pty discards input only in from_master pipe on signal. >>       Due to this, if pty is started without pseudo console support and >>       start a non-cygwin process from cmd.exe, type adhead input is not >>       discarded on signals such as Ctrl-C. This patch fixes the issue. >> >> commit b958e1f03acd1732bb0a433a589efb645458aac4 >> Author: Takashi Yano >> Date:   Thu Feb 10 17:47:51 2022 +0900 >> ? >>     Cygwin: pty: Revise the code to wait for completion of forwarding. >> >>     - With this patch, the code to wait for completion of forwarding of >>       output from non-cygwin app is revised so that it can more reliably >>       detect the completion. >> >> commit bddd9c1c417e97791c44241cf94753e90464501c >> Author: Takashi Yano >> Date:   Thu Feb 10 17:22:11 2022 +0900 >> !? >>     Cygwin: pty: Prevent deadlock on echo output. >> >>     - If the slave process writes a lot of text output, doecho() can >>       cause deadlock. This is because output_mutex is held in slave:: >>       write() and if WriteFile() is blocked due to pipe full, doecho() >>       tries to acquire output_mutex and gets into deadlock. With this >> !      patch, the deadlock is prevented on the sacrifice of atomicity >>       of doecho(). >> >> commit b04aea00f1bb503dcc364c83ee3ef3da3bc1305e >> Author: Takashi Yano >> Date:   Sat Feb 12 17:51:55 2022 +0900 >> ?? >>     Cygwin: pty: Pass Ctrl-Z (EOF) to non-cygwin apps with disable_pcon. >> >>     - Previously, non-cygwin app running in pty started without pseudo >>       console support was suspended by Ctrl-Z rather than sending EOF. >>       Even worse, suspended app could not be resumed by fg command. With >>       this patch, Ctrl-Z (EOF for non-cygwin apps) is passed to non-cygwin >>       app instead of suspending that app. This patch also handles Ctrl-\ >>       (QUIT) and Ctrl-D (EOF) as well. >> >> commit c05c36a7c8af5e97fa379abb7571ed35a0088e98 >> Author: Takashi Yano >> Date:   Thu Feb 10 16:53:47 2022 +0900 >> ?? >>     Cygwin: pty, console: Fix Ctrl-C handling for non-cygwin apps. >> >>     - 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. >> >> commit 909ed837ccb932ea70f71cc41891fa2c8143133f >> Author: Takashi Yano >> Date:   Fri Jan 14 19:35:12 2022 +0900 >> ?? >>     Cygwin: pty: Fix race issue between closing and opening master. >> >>     - If the from_master is closed before cleaning up other pipes, such >>       as from_slave_nat, the same pty may be allocated and pty master may >>       try to open the pipe which is not closed yet, and it will fail. >>       This patch fixes the issue. >> >> commit 3af461092e7ee9b76f3a1c18a6d95ed6e226df81 >> Author: Takashi Yano >> Date:   Thu Jan 13 19:44:43 2022 +0900 >> !? >>     Cygwin: pty: Stop closing and recreating attach_mutex. >> >>     - 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 >> >> commit 4f490c4cef8fd527642dbb5ea5373b373193a49b >> Author: Takashi Yano >> Date:   Thu Jan 13 18:18:00 2022 +0900 >> >>     Cygwin: pty: Fix memory leak in master_fwd_thread. >> >>     - If master_fwd_thread is terminated by cygthread::terminate_thread(), >>       the opportunity to release tmp_pathbuf is missed, resulting in a >>       memory leak. This patch fixes the issue. >> >> commit aa49985245e4e5b278778b0a47f6ce83cceb4ad4 >> Author: Takashi Yano >> Date:   Thu Jan 13 18:16:31 2022 +0900 >> ? >>     Cygwin: pty, console: Fix deadlock in GDB regarding mutex. >> >>     - 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 >> >> >