newlib-cygwin/winsup
Takashi Yano c4fb5da278 Cygwin: pty: Avoid client deadlock when pty master stops to read.
Previsouly, the following commands hangs:
  mintty -e timeout 1 dash -c 'yes aaaaaaaaaaaaaaaaaaaaaaaaa | cat'

The mechanism is as follows.

When the child process (timeout) is terminated, mintty seems to stop
reading pty master even if yes or cat still alive.

If the the pipe used to transfer output from pty slave to pty master
is full due to lack of master reader, WriteFile() to the pipe is
blocked. WriteFile() cannot be canceled by cygwin signal, therefore,
pty slave hangs.

This patch avoids hanging by checking pipe space before calling
WriteFile() and prevents writing data more than space.

Addresses: https://cygwin.com/pipermail/cygwin/2024-June/256178.html
Reported-by: jojelino <jojelino@gmail.com>
Signed-off-by: Takashi Yano <takashi.yano@nifty.ne.jp>
2024-07-01 17:45:00 +09:00
..
CVSChangeLogs.old
cygserver Revert "sys/types.h: Don't include sys/_stdint.h" 2022-05-04 15:08:44 +02:00
cygwin Cygwin: pty: Avoid client deadlock when pty master stops to read. 2024-07-01 17:45:00 +09:00
doc Cygwin: FS_IOC_[GS]ETFLAGS: handle pinned and unpinned attributes 2024-03-08 21:54:58 +01:00
testsuite Cygwin: remove warnings from testsuite build 2024-01-19 15:11:32 +01:00
utils Cygwin: disable high-entropy VA for ldh 2024-06-03 05:31:18 +09:00
CONTRIBUTORS Cygwin: Add Ben Wijen to list of contributors 2021-01-18 12:01:19 +01:00
COPYING
COPYING.LIB
CYGWIN_LICENSE
Makefile.am Cygwin: Conditionally build documentation 2021-12-17 22:28:16 +00:00
Makefile.am.common Cygwin: automake: change @INCLUDES@ to @AM_CPPFLAGS@ to avoid warnings 2021-04-29 11:28:14 +02:00
README
acinclude.m4 Cygwin: Reorganize cygwin source dir 2022-08-05 12:02:11 +02:00
autogen.sh Cygwin: autogen.sh: Allow running from any directory 2021-05-06 10:56:20 +02:00
configure.ac Cygwin: testsuite: Drop using DejaGnu to run tests 2023-07-22 17:16:37 +01:00

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