[newlib-cygwin] Cygwin: exceptions.cc: Suspend all threads in sig_handle_tty_stop().

[Corinna Vinschen]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=6c1552b0da7c7cdf1cf1668b3706c0d1a14c9b2d

commit 6c1552b0da7c7cdf1cf1668b3706c0d1a14c9b2d
Author: Takashi Yano via Cygwin-patches <cygwin-patches@cygwin.com>
Date:   Fri Jan 29 12:46:26 2021 +0900

    Cygwin: exceptions.cc: Suspend all threads in sig_handle_tty_stop().
    
    - Currently, thread created by pthread_create() is not suspended by
      the signal SIGTSTP. For example, even if a process with a thread
      is suspended by Ctrl-Z, the thread continues running. This patch
      fixes the issue.

Diff:
---
 winsup/cygwin/exceptions.cc | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/winsup/cygwin/exceptions.cc b/winsup/cygwin/exceptions.cc
index c98b92d30..3a6823325 100644
--- a/winsup/cygwin/exceptions.cc
+++ b/winsup/cygwin/exceptions.cc
@@ -902,7 +902,9 @@ sig_handle_tty_stop (int sig, siginfo_t *, void *)
 	 thread. */
       /* Use special cygwait parameter to handle SIGCONT.  _main_tls.sig will
 	 be cleared under lock when SIGCONT is detected.  */
+      pthread::suspend_all_except_self ();
       DWORD res = cygwait (NULL, cw_infinite, cw_sig_cont);
+      pthread::resume_all ();
       switch (res)
 	{
 	case WAIT_SIGNALED: