Cygwin: signal: Do not handle signal when __SIGFLUSHFAST is sent

The commit a22a0ad was not entirely correct. Even with the patch, some hangs still occur. This patch overrides the previous commit along with the patch that makes cygwait() reentrant, to fix these hangs. Addresses: https://cygwin.com/pipermail/cygwin/2024-December/256954.html Fixes: d243e51 ("Cygwin: signal: Fix deadlock between main thread and sig thread") Reported-by: Daisuke Fujimura <[email protected]> Reviewed-by: Corinna Vinschen <[email protected]> Signed-off-by: Takashi Yano <[email protected]> (cherry picked from commit 83afe3e)
msys2 · Jan 21, 2025 · adb9c01 · adb9c01
1 parent 9f9cfe9
commit adb9c01
Showing 1 changed file with 5 additions and 6 deletions.
diff --git a/winsup/cygwin/sigproc.cc b/winsup/cygwin/sigproc.cc
@@ -742,6 +742,9 @@ sig_send (_pinfo *p, siginfo_t& si, _cygtls *tls)
       memcpy (p, si._si_commune._si_str, n); p += n;
     }
 
+  unsigned cw_mask;
+  cw_mask = pack.si.si_signo == __SIGFLUSHFAST ? 0 : cw_sig_restart;
+
   DWORD nb;
   BOOL res;
   /* Try multiple times to send if packsize != nb since that probably
@@ -751,8 +754,7 @@ sig_send (_pinfo *p, siginfo_t& si, _cygtls *tls)
       res = WriteFile (sendsig, leader, packsize, &nb, NULL);
       if (!res || packsize == nb)
 	break;
-      if (cygwait (NULL, 10, cw_sig_eintr) == WAIT_SIGNALED)
-	_my_tls.call_signal_handler ();
+      cygwait (NULL, 10, cw_mask);
       res = 0;
     }
 
@@ -785,7 +787,7 @@ sig_send (_pinfo *p, siginfo_t& si, _cygtls *tls)
   if (wait_for_completion)
     {
       sigproc_printf ("Waiting for pack.wakeup %p", pack.wakeup);
-      rc = cygwait (pack.wakeup, WSSC);
+      rc = cygwait (pack.wakeup, WSSC, cw_mask);
       ForceCloseHandle (pack.wakeup);
     }
   else
@@ -806,9 +808,6 @@ sig_send (_pinfo *p, siginfo_t& si, _cygtls *tls)
       rc = -1;
     }
 
-  if (wait_for_completion && si.si_signo != __SIGFLUSHFAST)
-    _my_tls.call_signal_handler ();
-
 out:
   if (communing && rc)
     {