From ef33379be8be59c475cdb280e2e2f414fe1c2a8e Mon Sep 17 00:00:00 2001
From: Christopher Faylor <me@cgf.cx>
Date: Mon, 26 Jan 2004 22:25:57 +0000
Subject: [PATCH] * exceptions.cc (sig_handle_tty_stop): Avoid races by waiting
 for both signal_arrived and for sigCONT. (sigpacket::process): Enforce
 sending of both signal_arrived and sigCONT, where appropriate. * gendef
 (sigreturn): Save tls pointer in ebx so that it can jump into sigdelayed and
 use the same register.

---
 winsup/cygwin/ChangeLog     |  9 +++++++++
 winsup/cygwin/exceptions.cc | 28 ++++++++++++++++++++++------
 winsup/cygwin/gendef        |  6 +++---
 3 files changed, 34 insertions(+), 9 deletions(-)

diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index bfc201968..fd17f338b 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,12 @@
+2004-01-26  Christopher Faylor  <cgf@redhat.com>
+
+	* exceptions.cc (sig_handle_tty_stop): Avoid races by waiting for both
+	signal_arrived and for sigCONT.
+	(sigpacket::process): Enforce sending of both signal_arrived and
+	sigCONT, where appropriate.
+	* gendef (sigreturn): Save tls pointer in ebx so that it can jump into
+	sigdelayed and use the same register.
+
 2004-01-26  Christopher Faylor  <cgf@redhat.com>
 
 	* cygtls.cc (_threadinfo::init_thread): Add more local reent stdio
diff --git a/winsup/cygwin/exceptions.cc b/winsup/cygwin/exceptions.cc
index db70fa51d..11088fcfd 100644
--- a/winsup/cygwin/exceptions.cc
+++ b/winsup/cygwin/exceptions.cc
@@ -644,8 +644,19 @@ sig_handle_tty_stop (int sig)
     }
   sigproc_printf ("process %d stopped by signal %d, myself->ppid_handle %p",
 		  myself->pid, sig, myself->ppid_handle);
-  if (WaitForSingleObject (sigCONT, INFINITE) != WAIT_OBJECT_0)
-    api_fatal ("WaitSingleObject failed, %E");
+  HANDLE w4[2];
+  w4[0] = sigCONT;
+  w4[1] = signal_arrived;
+  switch (WaitForMultipleObjects (2, w4, TRUE, INFINITE))
+    {
+    case WAIT_OBJECT_0:
+    case WAIT_OBJECT_0 + 1:
+      reset_signal_arrived ();
+      break;
+    default:
+      api_fatal ("WaitSingleObject failed, %E");
+      break;
+    }
   return;
 }
 }
@@ -925,9 +936,12 @@ set_signal_mask (sigset_t newmask, sigset_t oldmask)
 int __stdcall
 sigpacket::process ()
 {
-  if (si.si_signo == SIGCONT)
+  DWORD continue_now;
+  if (si.si_signo != SIGCONT)
+    continue_now = false;
+  else
     {
-      DWORD stopped = myself->process_state & PID_STOPPED;
+      continue_now = myself->process_state & PID_STOPPED;
       myself->stopsig = 0;
       myself->process_state &= ~PID_STOPPED;
       /* Clear pending stop signals */
@@ -935,8 +949,6 @@ sigpacket::process ()
       sig_clear (SIGTSTP);
       sig_clear (SIGTTIN);
       sig_clear (SIGTTOU);
-      if (stopped)
-	SetEvent (sigCONT);
     }
 
   int rc = 1;
@@ -1001,6 +1013,8 @@ sigpacket::process ()
 	  || si.si_signo == SIGURG)
 	{
 	  sigproc_printf ("default signal %d ignored", si.si_signo);
+	  if (continue_now)
+	    SetEvent (signal_arrived);
 	  goto done;
 	}
 
@@ -1037,6 +1051,8 @@ dosig1:
   rc = setup_handler (si.si_signo, handler, thissig, tls);
 
 done:
+  if (continue_now)
+    SetEvent (sigCONT);
   sigproc_printf ("returning %d", rc);
   return rc;
 
diff --git a/winsup/cygwin/gendef b/winsup/cygwin/gendef
index 5addf91e2..d317eeacd 100755
--- a/winsup/cygwin/gendef
+++ b/winsup/cygwin/gendef
@@ -127,15 +127,15 @@ _sigreturn:
 	addl	\$4,%esp			# Remove argument
 	call	_set_process_mask\@4
 
-	movl	%fs:4,%eax
+	movl	%fs:4,%ebx
 
-	cmpl	\$0,$tls::sig(%eax)	# Did a signal come in?
+	cmpl	\$0,$tls::sig(%ebx)	# Did a signal come in?
 	jnz	3f			# Yes, if non-zero
 
 1:	popl	%edx			# saved errno
 	testl	%edx,%edx		# Is it < 0
 	jl	2f			# yup.  ignore it
-	movl	$tls::errno_addr(%eax),%eax
+	movl	$tls::errno_addr(%ebx),%eax
 	movl	%edx,(%eax)
 2:	popl	%eax
 	popl	%ebx