Fix sigwait and pthread_kill return values in case of error

* signal.cc (sigwait): Fix return value to reflect errno in case of
	error according to POSIX.  Never return EINTR.
	* thread.cc (pthread_kill): Return errno if sig_send failed.

Signed-off-by: Corinna Vinschen <corinna@vinschen.de>

winsup/cygwin/ChangeLog

@@ -1,3 +1,9 @@
+2015-10-30  Corinna Vinschen  <corinna@vinschen.de>
+
+	* signal.cc (sigwait): Fix return value to reflect errno in case of
+	error according to POSIX.  Never return EINTR.
+	* thread.cc (pthread_kill): Return errno if sig_send failed.
+
 2015-10-29  Qian Hong  <qhong@codeweavers.com>
 
 	* init.cc (munge_threadfunc): Check that we're actually replacing

winsup/cygwin/release/2.3.0

@@ -53,3 +53,7 @@ Bug Fixes
 
 - Fix a potential SEGV on (at least) Wine.
   Addresses: https://cygwin.com/ml/cygwin/2015-10/msg00018.html
+
+- Fix sigwait(3) to return errno instead of -1 and never to return with EINTR.
+
+- Fix pthread_kill(3) to return errno instead of -1.

winsup/cygwin/signal.cc

@@ -557,10 +557,16 @@ siginterrupt (int sig, int flag)
 extern "C" int
 sigwait (const sigset_t *set, int *sig_ptr)
 {
-  int sig = sigwaitinfo (set, NULL);
+  int sig;
+
+  do
+    {
+      sig = sigwaitinfo (set, NULL);
+    }
+  while (sig == -1 && get_errno () == EINTR);
   if (sig > 0)
     *sig_ptr = sig;
-  return sig > 0 ? 0 : -1;
+  return sig > 0 ? 0 : get_errno ();
 }
 
 extern "C" int

winsup/cygwin/thread.cc

@@ -3056,7 +3056,11 @@ pthread_kill (pthread_t thread, int sig)
   if (!thread->valid)
     rval = ESRCH;
   else if (sig)
-    rval = sig_send (NULL, si, thread->cygtls);
+    {
+      rval = sig_send (NULL, si, thread->cygtls);
+      if (rval == -1)
+	rval = get_errno ();
+    }
   else
     switch (WaitForSingleObject (thread->win32_obj_id, 0))
       {