Handle EINTR from sigwait

(cherry picked from commit 5878fd30)

modules/control/signals.c

@@ -24,6 +24,7 @@
 
 #include <signal.h>
 #include <time.h>
+#include <assert.h>
 
 #include <vlc_common.h>
 #include <vlc_plugin.h>
@@ -100,8 +101,15 @@ static void *SigThread (void *data)
 
     do
     {
-        sigwait (&set, &signum);
-
+        switch (sigwait (&set, &signum))
+        {
+            case EINTR:
+                continue;
+            case 0:
+                break;
+            default:
+                assert (0);
+        }
 #ifdef __APPLE__
         /* In Mac OS X up to 10.5 sigwait (among others) is not a pthread
          * cancellation point */