access: oss.c: exit while-loop on error and end of p_demux objects lifetime.

Check vlc_object_alive( p_demux ) && !p_demux->b_error in while loop.

modules/access/oss.c

@@ -298,23 +298,27 @@ static int DemuxControl( demux_t *p_demux, int i_query, va_list args )
 static int Demux( demux_t *p_demux )
 {
     demux_sys_t *p_sys = p_demux->p_sys;
-    block_t *p_block;
 
     do {
-        p_block = NULL;
         if( block_FifoCount( p_sys->p_grab->p_fifo ) > 0 )
         {
+            block_t *p_block;
+            mtime_t i_pts;
+
             p_block = block_FifoGet( p_sys->p_grab->p_fifo );
-            if( p_block )
+            if( !p_block )
+                break;
+
+            i_pts = p_block->i_pts;
             es_out_Send( p_demux->out, p_sys->p_es, p_block );
 
             if( p_sys->i_next_demux_date <= 0 &&
-                p_block->i_pts >= p_sys->i_next_demux_date )
-                goto out;
+                i_pts >= p_sys->i_next_demux_date )
+                break;
         }
-    } while( p_block );
+        else break;
+    } while( vlc_object_alive(p_demux) || !p_demux->b_error );
 
-out:
     return 1;
 }