stream: make stream_read_line() terminate line on EOF

Make sure we return an "empty" line on eof, to make sure we get
no buffer overflows in case some code fails to check the return value.

git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@31999 b3059339-0415-0410-9bf9-f77b7e298cf2

stream/stream.c

@@ -620,7 +620,7 @@ unsigned char* stream_read_line(stream_t *s,unsigned char* mem, int max, int utf
     }
     s->buf_pos += len;
   } while(!end);
-  if(s->eof && ptr == mem) return NULL;
   ptr[0] = 0;
+  if(s->eof && ptr == mem) return NULL;
   return mem;
 }