stream, demux_lavf: minor cleanup for stream size code

demux/demux_lavf.c

@@ -112,9 +112,7 @@ static int64_t mp_seek(void *opaque, int64_t pos, int whence)
     else if (whence == SEEK_SET)
         pos += stream->start_pos;
     else if (whence == AVSEEK_SIZE && stream->end_pos > 0) {
-        uint64_t size;
+        stream_update_size(stream);
-        if (stream_control(stream, STREAM_CTRL_GET_SIZE, &size) == STREAM_OK)
-            return size;
         return stream->end_pos - stream->start_pos;
     } else
         return -1;

stream/stream.c

@@ -476,6 +476,15 @@ int stream_control(stream_t *s, int cmd, void *arg){
   return s->control(s, cmd, arg);
 }
 
+void stream_update_size(stream_t *s)
+{
+    uint64_t size;
+    if (stream_control(s, STREAM_CTRL_GET_SIZE, &size) == STREAM_OK) {
+        if (size > s->end_pos)
+            s->end_pos = size;
+    }
+}
+
 stream_t* new_memory_stream(unsigned char* data,int len){
   stream_t *s;
 

stream/stream.h

@@ -349,6 +349,7 @@ struct bstr stream_read_complete(struct stream *s, void *talloc_ctx,
                                  int max_size, int padding_bytes);
 void stream_reset(stream_t *s);
 int stream_control(stream_t *s, int cmd, void *arg);
+void stream_update_size(stream_t *s);
 stream_t* new_stream(int fd,int type);
 void free_stream(stream_t *s);
 stream_t* new_memory_stream(unsigned char* data,int len);