+ /* Locks : please note that if you need several of these locks, it is
+ * mandatory (to avoid deadlocks) to take them in the following order :
+ * mixer_lock, p_input->lock, output_fifo_lock, input_fifos_lock.
+ * --Meuuh */
+ /* When input_fifos_lock is taken, none of the p_input->fifo structures
+ * can be read or modified by a third-party thread. */
+ vlc_mutex_t input_fifos_lock;
+ /* When mixer_lock is taken, all decoder threads willing to mix a
+ * buffer must wait until it is released. The output pipeline cannot
+ * be modified. No input stream can be added or removed. */
+ vlc_mutex_t mixer_lock;
+ /* When output_fifo_lock is taken, the p_aout->output.fifo structure
+ * cannot be read or written by a third-party thread. */
+ vlc_mutex_t output_fifo_lock;
+