#include <sys/stat.h>
#include "vlc_block.h"
-/*****************************************************************************
- * Block functions.
- *****************************************************************************/
-/* private */
+/**
+ * @section Block handling functions.
+ */
+
+/**
+ * Internal state for heap block.
+ */
struct block_sys_t
{
block_t self;
return block;
}
-/*****************************************************************************
- * block_fifo_t management
- *****************************************************************************/
+/**
+ * @section Thread-safe block queue functions
+ */
+
+/**
+ * Internal state for block queues
+ */
struct block_fifo_t
{
vlc_mutex_t lock; /* fifo data lock */
- vlc_cond_t wait; /* fifo data conditional variable */
+ vlc_cond_t wait; /**< Wait for data */
+ vlc_cond_t wait_room; /**< Wait for queue depth to shrink */
block_t *p_first;
block_t **pp_last;
vlc_mutex_init( &p_fifo->lock );
vlc_cond_init( &p_fifo->wait );
+ vlc_cond_init( &p_fifo->wait_room );
p_fifo->p_first = NULL;
p_fifo->pp_last = &p_fifo->p_first;
p_fifo->i_depth = p_fifo->i_size = 0;
void block_FifoRelease( block_fifo_t *p_fifo )
{
block_FifoEmpty( p_fifo );
+ vlc_cond_destroy( &p_fifo->wait_room );
vlc_cond_destroy( &p_fifo->wait );
vlc_mutex_destroy( &p_fifo->lock );
free( p_fifo );
p_fifo->i_depth = p_fifo->i_size = 0;
p_fifo->p_first = NULL;
p_fifo->pp_last = &p_fifo->p_first;
+ vlc_cond_broadcast( &p_fifo->wait_room );
vlc_mutex_unlock( &p_fifo->lock );
}
+/**
+ * Wait until the FIFO gets below a certain size (if needed).
+ *
+ * Note that if more than one thread writes to the FIFO, you cannot assume that
+ * the FIFO is actually below the requested size upon return (since another
+ * thread could have refilled it already). This is typically not an issue, as
+ * this function is meant for (relaxed) congestion control.
+ *
+ * This function may be a cancellation point and it is cancel-safe.
+ *
+ * @param fifo queue to wait on
+ * @param max_depth wait until the queue has no more than this many blocks
+ * (use SIZE_MAX to ignore this constraint)
+ * @param max_size wait until the queue has no more than this many bytes
+ * (use SIZE_MAX to ignore this constraint)
+ * @return nothing.
+ */
+void block_FifoPace (block_fifo_t *fifo, size_t max_depth, size_t max_size)
+{
+ vlc_mutex_lock (&fifo->lock);
+ while ((fifo->i_depth > max_depth) || (fifo->i_size > max_size))
+ {
+ mutex_cleanup_push (&fifo->lock);
+ vlc_cond_wait (&fifo->wait_room, &fifo->lock);
+ vlc_cleanup_pop ();
+ }
+ vlc_mutex_unlock (&fifo->lock);
+}
+
/**
* Immediately queue one block at the end of a FIFO.
* @param fifo queue
p_fifo->pp_last = &p_fifo->p_first;
}
+ /* We don't know how many threads can queue new packets now. */
+ vlc_cond_broadcast( &p_fifo->wait_room );
vlc_mutex_unlock( &p_fifo->lock );
b->p_next = NULL;