pulseaudio/src/memblockq.h

#ifndef foomemblockqhfoo
#define foomemblockqhfoo

#include <sys/types.h>

#include "memblock.h"
#include "memchunk.h"

struct pa_memblockq;

/* Parameters: the maximum length of the memblock queue, a base value
for all operations (that is, all byte operations shall work on
multiples of this base value) and an amount of bytes to prebuffer
before having pa_memblockq_peek() succeed. */
struct pa_memblockq* pa_memblockq_new(size_t maxlength, size_t base, size_t prebuf);
void pa_memblockq_free(struct pa_memblockq*bq);

/* Push a new memory chunk into the queue. Optionally specify a value for future cancellation. This is currently not implemented, however! */
void pa_memblockq_push(struct pa_memblockq* bq, const struct pa_memchunk *chunk, size_t delta);

/* Same as pa_memblockq_push(), however chunks are filtered through a mcalign object, and thus aligned to multiples of base */
void pa_memblockq_push_align(struct pa_memblockq* bq, const struct pa_memchunk *chunk, size_t delta);

/* Return a copy of the next memory chunk in the queue. It is not removed from the queue */
int pa_memblockq_peek(struct pa_memblockq* bq, struct pa_memchunk *chunk);

/* Drop the specified bytes from the queue */
void pa_memblockq_drop(struct pa_memblockq *bq, size_t length);

/* Shorten the pa_memblockq to the specified length by dropping data at the end of the queue */
void pa_memblockq_shorten(struct pa_memblockq *bq, size_t length);

/* Empty the pa_memblockq */
void pa_memblockq_empty(struct pa_memblockq *bq);

/* Test if the pa_memblockq is currently readable, that is, more data than base */
int pa_memblockq_is_readable(struct pa_memblockq *bq);

/* Test if the pa_memblockq is currently writable for the specified amount of bytes */
int pa_memblockq_is_writable(struct pa_memblockq *bq, size_t length);

/* The time memory chunks stay in the queue until they are removed completely in usecs */
uint32_t pa_memblockq_get_delay(struct pa_memblockq *bq);

/* Return the length of the queue in bytes */
uint32_t pa_memblockq_get_length(struct pa_memblockq *bq);

/* Return how many bytes are missing in queue to the specified fill amount */
uint32_t pa_memblockq_missing_to(struct pa_memblockq *bq, size_t qlen);

#endif