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/*
* ALSA sequencer FIFO
* Copyright (c) 1998 by Frank van de Pol <fvdpol@coil.demon.nl>
*
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#ifndef __SND_SEQ_FIFO_H
#define __SND_SEQ_FIFO_H
#include "seq_memory.h"
#include "seq_lock.h"
/* === FIFO === */
struct snd_seq_fifo {
struct snd_seq_pool *pool; /* FIFO pool */
struct snd_seq_event_cell *head; /* pointer to head of fifo */
struct snd_seq_event_cell *tail; /* pointer to tail of fifo */
int cells;
spinlock_t lock;
snd_use_lock_t use_lock;
wait_queue_head_t input_sleep;
atomic_t overflow;
};
/* create new fifo (constructor) */
struct snd_seq_fifo *snd_seq_fifo_new(int poolsize);
/* delete fifo (destructor) */
void snd_seq_fifo_delete(struct snd_seq_fifo **f);
/* enqueue event to fifo */
int snd_seq_fifo_event_in(struct snd_seq_fifo *f, struct snd_seq_event *event);
/* lock fifo from release */
#define snd_seq_fifo_lock(fifo) snd_use_lock_use(&(fifo)->use_lock)
#define snd_seq_fifo_unlock(fifo) snd_use_lock_free(&(fifo)->use_lock)
/* get a cell from fifo - fifo should be locked */
int snd_seq_fifo_cell_out(struct snd_seq_fifo *f, struct snd_seq_event_cell **cellp, int nonblock);
/* free dequeued cell - fifo should be locked */
void snd_seq_fifo_cell_putback(struct snd_seq_fifo *f, struct snd_seq_event_cell *cell);
/* clean up queue */
void snd_seq_fifo_clear(struct snd_seq_fifo *f);
/* polling */
int snd_seq_fifo_poll_wait(struct snd_seq_fifo *f, struct file *file, poll_table *wait);
/* resize pool in fifo */
int snd_seq_fifo_resize(struct snd_seq_fifo *f, int poolsize);
/* get the number of unused cells safely */
int snd_seq_fifo_unused_cells(struct snd_seq_fifo *f);
#endif
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