1/*
2 *   ALSA sequencer FIFO
3 *   Copyright (c) 1998 by Frank van de Pol <fvdpol@coil.demon.nl>
4 *
5 *
6 *   This program is free software; you can redistribute it and/or modify
7 *   it under the terms of the GNU General Public License as published by
8 *   the Free Software Foundation; either version 2 of the License, or
9 *   (at your option) any later version.
10 *
11 *   This program is distributed in the hope that it will be useful,
12 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
13 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14 *   GNU General Public License for more details.
15 *
16 *   You should have received a copy of the GNU General Public License
17 *   along with this program; if not, write to the Free Software
18 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
19 *
20 */
21#ifndef __SND_SEQ_FIFO_H
22#define __SND_SEQ_FIFO_H
23
24#include "seq_memory.h"
25#include "seq_lock.h"
26
27
28/* === FIFO === */
29
30struct snd_seq_fifo {
31	struct snd_seq_pool *pool;		/* FIFO pool */
32	struct snd_seq_event_cell *head;    	/* pointer to head of fifo */
33	struct snd_seq_event_cell *tail;    	/* pointer to tail of fifo */
34	int cells;
35	spinlock_t lock;
36	snd_use_lock_t use_lock;
37	wait_queue_head_t input_sleep;
38	atomic_t overflow;
39
40};
41
42/* create new fifo (constructor) */
43struct snd_seq_fifo *snd_seq_fifo_new(int poolsize);
44
45/* delete fifo (destructor) */
46void snd_seq_fifo_delete(struct snd_seq_fifo **f);
47
48
49/* enqueue event to fifo */
50int snd_seq_fifo_event_in(struct snd_seq_fifo *f, struct snd_seq_event *event);
51
52/* lock fifo from release */
53#define snd_seq_fifo_lock(fifo)		snd_use_lock_use(&(fifo)->use_lock)
54#define snd_seq_fifo_unlock(fifo)	snd_use_lock_free(&(fifo)->use_lock)
55
56/* get a cell from fifo - fifo should be locked */
57int snd_seq_fifo_cell_out(struct snd_seq_fifo *f, struct snd_seq_event_cell **cellp, int nonblock);
58
59/* free dequeued cell - fifo should be locked */
60void snd_seq_fifo_cell_putback(struct snd_seq_fifo *f, struct snd_seq_event_cell *cell);
61
62/* clean up queue */
63void snd_seq_fifo_clear(struct snd_seq_fifo *f);
64
65/* polling */
66int snd_seq_fifo_poll_wait(struct snd_seq_fifo *f, struct file *file, poll_table *wait);
67
68/* resize pool in fifo */
69int snd_seq_fifo_resize(struct snd_seq_fifo *f, int poolsize);
70
71
72#endif
73