Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame^] | 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 | |
| 30 | typedef struct { |
| 31 | pool_t *pool; /* FIFO pool */ |
| 32 | snd_seq_event_cell_t* head; /* pointer to head of fifo */ |
| 33 | snd_seq_event_cell_t* 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 | } fifo_t; |
| 41 | |
| 42 | /* create new fifo (constructor) */ |
| 43 | extern fifo_t *snd_seq_fifo_new(int poolsize); |
| 44 | |
| 45 | /* delete fifo (destructor) */ |
| 46 | extern void snd_seq_fifo_delete(fifo_t **f); |
| 47 | |
| 48 | |
| 49 | /* enqueue event to fifo */ |
| 50 | extern int snd_seq_fifo_event_in(fifo_t *f, snd_seq_event_t *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 */ |
| 57 | int snd_seq_fifo_cell_out(fifo_t *f, snd_seq_event_cell_t **cellp, int nonblock); |
| 58 | |
| 59 | /* free dequeued cell - fifo should be locked */ |
| 60 | extern void snd_seq_fifo_cell_putback(fifo_t *f, snd_seq_event_cell_t *cell); |
| 61 | |
| 62 | /* clean up queue */ |
| 63 | extern void snd_seq_fifo_clear(fifo_t *f); |
| 64 | |
| 65 | /* polling */ |
| 66 | extern int snd_seq_fifo_poll_wait(fifo_t *f, struct file *file, poll_table *wait); |
| 67 | |
| 68 | /* resize pool in fifo */ |
| 69 | int snd_seq_fifo_resize(fifo_t *f, int poolsize); |
| 70 | |
| 71 | |
| 72 | #endif |