diff options
Diffstat (limited to 'sound/core/seq/seq_fifo.h')
-rw-r--r-- | sound/core/seq/seq_fifo.h | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/sound/core/seq/seq_fifo.h b/sound/core/seq/seq_fifo.h new file mode 100644 index 000000000..5d38a0d7f --- /dev/null +++ b/sound/core/seq/seq_fifo.h @@ -0,0 +1,74 @@ +/* + * 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 |