2 * ALSA sequencer Priority Queue
3 * Copyright (c) 1998-1999 by Frank van de Pol <fvdpol@coil.demon.nl>
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.
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.
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
22 #include <linux/time.h>
23 #include <linux/slab.h>
24 #include <sound/core.h>
25 #include "seq_timer.h"
26 #include "seq_prioq.h"
29 /* Implementation is a simple linked list for now...
31 This priority queue orders the events on timestamp. For events with an
32 equeal timestamp the queue behaves as a FIFO.
56 /* create new prioq (constructor) */
57 struct snd_seq_prioq *snd_seq_prioq_new(void)
59 struct snd_seq_prioq *f;
61 f = kzalloc(sizeof(*f), GFP_KERNEL);
63 snd_printd("oops: malloc failed for snd_seq_prioq_new()\n");
67 spin_lock_init(&f->lock);
75 /* delete prioq (destructor) */
76 void snd_seq_prioq_delete(struct snd_seq_prioq **fifo)
78 struct snd_seq_prioq *f = *fifo;
82 snd_printd("oops: snd_seq_prioq_delete() called with NULL prioq\n");
86 /* release resources...*/
87 /*....................*/
92 snd_seq_cell_free(snd_seq_prioq_cell_out(f, NULL));
101 /* compare timestamp between events */
102 /* return 1 if a >= b; 0 */
103 static inline int compare_timestamp(struct snd_seq_event *a,
104 struct snd_seq_event *b)
106 if ((a->flags & SNDRV_SEQ_TIME_STAMP_MASK) == SNDRV_SEQ_TIME_STAMP_TICK) {
108 return (snd_seq_compare_tick_time(&a->time.tick, &b->time.tick));
110 /* compare real time */
111 return (snd_seq_compare_real_time(&a->time.time, &b->time.time));
115 /* compare timestamp between events */
116 /* return negative if a < b;
120 static inline int compare_timestamp_rel(struct snd_seq_event *a,
121 struct snd_seq_event *b)
123 if ((a->flags & SNDRV_SEQ_TIME_STAMP_MASK) == SNDRV_SEQ_TIME_STAMP_TICK) {
125 if (a->time.tick > b->time.tick)
127 else if (a->time.tick == b->time.tick)
132 /* compare real time */
133 if (a->time.time.tv_sec > b->time.time.tv_sec)
135 else if (a->time.time.tv_sec == b->time.time.tv_sec) {
136 if (a->time.time.tv_nsec > b->time.time.tv_nsec)
138 else if (a->time.time.tv_nsec == b->time.time.tv_nsec)
147 /* enqueue cell to prioq */
148 int snd_seq_prioq_cell_in(struct snd_seq_prioq * f,
149 struct snd_seq_event_cell * cell)
151 struct snd_seq_event_cell *cur, *prev;
156 if (snd_BUG_ON(!f || !cell))
160 prior = (cell->event.flags & SNDRV_SEQ_PRIORITY_MASK);
162 spin_lock_irqsave(&f->lock, flags);
164 /* check if this element needs to inserted at the end (ie. ordered
165 data is inserted) This will be very likeley if a sequencer
166 application or midi file player is feeding us (sequential) data */
167 if (f->tail && !prior) {
168 if (compare_timestamp(&cell->event, &f->tail->event)) {
169 /* add new cell to tail of the fifo */
170 f->tail->next = cell;
174 spin_unlock_irqrestore(&f->lock, flags);
178 /* traverse list of elements to find the place where the new cell is
179 to be inserted... Note that this is a order n process ! */
181 prev = NULL; /* previous cell */
182 cur = f->head; /* cursor */
184 count = 10000; /* FIXME: enough big, isn't it? */
185 while (cur != NULL) {
186 /* compare timestamps */
187 int rel = compare_timestamp_rel(&cell->event, &cur->event);
189 /* new cell has earlier schedule time, */
191 else if (rel == 0 && prior)
192 /* equal schedule time and prior to others */
194 /* new cell has equal or larger schedule time, */
195 /* move cursor to next cell */
199 spin_unlock_irqrestore(&f->lock, flags);
200 snd_printk(KERN_ERR "cannot find a pointer.. infinite loop?\n");
205 /* insert it before cursor */
210 if (f->head == cur) /* this is the first cell, set head to it */
212 if (cur == NULL) /* reached end of the list */
215 spin_unlock_irqrestore(&f->lock, flags);
219 /* return 1 if the current time >= event timestamp */
220 static int event_is_ready(struct snd_seq_event *ev, void *current_time)
222 if ((ev->flags & SNDRV_SEQ_TIME_STAMP_MASK) == SNDRV_SEQ_TIME_STAMP_TICK)
223 return snd_seq_compare_tick_time(current_time, &ev->time.tick);
225 return snd_seq_compare_real_time(current_time, &ev->time.time);
228 /* dequeue cell from prioq */
229 struct snd_seq_event_cell *snd_seq_prioq_cell_out(struct snd_seq_prioq *f,
232 struct snd_seq_event_cell *cell;
236 snd_printd("oops: snd_seq_prioq_cell_in() called with NULL prioq\n");
239 spin_lock_irqsave(&f->lock, flags);
242 if (cell && current_time && !event_is_ready(&cell->event, current_time))
245 f->head = cell->next;
247 /* reset tail if this was the last element */
255 spin_unlock_irqrestore(&f->lock, flags);
259 /* return number of events available in prioq */
260 int snd_seq_prioq_avail(struct snd_seq_prioq * f)
263 snd_printd("oops: snd_seq_prioq_cell_in() called with NULL prioq\n");
270 static inline int prioq_match(struct snd_seq_event_cell *cell,
271 int client, int timestamp)
273 if (cell->event.source.client == client ||
274 cell->event.dest.client == client)
278 switch (cell->event.flags & SNDRV_SEQ_TIME_STAMP_MASK) {
279 case SNDRV_SEQ_TIME_STAMP_TICK:
280 if (cell->event.time.tick)
283 case SNDRV_SEQ_TIME_STAMP_REAL:
284 if (cell->event.time.time.tv_sec ||
285 cell->event.time.time.tv_nsec)
292 /* remove cells for left client */
293 void snd_seq_prioq_leave(struct snd_seq_prioq * f, int client, int timestamp)
295 register struct snd_seq_event_cell *cell, *next;
297 struct snd_seq_event_cell *prev = NULL;
298 struct snd_seq_event_cell *freefirst = NULL, *freeprev = NULL, *freenext;
300 /* collect all removed cells */
301 spin_lock_irqsave(&f->lock, flags);
305 if (prioq_match(cell, client, timestamp)) {
306 /* remove cell from prioq */
307 if (cell == f->head) {
308 f->head = cell->next;
310 prev->next = cell->next;
313 f->tail = cell->next;
315 /* add cell to free list */
317 if (freefirst == NULL) {
320 freeprev->next = cell;
325 printk(KERN_DEBUG "type = %i, source = %i, dest = %i, "
328 cell->event.source.client,
329 cell->event.dest.client,
336 spin_unlock_irqrestore(&f->lock, flags);
338 /* remove selected cells */
340 freenext = freefirst->next;
341 snd_seq_cell_free(freefirst);
342 freefirst = freenext;
346 static int prioq_remove_match(struct snd_seq_remove_events *info,
347 struct snd_seq_event *ev)
351 if (info->remove_mode & SNDRV_SEQ_REMOVE_DEST) {
352 if (ev->dest.client != info->dest.client ||
353 ev->dest.port != info->dest.port)
356 if (info->remove_mode & SNDRV_SEQ_REMOVE_DEST_CHANNEL) {
357 if (! snd_seq_ev_is_channel_type(ev))
359 /* data.note.channel and data.control.channel are identical */
360 if (ev->data.note.channel != info->channel)
363 if (info->remove_mode & SNDRV_SEQ_REMOVE_TIME_AFTER) {
364 if (info->remove_mode & SNDRV_SEQ_REMOVE_TIME_TICK)
365 res = snd_seq_compare_tick_time(&ev->time.tick, &info->time.tick);
367 res = snd_seq_compare_real_time(&ev->time.time, &info->time.time);
371 if (info->remove_mode & SNDRV_SEQ_REMOVE_TIME_BEFORE) {
372 if (info->remove_mode & SNDRV_SEQ_REMOVE_TIME_TICK)
373 res = snd_seq_compare_tick_time(&ev->time.tick, &info->time.tick);
375 res = snd_seq_compare_real_time(&ev->time.time, &info->time.time);
379 if (info->remove_mode & SNDRV_SEQ_REMOVE_EVENT_TYPE) {
380 if (ev->type != info->type)
383 if (info->remove_mode & SNDRV_SEQ_REMOVE_IGNORE_OFF) {
384 /* Do not remove off events */
386 case SNDRV_SEQ_EVENT_NOTEOFF:
387 /* case SNDRV_SEQ_EVENT_SAMPLE_STOP: */
393 if (info->remove_mode & SNDRV_SEQ_REMOVE_TAG_MATCH) {
394 if (info->tag != ev->tag)
401 /* remove cells matching remove criteria */
402 void snd_seq_prioq_remove_events(struct snd_seq_prioq * f, int client,
403 struct snd_seq_remove_events *info)
405 struct snd_seq_event_cell *cell, *next;
407 struct snd_seq_event_cell *prev = NULL;
408 struct snd_seq_event_cell *freefirst = NULL, *freeprev = NULL, *freenext;
410 /* collect all removed cells */
411 spin_lock_irqsave(&f->lock, flags);
416 if (cell->event.source.client == client &&
417 prioq_remove_match(info, &cell->event)) {
419 /* remove cell from prioq */
420 if (cell == f->head) {
421 f->head = cell->next;
423 prev->next = cell->next;
427 f->tail = cell->next;
430 /* add cell to free list */
432 if (freefirst == NULL) {
435 freeprev->next = cell;
444 spin_unlock_irqrestore(&f->lock, flags);
446 /* remove selected cells */
448 freenext = freefirst->next;
449 snd_seq_cell_free(freefirst);
450 freefirst = freenext;