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v5.4
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *   ALSA sequencer Priority Queue
  4 *   Copyright (c) 1998-1999 by Frank van de Pol <fvdpol@coil.demon.nl>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  5 */
  6
  7#include <linux/time.h>
  8#include <linux/slab.h>
  9#include <sound/core.h>
 10#include "seq_timer.h"
 11#include "seq_prioq.h"
 12
 13
 14/* Implementation is a simple linked list for now...
 15
 16   This priority queue orders the events on timestamp. For events with an
 17   equeal timestamp the queue behaves as a FIFO. 
 18
 19   *
 20   *           +-------+
 21   *  Head --> | first |
 22   *           +-------+
 23   *                 |next
 24   *           +-----v-+
 25   *           |       |
 26   *           +-------+
 27   *                 |
 28   *           +-----v-+
 29   *           |       |
 30   *           +-------+
 31   *                 |
 32   *           +-----v-+
 33   *  Tail --> | last  |
 34   *           +-------+
 35   *
 36
 37 */
 38
 39
 40
 41/* create new prioq (constructor) */
 42struct snd_seq_prioq *snd_seq_prioq_new(void)
 43{
 44	struct snd_seq_prioq *f;
 45
 46	f = kzalloc(sizeof(*f), GFP_KERNEL);
 47	if (!f)
 48		return NULL;
 49	
 50	spin_lock_init(&f->lock);
 51	f->head = NULL;
 52	f->tail = NULL;
 53	f->cells = 0;
 54	
 55	return f;
 56}
 57
 58/* delete prioq (destructor) */
 59void snd_seq_prioq_delete(struct snd_seq_prioq **fifo)
 60{
 61	struct snd_seq_prioq *f = *fifo;
 62	*fifo = NULL;
 63
 64	if (f == NULL) {
 65		pr_debug("ALSA: seq: snd_seq_prioq_delete() called with NULL prioq\n");
 66		return;
 67	}
 68
 69	/* release resources...*/
 70	/*....................*/
 71	
 72	if (f->cells > 0) {
 73		/* drain prioQ */
 74		while (f->cells > 0)
 75			snd_seq_cell_free(snd_seq_prioq_cell_out(f, NULL));
 76	}
 77	
 78	kfree(f);
 79}
 80
 81
 82
 83
 84/* compare timestamp between events */
 85/* return 1 if a >= b; 0 */
 86static inline int compare_timestamp(struct snd_seq_event *a,
 87				    struct snd_seq_event *b)
 88{
 89	if ((a->flags & SNDRV_SEQ_TIME_STAMP_MASK) == SNDRV_SEQ_TIME_STAMP_TICK) {
 90		/* compare ticks */
 91		return (snd_seq_compare_tick_time(&a->time.tick, &b->time.tick));
 92	} else {
 93		/* compare real time */
 94		return (snd_seq_compare_real_time(&a->time.time, &b->time.time));
 95	}
 96}
 97
 98/* compare timestamp between events */
 99/* return negative if a < b;
100 *        zero     if a = b;
101 *        positive if a > b;
102 */
103static inline int compare_timestamp_rel(struct snd_seq_event *a,
104					struct snd_seq_event *b)
105{
106	if ((a->flags & SNDRV_SEQ_TIME_STAMP_MASK) == SNDRV_SEQ_TIME_STAMP_TICK) {
107		/* compare ticks */
108		if (a->time.tick > b->time.tick)
109			return 1;
110		else if (a->time.tick == b->time.tick)
111			return 0;
112		else
113			return -1;
114	} else {
115		/* compare real time */
116		if (a->time.time.tv_sec > b->time.time.tv_sec)
117			return 1;
118		else if (a->time.time.tv_sec == b->time.time.tv_sec) {
119			if (a->time.time.tv_nsec > b->time.time.tv_nsec)
120				return 1;
121			else if (a->time.time.tv_nsec == b->time.time.tv_nsec)
122				return 0;
123			else
124				return -1;
125		} else
126			return -1;
127	}
128}
129
130/* enqueue cell to prioq */
131int snd_seq_prioq_cell_in(struct snd_seq_prioq * f,
132			  struct snd_seq_event_cell * cell)
133{
134	struct snd_seq_event_cell *cur, *prev;
135	unsigned long flags;
136	int count;
137	int prior;
138
139	if (snd_BUG_ON(!f || !cell))
140		return -EINVAL;
141	
142	/* check flags */
143	prior = (cell->event.flags & SNDRV_SEQ_PRIORITY_MASK);
144
145	spin_lock_irqsave(&f->lock, flags);
146
147	/* check if this element needs to inserted at the end (ie. ordered 
148	   data is inserted) This will be very likeley if a sequencer 
149	   application or midi file player is feeding us (sequential) data */
150	if (f->tail && !prior) {
151		if (compare_timestamp(&cell->event, &f->tail->event)) {
152			/* add new cell to tail of the fifo */
153			f->tail->next = cell;
154			f->tail = cell;
155			cell->next = NULL;
156			f->cells++;
157			spin_unlock_irqrestore(&f->lock, flags);
158			return 0;
159		}
160	}
161	/* traverse list of elements to find the place where the new cell is
162	   to be inserted... Note that this is a order n process ! */
163
164	prev = NULL;		/* previous cell */
165	cur = f->head;		/* cursor */
166
167	count = 10000; /* FIXME: enough big, isn't it? */
168	while (cur != NULL) {
169		/* compare timestamps */
170		int rel = compare_timestamp_rel(&cell->event, &cur->event);
171		if (rel < 0)
172			/* new cell has earlier schedule time, */
173			break;
174		else if (rel == 0 && prior)
175			/* equal schedule time and prior to others */
176			break;
177		/* new cell has equal or larger schedule time, */
178		/* move cursor to next cell */
179		prev = cur;
180		cur = cur->next;
181		if (! --count) {
182			spin_unlock_irqrestore(&f->lock, flags);
183			pr_err("ALSA: seq: cannot find a pointer.. infinite loop?\n");
184			return -EINVAL;
185		}
186	}
187
188	/* insert it before cursor */
189	if (prev != NULL)
190		prev->next = cell;
191	cell->next = cur;
192
193	if (f->head == cur) /* this is the first cell, set head to it */
194		f->head = cell;
195	if (cur == NULL) /* reached end of the list */
196		f->tail = cell;
197	f->cells++;
198	spin_unlock_irqrestore(&f->lock, flags);
199	return 0;
200}
201
202/* return 1 if the current time >= event timestamp */
203static int event_is_ready(struct snd_seq_event *ev, void *current_time)
204{
205	if ((ev->flags & SNDRV_SEQ_TIME_STAMP_MASK) == SNDRV_SEQ_TIME_STAMP_TICK)
206		return snd_seq_compare_tick_time(current_time, &ev->time.tick);
207	else
208		return snd_seq_compare_real_time(current_time, &ev->time.time);
209}
210
211/* dequeue cell from prioq */
212struct snd_seq_event_cell *snd_seq_prioq_cell_out(struct snd_seq_prioq *f,
213						  void *current_time)
214{
215	struct snd_seq_event_cell *cell;
216	unsigned long flags;
217
218	if (f == NULL) {
219		pr_debug("ALSA: seq: snd_seq_prioq_cell_in() called with NULL prioq\n");
220		return NULL;
221	}
222	spin_lock_irqsave(&f->lock, flags);
223
224	cell = f->head;
225	if (cell && current_time && !event_is_ready(&cell->event, current_time))
226		cell = NULL;
227	if (cell) {
228		f->head = cell->next;
229
230		/* reset tail if this was the last element */
231		if (f->tail == cell)
232			f->tail = NULL;
233
234		cell->next = NULL;
235		f->cells--;
236	}
237
238	spin_unlock_irqrestore(&f->lock, flags);
239	return cell;
240}
241
242/* return number of events available in prioq */
243int snd_seq_prioq_avail(struct snd_seq_prioq * f)
244{
245	if (f == NULL) {
246		pr_debug("ALSA: seq: snd_seq_prioq_cell_in() called with NULL prioq\n");
247		return 0;
248	}
249	return f->cells;
250}
 
 
 
 
 
 
 
 
 
 
 
 
251
252static inline int prioq_match(struct snd_seq_event_cell *cell,
253			      int client, int timestamp)
254{
255	if (cell->event.source.client == client ||
256	    cell->event.dest.client == client)
257		return 1;
258	if (!timestamp)
259		return 0;
260	switch (cell->event.flags & SNDRV_SEQ_TIME_STAMP_MASK) {
261	case SNDRV_SEQ_TIME_STAMP_TICK:
262		if (cell->event.time.tick)
263			return 1;
264		break;
265	case SNDRV_SEQ_TIME_STAMP_REAL:
266		if (cell->event.time.time.tv_sec ||
267		    cell->event.time.time.tv_nsec)
268			return 1;
269		break;
270	}
271	return 0;
272}
273
274/* remove cells for left client */
275void snd_seq_prioq_leave(struct snd_seq_prioq * f, int client, int timestamp)
276{
277	register struct snd_seq_event_cell *cell, *next;
278	unsigned long flags;
279	struct snd_seq_event_cell *prev = NULL;
280	struct snd_seq_event_cell *freefirst = NULL, *freeprev = NULL, *freenext;
281
282	/* collect all removed cells */
283	spin_lock_irqsave(&f->lock, flags);
284	cell = f->head;
285	while (cell) {
286		next = cell->next;
287		if (prioq_match(cell, client, timestamp)) {
288			/* remove cell from prioq */
289			if (cell == f->head) {
290				f->head = cell->next;
291			} else {
292				prev->next = cell->next;
293			}
294			if (cell == f->tail)
295				f->tail = cell->next;
296			f->cells--;
297			/* add cell to free list */
298			cell->next = NULL;
299			if (freefirst == NULL) {
300				freefirst = cell;
301			} else {
302				freeprev->next = cell;
303			}
304			freeprev = cell;
305		} else {
306#if 0
307			pr_debug("ALSA: seq: type = %i, source = %i, dest = %i, "
308			       "client = %i\n",
309				cell->event.type,
310				cell->event.source.client,
311				cell->event.dest.client,
312				client);
313#endif
314			prev = cell;
315		}
316		cell = next;		
317	}
318	spin_unlock_irqrestore(&f->lock, flags);	
319
320	/* remove selected cells */
321	while (freefirst) {
322		freenext = freefirst->next;
323		snd_seq_cell_free(freefirst);
324		freefirst = freenext;
325	}
326}
327
328static int prioq_remove_match(struct snd_seq_remove_events *info,
329			      struct snd_seq_event *ev)
330{
331	int res;
332
333	if (info->remove_mode & SNDRV_SEQ_REMOVE_DEST) {
334		if (ev->dest.client != info->dest.client ||
335				ev->dest.port != info->dest.port)
336			return 0;
337	}
338	if (info->remove_mode & SNDRV_SEQ_REMOVE_DEST_CHANNEL) {
339		if (! snd_seq_ev_is_channel_type(ev))
340			return 0;
341		/* data.note.channel and data.control.channel are identical */
342		if (ev->data.note.channel != info->channel)
343			return 0;
344	}
345	if (info->remove_mode & SNDRV_SEQ_REMOVE_TIME_AFTER) {
346		if (info->remove_mode & SNDRV_SEQ_REMOVE_TIME_TICK)
347			res = snd_seq_compare_tick_time(&ev->time.tick, &info->time.tick);
348		else
349			res = snd_seq_compare_real_time(&ev->time.time, &info->time.time);
350		if (!res)
351			return 0;
352	}
353	if (info->remove_mode & SNDRV_SEQ_REMOVE_TIME_BEFORE) {
354		if (info->remove_mode & SNDRV_SEQ_REMOVE_TIME_TICK)
355			res = snd_seq_compare_tick_time(&ev->time.tick, &info->time.tick);
356		else
357			res = snd_seq_compare_real_time(&ev->time.time, &info->time.time);
358		if (res)
359			return 0;
360	}
361	if (info->remove_mode & SNDRV_SEQ_REMOVE_EVENT_TYPE) {
362		if (ev->type != info->type)
363			return 0;
364	}
365	if (info->remove_mode & SNDRV_SEQ_REMOVE_IGNORE_OFF) {
366		/* Do not remove off events */
367		switch (ev->type) {
368		case SNDRV_SEQ_EVENT_NOTEOFF:
369		/* case SNDRV_SEQ_EVENT_SAMPLE_STOP: */
370			return 0;
371		default:
372			break;
373		}
374	}
375	if (info->remove_mode & SNDRV_SEQ_REMOVE_TAG_MATCH) {
376		if (info->tag != ev->tag)
377			return 0;
378	}
379
380	return 1;
381}
382
383/* remove cells matching remove criteria */
384void snd_seq_prioq_remove_events(struct snd_seq_prioq * f, int client,
385				 struct snd_seq_remove_events *info)
386{
387	struct snd_seq_event_cell *cell, *next;
388	unsigned long flags;
389	struct snd_seq_event_cell *prev = NULL;
390	struct snd_seq_event_cell *freefirst = NULL, *freeprev = NULL, *freenext;
391
392	/* collect all removed cells */
393	spin_lock_irqsave(&f->lock, flags);
394	cell = f->head;
395
396	while (cell) {
397		next = cell->next;
398		if (cell->event.source.client == client &&
399			prioq_remove_match(info, &cell->event)) {
400
401			/* remove cell from prioq */
402			if (cell == f->head) {
403				f->head = cell->next;
404			} else {
405				prev->next = cell->next;
406			}
407
408			if (cell == f->tail)
409				f->tail = cell->next;
410			f->cells--;
411
412			/* add cell to free list */
413			cell->next = NULL;
414			if (freefirst == NULL) {
415				freefirst = cell;
416			} else {
417				freeprev->next = cell;
418			}
419
420			freeprev = cell;
421		} else {
422			prev = cell;
423		}
424		cell = next;		
425	}
426	spin_unlock_irqrestore(&f->lock, flags);	
427
428	/* remove selected cells */
429	while (freefirst) {
430		freenext = freefirst->next;
431		snd_seq_cell_free(freefirst);
432		freefirst = freenext;
433	}
434}
435
436
v4.10.11
 
  1/*
  2 *   ALSA sequencer Priority Queue
  3 *   Copyright (c) 1998-1999 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
 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"
 27
 28
 29/* Implementation is a simple linked list for now...
 30
 31   This priority queue orders the events on timestamp. For events with an
 32   equeal timestamp the queue behaves as a FIFO. 
 33
 34   *
 35   *           +-------+
 36   *  Head --> | first |
 37   *           +-------+
 38   *                 |next
 39   *           +-----v-+
 40   *           |       |
 41   *           +-------+
 42   *                 |
 43   *           +-----v-+
 44   *           |       |
 45   *           +-------+
 46   *                 |
 47   *           +-----v-+
 48   *  Tail --> | last  |
 49   *           +-------+
 50   *
 51
 52 */
 53
 54
 55
 56/* create new prioq (constructor) */
 57struct snd_seq_prioq *snd_seq_prioq_new(void)
 58{
 59	struct snd_seq_prioq *f;
 60
 61	f = kzalloc(sizeof(*f), GFP_KERNEL);
 62	if (!f)
 63		return NULL;
 64	
 65	spin_lock_init(&f->lock);
 66	f->head = NULL;
 67	f->tail = NULL;
 68	f->cells = 0;
 69	
 70	return f;
 71}
 72
 73/* delete prioq (destructor) */
 74void snd_seq_prioq_delete(struct snd_seq_prioq **fifo)
 75{
 76	struct snd_seq_prioq *f = *fifo;
 77	*fifo = NULL;
 78
 79	if (f == NULL) {
 80		pr_debug("ALSA: seq: snd_seq_prioq_delete() called with NULL prioq\n");
 81		return;
 82	}
 83
 84	/* release resources...*/
 85	/*....................*/
 86	
 87	if (f->cells > 0) {
 88		/* drain prioQ */
 89		while (f->cells > 0)
 90			snd_seq_cell_free(snd_seq_prioq_cell_out(f));
 91	}
 92	
 93	kfree(f);
 94}
 95
 96
 97
 98
 99/* compare timestamp between events */
100/* return 1 if a >= b; 0 */
101static inline int compare_timestamp(struct snd_seq_event *a,
102				    struct snd_seq_event *b)
103{
104	if ((a->flags & SNDRV_SEQ_TIME_STAMP_MASK) == SNDRV_SEQ_TIME_STAMP_TICK) {
105		/* compare ticks */
106		return (snd_seq_compare_tick_time(&a->time.tick, &b->time.tick));
107	} else {
108		/* compare real time */
109		return (snd_seq_compare_real_time(&a->time.time, &b->time.time));
110	}
111}
112
113/* compare timestamp between events */
114/* return negative if a < b;
115 *        zero     if a = b;
116 *        positive if a > b;
117 */
118static inline int compare_timestamp_rel(struct snd_seq_event *a,
119					struct snd_seq_event *b)
120{
121	if ((a->flags & SNDRV_SEQ_TIME_STAMP_MASK) == SNDRV_SEQ_TIME_STAMP_TICK) {
122		/* compare ticks */
123		if (a->time.tick > b->time.tick)
124			return 1;
125		else if (a->time.tick == b->time.tick)
126			return 0;
127		else
128			return -1;
129	} else {
130		/* compare real time */
131		if (a->time.time.tv_sec > b->time.time.tv_sec)
132			return 1;
133		else if (a->time.time.tv_sec == b->time.time.tv_sec) {
134			if (a->time.time.tv_nsec > b->time.time.tv_nsec)
135				return 1;
136			else if (a->time.time.tv_nsec == b->time.time.tv_nsec)
137				return 0;
138			else
139				return -1;
140		} else
141			return -1;
142	}
143}
144
145/* enqueue cell to prioq */
146int snd_seq_prioq_cell_in(struct snd_seq_prioq * f,
147			  struct snd_seq_event_cell * cell)
148{
149	struct snd_seq_event_cell *cur, *prev;
150	unsigned long flags;
151	int count;
152	int prior;
153
154	if (snd_BUG_ON(!f || !cell))
155		return -EINVAL;
156	
157	/* check flags */
158	prior = (cell->event.flags & SNDRV_SEQ_PRIORITY_MASK);
159
160	spin_lock_irqsave(&f->lock, flags);
161
162	/* check if this element needs to inserted at the end (ie. ordered 
163	   data is inserted) This will be very likeley if a sequencer 
164	   application or midi file player is feeding us (sequential) data */
165	if (f->tail && !prior) {
166		if (compare_timestamp(&cell->event, &f->tail->event)) {
167			/* add new cell to tail of the fifo */
168			f->tail->next = cell;
169			f->tail = cell;
170			cell->next = NULL;
171			f->cells++;
172			spin_unlock_irqrestore(&f->lock, flags);
173			return 0;
174		}
175	}
176	/* traverse list of elements to find the place where the new cell is
177	   to be inserted... Note that this is a order n process ! */
178
179	prev = NULL;		/* previous cell */
180	cur = f->head;		/* cursor */
181
182	count = 10000; /* FIXME: enough big, isn't it? */
183	while (cur != NULL) {
184		/* compare timestamps */
185		int rel = compare_timestamp_rel(&cell->event, &cur->event);
186		if (rel < 0)
187			/* new cell has earlier schedule time, */
188			break;
189		else if (rel == 0 && prior)
190			/* equal schedule time and prior to others */
191			break;
192		/* new cell has equal or larger schedule time, */
193		/* move cursor to next cell */
194		prev = cur;
195		cur = cur->next;
196		if (! --count) {
197			spin_unlock_irqrestore(&f->lock, flags);
198			pr_err("ALSA: seq: cannot find a pointer.. infinite loop?\n");
199			return -EINVAL;
200		}
201	}
202
203	/* insert it before cursor */
204	if (prev != NULL)
205		prev->next = cell;
206	cell->next = cur;
207
208	if (f->head == cur) /* this is the first cell, set head to it */
209		f->head = cell;
210	if (cur == NULL) /* reached end of the list */
211		f->tail = cell;
212	f->cells++;
213	spin_unlock_irqrestore(&f->lock, flags);
214	return 0;
215}
216
 
 
 
 
 
 
 
 
 
217/* dequeue cell from prioq */
218struct snd_seq_event_cell *snd_seq_prioq_cell_out(struct snd_seq_prioq *f)
 
219{
220	struct snd_seq_event_cell *cell;
221	unsigned long flags;
222
223	if (f == NULL) {
224		pr_debug("ALSA: seq: snd_seq_prioq_cell_in() called with NULL prioq\n");
225		return NULL;
226	}
227	spin_lock_irqsave(&f->lock, flags);
228
229	cell = f->head;
 
 
230	if (cell) {
231		f->head = cell->next;
232
233		/* reset tail if this was the last element */
234		if (f->tail == cell)
235			f->tail = NULL;
236
237		cell->next = NULL;
238		f->cells--;
239	}
240
241	spin_unlock_irqrestore(&f->lock, flags);
242	return cell;
243}
244
245/* return number of events available in prioq */
246int snd_seq_prioq_avail(struct snd_seq_prioq * f)
247{
248	if (f == NULL) {
249		pr_debug("ALSA: seq: snd_seq_prioq_cell_in() called with NULL prioq\n");
250		return 0;
251	}
252	return f->cells;
253}
254
255
256/* peek at cell at the head of the prioq */
257struct snd_seq_event_cell *snd_seq_prioq_cell_peek(struct snd_seq_prioq * f)
258{
259	if (f == NULL) {
260		pr_debug("ALSA: seq: snd_seq_prioq_cell_in() called with NULL prioq\n");
261		return NULL;
262	}
263	return f->head;
264}
265
266
267static inline int prioq_match(struct snd_seq_event_cell *cell,
268			      int client, int timestamp)
269{
270	if (cell->event.source.client == client ||
271	    cell->event.dest.client == client)
272		return 1;
273	if (!timestamp)
274		return 0;
275	switch (cell->event.flags & SNDRV_SEQ_TIME_STAMP_MASK) {
276	case SNDRV_SEQ_TIME_STAMP_TICK:
277		if (cell->event.time.tick)
278			return 1;
279		break;
280	case SNDRV_SEQ_TIME_STAMP_REAL:
281		if (cell->event.time.time.tv_sec ||
282		    cell->event.time.time.tv_nsec)
283			return 1;
284		break;
285	}
286	return 0;
287}
288
289/* remove cells for left client */
290void snd_seq_prioq_leave(struct snd_seq_prioq * f, int client, int timestamp)
291{
292	register struct snd_seq_event_cell *cell, *next;
293	unsigned long flags;
294	struct snd_seq_event_cell *prev = NULL;
295	struct snd_seq_event_cell *freefirst = NULL, *freeprev = NULL, *freenext;
296
297	/* collect all removed cells */
298	spin_lock_irqsave(&f->lock, flags);
299	cell = f->head;
300	while (cell) {
301		next = cell->next;
302		if (prioq_match(cell, client, timestamp)) {
303			/* remove cell from prioq */
304			if (cell == f->head) {
305				f->head = cell->next;
306			} else {
307				prev->next = cell->next;
308			}
309			if (cell == f->tail)
310				f->tail = cell->next;
311			f->cells--;
312			/* add cell to free list */
313			cell->next = NULL;
314			if (freefirst == NULL) {
315				freefirst = cell;
316			} else {
317				freeprev->next = cell;
318			}
319			freeprev = cell;
320		} else {
321#if 0
322			pr_debug("ALSA: seq: type = %i, source = %i, dest = %i, "
323			       "client = %i\n",
324				cell->event.type,
325				cell->event.source.client,
326				cell->event.dest.client,
327				client);
328#endif
329			prev = cell;
330		}
331		cell = next;		
332	}
333	spin_unlock_irqrestore(&f->lock, flags);	
334
335	/* remove selected cells */
336	while (freefirst) {
337		freenext = freefirst->next;
338		snd_seq_cell_free(freefirst);
339		freefirst = freenext;
340	}
341}
342
343static int prioq_remove_match(struct snd_seq_remove_events *info,
344			      struct snd_seq_event *ev)
345{
346	int res;
347
348	if (info->remove_mode & SNDRV_SEQ_REMOVE_DEST) {
349		if (ev->dest.client != info->dest.client ||
350				ev->dest.port != info->dest.port)
351			return 0;
352	}
353	if (info->remove_mode & SNDRV_SEQ_REMOVE_DEST_CHANNEL) {
354		if (! snd_seq_ev_is_channel_type(ev))
355			return 0;
356		/* data.note.channel and data.control.channel are identical */
357		if (ev->data.note.channel != info->channel)
358			return 0;
359	}
360	if (info->remove_mode & SNDRV_SEQ_REMOVE_TIME_AFTER) {
361		if (info->remove_mode & SNDRV_SEQ_REMOVE_TIME_TICK)
362			res = snd_seq_compare_tick_time(&ev->time.tick, &info->time.tick);
363		else
364			res = snd_seq_compare_real_time(&ev->time.time, &info->time.time);
365		if (!res)
366			return 0;
367	}
368	if (info->remove_mode & SNDRV_SEQ_REMOVE_TIME_BEFORE) {
369		if (info->remove_mode & SNDRV_SEQ_REMOVE_TIME_TICK)
370			res = snd_seq_compare_tick_time(&ev->time.tick, &info->time.tick);
371		else
372			res = snd_seq_compare_real_time(&ev->time.time, &info->time.time);
373		if (res)
374			return 0;
375	}
376	if (info->remove_mode & SNDRV_SEQ_REMOVE_EVENT_TYPE) {
377		if (ev->type != info->type)
378			return 0;
379	}
380	if (info->remove_mode & SNDRV_SEQ_REMOVE_IGNORE_OFF) {
381		/* Do not remove off events */
382		switch (ev->type) {
383		case SNDRV_SEQ_EVENT_NOTEOFF:
384		/* case SNDRV_SEQ_EVENT_SAMPLE_STOP: */
385			return 0;
386		default:
387			break;
388		}
389	}
390	if (info->remove_mode & SNDRV_SEQ_REMOVE_TAG_MATCH) {
391		if (info->tag != ev->tag)
392			return 0;
393	}
394
395	return 1;
396}
397
398/* remove cells matching remove criteria */
399void snd_seq_prioq_remove_events(struct snd_seq_prioq * f, int client,
400				 struct snd_seq_remove_events *info)
401{
402	struct snd_seq_event_cell *cell, *next;
403	unsigned long flags;
404	struct snd_seq_event_cell *prev = NULL;
405	struct snd_seq_event_cell *freefirst = NULL, *freeprev = NULL, *freenext;
406
407	/* collect all removed cells */
408	spin_lock_irqsave(&f->lock, flags);
409	cell = f->head;
410
411	while (cell) {
412		next = cell->next;
413		if (cell->event.source.client == client &&
414			prioq_remove_match(info, &cell->event)) {
415
416			/* remove cell from prioq */
417			if (cell == f->head) {
418				f->head = cell->next;
419			} else {
420				prev->next = cell->next;
421			}
422
423			if (cell == f->tail)
424				f->tail = cell->next;
425			f->cells--;
426
427			/* add cell to free list */
428			cell->next = NULL;
429			if (freefirst == NULL) {
430				freefirst = cell;
431			} else {
432				freeprev->next = cell;
433			}
434
435			freeprev = cell;
436		} else {
437			prev = cell;
438		}
439		cell = next;		
440	}
441	spin_unlock_irqrestore(&f->lock, flags);	
442
443	/* remove selected cells */
444	while (freefirst) {
445		freenext = freefirst->next;
446		snd_seq_cell_free(freefirst);
447		freefirst = freenext;
448	}
449}
450
451