Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 <sound/driver.h> |
| 23 | #include <linux/time.h> |
| 24 | #include <linux/slab.h> |
| 25 | #include <sound/core.h> |
| 26 | #include "seq_timer.h" |
| 27 | #include "seq_prioq.h" |
| 28 | |
| 29 | |
| 30 | /* Implementation is a simple linked list for now... |
| 31 | |
| 32 | This priority queue orders the events on timestamp. For events with an |
| 33 | equeal timestamp the queue behaves as a FIFO. |
| 34 | |
| 35 | * |
| 36 | * +-------+ |
| 37 | * Head --> | first | |
| 38 | * +-------+ |
| 39 | * |next |
| 40 | * +-----v-+ |
| 41 | * | | |
| 42 | * +-------+ |
| 43 | * | |
| 44 | * +-----v-+ |
| 45 | * | | |
| 46 | * +-------+ |
| 47 | * | |
| 48 | * +-----v-+ |
| 49 | * Tail --> | last | |
| 50 | * +-------+ |
| 51 | * |
| 52 | |
| 53 | */ |
| 54 | |
| 55 | |
| 56 | |
| 57 | /* create new prioq (constructor) */ |
| 58 | prioq_t *snd_seq_prioq_new(void) |
| 59 | { |
| 60 | prioq_t *f; |
| 61 | |
Takashi Iwai | ecca82b | 2005-09-09 14:20:49 +0200 | [diff] [blame] | 62 | f = kzalloc(sizeof(*f), GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 63 | if (f == NULL) { |
| 64 | snd_printd("oops: malloc failed for snd_seq_prioq_new()\n"); |
| 65 | return NULL; |
| 66 | } |
| 67 | |
| 68 | spin_lock_init(&f->lock); |
| 69 | f->head = NULL; |
| 70 | f->tail = NULL; |
| 71 | f->cells = 0; |
| 72 | |
| 73 | return f; |
| 74 | } |
| 75 | |
| 76 | /* delete prioq (destructor) */ |
| 77 | void snd_seq_prioq_delete(prioq_t **fifo) |
| 78 | { |
| 79 | prioq_t *f = *fifo; |
| 80 | *fifo = NULL; |
| 81 | |
| 82 | if (f == NULL) { |
| 83 | snd_printd("oops: snd_seq_prioq_delete() called with NULL prioq\n"); |
| 84 | return; |
| 85 | } |
| 86 | |
| 87 | /* release resources...*/ |
| 88 | /*....................*/ |
| 89 | |
| 90 | if (f->cells > 0) { |
| 91 | /* drain prioQ */ |
| 92 | while (f->cells > 0) |
| 93 | snd_seq_cell_free(snd_seq_prioq_cell_out(f)); |
| 94 | } |
| 95 | |
| 96 | kfree(f); |
| 97 | } |
| 98 | |
| 99 | |
| 100 | |
| 101 | |
| 102 | /* compare timestamp between events */ |
| 103 | /* return 1 if a >= b; 0 */ |
| 104 | static inline int compare_timestamp(snd_seq_event_t * a, snd_seq_event_t * b) |
| 105 | { |
| 106 | if ((a->flags & SNDRV_SEQ_TIME_STAMP_MASK) == SNDRV_SEQ_TIME_STAMP_TICK) { |
| 107 | /* compare ticks */ |
| 108 | return (snd_seq_compare_tick_time(&a->time.tick, &b->time.tick)); |
| 109 | } else { |
| 110 | /* compare real time */ |
| 111 | return (snd_seq_compare_real_time(&a->time.time, &b->time.time)); |
| 112 | } |
| 113 | } |
| 114 | |
| 115 | /* compare timestamp between events */ |
| 116 | /* return negative if a < b; |
| 117 | * zero if a = b; |
| 118 | * positive if a > b; |
| 119 | */ |
| 120 | static inline int compare_timestamp_rel(snd_seq_event_t *a, snd_seq_event_t *b) |
| 121 | { |
| 122 | if ((a->flags & SNDRV_SEQ_TIME_STAMP_MASK) == SNDRV_SEQ_TIME_STAMP_TICK) { |
| 123 | /* compare ticks */ |
| 124 | if (a->time.tick > b->time.tick) |
| 125 | return 1; |
| 126 | else if (a->time.tick == b->time.tick) |
| 127 | return 0; |
| 128 | else |
| 129 | return -1; |
| 130 | } else { |
| 131 | /* compare real time */ |
| 132 | if (a->time.time.tv_sec > b->time.time.tv_sec) |
| 133 | return 1; |
| 134 | else if (a->time.time.tv_sec == b->time.time.tv_sec) { |
| 135 | if (a->time.time.tv_nsec > b->time.time.tv_nsec) |
| 136 | return 1; |
| 137 | else if (a->time.time.tv_nsec == b->time.time.tv_nsec) |
| 138 | return 0; |
| 139 | else |
| 140 | return -1; |
| 141 | } else |
| 142 | return -1; |
| 143 | } |
| 144 | } |
| 145 | |
| 146 | /* enqueue cell to prioq */ |
| 147 | int snd_seq_prioq_cell_in(prioq_t * f, snd_seq_event_cell_t * cell) |
| 148 | { |
| 149 | snd_seq_event_cell_t *cur, *prev; |
| 150 | unsigned long flags; |
| 151 | int count; |
| 152 | int prior; |
| 153 | |
| 154 | snd_assert(f, return -EINVAL); |
| 155 | snd_assert(cell, 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 | snd_printk(KERN_ERR "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 */ |
| 218 | snd_seq_event_cell_t *snd_seq_prioq_cell_out(prioq_t * f) |
| 219 | { |
| 220 | snd_seq_event_cell_t *cell; |
| 221 | unsigned long flags; |
| 222 | |
| 223 | if (f == NULL) { |
| 224 | snd_printd("oops: 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 */ |
| 246 | int snd_seq_prioq_avail(prioq_t * f) |
| 247 | { |
| 248 | if (f == NULL) { |
| 249 | snd_printd("oops: 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 */ |
| 257 | snd_seq_event_cell_t *snd_seq_prioq_cell_peek(prioq_t * f) |
| 258 | { |
| 259 | if (f == NULL) { |
| 260 | snd_printd("oops: snd_seq_prioq_cell_in() called with NULL prioq\n"); |
| 261 | return NULL; |
| 262 | } |
| 263 | return f->head; |
| 264 | } |
| 265 | |
| 266 | |
| 267 | static inline int prioq_match(snd_seq_event_cell_t *cell, int client, int timestamp) |
| 268 | { |
| 269 | if (cell->event.source.client == client || |
| 270 | cell->event.dest.client == client) |
| 271 | return 1; |
| 272 | if (!timestamp) |
| 273 | return 0; |
| 274 | switch (cell->event.flags & SNDRV_SEQ_TIME_STAMP_MASK) { |
| 275 | case SNDRV_SEQ_TIME_STAMP_TICK: |
| 276 | if (cell->event.time.tick) |
| 277 | return 1; |
| 278 | break; |
| 279 | case SNDRV_SEQ_TIME_STAMP_REAL: |
| 280 | if (cell->event.time.time.tv_sec || |
| 281 | cell->event.time.time.tv_nsec) |
| 282 | return 1; |
| 283 | break; |
| 284 | } |
| 285 | return 0; |
| 286 | } |
| 287 | |
| 288 | /* remove cells for left client */ |
| 289 | void snd_seq_prioq_leave(prioq_t * f, int client, int timestamp) |
| 290 | { |
| 291 | register snd_seq_event_cell_t *cell, *next; |
| 292 | unsigned long flags; |
| 293 | snd_seq_event_cell_t *prev = NULL; |
| 294 | snd_seq_event_cell_t *freefirst = NULL, *freeprev = NULL, *freenext; |
| 295 | |
| 296 | /* collect all removed cells */ |
| 297 | spin_lock_irqsave(&f->lock, flags); |
| 298 | cell = f->head; |
| 299 | while (cell) { |
| 300 | next = cell->next; |
| 301 | if (prioq_match(cell, client, timestamp)) { |
| 302 | /* remove cell from prioq */ |
| 303 | if (cell == f->head) { |
| 304 | f->head = cell->next; |
| 305 | } else { |
| 306 | prev->next = cell->next; |
| 307 | } |
| 308 | if (cell == f->tail) |
| 309 | f->tail = cell->next; |
| 310 | f->cells--; |
| 311 | /* add cell to free list */ |
| 312 | cell->next = NULL; |
| 313 | if (freefirst == NULL) { |
| 314 | freefirst = cell; |
| 315 | } else { |
| 316 | freeprev->next = cell; |
| 317 | } |
| 318 | freeprev = cell; |
| 319 | } else { |
| 320 | #if 0 |
| 321 | printk("type = %i, source = %i, dest = %i, client = %i\n", |
| 322 | cell->event.type, |
| 323 | cell->event.source.client, |
| 324 | cell->event.dest.client, |
| 325 | client); |
| 326 | #endif |
| 327 | prev = cell; |
| 328 | } |
| 329 | cell = next; |
| 330 | } |
| 331 | spin_unlock_irqrestore(&f->lock, flags); |
| 332 | |
| 333 | /* remove selected cells */ |
| 334 | while (freefirst) { |
| 335 | freenext = freefirst->next; |
| 336 | snd_seq_cell_free(freefirst); |
| 337 | freefirst = freenext; |
| 338 | } |
| 339 | } |
| 340 | |
| 341 | static int prioq_remove_match(snd_seq_remove_events_t *info, |
| 342 | snd_seq_event_t *ev) |
| 343 | { |
| 344 | int res; |
| 345 | |
| 346 | if (info->remove_mode & SNDRV_SEQ_REMOVE_DEST) { |
| 347 | if (ev->dest.client != info->dest.client || |
| 348 | ev->dest.port != info->dest.port) |
| 349 | return 0; |
| 350 | } |
| 351 | if (info->remove_mode & SNDRV_SEQ_REMOVE_DEST_CHANNEL) { |
| 352 | if (! snd_seq_ev_is_channel_type(ev)) |
| 353 | return 0; |
| 354 | /* data.note.channel and data.control.channel are identical */ |
| 355 | if (ev->data.note.channel != info->channel) |
| 356 | return 0; |
| 357 | } |
| 358 | if (info->remove_mode & SNDRV_SEQ_REMOVE_TIME_AFTER) { |
| 359 | if (info->remove_mode & SNDRV_SEQ_REMOVE_TIME_TICK) |
| 360 | res = snd_seq_compare_tick_time(&ev->time.tick, &info->time.tick); |
| 361 | else |
| 362 | res = snd_seq_compare_real_time(&ev->time.time, &info->time.time); |
| 363 | if (!res) |
| 364 | return 0; |
| 365 | } |
| 366 | if (info->remove_mode & SNDRV_SEQ_REMOVE_TIME_BEFORE) { |
| 367 | if (info->remove_mode & SNDRV_SEQ_REMOVE_TIME_TICK) |
| 368 | res = snd_seq_compare_tick_time(&ev->time.tick, &info->time.tick); |
| 369 | else |
| 370 | res = snd_seq_compare_real_time(&ev->time.time, &info->time.time); |
| 371 | if (res) |
| 372 | return 0; |
| 373 | } |
| 374 | if (info->remove_mode & SNDRV_SEQ_REMOVE_EVENT_TYPE) { |
| 375 | if (ev->type != info->type) |
| 376 | return 0; |
| 377 | } |
| 378 | if (info->remove_mode & SNDRV_SEQ_REMOVE_IGNORE_OFF) { |
| 379 | /* Do not remove off events */ |
| 380 | switch (ev->type) { |
| 381 | case SNDRV_SEQ_EVENT_NOTEOFF: |
| 382 | /* case SNDRV_SEQ_EVENT_SAMPLE_STOP: */ |
| 383 | return 0; |
| 384 | default: |
| 385 | break; |
| 386 | } |
| 387 | } |
| 388 | if (info->remove_mode & SNDRV_SEQ_REMOVE_TAG_MATCH) { |
| 389 | if (info->tag != ev->tag) |
| 390 | return 0; |
| 391 | } |
| 392 | |
| 393 | return 1; |
| 394 | } |
| 395 | |
| 396 | /* remove cells matching remove criteria */ |
| 397 | void snd_seq_prioq_remove_events(prioq_t * f, int client, |
| 398 | snd_seq_remove_events_t *info) |
| 399 | { |
| 400 | register snd_seq_event_cell_t *cell, *next; |
| 401 | unsigned long flags; |
| 402 | snd_seq_event_cell_t *prev = NULL; |
| 403 | snd_seq_event_cell_t *freefirst = NULL, *freeprev = NULL, *freenext; |
| 404 | |
| 405 | /* collect all removed cells */ |
| 406 | spin_lock_irqsave(&f->lock, flags); |
| 407 | cell = f->head; |
| 408 | |
| 409 | while (cell) { |
| 410 | next = cell->next; |
| 411 | if (cell->event.source.client == client && |
| 412 | prioq_remove_match(info, &cell->event)) { |
| 413 | |
| 414 | /* remove cell from prioq */ |
| 415 | if (cell == f->head) { |
| 416 | f->head = cell->next; |
| 417 | } else { |
| 418 | prev->next = cell->next; |
| 419 | } |
| 420 | |
| 421 | if (cell == f->tail) |
| 422 | f->tail = cell->next; |
| 423 | f->cells--; |
| 424 | |
| 425 | /* add cell to free list */ |
| 426 | cell->next = NULL; |
| 427 | if (freefirst == NULL) { |
| 428 | freefirst = cell; |
| 429 | } else { |
| 430 | freeprev->next = cell; |
| 431 | } |
| 432 | |
| 433 | freeprev = cell; |
| 434 | } else { |
| 435 | prev = cell; |
| 436 | } |
| 437 | cell = next; |
| 438 | } |
| 439 | spin_unlock_irqrestore(&f->lock, flags); |
| 440 | |
| 441 | /* remove selected cells */ |
| 442 | while (freefirst) { |
| 443 | freenext = freefirst->next; |
| 444 | snd_seq_cell_free(freefirst); |
| 445 | freefirst = freenext; |
| 446 | } |
| 447 | } |
| 448 | |
| 449 | |