code.delx.au - pulseaudio/blob - src/pulse/mainloop.c

   1 /* $Id$ */
   2
   3 /***
   4   This file is part of PulseAudio.
   5
   6   Copyright 2004-2006 Lennart Poettering
   7   Copyright 2006 Pierre Ossman <ossman@cendio.se> for Cendio AB
   8
   9   PulseAudio is free software; you can redistribute it and/or modify
  10   it under the terms of the GNU Lesser General Public License as published
  11   by the Free Software Foundation; either version 2 of the License,
  12   or (at your option) any later version.
  13
  14   PulseAudio is distributed in the hope that it will be useful, but
  15   WITHOUT ANY WARRANTY; without even the implied warranty of
  16   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  17   General Public License for more details.
  18
  19   You should have received a copy of the GNU Lesser General Public License
  20   along with PulseAudio; if not, write to the Free Software
  21   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  22   USA.
  23 ***/
  24
  25 #ifdef HAVE_CONFIG_H
  26 #include <config.h>
  27 #endif
  28
  29 #include <stdio.h>
  30 #include <signal.h>
  31 #include <unistd.h>
  32 #include <stdlib.h>
  33 #include <string.h>
  34 #include <assert.h>
  35 #include <fcntl.h>
  36 #include <errno.h>
  37
  38 #ifdef HAVE_SYS_POLL_H
  39 #include <sys/poll.h>
  40 #else
  41 #include "../pulsecore/poll.h"
  42 #endif
  43
  44 #include "../pulsecore/winsock.h"
  45
  46 #ifndef HAVE_PIPE
  47 #include "../pulsecore/pipe.h"
  48 #endif
  49
  50 #include <pulsecore/core-error.h>
  51 #include <pulse/timeval.h>
  52 #include <pulse/xmalloc.h>
  53
  54 #include <pulsecore/core-util.h>
  55 #include <pulsecore/llist.h>
  56 #include <pulsecore/log.h>
  57
  58 #include "mainloop.h"
  59
  60 struct pa_io_event {
  61     pa_mainloop *mainloop;
  62     int dead;
  63
  64     int fd;
  65     pa_io_event_flags_t events;
  66     struct pollfd *pollfd;
  67
  68     pa_io_event_cb_t callback;
  69     void *userdata;
  70     pa_io_event_destroy_cb_t destroy_callback;
  71
  72     PA_LLIST_FIELDS(pa_io_event);
  73 };
  74
  75 struct pa_time_event {
  76     pa_mainloop *mainloop;
  77     int dead;
  78
  79     int enabled;
  80     struct timeval timeval;
  81
  82     pa_time_event_cb_t callback;
  83     void *userdata;
  84     pa_time_event_destroy_cb_t destroy_callback;
  85
  86     PA_LLIST_FIELDS(pa_time_event);
  87 };
  88
  89 struct pa_defer_event {
  90     pa_mainloop *mainloop;
  91     int dead;
  92
  93     int enabled;
  94
  95     pa_defer_event_cb_t callback;
  96     void *userdata;
  97     pa_defer_event_destroy_cb_t destroy_callback;
  98
  99     PA_LLIST_FIELDS(pa_defer_event);
 100 };
 101
 102 struct pa_mainloop {
 103     PA_LLIST_HEAD(pa_io_event, io_events);
 104     PA_LLIST_HEAD(pa_time_event, time_events);
 105     PA_LLIST_HEAD(pa_defer_event, defer_events);
 106
 107     int n_enabled_defer_events, n_enabled_time_events, n_io_events;
 108     int io_events_please_scan, time_events_please_scan, defer_events_please_scan;
 109
 110     struct pollfd *pollfds;
 111     unsigned max_pollfds, n_pollfds;
 112     int rebuild_pollfds;
 113
 114     int prepared_timeout;
 115     pa_time_event *cached_next_time_event;
 116
 117     int quit, retval;
 118     pa_mainloop_api api;
 119
 120     int wakeup_pipe[2];
 121     int wakeup_pipe_type;
 122     int wakeup_requested;
 123
 124     enum {
 125         STATE_PASSIVE,
 126         STATE_PREPARED,
 127         STATE_POLLING,
 128         STATE_POLLED,
 129         STATE_QUIT
 130     } state;
 131
 132     pa_poll_func poll_func;
 133     void *poll_func_userdata;
 134     int poll_func_ret;
 135 };
 136
 137 static short map_flags_to_libc(pa_io_event_flags_t flags) {
 138     return
 139         (flags & PA_IO_EVENT_INPUT ? POLLIN : 0) |
 140         (flags & PA_IO_EVENT_OUTPUT ? POLLOUT : 0) |
 141         (flags & PA_IO_EVENT_ERROR ? POLLERR : 0) |
 142         (flags & PA_IO_EVENT_HANGUP ? POLLHUP : 0);
 143 }
 144
 145 static pa_io_event_flags_t map_flags_from_libc(short flags) {
 146     return
 147         (flags & POLLIN ? PA_IO_EVENT_INPUT : 0) |
 148         (flags & POLLOUT ? PA_IO_EVENT_OUTPUT : 0) |
 149         (flags & POLLERR ? PA_IO_EVENT_ERROR : 0) |
 150         (flags & POLLHUP ? PA_IO_EVENT_HANGUP : 0);
 151 }
 152
 153 /* IO events */
 154 static pa_io_event* mainloop_io_new(
 155         pa_mainloop_api*a,
 156         int fd,
 157         pa_io_event_flags_t events,
 158         pa_io_event_cb_t callback,
 159         void *userdata) {
 160
 161     pa_mainloop *m;
 162     pa_io_event *e;
 163
 164     assert(a);
 165     assert(a->userdata);
 166     assert(fd >= 0);
 167     assert(callback);
 168
 169     m = a->userdata;
 170     assert(a == &m->api);
 171
 172     e = pa_xnew(pa_io_event, 1);
 173     e->mainloop = m;
 174     e->dead = 0;
 175
 176     e->fd = fd;
 177     e->events = events;
 178     e->pollfd = NULL;
 179
 180     e->callback = callback;
 181     e->userdata = userdata;
 182     e->destroy_callback = NULL;
 183
 184 #ifdef OS_IS_WIN32
 185     {
 186         fd_set xset;
 187         struct timeval tv;
 188
 189         tv.tv_sec = 0;
 190         tv.tv_usec = 0;
 191
 192         FD_ZERO (&xset);
 193         FD_SET (fd, &xset);
 194
 195         if ((select((SELECT_TYPE_ARG1) fd, NULL, NULL, SELECT_TYPE_ARG234 &xset,
 196                     SELECT_TYPE_ARG5 &tv) == -1) &&
 197              (WSAGetLastError() == WSAENOTSOCK)) {
 198             pa_log_warn("WARNING: cannot monitor non-socket file descriptors.");
 199             e->dead = 1;
 200         }
 201     }
 202 #endif
 203
 204     PA_LLIST_PREPEND(pa_io_event, m->io_events, e);
 205     m->rebuild_pollfds = 1;
 206     m->n_io_events ++;
 207
 208     pa_mainloop_wakeup(m);
 209
 210     return e;
 211 }
 212
 213 static void mainloop_io_enable(pa_io_event *e, pa_io_event_flags_t events) {
 214     assert(e);
 215     assert(!e->dead);
 216
 217     if (e->events == events)
 218         return;
 219
 220     e->events = events;
 221
 222     if (e->pollfd)
 223         e->pollfd->events = map_flags_to_libc(events);
 224     else
 225         e->mainloop->rebuild_pollfds = 1;
 226
 227     pa_mainloop_wakeup(e->mainloop);
 228 }
 229
 230 static void mainloop_io_free(pa_io_event *e) {
 231     assert(e);
 232     assert(!e->dead);
 233
 234     e->dead = 1;
 235     e->mainloop->io_events_please_scan ++;
 236
 237     e->mainloop->n_io_events --;
 238     e->mainloop->rebuild_pollfds = 1;
 239
 240     pa_mainloop_wakeup(e->mainloop);
 241 }
 242
 243 static void mainloop_io_set_destroy(pa_io_event *e, pa_io_event_destroy_cb_t callback) {
 244     assert(e);
 245
 246     e->destroy_callback = callback;
 247 }
 248
 249 /* Defer events */
 250 static pa_defer_event* mainloop_defer_new(
 251         pa_mainloop_api*a,
 252         pa_defer_event_cb_t callback,
 253         void *userdata) {
 254
 255     pa_mainloop *m;
 256     pa_defer_event *e;
 257
 258     assert(a);
 259     assert(a->userdata);
 260     assert(callback);
 261
 262     m = a->userdata;
 263     assert(a == &m->api);
 264
 265     e = pa_xnew(pa_defer_event, 1);
 266     e->mainloop = m;
 267     e->dead = 0;
 268
 269     e->enabled = 1;
 270     m->n_enabled_defer_events++;
 271
 272     e->callback = callback;
 273     e->userdata = userdata;
 274     e->destroy_callback = NULL;
 275
 276     PA_LLIST_PREPEND(pa_defer_event, m->defer_events, e);
 277
 278     pa_mainloop_wakeup(e->mainloop);
 279
 280     return e;
 281 }
 282
 283 static void mainloop_defer_enable(pa_defer_event *e, int b) {
 284     assert(e);
 285     assert(!e->dead);
 286
 287     if (e->enabled && !b) {
 288         assert(e->mainloop->n_enabled_defer_events > 0);
 289         e->mainloop->n_enabled_defer_events--;
 290     } else if (!e->enabled && b) {
 291         e->mainloop->n_enabled_defer_events++;
 292         pa_mainloop_wakeup(e->mainloop);
 293     }
 294
 295     e->enabled = b;
 296 }
 297
 298 static void mainloop_defer_free(pa_defer_event *e) {
 299     assert(e);
 300     assert(!e->dead);
 301
 302     e->dead = 1;
 303     e->mainloop->defer_events_please_scan ++;
 304
 305     if (e->enabled) {
 306         assert(e->mainloop->n_enabled_defer_events > 0);
 307         e->mainloop->n_enabled_defer_events--;
 308     }
 309 }
 310
 311 static void mainloop_defer_set_destroy(pa_defer_event *e, pa_defer_event_destroy_cb_t callback) {
 312     assert(e);
 313     assert(!e->dead);
 314
 315     e->destroy_callback = callback;
 316 }
 317
 318 /* Time events */
 319 static pa_time_event* mainloop_time_new(
 320         pa_mainloop_api*a,
 321         const struct timeval *tv,
 322         pa_time_event_cb_t callback,
 323         void *userdata) {
 324
 325     pa_mainloop *m;
 326     pa_time_event *e;
 327
 328     assert(a);
 329     assert(a->userdata);
 330     assert(callback);
 331
 332     m = a->userdata;
 333     assert(a == &m->api);
 334
 335     e = pa_xnew(pa_time_event, 1);
 336     e->mainloop = m;
 337     e->dead = 0;
 338
 339     if ((e->enabled = !!tv)) {
 340         e->timeval = *tv;
 341
 342         m->n_enabled_time_events++;
 343
 344         if (m->cached_next_time_event) {
 345             assert(m->cached_next_time_event->enabled);
 346
 347             if (pa_timeval_cmp(tv, &m->cached_next_time_event->timeval) < 0)
 348                 m->cached_next_time_event = e;
 349         }
 350     }
 351
 352     e->callback = callback;
 353     e->userdata = userdata;
 354     e->destroy_callback = NULL;
 355
 356     PA_LLIST_PREPEND(pa_time_event, m->time_events, e);
 357
 358     if (e->enabled)
 359         pa_mainloop_wakeup(m);
 360
 361     return e;
 362 }
 363
 364 static void mainloop_time_restart(pa_time_event *e, const struct timeval *tv) {
 365     assert(e);
 366     assert(!e->dead);
 367
 368     if (e->enabled && !tv) {
 369         assert(e->mainloop->n_enabled_time_events > 0);
 370         e->mainloop->n_enabled_time_events--;
 371     } else if (!e->enabled && tv)
 372         e->mainloop->n_enabled_time_events++;
 373
 374     if ((e->enabled = !!tv)) {
 375         e->timeval = *tv;
 376         pa_mainloop_wakeup(e->mainloop);
 377     }
 378
 379     if (e->mainloop->cached_next_time_event && e->enabled) {
 380         assert(e->mainloop->cached_next_time_event->enabled);
 381
 382         if (pa_timeval_cmp(tv, &e->mainloop->cached_next_time_event->timeval) < 0)
 383             e->mainloop->cached_next_time_event = e;
 384     } else if (e->mainloop->cached_next_time_event == e)
 385         e->mainloop->cached_next_time_event = NULL;
 386 }
 387
 388 static void mainloop_time_free(pa_time_event *e) {
 389     assert(e);
 390     assert(!e->dead);
 391
 392     e->dead = 1;
 393     e->mainloop->time_events_please_scan ++;
 394
 395     if (e->enabled) {
 396         assert(e->mainloop->n_enabled_time_events > 0);
 397         e->mainloop->n_enabled_time_events--;
 398     }
 399
 400     if (e->mainloop->cached_next_time_event == e)
 401         e->mainloop->cached_next_time_event = NULL;
 402
 403     /* no wakeup needed here. Think about it! */
 404 }
 405
 406 static void mainloop_time_set_destroy(pa_time_event *e, pa_time_event_destroy_cb_t callback) {
 407     assert(e);
 408     assert(!e->dead);
 409
 410     e->destroy_callback = callback;
 411 }
 412
 413 /* quit() */
 414
 415 static void mainloop_quit(pa_mainloop_api*a, int retval) {
 416     pa_mainloop *m;
 417
 418     assert(a);
 419     assert(a->userdata);
 420     m = a->userdata;
 421     assert(a == &m->api);
 422
 423     pa_mainloop_quit(m, retval);
 424 }
 425
 426 static const pa_mainloop_api vtable = {
 427     .userdata = NULL,
 428
 429     .io_new= mainloop_io_new,
 430     .io_enable= mainloop_io_enable,
 431     .io_free= mainloop_io_free,
 432     .io_set_destroy= mainloop_io_set_destroy,
 433
 434     .time_new = mainloop_time_new,
 435     .time_restart = mainloop_time_restart,
 436     .time_free = mainloop_time_free,
 437     .time_set_destroy = mainloop_time_set_destroy,
 438
 439     .defer_new = mainloop_defer_new,
 440     .defer_enable = mainloop_defer_enable,
 441     .defer_free = mainloop_defer_free,
 442     .defer_set_destroy = mainloop_defer_set_destroy,
 443
 444     .quit = mainloop_quit,
 445 };
 446
 447 pa_mainloop *pa_mainloop_new(void) {
 448     pa_mainloop *m;
 449
 450     m = pa_xnew(pa_mainloop, 1);
 451
 452     m->wakeup_pipe_type = 0;
 453     if (pipe(m->wakeup_pipe) < 0) {
 454         pa_log_error("ERROR: cannot create wakeup pipe");
 455         pa_xfree(m);
 456         return NULL;
 457     }
 458
 459     pa_make_nonblock_fd(m->wakeup_pipe[0]);
 460     pa_make_nonblock_fd(m->wakeup_pipe[1]);
 461     m->wakeup_requested = 0;
 462
 463     PA_LLIST_HEAD_INIT(pa_io_event, m->io_events);
 464     PA_LLIST_HEAD_INIT(pa_time_event, m->time_events);
 465     PA_LLIST_HEAD_INIT(pa_defer_event, m->defer_events);
 466
 467     m->n_enabled_defer_events = m->n_enabled_time_events = m->n_io_events = 0;
 468     m->io_events_please_scan = m->time_events_please_scan = m->defer_events_please_scan = 0;
 469
 470     m->cached_next_time_event = NULL;
 471     m->prepared_timeout = 0;
 472
 473     m->pollfds = NULL;
 474     m->max_pollfds = m->n_pollfds = 0;
 475     m->rebuild_pollfds = 1;
 476
 477     m->quit = m->retval = 0;
 478
 479     m->api = vtable;
 480     m->api.userdata = m;
 481
 482     m->state = STATE_PASSIVE;
 483
 484     m->poll_func = NULL;
 485     m->poll_func_userdata = NULL;
 486     m->poll_func_ret = -1;
 487
 488     return m;
 489 }
 490
 491 static void cleanup_io_events(pa_mainloop *m, int force) {
 492     pa_io_event *e;
 493
 494     e = m->io_events;
 495     while (e) {
 496         pa_io_event *n = e->next;
 497
 498         if (!force && m->io_events_please_scan <= 0)
 499             break;
 500
 501         if (force || e->dead) {
 502             PA_LLIST_REMOVE(pa_io_event, m->io_events, e);
 503
 504             if (e->dead) {
 505                 assert(m->io_events_please_scan > 0);
 506                 m->io_events_please_scan--;
 507             }
 508
 509             if (e->destroy_callback)
 510                 e->destroy_callback(&m->api, e, e->userdata);
 511
 512             pa_xfree(e);
 513
 514             m->rebuild_pollfds = 1;
 515         }
 516
 517         e = n;
 518     }
 519
 520     assert(m->io_events_please_scan == 0);
 521 }
 522
 523 static void cleanup_time_events(pa_mainloop *m, int force) {
 524     pa_time_event *e;
 525
 526     e = m->time_events;
 527     while (e) {
 528         pa_time_event *n = e->next;
 529
 530         if (!force && m->time_events_please_scan <= 0)
 531             break;
 532
 533         if (force || e->dead) {
 534             PA_LLIST_REMOVE(pa_time_event, m->time_events, e);
 535
 536             if (e->dead) {
 537                 assert(m->time_events_please_scan > 0);
 538                 m->time_events_please_scan--;
 539             }
 540
 541             if (!e->dead && e->enabled) {
 542                 assert(m->n_enabled_time_events > 0);
 543                 m->n_enabled_time_events--;
 544             }
 545
 546             if (e->destroy_callback)
 547                 e->destroy_callback(&m->api, e, e->userdata);
 548
 549             pa_xfree(e);
 550         }
 551
 552         e = n;
 553     }
 554
 555     assert(m->time_events_please_scan == 0);
 556 }
 557
 558 static void cleanup_defer_events(pa_mainloop *m, int force) {
 559     pa_defer_event *e;
 560
 561     e = m->defer_events;
 562     while (e) {
 563         pa_defer_event *n = e->next;
 564
 565         if (!force && m->defer_events_please_scan <= 0)
 566             break;
 567
 568         if (force || e->dead) {
 569             PA_LLIST_REMOVE(pa_defer_event, m->defer_events, e);
 570
 571             if (e->dead) {
 572                 assert(m->defer_events_please_scan > 0);
 573                 m->defer_events_please_scan--;
 574             }
 575
 576             if (!e->dead && e->enabled) {
 577                 e->enabled = 0;
 578                 assert(m->n_enabled_defer_events > 0);
 579                 m->n_enabled_defer_events--;
 580             }
 581
 582             if (e->destroy_callback)
 583                 e->destroy_callback(&m->api, e, e->userdata);
 584
 585             pa_xfree(e);
 586         }
 587
 588         e = n;
 589     }
 590
 591     assert(m->defer_events_please_scan == 0);
 592 }
 593
 594
 595 void pa_mainloop_free(pa_mainloop* m) {
 596     assert(m);
 597
 598     cleanup_io_events(m, 1);
 599     cleanup_defer_events(m, 1);
 600     cleanup_time_events(m, 1);
 601
 602     pa_xfree(m->pollfds);
 603
 604     if (m->wakeup_pipe[0] >= 0)
 605         close(m->wakeup_pipe[0]);
 606     if (m->wakeup_pipe[1] >= 0)
 607         close(m->wakeup_pipe[1]);
 608
 609     pa_xfree(m);
 610 }
 611
 612 static void scan_dead(pa_mainloop *m) {
 613     assert(m);
 614
 615     if (m->io_events_please_scan)
 616         cleanup_io_events(m, 0);
 617
 618     if (m->time_events_please_scan)
 619         cleanup_time_events(m, 0);
 620
 621     if (m->defer_events_please_scan)
 622         cleanup_defer_events(m, 0);
 623 }
 624
 625 static void rebuild_pollfds(pa_mainloop *m) {
 626     pa_io_event*e;
 627     struct pollfd *p;
 628     unsigned l;
 629
 630     l = m->n_io_events + 1;
 631     if (m->max_pollfds < l) {
 632         l *= 2;
 633         m->pollfds = pa_xrealloc(m->pollfds, sizeof(struct pollfd)*l);
 634         m->max_pollfds = l;
 635     }
 636
 637     m->n_pollfds = 0;
 638     p = m->pollfds;
 639
 640     if (m->wakeup_pipe[0] >= 0) {
 641         m->pollfds[0].fd = m->wakeup_pipe[0];
 642         m->pollfds[0].events = POLLIN;
 643         m->pollfds[0].revents = 0;
 644         p++;
 645         m->n_pollfds++;
 646     }
 647
 648     for (e = m->io_events; e; e = e->next) {
 649         if (e->dead) {
 650             e->pollfd = NULL;
 651             continue;
 652         }
 653
 654         e->pollfd = p;
 655         p->fd = e->fd;
 656         p->events = map_flags_to_libc(e->events);
 657         p->revents = 0;
 658
 659         p++;
 660         m->n_pollfds++;
 661     }
 662
 663     m->rebuild_pollfds = 0;
 664 }
 665
 666 static int dispatch_pollfds(pa_mainloop *m) {
 667     pa_io_event *e;
 668     int r = 0, k;
 669
 670     assert(m->poll_func_ret > 0);
 671
 672     for (e = m->io_events, k = m->poll_func_ret; e && !m->quit && k > 0; e = e->next) {
 673         if (e->dead || !e->pollfd || !e->pollfd->revents)
 674             continue;
 675
 676         assert(e->pollfd->fd == e->fd && e->callback);
 677         e->callback(&m->api, e, e->fd, map_flags_from_libc(e->pollfd->revents), e->userdata);
 678         e->pollfd->revents = 0;
 679         r++;
 680
 681         k--;
 682     }
 683
 684     return r;
 685 }
 686
 687 static int dispatch_defer(pa_mainloop *m) {
 688     pa_defer_event *e;
 689     int r = 0;
 690
 691     if (m->n_enabled_defer_events <= 0)
 692         return 0;
 693
 694     for (e = m->defer_events; e && !m->quit; e = e->next) {
 695         if (e->dead || !e->enabled)
 696             continue;
 697
 698         assert(e->callback);
 699         e->callback(&m->api, e, e->userdata);
 700         r++;
 701     }
 702
 703     return r;
 704 }
 705
 706 static pa_time_event* find_next_time_event(pa_mainloop *m) {
 707     pa_time_event *t, *n = NULL;
 708     assert(m);
 709
 710     if (m->cached_next_time_event)
 711         return m->cached_next_time_event;
 712
 713     for (t = m->time_events; t; t = t->next) {
 714
 715         if (t->dead || !t->enabled)
 716             continue;
 717
 718         if (!n || pa_timeval_cmp(&t->timeval, &n->timeval) < 0) {
 719             n = t;
 720
 721             /* Shortcut for tv = { 0, 0 } */
 722             if (n->timeval.tv_sec <= 0)
 723                 break;
 724         }
 725     }
 726
 727     m->cached_next_time_event = n;
 728     return n;
 729 }
 730
 731 static int calc_next_timeout(pa_mainloop *m) {
 732     pa_time_event *t;
 733     struct timeval now;
 734     pa_usec_t usec;
 735
 736     if (!m->n_enabled_time_events)
 737         return -1;
 738
 739     t = find_next_time_event(m);
 740     assert(t);
 741
 742     if (t->timeval.tv_sec <= 0)
 743         return 0;
 744
 745     pa_gettimeofday(&now);
 746
 747     if (pa_timeval_cmp(&t->timeval, &now) <= 0)
 748         return 0;
 749
 750     usec = pa_timeval_diff(&t->timeval, &now);
 751     return (int) (usec / 1000);
 752 }
 753
 754 static int dispatch_timeout(pa_mainloop *m) {
 755     pa_time_event *e;
 756     struct timeval now;
 757     int r = 0;
 758     assert(m);
 759
 760     if (m->n_enabled_time_events <= 0)
 761         return 0;
 762
 763     pa_gettimeofday(&now);
 764
 765     for (e = m->time_events; e && !m->quit; e = e->next) {
 766
 767         if (e->dead || !e->enabled)
 768             continue;
 769
 770         if (pa_timeval_cmp(&e->timeval, &now) <= 0) {
 771             assert(e->callback);
 772
 773             /* Disable time event */
 774             mainloop_time_restart(e, NULL);
 775
 776             e->callback(&m->api, e, &e->timeval, e->userdata);
 777
 778             r++;
 779         }
 780     }
 781
 782     return r;
 783 }
 784
 785 void pa_mainloop_wakeup(pa_mainloop *m) {
 786     char c = 'W';
 787     assert(m);
 788
 789     if (m->wakeup_pipe[1] >= 0 && m->state == STATE_POLLING) {
 790         pa_write(m->wakeup_pipe[1], &c, sizeof(c), &m->wakeup_pipe_type);
 791         m->wakeup_requested++;
 792     }
 793 }
 794
 795 static void clear_wakeup(pa_mainloop *m) {
 796     char c[10];
 797
 798     assert(m);
 799
 800     if (m->wakeup_pipe[0] < 0)
 801         return;
 802
 803     if (m->wakeup_requested) {
 804         while (pa_read(m->wakeup_pipe[0], &c, sizeof(c), &m->wakeup_pipe_type) == sizeof(c));
 805         m->wakeup_requested = 0;
 806     }
 807 }
 808
 809 int pa_mainloop_prepare(pa_mainloop *m, int timeout) {
 810     assert(m);
 811     assert(m->state == STATE_PASSIVE);
 812
 813     clear_wakeup(m);
 814     scan_dead(m);
 815
 816     if (m->quit)
 817         goto quit;
 818
 819     if (m->n_enabled_defer_events <= 0) {
 820         if (m->rebuild_pollfds)
 821             rebuild_pollfds(m);
 822
 823         m->prepared_timeout = calc_next_timeout(m);
 824         if (timeout >= 0 && (timeout < m->prepared_timeout || m->prepared_timeout < 0))
 825             m->prepared_timeout = timeout;
 826     }
 827
 828     m->state = STATE_PREPARED;
 829     return 0;
 830
 831 quit:
 832     m->state = STATE_QUIT;
 833     return -2;
 834 }
 835
 836 int pa_mainloop_poll(pa_mainloop *m) {
 837     assert(m);
 838     assert(m->state == STATE_PREPARED);
 839
 840     if (m->quit)
 841         goto quit;
 842
 843     m->state = STATE_POLLING;
 844
 845     if (m->n_enabled_defer_events )
 846         m->poll_func_ret = 0;
 847     else {
 848         assert(!m->rebuild_pollfds);
 849
 850         if (m->poll_func)
 851             m->poll_func_ret = m->poll_func(m->pollfds, m->n_pollfds, m->prepared_timeout, m->poll_func_userdata);
 852         else
 853             m->poll_func_ret = poll(m->pollfds, m->n_pollfds, m->prepared_timeout);
 854
 855         if (m->poll_func_ret < 0) {
 856             if (errno == EINTR)
 857                 m->poll_func_ret = 0;
 858             else
 859                 pa_log("poll(): %s", pa_cstrerror(errno));
 860         }
 861     }
 862
 863     m->state = m->poll_func_ret < 0 ? STATE_PASSIVE : STATE_POLLED;
 864     return m->poll_func_ret;
 865
 866 quit:
 867     m->state = STATE_QUIT;
 868     return -2;
 869 }
 870
 871 int pa_mainloop_dispatch(pa_mainloop *m) {
 872     int dispatched = 0;
 873
 874     assert(m);
 875     assert(m->state == STATE_POLLED);
 876
 877     if (m->quit)
 878         goto quit;
 879
 880     if (m->n_enabled_defer_events)
 881         dispatched += dispatch_defer(m);
 882     else {
 883         if (m->n_enabled_time_events)
 884             dispatched += dispatch_timeout(m);
 885
 886         if (m->quit)
 887             goto quit;
 888
 889         if (m->poll_func_ret > 0)
 890             dispatched += dispatch_pollfds(m);
 891     }
 892
 893     if (m->quit)
 894         goto quit;
 895
 896     m->state = STATE_PASSIVE;
 897
 898     return dispatched;
 899
 900 quit:
 901     m->state = STATE_QUIT;
 902     return -2;
 903 }
 904
 905 int pa_mainloop_get_retval(pa_mainloop *m) {
 906     assert(m);
 907     return m->retval;
 908 }
 909
 910 int pa_mainloop_iterate(pa_mainloop *m, int block, int *retval) {
 911     int r;
 912     assert(m);
 913
 914     if ((r = pa_mainloop_prepare(m, block ? -1 : 0)) < 0)
 915         goto quit;
 916
 917     if ((r = pa_mainloop_poll(m)) < 0)
 918         goto quit;
 919
 920     if ((r = pa_mainloop_dispatch(m)) < 0)
 921         goto quit;
 922
 923     return r;
 924
 925 quit:
 926
 927     if ((r == -2) && retval)
 928         *retval = pa_mainloop_get_retval(m);
 929     return r;
 930 }
 931
 932 int pa_mainloop_run(pa_mainloop *m, int *retval) {
 933     int r;
 934
 935     while ((r = pa_mainloop_iterate(m, 1, retval)) >= 0);
 936
 937     if (r == -2)
 938         return 1;
 939     else if (r < 0)
 940         return -1;
 941     else
 942         return 0;
 943 }
 944
 945 void pa_mainloop_quit(pa_mainloop *m, int retval) {
 946     assert(m);
 947
 948     m->quit = 1;
 949     m->retval = retval;
 950     pa_mainloop_wakeup(m);
 951 }
 952
 953 pa_mainloop_api* pa_mainloop_get_api(pa_mainloop*m) {
 954     assert(m);
 955     return &m->api;
 956 }
 957
 958 void pa_mainloop_set_poll_func(pa_mainloop *m, pa_poll_func poll_func, void *userdata) {
 959     assert(m);
 960
 961     m->poll_func = poll_func;
 962     m->poll_func_userdata = userdata;
 963 }