code.delx.au - pulseaudio/blob - src/modules/module-udev-detect.c

   1 /***
   2   This file is part of PulseAudio.
   3
   4   Copyright 2009 Lennart Poettering
   5
   6   PulseAudio is free software; you can redistribute it and/or modify
   7   it under the terms of the GNU Lesser General Public License as
   8   published by the Free Software Foundation; either version 2.1 of the
   9   License, or (at your option) any later version.
  10
  11   PulseAudio is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public
  17   License along with PulseAudio; if not, write to the Free Software
  18   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  19   USA.
  20 ***/
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26 #include <errno.h>
  27 #include <limits.h>
  28 #include <dirent.h>
  29 #include <sys/inotify.h>
  30 #include <libudev.h>
  31
  32 #include <pulse/timeval.h>
  33
  34 #include <pulsecore/modargs.h>
  35 #include <pulsecore/core-error.h>
  36 #include <pulsecore/core-util.h>
  37 #include <pulsecore/namereg.h>
  38 #include <pulsecore/ratelimit.h>
  39
  40 #include "module-udev-detect-symdef.h"
  41
  42 PA_MODULE_AUTHOR("Lennart Poettering");
  43 PA_MODULE_DESCRIPTION("Detect available audio hardware and load matching drivers");
  44 PA_MODULE_VERSION(PACKAGE_VERSION);
  45 PA_MODULE_LOAD_ONCE(TRUE);
  46 PA_MODULE_USAGE(
  47         "tsched=<enable system timer based scheduling mode?> "
  48         "ignore_dB=<ignore dB information from the device?>");
  49
  50 struct device {
  51     char *path;
  52     pa_bool_t need_verify;
  53     char *card_name;
  54     char *args;
  55     uint32_t module;
  56     pa_ratelimit ratelimit;
  57 };
  58
  59 struct userdata {
  60     pa_core *core;
  61     pa_hashmap *devices;
  62
  63     pa_bool_t use_tsched:1;
  64     pa_bool_t ignore_dB:1;
  65
  66     struct udev* udev;
  67     struct udev_monitor *monitor;
  68     pa_io_event *udev_io;
  69
  70     int inotify_fd;
  71     pa_io_event *inotify_io;
  72 };
  73
  74 static const char* const valid_modargs[] = {
  75     "tsched",
  76     "ignore_dB",
  77     NULL
  78 };
  79
  80 static int setup_inotify(struct userdata *u);
  81
  82 static void device_free(struct device *d) {
  83     pa_assert(d);
  84
  85     pa_xfree(d->path);
  86     pa_xfree(d->card_name);
  87     pa_xfree(d->args);
  88     pa_xfree(d);
  89 }
  90
  91 static const char *path_get_card_id(const char *path) {
  92     const char *e;
  93
  94     if (!path)
  95         return NULL;
  96
  97     if (!(e = strrchr(path, '/')))
  98         return NULL;
  99
 100     if (!pa_startswith(e, "/card"))
 101         return NULL;
 102
 103     return e + 5;
 104 }
 105
 106 static const char *pa_udev_get_sysattr(const char *card_idx, const char *name);
 107
 108 static pa_bool_t is_card_busy(const char *id) {
 109     const char *pcm_class;
 110     char *card_path = NULL, *pcm_path = NULL, *sub_status = NULL,
 111          *sysfs_path = NULL;
 112     DIR *card_dir = NULL, *pcm_dir = NULL;
 113     FILE *status_file = NULL;
 114     size_t len;
 115     struct dirent *space = NULL, *de;
 116     pa_bool_t busy = FALSE, is_modem = FALSE;
 117     int r;
 118
 119     pa_assert(id);
 120
 121     /* This simply uses /proc/asound/card.../pcm.../sub.../status to
 122      * check whether there is still a process using this audio device. */
 123
 124     card_path = pa_sprintf_malloc("/proc/asound/card%s", id);
 125
 126     if (!(card_dir = opendir(card_path))) {
 127         pa_log_warn("Failed to open %s: %s", card_path, pa_cstrerror(errno));
 128         goto fail;
 129     }
 130
 131     len = offsetof(struct dirent, d_name) + fpathconf(dirfd(card_dir), _PC_NAME_MAX) + 1;
 132     space = pa_xmalloc(len);
 133
 134     /* Also check /sys/class/sound/card.../pcmC...D6p/pcm_class. An HDA
 135      * modem can be used simultaneously with generic playback/record. */
 136
 137     pa_xfree(sysfs_path);
 138     sysfs_path = pa_sprintf_malloc("pcmC%sD6p/pcm_class", id);
 139
 140     pcm_class = pa_udev_get_sysattr(id, sysfs_path);
 141
 142     if (pcm_class && pa_streq(pcm_class, "modem"))
 143         is_modem = TRUE;
 144
 145     for (;;) {
 146         de = NULL;
 147
 148         if ((r = readdir_r(card_dir, space, &de)) != 0) {
 149             pa_log_warn("readdir_r() failed: %s", pa_cstrerror(r));
 150             goto fail;
 151         }
 152
 153         if (!de)
 154             break;
 155
 156         if (!pa_startswith(de->d_name, "pcm"))
 157             continue;
 158
 159         pa_xfree(pcm_path);
 160         pcm_path = pa_sprintf_malloc("%s/%s", card_path, de->d_name);
 161
 162         if (pcm_dir)
 163             closedir(pcm_dir);
 164
 165         if (!(pcm_dir = opendir(pcm_path))) {
 166             pa_log_warn("Failed to open %s: %s", pcm_path, pa_cstrerror(errno));
 167             continue;
 168         }
 169
 170         for (;;) {
 171             char line[32];
 172
 173             if ((r = readdir_r(pcm_dir, space, &de)) != 0) {
 174                 pa_log_warn("readdir_r() failed: %s", pa_cstrerror(r));
 175                 goto fail;
 176             }
 177
 178             if (!de)
 179                 break;
 180
 181             if (!pa_startswith(de->d_name, "sub"))
 182                 continue;
 183
 184             pa_xfree(sub_status);
 185             sub_status = pa_sprintf_malloc("%s/%s/status", pcm_path, de->d_name);
 186
 187             if (status_file)
 188                 fclose(status_file);
 189
 190             if (!(status_file = pa_fopen_cloexec(sub_status, "r"))) {
 191                 pa_log_warn("Failed to open %s: %s", sub_status, pa_cstrerror(errno));
 192                 continue;
 193             }
 194
 195             if (!(fgets(line, sizeof(line)-1, status_file))) {
 196                 pa_log_warn("Failed to read from %s: %s", sub_status, pa_cstrerror(errno));
 197                 continue;
 198             }
 199
 200             if (!is_modem && !pa_streq(line, "closed\n")) {
 201                 busy = TRUE;
 202                 break;
 203             }
 204         }
 205     }
 206
 207 fail:
 208
 209     pa_xfree(card_path);
 210     pa_xfree(pcm_path);
 211     pa_xfree(sysfs_path);
 212     pa_xfree(sub_status);
 213     pa_xfree(space);
 214
 215     if (card_dir)
 216         closedir(card_dir);
 217
 218     if (pcm_dir)
 219         closedir(pcm_dir);
 220
 221     if (status_file)
 222         fclose(status_file);
 223
 224     return busy;
 225 }
 226
 227 static void verify_access(struct userdata *u, struct device *d) {
 228     char *cd;
 229     pa_card *card;
 230     pa_bool_t accessible;
 231
 232     pa_assert(u);
 233     pa_assert(d);
 234
 235     cd = pa_sprintf_malloc("%s/snd/controlC%s", udev_get_dev_path(u->udev), path_get_card_id(d->path));
 236     accessible = access(cd, R_OK|W_OK) >= 0;
 237     pa_log_debug("%s is accessible: %s", cd, pa_yes_no(accessible));
 238
 239     pa_xfree(cd);
 240
 241     if (d->module == PA_INVALID_INDEX) {
 242
 243         /* If we are not loaded, try to load */
 244
 245         if (accessible) {
 246             pa_module *m;
 247             pa_bool_t busy;
 248
 249             /* Check if any of the PCM devices that belong to this
 250              * card are currently busy. If they are, don't try to load
 251              * right now, to make sure the probing phase can
 252              * successfully complete. When the current user of the
 253              * device closes it we will get another notification via
 254              * inotify and can then recheck. */
 255
 256             busy = is_card_busy(path_get_card_id(d->path));
 257             pa_log_debug("%s is busy: %s", d->path, pa_yes_no(busy));
 258
 259             if (!busy) {
 260
 261                 /* So, why do we rate limit here? It's certainly ugly,
 262                  * but there seems to be no other way. Problem is
 263                  * this: if we are unable to configure/probe an audio
 264                  * device after opening it we will close it again and
 265                  * the module initialization will fail. This will then
 266                  * cause an inotify event on the device node which
 267                  * will be forwarded to us. We then try to reopen the
 268                  * audio device again, practically entering a busy
 269                  * loop.
 270                  *
 271                  * A clean fix would be if we would be able to ignore
 272                  * our own inotify close events. However, inotify
 273                  * lacks such functionality. Also, during probing of
 274                  * the device we cannot really distuingish between
 275                  * other processes causing EBUSY or ourselves, which
 276                  * means we have no way to figure out if the probing
 277                  * during opening was canceled by a "try again"
 278                  * failure or a "fatal" failure. */
 279
 280                 if (pa_ratelimit_test(&d->ratelimit)) {
 281                     pa_log_debug("Loading module-alsa-card with arguments '%s'", d->args);
 282                     m = pa_module_load(u->core, "module-alsa-card", d->args);
 283
 284                     if (m) {
 285                         d->module = m->index;
 286                         pa_log_info("Card %s (%s) module loaded.", d->path, d->card_name);
 287                     } else
 288                         pa_log_info("Card %s (%s) failed to load module.", d->path, d->card_name);
 289                 } else
 290                     pa_log_warn("Tried to configure %s (%s) more often than %u times in %llus",
 291                                 d->path,
 292                                 d->card_name,
 293                                 d->ratelimit.burst,
 294                                 (long long unsigned) (d->ratelimit.interval / PA_USEC_PER_SEC));
 295             }
 296         }
 297
 298     } else {
 299
 300         /* If we are already loaded update suspend status with
 301          * accessible boolean */
 302
 303         if ((card = pa_namereg_get(u->core, d->card_name, PA_NAMEREG_CARD)))
 304             pa_card_suspend(card, !accessible, PA_SUSPEND_SESSION);
 305     }
 306 }
 307
 308 static void card_changed(struct userdata *u, struct udev_device *dev) {
 309     struct device *d;
 310     const char *path;
 311     const char *t;
 312     char *n;
 313
 314     pa_assert(u);
 315     pa_assert(dev);
 316
 317     /* Maybe /dev/snd is now available? */
 318     setup_inotify(u);
 319
 320     path = udev_device_get_devpath(dev);
 321
 322     if ((d = pa_hashmap_get(u->devices, path))) {
 323         verify_access(u, d);
 324         return;
 325     }
 326
 327     d = pa_xnew0(struct device, 1);
 328     d->path = pa_xstrdup(path);
 329     d->module = PA_INVALID_INDEX;
 330     PA_INIT_RATELIMIT(d->ratelimit, 10*PA_USEC_PER_SEC, 5);
 331
 332     if (!(t = udev_device_get_property_value(dev, "PULSE_NAME")))
 333         if (!(t = udev_device_get_property_value(dev, "ID_ID")))
 334             if (!(t = udev_device_get_property_value(dev, "ID_PATH")))
 335                 t = path_get_card_id(path);
 336
 337     n = pa_namereg_make_valid_name(t);
 338     d->card_name = pa_sprintf_malloc("alsa_card.%s", n);
 339     d->args = pa_sprintf_malloc("device_id=\"%s\" "
 340                                 "name=\"%s\" "
 341                                 "card_name=\"%s\" "
 342                                 "tsched=%s "
 343                                 "ignore_dB=%s "
 344                                 "card_properties=\"module-udev-detect.discovered=1\"",
 345                                 path_get_card_id(path),
 346                                 n,
 347                                 d->card_name,
 348                                 pa_yes_no(u->use_tsched),
 349                                 pa_yes_no(u->ignore_dB));
 350     pa_xfree(n);
 351
 352     pa_hashmap_put(u->devices, d->path, d);
 353
 354     verify_access(u, d);
 355 }
 356
 357 static void remove_card(struct userdata *u, struct udev_device *dev) {
 358     struct device *d;
 359
 360     pa_assert(u);
 361     pa_assert(dev);
 362
 363     if (!(d = pa_hashmap_remove(u->devices, udev_device_get_devpath(dev))))
 364         return;
 365
 366     pa_log_info("Card %s removed.", d->path);
 367
 368     if (d->module != PA_INVALID_INDEX)
 369         pa_module_unload_request_by_index(u->core, d->module, TRUE);
 370
 371     device_free(d);
 372 }
 373
 374 static void process_device(struct userdata *u, struct udev_device *dev) {
 375     const char *action, *ff;
 376
 377     pa_assert(u);
 378     pa_assert(dev);
 379
 380     if (udev_device_get_property_value(dev, "PULSE_IGNORE")) {
 381         pa_log_debug("Ignoring %s, because marked so.", udev_device_get_devpath(dev));
 382         return;
 383     }
 384
 385     if ((ff = udev_device_get_property_value(dev, "SOUND_CLASS")) &&
 386         pa_streq(ff, "modem")) {
 387         pa_log_debug("Ignoring %s, because it is a modem.", udev_device_get_devpath(dev));
 388         return;
 389     }
 390
 391     action = udev_device_get_action(dev);
 392
 393     if (action && pa_streq(action, "remove"))
 394         remove_card(u, dev);
 395     else if ((!action || pa_streq(action, "change")) &&
 396              udev_device_get_property_value(dev, "SOUND_INITIALIZED"))
 397         card_changed(u, dev);
 398
 399     /* For an explanation why we don't look for 'add' events here
 400      * have a look into /lib/udev/rules.d/78-sound-card.rules! */
 401 }
 402
 403 static void process_path(struct userdata *u, const char *path) {
 404     struct udev_device *dev;
 405
 406     if (!path_get_card_id(path))
 407         return;
 408
 409     if (!(dev = udev_device_new_from_syspath(u->udev, path))) {
 410         pa_log("Failed to get udev device object from udev.");
 411         return;
 412     }
 413
 414     process_device(u, dev);
 415     udev_device_unref(dev);
 416 }
 417
 418 static void monitor_cb(
 419         pa_mainloop_api*a,
 420         pa_io_event* e,
 421         int fd,
 422         pa_io_event_flags_t events,
 423         void *userdata) {
 424
 425     struct userdata *u = userdata;
 426     struct udev_device *dev;
 427
 428     pa_assert(a);
 429
 430     if (!(dev = udev_monitor_receive_device(u->monitor))) {
 431         pa_log("Failed to get udev device object from monitor.");
 432         goto fail;
 433     }
 434
 435     if (!path_get_card_id(udev_device_get_devpath(dev))) {
 436         udev_device_unref(dev);
 437         return;
 438     }
 439
 440     process_device(u, dev);
 441     udev_device_unref(dev);
 442     return;
 443
 444 fail:
 445     a->io_free(u->udev_io);
 446     u->udev_io = NULL;
 447 }
 448
 449 static pa_bool_t pcm_node_belongs_to_device(
 450         struct device *d,
 451         const char *node) {
 452
 453     char *cd;
 454     pa_bool_t b;
 455
 456     cd = pa_sprintf_malloc("pcmC%sD", path_get_card_id(d->path));
 457     b = pa_startswith(node, cd);
 458     pa_xfree(cd);
 459
 460     return b;
 461 }
 462
 463 static pa_bool_t control_node_belongs_to_device(
 464         struct device *d,
 465         const char *node) {
 466
 467     char *cd;
 468     pa_bool_t b;
 469
 470     cd = pa_sprintf_malloc("controlC%s", path_get_card_id(d->path));
 471     b = pa_streq(node, cd);
 472     pa_xfree(cd);
 473
 474     return b;
 475 }
 476
 477 static void inotify_cb(
 478         pa_mainloop_api*a,
 479         pa_io_event* e,
 480         int fd,
 481         pa_io_event_flags_t events,
 482         void *userdata) {
 483
 484     struct {
 485         struct inotify_event e;
 486         char name[NAME_MAX];
 487     } buf;
 488     struct userdata *u = userdata;
 489     static int type = 0;
 490     pa_bool_t deleted = FALSE;
 491     struct device *d;
 492     void *state;
 493
 494     for (;;) {
 495         ssize_t r;
 496         struct inotify_event *event;
 497
 498         pa_zero(buf);
 499         if ((r = pa_read(fd, &buf, sizeof(buf), &type)) <= 0) {
 500
 501             if (r < 0 && errno == EAGAIN)
 502                 break;
 503
 504             pa_log("read() from inotify failed: %s", r < 0 ? pa_cstrerror(errno) : "EOF");
 505             goto fail;
 506         }
 507
 508         event = &buf.e;
 509         while (r > 0) {
 510             size_t len;
 511
 512             if ((size_t) r < sizeof(struct inotify_event)) {
 513                 pa_log("read() too short.");
 514                 goto fail;
 515             }
 516
 517             len = sizeof(struct inotify_event) + event->len;
 518
 519             if ((size_t) r < len) {
 520                 pa_log("Payload missing.");
 521                 goto fail;
 522             }
 523
 524             /* From udev we get the guarantee that the control
 525              * device's ACL is changed last. To avoid races when ACLs
 526              * are changed we hence watch only the control device */
 527             if (((event->mask & IN_ATTRIB) && pa_startswith(event->name, "controlC")))
 528                 PA_HASHMAP_FOREACH(d, u->devices, state)
 529                     if (control_node_belongs_to_device(d, event->name))
 530                         d->need_verify = TRUE;
 531
 532             /* ALSA doesn't really give us any guarantee on the closing
 533              * order, so let's simply hope */
 534             if (((event->mask & IN_CLOSE_WRITE) && pa_startswith(event->name, "pcmC")))
 535                 PA_HASHMAP_FOREACH(d, u->devices, state)
 536                     if (pcm_node_belongs_to_device(d, event->name))
 537                         d->need_verify = TRUE;
 538
 539             /* /dev/snd/ might have been removed */
 540             if ((event->mask & (IN_DELETE_SELF|IN_MOVE_SELF)))
 541                 deleted = TRUE;
 542
 543             event = (struct inotify_event*) ((uint8_t*) event + len);
 544             r -= len;
 545         }
 546     }
 547
 548     PA_HASHMAP_FOREACH(d, u->devices, state)
 549         if (d->need_verify) {
 550             d->need_verify = FALSE;
 551             verify_access(u, d);
 552         }
 553
 554     if (!deleted)
 555         return;
 556
 557 fail:
 558     if (u->inotify_io) {
 559         a->io_free(u->inotify_io);
 560         u->inotify_io = NULL;
 561     }
 562
 563     if (u->inotify_fd >= 0) {
 564         pa_close(u->inotify_fd);
 565         u->inotify_fd = -1;
 566     }
 567 }
 568
 569 static int setup_inotify(struct userdata *u) {
 570     char *dev_snd;
 571     int r;
 572
 573     if (u->inotify_fd >= 0)
 574         return 0;
 575
 576     if ((u->inotify_fd = inotify_init1(IN_CLOEXEC|IN_NONBLOCK)) < 0) {
 577         pa_log("inotify_init1() failed: %s", pa_cstrerror(errno));
 578         return -1;
 579     }
 580
 581     dev_snd = pa_sprintf_malloc("%s/snd", udev_get_dev_path(u->udev));
 582     r = inotify_add_watch(u->inotify_fd, dev_snd, IN_ATTRIB|IN_CLOSE_WRITE|IN_DELETE_SELF|IN_MOVE_SELF);
 583     pa_xfree(dev_snd);
 584
 585     if (r < 0) {
 586         int saved_errno = errno;
 587
 588         pa_close(u->inotify_fd);
 589         u->inotify_fd = -1;
 590
 591         if (saved_errno == ENOENT) {
 592             pa_log_debug("/dev/snd/ is apparently not existing yet, retrying to create inotify watch later.");
 593             return 0;
 594         }
 595
 596         if (saved_errno == ENOSPC) {
 597             pa_log("You apparently ran out of inotify watches, probably because Tracker/Beagle took them all away. "
 598                    "I wished people would do their homework first and fix inotify before using it for watching whole "
 599                    "directory trees which is something the current inotify is certainly not useful for. "
 600                    "Please make sure to drop the Tracker/Beagle guys a line complaining about their broken use of inotify.");
 601             return 0;
 602         }
 603
 604         pa_log("inotify_add_watch() failed: %s", pa_cstrerror(saved_errno));
 605         return -1;
 606     }
 607
 608     pa_assert_se(u->inotify_io = u->core->mainloop->io_new(u->core->mainloop, u->inotify_fd, PA_IO_EVENT_INPUT, inotify_cb, u));
 609
 610     return 0;
 611 }
 612
 613 static const char *pa_udev_get_sysattr(const char *card_idx, const char *name) {
 614     struct udev *udev;
 615     struct udev_device *card = NULL;
 616     char *t, *r = NULL;
 617     const char *v;
 618
 619     pa_assert(card_idx);
 620     pa_assert(name);
 621
 622     if (!(udev = udev_new())) {
 623         pa_log_error("Failed to allocate udev context.");
 624         goto finish;
 625     }
 626
 627     t = pa_sprintf_malloc("%s/class/sound/card%s", udev_get_sys_path(udev), card_idx);
 628     card = udev_device_new_from_syspath(udev, t);
 629     pa_xfree(t);
 630
 631     if (!card) {
 632         pa_log_error("Failed to get card object.");
 633         goto finish;
 634     }
 635
 636     if ((v = udev_device_get_sysattr_value(card, name)) && *v)
 637         r = pa_xstrdup(v);
 638
 639 finish:
 640
 641     if (card)
 642         udev_device_unref(card);
 643
 644     if (udev)
 645         udev_unref(udev);
 646
 647     return r;
 648 }
 649
 650 int pa__init(pa_module *m) {
 651     struct userdata *u = NULL;
 652     pa_modargs *ma;
 653     struct udev_enumerate *enumerate = NULL;
 654     struct udev_list_entry *item = NULL, *first = NULL;
 655     int fd;
 656     pa_bool_t use_tsched = TRUE, ignore_dB = FALSE;
 657
 658     pa_assert(m);
 659
 660     if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
 661         pa_log("Failed to parse module arguments");
 662         goto fail;
 663     }
 664
 665     m->userdata = u = pa_xnew0(struct userdata, 1);
 666     u->core = m->core;
 667     u->devices = pa_hashmap_new(pa_idxset_string_hash_func, pa_idxset_string_compare_func);
 668     u->inotify_fd = -1;
 669
 670     if (pa_modargs_get_value_boolean(ma, "tsched", &use_tsched) < 0) {
 671         pa_log("Failed to parse tsched= argument.");
 672         goto fail;
 673     }
 674     u->use_tsched = use_tsched;
 675
 676     if (pa_modargs_get_value_boolean(ma, "ignore_dB", &ignore_dB) < 0) {
 677         pa_log("Failed to parse ignore_dB= argument.");
 678         goto fail;
 679     }
 680     u->ignore_dB = ignore_dB;
 681
 682     if (!(u->udev = udev_new())) {
 683         pa_log("Failed to initialize udev library.");
 684         goto fail;
 685     }
 686
 687     if (setup_inotify(u) < 0)
 688         goto fail;
 689
 690     if (!(u->monitor = udev_monitor_new_from_netlink(u->udev, "udev"))) {
 691         pa_log("Failed to initialize monitor.");
 692         goto fail;
 693     }
 694
 695     if (udev_monitor_filter_add_match_subsystem_devtype(u->monitor, "sound", NULL) < 0) {
 696         pa_log("Failed to subscribe to sound devices.");
 697         goto fail;
 698     }
 699
 700     errno = 0;
 701     if (udev_monitor_enable_receiving(u->monitor) < 0) {
 702         pa_log("Failed to enable monitor: %s", pa_cstrerror(errno));
 703         if (errno == EPERM)
 704             pa_log_info("Most likely your kernel is simply too old and "
 705                         "allows only priviliged processes to listen to device events. "
 706                         "Please upgrade your kernel to at least 2.6.30.");
 707         goto fail;
 708     }
 709
 710     if ((fd = udev_monitor_get_fd(u->monitor)) < 0) {
 711         pa_log("Failed to get udev monitor fd.");
 712         goto fail;
 713     }
 714
 715     pa_assert_se(u->udev_io = u->core->mainloop->io_new(u->core->mainloop, fd, PA_IO_EVENT_INPUT, monitor_cb, u));
 716
 717     if (!(enumerate = udev_enumerate_new(u->udev))) {
 718         pa_log("Failed to initialize udev enumerator.");
 719         goto fail;
 720     }
 721
 722     if (udev_enumerate_add_match_subsystem(enumerate, "sound") < 0) {
 723         pa_log("Failed to match to subsystem.");
 724         goto fail;
 725     }
 726
 727     if (udev_enumerate_scan_devices(enumerate) < 0) {
 728         pa_log("Failed to scan for devices.");
 729         goto fail;
 730     }
 731
 732     first = udev_enumerate_get_list_entry(enumerate);
 733     udev_list_entry_foreach(item, first)
 734         process_path(u, udev_list_entry_get_name(item));
 735
 736     udev_enumerate_unref(enumerate);
 737
 738     pa_log_info("Found %u cards.", pa_hashmap_size(u->devices));
 739
 740     pa_modargs_free(ma);
 741
 742     return 0;
 743
 744 fail:
 745
 746     if (enumerate)
 747         udev_enumerate_unref(enumerate);
 748
 749     if (ma)
 750         pa_modargs_free(ma);
 751
 752     pa__done(m);
 753
 754     return -1;
 755 }
 756
 757 void pa__done(pa_module *m) {
 758     struct userdata *u;
 759
 760     pa_assert(m);
 761
 762     if (!(u = m->userdata))
 763         return;
 764
 765     if (u->udev_io)
 766         m->core->mainloop->io_free(u->udev_io);
 767
 768     if (u->monitor)
 769         udev_monitor_unref(u->monitor);
 770
 771     if (u->udev)
 772         udev_unref(u->udev);
 773
 774     if (u->inotify_io)
 775         m->core->mainloop->io_free(u->inotify_io);
 776
 777     if (u->inotify_fd >= 0)
 778         pa_close(u->inotify_fd);
 779
 780     if (u->devices) {
 781         struct device *d;
 782
 783         while ((d = pa_hashmap_steal_first(u->devices)))
 784             device_free(d);
 785
 786         pa_hashmap_free(u->devices, NULL, NULL);
 787     }
 788
 789     pa_xfree(u);
 790 }