audiod.c

   1 /*
   2  * Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>
   3  *
   4  * Licensed under the GPL v2. For licencing details see COPYING.
   5  */
   6
   7 /** \file audiod.c The paraslash's audio daemon. */
   8
   9 #include <netinet/in.h>
  10 #include <sys/socket.h>
  11 #include <regex.h>
  12 #include <sys/types.h>
  13 #include <arpa/inet.h>
  14 #include <sys/un.h>
  15 #include <netdb.h>
  16 #include <signal.h>
  17 #include <pwd.h>
  18 #include <lopsub.h>
  19
  20 #include "audiod.lsg.h"
  21 #include "recv_cmd.lsg.h"
  22 #include "para.h"
  23 #include "error.h"
  24 #include "crypt.h"
  25 #include "list.h"
  26 #include "sched.h"
  27 #include "buffer_tree.h"
  28 #include "recv.h"
  29 #include "filter.h"
  30 #include "grab_client.h"
  31 #include "client.h"
  32 #include "audiod.h"
  33 #include "net.h"
  34 #include "daemon.h"
  35 #include "string.h"
  36 #include "fd.h"
  37 #include "write.h"
  38 #include "signal.h"
  39 #include "version.h"
  40
  41 /** Array of error strings. */
  42 DEFINE_PARA_ERRLIST;
  43
  44 static struct lls_parse_result *lpr;
  45 #define CMD_PTR (lls_cmd(0, audiod_suite))
  46 #define OPT_RESULT(_name) (lls_opt_result(LSG_AUDIOD_PARA_AUDIOD_OPT_ ## _name, lpr))
  47 #define OPT_GIVEN(_name) (lls_opt_given(OPT_RESULT(_name)))
  48 #define OPT_STRING_VAL(_name) (lls_string_val(0, OPT_RESULT(_name)))
  49 #define OPT_UINT32_VAL(_name) (lls_uint32_val(0, OPT_RESULT(_name)))
  50 #define ENUM_STRING_VAL(_name) (lls_enum_string_val(OPT_UINT32_VAL(_name), \
  51         lls_opt(LSG_AUDIOD_PARA_AUDIOD_OPT_ ## _name, CMD_PTR)))
  52
  53 __printf_2_3 void (*para_log)(int, const char*, ...) = daemon_log;
  54 /** define the array containing all supported audio formats */
  55 const char *audio_formats[] = {AUDIOD_AUDIO_FORMAT_ARRAY NULL};
  56
  57 /** Defines how audiod handles one supported audio format. */
  58 struct audio_format_info {
  59         /** the receiver for this audio format */
  60         int receiver_num;
  61         /** Parsed receiver command line. */
  62         struct lls_parse_result *receiver_lpr;
  63         /** the number of filters that should be activated for this audio format */
  64         unsigned int num_filters;
  65         /** Array of filter numbers to be activated. */
  66         unsigned *filter_nums;
  67         /** Pointer to the array of filter configurations. */
  68         void **filter_conf;
  69         /** Parsed filter command line, one parse result per filter. */
  70         struct lls_parse_result **filter_lpr;
  71         /** the number of filters that should be activated for this audio format */
  72         unsigned int num_writers;
  73         /** Array of writer IDs to be activated. */
  74         int *wids;
  75         /** Parsed writer command line(s) */
  76         struct lls_parse_result **writer_lpr;
  77         /** do not start receiver/filters/writer before this time */
  78         struct timeval restart_barrier;
  79 };
  80
  81 /* Describes one instance of a receiver-filter-writer chain. */
  82 struct slot_info {
  83         /* Number of the audio format in this slot. */
  84         int format;
  85         /* The stream_start status item announced by para_server.  */
  86         struct timeval server_stream_start;
  87         /* The offset status item announced by para_server. */
  88         unsigned offset_seconds;
  89         /* The seconds_total status item announced by para_server. */
  90         unsigned seconds_total;
  91         /* The receiver info associated with this slot. */
  92         struct receiver_node *receiver_node;
  93         /* The array of filter nodes. */
  94         struct filter_node *fns;
  95         /* The array of writers attached to the last filter. */
  96         struct writer_node *wns;
  97 };
  98
  99 #define RECEIVER_CMD(_a) lls_cmd((_a)->receiver_num, recv_cmd_suite)
 100 #define RECEIVER(_a) ((const struct receiver *)lls_user_data(RECEIVER_CMD(_a)))
 101
 102 /** Maximal number of simultaneous instances. */
 103 #define MAX_STREAM_SLOTS 5
 104
 105 /** Iterate over all slots. */
 106 #define FOR_EACH_SLOT(_slot) for (_slot = 0; _slot < MAX_STREAM_SLOTS; _slot++)
 107
 108 /**
 109  * para_audiod uses \p MAX_STREAM_SLOTS different slots, each of which may
 110  * be associated with a receiver/filter/writer triple. This array holds all
 111  * information on the status of these slots.
 112  */
 113 struct slot_info slot[MAX_STREAM_SLOTS];
 114
 115 /** The vss status flags audiod is interested in. */
 116 enum vss_status_flags {
 117         /** Whether the 'N' flag is set. */
 118         VSS_STATUS_FLAG_NEXT = 1,
 119         /** The 'P' flag is set. */
 120         VSS_STATUS_FLAG_PLAYING = 2,
 121 };
 122
 123 /**
 124  * The scheduler instance of para_audiod.
 125  *
 126  * This is needed also in audiod_command.c (for the tasks command), so it can
 127  * not be made static.
 128  */
 129 struct sched sched = {.max_fileno = 0};
 130
 131 /* The task for obtaining para_server's status (para_client stat). */
 132 struct status_task {
 133         /** The associated task structure of audiod. */
 134         struct task *task;
 135         /** Client data associated with the stat task. */
 136         struct client_task *ct;
 137         /** Do not restart client command until this time. */
 138         struct timeval restart_barrier;
 139         /** Last time we received status data from para_server. */
 140         struct timeval last_status_read;
 141         size_t min_iqs;
 142         /** The offset value announced by para_server. */
 143         int offset_seconds;
 144         /** The length of the current audio file as announced by para_server. */
 145         int length_seconds;
 146         /** The start of the current stream from the view of para_server. */
 147         struct timeval server_stream_start;
 148         /** The average time deviation between para_server and para_audiod. */
 149         struct timeval sa_time_diff;
 150         /** Whether client time is ahead of server time. */
 151         int sa_time_diff_sign;
 152         /** The 'P' and the 'N' flags as announced by para_server. */
 153         enum vss_status_flags vss_status;
 154         /** Number of times the clock difference is to be checked. */
 155         unsigned clock_diff_count;
 156         /** When to start the next check for clock difference. */
 157         struct timeval clock_diff_barrier;
 158         /** Number of the audio format as announced by para_server. */
 159         int current_audio_format_num;
 160         /* The status task btrn is the child of the client task. */
 161         struct btr_node *btrn;
 162 };
 163
 164 /** The array of status items sent by para_server. */
 165 char *stat_item_values[NUM_STAT_ITEMS] = {NULL};
 166
 167 /**
 168  * The current mode of operation (AUDIOD_OFF, AUDIOD_ON or AUDIOD_STANDBY).
 169  * Set by the on/off/cycle commands.
 170  */
 171 int audiod_status = AUDIOD_ON;
 172
 173 static char *socket_name;
 174 static struct audio_format_info afi[NUM_AUDIO_FORMATS];
 175 static struct signal_task *signal_task;
 176 static struct status_task status_task_struct;
 177 static uid_t *uid_whitelist;
 178
 179 /**
 180  * The task that calls the status command of para_server.
 181  *
 182  * \sa \ref struct status_task.
 183  */
 184 static struct status_task *stat_task = &status_task_struct;
 185
 186 struct command_task {
 187         /** The local listening socket. */
 188         int fd;
 189         /** The associated task structure. */
 190         struct task *task;
 191 };
 192
 193 /** Iterate over all supported audio formats. */
 194 #define FOR_EACH_AUDIO_FORMAT(af) for (af = 0; af < NUM_AUDIO_FORMATS; af++)
 195
 196 /**
 197  * Get the audio format number.
 198  *
 199  * \param name The name of the audio format.
 200  *
 201  * \return The audio format number on success, -E_UNSUPPORTED_AUDIO_FORMAT if
 202  * \a name is not a supported audio format.
 203  */
 204 static int get_audio_format_num(const char *name)
 205 {
 206         int i;
 207
 208         while (para_isspace(*name))
 209                 name++;
 210         FOR_EACH_AUDIO_FORMAT(i)
 211                 if (!strcmp(name, audio_formats[i]))
 212                         return i;
 213         return -E_UNSUPPORTED_AUDIO_FORMAT;
 214 }
 215
 216 /**
 217  * Return the flags for the \a decoder_flags status item.
 218  *
 219  * Allocates a string which contains one octal digit per slot.  Bit zero (value
 220  * 1) is set if a receiver is active. Bit one (value 2) and bit three (value 4)
 221  * have the analogous meaning for filter and writer, respectively.
 222  *
 223  * \return String that must be freed by the caller.
 224  */
 225 __malloc char *audiod_get_decoder_flags(void)
 226 {
 227         int i;
 228         char flags[MAX_STREAM_SLOTS + 1];
 229
 230         FOR_EACH_SLOT(i) {
 231                 struct slot_info *s = &slot[i];
 232                 char flag = '0';
 233                 if (s->receiver_node)
 234                         flag += 1;
 235                 if (s->fns)
 236                         flag += 2;
 237                 if (s->wns)
 238                         flag += 4;
 239                 flags[i] = flag;
 240         }
 241         flags[MAX_STREAM_SLOTS] = '\0';
 242         return para_strdup(flags);
 243 }
 244
 245 static int get_matching_audio_format_nums(const char *re)
 246 {
 247         int i, ret;
 248         regex_t preg;
 249
 250         ret = para_regcomp(&preg, re, REG_EXTENDED | REG_NOSUB);
 251         if (ret < 0)
 252                 return ret;
 253         ret = 0;
 254         FOR_EACH_AUDIO_FORMAT(i)
 255                 if (regexec(&preg, audio_formats[i], 0, NULL, 0) != REG_NOMATCH)
 256                         ret |= (1 << i);
 257         regfree(&preg);
 258         return ret;
 259 }
 260
 261 static int get_play_time_slot_num(void)
 262 {
 263         int i, oldest_slot = -1;
 264         struct timeval oldest_wstime = {0, 0};
 265
 266         FOR_EACH_SLOT(i) {
 267                 struct slot_info *s = &slot[i];
 268                 struct timeval wstime;
 269                 if (!s->wns || !s->wns[0].btrn)
 270                         continue;
 271                 btr_get_node_start(s->wns[0].btrn, &wstime);
 272                 if (oldest_slot >= 0 && tv_diff(&wstime, &oldest_wstime, NULL) > 0)
 273                         continue;
 274                 oldest_wstime = wstime;
 275                 oldest_slot = i;
 276         }
 277         return oldest_slot;
 278 }
 279
 280 /**
 281  * Compute the play time based on information of the current slot.
 282  *
 283  * This computes a string of the form "0:07 [3:33] (3%/3:40)" using information
 284  * from the status items received from para_server and the start time of the
 285  * (first) writer of the current slot.
 286  *
 287  * It has to take into account that the stream was probably not started at
 288  * the beginning of the file, that the clock between the server and the client
 289  * host may differ and that playback of the stream was delayed, e.g. because
 290  * the prebuffer filter is used in the filter configuration.
 291  *
 292  * If no writer is active, for example because para_audiod runs in standby
 293  * mode, an approximation based only on the status items is computed and the
 294  * returned string is prefixed with "~".
 295  *
 296  * \return A string that must be freed by the caller.
 297  */
 298 char *get_time_string(void)
 299 {
 300         int ret, seconds = 0, length = stat_task->length_seconds;
 301         struct timeval *tmp, sum, sss, /* server stream start */
 302                 rstime, /* receiver start time */
 303                 wstime, /* writer start time */
 304                 wtime, /* now - writer start */
 305                 rskip; /* receiver start - sss */
 306         int slot_num = get_play_time_slot_num();
 307         struct slot_info *s = slot_num < 0? NULL : &slot[slot_num];
 308         bool writer_active = s && s->wns && s->wns[0].btrn;
 309         char *msg;
 310
 311         if (audiod_status == AUDIOD_OFF)
 312                 goto empty;
 313         if (stat_task->server_stream_start.tv_sec == 0) {
 314                 if (stat_task->vss_status & VSS_STATUS_FLAG_PLAYING)
 315                         goto out; /* server is about to change file */
 316                 if (length > 0) /* paused */
 317                         return NULL;
 318                 goto empty; /* stopped */
 319         }
 320         /*
 321          * Valid status items and playing, set length and tmp to the stream
 322          * start. We use the writer start time from the slot info and fall back
 323          * to the info from current status items if no writer is active yet.
 324          */
 325         tmp = &stat_task->server_stream_start;
 326         if (writer_active) {
 327                 btr_get_node_start(s->wns[0].btrn, &wstime);
 328                 if (wstime.tv_sec != 0) { /* writer wrote something */
 329                         if (s->server_stream_start.tv_sec == 0) {
 330                                 /* copy status info to slot */
 331                                 s->server_stream_start = stat_task->server_stream_start;
 332                                 s->offset_seconds = stat_task->offset_seconds;
 333                                 s->seconds_total = stat_task->length_seconds;
 334                         }
 335                         length = s->seconds_total;
 336                         tmp = &s->server_stream_start;
 337                 }
 338         }
 339         if (stat_task->sa_time_diff_sign > 0)
 340                 tv_diff(tmp, &stat_task->sa_time_diff, &sss);
 341         else
 342                 tv_add(tmp, &stat_task->sa_time_diff, &sss);
 343         if (!writer_active) {
 344                 struct timeval diff;
 345                 tv_diff(now, &sss, &diff);
 346                 seconds = diff.tv_sec + stat_task->offset_seconds;
 347                 goto out;
 348         }
 349         tv_diff(now, &wstime, &wtime);
 350         //PARA_CRIT_LOG("offset %d\n", s->offset_seconds);
 351         seconds = s->offset_seconds;
 352         if (s->receiver_node->btrn) {
 353                 btr_get_node_start(s->receiver_node->btrn, &rstime);
 354                 ret = tv_diff(&rstime, &sss, &rskip);
 355                 if (ret > 0 && rskip.tv_sec > 2) {
 356                         /* audiod was started in the middle of the stream */
 357                         tv_add(&wtime, &rskip, &sum);
 358                         seconds += sum.tv_sec;
 359                 } else
 360                         seconds += wtime.tv_sec;
 361         } else
 362                 seconds += wtime.tv_sec;
 363 out:
 364         seconds = PARA_MIN(seconds, length);
 365         seconds = PARA_MAX(seconds, 0);
 366         msg = make_message(
 367                 "%s%d:%02d [%d:%02d] (%d%%/%d:%02d)",
 368                 s? "" : "~",
 369                 seconds / 60,
 370                 seconds % 60,
 371                 (length - seconds) / 60,
 372                 (length - seconds) % 60,
 373                 length? (seconds * 100 + length / 2) / length : 0,
 374                 length / 60,
 375                 length % 60
 376         );
 377         //PARA_DEBUG_LOG("slot %d: %s\n", slot_num, msg);
 378         return msg;
 379 empty:
 380         return para_strdup(NULL);
 381 }
 382
 383 static void parse_config_or_die(void)
 384 {
 385         int ret;
 386         char *cf, *errctx = NULL;
 387         void *map;
 388         size_t sz;
 389
 390         if (OPT_GIVEN(CONFIG_FILE))
 391                 cf = para_strdup(OPT_STRING_VAL(CONFIG_FILE));
 392         else {
 393                 char *home = para_homedir();
 394                 cf = make_message("%s/.paraslash/audiod.conf", home);
 395                 free(home);
 396         }
 397         ret = mmap_full_file(cf, O_RDONLY, &map, &sz, NULL);
 398         if (ret < 0) {
 399                 if (ret != -E_EMPTY && ret != -ERRNO_TO_PARA_ERROR(ENOENT))
 400                         goto free_cf;
 401                 if (ret == -ERRNO_TO_PARA_ERROR(ENOENT) && OPT_GIVEN(CONFIG_FILE))
 402                         goto free_cf;
 403         } else {
 404                 int cf_argc;
 405                 char **cf_argv;
 406                 struct lls_parse_result *cf_lpr, *merged_lpr;
 407                 ret = lls(lls_convert_config(map, sz, NULL, &cf_argv, &errctx));
 408                 para_munmap(map, sz);
 409                 if (ret < 0)
 410                         goto free_cf;
 411                 cf_argc = ret;
 412                 ret = lls(lls_parse(cf_argc, cf_argv, CMD_PTR, &cf_lpr, &errctx));
 413                 lls_free_argv(cf_argv);
 414                 if (ret < 0)
 415                         goto free_cf;
 416                 ret = lls(lls_merge(lpr, cf_lpr, CMD_PTR, &merged_lpr,
 417                         &errctx));
 418                 lls_free_parse_result(cf_lpr, CMD_PTR);
 419                 if (ret < 0)
 420                         goto free_cf;
 421                 lls_free_parse_result(lpr, CMD_PTR);
 422                 lpr = merged_lpr;
 423         }
 424         daemon_set_loglevel(ENUM_STRING_VAL(LOGLEVEL));
 425         if (OPT_GIVEN(USER_ALLOW)) {
 426                 uint32_t n = OPT_GIVEN(USER_ALLOW);
 427                 int i;
 428
 429                 uid_whitelist = para_malloc(n * sizeof(uid_t));
 430                 for (i = 0; i < n; i++) {
 431                         const char *arg = lls_string_val(i,
 432                                 OPT_RESULT(USER_ALLOW));
 433                         int32_t val;
 434                         struct passwd *pw;
 435                         ret = para_atoi32(arg, &val);
 436                         if (ret >= 0) {
 437                                 uid_whitelist[i] = val;
 438                                 continue;
 439                         }
 440                         errno = 0; /* see getpwnam(3) */
 441                         pw = getpwnam(arg);
 442                         if (!pw) {
 443                                 PARA_EMERG_LOG("invalid username: %s\n", arg);
 444                                 free(uid_whitelist);
 445                                 goto free_cf;
 446                         }
 447                         uid_whitelist[i] = pw->pw_uid;
 448                 }
 449         }
 450         ret = 0;
 451 free_cf:
 452         free(cf);
 453         if (ret < 0) {
 454                 if (errctx)
 455                         PARA_ERROR_LOG("%s\n", errctx);
 456                 free(errctx);
 457                 lls_free_parse_result(lpr, CMD_PTR);
 458                 PARA_EMERG_LOG("%s\n", para_strerror(-ret));
 459                 exit(EXIT_FAILURE);
 460         }
 461 }
 462
 463 static void setup_signal_handling(void)
 464 {
 465         signal_task = signal_init_or_die();
 466         para_install_sighandler(SIGINT);
 467         para_install_sighandler(SIGTERM);
 468         para_install_sighandler(SIGHUP);
 469         para_sigaction(SIGPIPE, SIG_IGN);
 470 }
 471
 472 static void clear_slot(int slot_num)
 473 {
 474         struct slot_info *s = &slot[slot_num];
 475
 476         PARA_INFO_LOG("clearing slot %d\n", slot_num);
 477         memset(s, 0, sizeof(struct slot_info));
 478         s->format = -1;
 479 }
 480
 481 static void close_receiver(int slot_num)
 482 {
 483         struct slot_info *s = &slot[slot_num];
 484         struct audio_format_info *a;
 485
 486         if (s->format < 0 || !s->receiver_node)
 487                 return;
 488         a = &afi[s->format];
 489         PARA_NOTICE_LOG("closing %s receiver in slot %d\n",
 490                 audio_formats[s->format], slot_num);
 491         RECEIVER(a)->close(s->receiver_node);
 492         btr_remove_node(&s->receiver_node->btrn);
 493         task_reap(&s->receiver_node->task);
 494         free(s->receiver_node);
 495         s->receiver_node = NULL;
 496         stat_task->current_audio_format_num = -1;
 497         tv_add(now, &(struct timeval)EMBRACE(0, 200 * 1000),
 498                 &a->restart_barrier);
 499 }
 500
 501 static void writer_cleanup(struct writer_node *wn)
 502 {
 503         if (!wn)
 504                 return;
 505         PARA_INFO_LOG("closing %s\n", writer_name(wn->wid));
 506         writer_get(wn->wid)->close(wn);
 507         btr_remove_node(&wn->btrn);
 508         task_reap(&wn->task);
 509 }
 510
 511 static void close_writers(struct slot_info *s)
 512 {
 513         struct audio_format_info *a;
 514         int i;
 515
 516         if (s->format < 0)
 517                 return;
 518         assert(s->wns);
 519         a = afi + s->format;
 520         if (a->num_writers == 0)
 521                 writer_cleanup(s->wns);
 522         else {
 523                 for (i = 0; i < a->num_writers; i++)
 524                         writer_cleanup(s->wns + i);
 525         }
 526         free(s->wns);
 527         s->wns = NULL;
 528 }
 529
 530 static void close_filters(struct slot_info *s)
 531 {
 532         int i;
 533         struct audio_format_info *a = afi + s->format;
 534         if (a->num_filters == 0)
 535                 return;
 536         for (i = a->num_filters - 1; i >= 0; i--) {
 537                 struct filter_node *fn = s->fns + i;
 538                 const struct filter *f;
 539
 540                 if (!fn)
 541                         continue;
 542                 f = filter_get(fn->filter_num);
 543                 if (f->close)
 544                         f->close(fn);
 545                 btr_remove_node(&fn->btrn);
 546                 task_reap(&fn->task);
 547         }
 548         free(s->fns);
 549         s->fns = NULL;
 550 }
 551
 552 static void notify_receivers(int error)
 553 {
 554         int i;
 555
 556         FOR_EACH_SLOT(i) {
 557                 struct slot_info *s = slot + i;
 558                 if (s->format < 0)
 559                         continue;
 560                 if (!s->receiver_node)
 561                         continue;
 562                 task_notify(s->receiver_node->task, error);
 563         }
 564 }
 565
 566 static int get_empty_slot(void)
 567 {
 568         int i;
 569         struct slot_info *s;
 570
 571         FOR_EACH_SLOT(i) {
 572                 s = &slot[i];
 573                 if (s->format < 0) {
 574                         clear_slot(i);
 575                         return i;
 576                 }
 577                 if (s->wns || s->receiver_node || s->fns)
 578                         continue;
 579                 clear_slot(i);
 580                 return i;
 581         }
 582         return -E_NO_MORE_SLOTS;
 583 }
 584
 585 static void open_filters(struct slot_info *s)
 586 {
 587         struct audio_format_info *a = afi + s->format;
 588         struct filter_node *fn;
 589         int nf = a->num_filters;
 590         struct btr_node *parent;
 591         int i;
 592
 593         if (nf == 0)
 594                 return;
 595         PARA_INFO_LOG("opening %s filters\n", audio_formats[s->format]);
 596         assert(s->fns == NULL);
 597         s->fns = para_calloc(nf * sizeof(struct filter_node));
 598         parent = s->receiver_node->btrn;
 599         for (i = 0; i < nf; i++) {
 600                 char buf[20];
 601                 const char *name;
 602                 const struct filter *f = filter_get(a->filter_nums[i]);
 603                 fn = s->fns + i;
 604                 fn->filter_num = a->filter_nums[i];
 605                 fn->conf = a->filter_conf[i];
 606                 fn->lpr = a->filter_lpr[i];
 607                 name = filter_name(fn->filter_num);
 608                 fn->btrn = btr_new_node(&(struct btr_node_description)
 609                         EMBRACE(.name = name, .parent = parent,
 610                                 .handler = f->execute, .context = fn));
 611
 612                 if (f->open)
 613                         f->open(fn);
 614                 sprintf(buf, "%s (slot %d)", name, (int)(s - slot));
 615                 fn->task = task_register(&(struct task_info) {
 616                         .name = buf,
 617                         .pre_select = f->pre_select,
 618                         .post_select = f->post_select,
 619                         .context = fn,
 620                 }, &sched);
 621                 parent = fn->btrn;
 622                 PARA_NOTICE_LOG("%s filter %d/%d (%s) started in slot %d\n",
 623                         audio_formats[s->format], i,  nf, name, (int)(s - slot));
 624         }
 625 }
 626
 627 static void open_writers(struct slot_info *s)
 628 {
 629         int i;
 630         struct audio_format_info *a = afi + s->format;
 631         struct writer_node *wn;
 632         struct btr_node *parent = s->fns[a->num_filters - 1].btrn;
 633
 634         assert(s->wns == NULL);
 635         s->wns = para_calloc(PARA_MAX(1U, a->num_writers)
 636                 * sizeof(struct writer_node));
 637         for (i = 0; i < a->num_writers; i++) {
 638                 wn = s->wns + i;
 639                 wn->wid = a->wids[i];
 640                 wn->lpr = a->writer_lpr[i];
 641                 register_writer_node(wn, parent, &sched);
 642                 PARA_NOTICE_LOG("%s writer started in slot %d\n",
 643                         writer_name(a->wids[i]), (int)(s - slot));
 644         }
 645 }
 646
 647 /* returns slot num on success */
 648 static int open_receiver(int format)
 649 {
 650         struct audio_format_info *a = &afi[format];
 651         struct slot_info *s;
 652         int ret, slot_num;
 653         const struct receiver *r = RECEIVER(a);
 654         const char *name = lls_command_name(RECEIVER_CMD(a));
 655         struct receiver_node *rn;
 656
 657         tv_add(now, &(struct timeval)EMBRACE(2, 0), &a->restart_barrier);
 658         ret = get_empty_slot();
 659         if (ret < 0)
 660                 return ret;
 661         slot_num = ret;
 662         rn = para_calloc(sizeof(*rn));
 663         rn->receiver = r;
 664         rn->lpr = a->receiver_lpr;
 665         rn->btrn = btr_new_node(&(struct btr_node_description)
 666                 EMBRACE(.name = name, .context = rn));
 667         ret = r->open(rn);
 668         if (ret < 0) {
 669                 PARA_ERROR_LOG("could not open %s receiver\n", name);
 670                 btr_remove_node(&rn->btrn);
 671                 free(rn);
 672                 return ret;
 673         }
 674         s = &slot[slot_num];
 675         s->format = format;
 676         s->receiver_node = rn;
 677         PARA_NOTICE_LOG("started %s: %s receiver in slot %d\n",
 678                 audio_formats[format], name, slot_num);
 679         rn->task = task_register(&(struct task_info) {
 680                 .name = name,
 681                 .pre_select = r->pre_select,
 682                 .post_select = r->post_select,
 683                 .context = rn,
 684         }, &sched);
 685         return slot_num;
 686 }
 687
 688 static bool receiver_running(void)
 689 {
 690         int i;
 691         long unsigned ss1 = stat_task->server_stream_start.tv_sec;
 692
 693         FOR_EACH_SLOT(i) {
 694                 struct slot_info *s = &slot[i];
 695                 long unsigned ss2 = s->server_stream_start.tv_sec;
 696
 697                 if (!s->receiver_node)
 698                         continue;
 699                 if (task_status(s->receiver_node->task) >= 0)
 700                         return true;
 701                 if (ss1 == ss2)
 702                         return true;
 703         }
 704         return false;
 705 }
 706
 707 /**
 708  * Return the root node of the current buffer tree.
 709  *
 710  * This is only used for stream grabbing.
 711  *
 712  * \return \p NULL if no slot is currently active. If more than one buffer tree
 713  * exists, the node corresponding to the most recently started receiver is
 714  * returned.
 715  */
 716 struct btr_node *audiod_get_btr_root(void)
 717 {
 718         int i, newest_slot = -1;
 719         struct timeval newest_rstime = {0, 0};
 720
 721         FOR_EACH_SLOT(i) {
 722                 struct slot_info *s = &slot[i];
 723                 struct timeval rstime;
 724                 if (!s->receiver_node)
 725                         continue;
 726                 if (task_status(s->receiver_node->task) < 0)
 727                         continue;
 728                 btr_get_node_start(s->receiver_node->btrn, &rstime);
 729                 if (newest_slot >= 0 && tv_diff(&rstime, &newest_rstime, NULL) < 0)
 730                         continue;
 731                 newest_rstime = rstime;
 732                 newest_slot = i;
 733         }
 734         if (newest_slot == -1)
 735                 return NULL;
 736         return slot[newest_slot].receiver_node->btrn;
 737 }
 738
 739 /* whether a new instance of a decoder should be started. */
 740 static bool must_start_decoder(void)
 741 {
 742         int cafn = stat_task->current_audio_format_num;
 743         unsigned vs = stat_task->vss_status;
 744
 745         if (audiod_status != AUDIOD_ON)
 746                 return false;
 747         if (cafn < 0)
 748                 return false;
 749         if (!stat_task->ct)
 750                 return false;
 751         if (vs & VSS_STATUS_FLAG_NEXT)
 752                 return false;
 753         if (!(vs & VSS_STATUS_FLAG_PLAYING))
 754                 return false;
 755         if (receiver_running())
 756                 return false;
 757         if (tv_diff(now, &afi[cafn].restart_barrier, NULL) < 0)
 758                 return false;
 759         return true;
 760 }
 761
 762 static void compute_time_diff(const struct timeval *status_time)
 763 {
 764         struct timeval tmp, diff;
 765         static unsigned count;
 766         int sign, sa_time_diff_sign = stat_task->sa_time_diff_sign;
 767         const struct timeval max_deviation = {0, 500 * 1000};
 768         const int time_smooth = 5;
 769
 770         sign = tv_diff(status_time, now, &diff);
 771 //              PARA_NOTICE_LOG("%s: sign = %i, sa_time_diff_sign = %i\n", __func__,
 772 //                      sign, sa_time_diff_sign);
 773         if (!count) {
 774                 sa_time_diff_sign = sign;
 775                 stat_task->sa_time_diff = diff;
 776                 count++;
 777                 goto out;
 778         }
 779         if (count > 5) {
 780                 int s = tv_diff(&diff, &stat_task->sa_time_diff, &tmp);
 781                 if (tv_diff(&max_deviation, &tmp, NULL) < 0)
 782                         PARA_WARNING_LOG("time diff jump: %lums\n",
 783                                 s * tv2ms(&tmp));
 784         }
 785         count++;
 786         sa_time_diff_sign = tv_convex_combination(
 787                 sa_time_diff_sign * time_smooth, &stat_task->sa_time_diff,
 788                 count > 10? sign : sign * time_smooth, &diff,
 789                 &tmp);
 790         stat_task->sa_time_diff = tmp;
 791         PARA_INFO_LOG("time diff (cur/avg): %s%lums/%s%lums\n",
 792                 sign < 0? "-" : "+",
 793                 tv2ms(&diff),
 794                 sa_time_diff_sign < 0? "-" : "+",
 795                 tv2ms(&stat_task->sa_time_diff)
 796         );
 797 out:
 798         stat_task->sa_time_diff_sign = sa_time_diff_sign;
 799 }
 800
 801 static int update_item(int itemnum, char *buf)
 802 {
 803         long unsigned sec, usec;
 804
 805         if (stat_task->clock_diff_count && itemnum != SI_current_time)
 806                 return 1;
 807         free(stat_item_values[itemnum]);
 808         stat_item_values[itemnum] = para_strdup(buf);
 809         stat_client_write_item(itemnum);
 810         switch (itemnum) {
 811         case SI_status_flags:
 812                 stat_task->vss_status = 0;
 813                 if (strchr(buf, 'N'))
 814                         stat_task->vss_status |= VSS_STATUS_FLAG_NEXT;
 815                 if (strchr(buf, 'P'))
 816                         stat_task->vss_status |= VSS_STATUS_FLAG_PLAYING;
 817                 break;
 818         case SI_offset:
 819                 stat_task->offset_seconds = atoi(buf);
 820                 break;
 821         case SI_seconds_total:
 822                 stat_task->length_seconds = atoi(buf);
 823                 break;
 824         case SI_stream_start:
 825                 if (sscanf(buf, "%lu.%lu", &sec, &usec) == 2) {
 826                         stat_task->server_stream_start.tv_sec = sec;
 827                         stat_task->server_stream_start.tv_usec = usec;
 828                 }
 829                 break;
 830         case SI_current_time:
 831                 if (sscanf(buf, "%lu.%lu", &sec, &usec) == 2) {
 832                         struct timeval tv = {sec, usec};
 833                         compute_time_diff(&tv);
 834                 }
 835                 break;
 836         case SI_format:
 837                 stat_task->current_audio_format_num
 838                         = get_audio_format_num(buf);
 839         }
 840         return 1;
 841 }
 842
 843 static int parse_stream_command(const char *txt, const char **cmd)
 844 {
 845         int ret, len;
 846         char *re, *p = strchr(txt, ':');
 847
 848         if (!p)
 849                 return -E_MISSING_COLON;
 850         *cmd = p + 1;
 851         len = p - txt;
 852         re = malloc(len + 1);
 853         strncpy(re, txt, len);
 854         re[len] = '\0';
 855         ret = get_matching_audio_format_nums(re);
 856         free(re);
 857         return ret;
 858 }
 859
 860 static int add_filter(int format, const char *cmdline)
 861 {
 862         struct audio_format_info *a = &afi[format];
 863         int filter_num, nf = a->num_filters;
 864         void *cfg;
 865         struct lls_parse_result *flpr;
 866
 867         filter_num = filter_setup(cmdline, &cfg, &flpr);
 868         a->filter_lpr = para_realloc(a->filter_lpr,
 869                 (nf + 1) * sizeof(flpr));
 870         a->filter_conf = para_realloc(a->filter_conf,
 871                 (nf + 1) * sizeof(void *));
 872         a->filter_nums = para_realloc(a->filter_nums,
 873                 (nf + 1) * sizeof(unsigned));
 874
 875         a->filter_nums[nf] = filter_num;
 876         a->filter_conf[nf] = cfg;
 877         a->filter_lpr[nf] = flpr;
 878         a->num_filters++;
 879         PARA_INFO_LOG("%s filter %d: %s\n", audio_formats[format], nf,
 880                 filter_name(filter_num));
 881         return filter_num;
 882 }
 883
 884 static int parse_writer_args(void)
 885 {
 886         int i, ret;
 887         const char *cmd;
 888         struct audio_format_info *a;
 889
 890         for (i = 0; i < OPT_GIVEN(WRITER); i++) {
 891                 int j, nw, af_mask;
 892
 893                 ret = parse_stream_command(lls_string_val(i,
 894                         OPT_RESULT(WRITER)), &cmd);
 895                 if (ret < 0)
 896                         return ret;
 897                 af_mask = ret;
 898                 FOR_EACH_AUDIO_FORMAT(j) {
 899                         a = afi + j;
 900                         if ((af_mask & (1 << j)) == 0) /* no match */
 901                                 continue;
 902                         nw = a->num_writers;
 903                         a->wids = para_realloc(a->wids, (nw + 1) * sizeof(int));
 904                         a->writer_lpr = para_realloc(a->writer_lpr,
 905                                 (nw + 1) * sizeof(struct lls_parse_result *));
 906                         a->wids[nw] = check_writer_arg_or_die(cmd,
 907                                 a->writer_lpr + nw);
 908                         PARA_INFO_LOG("%s writer #%d: %s\n", audio_formats[j],
 909                                 nw, writer_name(a->wids[nw]));
 910                         a->num_writers++;
 911                 }
 912         }
 913         /* Use default writer for audio formats which are not yet set up. */
 914         FOR_EACH_AUDIO_FORMAT(i) {
 915                 a = afi + i;
 916                 if (a->num_writers > 0)
 917                         continue; /* already set up */
 918                 a->num_writers = 1;
 919                 a->wids = para_malloc(sizeof(int));
 920                 a->writer_lpr = para_malloc(sizeof(struct lls_parse_result *));
 921                 a->wids[0] = check_writer_arg_or_die(NULL, a->writer_lpr);
 922                 PARA_INFO_LOG("%s writer: %s (default)\n", audio_formats[i],
 923                         writer_name(a->wids[0]));
 924         }
 925         return 1;
 926 }
 927
 928 static int parse_receiver_args(void)
 929 {
 930         int i, ret;
 931         const char *arg;
 932         struct audio_format_info *a;
 933
 934         FOR_EACH_AUDIO_FORMAT(i)
 935                 afi[i].receiver_num = -1;
 936         for (i = OPT_GIVEN(RECEIVER) - 1; i >= 0; i--) {
 937                 int j, af_mask;
 938
 939                 ret = parse_stream_command(lls_string_val(i,
 940                         OPT_RESULT(RECEIVER)), &arg);
 941                 if (ret < 0)
 942                         goto out;
 943                 af_mask = ret;
 944                 FOR_EACH_AUDIO_FORMAT(j) {
 945                         a = afi + j;
 946                         if ((af_mask & (1 << j)) == 0) /* no match */
 947                                 continue;
 948                         /*
 949                          * If multiple receivers are given for this audio format, the
 950                          * last one wins and we have to free the previous receiver
 951                          * config here. Since we are iterating backwards, the winning
 952                          * receiver arg is in fact the first one given.
 953                          */
 954                         lls_free_parse_result(a->receiver_lpr, RECEIVER_CMD(a));
 955                         a->receiver_num = check_receiver_arg(arg, &a->receiver_lpr);
 956                 }
 957         }
 958         /*
 959          * Use the default receiver for those audio formats for which no
 960          * receiver was specified.
 961          */
 962         FOR_EACH_AUDIO_FORMAT(i) {
 963                 a = afi + i;
 964                 if (a->receiver_num >= 0)
 965                         continue;
 966                 a->receiver_num = check_receiver_arg(NULL, &a->receiver_lpr);
 967         }
 968         FOR_EACH_AUDIO_FORMAT(i) {
 969                 a = afi + i;
 970                 PARA_INFO_LOG("receiving %s streams via %s receiver\n",
 971                         audio_formats[i], lls_command_name(RECEIVER_CMD(a)));
 972         }
 973         ret = 1;
 974 out:
 975         return ret;
 976 }
 977
 978 static int init_default_filters(void)
 979 {
 980         int i, ret = 1;
 981
 982         FOR_EACH_AUDIO_FORMAT(i) {
 983                 struct audio_format_info *a = &afi[i];
 984                 const char *name = lls_command_name(RECEIVER_CMD(a));
 985                 char *tmp;
 986                 int j;
 987
 988                 if (a->num_filters)
 989                         continue; /* no default -- nothing to to */
 990                 /*
 991                  * udp and dccp streams are fec-encoded, so add fecdec as the
 992                  * first filter.
 993                  */
 994                 if (strcmp(name, "udp") == 0 || strcmp(name, "dccp") == 0) {
 995                         tmp = para_strdup("fecdec");
 996                         add_filter(i, tmp);
 997                         free(tmp);
 998                         if (ret < 0)
 999                                 goto out;
1000                 }
1001                 /* add "dec" to audio format name */
1002                 tmp = make_message("%sdec", audio_formats[i]);
1003                 for (j = 1; filter_get(j); j++)
1004                         if (!strcmp(tmp, filter_name(j)))
1005                                 break;
1006                 free(tmp);
1007                 ret = -E_UNSUPPORTED_FILTER;
1008                 if (!filter_get(j))
1009                         goto out;
1010                 tmp = para_strdup(filter_name(j));
1011                 ret = add_filter(i, tmp);
1012                 free(tmp);
1013                 if (ret < 0)
1014                         goto out;
1015                 PARA_INFO_LOG("%s -> default filter: %s\n", audio_formats[i],
1016                         filter_name(j));
1017         }
1018 out:
1019         return ret;
1020 }
1021
1022 static int parse_filter_args(void)
1023 {
1024         int i, j, ret, af_mask, num_matches;
1025
1026         for (i = 0; i < OPT_GIVEN(FILTER); i++) {
1027                 const char *arg;
1028                 ret = parse_stream_command(lls_string_val(i,
1029                         OPT_RESULT(FILTER)), &arg);
1030                 if (ret < 0)
1031                         goto out;
1032                 af_mask = ret;
1033                 num_matches = 0;
1034                 FOR_EACH_AUDIO_FORMAT(j) {
1035                         if ((af_mask & (1 << j)) == 0) /* no match */
1036                                 continue;
1037                         ret = add_filter(j, arg);
1038                         if (ret < 0)
1039                                 goto out;
1040                         num_matches++;
1041                 }
1042                 if (num_matches == 0)
1043                         PARA_WARNING_LOG("ignoring filter spec: %s\n",
1044                                 lls_string_val(i, OPT_RESULT(FILTER)));
1045         }
1046         ret = init_default_filters(); /* use default values for the rest */
1047 out:
1048         return ret;
1049 }
1050
1051 static int parse_stream_args(void)
1052 {
1053         int ret;
1054
1055         ret = parse_receiver_args();
1056         if (ret < 0)
1057                 return ret;
1058         ret = parse_filter_args();
1059         if (ret < 0)
1060                 return ret;
1061         ret = parse_writer_args();
1062         if (ret < 0)
1063                 return ret;
1064         return 1;
1065 }
1066
1067 /* does not unlink socket on errors */
1068 static void init_local_socket(struct command_task *ct)
1069 {
1070         if (OPT_GIVEN(SOCKET))
1071                 socket_name = para_strdup(OPT_STRING_VAL(SOCKET));
1072         else {
1073                 char *hn = para_hostname();
1074                 socket_name = make_message("/var/paraslash/audiod_socket.%s",
1075                         hn);
1076                 free(hn);
1077         }
1078         PARA_NOTICE_LOG("local socket: %s\n", socket_name);
1079         if (OPT_GIVEN(FORCE))
1080                 unlink(socket_name);
1081         ct->fd = create_local_socket(socket_name);
1082         if (ct->fd >= 0)
1083                 return;
1084         PARA_EMERG_LOG("%s\n", para_strerror(-ct->fd));
1085         exit(EXIT_FAILURE);
1086 }
1087
1088 static int signal_post_select(struct sched *s, void *context)
1089 {
1090         struct signal_task *st = context;
1091         int ret, signum;
1092
1093         ret = task_get_notification(st->task);
1094         if (ret < 0)
1095                 return ret;
1096         signum = para_next_signal(&s->rfds);
1097         switch (signum) {
1098         case SIGINT:
1099         case SIGTERM:
1100         case SIGHUP:
1101                 PARA_NOTICE_LOG("received signal %d\n", signum);
1102                 task_notify_all(s, E_AUDIOD_SIGNAL);
1103                 return -E_AUDIOD_SIGNAL;
1104         }
1105         return 0;
1106 }
1107
1108 static void command_pre_select(struct sched *s, void *context)
1109 {
1110         struct command_task *ct = context;
1111         para_fd_set(ct->fd, &s->rfds, &s->max_fileno);
1112 }
1113
1114 static int command_post_select(struct sched *s, void *context)
1115 {
1116         int ret;
1117         struct command_task *ct = context;
1118         static struct timeval last_status_dump;
1119         struct timeval tmp, delay;
1120         bool force = false;
1121
1122         ret = task_get_notification(ct->task);
1123         if (ret < 0)
1124                 return ret;
1125         ret = handle_connect(ct->fd, &s->rfds);
1126         if (ret < 0) {
1127                 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
1128                 if (ret == -E_AUDIOD_TERM) {
1129                         task_notify_all(s, -ret);
1130                         return ret;
1131                 }
1132         } else if (ret > 0)
1133                 force = true;
1134         if (force == true)
1135                 goto dump;
1136
1137         /* if last status dump was less than 500ms ago, do nothing */
1138         delay.tv_sec = 0;
1139         delay.tv_usec = 500 * 1000;
1140         tv_add(&last_status_dump, &delay, &tmp);
1141         if (tv_diff(now, &tmp, NULL) < 0)
1142                 return 0;
1143
1144         /*
1145          * If last status dump was more than 5s ago, force update. Otherwise,
1146          * update only those items that have changed.
1147          */
1148         delay.tv_sec = 5;
1149         delay.tv_usec = 0;
1150         tv_add(&last_status_dump, &delay, &tmp);
1151         if (tv_diff(now, &tmp, NULL) > 0)
1152                 force = true;
1153 dump:
1154         audiod_status_dump(force);
1155         last_status_dump = *now;
1156         return 1;
1157 }
1158
1159 static void init_command_task(struct command_task *ct)
1160 {
1161         init_local_socket(ct); /* doesn't return on errors */
1162
1163         ct->task = task_register(&(struct task_info) {
1164                 .name = "command",
1165                 .pre_select = command_pre_select,
1166                 .post_select = command_post_select,
1167                 .context = ct,
1168         }, &sched);
1169 }
1170
1171 static void close_stat_pipe(void)
1172 {
1173         if (!stat_task->ct)
1174                 return;
1175         task_reap(&stat_task->ct->task);
1176         client_close(stat_task->ct);
1177         stat_task->ct = NULL;
1178         clear_and_dump_items();
1179         stat_task->length_seconds = 0;
1180         stat_task->offset_seconds = 0;
1181         stat_task->vss_status = 0;
1182         stat_task->current_audio_format_num = -1;
1183         audiod_status_dump(true);
1184 }
1185
1186 /* avoid busy loop if server is down */
1187 static void set_stat_task_restart_barrier(unsigned seconds)
1188 {
1189         struct timeval delay = {seconds, 0};
1190         tv_add(now, &delay, &stat_task->restart_barrier);
1191 }
1192
1193 static bool must_close_slot(int slot_num)
1194 {
1195         struct slot_info *s = &slot[slot_num];
1196         struct audio_format_info *a = afi + s->format;
1197         int i;
1198
1199         if (s->format < 0)
1200                 return false;
1201         if (s->receiver_node && task_status(s->receiver_node->task) >= 0)
1202                 return false;
1203         for (i = 0; i < a->num_filters; i++)
1204                 if (s->fns && task_status(s->fns[i].task) >= 0)
1205                         return false;
1206         if (a->num_writers > 0) {
1207                 for (i = 0; i < a->num_writers; i++)
1208                         if (s->wns && task_status(s->wns[i].task) >= 0)
1209                                 return false;
1210         } else {
1211                 if (s->wns && task_status(s->wns[0].task) >= 0)
1212                         return false;
1213         }
1214         return true;
1215 }
1216
1217 static void close_slot(int slot_num)
1218 {
1219         struct slot_info *s = slot + slot_num;
1220
1221         PARA_INFO_LOG("closing slot %d\n", slot_num);
1222         close_writers(s);
1223         close_filters(s);
1224         close_receiver(slot_num);
1225         clear_slot(slot_num);
1226 }
1227
1228 static void close_unused_slots(void)
1229 {
1230         int i;
1231         bool dump = false;
1232
1233         FOR_EACH_SLOT(i)
1234                 if (must_close_slot(i)) {
1235                         close_slot(i);
1236                         dump = true;
1237                 }
1238         if (dump)
1239                 audiod_status_dump(true);
1240 }
1241
1242 /*
1243  * Cleanup all resources.
1244  *
1245  * This performs various cleanups, removes the audiod socket and closes the
1246  * connection to para_server.
1247  */
1248 static void audiod_cleanup(void)
1249 {
1250         if (socket_name)
1251                 unlink(socket_name);
1252         close_stat_pipe();
1253         close_unused_slots();
1254         close_stat_clients();
1255         free(uid_whitelist);
1256 }
1257
1258 /*
1259  * Check if any receivers/filters/writers need to be started and do so if
1260  * necessary.
1261  */
1262 static void start_stop_decoders(void)
1263 {
1264         int ret;
1265         struct slot_info *sl;
1266
1267         close_unused_slots();
1268         if (audiod_status != AUDIOD_ON ||
1269                         !(stat_task->vss_status & VSS_STATUS_FLAG_PLAYING))
1270                 return notify_receivers(E_NOT_PLAYING);
1271         if (!must_start_decoder())
1272                 return;
1273         ret = open_receiver(stat_task->current_audio_format_num);
1274         if (ret < 0) {
1275                 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
1276                 return;
1277         }
1278         sl = slot + ret;
1279         open_filters(sl);
1280         open_writers(sl);
1281         activate_grab_clients(&sched);
1282         btr_log_tree(sl->receiver_node->btrn, LL_NOTICE);
1283         audiod_status_dump(true);
1284 }
1285
1286 static void status_pre_select(struct sched *s, void *context)
1287 {
1288         struct status_task *st = context;
1289         int i, ret, cafn = stat_task->current_audio_format_num;
1290
1291         if (must_start_decoder())
1292                 goto min_delay;
1293         FOR_EACH_SLOT(i)
1294                 if (must_close_slot(i))
1295                         goto min_delay;
1296         ret = btr_node_status(st->btrn, st->min_iqs, BTR_NT_LEAF);
1297         if (ret > 0)
1298                 goto min_delay;
1299         if (st->ct && audiod_status == AUDIOD_OFF)
1300                 goto min_delay;
1301         if (!st->ct && audiod_status != AUDIOD_OFF)
1302                 sched_request_barrier_or_min_delay(&st->restart_barrier, s);
1303         if (cafn >= 0)
1304                 sched_request_barrier(&afi[cafn].restart_barrier, s);
1305         /*
1306          * If para_server is playing we'd like to have a smooth time display
1307          * even if we are running in standby mode. So we request a timeout that
1308          * expires at the next full second.
1309          */
1310         if (stat_task->vss_status & VSS_STATUS_FLAG_PLAYING)
1311                 sched_request_timeout_ms(1000 - now->tv_usec / 1000, s);
1312         return;
1313 min_delay:
1314         sched_min_delay(s);
1315 }
1316
1317 /* restart the client task if necessary */
1318 static int status_post_select(struct sched *s, void *context)
1319 {
1320         struct status_task *st = context;
1321         int ret;
1322
1323         ret = task_get_notification(st->task);
1324         if (ret < 0)
1325                 return ret;
1326         if (audiod_status == AUDIOD_OFF) {
1327                 if (!st->ct)
1328                         goto out;
1329                 if (task_status(st->ct->task) >= 0) {
1330                         task_notify(st->ct->task, E_AUDIOD_OFF);
1331                         goto out;
1332                 }
1333                 close_stat_pipe();
1334                 st->clock_diff_count = OPT_UINT32_VAL(CLOCK_DIFF_COUNT);
1335                 goto out;
1336         }
1337         if (st->ct) {
1338                 char *buf;
1339                 size_t sz;
1340
1341                 ret = btr_node_status(st->btrn, st->min_iqs, BTR_NT_LEAF);
1342                 if (ret < 0) {
1343                         close_stat_pipe();
1344                         goto out;
1345                 }
1346                 if (st->ct->status != CL_EXECUTING)
1347                         goto out;
1348                 if (ret == 0) {
1349                         struct timeval diff;
1350                         tv_diff(now, &st->last_status_read, &diff);
1351                         if (diff.tv_sec > 61)
1352                                 task_notify(st->ct->task, E_STATUS_TIMEOUT);
1353                         goto out;
1354                 }
1355                 btr_merge(st->btrn, st->min_iqs);
1356                 sz = btr_next_buffer(st->btrn, &buf);
1357                 ret = for_each_stat_item(buf, sz, update_item);
1358                 if (ret < 0) {
1359                         task_notify(st->ct->task, -ret);
1360                         goto out;
1361                 }
1362                 if (sz != ret) {
1363                         btr_consume(st->btrn, sz - ret);
1364                         st->last_status_read = *now;
1365                         st->min_iqs = 0;
1366                 } else /* current status item crosses buffers */
1367                         st->min_iqs = sz + 1;
1368                 goto out;
1369         }
1370         btr_drain(st->btrn);
1371         st->current_audio_format_num = -1;
1372         if (tv_diff(now, &st->restart_barrier, NULL) < 0)
1373                 goto out;
1374         if (st->clock_diff_count) { /* get status only one time */
1375                 char *argv[] = {"audiod", "--", "stat", "-p", "-n=1", NULL};
1376                 int argc = 5;
1377                 PARA_INFO_LOG("clock diff count: %u\n", st->clock_diff_count);
1378                 st->clock_diff_count--;
1379                 client_open(argc, argv, &st->ct, NULL, NULL, st->btrn, s);
1380                 set_stat_task_restart_barrier(2);
1381
1382         } else {
1383                 char *argv[] = {"audiod", "--", "stat", "-p", NULL};
1384                 int argc = 4;
1385                 client_open(argc, argv, &st->ct, NULL, NULL, st->btrn, s);
1386                 set_stat_task_restart_barrier(5);
1387         }
1388         free(stat_item_values[SI_basename]);
1389         stat_item_values[SI_basename] = para_strdup(
1390                 "no connection to para_server");
1391         stat_client_write_item(SI_basename);
1392         st->last_status_read = *now;
1393 out:
1394         start_stop_decoders();
1395         return 0;
1396 }
1397
1398 static void init_status_task(struct status_task *st)
1399 {
1400         memset(st, 0, sizeof(struct status_task));
1401         st->sa_time_diff_sign = 1;
1402         st->clock_diff_count = OPT_UINT32_VAL(CLOCK_DIFF_COUNT);
1403         st->current_audio_format_num = -1;
1404         st->btrn = btr_new_node(&(struct btr_node_description)
1405                 EMBRACE(.name = "stat"));
1406
1407         stat_task->task = task_register(&(struct task_info) {
1408                 .name = "stat",
1409                 .pre_select = status_pre_select,
1410                 .post_select = status_post_select,
1411                 .context = stat_task,
1412         }, &sched);
1413 }
1414
1415 static void set_initial_status(void)
1416 {
1417         audiod_status = AUDIOD_ON;
1418         if (!OPT_GIVEN(MODE))
1419                 return;
1420         if (!strcmp(OPT_STRING_VAL(MODE), "sb")) {
1421                 audiod_status = AUDIOD_STANDBY;
1422                 return;
1423         }
1424         if (!strcmp(OPT_STRING_VAL(MODE), "off")) {
1425                 audiod_status = AUDIOD_OFF;
1426                 return;
1427         }
1428         if (strcmp(OPT_STRING_VAL(MODE), "on"))
1429                 PARA_WARNING_LOG("invalid mode\n");
1430 }
1431
1432 /**
1433  * Lookup the given UID in the whitelist.
1434  *
1435  * The whitelist is the array of arguments to the --user-allow opion. If the
1436  * option was not given, the array is empty, in which case the check succeeds.
1437  *
1438  * \param uid User ID to look up.
1439  *
1440  * \return True if --user-allow was not given, or if uid matches an element of
1441  * the whitelist.
1442  */
1443 bool uid_is_whitelisted(uid_t uid)
1444 {
1445         int i;
1446
1447         if (!OPT_GIVEN(USER_ALLOW))
1448                 return true;
1449         for (i = 0; i < OPT_GIVEN(USER_ALLOW); i++)
1450                 if (uid == uid_whitelist[i])
1451                         return true;
1452         return false;
1453 }
1454
1455 static void handle_help_flags(void)
1456 {
1457         char *help;
1458         bool d = OPT_GIVEN(DETAILED_HELP);
1459
1460         if (d)
1461                 help = lls_long_help(CMD_PTR);
1462         else if (OPT_GIVEN(HELP))
1463                 help = lls_short_help(CMD_PTR);
1464         else
1465                 return;
1466         printf("%s\n", help);
1467         free(help);
1468         print_receiver_helps(d);
1469         print_filter_helps(d);
1470         print_writer_helps(d);
1471         exit(EXIT_SUCCESS);
1472 }
1473
1474 /**
1475  * the main function of para_audiod
1476  *
1477  * \param argc usual argument count
1478  * \param argv usual argument vector
1479  *
1480  * \return EXIT_SUCCESS or EXIT_FAILURE
1481  *
1482  * \sa para_audiod(1)
1483  * */
1484 int main(int argc, char *argv[])
1485 {
1486         int ret, i;
1487         struct command_task command_task_struct, *cmd_task = &command_task_struct;
1488         char *errctx;
1489
1490         valid_fd_012();
1491         ret = lls(lls_parse(argc, argv, CMD_PTR, &lpr, &errctx));
1492         if (ret < 0)
1493                 goto out;
1494         daemon_set_loglevel(ENUM_STRING_VAL(LOGLEVEL));
1495         daemon_drop_privileges_or_die(OPT_STRING_VAL(USER),
1496                 OPT_STRING_VAL(GROUP));
1497         version_handle_flag("audiod", OPT_GIVEN(VERSION));
1498         handle_help_flags();
1499         parse_config_or_die();
1500         init_random_seed_or_die();
1501         daemon_set_priority(OPT_UINT32_VAL(PRIORITY));
1502         recv_init();
1503         if (daemon_init_colors_or_die(OPT_UINT32_VAL(COLOR), COLOR_AUTO,
1504                         COLOR_NO, OPT_GIVEN(LOGFILE))) {
1505                 for (i = 0; i < OPT_GIVEN(LOG_COLOR); i++)
1506                         daemon_set_log_color_or_die(lls_string_val(i,
1507                                 OPT_RESULT(LOG_COLOR)));
1508         }
1509         daemon_set_flag(DF_LOG_TIME);
1510         daemon_set_flag(DF_LOG_HOSTNAME);
1511         daemon_set_flag(DF_LOG_LL);
1512         if (OPT_GIVEN(LOG_TIMING))
1513                 daemon_set_flag(DF_LOG_TIMING);
1514         if (OPT_GIVEN(LOGFILE)) {
1515                 daemon_set_logfile(OPT_STRING_VAL(LOGFILE));
1516                 daemon_open_log_or_die();
1517         }
1518         ret = parse_stream_args();
1519         if (ret < 0) {
1520                 PARA_EMERG_LOG("%s\n", para_strerror(-ret));
1521                 exit(EXIT_FAILURE);
1522         }
1523         daemon_log_welcome("audiod");
1524         daemon_set_start_time();
1525         set_initial_status();
1526         FOR_EACH_SLOT(i)
1527                 clear_slot(i);
1528         setup_signal_handling();
1529
1530         init_status_task(stat_task);
1531         init_command_task(cmd_task);
1532
1533         if (OPT_GIVEN(DAEMON))
1534                 daemonize(false /* parent exits immediately */);
1535
1536         signal_task->task = task_register(&(struct task_info) {
1537                 .name = "signal",
1538                 .pre_select = signal_pre_select,
1539                 .post_select = signal_post_select,
1540                 .context = signal_task,
1541         }, &sched);
1542
1543         sched.default_timeout.tv_sec = 2;
1544         sched.default_timeout.tv_usec = 999 * 1000;
1545         ret = schedule(&sched);
1546         audiod_cleanup();
1547         sched_shutdown(&sched);
1548         signal_shutdown(signal_task);
1549
1550 out:
1551         lls_free_parse_result(lpr, CMD_PTR);
1552         if (errctx)
1553                 PARA_ERROR_LOG("%s\n", errctx);
1554         if (ret < 0)
1555                 PARA_EMERG_LOG("%s\n", para_strerror(-ret));
1556         return ret < 0? EXIT_FAILURE : EXIT_SUCCESS;
1557 }