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
  19 #include "para.h"
  20 #include "error.h"
  21 #include "crypt.h"
  22 #include "audiod.cmdline.h"
  23 #include "list.h"
  24 #include "sched.h"
  25 #include "ggo.h"
  26 #include "buffer_tree.h"
  27 #include "recv.h"
  28 #include "filter.h"
  29 #include "grab_client.h"
  30 #include "client.cmdline.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 "write_common.h"
  39 #include "signal.h"
  40 #include "version.h"
  41
  42 /** Array of error strings. */
  43 DEFINE_PARA_ERRLIST;
  44
  45 __printf_2_3 void (*para_log)(int, const char*, ...) = daemon_log;
  46 /** define the array containing all supported audio formats */
  47 const char *audio_formats[] = {AUDIOD_AUDIO_FORMAT_ARRAY NULL};
  48
  49 DEFINE_RECEIVER_ARRAY;
  50
  51 /** Defines how audiod handles one supported audio format. */
  52 struct audio_format_info {
  53         /** pointer to the receiver for this audio format */
  54         struct receiver *receiver;
  55         /** the receiver configuration */
  56         void *receiver_conf;
  57         /** the number of filters that should be activated for this audio format */
  58         unsigned int num_filters;
  59         /** Array of filter numbers to be activated. */
  60         unsigned *filter_nums;
  61         /** Pointer to the array of filter configurations. */
  62         void **filter_conf;
  63         /** the number of filters that should be activated for this audio format */
  64         unsigned int num_writers;
  65         /** Array of writer numbers to be activated. */
  66         int *writer_nums;
  67         /** pointer to the array of writer configurations */
  68         void **writer_conf;
  69         /** do not start receiver/filters/writer before this time */
  70         struct timeval restart_barrier;
  71 };
  72
  73 /* Describes one instance of a receiver-filter-writer chain. */
  74 struct slot_info {
  75         /* Number of the audio format in this slot. */
  76         int format;
  77         /* The stream_start status item announced by para_server.  */
  78         struct timeval server_stream_start;
  79         /* The offset status item announced by para_server. */
  80         unsigned offset_seconds;
  81         /* The seconds_total status item announced by para_server. */
  82         unsigned seconds_total;
  83         /* The receiver info associated with this slot. */
  84         struct receiver_node *receiver_node;
  85         /* The array of filter nodes. */
  86         struct filter_node *fns;
  87         /* The array of writers attached to the last filter. */
  88         struct writer_node *wns;
  89 };
  90
  91 /** Maximal number of simultaneous instances. */
  92 #define MAX_STREAM_SLOTS 5
  93
  94 /** Iterate over all slots. */
  95 #define FOR_EACH_SLOT(_slot) for (_slot = 0; _slot < MAX_STREAM_SLOTS; _slot++)
  96
  97 /**
  98  * para_audiod uses \p MAX_STREAM_SLOTS different slots, each of which may
  99  * be associated with a receiver/filter/writer triple. This array holds all
 100  * information on the status of these slots.
 101  *
 102  * \sa struct slot_info
 103  * */
 104 struct slot_info slot[MAX_STREAM_SLOTS];
 105
 106 /** The vss status flags audiod is interested in. */
 107 enum vss_status_flags {
 108         /** Whether the 'N' flag is set. */
 109         VSS_STATUS_FLAG_NEXT = 1,
 110         /** The 'P' flag is set. */
 111         VSS_STATUS_FLAG_PLAYING = 2,
 112 };
 113
 114 /**
 115  * The scheduler instance of para_audiod.
 116  *
 117  * This is needed also in audiod_command.c (for the tasks command), so it can
 118  * not be made static.
 119  */
 120 struct sched sched = {.max_fileno = 0};
 121
 122 /* The task for obtaining para_server's status (para_client stat). */
 123 struct status_task {
 124         /** The associated task structure of audiod. */
 125         struct task *task;
 126         /** Client data associated with the stat task. */
 127         struct client_task *ct;
 128         /** Do not restart client command until this time. */
 129         struct timeval restart_barrier;
 130         /** Last time we received status data from para_server. */
 131         struct timeval last_status_read;
 132         size_t min_iqs;
 133         /** The offset value announced by para_server. */
 134         int offset_seconds;
 135         /** The length of the current audio file as announced by para_server. */
 136         int length_seconds;
 137         /** The start of the current stream from the view of para_server. */
 138         struct timeval server_stream_start;
 139         /** The average time deviation between para_server and para_audiod. */
 140         struct timeval sa_time_diff;
 141         /** Whether client time is ahead of server time. */
 142         int sa_time_diff_sign;
 143         /** The 'P' and the 'N' flags as announced by para_server. */
 144         enum vss_status_flags vss_status;
 145         /** Number of times the clock difference is to be checked. */
 146         unsigned clock_diff_count;
 147         /** When to start the next check for clock difference. */
 148         struct timeval clock_diff_barrier;
 149         /** Number of the audio format as announced by para_server. */
 150         int current_audio_format_num;
 151         /* The status task btrn is the child of the client task. */
 152         struct btr_node *btrn;
 153 };
 154
 155 /** The array of status items sent by para_server. */
 156 char *stat_item_values[NUM_STAT_ITEMS] = {NULL};
 157
 158 /**
 159  * the current mode of operation of which can be changed by the on/off/cycle
 160  * commands. It is either, AUDIOD_OFF, AUDIOD_ON or AUDIOD_STANDBY.
 161  */
 162 int audiod_status = AUDIOD_ON;
 163
 164 /**
 165  * the gengetopt args_info struct that holds information on all command line
 166  * arguments
 167  */
 168 static struct audiod_args_info conf;
 169
 170 static char *socket_name;
 171 static struct audio_format_info afi[NUM_AUDIO_FORMATS];
 172
 173 static struct signal_task *signal_task;
 174
 175 static struct status_task status_task_struct;
 176
 177 static uid_t *uid_whitelist;
 178
 179 /**
 180  * the task that calls the status command of para_server
 181  *
 182  * \sa struct status_task
 183  */
 184 static struct status_task *stat_task = &status_task_struct;
 185
 186 /*
 187  * The task for handling audiod commands.
 188  *
 189  * We need two listening sockets for backward compability: on Linux systems
 190  * fd[0] is an abstract socket (more precisely, a socket bound to an address in
 191  * the abstract namespace), and fd[1] is the usual pathname socket. On other
 192  * systems, fd[0] is negative, and only the pathname socket is used.
 193  *
 194  * For 0.5.x we accept connections on both sockets to make sure that old
 195  * para_audioc versions can still connect. New versions use only the abstract
 196  * socket. Hence after v0.6.0 we can go back to a single socket, either an
 197  * abstract one (Linux) or a pathname socket (all other systems).
 198  */
 199 struct command_task {
 200         /** The local listening sockets. */
 201         int fd[2];
 202         /** the associated task structure */
 203         struct task *task;
 204 };
 205
 206 /** iterate over all supported audio formats */
 207 #define FOR_EACH_AUDIO_FORMAT(af) for (af = 0; af < NUM_AUDIO_FORMATS; af++)
 208
 209 /**
 210  * Get the audio format number.
 211  *
 212  * \param name The name of the audio format.
 213  *
 214  * \return The audio format number on success, -E_UNSUPPORTED_AUDIO_FORMAT if
 215  * \a name is not a supported audio format.
 216  */
 217 static int get_audio_format_num(const char *name)
 218 {
 219         int i;
 220
 221         while (para_isspace(*name))
 222                 name++;
 223         FOR_EACH_AUDIO_FORMAT(i)
 224                 if (!strcmp(name, audio_formats[i]))
 225                         return i;
 226         return -E_UNSUPPORTED_AUDIO_FORMAT;
 227 }
 228
 229 /**
 230  * Return the flags for the \a decoder_flags status item.
 231  *
 232  * Allocates a string which contains one octal digit per slot.  Bit zero (value
 233  * 1) is set if a receiver is active. Bit one (value 2) and bit three (value 4)
 234  * have the analogous meaning for filter and writer, respectively.
 235  *
 236  * \return String that must be freed by the caller.
 237  */
 238 __malloc char *audiod_get_decoder_flags(void)
 239 {
 240         int i;
 241         char flags[MAX_STREAM_SLOTS + 1];
 242
 243         FOR_EACH_SLOT(i) {
 244                 struct slot_info *s = &slot[i];
 245                 char flag = '0';
 246                 if (s->receiver_node)
 247                         flag += 1;
 248                 if (s->fns)
 249                         flag += 2;
 250                 if (s->wns)
 251                         flag += 4;
 252                 flags[i] = flag;
 253         }
 254         flags[MAX_STREAM_SLOTS] = '\0';
 255         return para_strdup(flags);
 256 }
 257
 258 static int get_matching_audio_format_nums(const char *re)
 259 {
 260         int i, ret;
 261         regex_t preg;
 262
 263         ret = para_regcomp(&preg, re, REG_EXTENDED | REG_NOSUB);
 264         if (ret < 0)
 265                 return ret;
 266         ret = 0;
 267         FOR_EACH_AUDIO_FORMAT(i)
 268                 if (regexec(&preg, audio_formats[i], 0, NULL, 0) != REG_NOMATCH)
 269                         ret |= (1 << i);
 270         regfree(&preg);
 271         return ret;
 272 }
 273
 274 static int get_play_time_slot_num(void)
 275 {
 276         int i, oldest_slot = -1;
 277         struct timeval oldest_wstime = {0, 0};
 278
 279         FOR_EACH_SLOT(i) {
 280                 struct slot_info *s = &slot[i];
 281                 struct timeval wstime;
 282                 if (!s->wns || !s->wns[0].btrn)
 283                         continue;
 284                 btr_get_node_start(s->wns[0].btrn, &wstime);
 285                 if (oldest_slot >= 0 && tv_diff(&wstime, &oldest_wstime, NULL) > 0)
 286                         continue;
 287                 oldest_wstime = wstime;
 288                 oldest_slot = i;
 289         }
 290         return oldest_slot;
 291 }
 292
 293 /**
 294  * Compute the play time based on information of the current slot.
 295  *
 296  * This computes a string of the form "0:07 [3:33] (3%/3:40)" using information
 297  * from the status items received from para_server and the start time of the
 298  * (first) writer of the current slot.
 299  *
 300  * It has to take into account that the stream was probably not started at
 301  * the beginning of the file, that the clock between the server and the client
 302  * host may differ and that playback of the stream was delayed, e.g. because
 303  * the prebuffer filter is used in the filter configuration.
 304  *
 305  * If no writer is active, for example because para_audiod runs in standby
 306  * mode, an approximation based only on the status items is computed and the
 307  * returned string is prefixed with "~".
 308  *
 309  * \return A string that must be freed by the caller.
 310  */
 311 char *get_time_string(void)
 312 {
 313         int ret, seconds = 0, length = stat_task->length_seconds;
 314         struct timeval *tmp, sum, sss, /* server stream start */
 315                 rstime, /* receiver start time */
 316                 wstime, /* writer start time */
 317                 wtime, /* now - writer start */
 318                 rskip; /* receiver start - sss */
 319         int slot_num = get_play_time_slot_num();
 320         struct slot_info *s = slot_num < 0? NULL : &slot[slot_num];
 321         char *msg;
 322
 323         if (audiod_status == AUDIOD_OFF)
 324                 goto empty;
 325         if (stat_task->server_stream_start.tv_sec == 0) {
 326                 if (stat_task->vss_status & VSS_STATUS_FLAG_PLAYING)
 327                         goto out; /* server is about to change file */
 328                 if (length > 0) /* paused */
 329                         return NULL;
 330                 goto empty; /* stopped */
 331         }
 332         /*
 333          * Valid status items and playing, set length and tmp to the stream
 334          * start. We use the slot info and fall back to the info from current
 335          * status items if no slot info is available.
 336          */
 337         tmp = &stat_task->server_stream_start;
 338         if (s && s->wns && s->wns[0].btrn) { /* writer active in this slot */
 339                 btr_get_node_start(s->wns[0].btrn, &wstime);
 340                 if (wstime.tv_sec != 0) { /* writer wrote something */
 341                         if (s->server_stream_start.tv_sec == 0) {
 342                                 /* copy status info to slot */
 343                                 s->server_stream_start = stat_task->server_stream_start;
 344                                 s->offset_seconds = stat_task->offset_seconds;
 345                                 s->seconds_total = stat_task->length_seconds;
 346                         }
 347                         length = s->seconds_total;
 348                         tmp = &s->server_stream_start;
 349                 }
 350         }
 351         if (stat_task->sa_time_diff_sign > 0)
 352                 tv_diff(tmp, &stat_task->sa_time_diff, &sss);
 353         else
 354                 tv_add(tmp, &stat_task->sa_time_diff, &sss);
 355         if (!s || !s->wns || !s->wns[0].btrn || wstime.tv_sec == 0) {
 356                 struct timeval diff;
 357                 tv_diff(now, &sss, &diff);
 358                 seconds = diff.tv_sec + stat_task->offset_seconds;
 359                 goto out;
 360         }
 361         tv_diff(now, &wstime, &wtime);
 362         //PARA_CRIT_LOG("offset %d\n", s->offset_seconds);
 363         seconds = s->offset_seconds;
 364         if (s->receiver_node->btrn) {
 365                 btr_get_node_start(s->receiver_node->btrn, &rstime);
 366                 ret = tv_diff(&rstime, &sss, &rskip);
 367                 if (ret > 0 && rskip.tv_sec > 2) {
 368                         /* audiod was started in the middle of the stream */
 369                         tv_add(&wtime, &rskip, &sum);
 370                         seconds += sum.tv_sec;
 371                 } else
 372                         seconds += wtime.tv_sec;
 373         } else
 374                 seconds += wtime.tv_sec;
 375 out:
 376         seconds = PARA_MIN(seconds, length);
 377         seconds = PARA_MAX(seconds, 0);
 378         msg = make_message(
 379                 "%s%d:%02d [%d:%02d] (%d%%/%d:%02d)",
 380                 s? "" : "~",
 381                 seconds / 60,
 382                 seconds % 60,
 383                 (length - seconds) / 60,
 384                 (length - seconds) % 60,
 385                 length? (seconds * 100 + length / 2) / length : 0,
 386                 length / 60,
 387                 length % 60
 388         );
 389         //PARA_DEBUG_LOG("slot %d: %s\n", slot_num, msg);
 390         return msg;
 391 empty:
 392         return para_strdup(NULL);
 393 }
 394
 395 static void parse_config_or_die(void)
 396 {
 397         int ret, i;
 398         char *config_file;
 399         struct audiod_cmdline_parser_params params = {
 400                 .override = 0,
 401                 .initialize = 0,
 402                 .check_required = 1,
 403                 .check_ambiguity = 0,
 404                 .print_errors = 1
 405         };
 406
 407         if (conf.config_file_given)
 408                 config_file = para_strdup(conf.config_file_arg);
 409         else {
 410                 char *home = para_homedir();
 411                 config_file = make_message("%s/.paraslash/audiod.conf", home);
 412                 free(home);
 413         }
 414         ret = file_exists(config_file);
 415         if (conf.config_file_given && !ret) {
 416                 PARA_EMERG_LOG("can not read config file %s\n", config_file);
 417                 free(config_file);
 418                 goto err;
 419         }
 420         if (ret) {
 421                 audiod_cmdline_parser_config_file(config_file, &conf, &params);
 422                 daemon_set_loglevel(conf.loglevel_arg);
 423         }
 424         free(config_file);
 425         if (conf.user_allow_given > 0) {
 426                 uid_whitelist = para_malloc(conf.user_allow_given
 427                         * sizeof(uid_t));
 428                 for (i = 0; i < conf.user_allow_given; i++) {
 429                         int32_t val;
 430                         struct passwd *pw;
 431                         ret = para_atoi32(conf.user_allow_arg[i], &val);
 432                         if (ret >= 0) {
 433                                 uid_whitelist[i] = val;
 434                                 continue;
 435                         }
 436                         errno = 0; /* see getpwnam(3) */
 437                         pw = getpwnam(conf.user_allow_arg[i]);
 438                         if (!pw) {
 439                                 PARA_EMERG_LOG("invalid username: %s\n",
 440                                         conf.user_allow_arg[i]);
 441                                 goto err;
 442                         }
 443                         uid_whitelist[i] = pw->pw_uid;
 444                 }
 445         }
 446         return;
 447 err:
 448         exit(EXIT_FAILURE);
 449 }
 450
 451 static void setup_signal_handling(void)
 452 {
 453         signal_task = signal_init_or_die();
 454         para_install_sighandler(SIGINT);
 455         para_install_sighandler(SIGTERM);
 456         para_install_sighandler(SIGHUP);
 457         para_sigaction(SIGPIPE, SIG_IGN);
 458 }
 459
 460 static void clear_slot(int slot_num)
 461 {
 462         struct slot_info *s = &slot[slot_num];
 463
 464         PARA_INFO_LOG("clearing slot %d\n", slot_num);
 465         memset(s, 0, sizeof(struct slot_info));
 466         s->format = -1;
 467 }
 468
 469 static void close_receiver(int slot_num)
 470 {
 471         struct slot_info *s = &slot[slot_num];
 472         struct audio_format_info *a;
 473
 474         if (s->format < 0 || !s->receiver_node)
 475                 return;
 476         a = &afi[s->format];
 477         PARA_NOTICE_LOG("closing %s receiver in slot %d\n",
 478                 audio_formats[s->format], slot_num);
 479         a->receiver->close(s->receiver_node);
 480         btr_remove_node(&s->receiver_node->btrn);
 481         task_reap(&s->receiver_node->task);
 482         free(s->receiver_node);
 483         s->receiver_node = NULL;
 484         stat_task->current_audio_format_num = -1;
 485         tv_add(now, &(struct timeval)EMBRACE(0, 200 * 1000),
 486                 &a->restart_barrier);
 487 }
 488
 489 static void writer_cleanup(struct writer_node *wn)
 490 {
 491         struct writer *w;
 492
 493         if (!wn)
 494                 return;
 495         w = writers + wn->writer_num;
 496         PARA_INFO_LOG("closing %s\n", writer_names[wn->writer_num]);
 497         w->close(wn);
 498         btr_remove_node(&wn->btrn);
 499         task_reap(&wn->task);
 500 }
 501
 502 static void close_writers(struct slot_info *s)
 503 {
 504         struct audio_format_info *a;
 505         int i;
 506
 507         if (s->format < 0)
 508                 return;
 509         assert(s->wns);
 510         a = afi + s->format;
 511         if (a->num_writers == 0)
 512                 writer_cleanup(s->wns);
 513         else {
 514                 for (i = 0; i < a->num_writers; i++)
 515                         writer_cleanup(s->wns + i);
 516         }
 517         free(s->wns);
 518         s->wns = NULL;
 519 }
 520
 521 static void close_filters(struct slot_info *s)
 522 {
 523         int i;
 524         struct audio_format_info *a = afi + s->format;
 525         if (a->num_filters == 0)
 526                 return;
 527         for (i = a->num_filters - 1; i >= 0; i--) {
 528                 struct filter_node *fn = s->fns + i;
 529                 const struct filter *f;
 530
 531                 if (!fn)
 532                         continue;
 533                 f = filter_get(fn->filter_num);
 534                 if (f->close)
 535                         f->close(fn);
 536                 btr_remove_node(&fn->btrn);
 537                 task_reap(&fn->task);
 538         }
 539         free(s->fns);
 540         s->fns = NULL;
 541 }
 542
 543 static void notify_receivers(int error)
 544 {
 545         int i;
 546
 547         FOR_EACH_SLOT(i) {
 548                 struct slot_info *s = slot + i;
 549                 if (s->format < 0)
 550                         continue;
 551                 if (!s->receiver_node)
 552                         continue;
 553                 task_notify(s->receiver_node->task, error);
 554         }
 555 }
 556
 557 static int get_empty_slot(void)
 558 {
 559         int i;
 560         struct slot_info *s;
 561
 562         FOR_EACH_SLOT(i) {
 563                 s = &slot[i];
 564                 if (s->format < 0) {
 565                         clear_slot(i);
 566                         return i;
 567                 }
 568                 if (s->wns || s->receiver_node || s->fns)
 569                         continue;
 570                 clear_slot(i);
 571                 return i;
 572         }
 573         return -E_NO_MORE_SLOTS;
 574 }
 575
 576 static void open_filters(struct slot_info *s)
 577 {
 578         struct audio_format_info *a = afi + s->format;
 579         struct filter_node *fn;
 580         int nf = a->num_filters;
 581         struct btr_node *parent;
 582         int i;
 583
 584         if (nf == 0)
 585                 return;
 586         PARA_INFO_LOG("opening %s filters\n", audio_formats[s->format]);
 587         assert(s->fns == NULL);
 588         s->fns = para_calloc(nf * sizeof(struct filter_node));
 589         parent = s->receiver_node->btrn;
 590         for (i = 0; i < nf; i++) {
 591                 char buf[20];
 592                 const struct filter *f = filter_get(a->filter_nums[i]);
 593                 fn = s->fns + i;
 594                 fn->filter_num = a->filter_nums[i];
 595                 fn->conf = a->filter_conf[i];
 596                 fn->btrn = btr_new_node(&(struct btr_node_description)
 597                         EMBRACE(.name = f->name, .parent = parent,
 598                                 .handler = f->execute, .context = fn));
 599
 600                 if (f->open)
 601                         f->open(fn);
 602                 sprintf(buf, "%s (slot %d)", f->name, (int)(s - slot));
 603                 fn->task = task_register(&(struct task_info) {
 604                         .name = buf,
 605                         .pre_select = f->pre_select,
 606                         .post_select = f->post_select,
 607                         .context = fn,
 608                 }, &sched);
 609                 parent = fn->btrn;
 610                 PARA_NOTICE_LOG("%s filter %d/%d (%s) started in slot %d\n",
 611                         audio_formats[s->format], i,  nf, f->name, (int)(s - slot));
 612         }
 613 }
 614
 615 static void open_writers(struct slot_info *s)
 616 {
 617         int i;
 618         struct audio_format_info *a = afi + s->format;
 619         struct writer_node *wn;
 620         struct btr_node *parent = s->fns[a->num_filters - 1].btrn;
 621
 622         assert(s->wns == NULL);
 623         s->wns = para_calloc(PARA_MAX(1U, a->num_writers)
 624                 * sizeof(struct writer_node));
 625         for (i = 0; i < a->num_writers; i++) {
 626                 wn = s->wns + i;
 627                 wn->conf = a->writer_conf[i];
 628                 wn->writer_num = a->writer_nums[i];
 629                 register_writer_node(wn, parent, &sched);
 630                 PARA_NOTICE_LOG("%s writer started in slot %d\n",
 631                         writer_names[a->writer_nums[i]], (int)(s - slot));
 632         }
 633 }
 634
 635 /* returns slot num on success */
 636 static int open_receiver(int format)
 637 {
 638         struct audio_format_info *a = &afi[format];
 639         struct slot_info *s;
 640         int ret, slot_num;
 641         struct receiver *r = a->receiver;
 642         struct receiver_node *rn;
 643
 644         tv_add(now, &(struct timeval)EMBRACE(2, 0), &a->restart_barrier);
 645         ret = get_empty_slot();
 646         if (ret < 0)
 647                 return ret;
 648         slot_num = ret;
 649         rn = para_calloc(sizeof(*rn));
 650         rn->receiver = r;
 651         rn->conf = a->receiver_conf;
 652         rn->btrn = btr_new_node(&(struct btr_node_description)
 653                 EMBRACE(.name = r->name, .context = rn));
 654         ret = r->open(rn);
 655         if (ret < 0) {
 656                 btr_remove_node(&rn->btrn);
 657                 free(rn);
 658                 return ret;
 659         }
 660         s = &slot[slot_num];
 661         s->format = format;
 662         s->receiver_node = rn;
 663         PARA_NOTICE_LOG("started %s: %s receiver in slot %d\n",
 664                 audio_formats[format], r->name, slot_num);
 665         rn->task = task_register(&(struct task_info) {
 666                 .name = r->name,
 667                 .pre_select = r->pre_select,
 668                 .post_select = r->post_select,
 669                 .context = rn,
 670         }, &sched);
 671         return slot_num;
 672 }
 673
 674 static bool receiver_running(void)
 675 {
 676         int i;
 677         long unsigned ss1 = stat_task->server_stream_start.tv_sec;
 678
 679         FOR_EACH_SLOT(i) {
 680                 struct slot_info *s = &slot[i];
 681                 long unsigned ss2 = s->server_stream_start.tv_sec;
 682
 683                 if (!s->receiver_node)
 684                         continue;
 685                 if (task_status(s->receiver_node->task) >= 0)
 686                         return true;
 687                 if (ss1 == ss2)
 688                         return true;
 689         }
 690         return false;
 691 }
 692
 693 /**
 694  * Return the root node of the current buffer tree.
 695  *
 696  * This is only used for stream grabbing.
 697  *
 698  * \return \p NULL if no slot is currently active. If more than one buffer tree
 699  * exists, the node corresponding to the most recently started receiver is
 700  * returned.
 701  */
 702 struct btr_node *audiod_get_btr_root(void)
 703 {
 704         int i, newest_slot = -1;
 705         struct timeval newest_rstime = {0, 0};
 706
 707         FOR_EACH_SLOT(i) {
 708                 struct slot_info *s = &slot[i];
 709                 struct timeval rstime;
 710                 if (!s->receiver_node)
 711                         continue;
 712                 if (task_status(s->receiver_node->task) < 0)
 713                         continue;
 714                 btr_get_node_start(s->receiver_node->btrn, &rstime);
 715                 if (newest_slot >= 0 && tv_diff(&rstime, &newest_rstime, NULL) < 0)
 716                         continue;
 717                 newest_rstime = rstime;
 718                 newest_slot = i;
 719         }
 720         if (newest_slot == -1)
 721                 return NULL;
 722         return slot[newest_slot].receiver_node->btrn;
 723 }
 724
 725 /* whether a new instance of a decoder should be started. */
 726 static bool must_start_decoder(void)
 727 {
 728         int cafn = stat_task->current_audio_format_num;
 729         unsigned vs = stat_task->vss_status;
 730
 731         if (audiod_status != AUDIOD_ON)
 732                 return false;
 733         if (cafn < 0)
 734                 return false;
 735         if (!stat_task->ct)
 736                 return false;
 737         if (vs & VSS_STATUS_FLAG_NEXT)
 738                 return false;
 739         if (!(vs & VSS_STATUS_FLAG_PLAYING))
 740                 return false;
 741         if (receiver_running())
 742                 return false;
 743         if (tv_diff(now, &afi[cafn].restart_barrier, NULL) < 0)
 744                 return false;
 745         return true;
 746 }
 747
 748 static void compute_time_diff(const struct timeval *status_time)
 749 {
 750         struct timeval tmp, diff;
 751         static unsigned count;
 752         int sign, sa_time_diff_sign = stat_task->sa_time_diff_sign;
 753         const struct timeval max_deviation = {0, 500 * 1000};
 754         const int time_smooth = 5;
 755
 756         sign = tv_diff(status_time, now, &diff);
 757 //              PARA_NOTICE_LOG("%s: sign = %i, sa_time_diff_sign = %i\n", __func__,
 758 //                      sign, sa_time_diff_sign);
 759         if (!count) {
 760                 sa_time_diff_sign = sign;
 761                 stat_task->sa_time_diff = diff;
 762                 count++;
 763                 goto out;
 764         }
 765         if (count > 5) {
 766                 int s = tv_diff(&diff, &stat_task->sa_time_diff, &tmp);
 767                 if (tv_diff(&max_deviation, &tmp, NULL) < 0)
 768                         PARA_WARNING_LOG("time diff jump: %lums\n",
 769                                 s * tv2ms(&tmp));
 770         }
 771         count++;
 772         sa_time_diff_sign = tv_convex_combination(
 773                 sa_time_diff_sign * time_smooth, &stat_task->sa_time_diff,
 774                 count > 10? sign : sign * time_smooth, &diff,
 775                 &tmp);
 776         stat_task->sa_time_diff = tmp;
 777         PARA_INFO_LOG("time diff (cur/avg): %s%lums/%s%lums\n",
 778                 sign < 0? "-" : "+",
 779                 tv2ms(&diff),
 780                 sa_time_diff_sign < 0? "-" : "+",
 781                 tv2ms(&stat_task->sa_time_diff)
 782         );
 783 out:
 784         stat_task->sa_time_diff_sign = sa_time_diff_sign;
 785 }
 786
 787 static int update_item(int itemnum, char *buf)
 788 {
 789         long unsigned sec, usec;
 790
 791         if (stat_task->clock_diff_count && itemnum != SI_CURRENT_TIME)
 792                 return 1;
 793         free(stat_item_values[itemnum]);
 794         stat_item_values[itemnum] = para_strdup(buf);
 795         stat_client_write_item(itemnum);
 796         switch (itemnum) {
 797         case SI_STATUS_FLAGS:
 798                 stat_task->vss_status = 0;
 799                 if (strchr(buf, 'N'))
 800                         stat_task->vss_status |= VSS_STATUS_FLAG_NEXT;
 801                 if (strchr(buf, 'P'))
 802                         stat_task->vss_status |= VSS_STATUS_FLAG_PLAYING;
 803                 break;
 804         case SI_OFFSET:
 805                 stat_task->offset_seconds = atoi(buf);
 806                 break;
 807         case SI_SECONDS_TOTAL:
 808                 stat_task->length_seconds = atoi(buf);
 809                 break;
 810         case SI_STREAM_START:
 811                 if (sscanf(buf, "%lu.%lu", &sec, &usec) == 2) {
 812                         stat_task->server_stream_start.tv_sec = sec;
 813                         stat_task->server_stream_start.tv_usec = usec;
 814                 }
 815                 break;
 816         case SI_CURRENT_TIME:
 817                 if (sscanf(buf, "%lu.%lu", &sec, &usec) == 2) {
 818                         struct timeval tv = {sec, usec};
 819                         compute_time_diff(&tv);
 820                 }
 821                 break;
 822         case SI_FORMAT:
 823                 stat_task->current_audio_format_num
 824                         = get_audio_format_num(buf);
 825         }
 826         return 1;
 827 }
 828
 829 static int parse_stream_command(const char *txt, char **cmd)
 830 {
 831         int ret, len;
 832         char *re, *p = strchr(txt, ':');
 833
 834         if (!p)
 835                 return -E_MISSING_COLON;
 836         *cmd = p + 1;
 837         len = p - txt;
 838         re = malloc(len + 1);
 839         strncpy(re, txt, len);
 840         re[len] = '\0';
 841         ret = get_matching_audio_format_nums(re);
 842         free(re);
 843         return ret;
 844 }
 845
 846 static int add_filter(int format, char *cmdline)
 847 {
 848         struct audio_format_info *a = &afi[format];
 849         int filter_num, nf = a->num_filters;
 850         void *cfg;
 851
 852         filter_num = check_filter_arg(cmdline, &cfg);
 853         if (filter_num < 0)
 854                 return filter_num;
 855         a->filter_conf = para_realloc(a->filter_conf,
 856                 (nf + 1) * sizeof(void *));
 857         a->filter_nums = para_realloc(a->filter_nums,
 858                 (nf + 1) * sizeof(unsigned));
 859         a->filter_nums[nf] = filter_num;
 860         a->filter_conf[nf] = cfg;
 861         a->num_filters++;
 862         PARA_INFO_LOG("%s filter %d: %s\n", audio_formats[format], nf,
 863                 filter_get(filter_num)->name);
 864         return filter_num;
 865 }
 866
 867 static int parse_writer_args(void)
 868 {
 869         int i, ret;
 870         char *cmd;
 871         struct audio_format_info *a;
 872
 873         for (i = 0; i < conf.writer_given; i++) {
 874                 void *wconf;
 875                 int j, nw, writer_num, af_mask;
 876
 877                 ret = parse_stream_command(conf.writer_arg[i], &cmd);
 878                 if (ret < 0)
 879                         return ret;
 880                 af_mask = ret;
 881                 FOR_EACH_AUDIO_FORMAT(j) {
 882                         a = afi + j;
 883                         if ((af_mask & (1 << j)) == 0) /* no match */
 884                                 continue;
 885                         wconf = check_writer_arg_or_die(cmd, &writer_num);
 886                         nw = a->num_writers;
 887                         a->writer_nums = para_realloc(a->writer_nums, (nw + 1) * sizeof(int));
 888                         a->writer_conf = para_realloc(a->writer_conf, (nw + 1) * sizeof(void *));
 889                         a->writer_nums[nw] = writer_num;
 890                         a->writer_conf[nw] = wconf;
 891                         PARA_INFO_LOG("%s writer #%d: %s\n", audio_formats[j],
 892                                 nw, writer_names[writer_num]);
 893                         a->num_writers++;
 894                 }
 895         }
 896         /* Use default writer for audio formats which are not yet set up. */
 897         FOR_EACH_AUDIO_FORMAT(i) {
 898                 void *writer_conf;
 899                 int writer_num;
 900                 a = afi + i;
 901                 if (a->num_writers > 0)
 902                         continue; /* already set up */
 903                 writer_conf = check_writer_arg_or_die(NULL, &writer_num);
 904                 a->writer_nums = para_malloc(sizeof(int));
 905                 a->writer_nums[0] = writer_num;
 906                 a->writer_conf = para_malloc(sizeof(void *));
 907                 a->writer_conf[0] = writer_conf;
 908                 a->num_writers = 1;
 909                 PARA_INFO_LOG("%s writer: %s (default)\n", audio_formats[i],
 910                         writer_names[writer_num]);
 911         }
 912         return 1;
 913 }
 914
 915 static int parse_receiver_args(void)
 916 {
 917         int i, ret, receiver_num;
 918         char *cmd = NULL;
 919         struct audio_format_info *a;
 920
 921         for (i = conf.receiver_given - 1; i >= 0; i--) {
 922                 char *arg;
 923                 int j, af_mask;
 924
 925                 ret = parse_stream_command(conf.receiver_arg[i], &arg);
 926                 if (ret < 0)
 927                         goto out;
 928                 af_mask = ret;
 929                 FOR_EACH_AUDIO_FORMAT(j) {
 930                         a = afi + j;
 931                         if ((af_mask & (1 << j)) == 0) /* no match */
 932                                 continue;
 933                         /*
 934                          * If multiple receivers are given for this audio format, the
 935                          * last one wins and we have to free the previous receiver
 936                          * config here. Since we are iterating backwards, the winning
 937                          * receiver arg is in fact the first one given.
 938                          */
 939                         if (a->receiver_conf)
 940                                 a->receiver->free_config(a->receiver_conf);
 941                         a->receiver_conf = check_receiver_arg(arg, &receiver_num);
 942                         ret = -E_RECV_SYNTAX;
 943                         if (!a->receiver_conf)
 944                                 goto out;
 945                         a->receiver = receivers + receiver_num;
 946                 }
 947         }
 948         /*
 949          * Use the first available receiver with no arguments for those audio
 950          * formats for which no receiver was specified.
 951          */
 952         cmd = para_strdup(receivers[0].name);
 953         FOR_EACH_AUDIO_FORMAT(i) {
 954                 a = &afi[i];
 955                 if (a->receiver_conf)
 956                         continue;
 957                 a->receiver_conf = check_receiver_arg(cmd, &receiver_num);
 958                 if (!a->receiver_conf)
 959                         return -E_RECV_SYNTAX;
 960                 a->receiver = &receivers[receiver_num];
 961         }
 962         FOR_EACH_AUDIO_FORMAT(i) {
 963                 a = afi + i;
 964                 PARA_INFO_LOG("receiving %s streams via %s receiver\n",
 965                         audio_formats[i], a->receiver->name);
 966         }
 967         ret = 1;
 968 out:
 969         free(cmd);
 970         return ret;
 971 }
 972
 973 static int init_default_filters(void)
 974 {
 975         int i, ret = 1;
 976
 977         FOR_EACH_AUDIO_FORMAT(i) {
 978                 struct audio_format_info *a = &afi[i];
 979                 char *tmp;
 980                 int j;
 981
 982                 if (a->num_filters)
 983                         continue; /* no default -- nothing to to */
 984                 /*
 985                  * udp and dccp streams are fec-encoded, so add fecdec as the
 986                  * first filter.
 987                  */
 988                 if (strcmp(afi[i].receiver->name, "udp") == 0 ||
 989                                 strcmp(afi[i].receiver->name, "dccp") == 0) {
 990                         tmp = para_strdup("fecdec");
 991                         add_filter(i, tmp);
 992                         free(tmp);
 993                         if (ret < 0)
 994                                 goto out;
 995                 }
 996                 /* add "dec" to audio format name */
 997                 tmp = make_message("%sdec", audio_formats[i]);
 998                 for (j = 0; filter_get(j); j++)
 999                         if (!strcmp(tmp, filter_get(j)->name))
1000                                 break;
1001                 free(tmp);
1002                 ret = -E_UNSUPPORTED_FILTER;
1003                 if (!filter_get(j))
1004                         goto out;
1005                 tmp = para_strdup(filter_get(j)->name);
1006                 ret = add_filter(i, tmp);
1007                 free(tmp);
1008                 if (ret < 0)
1009                         goto out;
1010                 PARA_INFO_LOG("%s -> default filter: %s\n", audio_formats[i],
1011                         filter_get(j)->name);
1012         }
1013 out:
1014         return ret;
1015 }
1016
1017 static int parse_filter_args(void)
1018 {
1019         int i, j, ret, af_mask, num_matches;
1020
1021         for (i = 0; i < conf.filter_given; i++) {
1022                 char *arg;
1023                 ret = parse_stream_command(conf.filter_arg[i], &arg);
1024                 if (ret < 0)
1025                         goto out;
1026                 af_mask = ret;
1027                 num_matches = 0;
1028                 FOR_EACH_AUDIO_FORMAT(j) {
1029                         if ((af_mask & (1 << j)) == 0) /* no match */
1030                                 continue;
1031                         ret = add_filter(j, arg);
1032                         if (ret < 0)
1033                                 goto out;
1034                         num_matches++;
1035                 }
1036                 if (num_matches == 0)
1037                         PARA_WARNING_LOG("ignoring filter spec: %s\n",
1038                                 conf.filter_arg[i]);
1039         }
1040         ret = init_default_filters(); /* use default values for the rest */
1041 out:
1042         return ret;
1043 }
1044
1045 static int parse_stream_args(void)
1046 {
1047         int ret;
1048
1049         ret = parse_receiver_args();
1050         if (ret < 0)
1051                 return ret;
1052         ret = parse_filter_args();
1053         if (ret < 0)
1054                 return ret;
1055         ret = parse_writer_args();
1056         if (ret < 0)
1057                 return ret;
1058         return 1;
1059 }
1060
1061 /* does not unlink socket on errors */
1062 static void init_local_sockets(struct command_task *ct)
1063 {
1064         if (conf.socket_given)
1065                 socket_name = para_strdup(conf.socket_arg);
1066         else {
1067                 char *hn = para_hostname();
1068                 socket_name = make_message("/var/paraslash/audiod_socket.%s",
1069                         hn);
1070                 free(hn);
1071         }
1072         PARA_NOTICE_LOG("local socket: %s\n", socket_name);
1073         if (conf.force_given)
1074                 unlink(socket_name);
1075         ct->fd[0] = create_local_socket(socket_name, 0);
1076         ct->fd[1] = create_local_socket(socket_name,
1077                 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
1078         if (ct->fd[0] >= 0 || ct->fd[1] >= 0)
1079                 return;
1080         PARA_EMERG_LOG("%s\n", para_strerror(-ct->fd[1]));
1081         exit(EXIT_FAILURE);
1082 }
1083
1084 static int signal_post_select(struct sched *s, void *context)
1085 {
1086         struct signal_task *st = context;
1087         int ret, signum;
1088
1089         ret = task_get_notification(st->task);
1090         if (ret < 0)
1091                 return ret;
1092         signum = para_next_signal(&s->rfds);
1093         switch (signum) {
1094         case SIGINT:
1095         case SIGTERM:
1096         case SIGHUP:
1097                 PARA_NOTICE_LOG("received signal %d\n", signum);
1098                 task_notify_all(s, E_AUDIOD_SIGNAL);
1099                 return -E_AUDIOD_SIGNAL;
1100         }
1101         return 0;
1102 }
1103
1104 static void command_pre_select(struct sched *s, void *context)
1105 {
1106         struct command_task *ct = context;
1107         int i;
1108
1109         for (i = 0; i < 2; i++)
1110                 if (ct->fd[i] >= 0)
1111                         para_fd_set(ct->fd[i], &s->rfds, &s->max_fileno);
1112 }
1113
1114 static int command_post_select(struct sched *s, void *context)
1115 {
1116         int ret, i;
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         for (i = 0; i < 2; i++) {
1126                 if (ct->fd[i] < 0)
1127                         continue;
1128                 ret = handle_connect(ct->fd[i], &s->rfds);
1129                 if (ret < 0) {
1130                         PARA_ERROR_LOG("%s\n", para_strerror(-ret));
1131                         if (ret == -E_AUDIOD_TERM) {
1132                                 task_notify_all(s, -ret);
1133                                 return ret;
1134                         }
1135                 } else if (ret > 0)
1136                         force = true;
1137         }
1138         if (force == true)
1139                 goto dump;
1140
1141         /* if last status dump was less than 500ms ago, do nothing */
1142         delay.tv_sec = 0;
1143         delay.tv_usec = 500 * 1000;
1144         tv_add(&last_status_dump, &delay, &tmp);
1145         if (tv_diff(now, &tmp, NULL) < 0)
1146                 return 0;
1147
1148         /*
1149          * If last status dump was more than 5s ago, force update. Otherwise,
1150          * update only those items that have changed.
1151          */
1152         delay.tv_sec = 5;
1153         delay.tv_usec = 0;
1154         tv_add(&last_status_dump, &delay, &tmp);
1155         if (tv_diff(now, &tmp, NULL) > 0)
1156                 force = true;
1157 dump:
1158         audiod_status_dump(force);
1159         last_status_dump = *now;
1160         return 1;
1161 }
1162
1163 static void init_command_task(struct command_task *ct)
1164 {
1165         init_local_sockets(ct); /* doesn't return on errors */
1166
1167         ct->task = task_register(&(struct task_info) {
1168                 .name = "command",
1169                 .pre_select = command_pre_select,
1170                 .post_select = command_post_select,
1171                 .context = ct,
1172         }, &sched);
1173 }
1174
1175 static void close_stat_pipe(void)
1176 {
1177         if (!stat_task->ct)
1178                 return;
1179         task_reap(&stat_task->ct->task);
1180         client_close(stat_task->ct);
1181         stat_task->ct = NULL;
1182         clear_and_dump_items();
1183         stat_task->length_seconds = 0;
1184         stat_task->offset_seconds = 0;
1185         stat_task->vss_status = 0;
1186         stat_task->current_audio_format_num = -1;
1187         audiod_status_dump(true);
1188 }
1189
1190 /* avoid busy loop if server is down */
1191 static void set_stat_task_restart_barrier(unsigned seconds)
1192 {
1193         struct timeval delay = {seconds, 0};
1194         tv_add(now, &delay, &stat_task->restart_barrier);
1195 }
1196
1197 static bool must_close_slot(int slot_num)
1198 {
1199         struct slot_info *s = &slot[slot_num];
1200         struct audio_format_info *a = afi + s->format;
1201         int i;
1202
1203         if (s->format < 0)
1204                 return false;
1205         if (s->receiver_node && task_status(s->receiver_node->task) >= 0)
1206                 return false;
1207         for (i = 0; i < a->num_filters; i++)
1208                 if (s->fns && task_status(s->fns[i].task) >= 0)
1209                         return false;
1210         if (a->num_writers > 0) {
1211                 for (i = 0; i < a->num_writers; i++)
1212                         if (s->wns && task_status(s->wns[i].task) >= 0)
1213                                 return false;
1214         } else {
1215                 if (s->wns && task_status(s->wns[0].task) >= 0)
1216                         return false;
1217         }
1218         return true;
1219 }
1220
1221 static void close_slot(int slot_num)
1222 {
1223         struct slot_info *s = slot + slot_num;
1224
1225         PARA_INFO_LOG("closing slot %d\n", slot_num);
1226         close_writers(s);
1227         close_filters(s);
1228         close_receiver(slot_num);
1229         clear_slot(slot_num);
1230 }
1231
1232 static void close_unused_slots(void)
1233 {
1234         int i;
1235         bool dump = false;
1236
1237         FOR_EACH_SLOT(i)
1238                 if (must_close_slot(i)) {
1239                         close_slot(i);
1240                         dump = true;
1241                 }
1242         if (dump)
1243                 audiod_status_dump(true);
1244 }
1245
1246 /*
1247  * Cleanup all resources.
1248  *
1249  * This performs various cleanups, removes the audiod socket and closes the
1250  * connection to para_server.
1251  */
1252 static void audiod_cleanup(void)
1253 {
1254         if (socket_name)
1255                 unlink(socket_name);
1256         close_stat_pipe();
1257         close_unused_slots();
1258         audiod_cmdline_parser_free(&conf);
1259         close_stat_clients();
1260         free(uid_whitelist);
1261 }
1262
1263 /*
1264  * Check if any receivers/filters/writers need to be started and do so if
1265  * necessary.
1266  */
1267 static void start_stop_decoders(void)
1268 {
1269         int ret;
1270         struct slot_info *sl;
1271
1272         close_unused_slots();
1273         if (audiod_status != AUDIOD_ON ||
1274                         !(stat_task->vss_status & VSS_STATUS_FLAG_PLAYING))
1275                 return notify_receivers(E_NOT_PLAYING);
1276         if (!must_start_decoder())
1277                 return;
1278         ret = open_receiver(stat_task->current_audio_format_num);
1279         if (ret < 0) {
1280                 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
1281                 return;
1282         }
1283         sl = slot + ret;
1284         open_filters(sl);
1285         open_writers(sl);
1286         activate_grab_clients(&sched);
1287         btr_log_tree(sl->receiver_node->btrn, LL_NOTICE);
1288         audiod_status_dump(true);
1289 }
1290
1291 static void status_pre_select(struct sched *s, void *context)
1292 {
1293         struct status_task *st = context;
1294         int i, ret, cafn = stat_task->current_audio_format_num;
1295
1296         if (must_start_decoder())
1297                 goto min_delay;
1298         FOR_EACH_SLOT(i)
1299                 if (must_close_slot(i))
1300                         goto min_delay;
1301         ret = btr_node_status(st->btrn, st->min_iqs, BTR_NT_LEAF);
1302         if (ret > 0)
1303                 goto min_delay;
1304         if (st->ct && audiod_status == AUDIOD_OFF)
1305                 goto min_delay;
1306         if (!st->ct && audiod_status != AUDIOD_OFF)
1307                 sched_request_barrier_or_min_delay(&st->restart_barrier, s);
1308         if (cafn >= 0)
1309                 sched_request_barrier(&afi[cafn].restart_barrier, s);
1310         /*
1311          * If para_server is playing we'd like to have a smooth time display
1312          * even if we are running in standby mode. So we request a timeout that
1313          * expires at the next full second.
1314          */
1315         if (stat_task->vss_status & VSS_STATUS_FLAG_PLAYING)
1316                 sched_request_timeout_ms(1000 - now->tv_usec / 1000, s);
1317         return;
1318 min_delay:
1319         sched_min_delay(s);
1320 }
1321
1322 /* restart the client task if necessary */
1323 static int status_post_select(struct sched *s, void *context)
1324 {
1325         struct status_task *st = context;
1326         int ret;
1327
1328         ret = task_get_notification(st->task);
1329         if (ret < 0)
1330                 return ret;
1331         if (audiod_status == AUDIOD_OFF) {
1332                 if (!st->ct)
1333                         goto out;
1334                 if (task_status(st->ct->task) >= 0) {
1335                         task_notify(st->ct->task, E_AUDIOD_OFF);
1336                         goto out;
1337                 }
1338                 close_stat_pipe();
1339                 st->clock_diff_count = conf.clock_diff_count_arg;
1340                 goto out;
1341         }
1342         if (st->ct) {
1343                 char *buf;
1344                 size_t sz;
1345
1346                 ret = btr_node_status(st->btrn, st->min_iqs, BTR_NT_LEAF);
1347                 if (ret < 0) {
1348                         close_stat_pipe();
1349                         goto out;
1350                 }
1351                 if (st->ct->status != CL_EXECUTING)
1352                         goto out;
1353                 if (ret == 0) {
1354                         struct timeval diff;
1355                         tv_diff(now, &st->last_status_read, &diff);
1356                         if (diff.tv_sec > 61)
1357                                 task_notify(st->ct->task, E_STATUS_TIMEOUT);
1358                         goto out;
1359                 }
1360                 btr_merge(st->btrn, st->min_iqs);
1361                 sz = btr_next_buffer(st->btrn, &buf);
1362                 ret = for_each_stat_item(buf, sz, update_item);
1363                 if (ret < 0) {
1364                         task_notify(st->ct->task, -ret);
1365                         goto out;
1366                 }
1367                 if (sz != ret) {
1368                         btr_consume(st->btrn, sz - ret);
1369                         st->last_status_read = *now;
1370                         st->min_iqs = 0;
1371                 } else /* current status item crosses buffers */
1372                         st->min_iqs = sz + 1;
1373                 goto out;
1374         }
1375         btr_drain(st->btrn);
1376         st->current_audio_format_num = -1;
1377         if (tv_diff(now, &st->restart_barrier, NULL) < 0)
1378                 goto out;
1379         if (st->clock_diff_count) { /* get status only one time */
1380                 char *argv[] = {"audiod", "--", "stat", "-p", "-n=1", NULL};
1381                 int argc = 5;
1382                 PARA_INFO_LOG("clock diff count: %u\n", st->clock_diff_count);
1383                 st->clock_diff_count--;
1384                 client_open(argc, argv, &st->ct, NULL, NULL, st->btrn, s);
1385                 set_stat_task_restart_barrier(2);
1386
1387         } else {
1388                 char *argv[] = {"audiod", "--", "stat", "-p", NULL};
1389                 int argc = 4;
1390                 client_open(argc, argv, &st->ct, NULL, NULL, st->btrn, s);
1391                 set_stat_task_restart_barrier(5);
1392         }
1393         free(stat_item_values[SI_BASENAME]);
1394         stat_item_values[SI_BASENAME] = para_strdup(
1395                 "no connection to para_server");
1396         stat_client_write_item(SI_BASENAME);
1397         st->last_status_read = *now;
1398 out:
1399         start_stop_decoders();
1400         return 0;
1401 }
1402
1403 static void init_status_task(struct status_task *st)
1404 {
1405         memset(st, 0, sizeof(struct status_task));
1406         st->sa_time_diff_sign = 1;
1407         st->clock_diff_count = conf.clock_diff_count_arg;
1408         st->current_audio_format_num = -1;
1409         st->btrn = btr_new_node(&(struct btr_node_description)
1410                 EMBRACE(.name = "stat"));
1411
1412         stat_task->task = task_register(&(struct task_info) {
1413                 .name = "stat",
1414                 .pre_select = status_pre_select,
1415                 .post_select = status_post_select,
1416                 .context = stat_task,
1417         }, &sched);
1418 }
1419
1420 static void set_initial_status(void)
1421 {
1422         audiod_status = AUDIOD_ON;
1423         if (!conf.mode_given)
1424                 return;
1425         if (!strcmp(conf.mode_arg, "sb")) {
1426                 audiod_status = AUDIOD_STANDBY;
1427                 return;
1428         }
1429         if (!strcmp(conf.mode_arg, "off")) {
1430                 audiod_status = AUDIOD_OFF;
1431                 return;
1432         }
1433         if (strcmp(conf.mode_arg, "on"))
1434                 PARA_WARNING_LOG("invalid mode\n");
1435 }
1436
1437 __noreturn static void print_help_and_die(void)
1438 {
1439         struct ggo_help h = DEFINE_GGO_HELP(audiod);
1440         bool d = conf.detailed_help_given;
1441         unsigned flags;
1442
1443         flags = d? GPH_STANDARD_FLAGS_DETAILED : GPH_STANDARD_FLAGS;
1444         ggo_print_help(&h, flags);
1445
1446         flags = d? GPH_MODULE_FLAGS_DETAILED : GPH_MODULE_FLAGS;
1447         print_receiver_helps(flags);
1448         print_filter_helps(flags);
1449         print_writer_helps(flags);
1450         exit(0);
1451 }
1452
1453 /**
1454  * Lookup the given UID in the whitelist.
1455  *
1456  * The whitelist is the array of arguments to the --user-allow opion. If the
1457  * option was not given, the array is empty, in which case the check succeeds.
1458  *
1459  * \param uid User ID to look up.
1460  *
1461  * \return True if --user-allow was not given, or if uid matches an element of
1462  * the whitelist.
1463  */
1464 bool uid_is_whitelisted(uid_t uid)
1465 {
1466         int i;
1467
1468         if (!conf.user_allow_given)
1469                 return true;
1470         for (i = 0; i < conf.user_allow_given; i++)
1471                 if (uid == uid_whitelist[i])
1472                         return true;
1473         return false;
1474 }
1475
1476 /**
1477  * the main function of para_audiod
1478  *
1479  * \param argc usual argument count
1480  * \param argv usual argument vector
1481  *
1482  * \return EXIT_SUCCESS or EXIT_FAILURE
1483  *
1484  * \sa para_audiod(1)
1485  * */
1486 int main(int argc, char *argv[])
1487 {
1488         int ret, i;
1489         struct command_task command_task_struct, *cmd_task = &command_task_struct;
1490         struct audiod_cmdline_parser_params params = {
1491                 .override = 0,
1492                 .initialize = 1,
1493                 .check_required = 0,
1494                 .check_ambiguity = 0,
1495                 .print_errors = 1
1496         };
1497
1498         valid_fd_012();
1499         audiod_cmdline_parser_ext(argc, argv, &conf, &params);
1500         daemon_set_loglevel(conf.loglevel_arg);
1501         version_handle_flag("audiod", conf.version_given);
1502         /* init receivers/filters/writers early to make help work */
1503         recv_init();
1504         filter_init();
1505         writer_init();
1506         if (conf.help_given || conf.detailed_help_given)
1507                 print_help_and_die();
1508         daemon_set_priority(conf.priority_arg);
1509         daemon_drop_privileges_or_die(conf.user_arg, conf.group_arg);
1510         parse_config_or_die();
1511         if (daemon_init_colors_or_die(conf.color_arg, color_arg_auto, color_arg_no,
1512                 conf.logfile_given)) {
1513                         for (i = 0; i < conf.log_color_given; i++)
1514                                 daemon_set_log_color_or_die(conf.log_color_arg[i]);
1515         }
1516         init_random_seed_or_die();
1517         daemon_set_flag(DF_LOG_TIME);
1518         daemon_set_flag(DF_LOG_HOSTNAME);
1519         daemon_set_flag(DF_LOG_LL);
1520         if (conf.log_timing_given)
1521                 daemon_set_flag(DF_LOG_TIMING);
1522         if (conf.logfile_given) {
1523                 daemon_set_logfile(conf.logfile_arg);
1524                 daemon_open_log_or_die();
1525         }
1526         ret = parse_stream_args();
1527         if (ret < 0) {
1528                 PARA_EMERG_LOG("%s\n", para_strerror(-ret));
1529                 exit(EXIT_FAILURE);
1530         }
1531         daemon_log_welcome("audiod");
1532         daemon_set_start_time();
1533         set_initial_status();
1534         FOR_EACH_SLOT(i)
1535                 clear_slot(i);
1536         setup_signal_handling();
1537
1538         init_status_task(stat_task);
1539         init_command_task(cmd_task);
1540
1541         if (conf.daemon_given)
1542                 daemonize(false /* parent exits immediately */);
1543
1544         signal_task->task = task_register(&(struct task_info) {
1545                 .name = "signal",
1546                 .pre_select = signal_pre_select,
1547                 .post_select = signal_post_select,
1548                 .context = signal_task,
1549         }, &sched);
1550
1551         sched.default_timeout.tv_sec = 2;
1552         sched.default_timeout.tv_usec = 999 * 1000;
1553         ret = schedule(&sched);
1554         audiod_cleanup();
1555         sched_shutdown(&sched);
1556         signal_shutdown(signal_task);
1557
1558         if (ret < 0)
1559                 PARA_EMERG_LOG("%s\n", para_strerror(-ret));
1560         return ret < 0? EXIT_FAILURE : EXIT_SUCCESS;
1561 }