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 __printf_2_3 void (*para_log)(int, const char*, ...) = daemon_log;
  43 /** define the array of error lists needed by para_audiod */
  44 INIT_AUDIOD_ERRLISTS;
  45 /** define the array containing all supported audio formats */
  46 const char *audio_formats[] = {AUDIOD_AUDIO_FORMAT_ARRAY NULL};
  47
  48 DEFINE_RECEIVER_ARRAY;
  49
  50 /** Defines how audiod handles one supported audio format. */
  51 struct audio_format_info {
  52         /** pointer to the receiver for this audio format */
  53         struct receiver *receiver;
  54         /** the receiver configuration */
  55         void *receiver_conf;
  56         /** the number of filters that should be activated for this audio format */
  57         unsigned int num_filters;
  58         /** Array of filter numbers to be activated. */
  59         unsigned *filter_nums;
  60         /** Pointer to the array of filter configurations. */
  61         void **filter_conf;
  62         /** the number of filters that should be activated for this audio format */
  63         unsigned int num_writers;
  64         /** Array of writer numbers to be activated. */
  65         int *writer_nums;
  66         /** pointer to the array of writer configurations */
  67         void **writer_conf;
  68         /** do not start receiver/filters/writer before this time */
  69         struct timeval restart_barrier;
  70 };
  71
  72 /* Describes one instance of a receiver-filter-writer chain. */
  73 struct slot_info {
  74         /* Number of the audio format in this slot. */
  75         int format;
  76         /* The stream_start status item announced by para_server.  */
  77         struct timeval server_stream_start;
  78         /* The offset status item announced by para_server. */
  79         unsigned offset_seconds;
  80         /* The seconds_total status item announced by para_server. */
  81         unsigned seconds_total;
  82         /* The receiver info associated with this slot. */
  83         struct receiver_node *receiver_node;
  84         /* The array of filter nodes. */
  85         struct filter_node *fns;
  86         /* The array of writers attached to the last filter. */
  87         struct writer_node *wns;
  88 };
  89
  90 /** Maximal number of simultaneous instances. */
  91 #define MAX_STREAM_SLOTS 5
  92
  93 /** Iterate over all slots. */
  94 #define FOR_EACH_SLOT(_slot) for (_slot = 0; _slot < MAX_STREAM_SLOTS; _slot++)
  95
  96 /**
  97  * para_audiod uses \p MAX_STREAM_SLOTS different slots, each of which may
  98  * be associated with a receiver/filter/writer triple. This array holds all
  99  * information on the status of these slots.
 100  *
 101  * \sa struct slot_info
 102  * */
 103 struct slot_info slot[MAX_STREAM_SLOTS];
 104
 105 /** The vss status flags audiod is interested in. */
 106 enum vss_status_flags {
 107         /** Whether the 'N' flag is set. */
 108         VSS_STATUS_FLAG_NEXT = 1,
 109         /** The 'P' flag is set. */
 110         VSS_STATUS_FLAG_PLAYING = 2,
 111 };
 112
 113 /**
 114  * The scheduler instance of para_audiod.
 115  *
 116  * This is needed also in audiod_command.c (for the tasks command), so it can
 117  * not be made static.
 118  */
 119 struct sched sched = {.max_fileno = 0};
 120
 121 /* The task for obtaining para_server's status (para_client stat). */
 122 struct status_task {
 123         /** The associated task structure of audiod. */
 124         struct task *task;
 125         /** Client data associated with the stat task. */
 126         struct client_task *ct;
 127         /** Do not restart client command until this time. */
 128         struct timeval restart_barrier;
 129         /** Last time we received status data from para_server. */
 130         struct timeval last_status_read;
 131         size_t min_iqs;
 132         /** The offset value announced by para_server. */
 133         int offset_seconds;
 134         /** The length of the current audio file as announced by para_server. */
 135         int length_seconds;
 136         /** The start of the current stream from the view of para_server. */
 137         struct timeval server_stream_start;
 138         /** The average time deviation between para_server and para_audiod. */
 139         struct timeval sa_time_diff;
 140         /** Whether client time is ahead of server time. */
 141         int sa_time_diff_sign;
 142         /** The 'P' and the 'N' flags as announced by para_server. */
 143         enum vss_status_flags vss_status;
 144         /** Number of times the clock difference is to be checked. */
 145         unsigned clock_diff_count;
 146         /** When to start the next check for clock difference. */
 147         struct timeval clock_diff_barrier;
 148         /** Number of the audio format as announced by para_server. */
 149         int current_audio_format_num;
 150         /* The status task btrn is the child of the client task. */
 151         struct btr_node *btrn;
 152 };
 153
 154 /** The array of status items sent by para_server. */
 155 char *stat_item_values[NUM_STAT_ITEMS] = {NULL};
 156
 157 /**
 158  * the current mode of operation of which can be changed by the on/off/cycle
 159  * commands. It is either, AUDIOD_OFF, AUDIOD_ON or AUDIOD_STANDBY.
 160  */
 161 int audiod_status = AUDIOD_ON;
 162
 163 /**
 164  * the gengetopt args_info struct that holds information on all command line
 165  * arguments
 166  */
 167 struct audiod_args_info conf;
 168
 169 static char *socket_name;
 170 static struct audio_format_info afi[NUM_AUDIO_FORMATS];
 171
 172 static struct signal_task *signal_task;
 173
 174 static struct status_task status_task_struct;
 175
 176 static uid_t *uid_whitelist;
 177
 178 /**
 179  * the task that calls the status command of para_server
 180  *
 181  * \sa struct status_task
 182  */
 183 static struct status_task *stat_task = &status_task_struct;
 184
 185 /*
 186  * The task for handling audiod commands.
 187  *
 188  * We need two listening sockets for backward compability: on Linux systems
 189  * fd[0] is an abstract socket (more precisely, a socket bound to an address in
 190  * the abstract namespace), and fd[1] is the usual pathname socket. On other
 191  * systems, fd[0] is negative, and only the pathname socket is used.
 192  *
 193  * For 0.5.x we accept connections on both sockets to make sure that old
 194  * para_audioc versions can still connect. New versions use only the abstract
 195  * socket. Hence after v0.6.0 we can go back to a single socket, either an
 196  * abstract one (Linux) or a pathname socket (all other systems).
 197  */
 198 struct command_task {
 199         /** The local listening sockets. */
 200         int fd[2];
 201         /** the associated task structure */
 202         struct task *task;
 203 };
 204
 205 /** iterate over all supported audio formats */
 206 #define FOR_EACH_AUDIO_FORMAT(af) for (af = 0; af < NUM_AUDIO_FORMATS; af++)
 207
 208 /**
 209  * Get the audio format number.
 210  *
 211  * \param name The name of the audio format.
 212  *
 213  * \return The audio format number on success, -E_UNSUPPORTED_AUDIO_FORMAT if
 214  * \a name is not a supported audio format.
 215  */
 216 static int get_audio_format_num(const char *name)
 217 {
 218         int i;
 219
 220         while (para_isspace(*name))
 221                 name++;
 222         FOR_EACH_AUDIO_FORMAT(i)
 223                 if (!strcmp(name, audio_formats[i]))
 224                         return i;
 225         return -E_UNSUPPORTED_AUDIO_FORMAT;
 226 }
 227
 228 /**
 229  * Return the flags for the \a decoder_flags status item.
 230  *
 231  * Allocates a string which contains one octal digit per slot.  Bit zero (value
 232  * 1) is set if a receiver is active. Bit one (value 2) and bit three (value 4)
 233  * have the analogous meaning for filter and writer, respectively.
 234  *
 235  * \return String that must be freed by the caller.
 236  */
 237 __malloc char *audiod_get_decoder_flags(void)
 238 {
 239         int i;
 240         char flags[MAX_STREAM_SLOTS + 1];
 241
 242         FOR_EACH_SLOT(i) {
 243                 struct slot_info *s = &slot[i];
 244                 char flag = '0';
 245                 if (s->receiver_node)
 246                         flag += 1;
 247                 if (s->fns)
 248                         flag += 2;
 249                 if (s->wns)
 250                         flag += 4;
 251                 flags[i] = flag;
 252         }
 253         flags[MAX_STREAM_SLOTS] = '\0';
 254         return para_strdup(flags);
 255 }
 256
 257 static int get_matching_audio_format_nums(const char *re)
 258 {
 259         int i, ret;
 260         regex_t preg;
 261
 262         ret = para_regcomp(&preg, re, REG_EXTENDED | REG_NOSUB);
 263         if (ret < 0)
 264                 return ret;
 265         ret = 0;
 266         FOR_EACH_AUDIO_FORMAT(i)
 267                 if (regexec(&preg, audio_formats[i], 0, NULL, 0) != REG_NOMATCH)
 268                         ret |= (1 << i);
 269         regfree(&preg);
 270         return ret;
 271 }
 272
 273 static int get_play_time_slot_num(void)
 274 {
 275         int i, oldest_slot = -1;
 276         struct timeval oldest_wstime = {0, 0};
 277
 278         FOR_EACH_SLOT(i) {
 279                 struct slot_info *s = &slot[i];
 280                 struct timeval wstime;
 281                 if (!s->wns || !s->wns[0].btrn)
 282                         continue;
 283                 btr_get_node_start(s->wns[0].btrn, &wstime);
 284                 if (oldest_slot >= 0 && tv_diff(&wstime, &oldest_wstime, NULL) > 0)
 285                         continue;
 286                 oldest_wstime = wstime;
 287                 oldest_slot = i;
 288         }
 289         return oldest_slot;
 290 }
 291
 292 /**
 293  * Compute the play time based on information of the current slot.
 294  *
 295  * This computes a string of the form "0:07 [3:33] (3%/3:40)" using information
 296  * from the status items received from para_server and the start time of the
 297  * (first) writer of the current slot.
 298  *
 299  * It has to take into account that the stream was probably not started at
 300  * the beginning of the file, that the clock between the server and the client
 301  * host may differ and that playback of the stream was delayed, e.g. because
 302  * the prebuffer filter is used in the filter configuration.
 303  *
 304  * If no writer is active, for example because para_audiod runs in standby
 305  * mode, an approximation based only on the status items is computed and the
 306  * returned string is prefixed with "~".
 307  *
 308  * \return A string that must be freed by the caller.
 309  */
 310 char *get_time_string(void)
 311 {
 312         int ret, seconds = 0, length;
 313         struct timeval *tmp, sum, sss, /* server stream start */
 314                 rstime, /* receiver start time */
 315                 wstime, /* writer start time */
 316                 wtime, /* now - writer start */
 317                 rskip; /* receiver start - sss */
 318         int slot_num = get_play_time_slot_num();
 319         struct slot_info *s = slot_num < 0? NULL : &slot[slot_num];
 320         char *msg;
 321
 322         if (audiod_status == AUDIOD_OFF)
 323                 goto empty;
 324         if (!(stat_task->vss_status & VSS_STATUS_FLAG_PLAYING)) {
 325                 if (stat_task->length_seconds) /* paused */
 326                         return NULL;
 327                 goto empty; /* stopped */
 328         }
 329         if (audiod_status == AUDIOD_ON && !s)
 330                 goto empty;
 331         /*
 332          * Valid status items and playing, set length and tmp to the stream
 333          * start. We use the slot info and fall back to the info from current
 334          * status items if no slot info is available.
 335          */
 336         length = stat_task->length_seconds;
 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) {
 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) { /* audiod was started in the middle of the stream */
 368                         tv_add(&wtime, &rskip, &sum);
 369                         seconds += sum.tv_sec;
 370                 } else
 371                         seconds += wtime.tv_sec;
 372         } else
 373                 seconds += wtime.tv_sec;
 374 out:
 375         seconds = PARA_MIN(seconds, length);
 376         seconds = PARA_MAX(seconds, 0);
 377         msg = make_message(
 378                 "%s%d:%02d [%d:%02d] (%d%%/%d:%02d)",
 379                 s? "" : "~",
 380                 seconds / 60,
 381                 seconds % 60,
 382                 (length - seconds) / 60,
 383                 (length - seconds) % 60,
 384                 length? (seconds * 100 + length / 2) / length : 0,
 385                 length / 60,
 386                 length % 60
 387         );
 388         //PARA_DEBUG_LOG("slot %d: %s\n", slot_num, msg);
 389         return msg;
 390 empty:
 391         return para_strdup(NULL);
 392 }
 393
 394 static void parse_config_or_die(void)
 395 {
 396         int ret, i;
 397         char *config_file;
 398         struct audiod_cmdline_parser_params params = {
 399                 .override = 0,
 400                 .initialize = 0,
 401                 .check_required = 1,
 402                 .check_ambiguity = 0,
 403                 .print_errors = 1
 404         };
 405
 406         if (conf.config_file_given)
 407                 config_file = para_strdup(conf.config_file_arg);
 408         else {
 409                 char *home = para_homedir();
 410                 config_file = make_message("%s/.paraslash/audiod.conf", home);
 411                 free(home);
 412         }
 413         ret = file_exists(config_file);
 414         if (conf.config_file_given && !ret) {
 415                 PARA_EMERG_LOG("can not read config file %s\n", config_file);
 416                 free(config_file);
 417                 goto err;
 418         }
 419         if (ret) {
 420                 audiod_cmdline_parser_config_file(config_file, &conf, &params);
 421                 daemon_set_loglevel(conf.loglevel_arg);
 422         }
 423         free(config_file);
 424         if (conf.user_allow_given > 0) {
 425                 uid_whitelist = para_malloc(conf.user_allow_given
 426                         * sizeof(uid_t));
 427                 for (i = 0; i < conf.user_allow_given; i++) {
 428                         int32_t val;
 429                         struct passwd *pw;
 430                         ret = para_atoi32(conf.user_allow_arg[i], &val);
 431                         if (ret >= 0) {
 432                                 uid_whitelist[i] = val;
 433                                 continue;
 434                         }
 435                         errno = 0; /* see getpwnam(3) */
 436                         pw = getpwnam(conf.user_allow_arg[i]);
 437                         if (!pw) {
 438                                 PARA_EMERG_LOG("invalid username: %s\n",
 439                                         conf.user_allow_arg[i]);
 440                                 goto err;
 441                         }
 442                         uid_whitelist[i] = pw->pw_uid;
 443                 }
 444         }
 445         return;
 446 err:
 447         exit(EXIT_FAILURE);
 448 }
 449
 450 static void setup_signal_handling(void)
 451 {
 452         signal_task = signal_init_or_die();
 453         para_install_sighandler(SIGINT);
 454         para_install_sighandler(SIGTERM);
 455         para_install_sighandler(SIGHUP);
 456         para_sigaction(SIGPIPE, SIG_IGN);
 457 }
 458
 459 static void clear_slot(int slot_num)
 460 {
 461         struct slot_info *s = &slot[slot_num];
 462
 463         PARA_INFO_LOG("clearing slot %d\n", slot_num);
 464         memset(s, 0, sizeof(struct slot_info));
 465         s->format = -1;
 466 }
 467
 468 static void close_receiver(int slot_num)
 469 {
 470         struct slot_info *s = &slot[slot_num];
 471         struct audio_format_info *a;
 472
 473         if (s->format < 0 || !s->receiver_node)
 474                 return;
 475         a = &afi[s->format];
 476         PARA_NOTICE_LOG("closing %s receiver in slot %d\n",
 477                 audio_formats[s->format], slot_num);
 478         a->receiver->close(s->receiver_node);
 479         btr_remove_node(&s->receiver_node->btrn);
 480         task_reap(&s->receiver_node->task);
 481         free(s->receiver_node);
 482         s->receiver_node = NULL;
 483         stat_task->current_audio_format_num = -1;
 484         tv_add(now, &(struct timeval)EMBRACE(0, 200 * 1000),
 485                 &a->restart_barrier);
 486 }
 487
 488 static void writer_cleanup(struct writer_node *wn)
 489 {
 490         struct writer *w;
 491
 492         if (!wn)
 493                 return;
 494         w = writers + wn->writer_num;
 495         PARA_INFO_LOG("closing %s\n", writer_names[wn->writer_num]);
 496         w->close(wn);
 497         btr_remove_node(&wn->btrn);
 498         task_reap(&wn->task);
 499 }
 500
 501 static void close_writers(struct slot_info *s)
 502 {
 503         struct audio_format_info *a;
 504         int i;
 505
 506         if (s->format < 0)
 507                 return;
 508         assert(s->wns);
 509         a = afi + s->format;
 510         if (a->num_writers == 0)
 511                 writer_cleanup(s->wns);
 512         else {
 513                 for (i = 0; i < a->num_writers; i++)
 514                         writer_cleanup(s->wns + i);
 515         }
 516         free(s->wns);
 517         s->wns = NULL;
 518 }
 519
 520 static void close_filters(struct slot_info *s)
 521 {
 522         int i;
 523         struct audio_format_info *a = afi + s->format;
 524         if (a->num_filters == 0)
 525                 return;
 526         for (i = a->num_filters - 1; i >= 0; i--) {
 527                 struct filter_node *fn = s->fns + i;
 528                 struct filter *f;
 529
 530                 if (!fn)
 531                         continue;
 532                 f = filters + fn->filter_num;
 533                 if (f->close)
 534                         f->close(fn);
 535                 btr_remove_node(&fn->btrn);
 536                 task_reap(&fn->task);
 537         }
 538         free(s->fns);
 539         s->fns = NULL;
 540 }
 541
 542 static void notify_receivers(int error)
 543 {
 544         int i;
 545
 546         FOR_EACH_SLOT(i) {
 547                 struct slot_info *s = slot + i;
 548                 if (s->format < 0)
 549                         continue;
 550                 if (!s->receiver_node)
 551                         continue;
 552                 task_notify(s->receiver_node->task, error);
 553         }
 554 }
 555
 556 static int get_empty_slot(void)
 557 {
 558         int i;
 559         struct slot_info *s;
 560
 561         FOR_EACH_SLOT(i) {
 562                 s = &slot[i];
 563                 if (s->format < 0) {
 564                         clear_slot(i);
 565                         return i;
 566                 }
 567                 if (s->wns || s->receiver_node || s->fns)
 568                         continue;
 569                 clear_slot(i);
 570                 return i;
 571         }
 572         return -E_NO_MORE_SLOTS;
 573 }
 574
 575 static void open_filters(struct slot_info *s)
 576 {
 577         struct audio_format_info *a = afi + s->format;
 578         struct filter_node *fn;
 579         int nf = a->num_filters;
 580         struct btr_node *parent;
 581         int i;
 582
 583         if (nf == 0)
 584                 return;
 585         PARA_INFO_LOG("opening %s filters\n", audio_formats[s->format]);
 586         assert(s->fns == NULL);
 587         s->fns = para_calloc(nf * sizeof(struct filter_node));
 588         parent = s->receiver_node->btrn;
 589         for (i = 0; i < nf; i++) {
 590                 char buf[20];
 591                 struct filter *f = filters + a->filter_nums[i];
 592                 fn = s->fns + i;
 593                 fn->filter_num = a->filter_nums[i];
 594                 fn->conf = a->filter_conf[i];
 595                 fn->btrn = btr_new_node(&(struct btr_node_description)
 596                         EMBRACE(.name = f->name, .parent = parent,
 597                                 .handler = f->execute, .context = fn));
 598
 599                 f->open(fn);
 600                 sprintf(buf, "%s (slot %d)", f->name, (int)(s - slot));
 601                 fn->task = task_register(&(struct task_info) {
 602                         .name = buf,
 603                         .pre_select = f->pre_select,
 604                         .post_select = f->post_select,
 605                         .context = fn,
 606                 }, &sched);
 607                 parent = fn->btrn;
 608                 PARA_NOTICE_LOG("%s filter %d/%d (%s) started in slot %d\n",
 609                         audio_formats[s->format], i,  nf, f->name, (int)(s - slot));
 610         }
 611 }
 612
 613 static void open_writers(struct slot_info *s)
 614 {
 615         int i;
 616         struct audio_format_info *a = afi + s->format;
 617         struct writer_node *wn;
 618         struct btr_node *parent = s->fns[a->num_filters - 1].btrn;
 619
 620         assert(s->wns == NULL);
 621         s->wns = para_calloc(PARA_MAX(1U, a->num_writers)
 622                 * sizeof(struct writer_node));
 623         for (i = 0; i < a->num_writers; i++) {
 624                 wn = s->wns + i;
 625                 wn->conf = a->writer_conf[i];
 626                 wn->writer_num = a->writer_nums[i];
 627                 register_writer_node(wn, parent, &sched);
 628                 PARA_NOTICE_LOG("%s writer started in slot %d\n",
 629                         writer_names[a->writer_nums[i]], (int)(s - slot));
 630         }
 631 }
 632
 633 /* returns slot num on success */
 634 static int open_receiver(int format)
 635 {
 636         struct audio_format_info *a = &afi[format];
 637         struct slot_info *s;
 638         int ret, slot_num;
 639         struct receiver *r = a->receiver;
 640         struct receiver_node *rn;
 641
 642         tv_add(now, &(struct timeval)EMBRACE(2, 0), &a->restart_barrier);
 643         ret = get_empty_slot();
 644         if (ret < 0)
 645                 return ret;
 646         slot_num = ret;
 647         rn = para_calloc(sizeof(*rn));
 648         rn->receiver = r;
 649         rn->conf = a->receiver_conf;
 650         rn->btrn = btr_new_node(&(struct btr_node_description)
 651                 EMBRACE(.name = r->name, .context = rn));
 652         ret = r->open(rn);
 653         if (ret < 0) {
 654                 btr_remove_node(&rn->btrn);
 655                 free(rn);
 656                 return ret;
 657         }
 658         s = &slot[slot_num];
 659         s->format = format;
 660         s->receiver_node = rn;
 661         PARA_NOTICE_LOG("started %s: %s receiver in slot %d\n",
 662                 audio_formats[format], r->name, slot_num);
 663         rn->task = task_register(&(struct task_info) {
 664                 .name = r->name,
 665                 .pre_select = r->pre_select,
 666                 .post_select = r->post_select,
 667                 .context = rn,
 668         }, &sched);
 669         return slot_num;
 670 }
 671
 672 static bool receiver_running(void)
 673 {
 674         int i;
 675         long unsigned ss1 = stat_task->server_stream_start.tv_sec;
 676
 677         FOR_EACH_SLOT(i) {
 678                 struct slot_info *s = &slot[i];
 679                 long unsigned ss2 = s->server_stream_start.tv_sec;
 680
 681                 if (!s->receiver_node)
 682                         continue;
 683                 if (task_status(s->receiver_node->task) >= 0)
 684                         return true;
 685                 if (ss1 == ss2)
 686                         return true;
 687         }
 688         return false;
 689 }
 690
 691 /**
 692  * Return the root node of the current buffer tree.
 693  *
 694  * This is only used for stream grabbing.
 695  *
 696  * \return \p NULL if no slot is currently active. If more than one buffer tree
 697  * exists, the node corresponding to the most recently started receiver is
 698  * returned.
 699  */
 700 struct btr_node *audiod_get_btr_root(void)
 701 {
 702         int i, newest_slot = -1;
 703         struct timeval newest_rstime = {0, 0};
 704
 705         FOR_EACH_SLOT(i) {
 706                 struct slot_info *s = &slot[i];
 707                 struct timeval rstime;
 708                 if (!s->receiver_node)
 709                         continue;
 710                 if (task_status(s->receiver_node->task) < 0)
 711                         continue;
 712                 btr_get_node_start(s->receiver_node->btrn, &rstime);
 713                 if (newest_slot >= 0 && tv_diff(&rstime, &newest_rstime, NULL) < 0)
 714                         continue;
 715                 newest_rstime = rstime;
 716                 newest_slot = i;
 717         }
 718         if (newest_slot == -1)
 719                 return NULL;
 720         return slot[newest_slot].receiver_node->btrn;
 721 }
 722
 723 /* whether a new instance of a decoder should be started. */
 724 static bool must_start_decoder(void)
 725 {
 726         int cafn = stat_task->current_audio_format_num;
 727         unsigned vs = stat_task->vss_status;
 728
 729         if (audiod_status != AUDIOD_ON)
 730                 return false;
 731         if (cafn < 0)
 732                 return false;
 733         if (!stat_task->ct)
 734                 return false;
 735         if (vs & VSS_STATUS_FLAG_NEXT)
 736                 return false;
 737         if (!(vs & VSS_STATUS_FLAG_PLAYING))
 738                 return false;
 739         if (receiver_running())
 740                 return false;
 741         if (tv_diff(now, &afi[cafn].restart_barrier, NULL) < 0)
 742                 return false;
 743         return true;
 744 }
 745
 746 static void compute_time_diff(const struct timeval *status_time)
 747 {
 748         struct timeval tmp, diff;
 749         static unsigned count;
 750         int sign, sa_time_diff_sign = stat_task->sa_time_diff_sign;
 751         const struct timeval max_deviation = {0, 500 * 1000};
 752         const int time_smooth = 5;
 753
 754         sign = tv_diff(status_time, now, &diff);
 755 //              PARA_NOTICE_LOG("%s: sign = %i, sa_time_diff_sign = %i\n", __func__,
 756 //                      sign, sa_time_diff_sign);
 757         if (!count) {
 758                 sa_time_diff_sign = sign;
 759                 stat_task->sa_time_diff = diff;
 760                 count++;
 761                 goto out;
 762         }
 763         if (count > 5) {
 764                 int s = tv_diff(&diff, &stat_task->sa_time_diff, &tmp);
 765                 if (tv_diff(&max_deviation, &tmp, NULL) < 0)
 766                         PARA_WARNING_LOG("time diff jump: %lims\n",
 767                                 s * tv2ms(&tmp));
 768         }
 769         count++;
 770         sa_time_diff_sign = tv_convex_combination(
 771                 sa_time_diff_sign * time_smooth, &stat_task->sa_time_diff,
 772                 count > 10? sign : sign * time_smooth, &diff,
 773                 &tmp);
 774         stat_task->sa_time_diff = tmp;
 775         PARA_INFO_LOG("time diff (cur/avg): %s%lums/%s%lums\n",
 776                 sign < 0? "-" : "+",
 777                 tv2ms(&diff),
 778                 sa_time_diff_sign < 0? "-" : "+",
 779                 tv2ms(&stat_task->sa_time_diff)
 780         );
 781 out:
 782         stat_task->sa_time_diff_sign = sa_time_diff_sign;
 783 }
 784
 785 static int update_item(int itemnum, char *buf)
 786 {
 787         long unsigned sec, usec;
 788
 789         if (stat_task->clock_diff_count && itemnum != SI_CURRENT_TIME)
 790                 return 1;
 791         free(stat_item_values[itemnum]);
 792         stat_item_values[itemnum] = para_strdup(buf);
 793         stat_client_write_item(itemnum);
 794         switch (itemnum) {
 795         case SI_STATUS_FLAGS:
 796                 stat_task->vss_status = 0;
 797                 if (strchr(buf, 'N'))
 798                         stat_task->vss_status |= VSS_STATUS_FLAG_NEXT;
 799                 if (strchr(buf, 'P'))
 800                         stat_task->vss_status |= VSS_STATUS_FLAG_PLAYING;
 801                 break;
 802         case SI_OFFSET:
 803                 stat_task->offset_seconds = atoi(buf);
 804                 break;
 805         case SI_SECONDS_TOTAL:
 806                 stat_task->length_seconds = atoi(buf);
 807                 break;
 808         case SI_STREAM_START:
 809                 if (sscanf(buf, "%lu.%lu", &sec, &usec) == 2) {
 810                         stat_task->server_stream_start.tv_sec = sec;
 811                         stat_task->server_stream_start.tv_usec = usec;
 812                 }
 813                 break;
 814         case SI_CURRENT_TIME:
 815                 if (sscanf(buf, "%lu.%lu", &sec, &usec) == 2) {
 816                         struct timeval tv = {sec, usec};
 817                         compute_time_diff(&tv);
 818                 }
 819                 break;
 820         case SI_FORMAT:
 821                 stat_task->current_audio_format_num
 822                         = get_audio_format_num(buf);
 823         }
 824         return 1;
 825 }
 826
 827 static int parse_stream_command(const char *txt, char **cmd)
 828 {
 829         int ret, len;
 830         char *re, *p = strchr(txt, ':');
 831
 832         if (!p)
 833                 return -E_MISSING_COLON;
 834         *cmd = p + 1;
 835         len = p - txt;
 836         re = malloc(len + 1);
 837         strncpy(re, txt, len);
 838         re[len] = '\0';
 839         ret = get_matching_audio_format_nums(re);
 840         free(re);
 841         return ret;
 842 }
 843
 844 static int add_filter(int format, char *cmdline)
 845 {
 846         struct audio_format_info *a = &afi[format];
 847         int filter_num, nf = a->num_filters;
 848         void *cfg;
 849
 850         filter_num = check_filter_arg(cmdline, &cfg);
 851         if (filter_num < 0)
 852                 return filter_num;
 853         a->filter_conf = para_realloc(a->filter_conf,
 854                 (nf + 1) * sizeof(void *));
 855         a->filter_nums = para_realloc(a->filter_nums,
 856                 (nf + 1) * sizeof(unsigned));
 857         a->filter_nums[nf] = filter_num;
 858         a->filter_conf[nf] = cfg;
 859         a->num_filters++;
 860         PARA_INFO_LOG("%s filter %d: %s\n", audio_formats[format], nf,
 861                 filters[filter_num].name);
 862         return filter_num;
 863 }
 864
 865 static int parse_writer_args(void)
 866 {
 867         int i, ret;
 868         char *cmd;
 869         struct audio_format_info *a;
 870
 871         for (i = 0; i < conf.writer_given; i++) {
 872                 void *wconf;
 873                 int j, nw, writer_num, af_mask;
 874
 875                 ret = parse_stream_command(conf.writer_arg[i], &cmd);
 876                 if (ret < 0)
 877                         return ret;
 878                 af_mask = ret;
 879                 FOR_EACH_AUDIO_FORMAT(j) {
 880                         a = afi + j;
 881                         if ((af_mask & (1 << j)) == 0) /* no match */
 882                                 continue;
 883                         wconf = check_writer_arg_or_die(cmd, &writer_num);
 884                         nw = a->num_writers;
 885                         a->writer_nums = para_realloc(a->writer_nums, (nw + 1) * sizeof(int));
 886                         a->writer_conf = para_realloc(a->writer_conf, (nw + 1) * sizeof(void *));
 887                         a->writer_nums[nw] = writer_num;
 888                         a->writer_conf[nw] = wconf;
 889                         PARA_INFO_LOG("%s writer #%d: %s\n", audio_formats[j],
 890                                 nw, writer_names[writer_num]);
 891                         a->num_writers++;
 892                 }
 893         }
 894         /* Use default writer for audio formats which are not yet set up. */
 895         FOR_EACH_AUDIO_FORMAT(i) {
 896                 void *writer_conf;
 897                 int writer_num;
 898                 a = afi + i;
 899                 if (a->num_writers > 0)
 900                         continue; /* already set up */
 901                 writer_conf = check_writer_arg_or_die(NULL, &writer_num);
 902                 a->writer_nums = para_malloc(sizeof(int));
 903                 a->writer_nums[0] = writer_num;
 904                 a->writer_conf = para_malloc(sizeof(void *));
 905                 a->writer_conf[0] = writer_conf;
 906                 a->num_writers = 1;
 907                 PARA_INFO_LOG("%s writer: %s (default)\n", audio_formats[i],
 908                         writer_names[writer_num]);
 909         }
 910         return 1;
 911 }
 912
 913 static int parse_receiver_args(void)
 914 {
 915         int i, ret, receiver_num;
 916         char *cmd = NULL;
 917         struct audio_format_info *a;
 918
 919         for (i = conf.receiver_given - 1; i >= 0; i--) {
 920                 char *arg;
 921                 int j, af_mask;
 922
 923                 ret = parse_stream_command(conf.receiver_arg[i], &arg);
 924                 if (ret < 0)
 925                         goto out;
 926                 af_mask = ret;
 927                 FOR_EACH_AUDIO_FORMAT(j) {
 928                         a = afi + j;
 929                         if ((af_mask & (1 << j)) == 0) /* no match */
 930                                 continue;
 931                         /*
 932                          * If multiple receivers are given for this audio format, the
 933                          * last one wins and we have to free the previous receiver
 934                          * config here. Since we are iterating backwards, the winning
 935                          * receiver arg is in fact the first one given.
 936                          */
 937                         if (a->receiver_conf)
 938                                 a->receiver->free_config(a->receiver_conf);
 939                         a->receiver_conf = check_receiver_arg(arg, &receiver_num);
 940                         ret = -E_RECV_SYNTAX;
 941                         if (!a->receiver_conf)
 942                                 goto out;
 943                         a->receiver = receivers + receiver_num;
 944                 }
 945         }
 946         /*
 947          * Use the first available receiver with no arguments for those audio
 948          * formats for which no receiver was specified.
 949          */
 950         cmd = para_strdup(receivers[0].name);
 951         FOR_EACH_AUDIO_FORMAT(i) {
 952                 a = &afi[i];
 953                 if (a->receiver_conf)
 954                         continue;
 955                 a->receiver_conf = check_receiver_arg(cmd, &receiver_num);
 956                 if (!a->receiver_conf)
 957                         return -E_RECV_SYNTAX;
 958                 a->receiver = &receivers[receiver_num];
 959         }
 960         FOR_EACH_AUDIO_FORMAT(i) {
 961                 a = afi + i;
 962                 PARA_INFO_LOG("receiving %s streams via %s receiver\n",
 963                         audio_formats[i], a->receiver->name);
 964         }
 965         ret = 1;
 966 out:
 967         free(cmd);
 968         return ret;
 969 }
 970
 971 static int init_default_filters(void)
 972 {
 973         int i, ret = 1;
 974
 975         FOR_EACH_AUDIO_FORMAT(i) {
 976                 struct audio_format_info *a = &afi[i];
 977                 char *tmp;
 978                 int j;
 979
 980                 if (a->num_filters)
 981                         continue; /* no default -- nothing to to */
 982                 /*
 983                  * udp and dccp streams are fec-encoded, so add fecdec as the
 984                  * first filter.
 985                  */
 986                 if (strcmp(afi[i].receiver->name, "udp") == 0 ||
 987                                 strcmp(afi[i].receiver->name, "dccp") == 0) {
 988                         tmp = para_strdup("fecdec");
 989                         add_filter(i, tmp);
 990                         free(tmp);
 991                         if (ret < 0)
 992                                 goto out;
 993                 }
 994                 /* add "dec" to audio format name */
 995                 tmp = make_message("%sdec", audio_formats[i]);
 996                 for (j = 0; filters[j].name; j++)
 997                         if (!strcmp(tmp, filters[j].name))
 998                                 break;
 999                 free(tmp);
1000                 ret = -E_UNSUPPORTED_FILTER;
1001                 if (!filters[j].name)
1002                         goto out;
1003                 tmp = para_strdup(filters[j].name);
1004                 ret = add_filter(i, tmp);
1005                 free(tmp);
1006                 if (ret < 0)
1007                         goto out;
1008                 PARA_INFO_LOG("%s -> default filter: %s\n", audio_formats[i],
1009                         filters[j].name);
1010         }
1011 out:
1012         return ret;
1013 }
1014
1015 static int parse_filter_args(void)
1016 {
1017         int i, j, ret, af_mask, num_matches;
1018
1019         for (i = 0; i < conf.filter_given; i++) {
1020                 char *arg;
1021                 ret = parse_stream_command(conf.filter_arg[i], &arg);
1022                 if (ret < 0)
1023                         goto out;
1024                 af_mask = ret;
1025                 num_matches = 0;
1026                 FOR_EACH_AUDIO_FORMAT(j) {
1027                         if ((af_mask & (1 << j)) == 0) /* no match */
1028                                 continue;
1029                         ret = add_filter(j, arg);
1030                         if (ret < 0)
1031                                 goto out;
1032                         num_matches++;
1033                 }
1034                 if (num_matches == 0)
1035                         PARA_WARNING_LOG("ignoring filter spec: %s\n",
1036                                 conf.filter_arg[i]);
1037         }
1038         ret = init_default_filters(); /* use default values for the rest */
1039 out:
1040         return ret;
1041 }
1042
1043 static int parse_stream_args(void)
1044 {
1045         int ret;
1046
1047         ret = parse_receiver_args();
1048         if (ret < 0)
1049                 return ret;
1050         ret = parse_filter_args();
1051         if (ret < 0)
1052                 return ret;
1053         ret = parse_writer_args();
1054         if (ret < 0)
1055                 return ret;
1056         return 1;
1057 }
1058
1059 /* does not unlink socket on errors */
1060 static void init_local_sockets(struct command_task *ct)
1061 {
1062         if (conf.socket_given)
1063                 socket_name = para_strdup(conf.socket_arg);
1064         else {
1065                 char *hn = para_hostname();
1066                 socket_name = make_message("/var/paraslash/audiod_socket.%s",
1067                         hn);
1068                 free(hn);
1069         }
1070         PARA_NOTICE_LOG("local socket: %s\n", socket_name);
1071         if (conf.force_given)
1072                 unlink(socket_name);
1073         ct->fd[0] = create_local_socket(socket_name, 0);
1074         ct->fd[1] = create_local_socket(socket_name,
1075                 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IWOTH);
1076         if (ct->fd[0] >= 0 || ct->fd[1] >= 0)
1077                 return;
1078         PARA_EMERG_LOG("%s\n", para_strerror(-ct->fd[1]));
1079         exit(EXIT_FAILURE);
1080 }
1081
1082 static int signal_post_select(struct sched *s, void *context)
1083 {
1084         struct signal_task *st = context;
1085         int ret, signum;
1086
1087         ret = task_get_notification(st->task);
1088         if (ret < 0)
1089                 return ret;
1090         signum = para_next_signal(&s->rfds);
1091         switch (signum) {
1092         case SIGINT:
1093         case SIGTERM:
1094         case SIGHUP:
1095                 PARA_NOTICE_LOG("received signal %d\n", signum);
1096                 task_notify_all(s, E_AUDIOD_SIGNAL);
1097                 return -E_AUDIOD_SIGNAL;
1098         }
1099         return 0;
1100 }
1101
1102 static void command_pre_select(struct sched *s, void *context)
1103 {
1104         struct command_task *ct = context;
1105         int i;
1106
1107         for (i = 0; i < 2; i++)
1108                 if (ct->fd[i] >= 0)
1109                         para_fd_set(ct->fd[i], &s->rfds, &s->max_fileno);
1110 }
1111
1112 static int command_post_select(struct sched *s, void *context)
1113 {
1114         int ret, i;
1115         struct command_task *ct = context;
1116         static struct timeval last_status_dump;
1117         struct timeval tmp, delay;
1118         bool force = false;
1119
1120         ret = task_get_notification(ct->task);
1121         if (ret < 0)
1122                 return ret;
1123         for (i = 0; i < 2; i++) {
1124                 if (ct->fd[i] < 0)
1125                         continue;
1126                 ret = handle_connect(ct->fd[i], &s->rfds, uid_whitelist);
1127                 if (ret < 0) {
1128                         PARA_ERROR_LOG("%s\n", para_strerror(-ret));
1129                         if (ret == -E_AUDIOD_TERM) {
1130                                 task_notify_all(s, -ret);
1131                                 return ret;
1132                         }
1133                 } else if (ret > 0)
1134                         force = true;
1135         }
1136         if (force == true)
1137                 goto dump;
1138
1139         /* if last status dump was less than 500ms ago, do nothing */
1140         delay.tv_sec = 0;
1141         delay.tv_usec = 500 * 1000;
1142         tv_add(&last_status_dump, &delay, &tmp);
1143         if (tv_diff(now, &tmp, NULL) < 0)
1144                 return 0;
1145
1146         /*
1147          * If last status dump was more than 5s ago, force update. Otherwise,
1148          * update only those items that have changed.
1149          */
1150         delay.tv_sec = 5;
1151         delay.tv_usec = 0;
1152         tv_add(&last_status_dump, &delay, &tmp);
1153         if (tv_diff(now, &tmp, NULL) > 0)
1154                 force = true;
1155 dump:
1156         audiod_status_dump(force);
1157         last_status_dump = *now;
1158         return 1;
1159 }
1160
1161 static void init_command_task(struct command_task *ct)
1162 {
1163         init_local_sockets(ct); /* doesn't return on errors */
1164
1165         ct->task = task_register(&(struct task_info) {
1166                 .name = "command",
1167                 .pre_select = command_pre_select,
1168                 .post_select = command_post_select,
1169                 .context = ct,
1170         }, &sched);
1171 }
1172
1173 static void close_stat_pipe(void)
1174 {
1175         if (!stat_task->ct)
1176                 return;
1177         task_reap(&stat_task->ct->task);
1178         client_close(stat_task->ct);
1179         stat_task->ct = NULL;
1180         clear_and_dump_items();
1181         stat_task->length_seconds = 0;
1182         stat_task->offset_seconds = 0;
1183         stat_task->vss_status = 0;
1184         stat_task->current_audio_format_num = -1;
1185         audiod_status_dump(true);
1186 }
1187
1188 /* avoid busy loop if server is down */
1189 static void set_stat_task_restart_barrier(unsigned seconds)
1190 {
1191         struct timeval delay = {seconds, 0};
1192         tv_add(now, &delay, &stat_task->restart_barrier);
1193 }
1194
1195 static bool must_close_slot(int slot_num)
1196 {
1197         struct slot_info *s = &slot[slot_num];
1198         struct audio_format_info *a = afi + s->format;
1199         int i;
1200
1201         if (s->format < 0)
1202                 return false;
1203         if (s->receiver_node && task_status(s->receiver_node->task) >= 0)
1204                 return false;
1205         for (i = 0; i < a->num_filters; i++)
1206                 if (s->fns && task_status(s->fns[i].task) >= 0)
1207                         return false;
1208         if (a->num_writers > 0) {
1209                 for (i = 0; i < a->num_writers; i++)
1210                         if (s->wns && task_status(s->wns[i].task) >= 0)
1211                                 return false;
1212         } else {
1213                 if (s->wns && task_status(s->wns[0].task) >= 0)
1214                         return false;
1215         }
1216         return true;
1217 }
1218
1219 static void close_slot(int slot_num)
1220 {
1221         struct slot_info *s = slot + slot_num;
1222
1223         PARA_INFO_LOG("closing slot %d\n", slot_num);
1224         close_writers(s);
1225         close_filters(s);
1226         close_receiver(slot_num);
1227         clear_slot(slot_num);
1228 }
1229
1230 static void close_unused_slots(void)
1231 {
1232         int i;
1233
1234         FOR_EACH_SLOT(i)
1235                 if (must_close_slot(i))
1236                         close_slot(i);
1237 }
1238
1239 /*
1240  * Cleanup all resources.
1241  *
1242  * This performs various cleanups, removes the audiod socket and closes the
1243  * connection to para_server.
1244  */
1245 static void audiod_cleanup(void)
1246 {
1247         if (socket_name)
1248                 unlink(socket_name);
1249         close_stat_pipe();
1250         close_unused_slots();
1251         audiod_cmdline_parser_free(&conf);
1252         close_stat_clients();
1253         free(uid_whitelist);
1254 }
1255
1256 /*
1257  * Check if any receivers/filters/writers need to be started and do so if
1258  * necessary.
1259  */
1260 static void start_stop_decoders(void)
1261 {
1262         int ret;
1263         struct slot_info *sl;
1264
1265         close_unused_slots();
1266         if (audiod_status != AUDIOD_ON ||
1267                         !(stat_task->vss_status & VSS_STATUS_FLAG_PLAYING))
1268                 return notify_receivers(E_NOT_PLAYING);
1269         if (!must_start_decoder())
1270                 return;
1271         ret = open_receiver(stat_task->current_audio_format_num);
1272         if (ret < 0) {
1273                 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
1274                 return;
1275         }
1276         sl = slot + ret;
1277         open_filters(sl);
1278         open_writers(sl);
1279         activate_grab_clients(&sched);
1280         btr_log_tree(sl->receiver_node->btrn, LL_NOTICE);
1281 }
1282
1283 static void status_pre_select(struct sched *s, void *context)
1284 {
1285         struct status_task *st = context;
1286         int i, ret, cafn = stat_task->current_audio_format_num;
1287
1288         if (must_start_decoder())
1289                 goto min_delay;
1290         FOR_EACH_SLOT(i)
1291                 if (must_close_slot(i))
1292                         goto min_delay;
1293         ret = btr_node_status(st->btrn, st->min_iqs, BTR_NT_LEAF);
1294         if (ret > 0)
1295                 goto min_delay;
1296         if (st->ct && audiod_status == AUDIOD_OFF)
1297                 goto min_delay;
1298         if (!st->ct && audiod_status != AUDIOD_OFF)
1299                 sched_request_barrier_or_min_delay(&st->restart_barrier, s);
1300         if (cafn >= 0)
1301                 sched_request_barrier(&afi[cafn].restart_barrier, s);
1302         /*
1303          * If para_server is playing we'd like to have a smooth time display
1304          * even if we are running in standby mode. So we request a timeout that
1305          * expires at the next full second.
1306          */
1307         if (stat_task->vss_status & VSS_STATUS_FLAG_PLAYING)
1308                 sched_request_timeout_ms(1000 - now->tv_usec / 1000, s);
1309         return;
1310 min_delay:
1311         sched_min_delay(s);
1312 }
1313
1314 /* restart the client task if necessary */
1315 static int status_post_select(struct sched *s, void *context)
1316 {
1317         struct status_task *st = context;
1318         int ret;
1319
1320         ret = task_get_notification(st->task);
1321         if (ret < 0)
1322                 return ret;
1323         if (audiod_status == AUDIOD_OFF) {
1324                 if (!st->ct)
1325                         goto out;
1326                 if (task_status(st->ct->task) >= 0) {
1327                         task_notify(st->ct->task, E_AUDIOD_OFF);
1328                         goto out;
1329                 }
1330                 close_stat_pipe();
1331                 st->clock_diff_count = conf.clock_diff_count_arg;
1332                 goto out;
1333         }
1334         if (st->ct) {
1335                 char *buf;
1336                 size_t sz;
1337
1338                 ret = btr_node_status(st->btrn, st->min_iqs, BTR_NT_LEAF);
1339                 if (ret < 0) {
1340                         close_stat_pipe();
1341                         goto out;
1342                 }
1343                 if (st->ct->status != CL_EXECUTING)
1344                         goto out;
1345                 if (ret == 0) {
1346                         struct timeval diff;
1347                         tv_diff(now, &st->last_status_read, &diff);
1348                         if (diff.tv_sec > 61)
1349                                 task_notify(st->ct->task, E_STATUS_TIMEOUT);
1350                         goto out;
1351                 }
1352                 btr_merge(st->btrn, st->min_iqs);
1353                 sz = btr_next_buffer(st->btrn, &buf);
1354                 ret = for_each_stat_item(buf, sz, update_item);
1355                 if (ret < 0) {
1356                         task_notify(st->ct->task, -ret);
1357                         goto out;
1358                 }
1359                 if (sz != ret) {
1360                         btr_consume(st->btrn, sz - ret);
1361                         st->last_status_read = *now;
1362                         st->min_iqs = 0;
1363                 } else /* current status item crosses buffers */
1364                         st->min_iqs = sz + 1;
1365                 goto out;
1366         }
1367         btr_drain(st->btrn);
1368         st->current_audio_format_num = -1;
1369         if (tv_diff(now, &st->restart_barrier, NULL) < 0)
1370                 goto out;
1371         if (st->clock_diff_count) { /* get status only one time */
1372                 char *argv[] = {"audiod", "--", "stat", "-p", "-n=1", NULL};
1373                 int argc = 5;
1374                 PARA_INFO_LOG("clock diff count: %d\n", st->clock_diff_count);
1375                 st->clock_diff_count--;
1376                 client_open(argc, argv, &st->ct, NULL, NULL, st->btrn, s);
1377                 set_stat_task_restart_barrier(2);
1378
1379         } else {
1380                 char *argv[] = {"audiod", "--", "stat", "-p", NULL};
1381                 int argc = 4;
1382                 client_open(argc, argv, &st->ct, NULL, NULL, st->btrn, s);
1383                 set_stat_task_restart_barrier(5);
1384         }
1385         free(stat_item_values[SI_BASENAME]);
1386         stat_item_values[SI_BASENAME] = para_strdup(
1387                 "no connection to para_server");
1388         stat_client_write_item(SI_BASENAME);
1389         st->last_status_read = *now;
1390 out:
1391         start_stop_decoders();
1392         return 0;
1393 }
1394
1395 static void init_status_task(struct status_task *st)
1396 {
1397         memset(st, 0, sizeof(struct status_task));
1398         st->sa_time_diff_sign = 1;
1399         st->clock_diff_count = conf.clock_diff_count_arg;
1400         st->current_audio_format_num = -1;
1401         st->btrn = btr_new_node(&(struct btr_node_description)
1402                 EMBRACE(.name = "stat"));
1403
1404         stat_task->task = task_register(&(struct task_info) {
1405                 .name = "stat",
1406                 .pre_select = status_pre_select,
1407                 .post_select = status_post_select,
1408                 .context = stat_task,
1409         }, &sched);
1410 }
1411
1412 static void set_initial_status(void)
1413 {
1414         audiod_status = AUDIOD_ON;
1415         if (!conf.mode_given)
1416                 return;
1417         if (!strcmp(conf.mode_arg, "sb")) {
1418                 audiod_status = AUDIOD_STANDBY;
1419                 return;
1420         }
1421         if (!strcmp(conf.mode_arg, "off")) {
1422                 audiod_status = AUDIOD_OFF;
1423                 return;
1424         }
1425         if (strcmp(conf.mode_arg, "on"))
1426                 PARA_WARNING_LOG("invalid mode\n");
1427 }
1428
1429 __noreturn static void print_help_and_die(void)
1430 {
1431         struct ggo_help h = DEFINE_GGO_HELP(audiod);
1432         bool d = conf.detailed_help_given;
1433         unsigned flags;
1434
1435         flags = d? GPH_STANDARD_FLAGS_DETAILED : GPH_STANDARD_FLAGS;
1436         ggo_print_help(&h, flags);
1437
1438         flags = d? GPH_MODULE_FLAGS_DETAILED : GPH_MODULE_FLAGS;
1439         print_receiver_helps(flags);
1440         print_filter_helps(flags);
1441         print_writer_helps(flags);
1442         exit(0);
1443 }
1444
1445 /**
1446  * the main function of para_audiod
1447  *
1448  * \param argc usual argument count
1449  * \param argv usual argument vector
1450  *
1451  * \return EXIT_SUCCESS or EXIT_FAILURE
1452  *
1453  * \sa para_audiod(1)
1454  * */
1455 int main(int argc, char *argv[])
1456 {
1457         int ret, i;
1458         struct command_task command_task_struct, *cmd_task = &command_task_struct;
1459         struct audiod_cmdline_parser_params params = {
1460                 .override = 0,
1461                 .initialize = 1,
1462                 .check_required = 0,
1463                 .check_ambiguity = 0,
1464                 .print_errors = 1
1465         };
1466
1467         valid_fd_012();
1468         audiod_cmdline_parser_ext(argc, argv, &conf, &params);
1469         daemon_set_loglevel(conf.loglevel_arg);
1470         version_handle_flag("audiod", conf.version_given);
1471         /* init receivers/filters/writers early to make help work */
1472         recv_init();
1473         filter_init();
1474         writer_init();
1475         if (conf.help_given || conf.detailed_help_given)
1476                 print_help_and_die();
1477         daemon_drop_privileges_or_die(conf.user_arg, conf.group_arg);
1478         parse_config_or_die();
1479         daemon_init_colors_or_die(conf.color_arg, color_arg_auto, color_arg_no,
1480                 conf.logfile_given, conf.log_color_arg, conf.log_color_given);
1481         init_random_seed_or_die();
1482         daemon_set_flag(DF_LOG_TIME);
1483         daemon_set_flag(DF_LOG_HOSTNAME);
1484         daemon_set_flag(DF_LOG_LL);
1485         if (conf.log_timing_given)
1486                 daemon_set_flag(DF_LOG_TIMING);
1487         if (conf.logfile_given) {
1488                 daemon_set_logfile(conf.logfile_arg);
1489                 daemon_open_log_or_die();
1490         }
1491         ret = parse_stream_args();
1492         if (ret < 0) {
1493                 PARA_EMERG_LOG("%s\n", para_strerror(-ret));
1494                 exit(EXIT_FAILURE);
1495         }
1496         daemon_log_welcome("audiod");
1497         daemon_set_start_time();
1498         set_initial_status();
1499         FOR_EACH_SLOT(i)
1500                 clear_slot(i);
1501         setup_signal_handling();
1502
1503         init_status_task(stat_task);
1504         init_command_task(cmd_task);
1505
1506         if (conf.daemon_given)
1507                 daemonize(false /* parent exits immediately */);
1508
1509         signal_task->task = task_register(&(struct task_info) {
1510                 .name = "signal",
1511                 .pre_select = signal_pre_select,
1512                 .post_select = signal_post_select,
1513                 .context = signal_task,
1514         }, &sched);
1515
1516         sched.default_timeout.tv_sec = 2;
1517         sched.default_timeout.tv_usec = 999 * 1000;
1518         ret = schedule(&sched);
1519         audiod_cleanup();
1520         sched_shutdown(&sched);
1521         signal_shutdown(signal_task);
1522
1523         if (ret < 0)
1524                 PARA_EMERG_LOG("%s\n", para_strerror(-ret));
1525         return ret < 0? EXIT_FAILURE : EXIT_SUCCESS;
1526 }