vss.c

   1 /*
   2  * Copyright (C) 1997-2008 Andre Noll <maan@systemlinux.org>
   3  *
   4  * Licensed under the GPL v2. For licencing details see COPYING.
   5  */
   6
   7 /** \file vss.c The virtual streaming system.
   8  *
   9  * This contains the audio streaming code of para_server which is independent
  10  * of the current audio format, audio file selector and of the activated
  11  * senders.
  12  */
  13
  14 #include <sys/mman.h> /* mmap */
  15 #include <sys/time.h> /* gettimeofday */
  16 #include <sys/types.h>
  17 #include <dirent.h>
  18
  19 #include "para.h"
  20 #include "error.h"
  21 #include "string.h"
  22 #include "afh.h"
  23 #include "afs.h"
  24 #include "server.h"
  25 #include "net.h"
  26 #include "server.cmdline.h"
  27 #include "vss.h"
  28 #include "list.h"
  29 #include "send.h"
  30 #include "ipc.h"
  31 #include "fd.h"
  32
  33 static struct timeval announce_tv;
  34 static struct timeval data_send_barrier;
  35 static struct timeval eof_barrier;
  36 static struct timeval autoplay_barrier;
  37
  38 extern struct misc_meta_data *mmd;
  39
  40 extern void dccp_send_init(struct sender *);
  41 extern void http_send_init(struct sender *);
  42 extern void ortp_send_init(struct sender *);
  43
  44 /** the list of supported senders */
  45 struct sender senders[] = {
  46         {
  47                 .name = "http",
  48                 .init = http_send_init,
  49         },
  50         {
  51                 .name = "dccp",
  52                 .init = dccp_send_init,
  53         },
  54 #ifdef HAVE_ORTP
  55         {
  56                 .name = "ortp",
  57                 .init = ortp_send_init,
  58         },
  59 #endif
  60         {
  61                 .name = NULL,
  62         }
  63 };
  64
  65
  66
  67 static char *map;
  68
  69 /**
  70  * Check if vss status flag \a P (playing) is set.
  71  *
  72  * \return Greater than zero if playing, zero otherwise.
  73  *
  74  */
  75 unsigned int vss_playing(void)
  76 {
  77         return mmd->new_vss_status_flags & VSS_PLAYING;
  78 }
  79
  80 /**
  81  * Check if the \a N (next) status flag is set.
  82  *
  83  * \return Greater than zero if set, zero if not.
  84  *
  85  */
  86 unsigned int vss_next(void)
  87 {
  88         return mmd->new_vss_status_flags & VSS_NEXT;
  89 }
  90
  91 /**
  92  * Check if a reposition request is pending.
  93  *
  94  * \return Greater than zero if true, zero otherwise.
  95  *
  96  */
  97 unsigned int vss_repos(void)
  98 {
  99         return mmd->new_vss_status_flags & VSS_REPOS;
 100 }
 101
 102 /**
 103  * Check if the vss is currently paused.
 104  *
 105  * \return Greater than zero if paused, zero otherwise.
 106  *
 107  */
 108 unsigned int vss_paused(void)
 109 {
 110         return !(mmd->new_vss_status_flags & VSS_NEXT)
 111                 && !(mmd->new_vss_status_flags & VSS_PLAYING);
 112 }
 113
 114 /**
 115  * Check if the vss is currently stopped.
 116  *
 117  * \return Greater than zero if paused, zero otherwise.
 118  *
 119  */
 120 unsigned int vss_stopped(void)
 121 {
 122         return (mmd->new_vss_status_flags & VSS_NEXT)
 123                 && !(mmd->new_vss_status_flags & VSS_PLAYING);
 124 }
 125
 126 /**
 127  * Get the data of the given chunk.
 128  *
 129  * \param chunk_num The number of the desired chunk.
 130  * \param buf Chunk data.
 131  * \param len Chunk length in bytes.
 132  *
 133  * \return Standard.
 134  */
 135 int vss_get_chunk(long unsigned chunk_num, char **buf, size_t *len)
 136 {
 137         if (!map || !vss_playing())
 138                 return -E_CHUNK;
 139         if (chunk_num >= mmd->afd.afhi.chunks_total)
 140                 return -E_CHUNK;
 141         afh_get_chunk(chunk_num, &mmd->afd.afhi, map, buf, len);
 142         return 1;
 143 }
 144
 145 /**
 146  * Initialize the virtual streaming system.
 147  *
 148  * This also initializes all supported senders and starts streaming
 149  * if the --autoplay command line flag was given.
 150  */
 151 void vss_init(void)
 152 {
 153         int i;
 154         char *hn = para_hostname(), *home = para_homedir();
 155         long unsigned announce_time = conf.announce_time_arg > 0?
 156                         conf.announce_time_arg : 300,
 157                 autoplay_delay = conf.autoplay_delay_arg > 0?
 158                         conf.autoplay_delay_arg : 0;
 159         ms2tv(announce_time, &announce_tv);
 160         PARA_INFO_LOG("announce timeval: %lums\n", tv2ms(&announce_tv));
 161         for (i = 0; senders[i].name; i++) {
 162                 PARA_NOTICE_LOG("initializing %s sender\n", senders[i].name);
 163                 senders[i].init(&senders[i]);
 164         }
 165         free(hn);
 166         free(home);
 167         mmd->sender_cmd_data.cmd_num = -1;
 168         if (conf.autoplay_given) {
 169                 struct timeval now, tmp;
 170                 mmd->vss_status_flags |= VSS_PLAYING;
 171                 mmd->new_vss_status_flags |= VSS_PLAYING;
 172                 gettimeofday(&now, NULL);
 173                 ms2tv(autoplay_delay, &tmp);
 174                 tv_add(&now, &tmp, &autoplay_barrier);
 175         }
 176 }
 177
 178 static int chk_barrier(const char *bname, const struct timeval *now,
 179                 const struct timeval *barrier, struct timeval *diff,
 180                 int print_log)
 181 {
 182         long ms;
 183
 184         if (tv_diff(now, barrier, diff) > 0)
 185                 return 1;
 186         ms = tv2ms(diff);
 187         if (print_log && ms)
 188                 PARA_DEBUG_LOG("%s barrier: %lims left\n", bname, ms);
 189         return -1;
 190 }
 191
 192 /*
 193  * != NULL: timeout for next chunk
 194  * NULL: nothing to do
 195  */
 196 static struct timeval *vss_compute_timeout(void)
 197 {
 198         static struct timeval the_timeout;
 199         struct timeval now, next_chunk;
 200
 201         if (vss_next() && map) {
 202                 /* only sleep a bit, nec*/
 203                 the_timeout.tv_sec = 0;
 204                 the_timeout.tv_usec = 100;
 205                 return &the_timeout;
 206         }
 207         gettimeofday(&now, NULL);
 208         if (chk_barrier("autoplay_delay", &now, &autoplay_barrier,
 209                         &the_timeout, 1) < 0)
 210                 return &the_timeout;
 211         if (chk_barrier("eof", &now, &eof_barrier, &the_timeout, 1) < 0)
 212                 return &the_timeout;
 213         if (chk_barrier("data send", &now, &data_send_barrier,
 214                         &the_timeout, 1) < 0)
 215                 return &the_timeout;
 216         if (!vss_playing() || !map)
 217                 return NULL;
 218         compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
 219                 &mmd->stream_start, &next_chunk);
 220         if (chk_barrier("chunk", &now, &next_chunk, &the_timeout, 0) < 0)
 221                 return &the_timeout;
 222         /* chunk is due or bof */
 223         the_timeout.tv_sec = 0;
 224         the_timeout.tv_usec = 0;
 225         return &the_timeout;
 226 }
 227
 228 static void vss_eof(void)
 229 {
 230         struct timeval now;
 231         char *tmp;
 232
 233         if (!map)
 234                 return;
 235         if (mmd->new_vss_status_flags & VSS_NOMORE)
 236                 mmd->new_vss_status_flags = VSS_NEXT;
 237         gettimeofday(&now, NULL);
 238         tv_add(&mmd->afd.afhi.eof_tv, &now, &eof_barrier);
 239         para_munmap(map, mmd->size);
 240         map = NULL;
 241         mmd->chunks_sent = 0;
 242         mmd->offset = 0;
 243         mmd->afd.afhi.seconds_total = 0;
 244         free(mmd->afd.afhi.chunk_table);
 245         mmd->afd.afhi.chunk_table = NULL;
 246         tmp  = make_message("%s:\n%s:\n%s:\n", status_item_list[SI_AUDIO_FILE_INFO],
 247                 status_item_list[SI_TAGINFO1], status_item_list[SI_TAGINFO2]);
 248         strncpy(mmd->afd.afhi.info_string, tmp, sizeof(mmd->afd.afhi.info_string));
 249         mmd->afd.afhi.info_string[sizeof(mmd->afd.afhi.info_string) - 1] = '\0';
 250         make_empty_status_items(mmd->afd.verbose_ls_output);
 251         free(tmp);
 252         mmd->mtime = 0;
 253         mmd->size = 0;
 254         mmd->events++;
 255 }
 256
 257 /**
 258  * Get the header of the current audio file.
 259  *
 260  * \param buf The length of the header is stored here.
 261  * \param len Points to a buffer containing the header on return.
 262  *
 263  * \sa afh_get_header.
 264  */
 265 void vss_get_header(char **buf, size_t *len)
 266 {
 267         afh_get_header(&mmd->afd.afhi, map, buf, len);
 268 }
 269
 270 /**
 271  * Get the list of all supported audio formats.
 272  *
 273  * \return Aa space separated list of all supported audio formats
 274  * It is not allocated at runtime, i.e. there is no need to free
 275  * the returned string in the caller.
 276  */
 277 const char *supported_audio_formats(void)
 278 {
 279         return SUPPORTED_AUDIO_FORMATS;
 280 }
 281
 282 /**
 283  * Get the chunk time of the current audio file.
 284  *
 285  * \return A pointer to a struct containing the chunk time, or NULL,
 286  * if currently no audio file is selected.
 287  */
 288 struct timeval *vss_chunk_time(void)
 289 {
 290         if (!map)
 291                 return NULL;
 292         return &mmd->afd.afhi.chunk_tv;
 293 }
 294
 295 /** The possible states of the afs socket. See \ref afs_socket. */
 296 enum afs_socket_status {
 297         /** Socket is inactive. */
 298         AFS_SOCKET_READY,
 299         /** Socket fd was included in the write fd set for select(). */
 300         AFS_SOCKET_CHECK_FOR_WRITE,
 301         /** vss wrote a request to the socket and waits for afs to reply. */
 302         AFS_SOCKET_AFD_PENDING
 303 };
 304
 305 static enum afs_socket_status afsss;
 306
 307 static int need_to_request_new_audio_file(void)
 308 {
 309         if (map) /* have audio file */
 310                 return 0;
 311         if (!vss_playing()) /* don't need one */
 312                 return 0;
 313         if (mmd->new_vss_status_flags & VSS_NOMORE)
 314                 return 0;
 315         if (afsss == AFS_SOCKET_AFD_PENDING) /* already requested one */
 316                 return 0;
 317         return 1;
 318 }
 319
 320 /**
 321  * Compute the timeout for para_server's main select-loop.
 322  *
 323  * This function gets called from para_server to determine the timeout value
 324  * for its main select loop.
 325  *
 326  * \param rfds The set of file descriptors to be checked for reading.
 327  * \param wfds The set of file descriptors to be checked for writing.
 328  * \param max_fileno The highest-numbered file descriptor.
 329  *
 330  * Before the timeout is computed, the current vss status flags are evaluated
 331  * and acted upon by calling appropriate functions from the lower layers.
 332  * Possible actions include
 333  *
 334  *      - request a new audio file from afs,
 335  *      - shutdown of all senders (stop/pause command),
 336  *      - reposition the stream (ff/jmp command).
 337  *
 338  * \return A pointer to a struct timeval containing the timeout for the next
 339  * chunk of data to be sent, or NULL if we're not sending right now.
 340  */
 341 struct timeval *vss_preselect(fd_set *rfds, fd_set *wfds, int *max_fileno)
 342 {
 343         int i;
 344         struct timeval now;
 345
 346         if (!map || vss_next() || vss_paused() || vss_repos())
 347                 for (i = 0; senders[i].name; i++)
 348                         senders[i].shutdown_clients();
 349         if (vss_next())
 350                 vss_eof();
 351         else if (vss_paused()) {
 352                 if (mmd->chunks_sent) {
 353                         gettimeofday(&now, NULL);
 354                         tv_add(&mmd->afd.afhi.eof_tv, &now, &eof_barrier);
 355                 }
 356                 mmd->chunks_sent = 0;
 357         } else if (vss_repos()) {
 358                 gettimeofday(&now, NULL);
 359                 tv_add(&now, &announce_tv, &data_send_barrier);
 360                 tv_add(&mmd->afd.afhi.eof_tv, &now, &eof_barrier);
 361                 mmd->chunks_sent = 0;
 362                 mmd->current_chunk = mmd->repos_request;
 363                 mmd->new_vss_status_flags &= ~VSS_REPOS;
 364         }
 365
 366         if (need_to_request_new_audio_file()) {
 367                 PARA_DEBUG_LOG("ready and playing, but no audio file\n");
 368                 para_fd_set(afs_socket, wfds, max_fileno);
 369                 afsss = AFS_SOCKET_CHECK_FOR_WRITE;
 370         } else
 371                 para_fd_set(afs_socket, rfds, max_fileno);
 372         for (i = 0; senders[i].name; i++) {
 373                 if (!senders[i].pre_select)
 374                         continue;
 375                 senders[i].pre_select(max_fileno, rfds, wfds);
 376         }
 377         return vss_compute_timeout();
 378 }
 379
 380 static int recv_afs_msg(int *fd, uint32_t *code, uint32_t *data)
 381 {
 382         char control[255], buf[8];
 383         struct msghdr msg = {.msg_iov = NULL};
 384         struct cmsghdr *cmsg;
 385         struct iovec iov;
 386         int ret = 0;
 387
 388         *fd = -1;
 389         iov.iov_base = buf;
 390         iov.iov_len = sizeof(buf);
 391         msg.msg_iov = &iov;
 392         msg.msg_iovlen = 1;
 393         msg.msg_control = control;
 394         msg.msg_controllen = sizeof(control);
 395         memset(buf, 0, sizeof(buf));
 396         ret = recvmsg(afs_socket, &msg, 0);
 397         if (ret < 0)
 398                 return -ERRNO_TO_PARA_ERROR(errno);
 399         afsss = AFS_SOCKET_READY;
 400         if (iov.iov_len != sizeof(buf))
 401                 return -E_AFS_SHORT_READ;
 402         *code = *(uint32_t*)buf;
 403         *data =  *(uint32_t*)(buf + 4);
 404         for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
 405                 if (cmsg->cmsg_level != SOL_SOCKET
 406                         || cmsg->cmsg_type != SCM_RIGHTS)
 407                 continue;
 408                 if ((cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int) != 1)
 409                 continue;
 410                 *fd = *(int *)CMSG_DATA(cmsg);
 411         }
 412         return 1;
 413 }
 414
 415 static void recv_afs_result(void)
 416 {
 417         int ret, passed_fd, shmid;
 418         uint32_t afs_code = 0, afs_data = 0;
 419         struct stat statbuf;
 420         struct timeval now;
 421
 422         mmd->afd.afhi.chunk_table = NULL;
 423         ret = recv_afs_msg(&passed_fd, &afs_code, &afs_data);
 424         if (ret < 0)
 425                 goto err;
 426         PARA_DEBUG_LOG("fd: %d, code: %u, shmid: %u\n", passed_fd, afs_code,
 427                 afs_data);
 428         ret = -E_NOFD;
 429         if (afs_code != NEXT_AUDIO_FILE)
 430                 goto err;
 431         if (passed_fd < 0)
 432                 goto err;
 433         shmid = afs_data;
 434         ret = load_afd(shmid, &mmd->afd);
 435         if (ret < 0)
 436                 goto err;
 437         shm_destroy(shmid);
 438         ret = fstat(passed_fd, &statbuf);
 439         if (ret < 0) {
 440                 PARA_ERROR_LOG("fstat error:\n");
 441                 ret = -ERRNO_TO_PARA_ERROR(errno);
 442                 goto err;
 443         }
 444         mmd->size = statbuf.st_size;
 445         mmd->mtime = statbuf.st_mtime;
 446         map = para_mmap(mmd->size, PROT_READ, MAP_PRIVATE,
 447                 passed_fd, 0);
 448         close(passed_fd);
 449         mmd->chunks_sent = 0;
 450         mmd->current_chunk = 0;
 451         mmd->offset = 0;
 452         mmd->events++;
 453         mmd->num_played++;
 454         mmd->new_vss_status_flags &= (~VSS_NEXT);
 455         gettimeofday(&now, NULL);
 456         tv_add(&now, &announce_tv, &data_send_barrier);
 457         return;
 458 err:
 459         free(mmd->afd.afhi.chunk_table);
 460         if (passed_fd >= 0)
 461                 close(passed_fd);
 462         PARA_ERROR_LOG("%s\n", para_strerror(-ret));
 463         mmd->new_vss_status_flags = VSS_NEXT;
 464 }
 465
 466 /**
 467  * Main sending function.
 468  *
 469  * This function gets called from para_server as soon as the next chunk of data
 470  * should be pushed out. It obtains a pointer to the data to be sent out as
 471  * well as its length from mmd->afd.afhi. This information is then passed to
 472  * each supported sender's send() function which is supposed to send out the data
 473  * to all connected clients.
 474  */
 475 static void vss_send_chunk(void)
 476 {
 477         int i;
 478         struct timeval now, due;
 479         char *buf;
 480         size_t len;
 481
 482         if (!map || !vss_playing())
 483                 return;
 484         gettimeofday(&now, NULL);
 485         compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
 486                 &mmd->stream_start, &due);
 487         if (tv_diff(&due, &now, NULL) > 0)
 488                 return;
 489         if (chk_barrier("eof", &now, &eof_barrier, &due, 1) < 0)
 490                 return;
 491         if (chk_barrier("data send", &now, &data_send_barrier,
 492                         &due, 1) < 0)
 493                 return;
 494         mmd->new_vss_status_flags &= ~VSS_REPOS;
 495         if (mmd->current_chunk >= mmd->afd.afhi.chunks_total) { /* eof */
 496                 mmd->new_vss_status_flags |= VSS_NEXT;
 497                 return;
 498         }
 499         /*
 500          * We call the send function also in case of empty chunks as they
 501          * might have still some data queued which can be sent in this case.
 502          */
 503         if (!mmd->chunks_sent) {
 504                 struct timeval tmp;
 505                 gettimeofday(&mmd->stream_start, NULL);
 506                 tv_scale(mmd->current_chunk, &mmd->afd.afhi.chunk_tv, &tmp);
 507                 mmd->offset = tv2ms(&tmp);
 508                 mmd->events++;
 509         }
 510         afh_get_chunk(mmd->current_chunk, &mmd->afd.afhi, map, &buf, &len);
 511         for (i = 0; senders[i].name; i++)
 512                 senders[i].send(mmd->current_chunk, mmd->chunks_sent, buf, len);
 513         mmd->new_vss_status_flags |= VSS_PLAYING;
 514         mmd->chunks_sent++;
 515         mmd->current_chunk++;
 516 }
 517
 518 void vss_post_select(fd_set *rfds, fd_set *wfds)
 519 {
 520         int ret, i;
 521
 522         if (mmd->sender_cmd_data.cmd_num >= 0) {
 523                 int num = mmd->sender_cmd_data.cmd_num,
 524                         s = mmd->sender_cmd_data.sender_num;
 525
 526                 if (senders[s].client_cmds[num])
 527                         senders[s].client_cmds[num](&mmd->sender_cmd_data);
 528                 mmd->sender_cmd_data.cmd_num = -1;
 529         }
 530         if (afsss != AFS_SOCKET_CHECK_FOR_WRITE) {
 531                 if (FD_ISSET(afs_socket, rfds))
 532                         recv_afs_result();
 533         } else if (FD_ISSET(afs_socket, wfds)) {
 534                 PARA_NOTICE_LOG("requesting new fd from afs\n");
 535                 ret = send_buffer(afs_socket, "new");
 536                 afsss = AFS_SOCKET_AFD_PENDING;
 537         }
 538         for (i = 0; senders[i].name; i++) {
 539                 if (!senders[i].post_select)
 540                         continue;
 541                 senders[i].post_select(rfds, wfds);
 542         }
 543         vss_send_chunk();
 544 }