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 extern struct misc_meta_data *mmd;
  34
  35 extern void dccp_send_init(struct sender *);
  36 extern void http_send_init(struct sender *);
  37 extern void ortp_send_init(struct sender *);
  38
  39 /** the list of supported senders */
  40 struct sender senders[] = {
  41         {
  42                 .name = "http",
  43                 .init = http_send_init,
  44         },
  45         {
  46                 .name = "dccp",
  47                 .init = dccp_send_init,
  48         },
  49 #ifdef HAVE_ORTP
  50         {
  51                 .name = "ortp",
  52                 .init = ortp_send_init,
  53         },
  54 #endif
  55         {
  56                 .name = NULL,
  57         }
  58 };
  59
  60 /** The possible states of the afs socket. See \ref afs_socket. */
  61 enum afs_socket_status {
  62         /** Socket is inactive. */
  63         AFS_SOCKET_READY,
  64         /** Socket fd was included in the write fd set for select(). */
  65         AFS_SOCKET_CHECK_FOR_WRITE,
  66         /** vss wrote a request to the socket and waits for afs to reply. */
  67         AFS_SOCKET_AFD_PENDING
  68 };
  69
  70 static char *map;
  71
  72 struct vss_task {
  73         struct timeval announce_tv;
  74         struct timeval data_send_barrier;
  75         struct timeval eof_barrier;
  76         struct timeval autoplay_barrier;
  77         enum afs_socket_status afsss;
  78 };
  79
  80 static struct vss_task vss_task_struct, *vsst = &vss_task_struct;
  81
  82 /**
  83  * Check if vss status flag \a P (playing) is set.
  84  *
  85  * \return Greater than zero if playing, zero otherwise.
  86  *
  87  */
  88 unsigned int vss_playing(void)
  89 {
  90         return mmd->new_vss_status_flags & VSS_PLAYING;
  91 }
  92
  93 /**
  94  * Check if the \a N (next) status flag is set.
  95  *
  96  * \return Greater than zero if set, zero if not.
  97  *
  98  */
  99 unsigned int vss_next(void)
 100 {
 101         return mmd->new_vss_status_flags & VSS_NEXT;
 102 }
 103
 104 /**
 105  * Check if a reposition request is pending.
 106  *
 107  * \return Greater than zero if true, zero otherwise.
 108  *
 109  */
 110 unsigned int vss_repos(void)
 111 {
 112         return mmd->new_vss_status_flags & VSS_REPOS;
 113 }
 114
 115 /**
 116  * Check if the vss is currently paused.
 117  *
 118  * \return Greater than zero if paused, zero otherwise.
 119  *
 120  */
 121 unsigned int vss_paused(void)
 122 {
 123         return !(mmd->new_vss_status_flags & VSS_NEXT)
 124                 && !(mmd->new_vss_status_flags & VSS_PLAYING);
 125 }
 126
 127 /**
 128  * Check if the vss is currently stopped.
 129  *
 130  * \return Greater than zero if paused, zero otherwise.
 131  *
 132  */
 133 unsigned int vss_stopped(void)
 134 {
 135         return (mmd->new_vss_status_flags & VSS_NEXT)
 136                 && !(mmd->new_vss_status_flags & VSS_PLAYING);
 137 }
 138
 139 /**
 140  * Get the data of the given chunk.
 141  *
 142  * \param chunk_num The number of the desired chunk.
 143  * \param buf Chunk data.
 144  * \param len Chunk length in bytes.
 145  *
 146  * \return Standard.
 147  */
 148 int vss_get_chunk(long unsigned chunk_num, char **buf, size_t *len)
 149 {
 150         if (!map || !vss_playing())
 151                 return -E_CHUNK;
 152         if (chunk_num >= mmd->afd.afhi.chunks_total)
 153                 return -E_CHUNK;
 154         afh_get_chunk(chunk_num, &mmd->afd.afhi, map, buf, len);
 155         return 1;
 156 }
 157
 158 /**
 159  * Initialize the virtual streaming system.
 160  *
 161  * This also initializes all supported senders and starts streaming
 162  * if the --autoplay command line flag was given.
 163  */
 164 void vss_init(void)
 165 {
 166         int i;
 167         char *hn = para_hostname(), *home = para_homedir();
 168         long unsigned announce_time = conf.announce_time_arg > 0?
 169                         conf.announce_time_arg : 300,
 170                 autoplay_delay = conf.autoplay_delay_arg > 0?
 171                         conf.autoplay_delay_arg : 0;
 172         ms2tv(announce_time, &vsst->announce_tv);
 173         PARA_INFO_LOG("announce timeval: %lums\n", tv2ms(&vsst->announce_tv));
 174         for (i = 0; senders[i].name; i++) {
 175                 PARA_NOTICE_LOG("initializing %s sender\n", senders[i].name);
 176                 senders[i].init(&senders[i]);
 177         }
 178         free(hn);
 179         free(home);
 180         mmd->sender_cmd_data.cmd_num = -1;
 181         if (conf.autoplay_given) {
 182                 struct timeval now, tmp;
 183                 mmd->vss_status_flags |= VSS_PLAYING;
 184                 mmd->new_vss_status_flags |= VSS_PLAYING;
 185                 gettimeofday(&now, NULL);
 186                 ms2tv(autoplay_delay, &tmp);
 187                 tv_add(&now, &tmp, &vsst->autoplay_barrier);
 188         }
 189 }
 190
 191 static int chk_barrier(const char *bname, const struct timeval *now,
 192                 const struct timeval *barrier, struct timeval *diff,
 193                 int print_log)
 194 {
 195         long ms;
 196
 197         if (tv_diff(now, barrier, diff) > 0)
 198                 return 1;
 199         ms = tv2ms(diff);
 200         if (print_log && ms)
 201                 PARA_DEBUG_LOG("%s barrier: %lims left\n", bname, ms);
 202         return -1;
 203 }
 204
 205 /*
 206  * != NULL: timeout for next chunk
 207  * NULL: nothing to do
 208  */
 209 static struct timeval *vss_compute_timeout(void)
 210 {
 211         static struct timeval the_timeout;
 212         struct timeval now, next_chunk;
 213
 214         if (vss_next() && map) {
 215                 /* only sleep a bit, nec*/
 216                 the_timeout.tv_sec = 0;
 217                 the_timeout.tv_usec = 100;
 218                 return &the_timeout;
 219         }
 220         gettimeofday(&now, NULL);
 221         if (chk_barrier("autoplay_delay", &now, &vsst->autoplay_barrier,
 222                         &the_timeout, 1) < 0)
 223                 return &the_timeout;
 224         if (chk_barrier("eof", &now, &vsst->eof_barrier, &the_timeout, 1) < 0)
 225                 return &the_timeout;
 226         if (chk_barrier("data send", &now, &vsst->data_send_barrier,
 227                         &the_timeout, 1) < 0)
 228                 return &the_timeout;
 229         if (!vss_playing() || !map)
 230                 return NULL;
 231         compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
 232                 &mmd->stream_start, &next_chunk);
 233         if (chk_barrier("chunk", &now, &next_chunk, &the_timeout, 0) < 0)
 234                 return &the_timeout;
 235         /* chunk is due or bof */
 236         the_timeout.tv_sec = 0;
 237         the_timeout.tv_usec = 0;
 238         return &the_timeout;
 239 }
 240
 241 static void vss_eof(void)
 242 {
 243         struct timeval now;
 244         char *tmp;
 245
 246         if (!map)
 247                 return;
 248         if (mmd->new_vss_status_flags & VSS_NOMORE)
 249                 mmd->new_vss_status_flags = VSS_NEXT;
 250         gettimeofday(&now, NULL);
 251         tv_add(&mmd->afd.afhi.eof_tv, &now, &vsst->eof_barrier);
 252         para_munmap(map, mmd->size);
 253         map = NULL;
 254         mmd->chunks_sent = 0;
 255         mmd->offset = 0;
 256         mmd->afd.afhi.seconds_total = 0;
 257         free(mmd->afd.afhi.chunk_table);
 258         mmd->afd.afhi.chunk_table = NULL;
 259         tmp  = make_message("%s:\n%s:\n%s:\n", status_item_list[SI_AUDIO_FILE_INFO],
 260                 status_item_list[SI_TAGINFO1], status_item_list[SI_TAGINFO2]);
 261         strncpy(mmd->afd.afhi.info_string, tmp, sizeof(mmd->afd.afhi.info_string));
 262         mmd->afd.afhi.info_string[sizeof(mmd->afd.afhi.info_string) - 1] = '\0';
 263         make_empty_status_items(mmd->afd.verbose_ls_output);
 264         free(tmp);
 265         mmd->mtime = 0;
 266         mmd->size = 0;
 267         mmd->events++;
 268 }
 269
 270 /**
 271  * Get the header of the current audio file.
 272  *
 273  * \param buf The length of the header is stored here.
 274  * \param len Points to a buffer containing the header on return.
 275  *
 276  * \sa afh_get_header.
 277  */
 278 void vss_get_header(char **buf, size_t *len)
 279 {
 280         afh_get_header(&mmd->afd.afhi, map, buf, len);
 281 }
 282
 283 /**
 284  * Get the list of all supported audio formats.
 285  *
 286  * \return Aa space separated list of all supported audio formats
 287  * It is not allocated at runtime, i.e. there is no need to free
 288  * the returned string in the caller.
 289  */
 290 const char *supported_audio_formats(void)
 291 {
 292         return SUPPORTED_AUDIO_FORMATS;
 293 }
 294
 295 /**
 296  * Get the chunk time of the current audio file.
 297  *
 298  * \return A pointer to a struct containing the chunk time, or NULL,
 299  * if currently no audio file is selected.
 300  */
 301 struct timeval *vss_chunk_time(void)
 302 {
 303         if (!map)
 304                 return NULL;
 305         return &mmd->afd.afhi.chunk_tv;
 306 }
 307
 308 static int need_to_request_new_audio_file(void)
 309 {
 310         if (map) /* have audio file */
 311                 return 0;
 312         if (!vss_playing()) /* don't need one */
 313                 return 0;
 314         if (mmd->new_vss_status_flags & VSS_NOMORE)
 315                 return 0;
 316         if (vsst->afsss == AFS_SOCKET_AFD_PENDING) /* already requested one */
 317                 return 0;
 318         return 1;
 319 }
 320
 321 /**
 322  * Compute the timeout for para_server's main select-loop.
 323  *
 324  * This function gets called from para_server to determine the timeout value
 325  * for its main select loop.
 326  *
 327  * \param rfds The set of file descriptors to be checked for reading.
 328  * \param wfds The set of file descriptors to be checked for writing.
 329  * \param max_fileno The highest-numbered file descriptor.
 330  *
 331  * Before the timeout is computed, the current vss status flags are evaluated
 332  * and acted upon by calling appropriate functions from the lower layers.
 333  * Possible actions include
 334  *
 335  *      - request a new audio file from afs,
 336  *      - shutdown of all senders (stop/pause command),
 337  *      - reposition the stream (ff/jmp command).
 338  *
 339  * \return A pointer to a struct timeval containing the timeout for the next
 340  * chunk of data to be sent, or NULL if we're not sending right now.
 341  */
 342 struct timeval *vss_preselect(fd_set *rfds, fd_set *wfds, int *max_fileno)
 343 {
 344         int i;
 345         struct timeval now;
 346
 347         if (!map || vss_next() || vss_paused() || vss_repos())
 348                 for (i = 0; senders[i].name; i++)
 349                         senders[i].shutdown_clients();
 350         if (vss_next())
 351                 vss_eof();
 352         else if (vss_paused()) {
 353                 if (mmd->chunks_sent) {
 354                         gettimeofday(&now, NULL);
 355                         tv_add(&mmd->afd.afhi.eof_tv, &now, &vsst->eof_barrier);
 356                 }
 357                 mmd->chunks_sent = 0;
 358         } else if (vss_repos()) {
 359                 gettimeofday(&now, NULL);
 360                 tv_add(&now, &vsst->announce_tv, &vsst->data_send_barrier);
 361                 tv_add(&mmd->afd.afhi.eof_tv, &now, &vsst->eof_barrier);
 362                 mmd->chunks_sent = 0;
 363                 mmd->current_chunk = mmd->repos_request;
 364                 mmd->new_vss_status_flags &= ~VSS_REPOS;
 365         }
 366
 367         if (need_to_request_new_audio_file()) {
 368                 PARA_DEBUG_LOG("ready and playing, but no audio file\n");
 369                 para_fd_set(afs_socket, wfds, max_fileno);
 370                 vsst->afsss = AFS_SOCKET_CHECK_FOR_WRITE;
 371         } else
 372                 para_fd_set(afs_socket, rfds, max_fileno);
 373         for (i = 0; senders[i].name; i++) {
 374                 if (!senders[i].pre_select)
 375                         continue;
 376                 senders[i].pre_select(max_fileno, rfds, wfds);
 377         }
 378         return vss_compute_timeout();
 379 }
 380
 381 static int recv_afs_msg(int *fd, uint32_t *code, uint32_t *data)
 382 {
 383         char control[255], buf[8];
 384         struct msghdr msg = {.msg_iov = NULL};
 385         struct cmsghdr *cmsg;
 386         struct iovec iov;
 387         int ret = 0;
 388
 389         *fd = -1;
 390         iov.iov_base = buf;
 391         iov.iov_len = sizeof(buf);
 392         msg.msg_iov = &iov;
 393         msg.msg_iovlen = 1;
 394         msg.msg_control = control;
 395         msg.msg_controllen = sizeof(control);
 396         memset(buf, 0, sizeof(buf));
 397         ret = recvmsg(afs_socket, &msg, 0);
 398         if (ret < 0)
 399                 return -ERRNO_TO_PARA_ERROR(errno);
 400         vsst->afsss = AFS_SOCKET_READY;
 401         if (iov.iov_len != sizeof(buf))
 402                 return -E_AFS_SHORT_READ;
 403         *code = *(uint32_t*)buf;
 404         *data =  *(uint32_t*)(buf + 4);
 405         for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
 406                 if (cmsg->cmsg_level != SOL_SOCKET
 407                         || cmsg->cmsg_type != SCM_RIGHTS)
 408                 continue;
 409                 if ((cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int) != 1)
 410                 continue;
 411                 *fd = *(int *)CMSG_DATA(cmsg);
 412         }
 413         return 1;
 414 }
 415
 416 static void recv_afs_result(void)
 417 {
 418         int ret, passed_fd, shmid;
 419         uint32_t afs_code = 0, afs_data = 0;
 420         struct stat statbuf;
 421         struct timeval now;
 422
 423         mmd->afd.afhi.chunk_table = NULL;
 424         ret = recv_afs_msg(&passed_fd, &afs_code, &afs_data);
 425         if (ret < 0)
 426                 goto err;
 427         PARA_DEBUG_LOG("fd: %d, code: %u, shmid: %u\n", passed_fd, afs_code,
 428                 afs_data);
 429         ret = -E_NOFD;
 430         if (afs_code != NEXT_AUDIO_FILE)
 431                 goto err;
 432         if (passed_fd < 0)
 433                 goto err;
 434         shmid = afs_data;
 435         ret = load_afd(shmid, &mmd->afd);
 436         if (ret < 0)
 437                 goto err;
 438         shm_destroy(shmid);
 439         ret = fstat(passed_fd, &statbuf);
 440         if (ret < 0) {
 441                 PARA_ERROR_LOG("fstat error:\n");
 442                 ret = -ERRNO_TO_PARA_ERROR(errno);
 443                 goto err;
 444         }
 445         mmd->size = statbuf.st_size;
 446         mmd->mtime = statbuf.st_mtime;
 447         map = para_mmap(mmd->size, PROT_READ, MAP_PRIVATE,
 448                 passed_fd, 0);
 449         close(passed_fd);
 450         mmd->chunks_sent = 0;
 451         mmd->current_chunk = 0;
 452         mmd->offset = 0;
 453         mmd->events++;
 454         mmd->num_played++;
 455         mmd->new_vss_status_flags &= (~VSS_NEXT);
 456         gettimeofday(&now, NULL);
 457         tv_add(&now, &vsst->announce_tv, &vsst->data_send_barrier);
 458         return;
 459 err:
 460         free(mmd->afd.afhi.chunk_table);
 461         if (passed_fd >= 0)
 462                 close(passed_fd);
 463         PARA_ERROR_LOG("%s\n", para_strerror(-ret));
 464         mmd->new_vss_status_flags = VSS_NEXT;
 465 }
 466
 467 /**
 468  * Main sending function.
 469  *
 470  * This function gets called from para_server as soon as the next chunk of data
 471  * should be pushed out. It obtains a pointer to the data to be sent out as
 472  * well as its length from mmd->afd.afhi. This information is then passed to
 473  * each supported sender's send() function which is supposed to send out the data
 474  * to all connected clients.
 475  */
 476 static void vss_send_chunk(void)
 477 {
 478         int i;
 479         struct timeval now, due;
 480         char *buf;
 481         size_t len;
 482
 483         if (!map || !vss_playing())
 484                 return;
 485         gettimeofday(&now, NULL);
 486         compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
 487                 &mmd->stream_start, &due);
 488         if (tv_diff(&due, &now, NULL) > 0)
 489                 return;
 490         if (chk_barrier("eof", &now, &vsst->eof_barrier, &due, 1) < 0)
 491                 return;
 492         if (chk_barrier("data send", &now, &vsst->data_send_barrier,
 493                         &due, 1) < 0)
 494                 return;
 495         mmd->new_vss_status_flags &= ~VSS_REPOS;
 496         if (mmd->current_chunk >= mmd->afd.afhi.chunks_total) { /* eof */
 497                 mmd->new_vss_status_flags |= VSS_NEXT;
 498                 return;
 499         }
 500         /*
 501          * We call the send function also in case of empty chunks as they
 502          * might have still some data queued which can be sent in this case.
 503          */
 504         if (!mmd->chunks_sent) {
 505                 struct timeval tmp;
 506                 gettimeofday(&mmd->stream_start, NULL);
 507                 tv_scale(mmd->current_chunk, &mmd->afd.afhi.chunk_tv, &tmp);
 508                 mmd->offset = tv2ms(&tmp);
 509                 mmd->events++;
 510         }
 511         afh_get_chunk(mmd->current_chunk, &mmd->afd.afhi, map, &buf, &len);
 512         for (i = 0; senders[i].name; i++)
 513                 senders[i].send(mmd->current_chunk, mmd->chunks_sent, buf, len);
 514         mmd->new_vss_status_flags |= VSS_PLAYING;
 515         mmd->chunks_sent++;
 516         mmd->current_chunk++;
 517 }
 518
 519 void vss_post_select(fd_set *rfds, fd_set *wfds)
 520 {
 521         int ret, i;
 522
 523         if (mmd->sender_cmd_data.cmd_num >= 0) {
 524                 int num = mmd->sender_cmd_data.cmd_num,
 525                         s = mmd->sender_cmd_data.sender_num;
 526
 527                 if (senders[s].client_cmds[num])
 528                         senders[s].client_cmds[num](&mmd->sender_cmd_data);
 529                 mmd->sender_cmd_data.cmd_num = -1;
 530         }
 531         if (vsst->afsss != AFS_SOCKET_CHECK_FOR_WRITE) {
 532                 if (FD_ISSET(afs_socket, rfds))
 533                         recv_afs_result();
 534         } else if (FD_ISSET(afs_socket, wfds)) {
 535                 PARA_NOTICE_LOG("requesting new fd from afs\n");
 536                 ret = send_buffer(afs_socket, "new");
 537                 vsst->afsss = AFS_SOCKET_AFD_PENDING;
 538         }
 539         for (i = 0; senders[i].name; i++) {
 540                 if (!senders[i].post_select)
 541                         continue;
 542                 senders[i].post_select(rfds, wfds);
 543         }
 544         vss_send_chunk();
 545 }