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