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