vss.c

   1 /*
   2  * Copyright (C) 1997-2007 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 "send.h"
  29 #include "ipc.h"
  30 #include "fd.h"
  31
  32 extern const char *status_item_list[];
  33
  34 static struct timeval announce_tv;
  35 static struct timeval data_send_barrier;
  36 static struct timeval eof_barrier;
  37 static struct timeval autoplay_barrier;
  38
  39 extern struct misc_meta_data *mmd;
  40 extern struct sender senders[];
  41
  42 static char *map;
  43
  44 /**
  45  * Check if vss status flag \a P (playing) is set.
  46  *
  47  * \return Greater than zero if playing, zero otherwise.
  48  *
  49  */
  50 unsigned int vss_playing(void)
  51 {
  52         return mmd->new_vss_status_flags & VSS_PLAYING;
  53 }
  54
  55 /**
  56  * Check if the \a N (next) status flag is set.
  57  *
  58  * \return Greater than zero if set, zero if not.
  59  *
  60  */
  61 unsigned int vss_next(void)
  62 {
  63         return mmd->new_vss_status_flags & VSS_NEXT;
  64 }
  65
  66 /**
  67  * Check if a reposition request is pending.
  68  *
  69  * \return Greater than zero if true, zero otherwise.
  70  *
  71  */
  72 unsigned int vss_repos(void)
  73 {
  74         return mmd->new_vss_status_flags & VSS_REPOS;
  75 }
  76
  77 /**
  78  * Check if the vss is currently paused.
  79  *
  80  * \return Greater than zero if paused, zero otherwise.
  81  *
  82  */
  83 unsigned int vss_paused(void)
  84 {
  85         return !(mmd->new_vss_status_flags & VSS_NEXT)
  86                 && !(mmd->new_vss_status_flags & VSS_PLAYING);
  87 }
  88
  89 /**
  90  * Initialize the virtual streaming system.
  91  *
  92  * This also initializes all supported senders and starts streaming
  93  * if the --autoplay command line flag was given.
  94  */
  95 void vss_init(void)
  96 {
  97         int i;
  98         char *hn = para_hostname(), *home = para_homedir();
  99         long unsigned announce_time = conf.announce_time_arg > 0?
 100                         conf.announce_time_arg : 300,
 101                 autoplay_delay = conf.autoplay_delay_arg > 0?
 102                         conf.autoplay_delay_arg : 0;
 103         ms2tv(announce_time, &announce_tv);
 104         PARA_INFO_LOG("announce timeval: %lums\n", tv2ms(&announce_tv));
 105         for (i = 0; senders[i].name; i++) {
 106                 PARA_NOTICE_LOG("initializing %s sender\n", senders[i].name);
 107                 senders[i].init(&senders[i]);
 108         }
 109         free(hn);
 110         free(home);
 111         if (conf.autoplay_given) {
 112                 struct timeval now, tmp;
 113                 mmd->vss_status_flags |= VSS_PLAYING;
 114                 mmd->new_vss_status_flags |= VSS_PLAYING;
 115                 gettimeofday(&now, NULL);
 116                 ms2tv(autoplay_delay, &tmp);
 117                 tv_add(&now, &tmp, &autoplay_barrier);
 118         }
 119 }
 120
 121 static int chk_barrier(const char *bname, const struct timeval *now,
 122                 const struct timeval *barrier, struct timeval *diff,
 123                 int print_log)
 124 {
 125         long ms;
 126
 127         if (tv_diff(now, barrier, diff) > 0)
 128                 return 1;
 129         ms = tv2ms(diff);
 130         if (print_log && ms)
 131                 PARA_DEBUG_LOG("%s barrier: %lims left\n", bname, ms);
 132         return -1;
 133 }
 134
 135 static void vss_next_chunk_time(struct timeval *due)
 136 {
 137         struct timeval tmp;
 138
 139         tv_scale(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv, &tmp);
 140         tv_add(&tmp, &mmd->stream_start, due);
 141 }
 142
 143 /*
 144  * != NULL: timeout for next chunk
 145  * NULL: nothing to do
 146  */
 147 static struct timeval *vss_compute_timeout(void)
 148 {
 149         static struct timeval the_timeout;
 150         struct timeval now, next_chunk;
 151
 152         if (vss_next() && map) {
 153                 /* only sleep a bit, nec*/
 154                 the_timeout.tv_sec = 0;
 155                 the_timeout.tv_usec = 100;
 156                 return &the_timeout;
 157         }
 158         gettimeofday(&now, NULL);
 159         if (chk_barrier("autoplay_delay", &now, &autoplay_barrier,
 160                         &the_timeout, 1) < 0)
 161                 return &the_timeout;
 162         if (chk_barrier("eof", &now, &eof_barrier, &the_timeout, 1) < 0)
 163                 return &the_timeout;
 164         if (chk_barrier("data send", &now, &data_send_barrier,
 165                         &the_timeout, 1) < 0)
 166                 return &the_timeout;
 167         if (!vss_playing() || !map)
 168                 return NULL;
 169         vss_next_chunk_time(&next_chunk);
 170         if (chk_barrier(audio_format_name(mmd->afd.afsi.audio_format_id),
 171                         &now, &next_chunk, &the_timeout, 0) < 0)
 172                 return &the_timeout;
 173         /* chunk is due or bof */
 174         the_timeout.tv_sec = 0;
 175         the_timeout.tv_usec = 0;
 176         return &the_timeout;
 177 }
 178
 179 static void vss_eof(void)
 180 {
 181         struct timeval now;
 182         int i;
 183         char *tmp;
 184
 185         if (!map) {
 186                 for (i = 0; senders[i].name; i++)
 187                         senders[i].shutdown_clients();
 188                 return;
 189         }
 190         gettimeofday(&now, NULL);
 191         tv_add(&mmd->afd.afhi.eof_tv, &now, &eof_barrier);
 192         munmap(map, mmd->size);
 193         map = NULL;
 194         mmd->chunks_sent = 0;
 195         mmd->offset = 0;
 196         mmd->afd.afhi.seconds_total = 0;
 197         free(mmd->afd.afhi.chunk_table);
 198         mmd->afd.afhi.chunk_table = NULL;
 199         tmp  = make_message("%s:\n%s:\n%s:\n", status_item_list[SI_AUDIO_INFO1],
 200                 status_item_list[SI_AUDIO_INFO2], status_item_list[SI_AUDIO_INFO3]);
 201         strncpy(mmd->afd.afhi.info_string, tmp, sizeof(mmd->afd.afhi.info_string));
 202         mmd->afd.afhi.info_string[sizeof(mmd->afd.afhi.info_string) - 1] = '\0';
 203         free(tmp);
 204         mmd->afd.afsi.lyrics_id = 0;
 205         mmd->afd.afsi.image_id = 0;
 206         mmd->mtime = 0;
 207         mmd->size = 0;
 208         mmd->events++;
 209 }
 210
 211 /**
 212  * Get the header of the current audio file.
 213  *
 214  * \param header_len The length of the header is stored here.
 215  *
 216  * \return A pointer to a buffer containing the header, or NULL, if no audio
 217  * file is selected or if the current audio format does not need special header
 218  * treamtment.
 219  *
 220  */
 221 char *vss_get_header(size_t *header_len)
 222 {
 223         if (!map || !mmd->afd.afhi.header_len)
 224                 return NULL;
 225         *header_len = mmd->afd.afhi.header_len;
 226         return map + mmd->afd.afhi.header_offset;
 227 }
 228
 229 /**
 230  * Get the list of all supported audio formats.
 231  *
 232  * \return Aa space separated list of all supported audio formats
 233  * It is not allocated at runtime, i.e. there is no need to free
 234  * the returned string in the caller.
 235  */
 236 const char *supported_audio_formats(void)
 237 {
 238         return SUPPORTED_AUDIO_FORMATS;
 239 }
 240
 241 /**
 242  * Get the chunk time of the current audio file.
 243  *
 244  * \return A pointer to a struct containing the chunk time, or NULL,
 245  * if currently no audio file is selected.
 246  */
 247 struct timeval *vss_chunk_time(void)
 248 {
 249         if (!map)
 250                 return NULL;
 251         return &mmd->afd.afhi.chunk_tv;
 252 }
 253
 254 enum afs_socket_status {
 255         AFS_SOCKET_READY,
 256         AFS_SOCKET_CHECK_FOR_WRITE,
 257         AFS_SOCKET_AFD_PENDING
 258 };
 259
 260 static enum afs_socket_status afsss;
 261
 262 /**
 263  * Compute the timeout for para_server's main select-loop.
 264  *
 265  * This function gets called from para_server to determine the timeout value
 266  * for its main select loop.
 267  *
 268  * \param rfds The set of file descriptors to be checked for reading.
 269  * \param wfds The set of file descriptors to be checked for writing.
 270  * \param max_fileno The highest-numbered file descriptor.
 271  *
 272  * Before the timeout is computed, the current vss status flags are evaluated
 273  * and acted upon by calling appropriate functions from the lower layers.
 274  * Possible actions include
 275  *
 276  *      - request a new audio file from afs,
 277  *      - shutdown of all senders (stop/pause command),
 278  *      - reposition the stream (ff/jmp command).
 279  *
 280  * \return A pointer to a struct timeval containing the timeout for the next
 281  * chunk of data to be sent, or NULL if we're not sending right now.
 282  */
 283 struct timeval *vss_preselect(fd_set *rfds, fd_set *wfds, int *max_fileno)
 284 {
 285         int i;
 286         struct timeval *tv;
 287
 288         para_fd_set(afs_socket, rfds, max_fileno);
 289         if (!map)
 290                 for (i = 0; senders[i].name; i++)
 291                         senders[i].shutdown_clients();
 292         else {
 293                 if (vss_next()) {
 294                         vss_eof();
 295                         return vss_compute_timeout();
 296                 }
 297         }
 298         if (vss_paused() || vss_repos()) {
 299                 for (i = 0; senders[i].name; i++)
 300                         senders[i].shutdown_clients();
 301                 if (map) {
 302                         struct timeval now;
 303                         gettimeofday(&now, NULL);
 304                         if (!vss_paused() || mmd->chunks_sent)
 305                                 tv_add(&mmd->afd.afhi.eof_tv, &now, &eof_barrier);
 306                         if (vss_repos())
 307                                 tv_add(&now, &announce_tv, &data_send_barrier);
 308                         if (mmd->new_vss_status_flags & VSS_NOMORE)
 309                                 mmd->new_vss_status_flags = VSS_NEXT;
 310                 }
 311                 mmd->chunks_sent = 0;
 312         }
 313         if (vss_repos()) {
 314                 mmd->new_vss_status_flags &= ~(VSS_REPOS);
 315                 mmd->current_chunk = mmd->repos_request;
 316         }
 317         tv = vss_compute_timeout();
 318         if (tv)
 319                 return tv;
 320         if (!map && vss_playing() &&
 321                         !(mmd->new_vss_status_flags & VSS_NOMORE)) {
 322                 if (afsss == AFS_SOCKET_READY ||
 323                                 afsss == AFS_SOCKET_CHECK_FOR_WRITE) {
 324                         PARA_DEBUG_LOG("ready and playing, but no audio file\n");
 325                         para_fd_set(afs_socket, wfds, max_fileno);
 326                         afsss = AFS_SOCKET_CHECK_FOR_WRITE;
 327                 }
 328         }
 329         return tv;
 330 }
 331
 332 static int recv_afs_msg(int *fd, uint32_t *code, uint32_t *data)
 333 {
 334         char control[255], buf[8];
 335         struct msghdr msg = {.msg_iov = NULL};
 336         struct cmsghdr *cmsg;
 337         struct iovec iov;
 338         int ret = 0;
 339
 340         iov.iov_base = buf;
 341         iov.iov_len = sizeof(buf);
 342         msg.msg_iov = &iov;
 343         msg.msg_iovlen = 1;
 344         msg.msg_control = control;
 345         msg.msg_controllen = sizeof(control);
 346         memset(buf, 0, sizeof(buf));
 347         ret = recvmsg(afs_socket, &msg, 0);
 348         if (ret < 0)
 349                 return -ERRNO_TO_PARA_ERROR(errno);
 350         if (iov.iov_len != sizeof(buf))
 351                 return -E_SHORT_AFS_READ;
 352         *code = *(uint32_t*)buf;
 353         *data =  *(uint32_t*)(buf + 4);
 354         for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
 355                 if (cmsg->cmsg_level != SOL_SOCKET
 356                         || cmsg->cmsg_type != SCM_RIGHTS)
 357                 continue;
 358                 if ((cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int) != 1)
 359                 continue;
 360                 *fd = *(int *)CMSG_DATA(cmsg);
 361         }
 362         return 1;
 363 }
 364
 365 static void recv_afs_result(void)
 366 {
 367         int ret, passed_fd = -1, shmid;
 368         uint32_t afs_code = 0, afs_data = 0;
 369         struct stat statbuf;
 370         struct timeval now;
 371
 372         ret = recv_afs_msg(&passed_fd, &afs_code, &afs_data);
 373         if (ret < 0)
 374                 goto err;
 375         PARA_DEBUG_LOG("got the fd: %d, code: %u, shmid: %u\n",
 376                 passed_fd, afs_code, afs_data);
 377         ret = -E_BAD_AFS_CODE;
 378         if (afs_code != NEXT_AUDIO_FILE)
 379                 goto err;
 380         afsss = AFS_SOCKET_READY;
 381         shmid = afs_data;
 382         ret = load_afd(shmid, &mmd->afd);
 383         if (ret < 0)
 384                 goto err;
 385         shm_destroy(shmid);
 386         ret = fstat(passed_fd, &statbuf);
 387         if (ret < 0) {
 388                 PARA_ERROR_LOG("fstat error:\n");
 389                 ret = -ERRNO_TO_PARA_ERROR(errno);
 390                 goto err;
 391         }
 392         mmd->size = statbuf.st_size;
 393         mmd->mtime = statbuf.st_mtime;
 394         map = para_mmap(mmd->size, PROT_READ, MAP_PRIVATE,
 395                 passed_fd, 0);
 396         close(passed_fd);
 397         mmd->chunks_sent = 0;
 398         mmd->current_chunk = 0;
 399         mmd->offset = 0;
 400         mmd->events++;
 401         mmd->num_played++;
 402         mmd->new_vss_status_flags &= (~VSS_NEXT);
 403         gettimeofday(&now, NULL);
 404         tv_add(&now, &announce_tv, &data_send_barrier);
 405         return;
 406 err:
 407         if (passed_fd >= 0)
 408                 close(passed_fd);
 409         PARA_ERROR_LOG("%s\n", PARA_STRERROR(-ret));
 410 }
 411
 412 void vss_post_select(fd_set *rfds, fd_set *wfds)
 413 {
 414         int ret;
 415
 416         if (FD_ISSET(afs_socket, rfds))
 417                 recv_afs_result();
 418         if (afsss != AFS_SOCKET_CHECK_FOR_WRITE || !FD_ISSET(afs_socket, wfds))
 419                 return;
 420         PARA_NOTICE_LOG("requesting new fd from afs\n");
 421         ret = send_buffer(afs_socket, "new");
 422         afsss = AFS_SOCKET_AFD_PENDING;
 423 }
 424
 425 static void get_chunk(long unsigned chunk_num, char **buf, size_t *len)
 426 {
 427         size_t pos = mmd->afd.afhi.chunk_table[chunk_num];
 428         *buf = map + pos;
 429         *len = mmd->afd.afhi.chunk_table[chunk_num + 1] - pos;
 430 }
 431
 432 /**
 433  * Get the data of the given chunk.
 434  *
 435  * \param chunk_num The number of the desired chunk.
 436  * \param buf Chunk data.
 437  * \param len Chunk length in bytes.
 438  *
 439  * \return Standard.
 440  */
 441 int vss_get_chunk(long unsigned chunk_num, char **buf, size_t *len)
 442 {
 443         if (!map || !vss_playing())
 444                 return -E_CHUNK;
 445         if (chunk_num >= mmd->afd.afhi.chunks_total)
 446                 return -E_CHUNK;
 447         get_chunk(chunk_num, buf, len);
 448         return 1;
 449 }
 450
 451 /**
 452  * Main sending function.
 453  *
 454  * This function gets called from para_server as soon as the next chunk of data
 455  * should be pushed out. It obtains a pointer to the data to be sent out as
 456  * well as its length from mmd->afd.afhi. This information is then passed to
 457  * each supported sender's send() function which is supposed to send out the data
 458  * to all connected clients.
 459  */
 460 void vss_send_chunk(void)
 461 {
 462         int i;
 463         struct timeval now, due;
 464         char *buf;
 465         size_t len;
 466
 467         if (!map || !vss_playing())
 468                 return;
 469         gettimeofday(&now, NULL);
 470         vss_next_chunk_time(&due);
 471         if (tv_diff(&due, &now, NULL) > 0)
 472                 return;
 473         if (chk_barrier("eof", &now, &eof_barrier, &due, 1) < 0)
 474                 return;
 475         if (chk_barrier("data send", &now, &data_send_barrier,
 476                         &due, 1) < 0)
 477                 return;
 478         mmd->new_vss_status_flags &= ~VSS_REPOS;
 479         if (mmd->current_chunk >= mmd->afd.afhi.chunks_total) { /* eof */
 480                 mmd->new_vss_status_flags |= VSS_NEXT;
 481                 return vss_eof();
 482         }
 483         /*
 484          * We call the send function also in case of empty chunks as they
 485          * might have still some data queued which can be sent in this case.
 486          */
 487         if (!mmd->chunks_sent) {
 488                 struct timeval tmp;
 489                 gettimeofday(&mmd->stream_start, NULL);
 490                 tv_scale(mmd->current_chunk, &mmd->afd.afhi.chunk_tv, &tmp);
 491                 mmd->offset = tv2ms(&tmp);
 492                 mmd->events++;
 493         }
 494         get_chunk(mmd->current_chunk, &buf, &len);
 495         for (i = 0; senders[i].name; i++)
 496                 senders[i].send(mmd->current_chunk, mmd->chunks_sent, buf, len);
 497         mmd->new_vss_status_flags |= VSS_PLAYING;
 498         mmd->chunks_sent++;
 499         mmd->current_chunk++;
 500 }