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.path[0] = '\0';
 205         mmd->afd.afsi.lyrics_id = 0;
 206         mmd->afd.afsi.image_id = 0;
 207         mmd->mtime = 0;
 208         mmd->afd.attributes_string[0] = '\0';
 209         mmd->size = 0;
 210         mmd->events++;
 211 }
 212
 213 /**
 214  * Get the header of the current audio file.
 215  *
 216  * \param header_len The length of the header is stored here.
 217  *
 218  * \return A pointer to a buffer containing the header, or NULL, if no audio
 219  * file is selected or if the current audio format does not need special header
 220  * treamtment.
 221  *
 222  */
 223 char *vss_get_header(size_t *header_len)
 224 {
 225         if (!map || !mmd->afd.afhi.header_len)
 226                 return NULL;
 227         *header_len = mmd->afd.afhi.header_len;
 228         return map + mmd->afd.afhi.header_offset;
 229 }
 230
 231 /**
 232  * Get the list of all supported audio formats.
 233  *
 234  * \return Aa space separated list of all supported audio formats
 235  * It is not allocated at runtime, i.e. there is no need to free
 236  * the returned string in the caller.
 237  */
 238 const char *supported_audio_formats(void)
 239 {
 240         return SUPPORTED_AUDIO_FORMATS;
 241 }
 242
 243 /**
 244  * Get the chunk time of the current audio file.
 245  *
 246  * \return A pointer to a struct containing the chunk time, or NULL,
 247  * if currently no audio file is selected.
 248  */
 249 struct timeval *vss_chunk_time(void)
 250 {
 251         if (!map)
 252                 return NULL;
 253         return &mmd->afd.afhi.chunk_tv;
 254 }
 255
 256 enum afs_socket_status {
 257         AFS_SOCKET_READY,
 258         AFS_SOCKET_CHECK_FOR_WRITE,
 259         AFS_SOCKET_AFD_PENDING
 260 };
 261
 262 static enum afs_socket_status afsss;
 263
 264 /**
 265  * Compute the timeout for para_server's main select-loop.
 266  *
 267  * This function gets called from para_server to determine the timeout value
 268  * for its main select loop.
 269  *
 270  * \param rfds The set of file descriptors to be checked for reading.
 271  * \param wfds The set of file descriptors to be checked for writing.
 272  * \param max_fileno The highest-numbered file descriptor.
 273  *
 274  * Before the timeout is computed, the current vss status flags are evaluated
 275  * and acted upon by calling appropriate functions from the lower layers.
 276  * Possible actions include
 277  *
 278  *      - request a new audio file from afs,
 279  *      - shutdown of all senders (stop/pause command),
 280  *      - reposition the stream (ff/jmp command).
 281  *
 282  * \return A pointer to a struct timeval containing the timeout for the next
 283  * chunk of data to be sent, or NULL if we're not sending right now.
 284  */
 285 struct timeval *vss_preselect(fd_set *rfds, fd_set *wfds, int *max_fileno)
 286 {
 287         int i;
 288         struct timeval *tv;
 289
 290         para_fd_set(afs_socket, rfds, max_fileno);
 291         if (!map)
 292                 for (i = 0; senders[i].name; i++)
 293                         senders[i].shutdown_clients();
 294         else {
 295                 if (vss_next()) {
 296                         vss_eof();
 297                         return vss_compute_timeout();
 298                 }
 299         }
 300         if (vss_paused() || vss_repos()) {
 301                 for (i = 0; senders[i].name; i++)
 302                         senders[i].shutdown_clients();
 303                 if (map) {
 304                         struct timeval now;
 305                         gettimeofday(&now, NULL);
 306                         if (!vss_paused() || mmd->chunks_sent)
 307                                 tv_add(&mmd->afd.afhi.eof_tv, &now, &eof_barrier);
 308                         if (vss_repos())
 309                                 tv_add(&now, &announce_tv, &data_send_barrier);
 310                         if (mmd->new_vss_status_flags & VSS_NOMORE)
 311                                 mmd->new_vss_status_flags = VSS_NEXT;
 312                 }
 313                 mmd->chunks_sent = 0;
 314         }
 315         if (vss_repos()) {
 316                 mmd->new_vss_status_flags &= ~(VSS_REPOS);
 317                 mmd->current_chunk = mmd->repos_request;
 318         }
 319         tv = vss_compute_timeout();
 320         if (tv)
 321                 return tv;
 322         if (!map && vss_playing() &&
 323                         !(mmd->new_vss_status_flags & VSS_NOMORE)) {
 324                 if (afsss == AFS_SOCKET_READY) {
 325                         PARA_DEBUG_LOG("ready and playing, but no audio file\n");
 326                         para_fd_set(afs_socket, wfds, max_fileno);
 327                         afsss = AFS_SOCKET_CHECK_FOR_WRITE;
 328                 }
 329         }
 330         return tv;
 331 }
 332
 333 static int recv_afs_msg(int *fd, uint32_t *code, uint32_t *data)
 334 {
 335         char control[255], buf[8];
 336         struct msghdr msg = {.msg_iov = NULL};
 337         struct cmsghdr *cmsg;
 338         struct iovec iov;
 339         int ret = 0;
 340
 341         iov.iov_base = buf;
 342         iov.iov_len = sizeof(buf);
 343         msg.msg_iov = &iov;
 344         msg.msg_iovlen = 1;
 345         msg.msg_control = control;
 346         msg.msg_controllen = sizeof(control);
 347         memset(buf, 0, sizeof(buf));
 348         ret = recvmsg(afs_socket, &msg, 0);
 349         if (ret < 0)
 350                 return -ERRNO_TO_PARA_ERROR(errno);
 351         if (iov.iov_len != sizeof(buf))
 352                 return -E_SHORT_AFS_READ;
 353         *code = *(uint32_t*)buf;
 354         *data =  *(uint32_t*)(buf + 4);
 355         for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
 356                 if (cmsg->cmsg_level != SOL_SOCKET
 357                         || cmsg->cmsg_type != SCM_RIGHTS)
 358                 continue;
 359                 if ((cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int) != 1)
 360                 continue;
 361                 *fd = *(int *)CMSG_DATA(cmsg);
 362         }
 363         return 1;
 364 }
 365
 366 static void recv_afs_result(void)
 367 {
 368         int ret, passed_fd = -1, shmid;
 369         uint32_t afs_code = 0, afs_data = 0;
 370         struct stat statbuf;
 371         struct timeval now;
 372
 373         ret = recv_afs_msg(&passed_fd, &afs_code, &afs_data);
 374         if (ret < 0)
 375                 goto err;
 376         PARA_DEBUG_LOG("got the fd: %d, code: %u, shmid: %u\n",
 377                 passed_fd, afs_code, afs_data);
 378         ret = -E_BAD_AFS_CODE;
 379         if (afs_code != NEXT_AUDIO_FILE)
 380                 goto err;
 381         afsss = AFS_SOCKET_READY;
 382         shmid = afs_data;
 383         ret = load_afd(shmid, &mmd->afd);
 384         if (ret < 0)
 385                 goto err;
 386         shm_destroy(shmid);
 387         PARA_NOTICE_LOG("next audio file: %s (%lu chunks)\n", mmd->afd.path,
 388                 mmd->afd.afhi.chunks_total);
 389         ret = fstat(passed_fd, &statbuf);
 390         if (ret < 0) {
 391                 PARA_ERROR_LOG("fstat error:\n");
 392                 ret = -ERRNO_TO_PARA_ERROR(errno);
 393                 goto err;
 394         }
 395         mmd->size = statbuf.st_size;
 396         mmd->mtime = statbuf.st_mtime;
 397         map = para_mmap(mmd->size, PROT_READ, MAP_PRIVATE,
 398                 passed_fd, 0);
 399         close(passed_fd);
 400         mmd->afd.afhi.header_len = 0; /* default: no header */
 401         mmd->chunks_sent = 0;
 402         mmd->current_chunk = 0;
 403         mmd->offset = 0;
 404         mmd->events++;
 405         mmd->num_played++;
 406         mmd->new_vss_status_flags &= (~VSS_NEXT);
 407         gettimeofday(&now, NULL);
 408         tv_add(&now, &announce_tv, &data_send_barrier);
 409         return;
 410 err:
 411         if (passed_fd >= 0)
 412                 close(passed_fd);
 413         PARA_ERROR_LOG("%s\n", PARA_STRERROR(-ret));
 414 }
 415
 416 void vss_post_select(fd_set *rfds, fd_set *wfds)
 417 {
 418         int ret;
 419
 420         if (FD_ISSET(afs_socket, rfds))
 421                 recv_afs_result();
 422         if (afsss != AFS_SOCKET_CHECK_FOR_WRITE || !FD_ISSET(afs_socket, wfds))
 423                 return;
 424         PARA_NOTICE_LOG("requesting new fd from afs\n");
 425         ret = send_buffer(afs_socket, "new");
 426         afsss = AFS_SOCKET_AFD_PENDING;
 427 }
 428
 429 static void get_chunk(long unsigned chunk_num, char **buf, size_t *len)
 430 {
 431         size_t pos = mmd->afd.afhi.chunk_table[chunk_num];
 432         *buf = map + pos;
 433         *len = mmd->afd.afhi.chunk_table[chunk_num + 1] - pos;
 434 }
 435
 436 /**
 437  * Get the data of the given chunk.
 438  *
 439  * \param chunk_num The number of the desired chunk.
 440  * \param buf Chunk data.
 441  * \param len Chunk length in bytes.
 442  *
 443  * \return Standard.
 444  */
 445 int vss_get_chunk(long unsigned chunk_num, char **buf, size_t *len)
 446 {
 447         if (!map || !vss_playing())
 448                 return -E_CHUNK;
 449         if (chunk_num >= mmd->afd.afhi.chunks_total)
 450                 return -E_CHUNK;
 451         get_chunk(chunk_num, buf, len);
 452         return 1;
 453 }
 454
 455 /**
 456  * Main sending function.
 457  *
 458  * This function gets called from para_server as soon as the next chunk of data
 459  * should be pushed out. It obtains a pointer to the data to be sent out as
 460  * well as its length from mmd->afd.afhi. This information is then passed to
 461  * each supported sender's send() function which is supposed to send out the data
 462  * to all connected clients.
 463  */
 464 void vss_send_chunk(void)
 465 {
 466         int i;
 467         struct timeval now, due;
 468         char *buf;
 469         size_t len;
 470
 471         if (!map || !vss_playing())
 472                 return;
 473         gettimeofday(&now, NULL);
 474         vss_next_chunk_time(&due);
 475         if (tv_diff(&due, &now, NULL) > 0)
 476                 return;
 477         if (chk_barrier("eof", &now, &eof_barrier, &due, 1) < 0)
 478                 return;
 479         if (chk_barrier("data send", &now, &data_send_barrier,
 480                         &due, 1) < 0)
 481                 return;
 482         mmd->new_vss_status_flags &= ~VSS_REPOS;
 483         if (mmd->current_chunk >= mmd->afd.afhi.chunks_total) { /* eof */
 484                 mmd->new_vss_status_flags |= VSS_NEXT;
 485                 return vss_eof();
 486         }
 487         /*
 488          * We call the send function also in case of empty chunks as they
 489          * might have still some data queued which can be sent in this case.
 490          */
 491         if (!mmd->chunks_sent) {
 492                 struct timeval tmp;
 493                 gettimeofday(&mmd->stream_start, NULL);
 494                 tv_scale(mmd->current_chunk, &mmd->afd.afhi.chunk_tv, &tmp);
 495                 mmd->offset = tv2ms(&tmp);
 496                 mmd->events++;
 497         }
 498         get_chunk(mmd->current_chunk, &buf, &len);
 499         for (i = 0; senders[i].name; i++)
 500                 senders[i].send(mmd->current_chunk, mmd->chunks_sent, buf, len);
 501         mmd->new_vss_status_flags |= VSS_PLAYING;
 502         mmd->chunks_sent++;
 503         mmd->current_chunk++;
 504 }