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 \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  * Call the init functions of all supported audio format handlers and
  93  * initialize all supported senders.
  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->afi.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() && mmd->audio_format >= 0) {
 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 (mmd->audio_format < 0 || !vss_playing() || !map)
 168                 return NULL;
 169         vss_next_chunk_time(&next_chunk);
 170         if (chk_barrier(audio_format_name(mmd->audio_format), &now, &next_chunk,
 171                         &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         PARA_NOTICE_LOG("EOF\n");
 186         if (!map) {
 187                 for (i = 0; senders[i].name; i++)
 188                         senders[i].shutdown_clients();
 189                 return;
 190         }
 191         gettimeofday(&now, NULL);
 192         tv_add(&mmd->afi.eof_tv, &now, &eof_barrier);
 193         munmap(map, mmd->size);
 194         map = NULL;
 195         mmd->audio_format = -1;
 196         mmd->chunks_sent = 0;
 197         mmd->offset = 0;
 198         mmd->afi.seconds_total = 0;
 199         free(mmd->afi.chunk_table);
 200         mmd->afi.chunk_table = NULL;
 201         tmp  = make_message("%s:\n%s:\n%s:\n", status_item_list[SI_AUDIO_INFO1],
 202                 status_item_list[SI_AUDIO_INFO2], status_item_list[SI_AUDIO_INFO3]);
 203         strcpy(mmd->afi.info_string, tmp);
 204         free(tmp);
 205         mmd->filename[0] = '\0';
 206         mmd->size = 0;
 207         mmd->events++;
 208 }
 209
 210 /**
 211  * Get the header of the current audio file.
 212  *
 213  * \param header_len the length of the header is stored here
 214  *
 215  * \return a pointer to a buffer containing the header, or NULL, if no audio
 216  * file is selected or if the current audio format does not need special header
 217  * treamtment.
 218  *
 219  */
 220 char *vss_get_header(size_t *header_len)
 221 {
 222         if (mmd->audio_format < 0 || !map || !mmd->afi.header_len)
 223                 return NULL;
 224         *header_len = mmd->afi.header_len;
 225         return map + mmd->afi.header_offset;
 226 }
 227
 228 /**
 229  * get the list of all supported audio formats
 230  *
 231  * \return a space separated list of all supported audio formats
 232  * It is not allocated at runtime, i.e. there is no need to free
 233  * the returned string in the caller.
 234  */
 235 const char *supported_audio_formats(void)
 236 {
 237         return SUPPORTED_AUDIO_FORMATS;
 238 }
 239
 240 /**
 241  * get the chunk time of the current audio file
 242  *
 243  * \return a pointer to a struct containing the chunk time, or NULL,
 244  * if currently no audio file is selected.
 245  */
 246 struct timeval *vss_chunk_time(void)
 247 {
 248         if (mmd->audio_format < 0)
 249                 return NULL;
 250         return &mmd->afi.chunk_tv;
 251 }
 252
 253 enum afs_socket_status {
 254         AFS_SOCKET_READY,
 255         AFS_SOCKET_CHECK_FOR_WRITE,
 256         AFS_SOCKET_AFD_PENDING
 257 };
 258
 259 static enum afs_socket_status afsss;
 260
 261 /**
 262  * Compute the timeout for para_server's main select-loop.
 263  *
 264  * This function gets called from para_server to determine the timeout value
 265  * for its main select loop.
 266  *
 267  * Before the timeout is computed, the current vss status flags are evaluated
 268  * and acted upon by calling appropriate functions from the lower layers.
 269  * Possible actions include
 270  *
 271  *      - request a new audio file from afs,
 272  *      - shutdown of all senders (stop/pause command),
 273  *      - reposition the stream (ff/jmp command).
 274  *
 275  * \return A pointer to a struct timeval containing the timeout for the next
 276  * chunk of data to be sent, or NULL if we're not sending right now.
 277  */
 278 struct timeval *vss_preselect(fd_set *rfds, fd_set *wfds, int *max_fileno)
 279 {
 280         int i;
 281         struct timeval *tv;
 282
 283         para_fd_set(afs_socket, rfds, max_fileno);
 284         if (!map)
 285                 for (i = 0; senders[i].name; i++)
 286                         senders[i].shutdown_clients();
 287         else {
 288                 if (vss_next()) {
 289                         vss_eof();
 290                         return vss_compute_timeout();
 291                 }
 292         }
 293         if (vss_paused() || vss_repos()) {
 294                 for (i = 0; senders[i].name; i++)
 295                         senders[i].shutdown_clients();
 296                 if (map) {
 297                         struct timeval now;
 298                         gettimeofday(&now, NULL);
 299                         if (!vss_paused() || mmd->chunks_sent)
 300                                 tv_add(&mmd->afi.eof_tv, &now, &eof_barrier);
 301                         if (vss_repos())
 302                                 tv_add(&now, &announce_tv, &data_send_barrier);
 303                         if (mmd->new_vss_status_flags & VSS_NOMORE)
 304                                 mmd->new_vss_status_flags = VSS_NEXT;
 305                 }
 306                 mmd->chunks_sent = 0;
 307         }
 308         if (vss_repos()) {
 309                 mmd->new_vss_status_flags &= ~(VSS_REPOS);
 310                 mmd->current_chunk = mmd->repos_request;
 311         }
 312         tv = vss_compute_timeout();
 313         if (tv)
 314                 return tv;
 315         if (!map && vss_playing() &&
 316                         !(mmd->new_vss_status_flags & VSS_NOMORE)) {
 317                 PARA_DEBUG_LOG("%s", "ready and playing, but no audio file\n");
 318                 if (afsss == AFS_SOCKET_READY) {
 319                         para_fd_set(afs_socket, wfds, max_fileno);
 320                         afsss = AFS_SOCKET_CHECK_FOR_WRITE;
 321                 }
 322         }
 323         return tv;
 324 }
 325
 326 static int recv_afs_msg(int *fd, uint32_t *code, uint32_t *data)
 327 {
 328         char control[255], buf[8];
 329         struct msghdr msg = {.msg_iov = NULL};
 330         struct cmsghdr *cmsg;
 331         struct iovec iov;
 332         int ret = 0;
 333
 334         iov.iov_base = buf;
 335         iov.iov_len = sizeof(buf);
 336         msg.msg_iov = &iov;
 337         msg.msg_iovlen = 1;
 338         msg.msg_control = control;
 339         msg.msg_controllen = sizeof(control);
 340         memset(buf, 0, sizeof(buf));
 341         ret = recvmsg(afs_socket, &msg, 0);
 342         if (ret < 0)
 343                 return -ERRNO_TO_PARA_ERROR(errno);
 344         if (iov.iov_len != sizeof(buf))
 345                 return -E_SHORT_AFS_READ;
 346         *code = *(uint32_t*)buf;
 347         *data =  *(uint32_t*)(buf + 4);
 348         cmsg = CMSG_FIRSTHDR(&msg);
 349         for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
 350                 if (cmsg->cmsg_level != SOL_SOCKET
 351                         || cmsg->cmsg_type != SCM_RIGHTS)
 352                 continue;
 353                 if ((cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int) != 1)
 354                 continue;
 355                 *fd = *(int *)CMSG_DATA(cmsg);
 356         }
 357         return 1;
 358 }
 359
 360 static void recv_afs_result(void)
 361 {
 362         int ret, passed_fd = -1, shmid;
 363         uint32_t afs_code = 0, afs_data = 0;
 364         struct stat statbuf;
 365         struct timeval now;
 366
 367         PARA_NOTICE_LOG("recv\n");
 368         ret = recv_afs_msg(&passed_fd, &afs_code, &afs_data);
 369         if (ret < 0)
 370                 goto err;
 371         PARA_NOTICE_LOG("got the fd: %d, code: %u, shmid: %u\n",
 372                 passed_fd, afs_code, afs_data);
 373         ret = -E_BAD_AFS_CODE;
 374         if (afs_code != NEXT_AUDIO_FILE)
 375                 goto err;
 376         afsss = AFS_SOCKET_READY;
 377         shmid = afs_data;
 378         ret = load_afd(shmid, &mmd->afd);
 379         if (ret < 0)
 380                 goto err;
 381         shm_destroy(shmid);
 382         PARA_NOTICE_LOG("next audio file: %s (%lu chunks)\n", mmd->afd.path,
 383                 mmd->afd.afhi.chunks_total);
 384         ret = fstat(passed_fd, &statbuf);
 385         if (ret < 0) {
 386                 PARA_ERROR_LOG("fstat error:\n");
 387                 ret = -ERRNO_TO_PARA_ERROR(errno);
 388                 goto err;
 389         }
 390         mmd->size = statbuf.st_size;
 391         mmd->mtime = statbuf.st_mtime;
 392         map = para_mmap(mmd->size, PROT_READ, MAP_PRIVATE,
 393                 passed_fd, 0);
 394         close(passed_fd);
 395         strcpy(mmd->filename, mmd->afd.path); /* FIXME: check length */
 396         mmd->afi.header_len = 0; /* default: no header */
 397         mmd->audio_format = mmd->afd.afsi.audio_format_id;
 398         mmd->chunks_sent = 0;
 399         mmd->current_chunk = 0;
 400         mmd->offset = 0;
 401         mmd->events++;
 402         mmd->num_played++;
 403         mmd->afi = mmd->afd.afhi;
 404         mmd->new_vss_status_flags &= (~VSS_NEXT);
 405         gettimeofday(&now, NULL);
 406         tv_add(&now, &announce_tv, &data_send_barrier);
 407         return;
 408 err:
 409         if (passed_fd >= 0)
 410                 close(passed_fd);
 411         PARA_ERROR_LOG("%s\n", PARA_STRERROR(-ret));
 412 }
 413
 414 void vss_post_select(fd_set *rfds, fd_set *wfds)
 415 {
 416         int ret;
 417
 418         if (FD_ISSET(afs_socket, rfds))
 419                 recv_afs_result();
 420         if (afsss != AFS_SOCKET_CHECK_FOR_WRITE || !FD_ISSET(afs_socket, wfds))
 421                 return;
 422         PARA_NOTICE_LOG("requesting new socket\n");
 423         ret = send_buffer(afs_socket, "new");
 424         afsss = AFS_SOCKET_AFD_PENDING;
 425 }
 426
 427 static void get_chunk(long unsigned chunk_num, char **buf, size_t *len)
 428 {
 429         size_t pos = mmd->afi.chunk_table[chunk_num];
 430         *buf = map + pos;
 431         *len = mmd->afi.chunk_table[chunk_num + 1] - pos;
 432
 433         if (chunk_num + 5 > mmd->afd.afhi.chunks_total)
 434                 PARA_NOTICE_LOG("chunk %lu/%lu\n, len: %zu\n", chunk_num,
 435                         mmd->afd.afhi.chunks_total, *len);
 436 }
 437
 438 /**
 439  * Get the data of the given chunk.
 440  *
 441  * \param chunk_num The number of the desired chunk.
 442  * \param buf Chunk data.
 443  * \param len Chunk length in bytes.
 444  *
 445  * \return Positive on success, negative on errors.
 446  */
 447 int vss_get_chunk(long unsigned chunk_num, char **buf, size_t *len)
 448 {
 449         if (mmd->audio_format < 0 || !map || !vss_playing())
 450                 return -E_CHUNK;
 451         if (chunk_num >= mmd->afi.chunks_total)
 452                 return -E_CHUNK;
 453         get_chunk(chunk_num, buf, len);
 454         return 1;
 455 }
 456
 457 /**
 458  * main sending function
 459  *
 460  * This function gets called from para_server as soon as the next chunk of
 461  * data should be pushed out. It first calls the read_chunk() function of
 462  * the current audio format handler to obtain a pointer to the data to be
 463  * sent out as well as its length. This information is then passed to each
 464  * supported sender's send() function which does the actual sending.
 465  */
 466 void vss_send_chunk(void)
 467 {
 468         int i;
 469         struct timeval now, due;
 470         char *buf;
 471         size_t len;
 472
 473         if (mmd->audio_format < 0 || !map || !vss_playing())
 474                 return;
 475         gettimeofday(&now, NULL);
 476         vss_next_chunk_time(&due);
 477         if (tv_diff(&due, &now, NULL) > 0)
 478                 return;
 479         if (chk_barrier("eof", &now, &eof_barrier, &due, 1) < 0)
 480                 return;
 481         if (chk_barrier("data send", &now, &data_send_barrier,
 482                         &due, 1) < 0)
 483                 return;
 484         mmd->new_vss_status_flags &= ~VSS_REPOS;
 485         if (mmd->current_chunk >= mmd->afi.chunks_total) { /* eof */
 486                 mmd->new_vss_status_flags |= VSS_NEXT;
 487                 return vss_eof();
 488         }
 489         /*
 490          * We call the send function also in case of empty chunks as they
 491          * might have still some data queued which can be sent in this case.
 492          */
 493         if (!mmd->chunks_sent) {
 494                 struct timeval tmp;
 495                 gettimeofday(&mmd->stream_start, NULL);
 496                 tv_scale(mmd->current_chunk, &mmd->afi.chunk_tv, &tmp);
 497                 mmd->offset = tv2ms(&tmp);
 498                 mmd->events++;
 499         }
 500         get_chunk(mmd->current_chunk, &buf, &len);
 501         for (i = 0; senders[i].name; i++)
 502                 senders[i].send(mmd->current_chunk, mmd->chunks_sent, buf, len);
 503         mmd->new_vss_status_flags |= VSS_PLAYING;
 504         mmd->chunks_sent++;
 505         mmd->current_chunk++;
 506 }