vss.c

   1 /*
   2  * Copyright (C) 1997-2009 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 <dirent.h>
  15
  16 #include "para.h"
  17 #include "error.h"
  18 #include "string.h"
  19 #include "afh.h"
  20 #include "afs.h"
  21 #include "server.h"
  22 #include "net.h"
  23 #include "server.cmdline.h"
  24 #include "vss.h"
  25 #include "list.h"
  26 #include "send.h"
  27 #include "ipc.h"
  28 #include "fd.h"
  29 #include "sched.h"
  30
  31 extern struct misc_meta_data *mmd;
  32
  33 extern void dccp_send_init(struct sender *);
  34 extern void http_send_init(struct sender *);
  35 extern void udp_send_init(struct sender *);
  36
  37 /** The list of supported senders. */
  38 struct sender senders[] = {
  39         {
  40                 .name = "http",
  41                 .init = http_send_init,
  42         },
  43         {
  44                 .name = "dccp",
  45                 .init = dccp_send_init,
  46         },
  47         {
  48                 .name = "udp",
  49                 .init = udp_send_init,
  50         },
  51         {
  52                 .name = NULL,
  53         }
  54 };
  55
  56 /** The possible states of the afs socket. */
  57 enum afs_socket_status {
  58         /** Socket is inactive. */
  59         AFS_SOCKET_READY,
  60         /** Socket fd was included in the write fd set for select(). */
  61         AFS_SOCKET_CHECK_FOR_WRITE,
  62         /** vss wrote a request to the socket and waits for reply from afs. */
  63         AFS_SOCKET_AFD_PENDING
  64 };
  65
  66 /** The task structure for the virtual streaming system. */
  67 struct vss_task {
  68         /** Copied from the -announce_time command line option. */
  69         struct timeval announce_tv;
  70         /** End of the announcing interval. */
  71         struct timeval data_send_barrier;
  72         /** End of the EOF interval. */
  73         struct timeval eof_barrier;
  74         /** Only used if --autoplay_delay was given. */
  75         struct timeval autoplay_barrier;
  76         /** Used for afs-server communication. */
  77         int afs_socket;
  78         /** The current state of \a afs_socket. */
  79         enum afs_socket_status afsss;
  80         /** The memory mapped audio file. */
  81         char *map;
  82         /** Used by the scheduler. */
  83         struct task task;
  84         /** Pointer to the header of the mapped audio file. */
  85         const char *header_buf;
  86         /** Length of the audio file header. */
  87         size_t header_len;
  88 };
  89
  90 /**
  91  * Check if vss status flag \a P (playing) is set.
  92  *
  93  * \return Greater than zero if playing, zero otherwise.
  94  *
  95  */
  96 unsigned int vss_playing(void)
  97 {
  98         return mmd->new_vss_status_flags & VSS_PLAYING;
  99 }
 100
 101 /**
 102  * Check if the \a N (next) status flag is set.
 103  *
 104  * \return Greater than zero if set, zero if not.
 105  *
 106  */
 107 unsigned int vss_next(void)
 108 {
 109         return mmd->new_vss_status_flags & VSS_NEXT;
 110 }
 111
 112 /**
 113  * Check if a reposition request is pending.
 114  *
 115  * \return Greater than zero if true, zero otherwise.
 116  *
 117  */
 118 unsigned int vss_repos(void)
 119 {
 120         return mmd->new_vss_status_flags & VSS_REPOS;
 121 }
 122
 123 /**
 124  * Check if the vss is currently paused.
 125  *
 126  * \return Greater than zero if paused, zero otherwise.
 127  *
 128  */
 129 unsigned int vss_paused(void)
 130 {
 131         return !(mmd->new_vss_status_flags & VSS_NEXT)
 132                 && !(mmd->new_vss_status_flags & VSS_PLAYING);
 133 }
 134
 135 /**
 136  * Check if the vss is currently stopped.
 137  *
 138  * \return Greater than zero if paused, zero otherwise.
 139  *
 140  */
 141 unsigned int vss_stopped(void)
 142 {
 143         return (mmd->new_vss_status_flags & VSS_NEXT)
 144                 && !(mmd->new_vss_status_flags & VSS_PLAYING);
 145 }
 146
 147 static int chk_barrier(const char *bname, const struct timeval *barrier,
 148                 struct timeval *diff, int print_log)
 149 {
 150         long ms;
 151
 152         if (tv_diff(now, barrier, diff) > 0)
 153                 return 1;
 154         ms = tv2ms(diff);
 155         if (print_log && ms)
 156                 PARA_DEBUG_LOG("%s barrier: %lims left\n", bname, ms);
 157         return -1;
 158 }
 159
 160 /*
 161  * != NULL: timeout for next chunk
 162  * NULL: nothing to do
 163  */
 164 static struct timeval *vss_compute_timeout(struct vss_task *vsst)
 165 {
 166         static struct timeval the_timeout;
 167         struct timeval next_chunk;
 168
 169         if (vss_next() && vsst->map) {
 170                 /* only sleep a bit, nec*/
 171                 the_timeout.tv_sec = 0;
 172                 the_timeout.tv_usec = 100;
 173                 return &the_timeout;
 174         }
 175         if (chk_barrier("autoplay_delay", &vsst->autoplay_barrier,
 176                         &the_timeout, 1) < 0)
 177                 return &the_timeout;
 178         if (chk_barrier("eof", &vsst->eof_barrier, &the_timeout, 1) < 0)
 179                 return &the_timeout;
 180         if (chk_barrier("data send", &vsst->data_send_barrier,
 181                         &the_timeout, 1) < 0)
 182                 return &the_timeout;
 183         if (!vss_playing() || !vsst->map)
 184                 return NULL;
 185         compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
 186                 &mmd->stream_start, &next_chunk);
 187         if (chk_barrier("chunk", &next_chunk, &the_timeout, 0) < 0)
 188                 return &the_timeout;
 189         /* chunk is due or bof */
 190         the_timeout.tv_sec = 0;
 191         the_timeout.tv_usec = 0;
 192         return &the_timeout;
 193 }
 194
 195 static void vss_eof(struct vss_task *vsst)
 196 {
 197         mmd->stream_start = *now;
 198         if (!vsst->map)
 199                 return;
 200         if (mmd->new_vss_status_flags & VSS_NOMORE)
 201                 mmd->new_vss_status_flags = VSS_NEXT;
 202         tv_add(&mmd->afd.afhi.eof_tv, now, &vsst->eof_barrier);
 203         para_munmap(vsst->map, mmd->size);
 204         vsst->map = NULL;
 205         mmd->chunks_sent = 0;
 206         mmd->offset = 0;
 207         mmd->afd.afhi.seconds_total = 0;
 208         mmd->afd.afhi.chunk_tv.tv_sec = 0;
 209         mmd->afd.afhi.chunk_tv.tv_usec = 0;
 210         free(mmd->afd.afhi.chunk_table);
 211         mmd->afd.afhi.chunk_table = NULL;
 212         free(mmd->afd.afhi.info_string);
 213         mmd->afd.afhi.info_string = make_message("%s:\n%s:\n%s:\n", status_item_list[SI_AUDIO_FILE_INFO],
 214                 status_item_list[SI_TAGINFO1], status_item_list[SI_TAGINFO2]);
 215         make_empty_status_items(mmd->afd.verbose_ls_output);
 216         mmd->mtime = 0;
 217         mmd->size = 0;
 218         mmd->events++;
 219 }
 220
 221 /**
 222  * Get the list of all supported audio formats.
 223  *
 224  * \return Aa space separated list of all supported audio formats
 225  * It is not allocated at runtime, i.e. there is no need to free
 226  * the returned string in the caller.
 227  */
 228 const char *supported_audio_formats(void)
 229 {
 230         return SUPPORTED_AUDIO_FORMATS;
 231 }
 232
 233 /**
 234  * Get the chunk time of the current audio file.
 235  *
 236  * \return A pointer to a struct containing the chunk time, or NULL,
 237  * if currently no audio file is selected.
 238  */
 239 struct timeval *vss_chunk_time(void)
 240 {
 241         if (mmd->afd.afhi.chunk_tv.tv_sec == 0 &&
 242                         mmd->afd.afhi.chunk_tv.tv_usec == 0)
 243                 return NULL;
 244         return &mmd->afd.afhi.chunk_tv;
 245 }
 246
 247 static int need_to_request_new_audio_file(struct vss_task *vsst)
 248 {
 249         struct timeval diff;
 250
 251         if (vsst->map) /* have audio file */
 252                 return 0;
 253         if (!vss_playing()) /* don't need one */
 254                 return 0;
 255         if (mmd->new_vss_status_flags & VSS_NOMORE)
 256                 return 0;
 257         if (vsst->afsss == AFS_SOCKET_AFD_PENDING) /* already requested one */
 258                 return 0;
 259         if (chk_barrier("autoplay_delay", &vsst->autoplay_barrier,
 260                         &diff, 1) < 0)
 261                 return 0;
 262         return 1;
 263 }
 264
 265 /**
 266  * Compute the timeout for para_server's main select-loop.
 267  *
 268  * This function gets called from para_server to determine the timeout value
 269  * for its main select loop.
 270  *
 271  * \param s Pointer to the server scheduler.
 272  * \param t Pointer to the vss task structure.
 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 static void vss_pre_select(struct sched *s, struct task *t)
 283 {
 284         int i;
 285         struct timeval *tv, diff;
 286         struct vss_task *vsst = container_of(t, struct vss_task, task);
 287
 288         if (!vsst->map || vss_next() || vss_paused() || vss_repos())
 289                 for (i = 0; senders[i].name; i++)
 290                         senders[i].shutdown_clients();
 291         if (vss_next())
 292                 vss_eof(vsst);
 293         else if (vss_paused()) {
 294                 if (mmd->chunks_sent)
 295                         tv_add(&mmd->afd.afhi.eof_tv, now, &vsst->eof_barrier);
 296                 mmd->chunks_sent = 0;
 297         } else if (vss_repos()) {
 298                 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
 299                 tv_add(&mmd->afd.afhi.eof_tv, now, &vsst->eof_barrier);
 300                 mmd->chunks_sent = 0;
 301                 mmd->current_chunk = mmd->repos_request;
 302                 mmd->new_vss_status_flags &= ~VSS_REPOS;
 303         }
 304         if (need_to_request_new_audio_file(vsst)) {
 305                 PARA_DEBUG_LOG("ready and playing, but no audio file\n");
 306                 para_fd_set(vsst->afs_socket, &s->wfds, &s->max_fileno);
 307                 vsst->afsss = AFS_SOCKET_CHECK_FOR_WRITE;
 308         } else
 309                 para_fd_set(vsst->afs_socket, &s->rfds, &s->max_fileno);
 310         for (i = 0; senders[i].name; i++) {
 311                 if (!senders[i].pre_select)
 312                         continue;
 313                 senders[i].pre_select(&s->max_fileno, &s->rfds, &s->wfds);
 314         }
 315         tv = vss_compute_timeout(vsst);
 316         if (tv && tv_diff(tv, &s->timeout, &diff) < 0)
 317                 s->timeout = *tv;
 318 }
 319
 320 static int recv_afs_msg(int afs_socket, int *fd, uint32_t *code, uint32_t *data)
 321 {
 322         char control[255], buf[8];
 323         struct msghdr msg = {.msg_iov = NULL};
 324         struct cmsghdr *cmsg;
 325         struct iovec iov;
 326         int ret = 0;
 327
 328         *fd = -1;
 329         iov.iov_base = buf;
 330         iov.iov_len = sizeof(buf);
 331         msg.msg_iov = &iov;
 332         msg.msg_iovlen = 1;
 333         msg.msg_control = control;
 334         msg.msg_controllen = sizeof(control);
 335         memset(buf, 0, sizeof(buf));
 336         ret = recvmsg(afs_socket, &msg, 0);
 337         if (ret < 0)
 338                 return -ERRNO_TO_PARA_ERROR(errno);
 339         if (iov.iov_len != sizeof(buf))
 340                 return -E_AFS_SHORT_READ;
 341         *code = *(uint32_t*)buf;
 342         *data =  *(uint32_t*)(buf + 4);
 343         for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
 344                 if (cmsg->cmsg_level != SOL_SOCKET
 345                         || cmsg->cmsg_type != SCM_RIGHTS)
 346                 continue;
 347                 if ((cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int) != 1)
 348                 continue;
 349                 *fd = *(int *)CMSG_DATA(cmsg);
 350         }
 351         return 1;
 352 }
 353
 354 static void recv_afs_result(struct vss_task *vsst)
 355 {
 356         int ret, passed_fd, shmid;
 357         uint32_t afs_code = 0, afs_data = 0;
 358         struct stat statbuf;
 359
 360         vsst->afsss = AFS_SOCKET_READY;
 361         mmd->afd.afhi.chunk_table = NULL;
 362         ret = recv_afs_msg(vsst->afs_socket, &passed_fd, &afs_code, &afs_data);
 363         if (ret < 0)
 364                 goto err;
 365         PARA_DEBUG_LOG("fd: %d, code: %u, shmid: %u\n", passed_fd, afs_code,
 366                 afs_data);
 367         ret = -E_NOFD;
 368         if (afs_code != NEXT_AUDIO_FILE)
 369                 goto err;
 370         if (passed_fd < 0)
 371                 goto err;
 372         shmid = afs_data;
 373         ret = load_afd(shmid, &mmd->afd);
 374         if (ret < 0)
 375                 goto err;
 376         shm_destroy(shmid);
 377         ret = fstat(passed_fd, &statbuf);
 378         if (ret < 0) {
 379                 PARA_ERROR_LOG("fstat error:\n");
 380                 ret = -ERRNO_TO_PARA_ERROR(errno);
 381                 goto err;
 382         }
 383         mmd->size = statbuf.st_size;
 384         mmd->mtime = statbuf.st_mtime;
 385         ret = para_mmap(mmd->size, PROT_READ, MAP_PRIVATE, passed_fd,
 386                 0, &vsst->map);
 387         if (ret < 0)
 388                 goto err;
 389         close(passed_fd);
 390         mmd->chunks_sent = 0;
 391         mmd->current_chunk = 0;
 392         mmd->offset = 0;
 393         mmd->events++;
 394         mmd->num_played++;
 395         mmd->new_vss_status_flags &= (~VSS_NEXT);
 396         afh_get_header(&mmd->afd.afhi, vsst->map, &vsst->header_buf,
 397                 &vsst->header_len);
 398         return;
 399 err:
 400         free(mmd->afd.afhi.chunk_table);
 401         if (passed_fd >= 0)
 402                 close(passed_fd);
 403         PARA_ERROR_LOG("%s\n", para_strerror(-ret));
 404         mmd->new_vss_status_flags = VSS_NEXT;
 405 }
 406
 407 /**
 408  * Main sending function.
 409  *
 410  * This function gets called from para_server as soon as the next chunk of data
 411  * should be pushed out. It obtains a pointer to the data to be sent out as
 412  * well as its length from mmd->afd.afhi. This information is then passed to
 413  * each supported sender's send() function which is supposed to send out the data
 414  * to all connected clients.
 415  */
 416 static void vss_send_chunk(struct vss_task *vsst)
 417 {
 418         int i;
 419         struct timeval due;
 420         const char *buf;
 421         size_t len;
 422
 423         if (!vsst->map || !vss_playing())
 424                 return;
 425         compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
 426                 &mmd->stream_start, &due);
 427         if (tv_diff(&due, now, NULL) > 0)
 428                 return;
 429         if (chk_barrier("eof", &vsst->eof_barrier, &due, 1) < 0)
 430                 return;
 431         if (chk_barrier("data send", &vsst->data_send_barrier,
 432                         &due, 1) < 0)
 433                 return;
 434         if (mmd->current_chunk >= mmd->afd.afhi.chunks_total) { /* eof */
 435                 mmd->new_vss_status_flags |= VSS_NEXT;
 436                 return;
 437         }
 438         /*
 439          * We call the send function also in case of empty chunks as they
 440          * might have still some data queued which can be sent in this case.
 441          */
 442         if (!mmd->chunks_sent) {
 443                 struct timeval tmp;
 444                 mmd->stream_start = *now;
 445                 tv_scale(mmd->current_chunk, &mmd->afd.afhi.chunk_tv, &tmp);
 446                 mmd->offset = tv2ms(&tmp);
 447                 mmd->events++;
 448         }
 449         afh_get_chunk(mmd->current_chunk, &mmd->afd.afhi, vsst->map, &buf, &len);
 450         for (i = 0; senders[i].name; i++)
 451                 senders[i].send(mmd->current_chunk, mmd->chunks_sent, buf, len,
 452                         vsst->header_buf, vsst->header_len);
 453         mmd->new_vss_status_flags |= VSS_PLAYING;
 454         mmd->chunks_sent++;
 455         mmd->current_chunk++;
 456 }
 457
 458 static void vss_post_select(struct sched *s, struct task *t)
 459 {
 460         int ret, i;
 461         struct vss_task *vsst = container_of(t, struct vss_task, task);
 462
 463         if (mmd->sender_cmd_data.cmd_num >= 0) {
 464                 int num = mmd->sender_cmd_data.cmd_num,
 465                         sender_num = mmd->sender_cmd_data.sender_num;
 466
 467                 if (senders[sender_num].client_cmds[num])
 468                         senders[sender_num].client_cmds[num](&mmd->sender_cmd_data);
 469                 mmd->sender_cmd_data.cmd_num = -1;
 470         }
 471         if (vsst->afsss != AFS_SOCKET_CHECK_FOR_WRITE) {
 472                 if (FD_ISSET(vsst->afs_socket, &s->rfds))
 473                         recv_afs_result(vsst);
 474         } else if (FD_ISSET(vsst->afs_socket, &s->wfds)) {
 475                 PARA_NOTICE_LOG("requesting new fd from afs\n");
 476                 ret = send_buffer(vsst->afs_socket, "new");
 477                 vsst->afsss = AFS_SOCKET_AFD_PENDING;
 478         }
 479         for (i = 0; senders[i].name; i++) {
 480                 if (!senders[i].post_select)
 481                         continue;
 482                 senders[i].post_select(&s->rfds, &s->wfds);
 483         }
 484         if ((vss_playing() && !(mmd->vss_status_flags & VSS_PLAYING)) ||
 485                         (vss_next() && vss_playing()))
 486                 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
 487         vss_send_chunk(vsst);
 488 }
 489
 490 /**
 491  * Initialize the virtual streaming system task.
 492  *
 493  * \param afs_socket The fd for communication with afs.
 494  *
 495  * This also initializes all supported senders and starts streaming
 496  * if the --autoplay command line flag was given.
 497  */
 498 void init_vss_task(int afs_socket)
 499 {
 500         static struct vss_task vss_task_struct, *vsst = &vss_task_struct;
 501         int i;
 502         char *hn = para_hostname(), *home = para_homedir();
 503         long unsigned announce_time = conf.announce_time_arg > 0?
 504                         conf.announce_time_arg : 300,
 505                 autoplay_delay = conf.autoplay_delay_arg > 0?
 506                         conf.autoplay_delay_arg : 0;
 507
 508         vsst->afs_socket = afs_socket;
 509         vsst->task.pre_select = vss_pre_select;
 510         vsst->task.post_select = vss_post_select;
 511         ms2tv(announce_time, &vsst->announce_tv);
 512         PARA_INFO_LOG("announce timeval: %lums\n", tv2ms(&vsst->announce_tv));
 513         for (i = 0; senders[i].name; i++) {
 514                 PARA_NOTICE_LOG("initializing %s sender\n", senders[i].name);
 515                 senders[i].init(&senders[i]);
 516         }
 517         free(hn);
 518         free(home);
 519         mmd->sender_cmd_data.cmd_num = -1;
 520         make_empty_status_items(mmd->afd.verbose_ls_output);
 521         if (conf.autoplay_given) {
 522                 struct timeval tmp;
 523                 mmd->vss_status_flags |= VSS_PLAYING;
 524                 mmd->new_vss_status_flags |= VSS_PLAYING;
 525                 ms2tv(autoplay_delay, &tmp);
 526                 tv_add(now, &tmp, &vsst->autoplay_barrier);
 527                 tv_add(&vsst->autoplay_barrier, &vsst->announce_tv,
 528                         &vsst->data_send_barrier);
 529         }
 530         register_task(&vsst->task);
 531 }