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 <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 ortp_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 #ifdef HAVE_ORTP
  48         {
  49                 .name = "ortp",
  50                 .init = ortp_send_init,
  51         },
  52 #endif
  53         {
  54                 .name = NULL,
  55         }
  56 };
  57
  58 /** The possible states of the afs socket. */
  59 enum afs_socket_status {
  60         /** Socket is inactive. */
  61         AFS_SOCKET_READY,
  62         /** Socket fd was included in the write fd set for select(). */
  63         AFS_SOCKET_CHECK_FOR_WRITE,
  64         /** vss wrote a request to the socket and waits for reply from afs. */
  65         AFS_SOCKET_AFD_PENDING
  66 };
  67
  68 /** The task structure for the virtual streaming system. */
  69 struct vss_task {
  70         struct timeval announce_tv;
  71         struct timeval data_send_barrier;
  72         struct timeval eof_barrier;
  73         struct timeval autoplay_barrier;
  74         int afs_socket;
  75         enum afs_socket_status afsss;
  76         char *map;
  77         struct task task;
  78         const char *header_buf;
  79         size_t header_len;
  80 };
  81
  82 /**
  83  * Check if vss status flag \a P (playing) is set.
  84  *
  85  * \return Greater than zero if playing, zero otherwise.
  86  *
  87  */
  88 unsigned int vss_playing(void)
  89 {
  90         return mmd->new_vss_status_flags & VSS_PLAYING;
  91 }
  92
  93 /**
  94  * Check if the \a N (next) status flag is set.
  95  *
  96  * \return Greater than zero if set, zero if not.
  97  *
  98  */
  99 unsigned int vss_next(void)
 100 {
 101         return mmd->new_vss_status_flags & VSS_NEXT;
 102 }
 103
 104 /**
 105  * Check if a reposition request is pending.
 106  *
 107  * \return Greater than zero if true, zero otherwise.
 108  *
 109  */
 110 unsigned int vss_repos(void)
 111 {
 112         return mmd->new_vss_status_flags & VSS_REPOS;
 113 }
 114
 115 /**
 116  * Check if the vss is currently paused.
 117  *
 118  * \return Greater than zero if paused, zero otherwise.
 119  *
 120  */
 121 unsigned int vss_paused(void)
 122 {
 123         return !(mmd->new_vss_status_flags & VSS_NEXT)
 124                 && !(mmd->new_vss_status_flags & VSS_PLAYING);
 125 }
 126
 127 /**
 128  * Check if the vss is currently stopped.
 129  *
 130  * \return Greater than zero if paused, zero otherwise.
 131  *
 132  */
 133 unsigned int vss_stopped(void)
 134 {
 135         return (mmd->new_vss_status_flags & VSS_NEXT)
 136                 && !(mmd->new_vss_status_flags & VSS_PLAYING);
 137 }
 138
 139 static int chk_barrier(const char *bname, const struct timeval *barrier,
 140                 struct timeval *diff, int print_log)
 141 {
 142         long ms;
 143
 144         if (tv_diff(now, barrier, diff) > 0)
 145                 return 1;
 146         ms = tv2ms(diff);
 147         if (print_log && ms)
 148                 PARA_DEBUG_LOG("%s barrier: %lims left\n", bname, ms);
 149         return -1;
 150 }
 151
 152 /*
 153  * != NULL: timeout for next chunk
 154  * NULL: nothing to do
 155  */
 156 static struct timeval *vss_compute_timeout(struct vss_task *vsst)
 157 {
 158         static struct timeval the_timeout;
 159         struct timeval next_chunk;
 160
 161         if (vss_next() && vsst->map) {
 162                 /* only sleep a bit, nec*/
 163                 the_timeout.tv_sec = 0;
 164                 the_timeout.tv_usec = 100;
 165                 return &the_timeout;
 166         }
 167         if (chk_barrier("autoplay_delay", &vsst->autoplay_barrier,
 168                         &the_timeout, 1) < 0)
 169                 return &the_timeout;
 170         if (chk_barrier("eof", &vsst->eof_barrier, &the_timeout, 1) < 0)
 171                 return &the_timeout;
 172         if (chk_barrier("data send", &vsst->data_send_barrier,
 173                         &the_timeout, 1) < 0)
 174                 return &the_timeout;
 175         if (!vss_playing() || !vsst->map)
 176                 return NULL;
 177         compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
 178                 &mmd->stream_start, &next_chunk);
 179         if (chk_barrier("chunk", &next_chunk, &the_timeout, 0) < 0)
 180                 return &the_timeout;
 181         /* chunk is due or bof */
 182         the_timeout.tv_sec = 0;
 183         the_timeout.tv_usec = 0;
 184         return &the_timeout;
 185 }
 186
 187 static void vss_eof(struct vss_task *vsst)
 188 {
 189         mmd->stream_start = *now;
 190         if (!vsst->map)
 191                 return;
 192         if (mmd->new_vss_status_flags & VSS_NOMORE)
 193                 mmd->new_vss_status_flags = VSS_NEXT;
 194         tv_add(&mmd->afd.afhi.eof_tv, now, &vsst->eof_barrier);
 195         para_munmap(vsst->map, mmd->size);
 196         vsst->map = NULL;
 197         mmd->chunks_sent = 0;
 198         mmd->offset = 0;
 199         mmd->afd.afhi.seconds_total = 0;
 200         mmd->afd.afhi.chunk_tv.tv_sec = 0;
 201         mmd->afd.afhi.chunk_tv.tv_usec = 0;
 202         free(mmd->afd.afhi.chunk_table);
 203         mmd->afd.afhi.chunk_table = NULL;
 204         free(mmd->afd.afhi.info_string);
 205         mmd->afd.afhi.info_string = make_message("%s:\n%s:\n%s:\n", status_item_list[SI_AUDIO_FILE_INFO],
 206                 status_item_list[SI_TAGINFO1], status_item_list[SI_TAGINFO2]);
 207         make_empty_status_items(mmd->afd.verbose_ls_output);
 208         mmd->mtime = 0;
 209         mmd->size = 0;
 210         mmd->events++;
 211 }
 212
 213 /**
 214  * Get the list of all supported audio formats.
 215  *
 216  * \return Aa space separated list of all supported audio formats
 217  * It is not allocated at runtime, i.e. there is no need to free
 218  * the returned string in the caller.
 219  */
 220 const char *supported_audio_formats(void)
 221 {
 222         return SUPPORTED_AUDIO_FORMATS;
 223 }
 224
 225 /**
 226  * Get the chunk time of the current audio file.
 227  *
 228  * \return A pointer to a struct containing the chunk time, or NULL,
 229  * if currently no audio file is selected.
 230  */
 231 struct timeval *vss_chunk_time(void)
 232 {
 233         if (mmd->afd.afhi.chunk_tv.tv_sec == 0 &&
 234                         mmd->afd.afhi.chunk_tv.tv_usec == 0)
 235                 return NULL;
 236         return &mmd->afd.afhi.chunk_tv;
 237 }
 238
 239 static int need_to_request_new_audio_file(struct vss_task *vsst)
 240 {
 241         if (vsst->map) /* have audio file */
 242                 return 0;
 243         if (!vss_playing()) /* don't need one */
 244                 return 0;
 245         if (mmd->new_vss_status_flags & VSS_NOMORE)
 246                 return 0;
 247         if (vsst->afsss == AFS_SOCKET_AFD_PENDING) /* already requested one */
 248                 return 0;
 249         return 1;
 250 }
 251
 252 /**
 253  * Compute the timeout for para_server's main select-loop.
 254  *
 255  * This function gets called from para_server to determine the timeout value
 256  * for its main select loop.
 257  *
 258  * \param s Pointer to the server scheduler.
 259  * \param t Pointer to the vss task structure.
 260  *
 261  * Before the timeout is computed, the current vss status flags are evaluated
 262  * and acted upon by calling appropriate functions from the lower layers.
 263  * Possible actions include
 264  *
 265  *      - request a new audio file from afs,
 266  *      - shutdown of all senders (stop/pause command),
 267  *      - reposition the stream (ff/jmp command).
 268  */
 269 static void vss_pre_select(struct sched *s, struct task *t)
 270 {
 271         int i;
 272         struct timeval *tv, diff;
 273         struct vss_task *vsst = container_of(t, struct vss_task, task);
 274
 275         if (!vsst->map || vss_next() || vss_paused() || vss_repos())
 276                 for (i = 0; senders[i].name; i++)
 277                         senders[i].shutdown_clients();
 278         if (vss_next())
 279                 vss_eof(vsst);
 280         else if (vss_paused()) {
 281                 if (mmd->chunks_sent)
 282                         tv_add(&mmd->afd.afhi.eof_tv, now, &vsst->eof_barrier);
 283                 mmd->chunks_sent = 0;
 284         } else if (vss_repos()) {
 285                 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
 286                 tv_add(&mmd->afd.afhi.eof_tv, now, &vsst->eof_barrier);
 287                 mmd->chunks_sent = 0;
 288                 mmd->current_chunk = mmd->repos_request;
 289                 mmd->new_vss_status_flags &= ~VSS_REPOS;
 290         }
 291
 292         if (need_to_request_new_audio_file(vsst)) {
 293                 PARA_DEBUG_LOG("ready and playing, but no audio file\n");
 294                 para_fd_set(vsst->afs_socket, &s->wfds, &s->max_fileno);
 295                 vsst->afsss = AFS_SOCKET_CHECK_FOR_WRITE;
 296         } else
 297                 para_fd_set(vsst->afs_socket, &s->rfds, &s->max_fileno);
 298         for (i = 0; senders[i].name; i++) {
 299                 if (!senders[i].pre_select)
 300                         continue;
 301                 senders[i].pre_select(&s->max_fileno, &s->rfds, &s->wfds);
 302         }
 303         tv = vss_compute_timeout(vsst);
 304         if (tv && tv_diff(tv, &s->timeout, &diff) < 0)
 305                 s->timeout = *tv;
 306 }
 307
 308 static int recv_afs_msg(int afs_socket, int *fd, uint32_t *code, uint32_t *data)
 309 {
 310         char control[255], buf[8];
 311         struct msghdr msg = {.msg_iov = NULL};
 312         struct cmsghdr *cmsg;
 313         struct iovec iov;
 314         int ret = 0;
 315
 316         *fd = -1;
 317         iov.iov_base = buf;
 318         iov.iov_len = sizeof(buf);
 319         msg.msg_iov = &iov;
 320         msg.msg_iovlen = 1;
 321         msg.msg_control = control;
 322         msg.msg_controllen = sizeof(control);
 323         memset(buf, 0, sizeof(buf));
 324         ret = recvmsg(afs_socket, &msg, 0);
 325         if (ret < 0)
 326                 return -ERRNO_TO_PARA_ERROR(errno);
 327         if (iov.iov_len != sizeof(buf))
 328                 return -E_AFS_SHORT_READ;
 329         *code = *(uint32_t*)buf;
 330         *data =  *(uint32_t*)(buf + 4);
 331         for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
 332                 if (cmsg->cmsg_level != SOL_SOCKET
 333                         || cmsg->cmsg_type != SCM_RIGHTS)
 334                 continue;
 335                 if ((cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int) != 1)
 336                 continue;
 337                 *fd = *(int *)CMSG_DATA(cmsg);
 338         }
 339         return 1;
 340 }
 341
 342 static void recv_afs_result(struct vss_task *vsst)
 343 {
 344         int ret, passed_fd, shmid;
 345         uint32_t afs_code = 0, afs_data = 0;
 346         struct stat statbuf;
 347
 348         vsst->afsss = AFS_SOCKET_READY;
 349         mmd->afd.afhi.chunk_table = NULL;
 350         ret = recv_afs_msg(vsst->afs_socket, &passed_fd, &afs_code, &afs_data);
 351         if (ret < 0)
 352                 goto err;
 353         PARA_DEBUG_LOG("fd: %d, code: %u, shmid: %u\n", passed_fd, afs_code,
 354                 afs_data);
 355         ret = -E_NOFD;
 356         if (afs_code != NEXT_AUDIO_FILE)
 357                 goto err;
 358         if (passed_fd < 0)
 359                 goto err;
 360         shmid = afs_data;
 361         ret = load_afd(shmid, &mmd->afd);
 362         if (ret < 0)
 363                 goto err;
 364         shm_destroy(shmid);
 365         ret = fstat(passed_fd, &statbuf);
 366         if (ret < 0) {
 367                 PARA_ERROR_LOG("fstat error:\n");
 368                 ret = -ERRNO_TO_PARA_ERROR(errno);
 369                 goto err;
 370         }
 371         mmd->size = statbuf.st_size;
 372         mmd->mtime = statbuf.st_mtime;
 373         vsst->map = para_mmap(mmd->size, PROT_READ, MAP_PRIVATE,
 374                 passed_fd, 0);
 375         close(passed_fd);
 376         mmd->chunks_sent = 0;
 377         mmd->current_chunk = 0;
 378         mmd->offset = 0;
 379         mmd->events++;
 380         mmd->num_played++;
 381         mmd->new_vss_status_flags &= (~VSS_NEXT);
 382         tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
 383         afh_get_header(&mmd->afd.afhi, vsst->map, &vsst->header_buf,
 384                 &vsst->header_len);
 385         return;
 386 err:
 387         free(mmd->afd.afhi.chunk_table);
 388         if (passed_fd >= 0)
 389                 close(passed_fd);
 390         PARA_ERROR_LOG("%s\n", para_strerror(-ret));
 391         mmd->new_vss_status_flags = VSS_NEXT;
 392 }
 393
 394 /**
 395  * Main sending function.
 396  *
 397  * This function gets called from para_server as soon as the next chunk of data
 398  * should be pushed out. It obtains a pointer to the data to be sent out as
 399  * well as its length from mmd->afd.afhi. This information is then passed to
 400  * each supported sender's send() function which is supposed to send out the data
 401  * to all connected clients.
 402  */
 403 static void vss_send_chunk(struct vss_task *vsst)
 404 {
 405         int i;
 406         struct timeval due;
 407         const char *buf;
 408         size_t len;
 409
 410         if (!vsst->map || !vss_playing())
 411                 return;
 412         compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
 413                 &mmd->stream_start, &due);
 414         if (tv_diff(&due, now, NULL) > 0)
 415                 return;
 416         if (chk_barrier("eof", &vsst->eof_barrier, &due, 1) < 0)
 417                 return;
 418         if (chk_barrier("data send", &vsst->data_send_barrier,
 419                         &due, 1) < 0)
 420                 return;
 421         if (mmd->current_chunk >= mmd->afd.afhi.chunks_total) { /* eof */
 422                 mmd->new_vss_status_flags |= VSS_NEXT;
 423                 return;
 424         }
 425         /*
 426          * We call the send function also in case of empty chunks as they
 427          * might have still some data queued which can be sent in this case.
 428          */
 429         if (!mmd->chunks_sent) {
 430                 struct timeval tmp;
 431                 mmd->stream_start = *now;
 432                 tv_scale(mmd->current_chunk, &mmd->afd.afhi.chunk_tv, &tmp);
 433                 mmd->offset = tv2ms(&tmp);
 434                 mmd->events++;
 435         }
 436         afh_get_chunk(mmd->current_chunk, &mmd->afd.afhi, vsst->map, &buf, &len);
 437         for (i = 0; senders[i].name; i++)
 438                 senders[i].send(mmd->current_chunk, mmd->chunks_sent, buf, len,
 439                         vsst->header_buf, vsst->header_len);
 440         mmd->new_vss_status_flags |= VSS_PLAYING;
 441         mmd->chunks_sent++;
 442         mmd->current_chunk++;
 443 }
 444
 445 static void vss_post_select(struct sched *s, struct task *t)
 446 {
 447         int ret, i;
 448         struct vss_task *vsst = container_of(t, struct vss_task, task);
 449
 450         if (mmd->sender_cmd_data.cmd_num >= 0) {
 451                 int num = mmd->sender_cmd_data.cmd_num,
 452                         sender_num = mmd->sender_cmd_data.sender_num;
 453
 454                 if (senders[sender_num].client_cmds[num])
 455                         senders[sender_num].client_cmds[num](&mmd->sender_cmd_data);
 456                 mmd->sender_cmd_data.cmd_num = -1;
 457         }
 458         if (vsst->afsss != AFS_SOCKET_CHECK_FOR_WRITE) {
 459                 if (FD_ISSET(vsst->afs_socket, &s->rfds))
 460                         recv_afs_result(vsst);
 461         } else if (FD_ISSET(vsst->afs_socket, &s->wfds)) {
 462                 PARA_NOTICE_LOG("requesting new fd from afs\n");
 463                 ret = send_buffer(vsst->afs_socket, "new");
 464                 vsst->afsss = AFS_SOCKET_AFD_PENDING;
 465         }
 466         for (i = 0; senders[i].name; i++) {
 467                 if (!senders[i].post_select)
 468                         continue;
 469                 senders[i].post_select(&s->rfds, &s->wfds);
 470         }
 471         vss_send_chunk(vsst);
 472 }
 473
 474 /**
 475  * Initialize the virtual streaming system task.
 476  *
 477  * \param afs_socket The fd for communication with afs.
 478  *
 479  * This also initializes all supported senders and starts streaming
 480  * if the --autoplay command line flag was given.
 481  */
 482 void init_vss_task(int afs_socket)
 483 {
 484         static struct vss_task vss_task_struct, *vsst = &vss_task_struct;
 485         int i;
 486         char *hn = para_hostname(), *home = para_homedir();
 487         long unsigned announce_time = conf.announce_time_arg > 0?
 488                         conf.announce_time_arg : 300,
 489                 autoplay_delay = conf.autoplay_delay_arg > 0?
 490                         conf.autoplay_delay_arg : 0;
 491
 492         vsst->afs_socket = afs_socket;
 493         vsst->task.pre_select = vss_pre_select;
 494         vsst->task.post_select = vss_post_select;
 495         ms2tv(announce_time, &vsst->announce_tv);
 496         PARA_INFO_LOG("announce timeval: %lums\n", tv2ms(&vsst->announce_tv));
 497         for (i = 0; senders[i].name; i++) {
 498                 PARA_NOTICE_LOG("initializing %s sender\n", senders[i].name);
 499                 senders[i].init(&senders[i]);
 500         }
 501         free(hn);
 502         free(home);
 503         mmd->sender_cmd_data.cmd_num = -1;
 504         if (conf.autoplay_given) {
 505                 struct timeval tmp;
 506                 mmd->vss_status_flags |= VSS_PLAYING;
 507                 mmd->new_vss_status_flags |= VSS_PLAYING;
 508                 ms2tv(autoplay_delay, &tmp);
 509                 tv_add(now, &tmp, &vsst->autoplay_barrier);
 510         }
 511         register_task(&vsst->task);
 512 }