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         struct timeval announce_tv;
  69         struct timeval data_send_barrier;
  70         struct timeval eof_barrier;
  71         struct timeval autoplay_barrier;
  72         int afs_socket;
  73         enum afs_socket_status afsss;
  74         char *map;
  75         struct task task;
  76         const char *header_buf;
  77         size_t header_len;
  78 };
  79
  80 /**
  81  * Check if vss status flag \a P (playing) is set.
  82  *
  83  * \return Greater than zero if playing, zero otherwise.
  84  *
  85  */
  86 unsigned int vss_playing(void)
  87 {
  88         return mmd->new_vss_status_flags & VSS_PLAYING;
  89 }
  90
  91 /**
  92  * Check if the \a N (next) status flag is set.
  93  *
  94  * \return Greater than zero if set, zero if not.
  95  *
  96  */
  97 unsigned int vss_next(void)
  98 {
  99         return mmd->new_vss_status_flags & VSS_NEXT;
 100 }
 101
 102 /**
 103  * Check if a reposition request is pending.
 104  *
 105  * \return Greater than zero if true, zero otherwise.
 106  *
 107  */
 108 unsigned int vss_repos(void)
 109 {
 110         return mmd->new_vss_status_flags & VSS_REPOS;
 111 }
 112
 113 /**
 114  * Check if the vss is currently paused.
 115  *
 116  * \return Greater than zero if paused, zero otherwise.
 117  *
 118  */
 119 unsigned int vss_paused(void)
 120 {
 121         return !(mmd->new_vss_status_flags & VSS_NEXT)
 122                 && !(mmd->new_vss_status_flags & VSS_PLAYING);
 123 }
 124
 125 /**
 126  * Check if the vss is currently stopped.
 127  *
 128  * \return Greater than zero if paused, zero otherwise.
 129  *
 130  */
 131 unsigned int vss_stopped(void)
 132 {
 133         return (mmd->new_vss_status_flags & VSS_NEXT)
 134                 && !(mmd->new_vss_status_flags & VSS_PLAYING);
 135 }
 136
 137 static int chk_barrier(const char *bname, const struct timeval *barrier,
 138                 struct timeval *diff, int print_log)
 139 {
 140         long ms;
 141
 142         if (tv_diff(now, barrier, diff) > 0)
 143                 return 1;
 144         ms = tv2ms(diff);
 145         if (print_log && ms)
 146                 PARA_DEBUG_LOG("%s barrier: %lims left\n", bname, ms);
 147         return -1;
 148 }
 149
 150 /*
 151  * != NULL: timeout for next chunk
 152  * NULL: nothing to do
 153  */
 154 static struct timeval *vss_compute_timeout(struct vss_task *vsst)
 155 {
 156         static struct timeval the_timeout;
 157         struct timeval next_chunk;
 158
 159         if (vss_next() && vsst->map) {
 160                 /* only sleep a bit, nec*/
 161                 the_timeout.tv_sec = 0;
 162                 the_timeout.tv_usec = 100;
 163                 return &the_timeout;
 164         }
 165         if (chk_barrier("autoplay_delay", &vsst->autoplay_barrier,
 166                         &the_timeout, 1) < 0)
 167                 return &the_timeout;
 168         if (chk_barrier("eof", &vsst->eof_barrier, &the_timeout, 1) < 0)
 169                 return &the_timeout;
 170         if (chk_barrier("data send", &vsst->data_send_barrier,
 171                         &the_timeout, 1) < 0)
 172                 return &the_timeout;
 173         if (!vss_playing() || !vsst->map)
 174                 return NULL;
 175         compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
 176                 &mmd->stream_start, &next_chunk);
 177         if (chk_barrier("chunk", &next_chunk, &the_timeout, 0) < 0)
 178                 return &the_timeout;
 179         /* chunk is due or bof */
 180         the_timeout.tv_sec = 0;
 181         the_timeout.tv_usec = 0;
 182         return &the_timeout;
 183 }
 184
 185 static void vss_eof(struct vss_task *vsst)
 186 {
 187         mmd->stream_start = *now;
 188         if (!vsst->map)
 189                 return;
 190         if (mmd->new_vss_status_flags & VSS_NOMORE)
 191                 mmd->new_vss_status_flags = VSS_NEXT;
 192         tv_add(&mmd->afd.afhi.eof_tv, now, &vsst->eof_barrier);
 193         para_munmap(vsst->map, mmd->size);
 194         vsst->map = NULL;
 195         mmd->chunks_sent = 0;
 196         mmd->offset = 0;
 197         mmd->afd.afhi.seconds_total = 0;
 198         mmd->afd.afhi.chunk_tv.tv_sec = 0;
 199         mmd->afd.afhi.chunk_tv.tv_usec = 0;
 200         free(mmd->afd.afhi.chunk_table);
 201         mmd->afd.afhi.chunk_table = NULL;
 202         free(mmd->afd.afhi.info_string);
 203         mmd->afd.afhi.info_string = make_message("%s:\n%s:\n%s:\n", status_item_list[SI_AUDIO_FILE_INFO],
 204                 status_item_list[SI_TAGINFO1], status_item_list[SI_TAGINFO2]);
 205         make_empty_status_items(mmd->afd.verbose_ls_output);
 206         mmd->mtime = 0;
 207         mmd->size = 0;
 208         mmd->events++;
 209 }
 210
 211 /**
 212  * Get the list of all supported audio formats.
 213  *
 214  * \return Aa space separated list of all supported audio formats
 215  * It is not allocated at runtime, i.e. there is no need to free
 216  * the returned string in the caller.
 217  */
 218 const char *supported_audio_formats(void)
 219 {
 220         return SUPPORTED_AUDIO_FORMATS;
 221 }
 222
 223 /**
 224  * Get the chunk time of the current audio file.
 225  *
 226  * \return A pointer to a struct containing the chunk time, or NULL,
 227  * if currently no audio file is selected.
 228  */
 229 struct timeval *vss_chunk_time(void)
 230 {
 231         if (mmd->afd.afhi.chunk_tv.tv_sec == 0 &&
 232                         mmd->afd.afhi.chunk_tv.tv_usec == 0)
 233                 return NULL;
 234         return &mmd->afd.afhi.chunk_tv;
 235 }
 236
 237 static int need_to_request_new_audio_file(struct vss_task *vsst)
 238 {
 239         struct timeval diff;
 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         if (chk_barrier("autoplay_delay", &vsst->autoplay_barrier,
 250                         &diff, 1) < 0)
 251                 return 0;
 252         return 1;
 253 }
 254
 255 /**
 256  * Compute the timeout for para_server's main select-loop.
 257  *
 258  * This function gets called from para_server to determine the timeout value
 259  * for its main select loop.
 260  *
 261  * \param s Pointer to the server scheduler.
 262  * \param t Pointer to the vss task structure.
 263  *
 264  * Before the timeout is computed, the current vss status flags are evaluated
 265  * and acted upon by calling appropriate functions from the lower layers.
 266  * Possible actions include
 267  *
 268  *      - request a new audio file from afs,
 269  *      - shutdown of all senders (stop/pause command),
 270  *      - reposition the stream (ff/jmp command).
 271  */
 272 static void vss_pre_select(struct sched *s, struct task *t)
 273 {
 274         int i;
 275         struct timeval *tv, diff;
 276         struct vss_task *vsst = container_of(t, struct vss_task, task);
 277
 278         if (!vsst->map || vss_next() || vss_paused() || vss_repos())
 279                 for (i = 0; senders[i].name; i++)
 280                         senders[i].shutdown_clients();
 281         if (vss_next())
 282                 vss_eof(vsst);
 283         else if (vss_paused()) {
 284                 if (mmd->chunks_sent)
 285                         tv_add(&mmd->afd.afhi.eof_tv, now, &vsst->eof_barrier);
 286                 mmd->chunks_sent = 0;
 287         } else if (vss_repos()) {
 288                 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
 289                 tv_add(&mmd->afd.afhi.eof_tv, now, &vsst->eof_barrier);
 290                 mmd->chunks_sent = 0;
 291                 mmd->current_chunk = mmd->repos_request;
 292                 mmd->new_vss_status_flags &= ~VSS_REPOS;
 293         }
 294         if (need_to_request_new_audio_file(vsst)) {
 295                 PARA_DEBUG_LOG("ready and playing, but no audio file\n");
 296                 para_fd_set(vsst->afs_socket, &s->wfds, &s->max_fileno);
 297                 vsst->afsss = AFS_SOCKET_CHECK_FOR_WRITE;
 298         } else
 299                 para_fd_set(vsst->afs_socket, &s->rfds, &s->max_fileno);
 300         for (i = 0; senders[i].name; i++) {
 301                 if (!senders[i].pre_select)
 302                         continue;
 303                 senders[i].pre_select(&s->max_fileno, &s->rfds, &s->wfds);
 304         }
 305         tv = vss_compute_timeout(vsst);
 306         if (tv && tv_diff(tv, &s->timeout, &diff) < 0)
 307                 s->timeout = *tv;
 308 }
 309
 310 static int recv_afs_msg(int afs_socket, int *fd, uint32_t *code, uint32_t *data)
 311 {
 312         char control[255], buf[8];
 313         struct msghdr msg = {.msg_iov = NULL};
 314         struct cmsghdr *cmsg;
 315         struct iovec iov;
 316         int ret = 0;
 317
 318         *fd = -1;
 319         iov.iov_base = buf;
 320         iov.iov_len = sizeof(buf);
 321         msg.msg_iov = &iov;
 322         msg.msg_iovlen = 1;
 323         msg.msg_control = control;
 324         msg.msg_controllen = sizeof(control);
 325         memset(buf, 0, sizeof(buf));
 326         ret = recvmsg(afs_socket, &msg, 0);
 327         if (ret < 0)
 328                 return -ERRNO_TO_PARA_ERROR(errno);
 329         if (iov.iov_len != sizeof(buf))
 330                 return -E_AFS_SHORT_READ;
 331         *code = *(uint32_t*)buf;
 332         *data =  *(uint32_t*)(buf + 4);
 333         for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
 334                 if (cmsg->cmsg_level != SOL_SOCKET
 335                         || cmsg->cmsg_type != SCM_RIGHTS)
 336                 continue;
 337                 if ((cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int) != 1)
 338                 continue;
 339                 *fd = *(int *)CMSG_DATA(cmsg);
 340         }
 341         return 1;
 342 }
 343
 344 static void recv_afs_result(struct vss_task *vsst)
 345 {
 346         int ret, passed_fd, shmid;
 347         uint32_t afs_code = 0, afs_data = 0;
 348         struct stat statbuf;
 349
 350         vsst->afsss = AFS_SOCKET_READY;
 351         mmd->afd.afhi.chunk_table = NULL;
 352         ret = recv_afs_msg(vsst->afs_socket, &passed_fd, &afs_code, &afs_data);
 353         if (ret < 0)
 354                 goto err;
 355         PARA_DEBUG_LOG("fd: %d, code: %u, shmid: %u\n", passed_fd, afs_code,
 356                 afs_data);
 357         ret = -E_NOFD;
 358         if (afs_code != NEXT_AUDIO_FILE)
 359                 goto err;
 360         if (passed_fd < 0)
 361                 goto err;
 362         shmid = afs_data;
 363         ret = load_afd(shmid, &mmd->afd);
 364         if (ret < 0)
 365                 goto err;
 366         shm_destroy(shmid);
 367         ret = fstat(passed_fd, &statbuf);
 368         if (ret < 0) {
 369                 PARA_ERROR_LOG("fstat error:\n");
 370                 ret = -ERRNO_TO_PARA_ERROR(errno);
 371                 goto err;
 372         }
 373         mmd->size = statbuf.st_size;
 374         mmd->mtime = statbuf.st_mtime;
 375         vsst->map = para_mmap(mmd->size, PROT_READ, MAP_PRIVATE,
 376                 passed_fd, 0);
 377         close(passed_fd);
 378         mmd->chunks_sent = 0;
 379         mmd->current_chunk = 0;
 380         mmd->offset = 0;
 381         mmd->events++;
 382         mmd->num_played++;
 383         mmd->new_vss_status_flags &= (~VSS_NEXT);
 384         afh_get_header(&mmd->afd.afhi, vsst->map, &vsst->header_buf,
 385                 &vsst->header_len);
 386         return;
 387 err:
 388         free(mmd->afd.afhi.chunk_table);
 389         if (passed_fd >= 0)
 390                 close(passed_fd);
 391         PARA_ERROR_LOG("%s\n", para_strerror(-ret));
 392         mmd->new_vss_status_flags = VSS_NEXT;
 393 }
 394
 395 /**
 396  * Main sending function.
 397  *
 398  * This function gets called from para_server as soon as the next chunk of data
 399  * should be pushed out. It obtains a pointer to the data to be sent out as
 400  * well as its length from mmd->afd.afhi. This information is then passed to
 401  * each supported sender's send() function which is supposed to send out the data
 402  * to all connected clients.
 403  */
 404 static void vss_send_chunk(struct vss_task *vsst)
 405 {
 406         int i;
 407         struct timeval due;
 408         const char *buf;
 409         size_t len;
 410
 411         if (!vsst->map || !vss_playing())
 412                 return;
 413         compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
 414                 &mmd->stream_start, &due);
 415         if (tv_diff(&due, now, NULL) > 0)
 416                 return;
 417         if (chk_barrier("eof", &vsst->eof_barrier, &due, 1) < 0)
 418                 return;
 419         if (chk_barrier("data send", &vsst->data_send_barrier,
 420                         &due, 1) < 0)
 421                 return;
 422         if (mmd->current_chunk >= mmd->afd.afhi.chunks_total) { /* eof */
 423                 mmd->new_vss_status_flags |= VSS_NEXT;
 424                 return;
 425         }
 426         /*
 427          * We call the send function also in case of empty chunks as they
 428          * might have still some data queued which can be sent in this case.
 429          */
 430         if (!mmd->chunks_sent) {
 431                 struct timeval tmp;
 432                 mmd->stream_start = *now;
 433                 tv_scale(mmd->current_chunk, &mmd->afd.afhi.chunk_tv, &tmp);
 434                 mmd->offset = tv2ms(&tmp);
 435                 mmd->events++;
 436         }
 437         afh_get_chunk(mmd->current_chunk, &mmd->afd.afhi, vsst->map, &buf, &len);
 438         for (i = 0; senders[i].name; i++)
 439                 senders[i].send(mmd->current_chunk, mmd->chunks_sent, buf, len,
 440                         vsst->header_buf, vsst->header_len);
 441         mmd->new_vss_status_flags |= VSS_PLAYING;
 442         mmd->chunks_sent++;
 443         mmd->current_chunk++;
 444 }
 445
 446 static void vss_post_select(struct sched *s, struct task *t)
 447 {
 448         int ret, i;
 449         struct vss_task *vsst = container_of(t, struct vss_task, task);
 450
 451         if (mmd->sender_cmd_data.cmd_num >= 0) {
 452                 int num = mmd->sender_cmd_data.cmd_num,
 453                         sender_num = mmd->sender_cmd_data.sender_num;
 454
 455                 if (senders[sender_num].client_cmds[num])
 456                         senders[sender_num].client_cmds[num](&mmd->sender_cmd_data);
 457                 mmd->sender_cmd_data.cmd_num = -1;
 458         }
 459         if (vsst->afsss != AFS_SOCKET_CHECK_FOR_WRITE) {
 460                 if (FD_ISSET(vsst->afs_socket, &s->rfds))
 461                         recv_afs_result(vsst);
 462         } else if (FD_ISSET(vsst->afs_socket, &s->wfds)) {
 463                 PARA_NOTICE_LOG("requesting new fd from afs\n");
 464                 ret = send_buffer(vsst->afs_socket, "new");
 465                 vsst->afsss = AFS_SOCKET_AFD_PENDING;
 466         }
 467         for (i = 0; senders[i].name; i++) {
 468                 if (!senders[i].post_select)
 469                         continue;
 470                 senders[i].post_select(&s->rfds, &s->wfds);
 471         }
 472         if ((vss_playing() && !(mmd->vss_status_flags & VSS_PLAYING)) ||
 473                         (vss_next() && vss_playing()))
 474                 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
 475         vss_send_chunk(vsst);
 476 }
 477
 478 /**
 479  * Initialize the virtual streaming system task.
 480  *
 481  * \param afs_socket The fd for communication with afs.
 482  *
 483  * This also initializes all supported senders and starts streaming
 484  * if the --autoplay command line flag was given.
 485  */
 486 void init_vss_task(int afs_socket)
 487 {
 488         static struct vss_task vss_task_struct, *vsst = &vss_task_struct;
 489         int i;
 490         char *hn = para_hostname(), *home = para_homedir();
 491         long unsigned announce_time = conf.announce_time_arg > 0?
 492                         conf.announce_time_arg : 300,
 493                 autoplay_delay = conf.autoplay_delay_arg > 0?
 494                         conf.autoplay_delay_arg : 0;
 495
 496         vsst->afs_socket = afs_socket;
 497         vsst->task.pre_select = vss_pre_select;
 498         vsst->task.post_select = vss_post_select;
 499         ms2tv(announce_time, &vsst->announce_tv);
 500         PARA_INFO_LOG("announce timeval: %lums\n", tv2ms(&vsst->announce_tv));
 501         for (i = 0; senders[i].name; i++) {
 502                 PARA_NOTICE_LOG("initializing %s sender\n", senders[i].name);
 503                 senders[i].init(&senders[i]);
 504         }
 505         free(hn);
 506         free(home);
 507         mmd->sender_cmd_data.cmd_num = -1;
 508         make_empty_status_items(mmd->afd.verbose_ls_output);
 509         if (conf.autoplay_given) {
 510                 struct timeval tmp;
 511                 mmd->vss_status_flags |= VSS_PLAYING;
 512                 mmd->new_vss_status_flags |= VSS_PLAYING;
 513                 ms2tv(autoplay_delay, &tmp);
 514                 tv_add(now, &tmp, &vsst->autoplay_barrier);
 515                 tv_add(&vsst->autoplay_barrier, &vsst->announce_tv,
 516                         &vsst->data_send_barrier);
 517         }
 518         register_task(&vsst->task);
 519 }