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 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         if (vsst->map) /* have audio file */
 240                 return 0;
 241         if (!vss_playing()) /* don't need one */
 242                 return 0;
 243         if (mmd->new_vss_status_flags & VSS_NOMORE)
 244                 return 0;
 245         if (vsst->afsss == AFS_SOCKET_AFD_PENDING) /* already requested one */
 246                 return 0;
 247         return 1;
 248 }
 249
 250 /**
 251  * Compute the timeout for para_server's main select-loop.
 252  *
 253  * This function gets called from para_server to determine the timeout value
 254  * for its main select loop.
 255  *
 256  * \param s Pointer to the server scheduler.
 257  * \param t Pointer to the vss task structure.
 258  *
 259  * Before the timeout is computed, the current vss status flags are evaluated
 260  * and acted upon by calling appropriate functions from the lower layers.
 261  * Possible actions include
 262  *
 263  *      - request a new audio file from afs,
 264  *      - shutdown of all senders (stop/pause command),
 265  *      - reposition the stream (ff/jmp command).
 266  */
 267 static void vss_pre_select(struct sched *s, struct task *t)
 268 {
 269         int i;
 270         struct timeval *tv, diff;
 271         struct vss_task *vsst = container_of(t, struct vss_task, task);
 272
 273         if (!vsst->map || vss_next() || vss_paused() || vss_repos())
 274                 for (i = 0; senders[i].name; i++)
 275                         senders[i].shutdown_clients();
 276         if (vss_next())
 277                 vss_eof(vsst);
 278         else if (vss_paused()) {
 279                 if (mmd->chunks_sent)
 280                         tv_add(&mmd->afd.afhi.eof_tv, now, &vsst->eof_barrier);
 281                 mmd->chunks_sent = 0;
 282         } else if (vss_repos()) {
 283                 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
 284                 tv_add(&mmd->afd.afhi.eof_tv, now, &vsst->eof_barrier);
 285                 mmd->chunks_sent = 0;
 286                 mmd->current_chunk = mmd->repos_request;
 287                 mmd->new_vss_status_flags &= ~VSS_REPOS;
 288         }
 289
 290         if (need_to_request_new_audio_file(vsst)) {
 291                 PARA_DEBUG_LOG("ready and playing, but no audio file\n");
 292                 para_fd_set(vsst->afs_socket, &s->wfds, &s->max_fileno);
 293                 vsst->afsss = AFS_SOCKET_CHECK_FOR_WRITE;
 294         } else
 295                 para_fd_set(vsst->afs_socket, &s->rfds, &s->max_fileno);
 296         for (i = 0; senders[i].name; i++) {
 297                 if (!senders[i].pre_select)
 298                         continue;
 299                 senders[i].pre_select(&s->max_fileno, &s->rfds, &s->wfds);
 300         }
 301         tv = vss_compute_timeout(vsst);
 302         if (tv && tv_diff(tv, &s->timeout, &diff) < 0)
 303                 s->timeout = *tv;
 304 }
 305
 306 static int recv_afs_msg(int afs_socket, int *fd, uint32_t *code, uint32_t *data)
 307 {
 308         char control[255], buf[8];
 309         struct msghdr msg = {.msg_iov = NULL};
 310         struct cmsghdr *cmsg;
 311         struct iovec iov;
 312         int ret = 0;
 313
 314         *fd = -1;
 315         iov.iov_base = buf;
 316         iov.iov_len = sizeof(buf);
 317         msg.msg_iov = &iov;
 318         msg.msg_iovlen = 1;
 319         msg.msg_control = control;
 320         msg.msg_controllen = sizeof(control);
 321         memset(buf, 0, sizeof(buf));
 322         ret = recvmsg(afs_socket, &msg, 0);
 323         if (ret < 0)
 324                 return -ERRNO_TO_PARA_ERROR(errno);
 325         if (iov.iov_len != sizeof(buf))
 326                 return -E_AFS_SHORT_READ;
 327         *code = *(uint32_t*)buf;
 328         *data =  *(uint32_t*)(buf + 4);
 329         for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
 330                 if (cmsg->cmsg_level != SOL_SOCKET
 331                         || cmsg->cmsg_type != SCM_RIGHTS)
 332                 continue;
 333                 if ((cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int) != 1)
 334                 continue;
 335                 *fd = *(int *)CMSG_DATA(cmsg);
 336         }
 337         return 1;
 338 }
 339
 340 static void recv_afs_result(struct vss_task *vsst)
 341 {
 342         int ret, passed_fd, shmid;
 343         uint32_t afs_code = 0, afs_data = 0;
 344         struct stat statbuf;
 345
 346         vsst->afsss = AFS_SOCKET_READY;
 347         mmd->afd.afhi.chunk_table = NULL;
 348         ret = recv_afs_msg(vsst->afs_socket, &passed_fd, &afs_code, &afs_data);
 349         if (ret < 0)
 350                 goto err;
 351         PARA_DEBUG_LOG("fd: %d, code: %u, shmid: %u\n", passed_fd, afs_code,
 352                 afs_data);
 353         ret = -E_NOFD;
 354         if (afs_code != NEXT_AUDIO_FILE)
 355                 goto err;
 356         if (passed_fd < 0)
 357                 goto err;
 358         shmid = afs_data;
 359         ret = load_afd(shmid, &mmd->afd);
 360         if (ret < 0)
 361                 goto err;
 362         shm_destroy(shmid);
 363         ret = fstat(passed_fd, &statbuf);
 364         if (ret < 0) {
 365                 PARA_ERROR_LOG("fstat error:\n");
 366                 ret = -ERRNO_TO_PARA_ERROR(errno);
 367                 goto err;
 368         }
 369         mmd->size = statbuf.st_size;
 370         mmd->mtime = statbuf.st_mtime;
 371         vsst->map = para_mmap(mmd->size, PROT_READ, MAP_PRIVATE,
 372                 passed_fd, 0);
 373         close(passed_fd);
 374         mmd->chunks_sent = 0;
 375         mmd->current_chunk = 0;
 376         mmd->offset = 0;
 377         mmd->events++;
 378         mmd->num_played++;
 379         mmd->new_vss_status_flags &= (~VSS_NEXT);
 380         tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
 381         afh_get_header(&mmd->afd.afhi, vsst->map, &vsst->header_buf,
 382                 &vsst->header_len);
 383         return;
 384 err:
 385         free(mmd->afd.afhi.chunk_table);
 386         if (passed_fd >= 0)
 387                 close(passed_fd);
 388         PARA_ERROR_LOG("%s\n", para_strerror(-ret));
 389         mmd->new_vss_status_flags = VSS_NEXT;
 390 }
 391
 392 /**
 393  * Main sending function.
 394  *
 395  * This function gets called from para_server as soon as the next chunk of data
 396  * should be pushed out. It obtains a pointer to the data to be sent out as
 397  * well as its length from mmd->afd.afhi. This information is then passed to
 398  * each supported sender's send() function which is supposed to send out the data
 399  * to all connected clients.
 400  */
 401 static void vss_send_chunk(struct vss_task *vsst)
 402 {
 403         int i;
 404         struct timeval due;
 405         const char *buf;
 406         size_t len;
 407
 408         if (!vsst->map || !vss_playing())
 409                 return;
 410         compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
 411                 &mmd->stream_start, &due);
 412         if (tv_diff(&due, now, NULL) > 0)
 413                 return;
 414         if (chk_barrier("eof", &vsst->eof_barrier, &due, 1) < 0)
 415                 return;
 416         if (chk_barrier("data send", &vsst->data_send_barrier,
 417                         &due, 1) < 0)
 418                 return;
 419         if (mmd->current_chunk >= mmd->afd.afhi.chunks_total) { /* eof */
 420                 mmd->new_vss_status_flags |= VSS_NEXT;
 421                 return;
 422         }
 423         /*
 424          * We call the send function also in case of empty chunks as they
 425          * might have still some data queued which can be sent in this case.
 426          */
 427         if (!mmd->chunks_sent) {
 428                 struct timeval tmp;
 429                 mmd->stream_start = *now;
 430                 tv_scale(mmd->current_chunk, &mmd->afd.afhi.chunk_tv, &tmp);
 431                 mmd->offset = tv2ms(&tmp);
 432                 mmd->events++;
 433         }
 434         afh_get_chunk(mmd->current_chunk, &mmd->afd.afhi, vsst->map, &buf, &len);
 435         for (i = 0; senders[i].name; i++)
 436                 senders[i].send(mmd->current_chunk, mmd->chunks_sent, buf, len,
 437                         vsst->header_buf, vsst->header_len);
 438         mmd->new_vss_status_flags |= VSS_PLAYING;
 439         mmd->chunks_sent++;
 440         mmd->current_chunk++;
 441 }
 442
 443 static void vss_post_select(struct sched *s, struct task *t)
 444 {
 445         int ret, i;
 446         struct vss_task *vsst = container_of(t, struct vss_task, task);
 447
 448         if (mmd->sender_cmd_data.cmd_num >= 0) {
 449                 int num = mmd->sender_cmd_data.cmd_num,
 450                         sender_num = mmd->sender_cmd_data.sender_num;
 451
 452                 if (senders[sender_num].client_cmds[num])
 453                         senders[sender_num].client_cmds[num](&mmd->sender_cmd_data);
 454                 mmd->sender_cmd_data.cmd_num = -1;
 455         }
 456         if (vsst->afsss != AFS_SOCKET_CHECK_FOR_WRITE) {
 457                 if (FD_ISSET(vsst->afs_socket, &s->rfds))
 458                         recv_afs_result(vsst);
 459         } else if (FD_ISSET(vsst->afs_socket, &s->wfds)) {
 460                 PARA_NOTICE_LOG("requesting new fd from afs\n");
 461                 ret = send_buffer(vsst->afs_socket, "new");
 462                 vsst->afsss = AFS_SOCKET_AFD_PENDING;
 463         }
 464         for (i = 0; senders[i].name; i++) {
 465                 if (!senders[i].post_select)
 466                         continue;
 467                 senders[i].post_select(&s->rfds, &s->wfds);
 468         }
 469         vss_send_chunk(vsst);
 470 }
 471
 472 /**
 473  * Initialize the virtual streaming system task.
 474  *
 475  * \param afs_socket The fd for communication with afs.
 476  *
 477  * This also initializes all supported senders and starts streaming
 478  * if the --autoplay command line flag was given.
 479  */
 480 void init_vss_task(int afs_socket)
 481 {
 482         static struct vss_task vss_task_struct, *vsst = &vss_task_struct;
 483         int i;
 484         char *hn = para_hostname(), *home = para_homedir();
 485         long unsigned announce_time = conf.announce_time_arg > 0?
 486                         conf.announce_time_arg : 300,
 487                 autoplay_delay = conf.autoplay_delay_arg > 0?
 488                         conf.autoplay_delay_arg : 0;
 489
 490         vsst->afs_socket = afs_socket;
 491         vsst->task.pre_select = vss_pre_select;
 492         vsst->task.post_select = vss_post_select;
 493         ms2tv(announce_time, &vsst->announce_tv);
 494         PARA_INFO_LOG("announce timeval: %lums\n", tv2ms(&vsst->announce_tv));
 495         for (i = 0; senders[i].name; i++) {
 496                 PARA_NOTICE_LOG("initializing %s sender\n", senders[i].name);
 497                 senders[i].init(&senders[i]);
 498         }
 499         free(hn);
 500         free(home);
 501         mmd->sender_cmd_data.cmd_num = -1;
 502         make_empty_status_items(mmd->afd.verbose_ls_output);
 503         if (conf.autoplay_given) {
 504                 struct timeval tmp;
 505                 mmd->vss_status_flags |= VSS_PLAYING;
 506                 mmd->new_vss_status_flags |= VSS_PLAYING;
 507                 ms2tv(autoplay_delay, &tmp);
 508                 tv_add(now, &tmp, &vsst->autoplay_barrier);
 509         }
 510         register_task(&vsst->task);
 511 }