2 * Copyright (C) 1997-2009 Andre Noll <maan@systemlinux.org>
4 * Licensed under the GPL v2. For licencing details see COPYING.
7 /** \file vss.c The virtual streaming system.
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
18 #include "portable_io.h"
25 #include "server.cmdline.h"
33 extern struct misc_meta_data *mmd;
35 extern void dccp_send_init(struct sender *);
36 extern void http_send_init(struct sender *);
37 extern void udp_send_init(struct sender *);
39 /** The list of supported senders. */
40 struct sender senders[] = {
43 .init = http_send_init,
47 .init = dccp_send_init,
51 .init = udp_send_init,
58 /** The possible states of the afs socket. */
59 enum afs_socket_status {
60 /** Socket is inactive. */
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
68 /** The task structure for the virtual streaming system. */
70 /** Copied from the -announce_time command line option. */
71 struct timeval announce_tv;
72 /** End of the announcing interval. */
73 struct timeval data_send_barrier;
74 /** End of the EOF interval. */
75 struct timeval eof_barrier;
76 /** Only used if --autoplay_delay was given. */
77 struct timeval autoplay_barrier;
78 /** Used for afs-server communication. */
80 /** The current state of \a afs_socket. */
81 enum afs_socket_status afsss;
82 /** The memory mapped audio file. */
84 /** Used by the scheduler. */
86 /** Pointer to the header of the mapped audio file. */
87 const char *header_buf;
88 /** Length of the audio file header. */
92 static struct list_head fec_client_list;
102 uint32_t first_chunk;
104 struct timeval duration;
105 struct timeval start;
106 struct timeval slice_duration;
110 struct fec_client_parms *fcp;
111 struct fec_parms *parms;
112 struct list_head node;
113 struct timeval stream_start;
114 int first_stream_chunk;
115 struct fec_group group;
116 struct fec_slice slice;
117 const unsigned char **src_data;
118 unsigned char *extra_src_buf;
119 size_t extra_src_buf_size;
120 unsigned char *enc_buf;
125 * Get the chunk time of the current audio file.
127 * \return A pointer to a struct containing the chunk time, or NULL,
128 * if currently no audio file is selected.
130 struct timeval *vss_chunk_time(void)
132 if (mmd->afd.afhi.chunk_tv.tv_sec == 0 &&
133 mmd->afd.afhi.chunk_tv.tv_usec == 0)
135 return &mmd->afd.afhi.chunk_tv;
138 static void setup_fec_group(struct fec_client *fc, struct vss_task *vsst)
140 uint32_t num_bytes = 0, chunk_num, max_group_size, last_payload_size;
141 int i, k = fc->fcp->data_slices_per_group;
142 const unsigned char *start_buf = NULL;
143 struct timeval tmp, *chunk_tv = vss_chunk_time();
146 max_group_size = (fc->fcp->max_slice_bytes - FEC_HEADER_SIZE) * k;
147 chunk_num = fc->group.first_chunk;
149 const unsigned char *buf;
152 if (chunk_num >= mmd->afd.afhi.chunks_total)
154 afh_get_chunk(chunk_num, &mmd->afd.afhi, vsst->map, (const char **)&buf, &len);
157 if (num_bytes + len > max_group_size)
163 fc->group.num_chunks = chunk_num - fc->group.first_chunk;
165 fc->group.bytes = num_bytes;
167 fc->slice.bytes = ROUND_UP(num_bytes, k) / k;
169 /* The last slice will not be fully used */
170 last_payload_size = num_bytes % fc->slice.bytes;
171 if (!last_payload_size)
172 last_payload_size = fc->slice.bytes;
174 tv_scale(fc->group.num_chunks, chunk_tv, &fc->group.duration);
175 tv_scale(fc->group.first_chunk - fc->first_stream_chunk, chunk_tv,
177 tv_add(&fc->stream_start, &tmp, &fc->group.start);
178 tv_divide(fc->fcp->slices_per_group, &fc->group.duration,
179 &fc->group.slice_duration);
181 for (i = 0; i < k; i++)
182 fc->src_data[i] = start_buf + i * fc->slice.bytes;
184 if ((char *)start_buf + k * fc->slice.bytes > vsst->map + mmd->size) {
185 /* can not use last slice as it goes beyond the map */
186 if (fc->extra_src_buf_size < fc->slice.bytes)
187 fc->extra_src_buf = para_realloc(fc->extra_src_buf, fc->slice.bytes);
188 memcpy(fc->extra_src_buf, start_buf + (k - 1) * fc->slice.bytes,
190 memset(fc->extra_src_buf + last_payload_size, 0,
191 fc->slice.bytes - last_payload_size);
192 fc->src_data[k - 1] = fc->extra_src_buf;
198 * Write a fec header to a buffer.
200 * \param buf The buffer to write to.
201 * \param h The fec header to write.
203 static void write_fec_header(struct fec_client *fc)
205 char *buf = (char *)fc->enc_buf;
207 write_u32(buf, FEC_MAGIC);
209 write_u8(buf + 4, fc->fcp->slices_per_group);
210 write_u8(buf + 5, fc->fcp->data_slices_per_group);
211 write_u32(buf + 6, (uint32_t)0); /* audio header len */
213 write_u32(buf + 10, fc->group.num);
214 write_u32(buf + 14, fc->group.bytes);
216 write_u8(buf + 18, fc->slice.num);
217 write_u16(buf + 20, fc->slice.bytes);
218 memset(buf + 22, 0, 11);
222 * Return a buffer that marks the end of the stream.
224 * \return The length of the eof buffer.
226 * This is used for (multicast) udp streaming where closing the socket on the
227 * sender might not give rise to an eof condition at the peer.
229 size_t vss_get_fec_eof_packet(const char **buf)
231 static const char fec_eof_packet[FEC_HEADER_SIZE] =
232 "\xec\x0d\xcc\xfe\0\0\0\0"
236 *buf = fec_eof_packet;
237 return FEC_HEADER_SIZE;
240 static void compute_next_fec_slice(struct fec_client *fc, struct vss_task *vsst)
242 if (fc->first_stream_chunk < 0) {
243 fc->stream_start = *now;
244 fc->first_stream_chunk = mmd->current_chunk;
245 fc->group.first_chunk = mmd->current_chunk;
247 setup_fec_group(fc, vsst);
248 } else if (fc->slice.num == fc->fcp->slices_per_group) {
249 fc->group.first_chunk += fc->group.num_chunks;
250 setup_fec_group(fc, vsst);
253 if (fc->enc_buf_size < fc->slice.bytes + FEC_HEADER_SIZE) {
254 fc->enc_buf_size = fc->slice.bytes + FEC_HEADER_SIZE;
255 fc->enc_buf = para_realloc(fc->enc_buf, fc->enc_buf_size);
257 write_fec_header(fc);
258 fec_encode(fc->parms, fc->src_data, fc->enc_buf + FEC_HEADER_SIZE,
259 fc->slice.num, fc->slice.bytes);
263 * Add one entry to the list of active fec clients.
265 * \param fcp Describes the fec parameters to be used for this client.
266 * \param result An opaque pointer that must be used by remove the client later.
270 int vss_add_fec_client(struct fec_client_parms *fcp, struct fec_client **result)
273 struct fec_client *fc;
275 if (fcp->max_slice_bytes < FEC_HEADER_SIZE + fcp->data_slices_per_group)
276 return -ERRNO_TO_PARA_ERROR(EINVAL);
277 fc = para_calloc(sizeof(*fc));
279 ret = fec_new(fcp->data_slices_per_group, fcp->slices_per_group,
283 fc->first_stream_chunk = -1; /* stream not yet started */
284 fc->src_data = para_malloc(fc->fcp->slices_per_group * sizeof(char *));
285 para_list_add(&fc->node, &fec_client_list);
296 * Remove one entry from the list of active fec clients.
298 * \param result The client to be removed.
300 void vss_del_fec_client(struct fec_client *fc)
305 free(fc->extra_src_buf);
311 * Compute if/when next slice is due. If it isn't due yet and \a diff is
312 * not \p Null, compute the time difference next - now, where
314 * next = stream_start + (first_group_chunk - first_stream_chunk)
315 * * chunk_time + slice_num * slice_time
317 static int next_slice_is_due(struct fec_client *fc, struct timeval *diff)
319 struct timeval tmp, next;
322 if (fc->first_stream_chunk < 0)
324 tv_scale(fc->slice.num, &fc->group.slice_duration, &tmp);
325 tv_add(&tmp, &fc->group.start, &next);
326 ret = tv_diff(&next, now, diff);
327 return ret < 0? 1 : 0;
330 static void compute_slice_timeout(struct timeval *timeout)
332 struct fec_client *fc;
334 assert(vss_playing());
335 list_for_each_entry(fc, &fec_client_list, node) {
337 int ret = next_slice_is_due(fc, &diff);
339 // PARA_NOTICE_LOG("diff: %lu, ret: %d\n", tv2ms(&diff), ret);
342 timeout->tv_usec = 0;
345 /* timeout = min(timeout, diff) */
346 if (tv_diff(&diff, timeout, NULL) < 0)
351 PARA_NOTICE_LOG("slice timeout: %lu:%lu\n", (long unsigned)timeout->tv_sec, (long unsigned)timeout->tv_usec);
355 * Check if vss status flag \a P (playing) is set.
357 * \return Greater than zero if playing, zero otherwise.
360 unsigned int vss_playing(void)
362 return mmd->new_vss_status_flags & VSS_PLAYING;
366 * Check if the \a N (next) status flag is set.
368 * \return Greater than zero if set, zero if not.
371 unsigned int vss_next(void)
373 return mmd->new_vss_status_flags & VSS_NEXT;
377 * Check if a reposition request is pending.
379 * \return Greater than zero if true, zero otherwise.
382 unsigned int vss_repos(void)
384 return mmd->new_vss_status_flags & VSS_REPOS;
388 * Check if the vss is currently paused.
390 * \return Greater than zero if paused, zero otherwise.
393 unsigned int vss_paused(void)
395 return !(mmd->new_vss_status_flags & VSS_NEXT)
396 && !(mmd->new_vss_status_flags & VSS_PLAYING);
400 * Check if the vss is currently stopped.
402 * \return Greater than zero if paused, zero otherwise.
405 unsigned int vss_stopped(void)
407 return (mmd->new_vss_status_flags & VSS_NEXT)
408 && !(mmd->new_vss_status_flags & VSS_PLAYING);
411 static int chk_barrier(const char *bname, const struct timeval *barrier,
412 struct timeval *diff, int print_log)
416 if (tv_diff(now, barrier, diff) > 0)
420 PARA_DEBUG_LOG("%s barrier: %lims left\n", bname, ms);
425 * != NULL: timeout for next chunk
426 * NULL: nothing to do
428 static struct timeval *vss_compute_timeout(struct vss_task *vsst)
430 static struct timeval the_timeout;
431 struct timeval next_chunk;
433 if (vss_next() && vsst->map) {
434 /* only sleep a bit, nec*/
435 the_timeout.tv_sec = 0;
436 the_timeout.tv_usec = 100;
439 if (chk_barrier("autoplay_delay", &vsst->autoplay_barrier,
440 &the_timeout, 1) < 0)
442 if (chk_barrier("eof", &vsst->eof_barrier, &the_timeout, 1) < 0)
444 if (chk_barrier("data send", &vsst->data_send_barrier,
445 &the_timeout, 1) < 0)
447 if (!vss_playing() || !vsst->map)
449 compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
450 &mmd->stream_start, &next_chunk);
451 if (chk_barrier("chunk", &next_chunk, &the_timeout, 0) >= 0) {
452 /* chunk is due or bof */
453 the_timeout.tv_sec = 0;
454 the_timeout.tv_usec = 0;
457 /* compute min of current timeout and next slice time */
458 compute_slice_timeout(&the_timeout);
462 static void vss_eof(struct vss_task *vsst)
465 mmd->stream_start = *now;
468 if (mmd->new_vss_status_flags & VSS_NOMORE)
469 mmd->new_vss_status_flags = VSS_NEXT;
470 tv_add(&mmd->afd.afhi.eof_tv, now, &vsst->eof_barrier);
471 para_munmap(vsst->map, mmd->size);
473 mmd->chunks_sent = 0;
475 mmd->afd.afhi.seconds_total = 0;
476 mmd->afd.afhi.chunk_tv.tv_sec = 0;
477 mmd->afd.afhi.chunk_tv.tv_usec = 0;
478 free(mmd->afd.afhi.chunk_table);
479 mmd->afd.afhi.chunk_table = NULL;
480 free(mmd->afd.afhi.info_string);
481 mmd->afd.afhi.info_string = make_message("%s:\n%s:\n%s:\n", status_item_list[SI_AUDIO_FILE_INFO],
482 status_item_list[SI_TAGINFO1], status_item_list[SI_TAGINFO2]);
483 make_empty_status_items(mmd->afd.verbose_ls_output);
490 * Get the list of all supported audio formats.
492 * \return Aa space separated list of all supported audio formats
493 * It is not allocated at runtime, i.e. there is no need to free
494 * the returned string in the caller.
496 const char *supported_audio_formats(void)
498 return SUPPORTED_AUDIO_FORMATS;
501 static int need_to_request_new_audio_file(struct vss_task *vsst)
505 if (vsst->map) /* have audio file */
507 if (!vss_playing()) /* don't need one */
509 if (mmd->new_vss_status_flags & VSS_NOMORE)
511 if (vsst->afsss == AFS_SOCKET_AFD_PENDING) /* already requested one */
513 if (chk_barrier("autoplay_delay", &vsst->autoplay_barrier,
522 * Compute the timeout for para_server's main select-loop.
524 * This function gets called from para_server to determine the timeout value
525 * for its main select loop.
527 * \param s Pointer to the server scheduler.
528 * \param t Pointer to the vss task structure.
530 * Before the timeout is computed, the current vss status flags are evaluated
531 * and acted upon by calling appropriate functions from the lower layers.
532 * Possible actions include
534 * - request a new audio file from afs,
535 * - shutdown of all senders (stop/pause command),
536 * - reposition the stream (ff/jmp command).
538 static void vss_pre_select(struct sched *s, struct task *t)
541 struct timeval *tv, diff;
542 struct vss_task *vsst = container_of(t, struct vss_task, task);
544 if (!vsst->map || vss_next() || vss_paused() || vss_repos()) {
545 struct fec_client *fc, *tmp;
546 for (i = 0; senders[i].name; i++)
547 if (senders[i].shutdown_clients)
548 senders[i].shutdown_clients();
549 list_for_each_entry_safe(fc, tmp, &fec_client_list, node)
550 fc->first_stream_chunk = -1;
554 else if (vss_paused()) {
555 if (mmd->chunks_sent)
556 tv_add(&mmd->afd.afhi.eof_tv, now, &vsst->eof_barrier);
557 mmd->chunks_sent = 0;
558 } else if (vss_repos()) {
559 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
560 tv_add(&mmd->afd.afhi.eof_tv, now, &vsst->eof_barrier);
561 mmd->chunks_sent = 0;
562 mmd->current_chunk = mmd->repos_request;
563 mmd->new_vss_status_flags &= ~VSS_REPOS;
565 if (need_to_request_new_audio_file(vsst)) {
566 PARA_DEBUG_LOG("ready and playing, but no audio file\n");
567 para_fd_set(vsst->afs_socket, &s->wfds, &s->max_fileno);
568 vsst->afsss = AFS_SOCKET_CHECK_FOR_WRITE;
570 para_fd_set(vsst->afs_socket, &s->rfds, &s->max_fileno);
571 for (i = 0; senders[i].name; i++) {
572 if (!senders[i].pre_select)
574 senders[i].pre_select(&s->max_fileno, &s->rfds, &s->wfds);
576 tv = vss_compute_timeout(vsst);
577 if (tv && tv_diff(tv, &s->timeout, &diff) < 0)
581 static int recv_afs_msg(int afs_socket, int *fd, uint32_t *code, uint32_t *data)
583 char control[255], buf[8];
584 struct msghdr msg = {.msg_iov = NULL};
585 struct cmsghdr *cmsg;
591 iov.iov_len = sizeof(buf);
594 msg.msg_control = control;
595 msg.msg_controllen = sizeof(control);
596 memset(buf, 0, sizeof(buf));
597 ret = recvmsg(afs_socket, &msg, 0);
599 return -ERRNO_TO_PARA_ERROR(errno);
600 if (iov.iov_len != sizeof(buf))
601 return -E_AFS_SHORT_READ;
602 *code = *(uint32_t*)buf;
603 *data = *(uint32_t*)(buf + 4);
604 for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
605 if (cmsg->cmsg_level != SOL_SOCKET
606 || cmsg->cmsg_type != SCM_RIGHTS)
608 if ((cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int) != 1)
610 *fd = *(int *)CMSG_DATA(cmsg);
615 static void recv_afs_result(struct vss_task *vsst)
617 int ret, passed_fd, shmid;
618 uint32_t afs_code = 0, afs_data = 0;
621 vsst->afsss = AFS_SOCKET_READY;
622 mmd->afd.afhi.chunk_table = NULL;
623 ret = recv_afs_msg(vsst->afs_socket, &passed_fd, &afs_code, &afs_data);
626 PARA_DEBUG_LOG("fd: %d, code: %u, shmid: %u\n", passed_fd, afs_code,
629 if (afs_code != NEXT_AUDIO_FILE)
634 ret = load_afd(shmid, &mmd->afd);
638 ret = fstat(passed_fd, &statbuf);
640 PARA_ERROR_LOG("fstat error:\n");
641 ret = -ERRNO_TO_PARA_ERROR(errno);
644 mmd->size = statbuf.st_size;
645 mmd->mtime = statbuf.st_mtime;
646 ret = para_mmap(mmd->size, PROT_READ, MAP_PRIVATE, passed_fd,
651 mmd->chunks_sent = 0;
652 mmd->current_chunk = 0;
656 mmd->new_vss_status_flags &= (~VSS_NEXT);
657 afh_get_header(&mmd->afd.afhi, vsst->map, &vsst->header_buf,
661 free(mmd->afd.afhi.chunk_table);
664 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
665 mmd->new_vss_status_flags = VSS_NEXT;
669 * Main sending function.
671 * This function gets called from vss_post_select(). It checks whether the next
672 * chunk of data should be pushed out. It obtains a pointer to the data to be
673 * sent out as well as its length from mmd->afd.afhi. This information is then
674 * passed to each supported sender's send() function as well as to the send()
675 * functions of each registered fec client.
677 static void vss_send(struct vss_task *vsst)
681 struct fec_client *fc, *tmp_fc;
683 if (!vsst->map || !vss_playing())
685 if (chk_barrier("eof", &vsst->eof_barrier, &due, 1) < 0)
687 if (chk_barrier("data send", &vsst->data_send_barrier,
690 if (mmd->current_chunk >= mmd->afd.afhi.chunks_total) { /* eof */
691 mmd->new_vss_status_flags |= VSS_NEXT;
694 if (!mmd->chunks_sent) {
696 mmd->stream_start = *now;
697 tv_scale(mmd->current_chunk, &mmd->afd.afhi.chunk_tv, &tmp);
698 mmd->offset = tv2ms(&tmp);
701 compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
702 &mmd->stream_start, &due);
703 if (tv_diff(&due, now, NULL) <= 0) {
707 * We call the send function also in case of empty chunks as
708 * they might have still some data queued which can be sent in
711 afh_get_chunk(mmd->current_chunk, &mmd->afd.afhi, vsst->map,
713 for (i = 0; senders[i].name; i++) {
714 if (!senders[i].send)
716 senders[i].send(mmd->current_chunk, mmd->chunks_sent,
717 buf, len, vsst->header_buf, vsst->header_len);
720 list_for_each_entry_safe(fc, tmp_fc, &fec_client_list, node) {
721 if (!next_slice_is_due(fc, NULL))
723 compute_next_fec_slice(fc, vsst);
724 PARA_DEBUG_LOG("sending %d:%d (%zu bytes)\n", fc->group.num,
725 fc->slice.num, fc->slice.bytes);
726 fc->fcp->send((char *)fc->enc_buf,
727 fc->slice.bytes + FEC_HEADER_SIZE,
728 fc->fcp->private_data);
731 mmd->new_vss_status_flags |= VSS_PLAYING;
733 mmd->current_chunk++;
736 static void vss_post_select(struct sched *s, struct task *t)
739 struct vss_task *vsst = container_of(t, struct vss_task, task);
741 if (mmd->sender_cmd_data.cmd_num >= 0) {
742 int num = mmd->sender_cmd_data.cmd_num,
743 sender_num = mmd->sender_cmd_data.sender_num;
745 if (senders[sender_num].client_cmds[num])
746 senders[sender_num].client_cmds[num](&mmd->sender_cmd_data);
747 mmd->sender_cmd_data.cmd_num = -1;
749 if (vsst->afsss != AFS_SOCKET_CHECK_FOR_WRITE) {
750 if (FD_ISSET(vsst->afs_socket, &s->rfds))
751 recv_afs_result(vsst);
752 } else if (FD_ISSET(vsst->afs_socket, &s->wfds)) {
753 PARA_NOTICE_LOG("requesting new fd from afs\n");
754 ret = send_buffer(vsst->afs_socket, "new");
755 vsst->afsss = AFS_SOCKET_AFD_PENDING;
757 for (i = 0; senders[i].name; i++) {
758 if (!senders[i].post_select)
760 senders[i].post_select(&s->rfds, &s->wfds);
762 if ((vss_playing() && !(mmd->vss_status_flags & VSS_PLAYING)) ||
763 (vss_next() && vss_playing()))
764 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
769 * Initialize the virtual streaming system task.
771 * \param afs_socket The fd for communication with afs.
773 * This also initializes all supported senders and starts streaming
774 * if the --autoplay command line flag was given.
776 void init_vss_task(int afs_socket)
778 static struct vss_task vss_task_struct, *vsst = &vss_task_struct;
780 char *hn = para_hostname(), *home = para_homedir();
781 long unsigned announce_time = conf.announce_time_arg > 0?
782 conf.announce_time_arg : 300,
783 autoplay_delay = conf.autoplay_delay_arg > 0?
784 conf.autoplay_delay_arg : 0;
786 vsst->afs_socket = afs_socket;
787 vsst->task.pre_select = vss_pre_select;
788 vsst->task.post_select = vss_post_select;
789 ms2tv(announce_time, &vsst->announce_tv);
790 PARA_INFO_LOG("announce timeval: %lums\n", tv2ms(&vsst->announce_tv));
791 for (i = 0; senders[i].name; i++) {
792 PARA_NOTICE_LOG("initializing %s sender\n", senders[i].name);
793 senders[i].init(&senders[i]);
797 mmd->sender_cmd_data.cmd_num = -1;
798 make_empty_status_items(mmd->afd.verbose_ls_output);
799 if (conf.autoplay_given) {
801 mmd->vss_status_flags |= VSS_PLAYING;
802 mmd->new_vss_status_flags |= VSS_PLAYING;
803 ms2tv(autoplay_delay, &tmp);
804 tv_add(now, &tmp, &vsst->autoplay_barrier);
805 tv_add(&vsst->autoplay_barrier, &vsst->announce_tv,
806 &vsst->data_send_barrier);
808 INIT_LIST_HEAD(&fec_client_list);
809 register_task(&vsst->task);