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 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;
152 if (chunk_num >= mmd->afd.afhi.chunks_total)
154 afh_get_chunk(chunk_num, &mmd->afd.afhi, vsst->map, &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] = (const unsigned char *)start_buf
183 + i * fc->slice.bytes;
185 if (start_buf + k * fc->slice.bytes > vsst->map + mmd->size) {
186 /* can not use last slice as it goes beyond the map */
187 if (fc->extra_src_buf_size < fc->slice.bytes)
188 fc->extra_src_buf = para_realloc(fc->extra_src_buf, fc->slice.bytes);
189 memcpy(fc->extra_src_buf, start_buf + (k - 1) * fc->slice.bytes,
191 memset(fc->extra_src_buf + last_payload_size, 0,
192 fc->slice.bytes - last_payload_size);
193 fc->src_data[k - 1] = fc->extra_src_buf;
199 * Write a fec header to a buffer.
201 * \param buf The buffer to write to.
202 * \param h The fec header to write.
204 static void write_fec_header(struct fec_client *fc)
206 char *buf = (char *)fc->enc_buf;
208 write_u32(buf, FEC_MAGIC);
210 write_u8(buf + 4, fc->fcp->slices_per_group);
211 write_u8(buf + 5, fc->fcp->data_slices_per_group);
212 write_u32(buf + 6, (uint32_t)0); /* audio header len */
214 write_u32(buf + 10, fc->group.num);
215 write_u32(buf + 14, fc->group.bytes);
217 write_u8(buf + 18, fc->slice.num);
218 write_u16(buf + 20, fc->slice.bytes);
219 memset(buf + 22, 0, 11);
223 * Return a buffer that marks the end of the stream.
225 * \return The length of the eof buffer.
227 * This is used for (multicast) udp streaming where closing the socket on the
228 * sender might not give rise to an eof condition at the peer.
230 size_t vss_get_fec_eof_packet(const char **buf)
232 static const char fec_eof_packet[FEC_HEADER_SIZE] =
233 "\xec\x0d\xcc\xfe\0\0\0\0"
237 *buf = fec_eof_packet;
238 return FEC_HEADER_SIZE;
241 static void compute_next_fec_slice(struct fec_client *fc, struct vss_task *vsst)
243 if (fc->first_stream_chunk < 0) {
244 fc->stream_start = *now;
245 fc->first_stream_chunk = mmd->current_chunk;
246 fc->group.first_chunk = mmd->current_chunk;
248 setup_fec_group(fc, vsst);
249 } else if (fc->slice.num == fc->fcp->slices_per_group) {
250 fc->group.first_chunk += fc->group.num_chunks;
251 setup_fec_group(fc, vsst);
254 if (fc->enc_buf_size < fc->slice.bytes + FEC_HEADER_SIZE) {
255 fc->enc_buf_size = fc->slice.bytes + FEC_HEADER_SIZE;
256 fc->enc_buf = para_realloc(fc->enc_buf, fc->enc_buf_size);
258 write_fec_header(fc);
259 fec_encode(fc->parms, fc->src_data, fc->enc_buf + FEC_HEADER_SIZE,
260 fc->slice.num, fc->slice.bytes);
264 * Add one entry to the list of active fec clients.
266 * \param fcp Describes the fec parameters to be used for this client.
267 * \param result An opaque pointer that must be used by remove the client later.
271 int vss_add_fec_client(struct fec_client_parms *fcp, struct fec_client **result)
274 struct fec_client *fc;
276 if (fcp->max_slice_bytes < FEC_HEADER_SIZE + fcp->data_slices_per_group)
277 return -ERRNO_TO_PARA_ERROR(EINVAL);
278 fc = para_calloc(sizeof(*fc));
280 ret = fec_new(fcp->data_slices_per_group, fcp->slices_per_group,
284 fc->first_stream_chunk = -1; /* stream not yet started */
285 fc->src_data = para_malloc(fc->fcp->slices_per_group * sizeof(char *));
286 para_list_add(&fc->node, &fec_client_list);
297 * Remove one entry from the list of active fec clients.
299 * \param result The client to be removed.
301 void vss_del_fec_client(struct fec_client *fc)
306 free(fc->extra_src_buf);
312 * Compute if/when next slice is due. If it isn't due yet and \a diff is
313 * not \p Null, compute the time difference next - now, where
315 * next = stream_start + (first_group_chunk - first_stream_chunk)
316 * * chunk_time + slice_num * slice_time
318 static int next_slice_is_due(struct fec_client *fc, struct timeval *diff)
320 struct timeval tmp, next;
323 if (fc->first_stream_chunk < 0)
325 tv_scale(fc->slice.num, &fc->group.slice_duration, &tmp);
326 tv_add(&tmp, &fc->group.start, &next);
327 ret = tv_diff(&next, now, diff);
328 return ret < 0? 1 : 0;
331 static void compute_slice_timeout(struct timeval *timeout)
333 struct fec_client *fc;
335 assert(vss_playing());
336 list_for_each_entry(fc, &fec_client_list, node) {
338 int ret = next_slice_is_due(fc, &diff);
340 // PARA_NOTICE_LOG("diff: %lu, ret: %d\n", tv2ms(&diff), ret);
343 timeout->tv_usec = 0;
346 /* timeout = min(timeout, diff) */
347 if (tv_diff(&diff, timeout, NULL) < 0)
352 PARA_NOTICE_LOG("slice timeout: %lu:%lu\n", (long unsigned)timeout->tv_sec, (long unsigned)timeout->tv_usec);
356 * Check if vss status flag \a P (playing) is set.
358 * \return Greater than zero if playing, zero otherwise.
361 unsigned int vss_playing(void)
363 return mmd->new_vss_status_flags & VSS_PLAYING;
367 * Check if the \a N (next) status flag is set.
369 * \return Greater than zero if set, zero if not.
372 unsigned int vss_next(void)
374 return mmd->new_vss_status_flags & VSS_NEXT;
378 * Check if a reposition request is pending.
380 * \return Greater than zero if true, zero otherwise.
383 unsigned int vss_repos(void)
385 return mmd->new_vss_status_flags & VSS_REPOS;
389 * Check if the vss is currently paused.
391 * \return Greater than zero if paused, zero otherwise.
394 unsigned int vss_paused(void)
396 return !(mmd->new_vss_status_flags & VSS_NEXT)
397 && !(mmd->new_vss_status_flags & VSS_PLAYING);
401 * Check if the vss is currently stopped.
403 * \return Greater than zero if paused, zero otherwise.
406 unsigned int vss_stopped(void)
408 return (mmd->new_vss_status_flags & VSS_NEXT)
409 && !(mmd->new_vss_status_flags & VSS_PLAYING);
412 static int chk_barrier(const char *bname, const struct timeval *barrier,
413 struct timeval *diff, int print_log)
417 if (tv_diff(now, barrier, diff) > 0)
421 PARA_DEBUG_LOG("%s barrier: %lims left\n", bname, ms);
426 * != NULL: timeout for next chunk
427 * NULL: nothing to do
429 static struct timeval *vss_compute_timeout(struct vss_task *vsst)
431 static struct timeval the_timeout;
432 struct timeval next_chunk;
434 if (vss_next() && vsst->map) {
435 /* only sleep a bit, nec*/
436 the_timeout.tv_sec = 0;
437 the_timeout.tv_usec = 100;
440 if (chk_barrier("autoplay_delay", &vsst->autoplay_barrier,
441 &the_timeout, 1) < 0)
443 if (chk_barrier("eof", &vsst->eof_barrier, &the_timeout, 1) < 0)
445 if (chk_barrier("data send", &vsst->data_send_barrier,
446 &the_timeout, 1) < 0)
448 if (!vss_playing() || !vsst->map)
450 compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
451 &mmd->stream_start, &next_chunk);
452 if (chk_barrier("chunk", &next_chunk, &the_timeout, 0) >= 0) {
453 /* chunk is due or bof */
454 the_timeout.tv_sec = 0;
455 the_timeout.tv_usec = 0;
458 /* compute min of current timeout and next slice time */
459 compute_slice_timeout(&the_timeout);
463 static void vss_eof(struct vss_task *vsst)
466 mmd->stream_start = *now;
469 if (mmd->new_vss_status_flags & VSS_NOMORE)
470 mmd->new_vss_status_flags = VSS_NEXT;
471 tv_add(&mmd->afd.afhi.eof_tv, now, &vsst->eof_barrier);
472 para_munmap(vsst->map, mmd->size);
474 mmd->chunks_sent = 0;
476 mmd->afd.afhi.seconds_total = 0;
477 mmd->afd.afhi.chunk_tv.tv_sec = 0;
478 mmd->afd.afhi.chunk_tv.tv_usec = 0;
479 free(mmd->afd.afhi.chunk_table);
480 mmd->afd.afhi.chunk_table = NULL;
481 free(mmd->afd.afhi.info_string);
482 mmd->afd.afhi.info_string = make_message("%s:\n%s:\n%s:\n", status_item_list[SI_AUDIO_FILE_INFO],
483 status_item_list[SI_TAGINFO1], status_item_list[SI_TAGINFO2]);
484 make_empty_status_items(mmd->afd.verbose_ls_output);
491 * Get the list of all supported audio formats.
493 * \return Aa space separated list of all supported audio formats
494 * It is not allocated at runtime, i.e. there is no need to free
495 * the returned string in the caller.
497 const char *supported_audio_formats(void)
499 return SUPPORTED_AUDIO_FORMATS;
502 static int need_to_request_new_audio_file(struct vss_task *vsst)
506 if (vsst->map) /* have audio file */
508 if (!vss_playing()) /* don't need one */
510 if (mmd->new_vss_status_flags & VSS_NOMORE)
512 if (vsst->afsss == AFS_SOCKET_AFD_PENDING) /* already requested one */
514 if (chk_barrier("autoplay_delay", &vsst->autoplay_barrier,
523 * Compute the timeout for para_server's main select-loop.
525 * This function gets called from para_server to determine the timeout value
526 * for its main select loop.
528 * \param s Pointer to the server scheduler.
529 * \param t Pointer to the vss task structure.
531 * Before the timeout is computed, the current vss status flags are evaluated
532 * and acted upon by calling appropriate functions from the lower layers.
533 * Possible actions include
535 * - request a new audio file from afs,
536 * - shutdown of all senders (stop/pause command),
537 * - reposition the stream (ff/jmp command).
539 static void vss_pre_select(struct sched *s, struct task *t)
542 struct timeval *tv, diff;
543 struct vss_task *vsst = container_of(t, struct vss_task, task);
545 if (!vsst->map || vss_next() || vss_paused() || vss_repos()) {
546 struct fec_client *fc, *tmp;
547 for (i = 0; senders[i].name; i++)
548 if (senders[i].shutdown_clients)
549 senders[i].shutdown_clients();
550 list_for_each_entry_safe(fc, tmp, &fec_client_list, node)
551 fc->first_stream_chunk = -1;
555 else if (vss_paused()) {
556 if (mmd->chunks_sent)
557 tv_add(&mmd->afd.afhi.eof_tv, now, &vsst->eof_barrier);
558 mmd->chunks_sent = 0;
559 } else if (vss_repos()) {
560 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
561 tv_add(&mmd->afd.afhi.eof_tv, now, &vsst->eof_barrier);
562 mmd->chunks_sent = 0;
563 mmd->current_chunk = mmd->repos_request;
564 mmd->new_vss_status_flags &= ~VSS_REPOS;
566 if (need_to_request_new_audio_file(vsst)) {
567 PARA_DEBUG_LOG("ready and playing, but no audio file\n");
568 para_fd_set(vsst->afs_socket, &s->wfds, &s->max_fileno);
569 vsst->afsss = AFS_SOCKET_CHECK_FOR_WRITE;
571 para_fd_set(vsst->afs_socket, &s->rfds, &s->max_fileno);
572 for (i = 0; senders[i].name; i++) {
573 if (!senders[i].pre_select)
575 senders[i].pre_select(&s->max_fileno, &s->rfds, &s->wfds);
577 tv = vss_compute_timeout(vsst);
578 if (tv && tv_diff(tv, &s->timeout, &diff) < 0)
582 static int recv_afs_msg(int afs_socket, int *fd, uint32_t *code, uint32_t *data)
584 char control[255], buf[8];
585 struct msghdr msg = {.msg_iov = NULL};
586 struct cmsghdr *cmsg;
592 iov.iov_len = sizeof(buf);
595 msg.msg_control = control;
596 msg.msg_controllen = sizeof(control);
597 memset(buf, 0, sizeof(buf));
598 ret = recvmsg(afs_socket, &msg, 0);
600 return -ERRNO_TO_PARA_ERROR(errno);
601 if (iov.iov_len != sizeof(buf))
602 return -E_AFS_SHORT_READ;
603 *code = *(uint32_t*)buf;
604 *data = *(uint32_t*)(buf + 4);
605 for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
606 if (cmsg->cmsg_level != SOL_SOCKET
607 || cmsg->cmsg_type != SCM_RIGHTS)
609 if ((cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int) != 1)
611 *fd = *(int *)CMSG_DATA(cmsg);
616 static void recv_afs_result(struct vss_task *vsst)
618 int ret, passed_fd, shmid;
619 uint32_t afs_code = 0, afs_data = 0;
622 vsst->afsss = AFS_SOCKET_READY;
623 mmd->afd.afhi.chunk_table = NULL;
624 ret = recv_afs_msg(vsst->afs_socket, &passed_fd, &afs_code, &afs_data);
627 PARA_DEBUG_LOG("fd: %d, code: %u, shmid: %u\n", passed_fd, afs_code,
630 if (afs_code != NEXT_AUDIO_FILE)
635 ret = load_afd(shmid, &mmd->afd);
639 ret = fstat(passed_fd, &statbuf);
641 PARA_ERROR_LOG("fstat error:\n");
642 ret = -ERRNO_TO_PARA_ERROR(errno);
645 mmd->size = statbuf.st_size;
646 mmd->mtime = statbuf.st_mtime;
647 ret = para_mmap(mmd->size, PROT_READ, MAP_PRIVATE, passed_fd,
652 mmd->chunks_sent = 0;
653 mmd->current_chunk = 0;
657 mmd->new_vss_status_flags &= (~VSS_NEXT);
658 afh_get_header(&mmd->afd.afhi, vsst->map, &vsst->header_buf,
662 free(mmd->afd.afhi.chunk_table);
665 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
666 mmd->new_vss_status_flags = VSS_NEXT;
670 * Main sending function.
672 * This function gets called from vss_post_select(). It checks whether the next
673 * chunk of data should be pushed out. It obtains a pointer to the data to be
674 * sent out as well as its length from mmd->afd.afhi. This information is then
675 * passed to each supported sender's send() function as well as to the send()
676 * functions of each registered fec client.
678 static void vss_send(struct vss_task *vsst)
682 struct fec_client *fc, *tmp_fc;
684 if (!vsst->map || !vss_playing())
686 if (chk_barrier("eof", &vsst->eof_barrier, &due, 1) < 0)
688 if (chk_barrier("data send", &vsst->data_send_barrier,
691 if (mmd->current_chunk >= mmd->afd.afhi.chunks_total) { /* eof */
692 mmd->new_vss_status_flags |= VSS_NEXT;
695 if (!mmd->chunks_sent) {
697 mmd->stream_start = *now;
698 tv_scale(mmd->current_chunk, &mmd->afd.afhi.chunk_tv, &tmp);
699 mmd->offset = tv2ms(&tmp);
702 compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
703 &mmd->stream_start, &due);
704 if (tv_diff(&due, now, NULL) <= 0) {
708 * We call the send function also in case of empty chunks as
709 * they might have still some data queued which can be sent in
712 afh_get_chunk(mmd->current_chunk, &mmd->afd.afhi, vsst->map,
714 for (i = 0; senders[i].name; i++) {
715 if (!senders[i].send)
717 senders[i].send(mmd->current_chunk, mmd->chunks_sent,
718 buf, len, vsst->header_buf, vsst->header_len);
721 list_for_each_entry_safe(fc, tmp_fc, &fec_client_list, node) {
722 if (!next_slice_is_due(fc, NULL))
724 compute_next_fec_slice(fc, vsst);
725 PARA_DEBUG_LOG("sending %d:%d (%zu bytes)\n", fc->group.num,
726 fc->slice.num, fc->slice.bytes);
727 fc->fcp->send((char *)fc->enc_buf,
728 fc->slice.bytes + FEC_HEADER_SIZE,
729 fc->fcp->private_data);
732 mmd->new_vss_status_flags |= VSS_PLAYING;
734 mmd->current_chunk++;
737 static void vss_post_select(struct sched *s, struct task *t)
740 struct vss_task *vsst = container_of(t, struct vss_task, task);
742 if (mmd->sender_cmd_data.cmd_num >= 0) {
743 int num = mmd->sender_cmd_data.cmd_num,
744 sender_num = mmd->sender_cmd_data.sender_num;
746 if (senders[sender_num].client_cmds[num])
747 senders[sender_num].client_cmds[num](&mmd->sender_cmd_data);
748 mmd->sender_cmd_data.cmd_num = -1;
750 if (vsst->afsss != AFS_SOCKET_CHECK_FOR_WRITE) {
751 if (FD_ISSET(vsst->afs_socket, &s->rfds))
752 recv_afs_result(vsst);
753 } else if (FD_ISSET(vsst->afs_socket, &s->wfds)) {
754 PARA_NOTICE_LOG("requesting new fd from afs\n");
755 ret = send_buffer(vsst->afs_socket, "new");
756 vsst->afsss = AFS_SOCKET_AFD_PENDING;
758 for (i = 0; senders[i].name; i++) {
759 if (!senders[i].post_select)
761 senders[i].post_select(&s->rfds, &s->wfds);
763 if ((vss_playing() && !(mmd->vss_status_flags & VSS_PLAYING)) ||
764 (vss_next() && vss_playing()))
765 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
770 * Initialize the virtual streaming system task.
772 * \param afs_socket The fd for communication with afs.
774 * This also initializes all supported senders and starts streaming
775 * if the --autoplay command line flag was given.
777 void init_vss_task(int afs_socket)
779 static struct vss_task vss_task_struct, *vsst = &vss_task_struct;
781 char *hn = para_hostname(), *home = para_homedir();
782 long unsigned announce_time = conf.announce_time_arg > 0?
783 conf.announce_time_arg : 300,
784 autoplay_delay = conf.autoplay_delay_arg > 0?
785 conf.autoplay_delay_arg : 0;
787 vsst->afs_socket = afs_socket;
788 vsst->task.pre_select = vss_pre_select;
789 vsst->task.post_select = vss_post_select;
790 ms2tv(announce_time, &vsst->announce_tv);
791 PARA_INFO_LOG("announce timeval: %lums\n", tv2ms(&vsst->announce_tv));
792 for (i = 0; senders[i].name; i++) {
793 PARA_NOTICE_LOG("initializing %s sender\n", senders[i].name);
794 senders[i].init(&senders[i]);
798 mmd->sender_cmd_data.cmd_num = -1;
799 make_empty_status_items(mmd->afd.verbose_ls_output);
800 if (conf.autoplay_given) {
802 mmd->vss_status_flags |= VSS_PLAYING;
803 mmd->new_vss_status_flags |= VSS_PLAYING;
804 ms2tv(autoplay_delay, &tmp);
805 tv_add(now, &tmp, &vsst->autoplay_barrier);
806 tv_add(&vsst->autoplay_barrier, &vsst->announce_tv,
807 &vsst->data_send_barrier);
809 INIT_LIST_HEAD(&fec_client_list);
810 register_task(&vsst->task);