2 * Copyright (C) 1997-2010 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
20 #include "portable_io.h"
27 #include "server.cmdline.h"
35 extern struct misc_meta_data *mmd;
37 extern void dccp_send_init(struct sender *);
38 extern void http_send_init(struct sender *);
39 extern void udp_send_init(struct sender *);
41 /** The list of supported senders. */
42 struct sender senders[] = {
45 .init = http_send_init,
49 .init = dccp_send_init,
53 .init = udp_send_init,
60 /** The possible states of the afs socket. */
61 enum afs_socket_status {
62 /** Socket is inactive. */
64 /** Socket fd was included in the write fd set for select(). */
65 AFS_SOCKET_CHECK_FOR_WRITE,
66 /** vss wrote a request to the socket and waits for reply from afs. */
67 AFS_SOCKET_AFD_PENDING
70 /** The task structure for the virtual streaming system. */
72 /** Copied from the -announce_time command line option. */
73 struct timeval announce_tv;
74 /** End of the announcing interval. */
75 struct timeval data_send_barrier;
76 /** End of the EOF interval. */
77 struct timeval eof_barrier;
78 /** Only used if --autoplay_delay was given. */
79 struct timeval autoplay_barrier;
80 /** Used for afs-server communication. */
82 /** The current state of \a afs_socket. */
83 enum afs_socket_status afsss;
84 /** The memory mapped audio file. */
86 /** Used by the scheduler. */
88 /** Pointer to the header of the mapped audio file. */
89 const char *header_buf;
90 /** Length of the audio file header. */
92 /** Time between audio file headers are sent. */
93 struct timeval header_interval;
97 * The list of currently connected fec clients.
99 * Senders may use \ref vss_add_fec_client() to add entries to the list.
101 static struct list_head fec_client_list;
104 * Data associated with one FEC group.
106 * A FEC group consists of a fixed number of slices and this number is given by
107 * the \a slices_per_group parameter of struct \ref fec_client_parms. Each FEC
108 * group contains a number of chunks of the current audio file.
110 * FEC slices directly correspond to the data packages sent by the paraslash
111 * senders that use FEC. Each slice is identified by its group number and its
112 * number within the group. All slices have the same size, but the last slice
113 * of the group may not be filled entirely.
116 /** The number of the FEC group. */
118 /** Number of bytes in this group. */
120 /** The first chunk of the current audio file belonging to the group. */
121 uint32_t first_chunk;
122 /** The number of chunks contained in this group. */
124 /** When the first chunk was sent. */
125 struct timeval start;
126 /** The duration of the full group. */
127 struct timeval duration;
128 /** The group duration divided by the number of slices. */
129 struct timeval slice_duration;
130 /** Group contains the audio file header that occupies that many slices. */
131 uint8_t num_header_slices;
134 enum fec_client_state {
135 FEC_STATE_NONE = 0, /**< not initialized and not enabled */
136 FEC_STATE_DISABLED, /**< temporarily disabled */
137 FEC_STATE_READY_TO_RUN /**< initialized and enabled */
141 * Describes one connected FEC client.
144 /** Current state of the client */
145 enum fec_client_state state;
146 /** The connected sender client (transport layer). */
147 struct sender_client *sc;
148 /** Parameters requested by the client. */
149 struct fec_client_parms *fcp;
150 /** Used by the core FEC code. */
151 struct fec_parms *parms;
152 /** The position of this client in the fec client list. */
153 struct list_head node;
154 /** When the first slice for this client was sent. */
155 struct timeval stream_start;
156 /** The first chunk sent to this FEC client. */
157 int first_stream_chunk;
158 /** Describes the current group. */
159 struct fec_group group;
160 /** The current slice. */
161 uint8_t current_slice_num;
162 /** The data to be FEC-encoded (point to a region within the mapped audio file). */
163 const unsigned char **src_data;
164 /** Last time an audio header was sent. */
165 struct timeval next_header_time;
166 /** Used for the last source pointer of an audio file. */
167 unsigned char *extra_src_buf;
168 /** Extra slices needed to store largest chunk + header. */
169 int num_extra_slices;
170 /** Contains the FEC-encoded data. */
171 unsigned char *enc_buf;
172 /** Maximal packet size. */
177 * Get the chunk time of the current audio file.
179 * \return A pointer to a struct containing the chunk time, or NULL,
180 * if currently no audio file is selected.
182 struct timeval *vss_chunk_time(void)
184 if (mmd->afd.afhi.chunk_tv.tv_sec == 0 &&
185 mmd->afd.afhi.chunk_tv.tv_usec == 0)
187 return &mmd->afd.afhi.chunk_tv;
191 * Write a fec header to a buffer.
193 * \param buf The buffer to write to.
194 * \param h The fec header to write.
196 static void write_fec_header(struct fec_client *fc, struct vss_task *vsst)
198 char *buf = (char *)fc->enc_buf;
199 struct fec_group *g = &fc->group;
200 struct fec_client_parms *p = fc->fcp;
202 write_u32(buf, FEC_MAGIC);
204 write_u8(buf + 4, p->slices_per_group + fc->num_extra_slices);
205 write_u8(buf + 5, p->data_slices_per_group + fc->num_extra_slices);
206 write_u32(buf + 6, g->num_header_slices? vsst->header_len : 0);
208 write_u32(buf + 10, g->num);
209 write_u32(buf + 14, g->bytes);
211 write_u8(buf + 18, fc->current_slice_num);
212 write_u16(buf + 20, fc->mps - FEC_HEADER_SIZE);
213 write_u8(buf + 22, g->first_chunk? 0 : 1);
214 write_u8(buf + 23, vsst->header_len? 1 : 0);
215 memset(buf + 24, 0, 7);
218 static bool need_audio_header(struct fec_client *fc, struct vss_task *vsst)
220 if (!mmd->current_chunk) {
221 tv_add(now, &vsst->header_interval, &fc->next_header_time);
224 if (!vsst->header_buf)
226 if (vsst->header_len == 0)
228 if (fc->group.num && tv_diff(&fc->next_header_time, now, NULL) > 0)
230 tv_add(now, &vsst->header_interval, &fc->next_header_time);
234 static int num_slices(long unsigned bytes, int mps, int rs)
236 int m = mps - FEC_HEADER_SIZE;
241 ret = DIV_ROUND_UP(bytes, m);
247 /* set group start and group duration */
248 static void set_group_timing(struct fec_client *fc, struct fec_group *g)
250 struct timeval *chunk_tv = vss_chunk_time();
252 tv_scale(g->num_chunks, chunk_tv, &g->duration);
253 tv_divide(fc->fcp->slices_per_group + fc->num_extra_slices,
254 &g->duration, &g->slice_duration);
255 PARA_DEBUG_LOG("durations (group/chunk/slice): %lu/%lu/%lu\n",
256 tv2ms(&g->duration), tv2ms(chunk_tv), tv2ms(&g->slice_duration));
259 static int initialize_fec_client(struct fec_client *fc, struct vss_task *vsst)
262 int hs, ds, rs; /* header/data/redundant slices */
263 struct fec_client_parms *fcp = fc->fcp;
268 * Set the maximum slice size to the Maximum Packet Size if the
269 * transport protocol allows to determine this value. The user
270 * can specify a slice size up to this value.
272 ret = fcp->init_fec(fc->sc);
277 mps = generic_max_transport_msg_size(fc->sc->fd);
278 if (mps <= FEC_HEADER_SIZE)
279 return -ERRNO_TO_PARA_ERROR(EINVAL);
281 rs = fc->fcp->slices_per_group - fc->fcp->data_slices_per_group;
282 ret = num_slices(vsst->header_len, mps, rs);
286 ret = num_slices(mmd->afd.max_chunk_size, mps, rs);
291 if (k < fc->fcp->data_slices_per_group)
292 k = fc->fcp->data_slices_per_group;
294 PARA_CRIT_LOG("hs: %d, ds: %d, rs: %d, k: %d, n: %d\n", hs, ds, rs, k, n);
296 ret = fec_new(k, n, &fc->parms);
299 fc->num_extra_slices = k - fc->fcp->data_slices_per_group;
300 PARA_NOTICE_LOG("fec parms %d:%d:%d (%d extra slices)\n",
301 mps, k, n, fc->num_extra_slices);
302 fc->src_data = para_realloc(fc->src_data, k * sizeof(char *));
303 fc->enc_buf = para_realloc(fc->enc_buf, mps);
304 memset(fc->enc_buf, 0, mps);
305 fc->extra_src_buf = para_realloc(fc->extra_src_buf, mps);
306 memset(fc->extra_src_buf, 0, mps);
309 fc->state = FEC_STATE_READY_TO_RUN;
310 fc->next_header_time.tv_sec = 0;
311 fc->stream_start = *now;
312 fc->first_stream_chunk = mmd->current_chunk;
319 static int setup_next_fec_group(struct fec_client *fc, struct vss_task *vsst)
321 int ret, i, k, n, data_slices;
323 const char *buf, *start_buf;
324 struct fec_group *g = &fc->group;
325 unsigned slice_bytes;
326 uint32_t max_data_size;
328 if (fc->state == FEC_STATE_NONE) {
329 ret = initialize_fec_client(fc, vsst);
332 g->first_chunk = mmd->current_chunk;
338 if (g->first_chunk + g->num_chunks >= mmd->afd.afhi.chunks_total)
341 * Start and duration of this group depend only on the previous
342 * group. Compute the new group start as g->start += g->duration.
345 tv_add(&tmp, &g->duration, &g->start);
346 set_group_timing(fc, g);
347 g->first_chunk += g->num_chunks;
350 slice_bytes = fc->mps - FEC_HEADER_SIZE;
351 PARA_CRIT_LOG("slice_bytes: %d\n", slice_bytes);
352 k = fc->fcp->data_slices_per_group + fc->num_extra_slices;
353 n = fc->fcp->slices_per_group + fc->num_extra_slices;
354 PARA_CRIT_LOG("k: %d, n: %d\n", k, n);
355 if (need_audio_header(fc, vsst)) {
356 ret = num_slices(vsst->header_len, slice_bytes, n - k);
359 g->num_header_slices = ret;
361 g->num_header_slices = 0;
362 afh_get_chunk(g->first_chunk, &mmd->afd.afhi, vsst->map, &start_buf,
364 data_slices = k - g->num_header_slices;
366 max_data_size = slice_bytes * data_slices;
368 for (i = g->first_chunk; i < mmd->afd.afhi.chunks_total; i++) {
369 afh_get_chunk(i, &mmd->afd.afhi, vsst->map, &buf, &len);
370 if (g->bytes + len > max_data_size)
374 g->num_chunks = i - g->first_chunk;
375 assert(g->num_chunks);
376 fc->current_slice_num = 0;
378 set_group_timing(fc, g);
380 /* setup header slices */
381 buf = vsst->header_buf;
382 for (i = 0; i < g->num_header_slices; i++) {
383 fc->src_data[i] = (const unsigned char *)buf;
387 /* setup data slices */
389 for (i = g->num_header_slices; i < k; i++) {
390 if (buf + slice_bytes > vsst->map + mmd->size)
392 * Can not use the memory mapped audio file for this
393 * slice as it goes beyond the map. This slice will not
397 fc->src_data[i] = (const unsigned char *)buf;
401 uint32_t payload_size = vsst->map + mmd->size - buf;
402 memcpy(fc->extra_src_buf, buf, payload_size);
403 fc->src_data[i] = fc->extra_src_buf;
405 /* use arbitrary data for all remaining slices */
408 fc->src_data[i] = (const unsigned char *)buf;
410 PARA_DEBUG_LOG("FEC group %d: %d chunks (%d - %d), "
411 "%d header slices, %d data slices\n",
412 g->num, g->num_chunks, g->first_chunk,
413 g->first_chunk + g->num_chunks - 1,
414 g->num_header_slices, data_slices
419 static int compute_next_fec_slice(struct fec_client *fc, struct vss_task *vsst)
421 if (fc->state == FEC_STATE_NONE || fc->current_slice_num
422 == fc->fcp->slices_per_group + fc->num_extra_slices) {
423 int ret = setup_next_fec_group(fc, vsst);
427 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
428 PARA_ERROR_LOG("FEC client temporarily disabled\n");
429 fc->state = FEC_STATE_DISABLED;
433 write_fec_header(fc, vsst);
434 fec_encode(fc->parms, fc->src_data, fc->enc_buf + FEC_HEADER_SIZE,
435 fc->current_slice_num, fc->mps - FEC_HEADER_SIZE);
440 * Return a buffer that marks the end of the stream.
442 * \param buf Result pointer.
443 * \return The length of the eof buffer.
445 * This is used for (multicast) udp streaming where closing the socket on the
446 * sender might not give rise to an eof condition at the peer.
448 size_t vss_get_fec_eof_packet(const char **buf)
450 static const char fec_eof_packet[FEC_HEADER_SIZE] = FEC_EOF_PACKET;
451 *buf = fec_eof_packet;
452 return FEC_HEADER_SIZE;
456 * Add one entry to the list of active fec clients.
458 * \param sc Generic sender_client data of the transport layer.
459 * \param fcp FEC parameters as supplied by the transport layer.
461 * \return Newly allocated fec_client struct.
463 struct fec_client *vss_add_fec_client(struct sender_client *sc,
464 struct fec_client_parms *fcp)
466 struct fec_client *fc = para_calloc(sizeof(*fc));
470 para_list_add(&fc->node, &fec_client_list);
475 * Remove one entry from the list of active fec clients.
477 * \param fc The client to be removed.
479 void vss_del_fec_client(struct fec_client *fc)
484 free(fc->extra_src_buf);
490 * Compute if/when next slice is due. If it isn't due yet and \a diff is
491 * not \p Null, compute the time difference next - now, where
493 * next = stream_start + (first_group_chunk - first_stream_chunk)
494 * * chunk_time + slice_num * slice_time
496 static int next_slice_is_due(struct fec_client *fc, struct timeval *diff)
498 struct timeval tmp, next;
501 if (fc->state == FEC_STATE_NONE)
503 tv_scale(fc->current_slice_num, &fc->group.slice_duration, &tmp);
504 tv_add(&tmp, &fc->group.start, &next);
505 ret = tv_diff(&next, now, diff);
506 return ret < 0? 1 : 0;
509 static void compute_slice_timeout(struct timeval *timeout)
511 struct fec_client *fc;
513 list_for_each_entry(fc, &fec_client_list, node) {
516 if (fc->state != FEC_STATE_READY_TO_RUN)
518 if (next_slice_is_due(fc, &diff)) {
520 timeout->tv_usec = 0;
523 /* timeout = min(timeout, diff) */
524 if (tv_diff(&diff, timeout, NULL) < 0)
529 static void set_eof_barrier(struct vss_task *vsst)
531 struct fec_client *fc;
532 struct timeval timeout = {1, 0}, *chunk_tv = vss_chunk_time();
536 list_for_each_entry(fc, &fec_client_list, node) {
537 struct timeval group_duration;
539 if (fc->state != FEC_STATE_READY_TO_RUN)
541 tv_scale(fc->group.num_chunks, chunk_tv, &group_duration);
542 if (tv_diff(&timeout, &group_duration, NULL) < 0)
543 timeout = group_duration;
546 tv_add(now, &timeout, &vsst->eof_barrier);
550 * Check if vss status flag \a P (playing) is set.
552 * \return Greater than zero if playing, zero otherwise.
555 unsigned int vss_playing(void)
557 return mmd->new_vss_status_flags & VSS_PLAYING;
561 * Check if the \a N (next) status flag is set.
563 * \return Greater than zero if set, zero if not.
566 unsigned int vss_next(void)
568 return mmd->new_vss_status_flags & VSS_NEXT;
572 * Check if a reposition request is pending.
574 * \return Greater than zero if true, zero otherwise.
577 unsigned int vss_repos(void)
579 return mmd->new_vss_status_flags & VSS_REPOS;
583 * Check if the vss is currently paused.
585 * \return Greater than zero if paused, zero otherwise.
588 unsigned int vss_paused(void)
590 return !(mmd->new_vss_status_flags & VSS_NEXT)
591 && !(mmd->new_vss_status_flags & VSS_PLAYING);
595 * Check if the vss is currently stopped.
597 * \return Greater than zero if paused, zero otherwise.
600 unsigned int vss_stopped(void)
602 return (mmd->new_vss_status_flags & VSS_NEXT)
603 && !(mmd->new_vss_status_flags & VSS_PLAYING);
606 static int chk_barrier(const char *bname, const struct timeval *barrier,
607 struct timeval *diff, int print_log)
611 if (tv_diff(now, barrier, diff) > 0)
615 PARA_DEBUG_LOG("%s barrier: %lims left\n", bname, ms);
620 * != NULL: timeout for next chunk
621 * NULL: nothing to do
623 static struct timeval *vss_compute_timeout(struct vss_task *vsst)
625 static struct timeval the_timeout;
626 struct timeval next_chunk;
628 if (vss_next() && vsst->map) {
629 /* only sleep a bit, nec*/
630 the_timeout.tv_sec = 0;
631 the_timeout.tv_usec = 100;
634 if (chk_barrier("autoplay_delay", &vsst->autoplay_barrier,
635 &the_timeout, 1) < 0)
637 if (chk_barrier("eof", &vsst->eof_barrier, &the_timeout, 1) < 0)
639 if (chk_barrier("data send", &vsst->data_send_barrier,
640 &the_timeout, 1) < 0)
642 if (!vss_playing() || !vsst->map)
644 compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
645 &mmd->stream_start, &next_chunk);
646 if (chk_barrier("chunk", &next_chunk, &the_timeout, 0) >= 0) {
647 /* chunk is due or bof */
648 the_timeout.tv_sec = 0;
649 the_timeout.tv_usec = 0;
652 /* compute min of current timeout and next slice time */
653 compute_slice_timeout(&the_timeout);
657 static void vss_eof(struct vss_task *vsst)
662 if (mmd->new_vss_status_flags & VSS_NOMORE)
663 mmd->new_vss_status_flags = VSS_NEXT;
664 set_eof_barrier(vsst);
665 para_munmap(vsst->map, mmd->size);
667 mmd->chunks_sent = 0;
669 mmd->afd.afhi.seconds_total = 0;
670 mmd->afd.afhi.chunk_tv.tv_sec = 0;
671 mmd->afd.afhi.chunk_tv.tv_usec = 0;
672 free(mmd->afd.afhi.chunk_table);
673 mmd->afd.afhi.chunk_table = NULL;
679 static int need_to_request_new_audio_file(struct vss_task *vsst)
683 if (vsst->map) /* have audio file */
685 if (!vss_playing()) /* don't need one */
687 if (mmd->new_vss_status_flags & VSS_NOMORE)
689 if (vsst->afsss == AFS_SOCKET_AFD_PENDING) /* already requested one */
691 if (chk_barrier("autoplay_delay", &vsst->autoplay_barrier,
697 static void set_mmd_offset(void)
699 struct timeval offset;
700 tv_scale(mmd->current_chunk, &mmd->afd.afhi.chunk_tv, &offset);
701 mmd->offset = tv2ms(&offset);
705 * Compute the timeout for the main select-loop of the scheduler.
707 * \param s Pointer to the server scheduler.
708 * \param t Pointer to the vss task structure.
710 * Before the timeout is computed, the current vss status flags are evaluated
711 * and acted upon by calling appropriate functions from the lower layers.
712 * Possible actions include
714 * - request a new audio file from afs,
715 * - shutdown of all senders (stop/pause command),
716 * - reposition the stream (ff/jmp command).
718 static void vss_pre_select(struct sched *s, struct task *t)
722 struct vss_task *vsst = container_of(t, struct vss_task, task);
724 if (!vsst->map || vss_next() || vss_paused() || vss_repos()) {
725 struct fec_client *fc, *tmp;
726 for (i = 0; senders[i].name; i++)
727 if (senders[i].shutdown_clients)
728 senders[i].shutdown_clients();
729 list_for_each_entry_safe(fc, tmp, &fec_client_list, node)
730 fc->state = FEC_STATE_NONE;
731 mmd->stream_start.tv_sec = 0;
732 mmd->stream_start.tv_usec = 0;
736 else if (vss_paused()) {
737 if (mmd->chunks_sent)
738 set_eof_barrier(vsst);
739 mmd->chunks_sent = 0;
740 } else if (vss_repos()) {
741 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
742 set_eof_barrier(vsst);
743 mmd->chunks_sent = 0;
744 mmd->current_chunk = mmd->repos_request;
745 mmd->new_vss_status_flags &= ~VSS_REPOS;
748 if (need_to_request_new_audio_file(vsst)) {
749 PARA_DEBUG_LOG("ready and playing, but no audio file\n");
750 para_fd_set(vsst->afs_socket, &s->wfds, &s->max_fileno);
751 vsst->afsss = AFS_SOCKET_CHECK_FOR_WRITE;
753 para_fd_set(vsst->afs_socket, &s->rfds, &s->max_fileno);
754 for (i = 0; senders[i].name; i++) {
755 if (!senders[i].pre_select)
757 senders[i].pre_select(&s->max_fileno, &s->rfds, &s->wfds);
759 tv = vss_compute_timeout(vsst);
761 sched_request_timeout(tv, s);
764 static int recv_afs_msg(int afs_socket, int *fd, uint32_t *code, uint32_t *data)
766 char control[255], buf[8];
767 struct msghdr msg = {.msg_iov = NULL};
768 struct cmsghdr *cmsg;
774 iov.iov_len = sizeof(buf);
777 msg.msg_control = control;
778 msg.msg_controllen = sizeof(control);
779 memset(buf, 0, sizeof(buf));
780 ret = recvmsg(afs_socket, &msg, 0);
782 return -ERRNO_TO_PARA_ERROR(errno);
783 if (iov.iov_len != sizeof(buf))
784 return -E_AFS_SHORT_READ;
785 *code = *(uint32_t*)buf;
786 *data = *(uint32_t*)(buf + 4);
787 for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
788 if (cmsg->cmsg_level != SOL_SOCKET
789 || cmsg->cmsg_type != SCM_RIGHTS)
791 if ((cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int) != 1)
793 *fd = *(int *)CMSG_DATA(cmsg);
798 static void recv_afs_result(struct vss_task *vsst, fd_set *rfds)
800 int ret, passed_fd, shmid;
801 uint32_t afs_code = 0, afs_data = 0;
804 if (!FD_ISSET(vsst->afs_socket, rfds))
806 ret = recv_afs_msg(vsst->afs_socket, &passed_fd, &afs_code, &afs_data);
807 if (ret == -ERRNO_TO_PARA_ERROR(EAGAIN))
811 vsst->afsss = AFS_SOCKET_READY;
812 PARA_DEBUG_LOG("fd: %d, code: %u, shmid: %u\n", passed_fd, afs_code,
815 if (afs_code != NEXT_AUDIO_FILE)
820 ret = load_afd(shmid, &mmd->afd);
824 ret = fstat(passed_fd, &statbuf);
826 PARA_ERROR_LOG("fstat error:\n");
827 ret = -ERRNO_TO_PARA_ERROR(errno);
830 mmd->size = statbuf.st_size;
831 mmd->mtime = statbuf.st_mtime;
832 ret = para_mmap(mmd->size, PROT_READ, MAP_PRIVATE, passed_fd,
837 mmd->chunks_sent = 0;
838 mmd->current_chunk = 0;
842 mmd->new_vss_status_flags &= (~VSS_NEXT);
843 afh_get_header(&mmd->afd.afhi, vsst->map, &vsst->header_buf,
847 free(mmd->afd.afhi.chunk_table);
850 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
851 mmd->new_vss_status_flags = VSS_NEXT;
855 * Main sending function.
857 * This function gets called from vss_post_select(). It checks whether the next
858 * chunk of data should be pushed out. It obtains a pointer to the data to be
859 * sent out as well as its length from mmd->afd.afhi. This information is then
860 * passed to each supported sender's send() function as well as to the send()
861 * functions of each registered fec client.
863 static void vss_send(struct vss_task *vsst)
865 int i, fec_active = 0;
867 struct fec_client *fc, *tmp_fc;
869 if (!vsst->map || !vss_playing())
871 if (chk_barrier("eof", &vsst->eof_barrier, &due, 1) < 0)
873 if (chk_barrier("data send", &vsst->data_send_barrier,
876 list_for_each_entry_safe(fc, tmp_fc, &fec_client_list, node) {
877 if (fc->state == FEC_STATE_DISABLED)
879 if (!next_slice_is_due(fc, NULL)) {
883 if (compute_next_fec_slice(fc, vsst) <= 0)
885 PARA_DEBUG_LOG("sending %d:%d (%u bytes)\n", fc->group.num,
886 fc->current_slice_num, fc->mps);
887 fc->fcp->send_fec(fc->sc, (char *)fc->enc_buf, fc->mps);
888 fc->current_slice_num++;
891 if (mmd->current_chunk >= mmd->afd.afhi.chunks_total) { /* eof */
893 mmd->new_vss_status_flags |= VSS_NEXT;
896 compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
897 &mmd->stream_start, &due);
898 if (tv_diff(&due, now, NULL) <= 0) {
902 if (!mmd->chunks_sent) {
903 mmd->stream_start = *now;
908 * We call the send function also in case of empty chunks as
909 * they might have still some data queued which can be sent in
912 afh_get_chunk(mmd->current_chunk, &mmd->afd.afhi, vsst->map,
914 for (i = 0; senders[i].name; i++) {
915 if (!senders[i].send)
917 senders[i].send(mmd->current_chunk, mmd->chunks_sent,
918 buf, len, vsst->header_buf, vsst->header_len);
921 mmd->current_chunk++;
925 static void vss_post_select(struct sched *s, struct task *t)
928 struct vss_task *vsst = container_of(t, struct vss_task, task);
931 if (mmd->sender_cmd_data.cmd_num >= 0) {
932 int num = mmd->sender_cmd_data.cmd_num,
933 sender_num = mmd->sender_cmd_data.sender_num;
935 if (senders[sender_num].client_cmds[num]) {
936 ret = senders[sender_num].client_cmds[num]
937 (&mmd->sender_cmd_data);
939 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
941 mmd->sender_cmd_data.cmd_num = -1;
943 if (vsst->afsss != AFS_SOCKET_CHECK_FOR_WRITE)
944 recv_afs_result(vsst, &s->rfds);
945 else if (FD_ISSET(vsst->afs_socket, &s->wfds)) {
946 PARA_NOTICE_LOG("requesting new fd from afs\n");
947 ret = send_buffer(vsst->afs_socket, "new");
949 PARA_CRIT_LOG("%s\n", para_strerror(-ret));
951 vsst->afsss = AFS_SOCKET_AFD_PENDING;
953 for (i = 0; senders[i].name; i++) {
954 if (!senders[i].post_select)
956 senders[i].post_select(&s->rfds, &s->wfds);
958 if ((vss_playing() && !(mmd->vss_status_flags & VSS_PLAYING)) ||
959 (vss_next() && vss_playing()))
960 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
965 * Initialize the virtual streaming system task.
967 * \param afs_socket The fd for communication with afs.
969 * This also initializes all supported senders and starts streaming
970 * if the --autoplay command line flag was given.
972 void init_vss_task(int afs_socket)
974 static struct vss_task vss_task_struct, *vsst = &vss_task_struct;
976 char *hn = para_hostname(), *home = para_homedir();
977 long unsigned announce_time = conf.announce_time_arg > 0?
978 conf.announce_time_arg : 300,
979 autoplay_delay = conf.autoplay_delay_arg > 0?
980 conf.autoplay_delay_arg : 0;
981 vsst->header_interval.tv_sec = 5; /* should this be configurable? */
982 vsst->afs_socket = afs_socket;
983 vsst->task.pre_select = vss_pre_select;
984 vsst->task.post_select = vss_post_select;
985 ms2tv(announce_time, &vsst->announce_tv);
986 PARA_INFO_LOG("announce timeval: %lums\n", tv2ms(&vsst->announce_tv));
987 INIT_LIST_HEAD(&fec_client_list);
988 for (i = 0; senders[i].name; i++) {
989 PARA_NOTICE_LOG("initializing %s sender\n", senders[i].name);
990 senders[i].init(&senders[i]);
994 mmd->sender_cmd_data.cmd_num = -1;
995 if (conf.autoplay_given) {
997 mmd->vss_status_flags |= VSS_PLAYING;
998 mmd->new_vss_status_flags |= VSS_PLAYING;
999 ms2tv(autoplay_delay, &tmp);
1000 tv_add(now, &tmp, &vsst->autoplay_barrier);
1001 tv_add(&vsst->autoplay_barrier, &vsst->announce_tv,
1002 &vsst->data_send_barrier);
1004 register_task(&vsst->task);