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
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;
135 * Describes one connected FEC client.
138 /** If negative, this client is temporarily disabled. */
140 /** Parameters requested by the client. */
141 struct fec_client_parms *fcp;
142 /** Used by the core FEC code. */
143 struct fec_parms *parms;
144 /** The position of this client in the fec client list. */
145 struct list_head node;
146 /** When the first slice for this client was sent. */
147 struct timeval stream_start;
148 /** The first chunk sent to this FEC client. */
149 int first_stream_chunk;
150 /** Describes the current group. */
151 struct fec_group group;
152 /** The current slice. */
153 uint8_t current_slice_num;
154 /** The data to be FEC-encoded (point to a region within the mapped audio file). */
155 const unsigned char **src_data;
156 /** Last time an audio header was sent. */
157 struct timeval next_header_time;
158 /** Used for the last source pointer of an audio file. */
159 unsigned char *extra_src_buf;
160 /** Extra slices needed to store largest chunk + header. */
161 int num_extra_slices;
162 /** Contains the FEC-encoded data. */
163 unsigned char *enc_buf;
167 * Get the chunk time of the current audio file.
169 * \return A pointer to a struct containing the chunk time, or NULL,
170 * if currently no audio file is selected.
172 struct timeval *vss_chunk_time(void)
174 if (mmd->afd.afhi.chunk_tv.tv_sec == 0 &&
175 mmd->afd.afhi.chunk_tv.tv_usec == 0)
177 return &mmd->afd.afhi.chunk_tv;
181 * Write a fec header to a buffer.
183 * \param buf The buffer to write to.
184 * \param h The fec header to write.
186 static void write_fec_header(struct fec_client *fc, struct vss_task *vsst)
188 char *buf = (char *)fc->enc_buf;
189 struct fec_group *g = &fc->group;
190 struct fec_client_parms *p = fc->fcp;
192 write_u32(buf, FEC_MAGIC);
194 write_u8(buf + 4, p->slices_per_group + fc->num_extra_slices);
195 write_u8(buf + 5, p->data_slices_per_group + fc->num_extra_slices);
196 write_u32(buf + 6, g->num_header_slices? vsst->header_len : 0);
198 write_u32(buf + 10, g->num);
199 write_u32(buf + 14, g->bytes);
201 write_u8(buf + 18, fc->current_slice_num);
202 write_u16(buf + 20, p->max_slice_bytes - FEC_HEADER_SIZE);
203 write_u8(buf + 22, g->first_chunk? 0 : 1);
204 write_u8(buf + 23, vsst->header_len? 1 : 0);
205 memset(buf + 24, 0, 7);
208 static int need_audio_header(struct fec_client *fc, struct vss_task *vsst)
210 if (!mmd->current_chunk) {
211 tv_add(now, &vsst->header_interval, &fc->next_header_time);
214 if (!vsst->header_buf)
216 if (!vsst->header_len)
218 if (fc->group.num && tv_diff(&fc->next_header_time, now, NULL) > 0)
220 tv_add(now, &vsst->header_interval, &fc->next_header_time);
224 static int num_slices(long unsigned bytes, struct fec_client *fc, uint8_t *result)
226 unsigned long m = fc->fcp->max_slice_bytes - FEC_HEADER_SIZE;
227 unsigned rv, redundant_slices = fc->fcp->slices_per_group
228 - fc->fcp->data_slices_per_group;
232 rv = (bytes + m - 1) / m;
233 if (rv + redundant_slices > 255)
239 /* set group start and group duration */
240 static void set_group_timing(struct fec_client *fc, struct fec_group *g)
242 struct timeval *chunk_tv = vss_chunk_time();
244 tv_scale(g->num_chunks, chunk_tv, &g->duration);
245 tv_divide(fc->fcp->slices_per_group + fc->num_extra_slices,
246 &g->duration, &g->slice_duration);
247 PARA_DEBUG_LOG("durations (group/chunk/slice): %lu/%lu/%lu\n",
248 tv2ms(&g->duration), tv2ms(chunk_tv), tv2ms(&g->slice_duration));
251 static int setup_next_fec_group(struct fec_client *fc, struct vss_task *vsst)
253 int ret, i, k, data_slices;
255 const char *buf, *start_buf;
256 struct fec_group *g = &fc->group;
257 unsigned slice_bytes = fc->fcp->max_slice_bytes - FEC_HEADER_SIZE;
258 uint32_t max_data_size;
260 if (fc->first_stream_chunk < 0) {
261 uint8_t hs, ds; /* needed header/data slices */
262 uint8_t rs = fc->fcp->slices_per_group
263 - fc->fcp->data_slices_per_group; /* redundant slices */
266 ret = num_slices(vsst->header_len, fc, &hs);
269 ret = num_slices(afh_get_largest_chunk_size(&mmd->afd.afhi),
276 if (k < fc->fcp->data_slices_per_group)
277 k = fc->fcp->data_slices_per_group;
279 fc->num_extra_slices = k - fc->fcp->data_slices_per_group;
280 PARA_NOTICE_LOG("fec parms %d:%d:%d (%d extra slices)\n",
281 slice_bytes, k, n, fc->num_extra_slices);
283 fc->src_data = para_realloc(fc->src_data, k * sizeof(char *));
284 ret = fec_new(k, n, &fc->parms);
287 fc->stream_start = *now;
288 fc->first_stream_chunk = mmd->current_chunk;
289 g->first_chunk = mmd->current_chunk;
294 * Start and duration of this group depend only on the previous
295 * group. Compute the new group start as g->start += g->duration.
297 struct timeval tmp = g->start;
298 tv_add(&tmp, &g->duration, &g->start);
299 k = fc->fcp->data_slices_per_group + fc->num_extra_slices;
300 set_group_timing(fc, g);
301 g->first_chunk += g->num_chunks;
304 if (g->first_chunk >= mmd->afd.afhi.chunks_total)
306 if (need_audio_header(fc, vsst)) {
307 ret = num_slices(vsst->header_len, fc, &g->num_header_slices);
311 g->num_header_slices = 0;
312 afh_get_chunk(g->first_chunk, &mmd->afd.afhi, vsst->map, &start_buf,
314 data_slices = k - g->num_header_slices;
316 max_data_size = slice_bytes * data_slices;
318 for (i = g->first_chunk; i < mmd->afd.afhi.chunks_total; i++) {
319 afh_get_chunk(i, &mmd->afd.afhi, vsst->map, &buf, &len);
320 if (g->bytes + len > max_data_size)
324 g->num_chunks = i - g->first_chunk;
325 assert(g->num_chunks);
326 fc->current_slice_num = 0;
328 set_group_timing(fc, g);
330 /* setup header slices */
331 buf = vsst->header_buf;
332 for (i = 0; i < g->num_header_slices; i++) {
333 fc->src_data[i] = (const unsigned char *)buf;
337 /* setup data slices */
339 for (i = g->num_header_slices; i < k; i++) {
340 if (buf + slice_bytes > vsst->map + mmd->size)
342 * Can not use the memory mapped audio file for this
343 * slice as it goes beyond the map. This slice will not
347 fc->src_data[i] = (const unsigned char *)buf;
351 uint32_t payload_size = vsst->map + mmd->size - buf;
352 memcpy(fc->extra_src_buf, buf, payload_size);
353 fc->src_data[i] = fc->extra_src_buf;
355 /* use arbitrary data for all remaining slices */
358 fc->src_data[i] = (const unsigned char *)buf;
360 PARA_DEBUG_LOG("FEC group %d: %d chunks (%d - %d), "
361 "%d header slices, %d data slices\n",
362 g->num, g->num_chunks, g->first_chunk,
363 g->first_chunk + g->num_chunks - 1,
364 g->num_header_slices, data_slices
369 static int compute_next_fec_slice(struct fec_client *fc, struct vss_task *vsst)
371 assert(fc->error >= 0);
372 if (fc->first_stream_chunk < 0 || fc->current_slice_num
373 == fc->fcp->slices_per_group + fc->num_extra_slices) {
374 int ret = setup_next_fec_group(fc, vsst);
378 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
379 PARA_ERROR_LOG("FEC client temporarily disabled\n");
384 write_fec_header(fc, vsst);
385 fec_encode(fc->parms, fc->src_data, fc->enc_buf + FEC_HEADER_SIZE,
386 fc->current_slice_num,
387 fc->fcp->max_slice_bytes - FEC_HEADER_SIZE);
392 * Return a buffer that marks the end of the stream.
394 * \param buf Result pointer.
395 * \return The length of the eof buffer.
397 * This is used for (multicast) udp streaming where closing the socket on the
398 * sender might not give rise to an eof condition at the peer.
400 size_t vss_get_fec_eof_packet(const char **buf)
402 static const char fec_eof_packet[FEC_HEADER_SIZE] = FEC_EOF_PACKET;
403 *buf = fec_eof_packet;
404 return FEC_HEADER_SIZE;
408 * Add one entry to the list of active fec clients.
410 * \param fcp Describes the fec parameters to be used for this client.
411 * \param result An opaque pointer that must be used by remove the client later.
415 int vss_add_fec_client(struct fec_client_parms *fcp, struct fec_client **result)
418 struct fec_client *fc;
420 if (fcp->max_slice_bytes < FEC_HEADER_SIZE + fcp->data_slices_per_group)
421 return -ERRNO_TO_PARA_ERROR(EINVAL);
422 fc = para_calloc(sizeof(*fc));
424 ret = fec_new(fcp->data_slices_per_group, fcp->slices_per_group,
428 fc->first_stream_chunk = -1; /* stream not yet started */
429 fc->src_data = para_malloc(fc->fcp->slices_per_group * sizeof(char *));
430 fc->enc_buf = para_calloc(fc->fcp->max_slice_bytes);
431 fc->num_extra_slices = 0;
432 fc->extra_src_buf = para_calloc(fc->fcp->max_slice_bytes);
433 fc->next_header_time.tv_sec = 0;
434 para_list_add(&fc->node, &fec_client_list);
445 * Remove one entry from the list of active fec clients.
447 * \param fc The client to be removed.
449 void vss_del_fec_client(struct fec_client *fc)
454 free(fc->extra_src_buf);
460 * Compute if/when next slice is due. If it isn't due yet and \a diff is
461 * not \p Null, compute the time difference next - now, where
463 * next = stream_start + (first_group_chunk - first_stream_chunk)
464 * * chunk_time + slice_num * slice_time
466 static int next_slice_is_due(struct fec_client *fc, struct timeval *diff)
468 struct timeval tmp, next;
471 if (fc->first_stream_chunk < 0)
473 tv_scale(fc->current_slice_num, &fc->group.slice_duration, &tmp);
474 tv_add(&tmp, &fc->group.start, &next);
475 ret = tv_diff(&next, now, diff);
476 return ret < 0? 1 : 0;
479 static void compute_slice_timeout(struct timeval *timeout)
481 struct fec_client *fc;
483 assert(vss_playing());
484 list_for_each_entry(fc, &fec_client_list, node) {
489 if (next_slice_is_due(fc, &diff)) {
491 timeout->tv_usec = 0;
494 /* timeout = min(timeout, diff) */
495 if (tv_diff(&diff, timeout, NULL) < 0)
500 static void set_eof_barrier(struct vss_task *vsst)
502 struct fec_client *fc;
503 struct timeval timeout = {1, 0}, *chunk_tv = vss_chunk_time();
507 list_for_each_entry(fc, &fec_client_list, node) {
508 struct timeval group_duration;
512 tv_scale(fc->group.num_chunks, chunk_tv, &group_duration);
513 if (tv_diff(&timeout, &group_duration, NULL) < 0)
514 timeout = group_duration;
517 tv_add(now, &timeout, &vsst->eof_barrier);
521 * Check if vss status flag \a P (playing) is set.
523 * \return Greater than zero if playing, zero otherwise.
526 unsigned int vss_playing(void)
528 return mmd->new_vss_status_flags & VSS_PLAYING;
532 * Check if the \a N (next) status flag is set.
534 * \return Greater than zero if set, zero if not.
537 unsigned int vss_next(void)
539 return mmd->new_vss_status_flags & VSS_NEXT;
543 * Check if a reposition request is pending.
545 * \return Greater than zero if true, zero otherwise.
548 unsigned int vss_repos(void)
550 return mmd->new_vss_status_flags & VSS_REPOS;
554 * Check if the vss is currently paused.
556 * \return Greater than zero if paused, zero otherwise.
559 unsigned int vss_paused(void)
561 return !(mmd->new_vss_status_flags & VSS_NEXT)
562 && !(mmd->new_vss_status_flags & VSS_PLAYING);
566 * Check if the vss is currently stopped.
568 * \return Greater than zero if paused, zero otherwise.
571 unsigned int vss_stopped(void)
573 return (mmd->new_vss_status_flags & VSS_NEXT)
574 && !(mmd->new_vss_status_flags & VSS_PLAYING);
577 static int chk_barrier(const char *bname, const struct timeval *barrier,
578 struct timeval *diff, int print_log)
582 if (tv_diff(now, barrier, diff) > 0)
586 PARA_DEBUG_LOG("%s barrier: %lims left\n", bname, ms);
591 * != NULL: timeout for next chunk
592 * NULL: nothing to do
594 static struct timeval *vss_compute_timeout(struct vss_task *vsst)
596 static struct timeval the_timeout;
597 struct timeval next_chunk;
599 if (vss_next() && vsst->map) {
600 /* only sleep a bit, nec*/
601 the_timeout.tv_sec = 0;
602 the_timeout.tv_usec = 100;
605 if (chk_barrier("autoplay_delay", &vsst->autoplay_barrier,
606 &the_timeout, 1) < 0)
608 if (chk_barrier("eof", &vsst->eof_barrier, &the_timeout, 1) < 0)
610 if (chk_barrier("data send", &vsst->data_send_barrier,
611 &the_timeout, 1) < 0)
613 if (!vss_playing() || !vsst->map)
615 compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
616 &mmd->stream_start, &next_chunk);
617 if (chk_barrier("chunk", &next_chunk, &the_timeout, 0) >= 0) {
618 /* chunk is due or bof */
619 the_timeout.tv_sec = 0;
620 the_timeout.tv_usec = 0;
623 /* compute min of current timeout and next slice time */
624 compute_slice_timeout(&the_timeout);
628 static void vss_eof(struct vss_task *vsst)
633 if (mmd->new_vss_status_flags & VSS_NOMORE)
634 mmd->new_vss_status_flags = VSS_NEXT;
635 set_eof_barrier(vsst);
636 para_munmap(vsst->map, mmd->size);
638 mmd->chunks_sent = 0;
640 mmd->afd.afhi.seconds_total = 0;
641 mmd->afd.afhi.chunk_tv.tv_sec = 0;
642 mmd->afd.afhi.chunk_tv.tv_usec = 0;
643 free(mmd->afd.afhi.chunk_table);
644 mmd->afd.afhi.chunk_table = NULL;
651 * Get the list of all supported audio formats.
653 * \return Aa space separated list of all supported audio formats
654 * It is not allocated at runtime, i.e. there is no need to free
655 * the returned string in the caller.
657 const char *supported_audio_formats(void)
659 return SUPPORTED_AUDIO_FORMATS;
662 static int need_to_request_new_audio_file(struct vss_task *vsst)
666 if (vsst->map) /* have audio file */
668 if (!vss_playing()) /* don't need one */
670 if (mmd->new_vss_status_flags & VSS_NOMORE)
672 if (vsst->afsss == AFS_SOCKET_AFD_PENDING) /* already requested one */
674 if (chk_barrier("autoplay_delay", &vsst->autoplay_barrier,
680 static void set_mmd_offset(void)
682 struct timeval offset;
683 tv_scale(mmd->current_chunk, &mmd->afd.afhi.chunk_tv, &offset);
684 mmd->offset = tv2ms(&offset);
688 * Compute the timeout for the main select-loop of the scheduler.
690 * \param s Pointer to the server scheduler.
691 * \param t Pointer to the vss task structure.
693 * Before the timeout is computed, the current vss status flags are evaluated
694 * and acted upon by calling appropriate functions from the lower layers.
695 * Possible actions include
697 * - request a new audio file from afs,
698 * - shutdown of all senders (stop/pause command),
699 * - reposition the stream (ff/jmp command).
701 static void vss_pre_select(struct sched *s, struct task *t)
704 struct timeval *tv, diff;
705 struct vss_task *vsst = container_of(t, struct vss_task, task);
707 if (!vsst->map || vss_next() || vss_paused() || vss_repos()) {
708 struct fec_client *fc, *tmp;
709 for (i = 0; senders[i].name; i++)
710 if (senders[i].shutdown_clients)
711 senders[i].shutdown_clients();
712 list_for_each_entry_safe(fc, tmp, &fec_client_list, node) {
713 fc->first_stream_chunk = -1;
716 mmd->stream_start.tv_sec = 0;
717 mmd->stream_start.tv_usec = 0;
721 else if (vss_paused()) {
722 if (mmd->chunks_sent)
723 set_eof_barrier(vsst);
724 mmd->chunks_sent = 0;
725 } else if (vss_repos()) {
726 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
727 set_eof_barrier(vsst);
728 mmd->chunks_sent = 0;
729 mmd->current_chunk = mmd->repos_request;
730 mmd->new_vss_status_flags &= ~VSS_REPOS;
733 if (need_to_request_new_audio_file(vsst)) {
734 PARA_DEBUG_LOG("ready and playing, but no audio file\n");
735 para_fd_set(vsst->afs_socket, &s->wfds, &s->max_fileno);
736 vsst->afsss = AFS_SOCKET_CHECK_FOR_WRITE;
738 para_fd_set(vsst->afs_socket, &s->rfds, &s->max_fileno);
739 for (i = 0; senders[i].name; i++) {
740 if (!senders[i].pre_select)
742 senders[i].pre_select(&s->max_fileno, &s->rfds, &s->wfds);
744 tv = vss_compute_timeout(vsst);
745 if (tv && tv_diff(tv, &s->timeout, &diff) < 0)
749 static int recv_afs_msg(int afs_socket, int *fd, uint32_t *code, uint32_t *data)
751 char control[255], buf[8];
752 struct msghdr msg = {.msg_iov = NULL};
753 struct cmsghdr *cmsg;
759 iov.iov_len = sizeof(buf);
762 msg.msg_control = control;
763 msg.msg_controllen = sizeof(control);
764 memset(buf, 0, sizeof(buf));
765 ret = recvmsg(afs_socket, &msg, 0);
767 return -ERRNO_TO_PARA_ERROR(errno);
768 if (iov.iov_len != sizeof(buf))
769 return -E_AFS_SHORT_READ;
770 *code = *(uint32_t*)buf;
771 *data = *(uint32_t*)(buf + 4);
772 for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
773 if (cmsg->cmsg_level != SOL_SOCKET
774 || cmsg->cmsg_type != SCM_RIGHTS)
776 if ((cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int) != 1)
778 *fd = *(int *)CMSG_DATA(cmsg);
783 static void recv_afs_result(struct vss_task *vsst)
785 int ret, passed_fd, shmid;
786 uint32_t afs_code = 0, afs_data = 0;
789 vsst->afsss = AFS_SOCKET_READY;
790 ret = recv_afs_msg(vsst->afs_socket, &passed_fd, &afs_code, &afs_data);
793 PARA_DEBUG_LOG("fd: %d, code: %u, shmid: %u\n", passed_fd, afs_code,
796 if (afs_code != NEXT_AUDIO_FILE)
801 ret = load_afd(shmid, &mmd->afd);
805 ret = fstat(passed_fd, &statbuf);
807 PARA_ERROR_LOG("fstat error:\n");
808 ret = -ERRNO_TO_PARA_ERROR(errno);
811 mmd->size = statbuf.st_size;
812 mmd->mtime = statbuf.st_mtime;
813 ret = para_mmap(mmd->size, PROT_READ, MAP_PRIVATE, passed_fd,
818 mmd->chunks_sent = 0;
819 mmd->current_chunk = 0;
823 mmd->new_vss_status_flags &= (~VSS_NEXT);
824 afh_get_header(&mmd->afd.afhi, vsst->map, &vsst->header_buf,
828 free(mmd->afd.afhi.chunk_table);
831 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
832 mmd->new_vss_status_flags = VSS_NEXT;
836 * Main sending function.
838 * This function gets called from vss_post_select(). It checks whether the next
839 * chunk of data should be pushed out. It obtains a pointer to the data to be
840 * sent out as well as its length from mmd->afd.afhi. This information is then
841 * passed to each supported sender's send() function as well as to the send()
842 * functions of each registered fec client.
844 static void vss_send(struct vss_task *vsst)
846 int i, fec_active = 0;
848 struct fec_client *fc, *tmp_fc;
850 if (!vsst->map || !vss_playing())
852 if (chk_barrier("eof", &vsst->eof_barrier, &due, 1) < 0)
854 if (chk_barrier("data send", &vsst->data_send_barrier,
857 list_for_each_entry_safe(fc, tmp_fc, &fec_client_list, node) {
860 if (!next_slice_is_due(fc, NULL)) {
864 if (compute_next_fec_slice(fc, vsst) <= 0)
866 PARA_DEBUG_LOG("sending %d:%d (%u bytes)\n", fc->group.num,
867 fc->current_slice_num, fc->fcp->max_slice_bytes);
868 fc->fcp->send((char *)fc->enc_buf,
869 fc->fcp->max_slice_bytes,
870 fc->fcp->private_data);
871 fc->current_slice_num++;
874 if (mmd->current_chunk >= mmd->afd.afhi.chunks_total) { /* eof */
876 mmd->new_vss_status_flags |= VSS_NEXT;
879 compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
880 &mmd->stream_start, &due);
881 if (tv_diff(&due, now, NULL) <= 0) {
885 if (!mmd->chunks_sent) {
886 mmd->stream_start = *now;
891 * We call the send function also in case of empty chunks as
892 * they might have still some data queued which can be sent in
895 afh_get_chunk(mmd->current_chunk, &mmd->afd.afhi, vsst->map,
897 for (i = 0; senders[i].name; i++) {
898 if (!senders[i].send)
900 senders[i].send(mmd->current_chunk, mmd->chunks_sent,
901 buf, len, vsst->header_buf, vsst->header_len);
904 mmd->current_chunk++;
908 static void vss_post_select(struct sched *s, struct task *t)
911 struct vss_task *vsst = container_of(t, struct vss_task, task);
914 if (mmd->sender_cmd_data.cmd_num >= 0) {
915 int num = mmd->sender_cmd_data.cmd_num,
916 sender_num = mmd->sender_cmd_data.sender_num;
918 if (senders[sender_num].client_cmds[num])
919 senders[sender_num].client_cmds[num](&mmd->sender_cmd_data);
920 mmd->sender_cmd_data.cmd_num = -1;
922 if (vsst->afsss != AFS_SOCKET_CHECK_FOR_WRITE) {
923 if (FD_ISSET(vsst->afs_socket, &s->rfds))
924 recv_afs_result(vsst);
925 } else if (FD_ISSET(vsst->afs_socket, &s->wfds)) {
926 PARA_NOTICE_LOG("requesting new fd from afs\n");
927 ret = send_buffer(vsst->afs_socket, "new");
929 PARA_CRIT_LOG("%s\n", para_strerror(-ret));
931 vsst->afsss = AFS_SOCKET_AFD_PENDING;
933 for (i = 0; senders[i].name; i++) {
934 if (!senders[i].post_select)
936 senders[i].post_select(&s->rfds, &s->wfds);
938 if ((vss_playing() && !(mmd->vss_status_flags & VSS_PLAYING)) ||
939 (vss_next() && vss_playing()))
940 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
945 * Initialize the virtual streaming system task.
947 * \param afs_socket The fd for communication with afs.
949 * This also initializes all supported senders and starts streaming
950 * if the --autoplay command line flag was given.
952 void init_vss_task(int afs_socket)
954 static struct vss_task vss_task_struct, *vsst = &vss_task_struct;
956 char *hn = para_hostname(), *home = para_homedir();
957 long unsigned announce_time = conf.announce_time_arg > 0?
958 conf.announce_time_arg : 300,
959 autoplay_delay = conf.autoplay_delay_arg > 0?
960 conf.autoplay_delay_arg : 0;
961 vsst->header_interval.tv_sec = 5; /* should this be configurable? */
962 vsst->afs_socket = afs_socket;
963 vsst->task.pre_select = vss_pre_select;
964 vsst->task.post_select = vss_post_select;
965 ms2tv(announce_time, &vsst->announce_tv);
966 PARA_INFO_LOG("announce timeval: %lums\n", tv2ms(&vsst->announce_tv));
967 INIT_LIST_HEAD(&fec_client_list);
968 for (i = 0; senders[i].name; i++) {
969 PARA_NOTICE_LOG("initializing %s sender\n", senders[i].name);
970 senders[i].init(&senders[i]);
974 mmd->sender_cmd_data.cmd_num = -1;
975 if (conf.autoplay_given) {
977 mmd->vss_status_flags |= VSS_PLAYING;
978 mmd->new_vss_status_flags |= VSS_PLAYING;
979 ms2tv(autoplay_delay, &tmp);
980 tv_add(now, &tmp, &vsst->autoplay_barrier);
981 tv_add(&vsst->autoplay_barrier, &vsst->announce_tv,
982 &vsst->data_send_barrier);
984 register_task(&vsst->task);