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
19 #include "portable_io.h"
26 #include "server.cmdline.h"
34 extern struct misc_meta_data *mmd;
36 extern void dccp_send_init(struct sender *);
37 extern void http_send_init(struct sender *);
38 extern void udp_send_init(struct sender *);
40 /** The list of supported senders. */
41 struct sender senders[] = {
44 .init = http_send_init,
48 .init = dccp_send_init,
52 .init = udp_send_init,
59 /** The possible states of the afs socket. */
60 enum afs_socket_status {
61 /** Socket is inactive. */
63 /** Socket fd was included in the write fd set for select(). */
64 AFS_SOCKET_CHECK_FOR_WRITE,
65 /** vss wrote a request to the socket and waits for reply from afs. */
66 AFS_SOCKET_AFD_PENDING
69 /** The task structure for the virtual streaming system. */
71 /** Copied from the -announce_time command line option. */
72 struct timeval announce_tv;
73 /** End of the announcing interval. */
74 struct timeval data_send_barrier;
75 /** End of the EOF interval. */
76 struct timeval eof_barrier;
77 /** Only used if --autoplay_delay was given. */
78 struct timeval autoplay_barrier;
79 /** Used for afs-server communication. */
81 /** The current state of \a afs_socket. */
82 enum afs_socket_status afsss;
83 /** The memory mapped audio file. */
85 /** Used by the scheduler. */
87 /** Pointer to the header of the mapped audio file. */
88 const char *header_buf;
89 /** Length of the audio file header. */
91 /** Time between audio file headers are sent. */
92 struct timeval header_interval;
96 * The list of currently connected fec clients.
98 * Senders may use \ref vss_add_fec_client() to add entries to the list.
100 static struct list_head fec_client_list;
103 * Data associated with one FEC group.
105 * A FEC group consists of a fixed number of slices and this number is given by
106 * the \a slices_per_group parameter of struct \ref fec_client_parms. Each FEC
107 * group contains a number of chunks of the current audio file.
109 * FEC slices directly correspond to the data packages sent by the paraslash
110 * senders that use FEC. Each slice is identified by its group number and its
111 * number within the group. All slices have the same size, but the last slice
112 * of the group may not be filled entirely.
115 /** The number of the FEC group. */
117 /** Number of bytes in this group. */
119 /** The first chunk of the current audio file belonging to the group. */
120 uint32_t first_chunk;
121 /** The number of chunks contained in this group. */
123 /** When the first chunk was sent. */
124 struct timeval start;
125 /** The group duration divided by the number of slices. */
126 struct timeval slice_duration;
127 /** Group contains the audio file header that occupies that many slices. */
128 uint8_t num_header_slices;
132 * Describes one connected FEC client.
135 /** If negative, this client is temporarily disabled. */
137 /** Parameters requested by the client. */
138 struct fec_client_parms *fcp;
139 /** Used by the core FEC code. */
140 struct fec_parms *parms;
141 /** The position of this client in the fec client list. */
142 struct list_head node;
143 /** When the first slice for this client was sent. */
144 struct timeval stream_start;
145 /** The first chunk sent to this FEC client. */
146 int first_stream_chunk;
147 /** Describes the current group. */
148 struct fec_group group;
149 /** The current slice. */
150 uint8_t current_slice_num;
151 /** The data to be FEC-encoded (point to a region within the mapped audio file). */
152 const unsigned char **src_data;
153 /** Last time an audio header was sent. */
154 struct timeval next_header_time;
155 /** Used for the last source pointer of an audio file. */
156 unsigned char *extra_src_buf;
157 /** Extra slices needed to store largest chunk + header. */
158 int num_extra_slices;
159 /** Contains the FEC-encoded data. */
160 unsigned char *enc_buf;
164 * Get the chunk time of the current audio file.
166 * \return A pointer to a struct containing the chunk time, or NULL,
167 * if currently no audio file is selected.
169 struct timeval *vss_chunk_time(void)
171 if (mmd->afd.afhi.chunk_tv.tv_sec == 0 &&
172 mmd->afd.afhi.chunk_tv.tv_usec == 0)
174 return &mmd->afd.afhi.chunk_tv;
178 * Write a fec header to a buffer.
180 * \param buf The buffer to write to.
181 * \param h The fec header to write.
183 static void write_fec_header(struct fec_client *fc, struct vss_task *vsst)
185 char *buf = (char *)fc->enc_buf;
186 struct fec_group *g = &fc->group;
187 struct fec_client_parms *p = fc->fcp;
189 write_u32(buf, FEC_MAGIC);
191 write_u8(buf + 4, p->slices_per_group + fc->num_extra_slices);
192 write_u8(buf + 5, p->data_slices_per_group + fc->num_extra_slices);
193 write_u32(buf + 6, g->num_header_slices? vsst->header_len : 0);
195 write_u32(buf + 10, g->num);
196 write_u32(buf + 14, g->bytes);
198 write_u8(buf + 18, fc->current_slice_num);
199 write_u16(buf + 20, p->max_slice_bytes - FEC_HEADER_SIZE);
200 write_u8(buf + 22, g->first_chunk? 0 : 1);
201 write_u8(buf + 23, vsst->header_len? 1 : 0);
202 memset(buf + 24, 0, 7);
205 static int need_audio_header(struct fec_client *fc, struct vss_task *vsst)
207 if (!mmd->current_chunk) {
208 tv_add(now, &vsst->header_interval, &fc->next_header_time);
211 if (!vsst->header_buf)
213 if (!vsst->header_len)
215 if (fc->group.num && tv_diff(&fc->next_header_time, now, NULL) > 0)
217 tv_add(now, &vsst->header_interval, &fc->next_header_time);
221 static int num_slices(long unsigned bytes, struct fec_client *fc, uint8_t *result)
223 unsigned long m = fc->fcp->max_slice_bytes - FEC_HEADER_SIZE;
224 unsigned rv, redundant_slices = fc->fcp->slices_per_group
225 - fc->fcp->data_slices_per_group;
229 rv = (bytes + m - 1) / m;
230 if (rv + redundant_slices > 255)
236 static int setup_next_fec_group(struct fec_client *fc, struct vss_task *vsst)
238 int ret, i, k, data_slices;
240 const char *buf, *start_buf;
241 struct timeval tmp, *chunk_tv = vss_chunk_time();
242 struct fec_group *g = &fc->group;
243 unsigned slice_bytes = fc->fcp->max_slice_bytes - FEC_HEADER_SIZE;
244 uint32_t max_data_size;
247 k = fc->fcp->data_slices_per_group + fc->num_extra_slices;
248 if (fc->first_stream_chunk < 0) {
249 uint32_t largest = afh_get_largest_chunk_size(&mmd->afd.afhi)
251 uint8_t needed, want;
253 ret = num_slices(largest, fc, &needed);
256 if (needed > fc->fcp->data_slices_per_group)
257 PARA_WARNING_LOG("fec parms insufficient for this audio file\n");
258 want = PARA_MAX(needed, fc->fcp->data_slices_per_group);
261 fc->src_data = para_realloc(fc->src_data, want * sizeof(char *));
262 ret = fec_new(want, want + fc->fcp->slices_per_group
263 - fc->fcp->data_slices_per_group, &fc->parms);
267 fc->num_extra_slices = 0;
268 if (k > fc->fcp->data_slices_per_group) {
269 fc->num_extra_slices = k - fc->fcp->data_slices_per_group;
270 PARA_NOTICE_LOG("using %d extra slices\n",
271 fc->num_extra_slices);
274 fc->stream_start = *now;
275 fc->first_stream_chunk = mmd->current_chunk;
276 g->first_chunk = mmd->current_chunk;
279 g->first_chunk += g->num_chunks;
282 if (g->first_chunk >= mmd->afd.afhi.chunks_total)
284 if (need_audio_header(fc, vsst)) {
285 ret = num_slices(vsst->header_len, fc, &g->num_header_slices);
289 g->num_header_slices = 0;
290 afh_get_chunk(g->first_chunk, &mmd->afd.afhi, vsst->map, &start_buf,
292 data_slices = k - g->num_header_slices;
294 max_data_size = slice_bytes * data_slices;
296 for (i = g->first_chunk; i < mmd->afd.afhi.chunks_total; i++) {
297 afh_get_chunk(i, &mmd->afd.afhi, vsst->map, &buf, &len);
298 if (g->bytes + len > max_data_size)
302 g->num_chunks = i - g->first_chunk;
303 assert(g->num_chunks);
304 fc->current_slice_num = 0;
306 /* setup header slices */
307 buf = vsst->header_buf;
308 for (i = 0; i < g->num_header_slices; i++) {
309 fc->src_data[i] = (const unsigned char *)buf;
313 /* setup data slices */
315 for (i = g->num_header_slices; i < k; i++) {
316 if (buf + slice_bytes > vsst->map + mmd->size)
318 * Can not use the memory mapped audio file for this
319 * slice as it goes beyond the map. This slice will not
323 fc->src_data[i] = (const unsigned char *)buf;
327 uint32_t payload_size = vsst->map + mmd->size - buf;
328 memcpy(fc->extra_src_buf, buf, payload_size);
329 fc->src_data[i] = fc->extra_src_buf;
331 /* use arbitrary data for all remaining slices */
334 fc->src_data[i] = (const unsigned char *)buf;
337 /* setup group timing */
338 tv_scale(g->first_chunk - fc->first_stream_chunk, chunk_tv, &tmp);
339 tv_add(&fc->stream_start, &tmp, &g->start);
340 if (g->num) /* quick hack to avoid buffer underruns */
342 tv_scale(g->num_chunks, chunk_tv, &tmp); /* group duration */
343 tv_divide(fc->fcp->slices_per_group + fc->num_extra_slices,
344 &tmp, &g->slice_duration);
346 PARA_DEBUG_LOG("FEC group %d: %d chunks (%d - %d), %d header slices, %d data slices\n",
347 g->num, g->num_chunks, g->first_chunk,
348 g->first_chunk + g->num_chunks - 1,
349 g->num_header_slices, data_slices
351 PARA_DEBUG_LOG("durations (group/chunk/slice): %lu/%lu/%lu\n",
352 tv2ms(&tmp), tv2ms(chunk_tv), tv2ms(&g->slice_duration));
356 static int compute_next_fec_slice(struct fec_client *fc, struct vss_task *vsst)
358 assert(fc->error >= 0);
359 if (fc->first_stream_chunk < 0 || fc->current_slice_num
360 == fc->fcp->slices_per_group + fc->num_extra_slices) {
361 int ret = setup_next_fec_group(fc, vsst);
365 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
366 PARA_ERROR_LOG("FEC client temporarily disabled\n");
371 write_fec_header(fc, vsst);
372 fec_encode(fc->parms, fc->src_data, fc->enc_buf + FEC_HEADER_SIZE,
373 fc->current_slice_num,
374 fc->fcp->max_slice_bytes - FEC_HEADER_SIZE);
379 * Return a buffer that marks the end of the stream.
381 * \param buf Result pointer.
382 * \return The length of the eof buffer.
384 * This is used for (multicast) udp streaming where closing the socket on the
385 * sender might not give rise to an eof condition at the peer.
387 size_t vss_get_fec_eof_packet(const char **buf)
389 static const char fec_eof_packet[FEC_HEADER_SIZE] = FEC_EOF_PACKET;
390 *buf = fec_eof_packet;
391 return FEC_HEADER_SIZE;
395 * Add one entry to the list of active fec clients.
397 * \param fcp Describes the fec parameters to be used for this client.
398 * \param result An opaque pointer that must be used by remove the client later.
402 int vss_add_fec_client(struct fec_client_parms *fcp, struct fec_client **result)
405 struct fec_client *fc;
407 if (fcp->max_slice_bytes < FEC_HEADER_SIZE + fcp->data_slices_per_group)
408 return -ERRNO_TO_PARA_ERROR(EINVAL);
409 fc = para_calloc(sizeof(*fc));
411 ret = fec_new(fcp->data_slices_per_group, fcp->slices_per_group,
415 fc->first_stream_chunk = -1; /* stream not yet started */
416 fc->src_data = para_malloc(fc->fcp->slices_per_group * sizeof(char *));
417 fc->enc_buf = para_calloc(fc->fcp->max_slice_bytes);
418 fc->num_extra_slices = 0;
419 fc->extra_src_buf = para_calloc(fc->fcp->max_slice_bytes);
420 fc->next_header_time.tv_sec = 0;
421 para_list_add(&fc->node, &fec_client_list);
432 * Remove one entry from the list of active fec clients.
434 * \param fc The client to be removed.
436 void vss_del_fec_client(struct fec_client *fc)
441 free(fc->extra_src_buf);
447 * Compute if/when next slice is due. If it isn't due yet and \a diff is
448 * not \p Null, compute the time difference next - now, where
450 * next = stream_start + (first_group_chunk - first_stream_chunk)
451 * * chunk_time + slice_num * slice_time
453 static int next_slice_is_due(struct fec_client *fc, struct timeval *diff)
455 struct timeval tmp, next;
458 if (fc->first_stream_chunk < 0)
460 tv_scale(fc->current_slice_num, &fc->group.slice_duration, &tmp);
461 tv_add(&tmp, &fc->group.start, &next);
462 ret = tv_diff(&next, now, diff);
463 return ret < 0? 1 : 0;
466 static void compute_slice_timeout(struct timeval *timeout)
468 struct fec_client *fc;
470 assert(vss_playing());
471 list_for_each_entry(fc, &fec_client_list, node) {
476 if (next_slice_is_due(fc, &diff)) {
478 timeout->tv_usec = 0;
481 /* timeout = min(timeout, diff) */
482 if (tv_diff(&diff, timeout, NULL) < 0)
487 static void set_eof_barrier(struct vss_task *vsst)
489 struct fec_client *fc;
490 struct timeval timeout = {1, 0}, *chunk_tv = vss_chunk_time();
494 list_for_each_entry(fc, &fec_client_list, node) {
495 struct timeval group_duration;
499 tv_scale(fc->group.num_chunks, chunk_tv, &group_duration);
500 if (tv_diff(&timeout, &group_duration, NULL) < 0)
501 timeout = group_duration;
504 tv_add(now, &timeout, &vsst->eof_barrier);
508 * Check if vss status flag \a P (playing) is set.
510 * \return Greater than zero if playing, zero otherwise.
513 unsigned int vss_playing(void)
515 return mmd->new_vss_status_flags & VSS_PLAYING;
519 * Check if the \a N (next) status flag is set.
521 * \return Greater than zero if set, zero if not.
524 unsigned int vss_next(void)
526 return mmd->new_vss_status_flags & VSS_NEXT;
530 * Check if a reposition request is pending.
532 * \return Greater than zero if true, zero otherwise.
535 unsigned int vss_repos(void)
537 return mmd->new_vss_status_flags & VSS_REPOS;
541 * Check if the vss is currently paused.
543 * \return Greater than zero if paused, zero otherwise.
546 unsigned int vss_paused(void)
548 return !(mmd->new_vss_status_flags & VSS_NEXT)
549 && !(mmd->new_vss_status_flags & VSS_PLAYING);
553 * Check if the vss is currently stopped.
555 * \return Greater than zero if paused, zero otherwise.
558 unsigned int vss_stopped(void)
560 return (mmd->new_vss_status_flags & VSS_NEXT)
561 && !(mmd->new_vss_status_flags & VSS_PLAYING);
564 static int chk_barrier(const char *bname, const struct timeval *barrier,
565 struct timeval *diff, int print_log)
569 if (tv_diff(now, barrier, diff) > 0)
573 PARA_DEBUG_LOG("%s barrier: %lims left\n", bname, ms);
578 * != NULL: timeout for next chunk
579 * NULL: nothing to do
581 static struct timeval *vss_compute_timeout(struct vss_task *vsst)
583 static struct timeval the_timeout;
584 struct timeval next_chunk;
586 if (vss_next() && vsst->map) {
587 /* only sleep a bit, nec*/
588 the_timeout.tv_sec = 0;
589 the_timeout.tv_usec = 100;
592 if (chk_barrier("autoplay_delay", &vsst->autoplay_barrier,
593 &the_timeout, 1) < 0)
595 if (chk_barrier("eof", &vsst->eof_barrier, &the_timeout, 1) < 0)
597 if (chk_barrier("data send", &vsst->data_send_barrier,
598 &the_timeout, 1) < 0)
600 if (!vss_playing() || !vsst->map)
602 compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
603 &mmd->stream_start, &next_chunk);
604 if (chk_barrier("chunk", &next_chunk, &the_timeout, 0) >= 0) {
605 /* chunk is due or bof */
606 the_timeout.tv_sec = 0;
607 the_timeout.tv_usec = 0;
610 /* compute min of current timeout and next slice time */
611 compute_slice_timeout(&the_timeout);
615 static void vss_eof(struct vss_task *vsst)
620 if (mmd->new_vss_status_flags & VSS_NOMORE)
621 mmd->new_vss_status_flags = VSS_NEXT;
622 set_eof_barrier(vsst);
623 para_munmap(vsst->map, mmd->size);
625 mmd->chunks_sent = 0;
627 mmd->afd.afhi.seconds_total = 0;
628 mmd->afd.afhi.chunk_tv.tv_sec = 0;
629 mmd->afd.afhi.chunk_tv.tv_usec = 0;
630 free(mmd->afd.afhi.chunk_table);
631 mmd->afd.afhi.chunk_table = NULL;
638 * Get the list of all supported audio formats.
640 * \return Aa space separated list of all supported audio formats
641 * It is not allocated at runtime, i.e. there is no need to free
642 * the returned string in the caller.
644 const char *supported_audio_formats(void)
646 return SUPPORTED_AUDIO_FORMATS;
649 static int need_to_request_new_audio_file(struct vss_task *vsst)
653 if (vsst->map) /* have audio file */
655 if (!vss_playing()) /* don't need one */
657 if (mmd->new_vss_status_flags & VSS_NOMORE)
659 if (vsst->afsss == AFS_SOCKET_AFD_PENDING) /* already requested one */
661 if (chk_barrier("autoplay_delay", &vsst->autoplay_barrier,
668 * Compute the timeout for the main select-loop of the scheduler.
670 * \param s Pointer to the server scheduler.
671 * \param t Pointer to the vss task structure.
673 * Before the timeout is computed, the current vss status flags are evaluated
674 * and acted upon by calling appropriate functions from the lower layers.
675 * Possible actions include
677 * - request a new audio file from afs,
678 * - shutdown of all senders (stop/pause command),
679 * - reposition the stream (ff/jmp command).
681 static void vss_pre_select(struct sched *s, struct task *t)
684 struct timeval *tv, diff;
685 struct vss_task *vsst = container_of(t, struct vss_task, task);
687 if (!vsst->map || vss_next() || vss_paused() || vss_repos()) {
688 struct fec_client *fc, *tmp;
689 for (i = 0; senders[i].name; i++)
690 if (senders[i].shutdown_clients)
691 senders[i].shutdown_clients();
692 list_for_each_entry_safe(fc, tmp, &fec_client_list, node) {
693 fc->first_stream_chunk = -1;
696 mmd->stream_start.tv_sec = 0;
697 mmd->stream_start.tv_usec = 0;
701 else if (vss_paused()) {
702 if (mmd->chunks_sent)
703 set_eof_barrier(vsst);
704 mmd->chunks_sent = 0;
705 } else if (vss_repos()) {
706 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
707 set_eof_barrier(vsst);
708 mmd->chunks_sent = 0;
709 mmd->current_chunk = mmd->repos_request;
710 mmd->new_vss_status_flags &= ~VSS_REPOS;
712 if (need_to_request_new_audio_file(vsst)) {
713 PARA_DEBUG_LOG("ready and playing, but no audio file\n");
714 para_fd_set(vsst->afs_socket, &s->wfds, &s->max_fileno);
715 vsst->afsss = AFS_SOCKET_CHECK_FOR_WRITE;
717 para_fd_set(vsst->afs_socket, &s->rfds, &s->max_fileno);
718 for (i = 0; senders[i].name; i++) {
719 if (!senders[i].pre_select)
721 senders[i].pre_select(&s->max_fileno, &s->rfds, &s->wfds);
723 tv = vss_compute_timeout(vsst);
724 if (tv && tv_diff(tv, &s->timeout, &diff) < 0)
728 static int recv_afs_msg(int afs_socket, int *fd, uint32_t *code, uint32_t *data)
730 char control[255], buf[8];
731 struct msghdr msg = {.msg_iov = NULL};
732 struct cmsghdr *cmsg;
738 iov.iov_len = sizeof(buf);
741 msg.msg_control = control;
742 msg.msg_controllen = sizeof(control);
743 memset(buf, 0, sizeof(buf));
744 ret = recvmsg(afs_socket, &msg, 0);
746 return -ERRNO_TO_PARA_ERROR(errno);
747 if (iov.iov_len != sizeof(buf))
748 return -E_AFS_SHORT_READ;
749 *code = *(uint32_t*)buf;
750 *data = *(uint32_t*)(buf + 4);
751 for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
752 if (cmsg->cmsg_level != SOL_SOCKET
753 || cmsg->cmsg_type != SCM_RIGHTS)
755 if ((cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int) != 1)
757 *fd = *(int *)CMSG_DATA(cmsg);
762 static void recv_afs_result(struct vss_task *vsst)
764 int ret, passed_fd, shmid;
765 uint32_t afs_code = 0, afs_data = 0;
768 vsst->afsss = AFS_SOCKET_READY;
769 ret = recv_afs_msg(vsst->afs_socket, &passed_fd, &afs_code, &afs_data);
772 PARA_DEBUG_LOG("fd: %d, code: %u, shmid: %u\n", passed_fd, afs_code,
775 if (afs_code != NEXT_AUDIO_FILE)
780 ret = load_afd(shmid, &mmd->afd);
784 ret = fstat(passed_fd, &statbuf);
786 PARA_ERROR_LOG("fstat error:\n");
787 ret = -ERRNO_TO_PARA_ERROR(errno);
790 mmd->size = statbuf.st_size;
791 mmd->mtime = statbuf.st_mtime;
792 ret = para_mmap(mmd->size, PROT_READ, MAP_PRIVATE, passed_fd,
797 mmd->chunks_sent = 0;
798 mmd->current_chunk = 0;
802 mmd->new_vss_status_flags &= (~VSS_NEXT);
803 afh_get_header(&mmd->afd.afhi, vsst->map, &vsst->header_buf,
807 free(mmd->afd.afhi.chunk_table);
810 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
811 mmd->new_vss_status_flags = VSS_NEXT;
815 * Main sending function.
817 * This function gets called from vss_post_select(). It checks whether the next
818 * chunk of data should be pushed out. It obtains a pointer to the data to be
819 * sent out as well as its length from mmd->afd.afhi. This information is then
820 * passed to each supported sender's send() function as well as to the send()
821 * functions of each registered fec client.
823 static void vss_send(struct vss_task *vsst)
825 int i, sent_something = 0;
827 struct fec_client *fc, *tmp_fc;
829 if (!vsst->map || !vss_playing())
831 if (chk_barrier("eof", &vsst->eof_barrier, &due, 1) < 0)
833 if (chk_barrier("data send", &vsst->data_send_barrier,
836 list_for_each_entry_safe(fc, tmp_fc, &fec_client_list, node) {
839 if (!next_slice_is_due(fc, NULL))
841 if (compute_next_fec_slice(fc, vsst) <= 0)
843 PARA_DEBUG_LOG("sending %d:%d (%u bytes)\n", fc->group.num,
844 fc->current_slice_num, fc->fcp->max_slice_bytes);
845 fc->fcp->send((char *)fc->enc_buf,
846 fc->fcp->max_slice_bytes,
847 fc->fcp->private_data);
848 fc->current_slice_num++;
851 if (mmd->current_chunk >= mmd->afd.afhi.chunks_total) { /* eof */
853 mmd->new_vss_status_flags |= VSS_NEXT;
856 compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
857 &mmd->stream_start, &due);
858 if (tv_diff(&due, now, NULL) <= 0) {
862 if (!mmd->chunks_sent) {
864 mmd->stream_start = *now;
865 tv_scale(mmd->current_chunk, &mmd->afd.afhi.chunk_tv, &tmp);
866 mmd->offset = tv2ms(&tmp);
870 * We call the send function also in case of empty chunks as
871 * they might have still some data queued which can be sent in
874 afh_get_chunk(mmd->current_chunk, &mmd->afd.afhi, vsst->map,
876 for (i = 0; senders[i].name; i++) {
877 if (!senders[i].send)
879 senders[i].send(mmd->current_chunk, mmd->chunks_sent,
880 buf, len, vsst->header_buf, vsst->header_len);
883 mmd->current_chunk++;
887 static void vss_post_select(struct sched *s, struct task *t)
890 struct vss_task *vsst = container_of(t, struct vss_task, task);
893 if (mmd->sender_cmd_data.cmd_num >= 0) {
894 int num = mmd->sender_cmd_data.cmd_num,
895 sender_num = mmd->sender_cmd_data.sender_num;
897 if (senders[sender_num].client_cmds[num])
898 senders[sender_num].client_cmds[num](&mmd->sender_cmd_data);
899 mmd->sender_cmd_data.cmd_num = -1;
901 if (vsst->afsss != AFS_SOCKET_CHECK_FOR_WRITE) {
902 if (FD_ISSET(vsst->afs_socket, &s->rfds))
903 recv_afs_result(vsst);
904 } else if (FD_ISSET(vsst->afs_socket, &s->wfds)) {
905 PARA_NOTICE_LOG("requesting new fd from afs\n");
906 ret = send_buffer(vsst->afs_socket, "new");
908 PARA_CRIT_LOG("%s\n", para_strerror(-ret));
910 vsst->afsss = AFS_SOCKET_AFD_PENDING;
912 for (i = 0; senders[i].name; i++) {
913 if (!senders[i].post_select)
915 senders[i].post_select(&s->rfds, &s->wfds);
917 if ((vss_playing() && !(mmd->vss_status_flags & VSS_PLAYING)) ||
918 (vss_next() && vss_playing()))
919 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
924 * Initialize the virtual streaming system task.
926 * \param afs_socket The fd for communication with afs.
928 * This also initializes all supported senders and starts streaming
929 * if the --autoplay command line flag was given.
931 void init_vss_task(int afs_socket)
933 static struct vss_task vss_task_struct, *vsst = &vss_task_struct;
935 char *hn = para_hostname(), *home = para_homedir();
936 long unsigned announce_time = conf.announce_time_arg > 0?
937 conf.announce_time_arg : 300,
938 autoplay_delay = conf.autoplay_delay_arg > 0?
939 conf.autoplay_delay_arg : 0;
940 vsst->header_interval.tv_sec = 5; /* should this be configurable? */
941 vsst->afs_socket = afs_socket;
942 vsst->task.pre_select = vss_pre_select;
943 vsst->task.post_select = vss_post_select;
944 ms2tv(announce_time, &vsst->announce_tv);
945 PARA_INFO_LOG("announce timeval: %lums\n", tv2ms(&vsst->announce_tv));
946 INIT_LIST_HEAD(&fec_client_list);
947 for (i = 0; senders[i].name; i++) {
948 PARA_NOTICE_LOG("initializing %s sender\n", senders[i].name);
949 senders[i].init(&senders[i]);
953 mmd->sender_cmd_data.cmd_num = -1;
954 if (conf.autoplay_given) {
956 mmd->vss_status_flags |= VSS_PLAYING;
957 mmd->new_vss_status_flags |= VSS_PLAYING;
958 ms2tv(autoplay_delay, &tmp);
959 tv_add(now, &tmp, &vsst->autoplay_barrier);
960 tv_add(&vsst->autoplay_barrier, &vsst->announce_tv,
961 &vsst->data_send_barrier);
963 register_task(&vsst->task);