1 /* Copyright (C) 1997 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
3 /** \file vss.c The virtual streaming system.
5 * This contains the audio streaming code of para_server which is independent
6 * of the current audio format, audio file selector and of the activated
10 #include <sys/socket.h>
11 #include <netinet/in.h>
14 #include <sys/types.h>
15 #include <arpa/inet.h>
20 #include "server.lsg.h"
23 #include "portable_io.h"
37 extern struct misc_meta_data *mmd;
39 extern void dccp_send_init(struct sender *);
40 extern void http_send_init(struct sender *);
41 extern void udp_send_init(struct sender *);
43 extern const struct sender udp_sender, dccp_sender, http_sender;
44 const struct sender * const senders[] = {
45 &http_sender, &dccp_sender, &udp_sender, NULL};
47 /** The possible states of the afs socket. */
48 enum afs_socket_status {
49 /** Socket is inactive. */
51 /** Socket fd was included in the write fd set for select(). */
52 AFS_SOCKET_CHECK_FOR_WRITE,
53 /** vss wrote a request to the socket and waits for reply from afs. */
54 AFS_SOCKET_AFD_PENDING
57 /** The task structure for the virtual streaming system. */
59 /** Copied from the -announce_time command line option. */
60 struct timeval announce_tv;
61 /** End of the announcing interval. */
62 struct timeval data_send_barrier;
63 /** End of the EOF interval. */
64 struct timeval eof_barrier;
65 /** Only used if --autoplay_delay was given. */
66 struct timeval autoplay_barrier;
67 /** Used for afs-server communication. */
69 /** The current state of \a afs_socket. */
70 enum afs_socket_status afsss;
71 /** The memory mapped audio file. */
73 /** The size of the memory mapping. */
75 /** Used by the scheduler. */
77 /** Pointer to the header of the mapped audio file. */
79 /** Length of the audio file header. */
81 /** Time between audio file headers are sent. */
82 struct timeval header_interval;
83 /* Only used if afh supports dynamic chunks. */
88 * The list of currently connected fec clients.
90 * Senders may use \ref vss_add_fec_client() to add entries to the list.
92 static struct list_head fec_client_list;
95 * Data associated with one FEC group.
97 * A FEC group consists of a fixed number of slices and this number is given by
98 * the \a slices_per_group parameter of struct \ref fec_client_parms. Each FEC
99 * group contains a number of chunks of the current audio file.
101 * FEC slices directly correspond to the data packages sent by the paraslash
102 * senders that use FEC. Each slice is identified by its group number and its
103 * number within the group. All slices have the same size, but the last slice
104 * of the group may not be filled entirely.
107 /** The number of the FEC group. */
109 /** Number of bytes in this group. */
111 /** The first chunk of the current audio file belonging to the group. */
112 uint32_t first_chunk;
113 /** The number of chunks contained in this group. */
115 /** When the first chunk was sent. */
116 struct timeval start;
117 /** The duration of the full group. */
118 struct timeval duration;
119 /** The group duration divided by the number of slices. */
120 struct timeval slice_duration;
121 /** Group contains the audio file header that occupies that many slices. */
122 uint8_t num_header_slices;
123 /** Number of bytes per slice for this group. */
124 uint16_t slice_bytes;
127 /** A FEC client is always in one of these states. */
128 enum fec_client_state {
129 FEC_STATE_NONE = 0, /**< not initialized and not enabled */
130 FEC_STATE_DISABLED, /**< temporarily disabled */
131 FEC_STATE_READY_TO_RUN /**< initialized and enabled */
135 * Describes one connected FEC client.
138 /** Current state of the client */
139 enum fec_client_state state;
140 /** The connected sender client (transport layer). */
141 struct sender_client *sc;
142 /** Parameters requested by the client. */
143 struct fec_client_parms *fcp;
144 /** Used by the core FEC code. */
145 struct fec_parms *parms;
146 /** The position of this client in the fec client list. */
147 struct list_head node;
148 /** When the first slice for this client was sent. */
149 struct timeval stream_start;
150 /** The first chunk sent to this FEC client. */
151 int first_stream_chunk;
152 /** Describes the current group. */
153 struct fec_group group;
154 /** The current slice. */
155 uint8_t current_slice_num;
156 /** The data to be FEC-encoded (point to a region within the mapped audio file). */
157 const unsigned char **src_data;
158 /** Last time an audio header was sent. */
159 struct timeval next_header_time;
160 /** Used for the last source pointer of an audio file. */
161 unsigned char *extra_src_buf;
162 /** Needed for the last slice of the audio file header. */
163 unsigned char *extra_header_buf;
164 /** Extra slices needed to store largest chunk + header. */
165 int num_extra_slices;
166 /** Contains the FEC-encoded data. */
167 unsigned char *enc_buf;
168 /** Maximal packet size. */
173 * Get the chunk time of the current audio file.
175 * \return A pointer to a struct containing the chunk time, or NULL,
176 * if currently no audio file is selected.
178 struct timeval *vss_chunk_time(void)
180 if (mmd->afd.afhi.chunk_tv.tv_sec == 0 &&
181 mmd->afd.afhi.chunk_tv.tv_usec == 0)
183 return &mmd->afd.afhi.chunk_tv;
187 * Write a fec header to a buffer.
189 * \param buf The buffer to write to.
190 * \param h The fec header to write.
192 static void write_fec_header(struct fec_client *fc, struct vss_task *vsst)
194 char *buf = (char *)fc->enc_buf;
195 struct fec_group *g = &fc->group;
196 struct fec_client_parms *p = fc->fcp;
198 write_u32(buf, FEC_MAGIC);
200 write_u8(buf + 4, p->slices_per_group + fc->num_extra_slices);
201 write_u8(buf + 5, p->data_slices_per_group + fc->num_extra_slices);
202 write_u32(buf + 6, g->num_header_slices? vsst->header_len : 0);
204 write_u32(buf + 10, g->num);
205 write_u32(buf + 14, g->bytes);
207 write_u8(buf + 18, fc->current_slice_num);
208 write_u8(buf + 19, 0); /* unused */
209 write_u16(buf + 20, g->slice_bytes);
210 write_u8(buf + 22, g->first_chunk? 0 : 1);
211 write_u8(buf + 23, vsst->header_len? 1 : 0);
212 memset(buf + 24, 0, 8);
215 static bool need_audio_header(struct fec_client *fc, struct vss_task *vsst)
217 if (!mmd->current_chunk) {
218 tv_add(now, &vsst->header_interval, &fc->next_header_time);
221 if (!vsst->header_buf)
223 if (vsst->header_len == 0)
225 if (fc->group.num > 0) {
226 if (!fc->fcp->need_periodic_header)
228 if (tv_diff(&fc->next_header_time, now, NULL) > 0)
231 tv_add(now, &vsst->header_interval, &fc->next_header_time);
235 static bool need_data_slices(struct fec_client *fc, struct vss_task *vsst)
237 if (fc->group.num > 0)
239 if (!vsst->header_buf)
241 if (vsst->header_len == 0)
243 if (fc->fcp->need_periodic_header)
248 static int num_slices(long unsigned bytes, int max_payload, int rs)
252 assert(max_payload > 0);
254 ret = DIV_ROUND_UP(bytes, max_payload);
260 /* set group start and group duration */
261 static void set_group_timing(struct fec_client *fc, struct vss_task *vsst)
263 struct fec_group *g = &fc->group;
264 struct timeval *chunk_tv = vss_chunk_time();
266 if (!need_data_slices(fc, vsst))
267 ms2tv(200, &g->duration);
269 tv_scale(g->num_chunks, chunk_tv, &g->duration);
270 tv_divide(fc->fcp->slices_per_group + fc->num_extra_slices,
271 &g->duration, &g->slice_duration);
272 PARA_DEBUG_LOG("durations (group/chunk/slice): %lu/%lu/%lu\n",
273 tv2ms(&g->duration), tv2ms(chunk_tv), tv2ms(&g->slice_duration));
276 static int initialize_fec_client(struct fec_client *fc, struct vss_task *vsst)
279 int hs, ds, rs; /* header/data/redundant slices */
280 struct fec_client_parms *fcp = fc->fcp;
285 * Set the maximum slice size to the Maximum Packet Size if the
286 * transport protocol allows determination of this value. The user
287 * can specify a slice size up to this value.
289 ret = fcp->init_fec(fc->sc);
294 fc->mps = generic_max_transport_msg_size(fc->sc->fd);
295 if (fc->mps <= FEC_HEADER_SIZE)
296 return -ERRNO_TO_PARA_ERROR(EINVAL);
298 rs = fc->fcp->slices_per_group - fc->fcp->data_slices_per_group;
299 ret = num_slices(vsst->header_len, fc->mps - FEC_HEADER_SIZE, rs);
303 ret = num_slices(mmd->afd.max_chunk_size, fc->mps - FEC_HEADER_SIZE, rs);
307 if (fc->fcp->need_periodic_header)
310 k = PARA_MAX(hs, ds);
311 if (k < fc->fcp->data_slices_per_group)
312 k = fc->fcp->data_slices_per_group;
313 fc->num_extra_slices = k - fc->fcp->data_slices_per_group;
316 ret = fec_new(k, n, &fc->parms);
319 PARA_INFO_LOG("mps: %d, k: %d, n: %d, extra slices: %d\n",
320 fc->mps, k, n, fc->num_extra_slices);
321 fc->src_data = para_realloc(fc->src_data, k * sizeof(char *));
322 fc->enc_buf = para_realloc(fc->enc_buf, fc->mps);
323 fc->extra_src_buf = para_realloc(fc->extra_src_buf, fc->mps);
324 fc->extra_header_buf = para_realloc(fc->extra_header_buf, fc->mps);
326 fc->state = FEC_STATE_READY_TO_RUN;
327 fc->next_header_time.tv_sec = 0;
328 fc->stream_start = *now;
329 fc->first_stream_chunk = mmd->current_chunk;
333 static int vss_get_chunk(int chunk_num, struct vss_task *vsst,
334 char **buf, size_t *sz)
339 * Chunk zero is special for header streams: It is the first portion of
340 * the audio file which consists of the audio file header. It may be
341 * arbitrary large due to embedded meta data. Audio format handlers may
342 * replace the header by a stripped one with meta data omitted which is
343 * of bounded size. We always use the stripped header for streaming
344 * rather than the unmodified header (chunk zero).
346 if (chunk_num == 0 && vsst->header_len > 0) {
347 assert(vsst->header_buf);
348 *buf = vsst->header_buf; /* stripped header */
349 *sz = vsst->header_len;
352 ret = afh_get_chunk(chunk_num, &mmd->afd.afhi,
353 mmd->afd.audio_format_id, vsst->map, vsst->mapsize,
354 (const char **)buf, sz, &vsst->afh_context);
362 static int compute_group_size(struct vss_task *vsst, struct fec_group *g,
367 int ret, i, max_chunks = PARA_MAX(1LU, 150 / tv2ms(vss_chunk_time()));
369 if (g->first_chunk == 0) {
371 ret = vss_get_chunk(0, vsst, &buf, &len);
381 * Include chunks into the group until the group duration is at least
382 * 150ms. For ogg and wma, a single chunk's duration (ogg page/wma
383 * super frame) is already larger than 150ms, so a FEC group consists
384 * of exactly one chunk for these audio formats.
387 int chunk_num = g->first_chunk + i;
389 if (g->bytes > 0 && i >= max_chunks) /* duration limit */
391 if (chunk_num >= mmd->afd.afhi.chunks_total) /* eof */
393 ret = vss_get_chunk(chunk_num, vsst, &buf, &len);
396 if (g->bytes + len > max_bytes)
398 /* Include this chunk */
402 assert(g->num_chunks);
407 * Compute the slice size of the next group.
409 * The FEC parameters n and k are fixed but the slice size varies per
410 * FEC group. We'd like to choose slices as small as possible to avoid
411 * unnecessary FEC calculations but large enough to guarantee that the
412 * k data slices suffice to encode the header (if needed) and the data
415 * Once we know the payload of the next group, we define the number s
416 * of bytes per slice for this group by
418 * s = ceil(payload / k)
420 * However, for header streams, computing s is more complicated since no
421 * overlapping of header and data slices is possible. Hence we have k >=
422 * 2 and s must satisfy
424 * (*) ceil(h / s) + ceil(d / s) <= k
426 * where h and d are payload of the header and the data chunk(s)
427 * respectively. In general there is no value for s such that (*)
428 * becomes an equality, for example if h = 4000, d = 5000 and k = 10.
430 * We use the following approach for computing a suitable value for s:
433 * k1 := ceil(k * min(h, d) / (h + d)),
436 * Note that k >= 2 implies k1 > 0 and k2 > 0, so
438 * s := max(ceil(min(h, d) / k1), ceil(max(h, d) / k2))
440 * is well-defined. Inequality (*) holds for this value of s since k1
441 * slices suffice to store min(h, d) while k2 slices suffice to store
442 * max(h, d), i.e. the first addent of (*) is bounded by k1 and the
445 * For the above example we obtain
447 * k1 = ceil(10 * 4000 / 9000) = 5, k2 = 5,
448 * s = max(4000 / 5, 5000 / 5) = 1000,
450 * which is optimal since a slice size of 999 bytes would already require
453 static int compute_slice_size(struct fec_client *fc, struct vss_task *vsst)
455 struct fec_group *g = &fc->group;
456 int k = fc->fcp->data_slices_per_group + fc->num_extra_slices;
457 int n = fc->fcp->slices_per_group + fc->num_extra_slices;
458 int ret, k1, k2, h, d, min, max, sum;
459 int max_slice_bytes = fc->mps - FEC_HEADER_SIZE;
462 if (!need_audio_header(fc, vsst)) {
463 max_group_bytes = k * max_slice_bytes;
464 g->num_header_slices = 0;
465 ret = compute_group_size(vsst, g, max_group_bytes);
468 g->slice_bytes = DIV_ROUND_UP(g->bytes, k);
469 if (g->slice_bytes == 0)
473 if (!need_data_slices(fc, vsst)) {
476 g->slice_bytes = DIV_ROUND_UP(vsst->header_len, k);
477 g->num_header_slices = k;
480 h = vsst->header_len;
481 max_group_bytes = (k - num_slices(h, max_slice_bytes, n - k))
483 ret = compute_group_size(vsst, g, max_group_bytes);
488 g->slice_bytes = DIV_ROUND_UP(h, k);
489 ret = num_slices(vsst->header_len, g->slice_bytes, n - k);
492 g->num_header_slices = ret;
495 min = PARA_MIN(h, d);
496 max = PARA_MAX(h, d);
498 k1 = DIV_ROUND_UP(k * min, sum);
503 g->slice_bytes = PARA_MAX(DIV_ROUND_UP(min, k1), DIV_ROUND_UP(max, k2));
505 * This value of s := g->slice_bytes satisfies inequality (*) above,
506 * but it might be larger than max_slice_bytes. However, we know that
507 * max_slice_bytes are sufficient to store header and data, so:
509 g->slice_bytes = PARA_MIN((int)g->slice_bytes, max_slice_bytes);
511 ret = num_slices(vsst->header_len, g->slice_bytes, n - k);
514 g->num_header_slices = ret;
518 static int setup_next_fec_group(struct fec_client *fc, struct vss_task *vsst)
520 int ret, i, k, n, data_slices;
523 struct fec_group *g = &fc->group;
525 if (fc->state == FEC_STATE_NONE) {
526 ret = initialize_fec_client(fc, vsst);
529 g->first_chunk = mmd->current_chunk;
534 if (g->first_chunk + g->num_chunks >= mmd->afd.afhi.chunks_total)
537 * Start and duration of this group depend only on the previous
538 * group. Compute the new group start as g->start += g->duration.
541 tv_add(&tmp, &g->duration, &g->start);
542 set_group_timing(fc, vsst);
543 g->first_chunk += g->num_chunks;
546 k = fc->fcp->data_slices_per_group + fc->num_extra_slices;
547 n = fc->fcp->slices_per_group + fc->num_extra_slices;
549 compute_slice_size(fc, vsst);
550 assert(g->slice_bytes > 0);
551 ret = num_slices(g->bytes, g->slice_bytes, n - k);
555 assert(g->num_header_slices + data_slices <= k);
556 fc->current_slice_num = 0;
558 set_group_timing(fc, vsst);
559 /* setup header slices */
560 buf = vsst->header_buf;
561 for (i = 0; i < g->num_header_slices; i++) {
562 uint32_t payload_size;
563 if (buf + g->slice_bytes <= vsst->header_buf + vsst->header_len) {
564 fc->src_data[i] = (const unsigned char *)buf;
565 buf += g->slice_bytes;
569 * Can not use vss->header_buf for this slice as it
570 * goes beyond the buffer. This slice will not be fully
573 payload_size = vsst->header_buf + vsst->header_len - buf;
574 memcpy(fc->extra_header_buf, buf, payload_size);
575 if (payload_size < g->slice_bytes)
576 memset(fc->extra_header_buf + payload_size, 0,
577 g->slice_bytes - payload_size);
579 * There might be more than one header slice to fill although
580 * only the first one will be used. Set all header slices to
583 while (i < g->num_header_slices)
584 fc->src_data[i++] = fc->extra_header_buf;
585 break; /* we don't want i to be increased. */
589 * Setup data slices. Note that for ogg streams chunk 0 points to a
590 * buffer on the heap rather than to the mapped audio file.
592 ret = vss_get_chunk(g->first_chunk, vsst, &buf, &len);
595 for (p = buf; i < g->num_header_slices + data_slices; i++) {
596 if (p + g->slice_bytes > buf + g->bytes) {
598 * We must make a copy for this slice since using p
599 * directly would exceed the buffer.
601 uint32_t payload_size = buf + g->bytes - p;
602 assert(payload_size + FEC_HEADER_SIZE <= fc->mps);
603 memcpy(fc->extra_src_buf, p, payload_size);
604 if (payload_size < g->slice_bytes)
605 memset(fc->extra_src_buf + payload_size, 0,
606 g->slice_bytes - payload_size);
607 fc->src_data[i] = fc->extra_src_buf;
611 fc->src_data[i] = (const unsigned char *)p;
615 /* use arbitrary data for all remaining slices */
618 fc->src_data[i] = (const unsigned char *)buf;
620 PARA_DEBUG_LOG("FEC group %u: %u chunks (%u - %u), %u bytes\n",
621 g->num, g->num_chunks, g->first_chunk,
622 g->first_chunk + g->num_chunks - 1, g->bytes
624 PARA_DEBUG_LOG("slice_bytes: %d, %d header slices, %d data slices\n",
625 g->slice_bytes, g->num_header_slices, data_slices
630 static int compute_next_fec_slice(struct fec_client *fc, struct vss_task *vsst)
632 if (fc->state == FEC_STATE_NONE || fc->current_slice_num
633 == fc->fcp->slices_per_group + fc->num_extra_slices) {
634 int ret = setup_next_fec_group(fc, vsst);
638 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
639 PARA_ERROR_LOG("FEC client temporarily disabled\n");
640 fc->state = FEC_STATE_DISABLED;
644 write_fec_header(fc, vsst);
645 fec_encode(fc->parms, fc->src_data, fc->enc_buf + FEC_HEADER_SIZE,
646 fc->current_slice_num, fc->group.slice_bytes);
651 * Return a buffer that marks the end of the stream.
653 * \param buf Result pointer.
654 * \return The length of the eof buffer.
656 * This is used for (multicast) udp streaming where closing the socket on the
657 * sender might not give rise to an eof condition at the peer.
659 size_t vss_get_fec_eof_packet(const char **buf)
661 static const char fec_eof_packet[FEC_HEADER_SIZE] = FEC_EOF_PACKET;
662 *buf = fec_eof_packet;
663 return FEC_HEADER_SIZE;
667 * Add one entry to the list of active fec clients.
669 * \param sc Generic sender_client data of the transport layer.
670 * \param fcp FEC parameters as supplied by the transport layer.
672 * \return Newly allocated fec_client struct.
674 struct fec_client *vss_add_fec_client(struct sender_client *sc,
675 struct fec_client_parms *fcp)
677 struct fec_client *fc = para_calloc(sizeof(*fc));
681 para_list_add(&fc->node, &fec_client_list);
686 * Remove one entry from the list of active fec clients.
688 * \param fc The client to be removed.
690 void vss_del_fec_client(struct fec_client *fc)
695 free(fc->extra_src_buf);
696 free(fc->extra_header_buf);
702 * Compute if/when next slice is due. If it isn't due yet and \a diff is
703 * not \p Null, compute the time difference next - now, where
705 * next = stream_start + (first_group_chunk - first_stream_chunk)
706 * * chunk_time + slice_num * slice_time
708 static int next_slice_is_due(struct fec_client *fc, struct timeval *diff)
710 struct timeval tmp, next;
713 if (fc->state == FEC_STATE_NONE)
715 tv_scale(fc->current_slice_num, &fc->group.slice_duration, &tmp);
716 tv_add(&tmp, &fc->group.start, &next);
717 ret = tv_diff(&next, now, diff);
718 return ret < 0? 1 : 0;
721 static void set_eof_barrier(struct vss_task *vsst)
723 struct fec_client *fc;
724 struct timeval timeout = {1, 0}, *chunk_tv = vss_chunk_time();
728 list_for_each_entry(fc, &fec_client_list, node) {
729 struct timeval group_duration;
731 if (fc->state != FEC_STATE_READY_TO_RUN)
733 tv_scale(fc->group.num_chunks, chunk_tv, &group_duration);
734 if (tv_diff(&timeout, &group_duration, NULL) < 0)
735 timeout = group_duration;
738 tv_add(now, &timeout, &vsst->eof_barrier);
742 * Check if vss status flag \a P (playing) is set.
744 * \return Greater than zero if playing, zero otherwise.
747 unsigned int vss_playing(void)
749 return mmd->new_vss_status_flags & VSS_PLAYING;
753 * Check if the \a N (next) status flag is set.
755 * \return Greater than zero if set, zero if not.
758 unsigned int vss_next(void)
760 return mmd->new_vss_status_flags & VSS_NEXT;
764 * Check if a reposition request is pending.
766 * \return Greater than zero if true, zero otherwise.
769 unsigned int vss_repos(void)
771 return mmd->new_vss_status_flags & VSS_REPOS;
775 * Check if the vss is currently paused.
777 * \return Greater than zero if paused, zero otherwise.
780 unsigned int vss_paused(void)
782 return !(mmd->new_vss_status_flags & VSS_NEXT)
783 && !(mmd->new_vss_status_flags & VSS_PLAYING);
787 * Check if the vss is currently stopped.
789 * \return Greater than zero if paused, zero otherwise.
792 unsigned int vss_stopped(void)
794 return (mmd->new_vss_status_flags & VSS_NEXT)
795 && !(mmd->new_vss_status_flags & VSS_PLAYING);
798 static int chk_barrier(const char *bname, const struct timeval *barrier,
799 struct timeval *diff, int print_log)
803 if (tv_diff(now, barrier, diff) > 0)
807 PARA_DEBUG_LOG("%s barrier: %lims left\n", bname, ms);
811 static void vss_compute_timeout(struct sched *s, struct vss_task *vsst)
814 struct fec_client *fc;
816 if (!vss_playing() || !vsst->map)
818 if (vss_next() && vsst->map) /* only sleep a bit, nec*/
819 return sched_request_timeout_ms(100, s);
821 /* Each of these barriers must have passed until we may proceed */
822 if (sched_request_barrier(&vsst->autoplay_barrier, s) == 1)
824 if (sched_request_barrier(&vsst->eof_barrier, s) == 1)
826 if (sched_request_barrier(&vsst->data_send_barrier, s) == 1)
829 * Compute the select timeout as the minimal time until the next
830 * chunk/slice is due for any client.
832 compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
833 &mmd->stream_start, &tv);
834 if (sched_request_barrier_or_min_delay(&tv, s) == 0)
836 list_for_each_entry(fc, &fec_client_list, node) {
837 if (fc->state != FEC_STATE_READY_TO_RUN)
839 if (next_slice_is_due(fc, &tv))
840 return sched_min_delay(s);
841 sched_request_timeout(&tv, s);
845 static void vss_eof(struct vss_task *vsst)
850 if (mmd->new_vss_status_flags & VSS_NOMORE)
851 mmd->new_vss_status_flags = VSS_NEXT;
852 set_eof_barrier(vsst);
853 afh_free_header(vsst->header_buf, mmd->afd.audio_format_id);
854 vsst->header_buf = NULL;
855 para_munmap(vsst->map, vsst->mapsize);
857 mmd->chunks_sent = 0;
859 mmd->afd.afhi.seconds_total = 0;
860 mmd->afd.afhi.chunk_tv.tv_sec = 0;
861 mmd->afd.afhi.chunk_tv.tv_usec = 0;
862 free(mmd->afd.afhi.chunk_table);
863 mmd->afd.afhi.chunk_table = NULL;
865 afh_close(vsst->afh_context, mmd->afd.audio_format_id);
866 vsst->afh_context = NULL;
870 static int need_to_request_new_audio_file(struct vss_task *vsst)
874 if (vsst->map) /* have audio file */
876 if (!vss_playing()) /* don't need one */
878 if (mmd->new_vss_status_flags & VSS_NOMORE)
880 if (vsst->afsss == AFS_SOCKET_AFD_PENDING) /* already requested one */
882 if (chk_barrier("autoplay_delay", &vsst->autoplay_barrier,
888 static void set_mmd_offset(void)
890 struct timeval offset;
891 tv_scale(mmd->current_chunk, &mmd->afd.afhi.chunk_tv, &offset);
892 mmd->offset = tv2ms(&offset);
895 static void vss_pre_select(struct sched *s, void *context)
898 struct vss_task *vsst = context;
900 if (need_to_request_new_audio_file(vsst)) {
901 PARA_DEBUG_LOG("ready and playing, but no audio file\n");
902 para_fd_set(vsst->afs_socket, &s->wfds, &s->max_fileno);
903 vsst->afsss = AFS_SOCKET_CHECK_FOR_WRITE;
905 para_fd_set(vsst->afs_socket, &s->rfds, &s->max_fileno);
907 if (!senders[i]->pre_select)
909 senders[i]->pre_select(&s->max_fileno, &s->rfds, &s->wfds);
911 vss_compute_timeout(s, vsst);
914 static int recv_afs_msg(int afs_socket, int *fd, uint32_t *code, uint32_t *data)
916 char control[255] __a_aligned(8), buf[8];
917 struct msghdr msg = {.msg_iov = NULL};
918 struct cmsghdr *cmsg;
924 iov.iov_len = sizeof(buf);
927 msg.msg_control = control;
928 msg.msg_controllen = sizeof(control);
929 memset(buf, 0, sizeof(buf));
930 ret = recvmsg(afs_socket, &msg, 0);
932 return -ERRNO_TO_PARA_ERROR(errno);
933 if (iov.iov_len != sizeof(buf))
934 return -E_AFS_SHORT_READ;
935 *code = *(uint32_t*)buf;
936 *data = *(uint32_t*)(buf + 4);
937 for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
938 if (cmsg->cmsg_level != SOL_SOCKET
939 || cmsg->cmsg_type != SCM_RIGHTS)
941 if ((cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int) != 1)
943 *fd = *(int *)CMSG_DATA(cmsg);
949 #define MAP_POPULATE 0
952 static void recv_afs_result(struct vss_task *vsst, fd_set *rfds)
954 int ret, passed_fd, shmid;
955 uint32_t afs_code = 0, afs_data = 0;
958 if (!FD_ISSET(vsst->afs_socket, rfds))
960 ret = recv_afs_msg(vsst->afs_socket, &passed_fd, &afs_code, &afs_data);
961 if (ret == -ERRNO_TO_PARA_ERROR(EAGAIN))
965 vsst->afsss = AFS_SOCKET_READY;
966 PARA_DEBUG_LOG("fd: %d, code: %u, shmid: %u\n", passed_fd, afs_code,
969 if (afs_code != NEXT_AUDIO_FILE)
974 ret = load_afd(shmid, &mmd->afd);
978 ret = fstat(passed_fd, &statbuf);
980 PARA_ERROR_LOG("fstat error:\n");
981 ret = -ERRNO_TO_PARA_ERROR(errno);
984 ret = para_mmap(statbuf.st_size, PROT_READ, MAP_PRIVATE | MAP_POPULATE,
985 passed_fd, &vsst->map);
988 vsst->mapsize = statbuf.st_size;
990 mmd->chunks_sent = 0;
991 mmd->current_chunk = 0;
995 mmd->new_vss_status_flags &= (~VSS_NEXT);
996 afh_get_header(&mmd->afd.afhi, mmd->afd.audio_format_id,
997 vsst->map, vsst->mapsize, &vsst->header_buf, &vsst->header_len);
1000 free(mmd->afd.afhi.chunk_table);
1003 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
1004 mmd->new_vss_status_flags = VSS_NEXT;
1008 * Main sending function.
1010 * This function gets called from vss_post_select(). It checks whether the next
1011 * chunk of data should be pushed out. It obtains a pointer to the data to be
1012 * sent out as well as its length from mmd->afd.afhi. This information is then
1013 * passed to each supported sender's send() function as well as to the send()
1014 * functions of each registered fec client.
1016 static void vss_send(struct vss_task *vsst)
1019 bool fec_active = false;
1021 struct fec_client *fc, *tmp_fc;
1025 if (!vsst->map || !vss_playing())
1027 if (chk_barrier("eof", &vsst->eof_barrier, &due, 1) < 0)
1029 if (chk_barrier("data send", &vsst->data_send_barrier, &due, 1) < 0)
1031 list_for_each_entry_safe(fc, tmp_fc, &fec_client_list, node) {
1032 if (fc->state == FEC_STATE_DISABLED)
1034 if (!next_slice_is_due(fc, NULL)) {
1038 if (compute_next_fec_slice(fc, vsst) <= 0)
1040 PARA_DEBUG_LOG("sending %u:%u (%u bytes)\n", fc->group.num,
1041 fc->current_slice_num, fc->group.slice_bytes);
1042 fc->current_slice_num++;
1043 fc->fcp->send_fec(fc->sc, (char *)fc->enc_buf,
1044 fc->group.slice_bytes + FEC_HEADER_SIZE);
1047 if (mmd->current_chunk >= mmd->afd.afhi.chunks_total) { /* eof */
1049 mmd->new_vss_status_flags |= VSS_NEXT;
1052 compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
1053 &mmd->stream_start, &due);
1054 if (tv_diff(&due, now, NULL) > 0)
1056 if (!mmd->chunks_sent) {
1057 mmd->stream_start = *now;
1061 ret = vss_get_chunk(mmd->current_chunk, vsst, &buf, &len);
1063 PARA_ERROR_LOG("could not get chunk %lu: %s\n",
1064 mmd->current_chunk, para_strerror(-ret));
1067 * We call ->send() even if len is zero because senders might
1068 * have data queued which can be sent now.
1070 FOR_EACH_SENDER(i) {
1071 if (!senders[i]->send)
1073 senders[i]->send(mmd->current_chunk, mmd->chunks_sent,
1074 buf, len, vsst->header_buf, vsst->header_len);
1078 mmd->current_chunk++;
1081 static int vss_post_select(struct sched *s, void *context)
1084 struct vss_task *vsst = context;
1086 ret = task_get_notification(vsst->task);
1088 afh_free_header(vsst->header_buf, mmd->afd.audio_format_id);
1091 if (!vsst->map || vss_next() || vss_paused() || vss_repos()) {
1092 /* shut down senders and fec clients */
1093 struct fec_client *fc, *tmp;
1095 if (senders[i]->shutdown_clients)
1096 senders[i]->shutdown_clients();
1097 list_for_each_entry_safe(fc, tmp, &fec_client_list, node)
1098 fc->state = FEC_STATE_NONE;
1099 mmd->stream_start.tv_sec = 0;
1100 mmd->stream_start.tv_usec = 0;
1104 else if (vss_paused()) {
1105 if (mmd->chunks_sent)
1106 set_eof_barrier(vsst);
1107 mmd->chunks_sent = 0;
1108 } else if (vss_repos()) { /* repositioning due to ff/jmp command */
1109 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
1110 set_eof_barrier(vsst);
1111 mmd->chunks_sent = 0;
1112 mmd->current_chunk = afh_get_start_chunk(mmd->repos_request,
1113 &mmd->afd.afhi, mmd->afd.audio_format_id);
1114 mmd->new_vss_status_flags &= ~VSS_REPOS;
1117 /* If a sender command is pending, run it. */
1118 if (mmd->sender_cmd_data.cmd_num >= 0) {
1119 int num = mmd->sender_cmd_data.cmd_num,
1120 sender_num = mmd->sender_cmd_data.sender_num;
1122 if (senders[sender_num]->client_cmds[num]) {
1123 ret = senders[sender_num]->client_cmds[num]
1124 (&mmd->sender_cmd_data);
1126 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
1128 mmd->sender_cmd_data.cmd_num = -1;
1130 if (vsst->afsss != AFS_SOCKET_CHECK_FOR_WRITE)
1131 recv_afs_result(vsst, &s->rfds);
1132 else if (FD_ISSET(vsst->afs_socket, &s->wfds)) {
1133 PARA_NOTICE_LOG("requesting new fd from afs\n");
1134 ret = write_buffer(vsst->afs_socket, "new");
1136 PARA_CRIT_LOG("%s\n", para_strerror(-ret));
1138 vsst->afsss = AFS_SOCKET_AFD_PENDING;
1140 FOR_EACH_SENDER(i) {
1141 if (!senders[i]->post_select)
1143 senders[i]->post_select(&s->rfds, &s->wfds);
1145 if ((vss_playing() && !(mmd->vss_status_flags & VSS_PLAYING)) ||
1146 (vss_next() && vss_playing()))
1147 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
1153 * Initialize the virtual streaming system task.
1155 * \param afs_socket The fd for communication with afs.
1156 * \param s The scheduler to register the vss task to.
1158 * This also initializes all supported senders and starts streaming
1159 * if the --autoplay command line flag was given.
1161 void vss_init(int afs_socket, struct sched *s)
1163 static struct vss_task vss_task_struct, *vsst = &vss_task_struct;
1165 long unsigned announce_time = OPT_UINT32_VAL(ANNOUNCE_TIME),
1166 autoplay_delay = OPT_UINT32_VAL(AUTOPLAY_DELAY);
1167 vsst->header_interval.tv_sec = 5; /* should this be configurable? */
1168 vsst->afs_socket = afs_socket;
1169 ms2tv(announce_time, &vsst->announce_tv);
1170 PARA_INFO_LOG("announce timeval: %lums\n", tv2ms(&vsst->announce_tv));
1171 INIT_LIST_HEAD(&fec_client_list);
1172 FOR_EACH_SENDER(i) {
1173 PARA_NOTICE_LOG("initializing %s sender\n", senders[i]->name);
1176 mmd->sender_cmd_data.cmd_num = -1;
1177 if (OPT_GIVEN(AUTOPLAY)) {
1179 mmd->vss_status_flags |= VSS_PLAYING;
1180 mmd->new_vss_status_flags |= VSS_PLAYING;
1181 ms2tv(autoplay_delay, &tmp);
1182 tv_add(clock_get_realtime(NULL), &tmp, &vsst->autoplay_barrier);
1183 tv_add(&vsst->autoplay_barrier, &vsst->announce_tv,
1184 &vsst->data_send_barrier);
1186 vsst->task = task_register(&(struct task_info) {
1188 .pre_select = vss_pre_select,
1189 .post_select = vss_post_select,
1195 * Turn off the virtual streaming system.
1197 * This is only executed on exit. It calls the ->shutdowwn method of all senders.
1199 void vss_shutdown(void)
1203 FOR_EACH_SENDER(i) {
1204 if (!senders[i]->shutdown)
1206 PARA_NOTICE_LOG("shutting down %s sender\n", senders[i]->name);
1207 senders[i]->shutdown();