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
;
132 /** Number of bytes per slice for this group. */
133 uint16_t slice_bytes
;
136 enum fec_client_state
{
137 FEC_STATE_NONE
= 0, /**< not initialized and not enabled */
138 FEC_STATE_DISABLED
, /**< temporarily disabled */
139 FEC_STATE_READY_TO_RUN
/**< initialized and enabled */
143 * Describes one connected FEC client.
146 /** Current state of the client */
147 enum fec_client_state state
;
148 /** The connected sender client (transport layer). */
149 struct sender_client
*sc
;
150 /** Parameters requested by the client. */
151 struct fec_client_parms
*fcp
;
152 /** Used by the core FEC code. */
153 struct fec_parms
*parms
;
154 /** The position of this client in the fec client list. */
155 struct list_head node
;
156 /** When the first slice for this client was sent. */
157 struct timeval stream_start
;
158 /** The first chunk sent to this FEC client. */
159 int first_stream_chunk
;
160 /** Describes the current group. */
161 struct fec_group group
;
162 /** The current slice. */
163 uint8_t current_slice_num
;
164 /** The data to be FEC-encoded (point to a region within the mapped audio file). */
165 const unsigned char **src_data
;
166 /** Last time an audio header was sent. */
167 struct timeval next_header_time
;
168 /** Used for the last source pointer of an audio file. */
169 unsigned char *extra_src_buf
;
170 /** Extra slices needed to store largest chunk + header. */
171 int num_extra_slices
;
172 /** Contains the FEC-encoded data. */
173 unsigned char *enc_buf
;
174 /** Maximal packet size. */
179 * Get the chunk time of the current audio file.
181 * \return A pointer to a struct containing the chunk time, or NULL,
182 * if currently no audio file is selected.
184 struct timeval
*vss_chunk_time(void)
186 if (mmd
->afd
.afhi
.chunk_tv
.tv_sec
== 0 &&
187 mmd
->afd
.afhi
.chunk_tv
.tv_usec
== 0)
189 return &mmd
->afd
.afhi
.chunk_tv
;
193 * Write a fec header to a buffer.
195 * \param buf The buffer to write to.
196 * \param h The fec header to write.
198 static void write_fec_header(struct fec_client
*fc
, struct vss_task
*vsst
)
200 char *buf
= (char *)fc
->enc_buf
;
201 struct fec_group
*g
= &fc
->group
;
202 struct fec_client_parms
*p
= fc
->fcp
;
204 write_u32(buf
, FEC_MAGIC
);
206 write_u8(buf
+ 4, p
->slices_per_group
+ fc
->num_extra_slices
);
207 write_u8(buf
+ 5, p
->data_slices_per_group
+ fc
->num_extra_slices
);
208 write_u32(buf
+ 6, g
->num_header_slices
? vsst
->header_len
: 0);
210 write_u32(buf
+ 10, g
->num
);
211 write_u32(buf
+ 14, g
->bytes
);
213 write_u8(buf
+ 18, fc
->current_slice_num
);
214 write_u16(buf
+ 20, g
->slice_bytes
);
215 write_u8(buf
+ 22, g
->first_chunk
? 0 : 1);
216 write_u8(buf
+ 23, vsst
->header_len
? 1 : 0);
217 memset(buf
+ 24, 0, 7);
220 static bool need_audio_header(struct fec_client
*fc
, struct vss_task
*vsst
)
222 if (!mmd
->current_chunk
) {
223 tv_add(now
, &vsst
->header_interval
, &fc
->next_header_time
);
226 if (!vsst
->header_buf
)
228 if (vsst
->header_len
== 0)
230 if (fc
->group
.num
&& tv_diff(&fc
->next_header_time
, now
, NULL
) > 0)
232 tv_add(now
, &vsst
->header_interval
, &fc
->next_header_time
);
236 static int num_slices(long unsigned bytes
, int max_payload
, int rs
)
240 assert(max_payload
> 0);
242 ret
= DIV_ROUND_UP(bytes
, max_payload
);
248 /* set group start and group duration */
249 static void set_group_timing(struct fec_client
*fc
, struct fec_group
*g
)
251 struct timeval
*chunk_tv
= vss_chunk_time();
253 tv_scale(g
->num_chunks
, chunk_tv
, &g
->duration
);
254 tv_divide(fc
->fcp
->slices_per_group
+ fc
->num_extra_slices
,
255 &g
->duration
, &g
->slice_duration
);
256 PARA_DEBUG_LOG("durations (group/chunk/slice): %lu/%lu/%lu\n",
257 tv2ms(&g
->duration
), tv2ms(chunk_tv
), tv2ms(&g
->slice_duration
));
260 static int initialize_fec_client(struct fec_client
*fc
, struct vss_task
*vsst
)
263 int hs
, ds
, rs
; /* header/data/redundant slices */
264 struct fec_client_parms
*fcp
= fc
->fcp
;
269 * Set the maximum slice size to the Maximum Packet Size if the
270 * transport protocol allows to determine this value. The user
271 * can specify a slice size up to this value.
273 ret
= fcp
->init_fec(fc
->sc
);
278 fc
->mps
= generic_max_transport_msg_size(fc
->sc
->fd
);
279 if (fc
->mps
<= FEC_HEADER_SIZE
)
280 return -ERRNO_TO_PARA_ERROR(EINVAL
);
282 rs
= fc
->fcp
->slices_per_group
- fc
->fcp
->data_slices_per_group
;
283 ret
= num_slices(vsst
->header_len
, fc
->mps
- FEC_HEADER_SIZE
, rs
);
287 ret
= num_slices(mmd
->afd
.max_chunk_size
, fc
->mps
- FEC_HEADER_SIZE
, rs
);
292 if (k
< fc
->fcp
->data_slices_per_group
)
293 k
= fc
->fcp
->data_slices_per_group
;
294 fc
->num_extra_slices
= k
- fc
->fcp
->data_slices_per_group
;
297 ret
= fec_new(k
, n
, &fc
->parms
);
300 PARA_INFO_LOG("mps: %d, k: %d, n: %d, extra slices: %d\n",
301 fc
->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
, fc
->mps
);
304 fc
->extra_src_buf
= para_realloc(fc
->extra_src_buf
, fc
->mps
);
306 fc
->state
= FEC_STATE_READY_TO_RUN
;
307 fc
->next_header_time
.tv_sec
= 0;
308 fc
->stream_start
= *now
;
309 fc
->first_stream_chunk
= mmd
->current_chunk
;
316 static void compute_group_size(struct vss_task
*vsst
, struct fec_group
*g
,
319 int i
, max_chunks
= PARA_MAX(1LU, 150 / tv2ms(vss_chunk_time()));
324 * Include chunks into the group until the group duration is at least
325 * 150ms. For ogg and wma, a single chunk's duration (ogg page/wma
326 * super frame) is already larger than 150ms, so a FEC group consists
327 * of exactly one chunk for these audio formats.
332 int chunk_num
= g
->first_chunk
+ i
;
334 if (g
->bytes
> 0 && i
>= max_chunks
) /* duration limit */
336 if (chunk_num
>= mmd
->afd
.afhi
.chunks_total
) /* eof */
338 afh_get_chunk(chunk_num
, &mmd
->afd
.afhi
, vsst
->map
, &buf
, &len
);
339 if (g
->bytes
+ len
> max_bytes
)
341 /* Include this chunk */
345 assert(g
->num_chunks
);
349 * Compute the slice size of the next group.
351 * The FEC parameters n and k are fixed but the slice size varies per
352 * FEC group. We'd like to choose slices as small as possible to avoid
353 * unnecessary FEC calculations but large enough to guarantee that the
354 * k data slices suffice to encode the header (if needed) and the data
357 * Once we know the payload of the next group, we define the number s
358 * of bytes per slice for this group by
360 * s = ceil(payload / k)
362 * However, for header streams, computing s is more complicated since no
363 * overlapping of header and data slices is possible. Hence we have k >=
364 * 2 and s must satisfy
366 * (*) ceil(h / s) + ceil(d / s) <= k
368 * where h and d are payload of the header and the data chunk(s)
369 * respectively. In general there is no value for s such that (*)
370 * becomes an equality, for example if h = 4000, d = 5000 and k = 10.
372 * We use the following approach for computing a suitable value for s:
375 * k1 := ceil(k * min(h, d) / (h + d)),
378 * Note that k >= 2 implies k1 > 0 and k2 > 0, so
380 * s := max(ceil(min(h, d) / k1), ceil(max(h, d) / k2))
382 * is well-defined. Inequality (*) holds for this value of s since k1
383 * slices suffice to store min(h, d) while k2 slices suffice to store
384 * max(h, d), i.e. the first addent of (*) is bounded by k1 and the
387 * For the above example we obtain
389 * k1 = ceil(10 * 4000 / 9000) = 5, k2 = 5,
390 * s = max(4000 / 5, 5000 / 5) = 1000,
392 * which is optimal since a slice size of 999 bytes would already require
395 static int compute_slice_size(struct fec_client
*fc
, struct vss_task
*vsst
)
397 struct fec_group
*g
= &fc
->group
;
398 int k
= fc
->fcp
->data_slices_per_group
+ fc
->num_extra_slices
;
399 int n
= fc
->fcp
->slices_per_group
+ fc
->num_extra_slices
;
400 int ret
, k1
, k2
, h
, d
, min
, max
, sum
;
401 int max_slice_bytes
= fc
->mps
- FEC_HEADER_SIZE
;
404 if (!need_audio_header(fc
, vsst
)) {
405 max_group_bytes
= k
* max_slice_bytes
;
406 g
->num_header_slices
= 0;
407 compute_group_size(vsst
, g
, max_group_bytes
);
408 g
->slice_bytes
= DIV_ROUND_UP(g
->bytes
, k
);
409 if (g
->slice_bytes
== 0)
413 h
= vsst
->header_len
;
414 max_group_bytes
= (k
- num_slices(h
, max_slice_bytes
, n
- k
))
416 compute_group_size(vsst
, g
, max_group_bytes
);
419 g
->slice_bytes
= DIV_ROUND_UP(h
, k
);
420 ret
= num_slices(vsst
->header_len
, g
->slice_bytes
, n
- k
);
423 g
->num_header_slices
= ret
;
426 min
= PARA_MIN(h
, d
);
427 max
= PARA_MAX(h
, d
);
429 k1
= DIV_ROUND_UP(k
* min
, sum
);
434 g
->slice_bytes
= PARA_MAX(DIV_ROUND_UP(min
, k1
), DIV_ROUND_UP(max
, k2
));
436 * This value of s := g->slice_bytes satisfies inequality (*) above,
437 * but it might be larger than max_slice_bytes. However, we know that
438 * max_slice_bytes are sufficient to store header and data, so:
440 g
->slice_bytes
= PARA_MIN((int)g
->slice_bytes
, max_slice_bytes
);
442 ret
= num_slices(vsst
->header_len
, g
->slice_bytes
, n
- k
);
445 g
->num_header_slices
= ret
;
449 static int setup_next_fec_group(struct fec_client
*fc
, struct vss_task
*vsst
)
451 int ret
, i
, k
, n
, data_slices
;
454 struct fec_group
*g
= &fc
->group
;
456 if (fc
->state
== FEC_STATE_NONE
) {
457 ret
= initialize_fec_client(fc
, vsst
);
460 g
->first_chunk
= mmd
->current_chunk
;
465 if (g
->first_chunk
+ g
->num_chunks
>= mmd
->afd
.afhi
.chunks_total
)
468 * Start and duration of this group depend only on the previous
469 * group. Compute the new group start as g->start += g->duration.
472 tv_add(&tmp
, &g
->duration
, &g
->start
);
473 set_group_timing(fc
, g
);
474 g
->first_chunk
+= g
->num_chunks
;
477 k
= fc
->fcp
->data_slices_per_group
+ fc
->num_extra_slices
;
478 n
= fc
->fcp
->slices_per_group
+ fc
->num_extra_slices
;
480 compute_slice_size(fc
, vsst
);
481 assert(g
->slice_bytes
> 0);
482 ret
= num_slices(g
->bytes
, g
->slice_bytes
, n
- k
);
486 assert(g
->num_header_slices
+ data_slices
<= k
);
487 fc
->current_slice_num
= 0;
489 set_group_timing(fc
, g
);
491 /* setup header slices */
492 buf
= vsst
->header_buf
;
493 for (i
= 0; i
< g
->num_header_slices
; i
++) {
494 fc
->src_data
[i
] = (const unsigned char *)buf
;
495 buf
+= g
->slice_bytes
;
498 /* setup data slices */
499 afh_get_chunk(g
->first_chunk
, &mmd
->afd
.afhi
, vsst
->map
, &buf
, &len
);
500 for (; i
< g
->num_header_slices
+ data_slices
; i
++) {
501 if (buf
+ g
->slice_bytes
> vsst
->map
+ mmd
->size
) {
503 * Can not use the memory mapped audio file for this
504 * slice as it goes beyond the map. This slice will not
507 uint32_t payload_size
= vsst
->map
+ mmd
->size
- buf
;
508 memcpy(fc
->extra_src_buf
, buf
, payload_size
);
509 if (payload_size
< g
->slice_bytes
)
510 memset(fc
->extra_src_buf
+ payload_size
, 0,
511 g
->slice_bytes
- payload_size
);
512 fc
->src_data
[i
] = fc
->extra_src_buf
;
516 fc
->src_data
[i
] = (const unsigned char *)buf
;
517 buf
+= g
->slice_bytes
;
520 /* use arbitrary data for all remaining slices */
523 fc
->src_data
[i
] = (const unsigned char *)buf
;
525 PARA_DEBUG_LOG("FEC group %d: %d chunks (%d - %d), %d bytes\n",
526 g
->num
, g
->num_chunks
, g
->first_chunk
,
527 g
->first_chunk
+ g
->num_chunks
- 1, g
->bytes
529 PARA_DEBUG_LOG("slice_bytes: %d, %d header slices, %d data slices\n",
530 g
->slice_bytes
, g
->num_header_slices
, data_slices
535 static int compute_next_fec_slice(struct fec_client
*fc
, struct vss_task
*vsst
)
537 if (fc
->state
== FEC_STATE_NONE
|| fc
->current_slice_num
538 == fc
->fcp
->slices_per_group
+ fc
->num_extra_slices
) {
539 int ret
= setup_next_fec_group(fc
, vsst
);
543 PARA_ERROR_LOG("%s\n", para_strerror(-ret
));
544 PARA_ERROR_LOG("FEC client temporarily disabled\n");
545 fc
->state
= FEC_STATE_DISABLED
;
549 write_fec_header(fc
, vsst
);
550 fec_encode(fc
->parms
, fc
->src_data
, fc
->enc_buf
+ FEC_HEADER_SIZE
,
551 fc
->current_slice_num
, fc
->group
.slice_bytes
);
556 * Return a buffer that marks the end of the stream.
558 * \param buf Result pointer.
559 * \return The length of the eof buffer.
561 * This is used for (multicast) udp streaming where closing the socket on the
562 * sender might not give rise to an eof condition at the peer.
564 size_t vss_get_fec_eof_packet(const char **buf
)
566 static const char fec_eof_packet
[FEC_HEADER_SIZE
] = FEC_EOF_PACKET
;
567 *buf
= fec_eof_packet
;
568 return FEC_HEADER_SIZE
;
572 * Add one entry to the list of active fec clients.
574 * \param sc Generic sender_client data of the transport layer.
575 * \param fcp FEC parameters as supplied by the transport layer.
577 * \return Newly allocated fec_client struct.
579 struct fec_client
*vss_add_fec_client(struct sender_client
*sc
,
580 struct fec_client_parms
*fcp
)
582 struct fec_client
*fc
= para_calloc(sizeof(*fc
));
586 para_list_add(&fc
->node
, &fec_client_list
);
591 * Remove one entry from the list of active fec clients.
593 * \param fc The client to be removed.
595 void vss_del_fec_client(struct fec_client
*fc
)
600 free(fc
->extra_src_buf
);
606 * Compute if/when next slice is due. If it isn't due yet and \a diff is
607 * not \p Null, compute the time difference next - now, where
609 * next = stream_start + (first_group_chunk - first_stream_chunk)
610 * * chunk_time + slice_num * slice_time
612 static int next_slice_is_due(struct fec_client
*fc
, struct timeval
*diff
)
614 struct timeval tmp
, next
;
617 if (fc
->state
== FEC_STATE_NONE
)
619 tv_scale(fc
->current_slice_num
, &fc
->group
.slice_duration
, &tmp
);
620 tv_add(&tmp
, &fc
->group
.start
, &next
);
621 ret
= tv_diff(&next
, now
, diff
);
622 return ret
< 0? 1 : 0;
625 static void compute_slice_timeout(struct timeval
*timeout
)
627 struct fec_client
*fc
;
629 list_for_each_entry(fc
, &fec_client_list
, node
) {
632 if (fc
->state
!= FEC_STATE_READY_TO_RUN
)
634 if (next_slice_is_due(fc
, &diff
)) {
636 timeout
->tv_usec
= 0;
639 /* timeout = min(timeout, diff) */
640 if (tv_diff(&diff
, timeout
, NULL
) < 0)
645 static void set_eof_barrier(struct vss_task
*vsst
)
647 struct fec_client
*fc
;
648 struct timeval timeout
= {1, 0}, *chunk_tv
= vss_chunk_time();
652 list_for_each_entry(fc
, &fec_client_list
, node
) {
653 struct timeval group_duration
;
655 if (fc
->state
!= FEC_STATE_READY_TO_RUN
)
657 tv_scale(fc
->group
.num_chunks
, chunk_tv
, &group_duration
);
658 if (tv_diff(&timeout
, &group_duration
, NULL
) < 0)
659 timeout
= group_duration
;
662 tv_add(now
, &timeout
, &vsst
->eof_barrier
);
666 * Check if vss status flag \a P (playing) is set.
668 * \return Greater than zero if playing, zero otherwise.
671 unsigned int vss_playing(void)
673 return mmd
->new_vss_status_flags
& VSS_PLAYING
;
677 * Check if the \a N (next) status flag is set.
679 * \return Greater than zero if set, zero if not.
682 unsigned int vss_next(void)
684 return mmd
->new_vss_status_flags
& VSS_NEXT
;
688 * Check if a reposition request is pending.
690 * \return Greater than zero if true, zero otherwise.
693 unsigned int vss_repos(void)
695 return mmd
->new_vss_status_flags
& VSS_REPOS
;
699 * Check if the vss is currently paused.
701 * \return Greater than zero if paused, zero otherwise.
704 unsigned int vss_paused(void)
706 return !(mmd
->new_vss_status_flags
& VSS_NEXT
)
707 && !(mmd
->new_vss_status_flags
& VSS_PLAYING
);
711 * Check if the vss is currently stopped.
713 * \return Greater than zero if paused, zero otherwise.
716 unsigned int vss_stopped(void)
718 return (mmd
->new_vss_status_flags
& VSS_NEXT
)
719 && !(mmd
->new_vss_status_flags
& VSS_PLAYING
);
722 static int chk_barrier(const char *bname
, const struct timeval
*barrier
,
723 struct timeval
*diff
, int print_log
)
727 if (tv_diff(now
, barrier
, diff
) > 0)
731 PARA_DEBUG_LOG("%s barrier: %lims left\n", bname
, ms
);
736 * != NULL: timeout for next chunk
737 * NULL: nothing to do
739 static struct timeval
*vss_compute_timeout(struct vss_task
*vsst
)
741 static struct timeval the_timeout
;
742 struct timeval next_chunk
;
744 if (vss_next() && vsst
->map
) {
745 /* only sleep a bit, nec*/
746 the_timeout
.tv_sec
= 0;
747 the_timeout
.tv_usec
= 100;
750 if (chk_barrier("autoplay_delay", &vsst
->autoplay_barrier
,
751 &the_timeout
, 1) < 0)
753 if (chk_barrier("eof", &vsst
->eof_barrier
, &the_timeout
, 1) < 0)
755 if (chk_barrier("data send", &vsst
->data_send_barrier
,
756 &the_timeout
, 1) < 0)
758 if (!vss_playing() || !vsst
->map
)
760 compute_chunk_time(mmd
->chunks_sent
, &mmd
->afd
.afhi
.chunk_tv
,
761 &mmd
->stream_start
, &next_chunk
);
762 if (chk_barrier("chunk", &next_chunk
, &the_timeout
, 0) >= 0) {
763 /* chunk is due or bof */
764 the_timeout
.tv_sec
= 0;
765 the_timeout
.tv_usec
= 0;
768 /* compute min of current timeout and next slice time */
769 compute_slice_timeout(&the_timeout
);
773 static void vss_eof(struct vss_task
*vsst
)
778 if (mmd
->new_vss_status_flags
& VSS_NOMORE
)
779 mmd
->new_vss_status_flags
= VSS_NEXT
;
780 set_eof_barrier(vsst
);
781 para_munmap(vsst
->map
, mmd
->size
);
783 mmd
->chunks_sent
= 0;
785 mmd
->afd
.afhi
.seconds_total
= 0;
786 mmd
->afd
.afhi
.chunk_tv
.tv_sec
= 0;
787 mmd
->afd
.afhi
.chunk_tv
.tv_usec
= 0;
788 free(mmd
->afd
.afhi
.chunk_table
);
789 mmd
->afd
.afhi
.chunk_table
= NULL
;
795 static int need_to_request_new_audio_file(struct vss_task
*vsst
)
799 if (vsst
->map
) /* have audio file */
801 if (!vss_playing()) /* don't need one */
803 if (mmd
->new_vss_status_flags
& VSS_NOMORE
)
805 if (vsst
->afsss
== AFS_SOCKET_AFD_PENDING
) /* already requested one */
807 if (chk_barrier("autoplay_delay", &vsst
->autoplay_barrier
,
813 static void set_mmd_offset(void)
815 struct timeval offset
;
816 tv_scale(mmd
->current_chunk
, &mmd
->afd
.afhi
.chunk_tv
, &offset
);
817 mmd
->offset
= tv2ms(&offset
);
821 * Compute the timeout for the main select-loop of the scheduler.
823 * \param s Pointer to the server scheduler.
824 * \param t Pointer to the vss task structure.
826 * Before the timeout is computed, the current vss status flags are evaluated
827 * and acted upon by calling appropriate functions from the lower layers.
828 * Possible actions include
830 * - request a new audio file from afs,
831 * - shutdown of all senders (stop/pause command),
832 * - reposition the stream (ff/jmp command).
834 static void vss_pre_select(struct sched
*s
, struct task
*t
)
838 struct vss_task
*vsst
= container_of(t
, struct vss_task
, task
);
840 if (!vsst
->map
|| vss_next() || vss_paused() || vss_repos()) {
841 struct fec_client
*fc
, *tmp
;
842 for (i
= 0; senders
[i
].name
; i
++)
843 if (senders
[i
].shutdown_clients
)
844 senders
[i
].shutdown_clients();
845 list_for_each_entry_safe(fc
, tmp
, &fec_client_list
, node
)
846 fc
->state
= FEC_STATE_NONE
;
847 mmd
->stream_start
.tv_sec
= 0;
848 mmd
->stream_start
.tv_usec
= 0;
852 else if (vss_paused()) {
853 if (mmd
->chunks_sent
)
854 set_eof_barrier(vsst
);
855 mmd
->chunks_sent
= 0;
856 } else if (vss_repos()) {
857 tv_add(now
, &vsst
->announce_tv
, &vsst
->data_send_barrier
);
858 set_eof_barrier(vsst
);
859 mmd
->chunks_sent
= 0;
860 mmd
->current_chunk
= mmd
->repos_request
;
861 mmd
->new_vss_status_flags
&= ~VSS_REPOS
;
864 if (need_to_request_new_audio_file(vsst
)) {
865 PARA_DEBUG_LOG("ready and playing, but no audio file\n");
866 para_fd_set(vsst
->afs_socket
, &s
->wfds
, &s
->max_fileno
);
867 vsst
->afsss
= AFS_SOCKET_CHECK_FOR_WRITE
;
869 para_fd_set(vsst
->afs_socket
, &s
->rfds
, &s
->max_fileno
);
870 for (i
= 0; senders
[i
].name
; i
++) {
871 if (!senders
[i
].pre_select
)
873 senders
[i
].pre_select(&s
->max_fileno
, &s
->rfds
, &s
->wfds
);
875 tv
= vss_compute_timeout(vsst
);
877 sched_request_timeout(tv
, s
);
880 static int recv_afs_msg(int afs_socket
, int *fd
, uint32_t *code
, uint32_t *data
)
882 char control
[255], buf
[8];
883 struct msghdr msg
= {.msg_iov
= NULL
};
884 struct cmsghdr
*cmsg
;
890 iov
.iov_len
= sizeof(buf
);
893 msg
.msg_control
= control
;
894 msg
.msg_controllen
= sizeof(control
);
895 memset(buf
, 0, sizeof(buf
));
896 ret
= recvmsg(afs_socket
, &msg
, 0);
898 return -ERRNO_TO_PARA_ERROR(errno
);
899 if (iov
.iov_len
!= sizeof(buf
))
900 return -E_AFS_SHORT_READ
;
901 *code
= *(uint32_t*)buf
;
902 *data
= *(uint32_t*)(buf
+ 4);
903 for (cmsg
= CMSG_FIRSTHDR(&msg
); cmsg
; cmsg
= CMSG_NXTHDR(&msg
, cmsg
)) {
904 if (cmsg
->cmsg_level
!= SOL_SOCKET
905 || cmsg
->cmsg_type
!= SCM_RIGHTS
)
907 if ((cmsg
->cmsg_len
- CMSG_LEN(0)) / sizeof(int) != 1)
909 *fd
= *(int *)CMSG_DATA(cmsg
);
914 static void recv_afs_result(struct vss_task
*vsst
, fd_set
*rfds
)
916 int ret
, passed_fd
, shmid
;
917 uint32_t afs_code
= 0, afs_data
= 0;
920 if (!FD_ISSET(vsst
->afs_socket
, rfds
))
922 ret
= recv_afs_msg(vsst
->afs_socket
, &passed_fd
, &afs_code
, &afs_data
);
923 if (ret
== -ERRNO_TO_PARA_ERROR(EAGAIN
))
927 vsst
->afsss
= AFS_SOCKET_READY
;
928 PARA_DEBUG_LOG("fd: %d, code: %u, shmid: %u\n", passed_fd
, afs_code
,
931 if (afs_code
!= NEXT_AUDIO_FILE
)
936 ret
= load_afd(shmid
, &mmd
->afd
);
940 ret
= fstat(passed_fd
, &statbuf
);
942 PARA_ERROR_LOG("fstat error:\n");
943 ret
= -ERRNO_TO_PARA_ERROR(errno
);
946 mmd
->size
= statbuf
.st_size
;
947 mmd
->mtime
= statbuf
.st_mtime
;
948 ret
= para_mmap(mmd
->size
, PROT_READ
, MAP_PRIVATE
, passed_fd
,
953 mmd
->chunks_sent
= 0;
954 mmd
->current_chunk
= 0;
958 mmd
->new_vss_status_flags
&= (~VSS_NEXT
);
959 afh_get_header(&mmd
->afd
.afhi
, vsst
->map
, &vsst
->header_buf
,
963 free(mmd
->afd
.afhi
.chunk_table
);
966 PARA_ERROR_LOG("%s\n", para_strerror(-ret
));
967 mmd
->new_vss_status_flags
= VSS_NEXT
;
971 * Main sending function.
973 * This function gets called from vss_post_select(). It checks whether the next
974 * chunk of data should be pushed out. It obtains a pointer to the data to be
975 * sent out as well as its length from mmd->afd.afhi. This information is then
976 * passed to each supported sender's send() function as well as to the send()
977 * functions of each registered fec client.
979 static void vss_send(struct vss_task
*vsst
)
981 int i
, fec_active
= 0;
983 struct fec_client
*fc
, *tmp_fc
;
985 if (!vsst
->map
|| !vss_playing())
987 if (chk_barrier("eof", &vsst
->eof_barrier
, &due
, 1) < 0)
989 if (chk_barrier("data send", &vsst
->data_send_barrier
,
992 list_for_each_entry_safe(fc
, tmp_fc
, &fec_client_list
, node
) {
993 if (fc
->state
== FEC_STATE_DISABLED
)
995 if (!next_slice_is_due(fc
, NULL
)) {
999 if (compute_next_fec_slice(fc
, vsst
) <= 0)
1001 PARA_DEBUG_LOG("sending %d:%d (%u bytes)\n", fc
->group
.num
,
1002 fc
->current_slice_num
, fc
->group
.slice_bytes
);
1003 fc
->fcp
->send_fec(fc
->sc
, (char *)fc
->enc_buf
,
1004 fc
->group
.slice_bytes
+ FEC_HEADER_SIZE
);
1005 fc
->current_slice_num
++;
1008 if (mmd
->current_chunk
>= mmd
->afd
.afhi
.chunks_total
) { /* eof */
1010 mmd
->new_vss_status_flags
|= VSS_NEXT
;
1013 compute_chunk_time(mmd
->chunks_sent
, &mmd
->afd
.afhi
.chunk_tv
,
1014 &mmd
->stream_start
, &due
);
1015 if (tv_diff(&due
, now
, NULL
) <= 0) {
1019 if (!mmd
->chunks_sent
) {
1020 mmd
->stream_start
= *now
;
1025 * We call the send function also in case of empty chunks as
1026 * they might have still some data queued which can be sent in
1029 afh_get_chunk(mmd
->current_chunk
, &mmd
->afd
.afhi
, vsst
->map
,
1031 for (i
= 0; senders
[i
].name
; i
++) {
1032 if (!senders
[i
].send
)
1034 senders
[i
].send(mmd
->current_chunk
, mmd
->chunks_sent
,
1035 buf
, len
, vsst
->header_buf
, vsst
->header_len
);
1038 mmd
->current_chunk
++;
1042 static void vss_post_select(struct sched
*s
, struct task
*t
)
1045 struct vss_task
*vsst
= container_of(t
, struct vss_task
, task
);
1048 if (mmd
->sender_cmd_data
.cmd_num
>= 0) {
1049 int num
= mmd
->sender_cmd_data
.cmd_num
,
1050 sender_num
= mmd
->sender_cmd_data
.sender_num
;
1052 if (senders
[sender_num
].client_cmds
[num
]) {
1053 ret
= senders
[sender_num
].client_cmds
[num
]
1054 (&mmd
->sender_cmd_data
);
1056 PARA_ERROR_LOG("%s\n", para_strerror(-ret
));
1058 mmd
->sender_cmd_data
.cmd_num
= -1;
1060 if (vsst
->afsss
!= AFS_SOCKET_CHECK_FOR_WRITE
)
1061 recv_afs_result(vsst
, &s
->rfds
);
1062 else if (FD_ISSET(vsst
->afs_socket
, &s
->wfds
)) {
1063 PARA_NOTICE_LOG("requesting new fd from afs\n");
1064 ret
= send_buffer(vsst
->afs_socket
, "new");
1066 PARA_CRIT_LOG("%s\n", para_strerror(-ret
));
1068 vsst
->afsss
= AFS_SOCKET_AFD_PENDING
;
1070 for (i
= 0; senders
[i
].name
; i
++) {
1071 if (!senders
[i
].post_select
)
1073 senders
[i
].post_select(&s
->rfds
, &s
->wfds
);
1075 if ((vss_playing() && !(mmd
->vss_status_flags
& VSS_PLAYING
)) ||
1076 (vss_next() && vss_playing()))
1077 tv_add(now
, &vsst
->announce_tv
, &vsst
->data_send_barrier
);
1082 * Initialize the virtual streaming system task.
1084 * \param afs_socket The fd for communication with afs.
1086 * This also initializes all supported senders and starts streaming
1087 * if the --autoplay command line flag was given.
1089 void init_vss_task(int afs_socket
)
1091 static struct vss_task vss_task_struct
, *vsst
= &vss_task_struct
;
1093 char *hn
= para_hostname(), *home
= para_homedir();
1094 long unsigned announce_time
= conf
.announce_time_arg
> 0?
1095 conf
.announce_time_arg
: 300,
1096 autoplay_delay
= conf
.autoplay_delay_arg
> 0?
1097 conf
.autoplay_delay_arg
: 0;
1098 vsst
->header_interval
.tv_sec
= 5; /* should this be configurable? */
1099 vsst
->afs_socket
= afs_socket
;
1100 vsst
->task
.pre_select
= vss_pre_select
;
1101 vsst
->task
.post_select
= vss_post_select
;
1102 ms2tv(announce_time
, &vsst
->announce_tv
);
1103 PARA_INFO_LOG("announce timeval: %lums\n", tv2ms(&vsst
->announce_tv
));
1104 INIT_LIST_HEAD(&fec_client_list
);
1105 for (i
= 0; senders
[i
].name
; i
++) {
1106 PARA_NOTICE_LOG("initializing %s sender\n", senders
[i
].name
);
1107 senders
[i
].init(&senders
[i
]);
1111 mmd
->sender_cmd_data
.cmd_num
= -1;
1112 if (conf
.autoplay_given
) {
1114 mmd
->vss_status_flags
|= VSS_PLAYING
;
1115 mmd
->new_vss_status_flags
|= VSS_PLAYING
;
1116 ms2tv(autoplay_delay
, &tmp
);
1117 tv_add(now
, &tmp
, &vsst
->autoplay_barrier
);
1118 tv_add(&vsst
->autoplay_barrier
, &vsst
->announce_tv
,
1119 &vsst
->data_send_barrier
);
1121 register_task(&vsst
->task
);