vss: add state variable for fec client
[paraslash.git] / vss.c
1 /*
2 * Copyright (C) 1997-2010 Andre Noll <maan@systemlinux.org>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /** \file vss.c The virtual streaming system.
8 *
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
11 * senders.
12 */
13
14 #include <regex.h>
15 #include <dirent.h>
16 #include <osl.h>
17
18 #include "para.h"
19 #include "error.h"
20 #include "portable_io.h"
21 #include "fec.h"
22 #include "string.h"
23 #include "afh.h"
24 #include "afs.h"
25 #include "server.h"
26 #include "net.h"
27 #include "server.cmdline.h"
28 #include "list.h"
29 #include "send.h"
30 #include "vss.h"
31 #include "ipc.h"
32 #include "fd.h"
33 #include "sched.h"
34
35 extern struct misc_meta_data *mmd;
36
37 extern void dccp_send_init(struct sender *);
38 extern void http_send_init(struct sender *);
39 extern void udp_send_init(struct sender *);
40
41 /** The list of supported senders. */
42 struct sender senders[] = {
43 {
44 .name = "http",
45 .init = http_send_init,
46 },
47 {
48 .name = "dccp",
49 .init = dccp_send_init,
50 },
51 {
52 .name = "udp",
53 .init = udp_send_init,
54 },
55 {
56 .name = NULL,
57 }
58 };
59
60 /** The possible states of the afs socket. */
61 enum afs_socket_status {
62 /** Socket is inactive. */
63 AFS_SOCKET_READY,
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
68 };
69
70 /** The task structure for the virtual streaming system. */
71 struct vss_task {
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. */
81 int afs_socket;
82 /** The current state of \a afs_socket. */
83 enum afs_socket_status afsss;
84 /** The memory mapped audio file. */
85 char *map;
86 /** Used by the scheduler. */
87 struct task task;
88 /** Pointer to the header of the mapped audio file. */
89 const char *header_buf;
90 /** Length of the audio file header. */
91 size_t header_len;
92 /** Time between audio file headers are sent. */
93 struct timeval header_interval;
94 };
95
96 /**
97 * The list of currently connected fec clients.
98 *
99 * Senders may use \ref vss_add_fec_client() to add entries to the list.
100 */
101 static struct list_head fec_client_list;
102
103 /**
104 * Data associated with one FEC group.
105 *
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.
109 *
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.
114 */
115 struct fec_group {
116 /** The number of the FEC group. */
117 uint32_t num;
118 /** Number of bytes in this group. */
119 uint32_t bytes;
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. */
123 uint32_t num_chunks;
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 };
133
134 enum fec_client_state {
135 FEC_STATE_NONE = 0, /**< not initialized and not enabled */
136 FEC_STATE_DISABLED, /**< temporarily disabled */
137 FEC_STATE_READY_TO_RUN /**< initialized and enabled */
138 };
139
140 /**
141 * Describes one connected FEC client.
142 */
143 struct fec_client {
144 /** Current state of the client */
145 enum fec_client_state state;
146 /** The connected sender client (transport layer). */
147 struct sender_client *sc;
148 /** Parameters requested by the client. */
149 struct fec_client_parms *fcp;
150 /** Used by the core FEC code. */
151 struct fec_parms *parms;
152 /** The position of this client in the fec client list. */
153 struct list_head node;
154 /** When the first slice for this client was sent. */
155 struct timeval stream_start;
156 /** The first chunk sent to this FEC client. */
157 int first_stream_chunk;
158 /** Describes the current group. */
159 struct fec_group group;
160 /** The current slice. */
161 uint8_t current_slice_num;
162 /** The data to be FEC-encoded (point to a region within the mapped audio file). */
163 const unsigned char **src_data;
164 /** Last time an audio header was sent. */
165 struct timeval next_header_time;
166 /** Used for the last source pointer of an audio file. */
167 unsigned char *extra_src_buf;
168 /** Extra slices needed to store largest chunk + header. */
169 int num_extra_slices;
170 /** Contains the FEC-encoded data. */
171 unsigned char *enc_buf;
172 /** Pointer obtained from sender when the client is added. */
173 void *private_data;
174 };
175
176 /**
177 * Get the chunk time of the current audio file.
178 *
179 * \return A pointer to a struct containing the chunk time, or NULL,
180 * if currently no audio file is selected.
181 */
182 struct timeval *vss_chunk_time(void)
183 {
184 if (mmd->afd.afhi.chunk_tv.tv_sec == 0 &&
185 mmd->afd.afhi.chunk_tv.tv_usec == 0)
186 return NULL;
187 return &mmd->afd.afhi.chunk_tv;
188 }
189
190 /**
191 * Write a fec header to a buffer.
192 *
193 * \param buf The buffer to write to.
194 * \param h The fec header to write.
195 */
196 static void write_fec_header(struct fec_client *fc, struct vss_task *vsst)
197 {
198 char *buf = (char *)fc->enc_buf;
199 struct fec_group *g = &fc->group;
200 struct fec_client_parms *p = fc->fcp;
201
202 write_u32(buf, FEC_MAGIC);
203
204 write_u8(buf + 4, p->slices_per_group + fc->num_extra_slices);
205 write_u8(buf + 5, p->data_slices_per_group + fc->num_extra_slices);
206 write_u32(buf + 6, g->num_header_slices? vsst->header_len : 0);
207
208 write_u32(buf + 10, g->num);
209 write_u32(buf + 14, g->bytes);
210
211 write_u8(buf + 18, fc->current_slice_num);
212 write_u16(buf + 20, p->max_slice_bytes - FEC_HEADER_SIZE);
213 write_u8(buf + 22, g->first_chunk? 0 : 1);
214 write_u8(buf + 23, vsst->header_len? 1 : 0);
215 memset(buf + 24, 0, 7);
216 }
217
218 static int need_audio_header(struct fec_client *fc, struct vss_task *vsst)
219 {
220 if (!mmd->current_chunk) {
221 tv_add(now, &vsst->header_interval, &fc->next_header_time);
222 return 0;
223 }
224 if (!vsst->header_buf)
225 return 0;
226 if (!vsst->header_len)
227 return 0;
228 if (fc->group.num && tv_diff(&fc->next_header_time, now, NULL) > 0)
229 return 0;
230 tv_add(now, &vsst->header_interval, &fc->next_header_time);
231 return 1;
232 }
233
234 static int num_slices(long unsigned bytes, struct fec_client *fc, uint8_t *result)
235 {
236 unsigned long m = fc->fcp->max_slice_bytes - FEC_HEADER_SIZE;
237 unsigned rv, redundant_slices = fc->fcp->slices_per_group
238 - fc->fcp->data_slices_per_group;
239
240 if (!m)
241 return -E_BAD_CT;
242 rv = (bytes + m - 1) / m;
243 if (rv + redundant_slices > 255)
244 return -E_BAD_CT;
245 *result = rv;
246 return 1;
247 }
248
249 /* set group start and group duration */
250 static void set_group_timing(struct fec_client *fc, struct fec_group *g)
251 {
252 struct timeval *chunk_tv = vss_chunk_time();
253
254 tv_scale(g->num_chunks, chunk_tv, &g->duration);
255 tv_divide(fc->fcp->slices_per_group + fc->num_extra_slices,
256 &g->duration, &g->slice_duration);
257 PARA_DEBUG_LOG("durations (group/chunk/slice): %lu/%lu/%lu\n",
258 tv2ms(&g->duration), tv2ms(chunk_tv), tv2ms(&g->slice_duration));
259 }
260
261 static int setup_next_fec_group(struct fec_client *fc, struct vss_task *vsst)
262 {
263 int ret, i, k, data_slices;
264 size_t len;
265 const char *buf, *start_buf;
266 struct fec_group *g = &fc->group;
267 unsigned slice_bytes = fc->fcp->max_slice_bytes - FEC_HEADER_SIZE;
268 uint32_t max_data_size;
269
270 if (fc->first_stream_chunk < 0) {
271 uint8_t hs, ds; /* needed header/data slices */
272 uint8_t rs = fc->fcp->slices_per_group
273 - fc->fcp->data_slices_per_group; /* redundant slices */
274 int n;
275
276 ret = num_slices(vsst->header_len, fc, &hs);
277 if (ret < 0)
278 return ret;
279 ret = num_slices(afh_get_largest_chunk_size(&mmd->afd.afhi),
280 fc, &ds);
281 if (ret < 0)
282 return ret;
283 k = (int)hs + ds;
284 if (k > 255)
285 return -E_BAD_CT;
286 if (k < fc->fcp->data_slices_per_group)
287 k = fc->fcp->data_slices_per_group;
288 n = k + rs;
289 fc->num_extra_slices = k - fc->fcp->data_slices_per_group;
290 PARA_NOTICE_LOG("fec parms %d:%d:%d (%d extra slices)\n",
291 slice_bytes, k, n, fc->num_extra_slices);
292 fec_free(fc->parms);
293 fc->src_data = para_realloc(fc->src_data, k * sizeof(char *));
294 ret = fec_new(k, n, &fc->parms);
295 if (ret < 0)
296 return ret;
297 fc->stream_start = *now;
298 fc->first_stream_chunk = mmd->current_chunk;
299 g->first_chunk = mmd->current_chunk;
300 g->num = 0;
301 g->start = *now;
302 } else {
303 struct timeval tmp;
304 if (g->first_chunk + g->num_chunks >= mmd->afd.afhi.chunks_total)
305 return 0;
306 /*
307 * Start and duration of this group depend only on the previous
308 * group. Compute the new group start as g->start += g->duration.
309 */
310 tmp = g->start;
311 tv_add(&tmp, &g->duration, &g->start);
312 k = fc->fcp->data_slices_per_group + fc->num_extra_slices;
313 set_group_timing(fc, g);
314 g->first_chunk += g->num_chunks;
315 g->num++;
316 }
317 if (need_audio_header(fc, vsst)) {
318 ret = num_slices(vsst->header_len, fc, &g->num_header_slices);
319 if (ret < 0)
320 return ret;
321 } else
322 g->num_header_slices = 0;
323 afh_get_chunk(g->first_chunk, &mmd->afd.afhi, vsst->map, &start_buf,
324 &len);
325 data_slices = k - g->num_header_slices;
326 assert(data_slices);
327 max_data_size = slice_bytes * data_slices;
328 g->bytes = 0;
329 for (i = g->first_chunk; i < mmd->afd.afhi.chunks_total; i++) {
330 afh_get_chunk(i, &mmd->afd.afhi, vsst->map, &buf, &len);
331 if (g->bytes + len > max_data_size)
332 break;
333 g->bytes += len;
334 }
335 g->num_chunks = i - g->first_chunk;
336 assert(g->num_chunks);
337 fc->current_slice_num = 0;
338 if (g->num == 0)
339 set_group_timing(fc, g);
340
341 /* setup header slices */
342 buf = vsst->header_buf;
343 for (i = 0; i < g->num_header_slices; i++) {
344 fc->src_data[i] = (const unsigned char *)buf;
345 buf += slice_bytes;
346 }
347
348 /* setup data slices */
349 buf = start_buf;
350 for (i = g->num_header_slices; i < k; i++) {
351 if (buf + slice_bytes > vsst->map + mmd->size)
352 /*
353 * Can not use the memory mapped audio file for this
354 * slice as it goes beyond the map. This slice will not
355 * be fully used.
356 */
357 break;
358 fc->src_data[i] = (const unsigned char *)buf;
359 buf += slice_bytes;
360 }
361 if (i < k) {
362 uint32_t payload_size = vsst->map + mmd->size - buf;
363 memcpy(fc->extra_src_buf, buf, payload_size);
364 fc->src_data[i] = fc->extra_src_buf;
365 i++;
366 /* use arbitrary data for all remaining slices */
367 buf = vsst->map;
368 for (; i < k; i++)
369 fc->src_data[i] = (const unsigned char *)buf;
370 }
371 PARA_DEBUG_LOG("FEC group %d: %d chunks (%d - %d), "
372 "%d header slices, %d data slices\n",
373 g->num, g->num_chunks, g->first_chunk,
374 g->first_chunk + g->num_chunks - 1,
375 g->num_header_slices, data_slices
376 );
377 return 1;
378 }
379
380 static int compute_next_fec_slice(struct fec_client *fc, struct vss_task *vsst)
381 {
382 if (fc->first_stream_chunk < 0 || fc->current_slice_num
383 == fc->fcp->slices_per_group + fc->num_extra_slices) {
384 int ret = setup_next_fec_group(fc, vsst);
385 if (ret == 0)
386 return 0;
387 if (ret < 0) {
388 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
389 PARA_ERROR_LOG("FEC client temporarily disabled\n");
390 fc->state = FEC_STATE_DISABLED;
391 return ret;
392 }
393 }
394 write_fec_header(fc, vsst);
395 fec_encode(fc->parms, fc->src_data, fc->enc_buf + FEC_HEADER_SIZE,
396 fc->current_slice_num,
397 fc->fcp->max_slice_bytes - FEC_HEADER_SIZE);
398 return 1;
399 }
400
401 /**
402 * Return a buffer that marks the end of the stream.
403 *
404 * \param buf Result pointer.
405 * \return The length of the eof buffer.
406 *
407 * This is used for (multicast) udp streaming where closing the socket on the
408 * sender might not give rise to an eof condition at the peer.
409 */
410 size_t vss_get_fec_eof_packet(const char **buf)
411 {
412 static const char fec_eof_packet[FEC_HEADER_SIZE] = FEC_EOF_PACKET;
413 *buf = fec_eof_packet;
414 return FEC_HEADER_SIZE;
415 }
416
417 /**
418 * Add one entry to the list of active fec clients.
419 *
420 * \param sc Generic sender_client data of the transport layer.
421 * \param fcp FEC parameters as supplied by the transport layer.
422 *
423 * \return Newly allocated fec_client struct.
424 */
425 struct fec_client *vss_add_fec_client(struct sender_client *sc,
426 struct fec_client_parms *fcp)
427 {
428 struct fec_client *fc = para_calloc(sizeof(*fc));
429
430 fc->sc = sc;
431 fc->fcp = fcp;
432 para_list_add(&fc->node, &fec_client_list);
433 return fc;
434 }
435
436 /**
437 * Remove one entry from the list of active fec clients.
438 *
439 * \param fc The client to be removed.
440 */
441 void vss_del_fec_client(struct fec_client *fc)
442 {
443 list_del(&fc->node);
444 free(fc->src_data);
445 free(fc->enc_buf);
446 free(fc->extra_src_buf);
447 fec_free(fc->parms);
448 free(fc);
449 }
450
451 /*
452 * Compute if/when next slice is due. If it isn't due yet and \a diff is
453 * not \p Null, compute the time difference next - now, where
454 *
455 * next = stream_start + (first_group_chunk - first_stream_chunk)
456 * * chunk_time + slice_num * slice_time
457 */
458 static int next_slice_is_due(struct fec_client *fc, struct timeval *diff)
459 {
460 struct timeval tmp, next;
461 int ret;
462
463 if (fc->first_stream_chunk < 0)
464 return 1;
465 tv_scale(fc->current_slice_num, &fc->group.slice_duration, &tmp);
466 tv_add(&tmp, &fc->group.start, &next);
467 ret = tv_diff(&next, now, diff);
468 return ret < 0? 1 : 0;
469 }
470
471 static void compute_slice_timeout(struct timeval *timeout)
472 {
473 struct fec_client *fc;
474
475 list_for_each_entry(fc, &fec_client_list, node) {
476 struct timeval diff;
477
478 if (fc->state != FEC_STATE_READY_TO_RUN)
479 continue;
480 if (next_slice_is_due(fc, &diff)) {
481 timeout->tv_sec = 0;
482 timeout->tv_usec = 0;
483 return;
484 }
485 /* timeout = min(timeout, diff) */
486 if (tv_diff(&diff, timeout, NULL) < 0)
487 *timeout = diff;
488 }
489 }
490
491 static void set_eof_barrier(struct vss_task *vsst)
492 {
493 struct fec_client *fc;
494 struct timeval timeout = {1, 0}, *chunk_tv = vss_chunk_time();
495
496 if (!chunk_tv)
497 goto out;
498 list_for_each_entry(fc, &fec_client_list, node) {
499 struct timeval group_duration;
500
501 if (fc->state != FEC_STATE_READY_TO_RUN)
502 continue;
503 tv_scale(fc->group.num_chunks, chunk_tv, &group_duration);
504 if (tv_diff(&timeout, &group_duration, NULL) < 0)
505 timeout = group_duration;
506 }
507 out:
508 tv_add(now, &timeout, &vsst->eof_barrier);
509 }
510
511 /**
512 * Check if vss status flag \a P (playing) is set.
513 *
514 * \return Greater than zero if playing, zero otherwise.
515 *
516 */
517 unsigned int vss_playing(void)
518 {
519 return mmd->new_vss_status_flags & VSS_PLAYING;
520 }
521
522 /**
523 * Check if the \a N (next) status flag is set.
524 *
525 * \return Greater than zero if set, zero if not.
526 *
527 */
528 unsigned int vss_next(void)
529 {
530 return mmd->new_vss_status_flags & VSS_NEXT;
531 }
532
533 /**
534 * Check if a reposition request is pending.
535 *
536 * \return Greater than zero if true, zero otherwise.
537 *
538 */
539 unsigned int vss_repos(void)
540 {
541 return mmd->new_vss_status_flags & VSS_REPOS;
542 }
543
544 /**
545 * Check if the vss is currently paused.
546 *
547 * \return Greater than zero if paused, zero otherwise.
548 *
549 */
550 unsigned int vss_paused(void)
551 {
552 return !(mmd->new_vss_status_flags & VSS_NEXT)
553 && !(mmd->new_vss_status_flags & VSS_PLAYING);
554 }
555
556 /**
557 * Check if the vss is currently stopped.
558 *
559 * \return Greater than zero if paused, zero otherwise.
560 *
561 */
562 unsigned int vss_stopped(void)
563 {
564 return (mmd->new_vss_status_flags & VSS_NEXT)
565 && !(mmd->new_vss_status_flags & VSS_PLAYING);
566 }
567
568 static int chk_barrier(const char *bname, const struct timeval *barrier,
569 struct timeval *diff, int print_log)
570 {
571 long ms;
572
573 if (tv_diff(now, barrier, diff) > 0)
574 return 1;
575 ms = tv2ms(diff);
576 if (print_log && ms)
577 PARA_DEBUG_LOG("%s barrier: %lims left\n", bname, ms);
578 return -1;
579 }
580
581 /*
582 * != NULL: timeout for next chunk
583 * NULL: nothing to do
584 */
585 static struct timeval *vss_compute_timeout(struct vss_task *vsst)
586 {
587 static struct timeval the_timeout;
588 struct timeval next_chunk;
589
590 if (vss_next() && vsst->map) {
591 /* only sleep a bit, nec*/
592 the_timeout.tv_sec = 0;
593 the_timeout.tv_usec = 100;
594 return &the_timeout;
595 }
596 if (chk_barrier("autoplay_delay", &vsst->autoplay_barrier,
597 &the_timeout, 1) < 0)
598 return &the_timeout;
599 if (chk_barrier("eof", &vsst->eof_barrier, &the_timeout, 1) < 0)
600 return &the_timeout;
601 if (chk_barrier("data send", &vsst->data_send_barrier,
602 &the_timeout, 1) < 0)
603 return &the_timeout;
604 if (!vss_playing() || !vsst->map)
605 return NULL;
606 compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
607 &mmd->stream_start, &next_chunk);
608 if (chk_barrier("chunk", &next_chunk, &the_timeout, 0) >= 0) {
609 /* chunk is due or bof */
610 the_timeout.tv_sec = 0;
611 the_timeout.tv_usec = 0;
612 return &the_timeout;
613 }
614 /* compute min of current timeout and next slice time */
615 compute_slice_timeout(&the_timeout);
616 return &the_timeout;
617 }
618
619 static void vss_eof(struct vss_task *vsst)
620 {
621
622 if (!vsst->map)
623 return;
624 if (mmd->new_vss_status_flags & VSS_NOMORE)
625 mmd->new_vss_status_flags = VSS_NEXT;
626 set_eof_barrier(vsst);
627 para_munmap(vsst->map, mmd->size);
628 vsst->map = NULL;
629 mmd->chunks_sent = 0;
630 //mmd->offset = 0;
631 mmd->afd.afhi.seconds_total = 0;
632 mmd->afd.afhi.chunk_tv.tv_sec = 0;
633 mmd->afd.afhi.chunk_tv.tv_usec = 0;
634 free(mmd->afd.afhi.chunk_table);
635 mmd->afd.afhi.chunk_table = NULL;
636 mmd->mtime = 0;
637 mmd->size = 0;
638 mmd->events++;
639 }
640
641 /**
642 * Get the list of all supported audio formats.
643 *
644 * \return Aa space separated list of all supported audio formats
645 * It is not allocated at runtime, i.e. there is no need to free
646 * the returned string in the caller.
647 */
648 const char *supported_audio_formats(void)
649 {
650 return SUPPORTED_AUDIO_FORMATS;
651 }
652
653 static int need_to_request_new_audio_file(struct vss_task *vsst)
654 {
655 struct timeval diff;
656
657 if (vsst->map) /* have audio file */
658 return 0;
659 if (!vss_playing()) /* don't need one */
660 return 0;
661 if (mmd->new_vss_status_flags & VSS_NOMORE)
662 return 0;
663 if (vsst->afsss == AFS_SOCKET_AFD_PENDING) /* already requested one */
664 return 0;
665 if (chk_barrier("autoplay_delay", &vsst->autoplay_barrier,
666 &diff, 1) < 0)
667 return 0;
668 return 1;
669 }
670
671 static void set_mmd_offset(void)
672 {
673 struct timeval offset;
674 tv_scale(mmd->current_chunk, &mmd->afd.afhi.chunk_tv, &offset);
675 mmd->offset = tv2ms(&offset);
676 }
677
678 /**
679 * Compute the timeout for the main select-loop of the scheduler.
680 *
681 * \param s Pointer to the server scheduler.
682 * \param t Pointer to the vss task structure.
683 *
684 * Before the timeout is computed, the current vss status flags are evaluated
685 * and acted upon by calling appropriate functions from the lower layers.
686 * Possible actions include
687 *
688 * - request a new audio file from afs,
689 * - shutdown of all senders (stop/pause command),
690 * - reposition the stream (ff/jmp command).
691 */
692 static void vss_pre_select(struct sched *s, struct task *t)
693 {
694 int i;
695 struct timeval *tv, diff;
696 struct vss_task *vsst = container_of(t, struct vss_task, task);
697
698 if (!vsst->map || vss_next() || vss_paused() || vss_repos()) {
699 struct fec_client *fc, *tmp;
700 for (i = 0; senders[i].name; i++)
701 if (senders[i].shutdown_clients)
702 senders[i].shutdown_clients();
703 list_for_each_entry_safe(fc, tmp, &fec_client_list, node) {
704 fc->first_stream_chunk = -1;
705 fc->state = FEC_STATE_NONE;
706 }
707 mmd->stream_start.tv_sec = 0;
708 mmd->stream_start.tv_usec = 0;
709 }
710 if (vss_next())
711 vss_eof(vsst);
712 else if (vss_paused()) {
713 if (mmd->chunks_sent)
714 set_eof_barrier(vsst);
715 mmd->chunks_sent = 0;
716 } else if (vss_repos()) {
717 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
718 set_eof_barrier(vsst);
719 mmd->chunks_sent = 0;
720 mmd->current_chunk = mmd->repos_request;
721 mmd->new_vss_status_flags &= ~VSS_REPOS;
722 set_mmd_offset();
723 }
724 if (need_to_request_new_audio_file(vsst)) {
725 PARA_DEBUG_LOG("ready and playing, but no audio file\n");
726 para_fd_set(vsst->afs_socket, &s->wfds, &s->max_fileno);
727 vsst->afsss = AFS_SOCKET_CHECK_FOR_WRITE;
728 } else
729 para_fd_set(vsst->afs_socket, &s->rfds, &s->max_fileno);
730 for (i = 0; senders[i].name; i++) {
731 if (!senders[i].pre_select)
732 continue;
733 senders[i].pre_select(&s->max_fileno, &s->rfds, &s->wfds);
734 }
735 tv = vss_compute_timeout(vsst);
736 if (tv && tv_diff(tv, &s->timeout, &diff) < 0)
737 s->timeout = *tv;
738 }
739
740 static int recv_afs_msg(int afs_socket, int *fd, uint32_t *code, uint32_t *data)
741 {
742 char control[255], buf[8];
743 struct msghdr msg = {.msg_iov = NULL};
744 struct cmsghdr *cmsg;
745 struct iovec iov;
746 int ret = 0;
747
748 *fd = -1;
749 iov.iov_base = buf;
750 iov.iov_len = sizeof(buf);
751 msg.msg_iov = &iov;
752 msg.msg_iovlen = 1;
753 msg.msg_control = control;
754 msg.msg_controllen = sizeof(control);
755 memset(buf, 0, sizeof(buf));
756 ret = recvmsg(afs_socket, &msg, 0);
757 if (ret < 0)
758 return -ERRNO_TO_PARA_ERROR(errno);
759 if (iov.iov_len != sizeof(buf))
760 return -E_AFS_SHORT_READ;
761 *code = *(uint32_t*)buf;
762 *data = *(uint32_t*)(buf + 4);
763 for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
764 if (cmsg->cmsg_level != SOL_SOCKET
765 || cmsg->cmsg_type != SCM_RIGHTS)
766 continue;
767 if ((cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int) != 1)
768 continue;
769 *fd = *(int *)CMSG_DATA(cmsg);
770 }
771 return 1;
772 }
773
774 static void recv_afs_result(struct vss_task *vsst, fd_set *rfds)
775 {
776 int ret, passed_fd, shmid;
777 uint32_t afs_code = 0, afs_data = 0;
778 struct stat statbuf;
779
780 if (!FD_ISSET(vsst->afs_socket, rfds))
781 return;
782 ret = recv_afs_msg(vsst->afs_socket, &passed_fd, &afs_code, &afs_data);
783 if (ret == -ERRNO_TO_PARA_ERROR(EAGAIN))
784 return;
785 if (ret < 0)
786 goto err;
787 vsst->afsss = AFS_SOCKET_READY;
788 PARA_DEBUG_LOG("fd: %d, code: %u, shmid: %u\n", passed_fd, afs_code,
789 afs_data);
790 ret = -E_NOFD;
791 if (afs_code != NEXT_AUDIO_FILE)
792 goto err;
793 if (passed_fd < 0)
794 goto err;
795 shmid = afs_data;
796 ret = load_afd(shmid, &mmd->afd);
797 if (ret < 0)
798 goto err;
799 shm_destroy(shmid);
800 ret = fstat(passed_fd, &statbuf);
801 if (ret < 0) {
802 PARA_ERROR_LOG("fstat error:\n");
803 ret = -ERRNO_TO_PARA_ERROR(errno);
804 goto err;
805 }
806 mmd->size = statbuf.st_size;
807 mmd->mtime = statbuf.st_mtime;
808 ret = para_mmap(mmd->size, PROT_READ, MAP_PRIVATE, passed_fd,
809 0, &vsst->map);
810 if (ret < 0)
811 goto err;
812 close(passed_fd);
813 mmd->chunks_sent = 0;
814 mmd->current_chunk = 0;
815 mmd->offset = 0;
816 mmd->events++;
817 mmd->num_played++;
818 mmd->new_vss_status_flags &= (~VSS_NEXT);
819 afh_get_header(&mmd->afd.afhi, vsst->map, &vsst->header_buf,
820 &vsst->header_len);
821 return;
822 err:
823 free(mmd->afd.afhi.chunk_table);
824 if (passed_fd >= 0)
825 close(passed_fd);
826 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
827 mmd->new_vss_status_flags = VSS_NEXT;
828 }
829
830 static int initialize_fec_client(struct fec_client *fc)
831 {
832 int ret;
833 struct fec_client_parms *fcp = fc->fcp;
834
835 if (fcp->init_fec) {
836 /*
837 * Set the maximum slice size to the Maximum Packet Size if the
838 * transport protocol allows to determine this value. The user
839 * can specify a slice size up to this value.
840 */
841 ret = fcp->init_fec(fc->sc);
842 if (ret < 0)
843 return ret;
844 if (!fcp->max_slice_bytes || fcp->max_slice_bytes > ret)
845 fcp->max_slice_bytes = ret;
846 }
847 if (fcp->max_slice_bytes < FEC_HEADER_SIZE + fcp->data_slices_per_group)
848 return -ERRNO_TO_PARA_ERROR(EINVAL);
849 ret = fec_new(fcp->data_slices_per_group, fcp->slices_per_group,
850 &fc->parms);
851 if (ret < 0)
852 goto err;
853 fc->first_stream_chunk = -1; /* stream not yet started */
854 fc->src_data = para_malloc(fc->fcp->slices_per_group * sizeof(char *));
855 fc->enc_buf = para_calloc(fc->fcp->max_slice_bytes);
856 fc->num_extra_slices = 0;
857 fc->extra_src_buf = para_calloc(fc->fcp->max_slice_bytes);
858 fc->next_header_time.tv_sec = 0;
859 fc->state = FEC_STATE_READY_TO_RUN;
860 return 1;
861 err:
862 fec_free(fc->parms);
863 return ret;
864 }
865
866 /**
867 * Main sending function.
868 *
869 * This function gets called from vss_post_select(). It checks whether the next
870 * chunk of data should be pushed out. It obtains a pointer to the data to be
871 * sent out as well as its length from mmd->afd.afhi. This information is then
872 * passed to each supported sender's send() function as well as to the send()
873 * functions of each registered fec client.
874 */
875 static void vss_send(struct vss_task *vsst)
876 {
877 int ret, i, fec_active = 0;
878 struct timeval due;
879 struct fec_client *fc, *tmp_fc;
880
881 if (!vsst->map || !vss_playing())
882 return;
883 if (chk_barrier("eof", &vsst->eof_barrier, &due, 1) < 0)
884 return;
885 if (chk_barrier("data send", &vsst->data_send_barrier,
886 &due, 1) < 0)
887 return;
888 list_for_each_entry_safe(fc, tmp_fc, &fec_client_list, node) {
889 switch (fc->state) {
890 case FEC_STATE_DISABLED:
891 continue;
892 case FEC_STATE_NONE:
893 ret = initialize_fec_client(fc);
894 if (ret < 0) {
895 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
896 continue;
897 }
898 /* fall through */
899 case FEC_STATE_READY_TO_RUN:
900 break;
901 }
902 if (!next_slice_is_due(fc, NULL)) {
903 fec_active = 1;
904 continue;
905 }
906 if (compute_next_fec_slice(fc, vsst) <= 0)
907 continue;
908 PARA_DEBUG_LOG("sending %d:%d (%u bytes)\n", fc->group.num,
909 fc->current_slice_num, fc->fcp->max_slice_bytes);
910 fc->fcp->send_fec(fc->sc, (char *)fc->enc_buf,
911 fc->fcp->max_slice_bytes);
912 fc->current_slice_num++;
913 fec_active = 1;
914 }
915 if (mmd->current_chunk >= mmd->afd.afhi.chunks_total) { /* eof */
916 if (!fec_active)
917 mmd->new_vss_status_flags |= VSS_NEXT;
918 return;
919 }
920 compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
921 &mmd->stream_start, &due);
922 if (tv_diff(&due, now, NULL) <= 0) {
923 const char *buf;
924 size_t len;
925
926 if (!mmd->chunks_sent) {
927 mmd->stream_start = *now;
928 mmd->events++;
929 set_mmd_offset();
930 }
931 /*
932 * We call the send function also in case of empty chunks as
933 * they might have still some data queued which can be sent in
934 * this case.
935 */
936 afh_get_chunk(mmd->current_chunk, &mmd->afd.afhi, vsst->map,
937 &buf, &len);
938 for (i = 0; senders[i].name; i++) {
939 if (!senders[i].send)
940 continue;
941 senders[i].send(mmd->current_chunk, mmd->chunks_sent,
942 buf, len, vsst->header_buf, vsst->header_len);
943 }
944 mmd->chunks_sent++;
945 mmd->current_chunk++;
946 }
947 }
948
949 static void vss_post_select(struct sched *s, struct task *t)
950 {
951 int ret, i;
952 struct vss_task *vsst = container_of(t, struct vss_task, task);
953
954
955 if (mmd->sender_cmd_data.cmd_num >= 0) {
956 int num = mmd->sender_cmd_data.cmd_num,
957 sender_num = mmd->sender_cmd_data.sender_num;
958
959 if (senders[sender_num].client_cmds[num])
960 senders[sender_num].client_cmds[num](&mmd->sender_cmd_data);
961 mmd->sender_cmd_data.cmd_num = -1;
962 }
963 if (vsst->afsss != AFS_SOCKET_CHECK_FOR_WRITE)
964 recv_afs_result(vsst, &s->rfds);
965 else if (FD_ISSET(vsst->afs_socket, &s->wfds)) {
966 PARA_NOTICE_LOG("requesting new fd from afs\n");
967 ret = send_buffer(vsst->afs_socket, "new");
968 if (ret < 0)
969 PARA_CRIT_LOG("%s\n", para_strerror(-ret));
970 else
971 vsst->afsss = AFS_SOCKET_AFD_PENDING;
972 }
973 for (i = 0; senders[i].name; i++) {
974 if (!senders[i].post_select)
975 continue;
976 senders[i].post_select(&s->rfds, &s->wfds);
977 }
978 if ((vss_playing() && !(mmd->vss_status_flags & VSS_PLAYING)) ||
979 (vss_next() && vss_playing()))
980 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
981 vss_send(vsst);
982 }
983
984 /**
985 * Initialize the virtual streaming system task.
986 *
987 * \param afs_socket The fd for communication with afs.
988 *
989 * This also initializes all supported senders and starts streaming
990 * if the --autoplay command line flag was given.
991 */
992 void init_vss_task(int afs_socket)
993 {
994 static struct vss_task vss_task_struct, *vsst = &vss_task_struct;
995 int i;
996 char *hn = para_hostname(), *home = para_homedir();
997 long unsigned announce_time = conf.announce_time_arg > 0?
998 conf.announce_time_arg : 300,
999 autoplay_delay = conf.autoplay_delay_arg > 0?
1000 conf.autoplay_delay_arg : 0;
1001 vsst->header_interval.tv_sec = 5; /* should this be configurable? */
1002 vsst->afs_socket = afs_socket;
1003 vsst->task.pre_select = vss_pre_select;
1004 vsst->task.post_select = vss_post_select;
1005 ms2tv(announce_time, &vsst->announce_tv);
1006 PARA_INFO_LOG("announce timeval: %lums\n", tv2ms(&vsst->announce_tv));
1007 INIT_LIST_HEAD(&fec_client_list);
1008 for (i = 0; senders[i].name; i++) {
1009 PARA_NOTICE_LOG("initializing %s sender\n", senders[i].name);
1010 senders[i].init(&senders[i]);
1011 }
1012 free(hn);
1013 free(home);
1014 mmd->sender_cmd_data.cmd_num = -1;
1015 if (conf.autoplay_given) {
1016 struct timeval tmp;
1017 mmd->vss_status_flags |= VSS_PLAYING;
1018 mmd->new_vss_status_flags |= VSS_PLAYING;
1019 ms2tv(autoplay_delay, &tmp);
1020 tv_add(now, &tmp, &vsst->autoplay_barrier);
1021 tv_add(&vsst->autoplay_barrier, &vsst->announce_tv,
1022 &vsst->data_send_barrier);
1023 }
1024 register_task(&vsst->task);
1025 }