FEC: Improve and simplify group timing.
[paraslash.git] / vss.c
1 /*
2 * Copyright (C) 1997-2009 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 <dirent.h>
15
16 #include "para.h"
17 #include "error.h"
18 #include "portable_io.h"
19 #include "fec.h"
20 #include "string.h"
21 #include "afh.h"
22 #include "afs.h"
23 #include "server.h"
24 #include "net.h"
25 #include "server.cmdline.h"
26 #include "list.h"
27 #include "vss.h"
28 #include "send.h"
29 #include "ipc.h"
30 #include "fd.h"
31 #include "sched.h"
32
33 extern struct misc_meta_data *mmd;
34
35 extern void dccp_send_init(struct sender *);
36 extern void http_send_init(struct sender *);
37 extern void udp_send_init(struct sender *);
38
39 /** The list of supported senders. */
40 struct sender senders[] = {
41 {
42 .name = "http",
43 .init = http_send_init,
44 },
45 {
46 .name = "dccp",
47 .init = dccp_send_init,
48 },
49 {
50 .name = "udp",
51 .init = udp_send_init,
52 },
53 {
54 .name = NULL,
55 }
56 };
57
58 /** The possible states of the afs socket. */
59 enum afs_socket_status {
60 /** Socket is inactive. */
61 AFS_SOCKET_READY,
62 /** Socket fd was included in the write fd set for select(). */
63 AFS_SOCKET_CHECK_FOR_WRITE,
64 /** vss wrote a request to the socket and waits for reply from afs. */
65 AFS_SOCKET_AFD_PENDING
66 };
67
68 /** The task structure for the virtual streaming system. */
69 struct vss_task {
70 /** Copied from the -announce_time command line option. */
71 struct timeval announce_tv;
72 /** End of the announcing interval. */
73 struct timeval data_send_barrier;
74 /** End of the EOF interval. */
75 struct timeval eof_barrier;
76 /** Only used if --autoplay_delay was given. */
77 struct timeval autoplay_barrier;
78 /** Used for afs-server communication. */
79 int afs_socket;
80 /** The current state of \a afs_socket. */
81 enum afs_socket_status afsss;
82 /** The memory mapped audio file. */
83 char *map;
84 /** Used by the scheduler. */
85 struct task task;
86 /** Pointer to the header of the mapped audio file. */
87 const char *header_buf;
88 /** Length of the audio file header. */
89 size_t header_len;
90 /** Time between audio file headers are sent. */
91 struct timeval header_interval;
92 };
93
94 /**
95 * The list of currently connected fec clients.
96 *
97 * Senders may use \ref vss_add_fec_client() to add entries to the list.
98 */
99 static struct list_head fec_client_list;
100
101 /**
102 * Data associated with one FEC group.
103 *
104 * A FEC group consists of a fixed number of slices and this number is given by
105 * the \a slices_per_group parameter of struct \ref fec_client_parms. Each FEC
106 * group contains a number of chunks of the current audio file.
107 *
108 * FEC slices directly correspond to the data packages sent by the paraslash
109 * senders that use FEC. Each slice is identified by its group number and its
110 * number within the group. All slices have the same size, but the last slice
111 * of the group may not be filled entirely.
112 */
113 struct fec_group {
114 /** The number of the FEC group. */
115 uint32_t num;
116 /** Number of bytes in this group. */
117 uint32_t bytes;
118 /** The first chunk of the current audio file belonging to the group. */
119 uint32_t first_chunk;
120 /** The number of chunks contained in this group. */
121 uint32_t num_chunks;
122 /** When the first chunk was sent. */
123 struct timeval start;
124 /** The duration of the full group. */
125 struct timeval duration;
126 /** The group duration divided by the number of slices. */
127 struct timeval slice_duration;
128 /** Group contains the audio file header that occupies that many slices. */
129 uint8_t num_header_slices;
130 };
131
132 /**
133 * Describes one connected FEC client.
134 */
135 struct fec_client {
136 /** If negative, this client is temporarily disabled. */
137 int error;
138 /** Parameters requested by the client. */
139 struct fec_client_parms *fcp;
140 /** Used by the core FEC code. */
141 struct fec_parms *parms;
142 /** The position of this client in the fec client list. */
143 struct list_head node;
144 /** When the first slice for this client was sent. */
145 struct timeval stream_start;
146 /** The first chunk sent to this FEC client. */
147 int first_stream_chunk;
148 /** Describes the current group. */
149 struct fec_group group;
150 /** The current slice. */
151 uint8_t current_slice_num;
152 /** The data to be FEC-encoded (point to a region within the mapped audio file). */
153 const unsigned char **src_data;
154 /** Last time an audio header was sent. */
155 struct timeval next_header_time;
156 /** Used for the last source pointer of an audio file. */
157 unsigned char *extra_src_buf;
158 /** Extra slices needed to store largest chunk + header. */
159 int num_extra_slices;
160 /** Contains the FEC-encoded data. */
161 unsigned char *enc_buf;
162 };
163
164 /**
165 * Get the chunk time of the current audio file.
166 *
167 * \return A pointer to a struct containing the chunk time, or NULL,
168 * if currently no audio file is selected.
169 */
170 struct timeval *vss_chunk_time(void)
171 {
172 if (mmd->afd.afhi.chunk_tv.tv_sec == 0 &&
173 mmd->afd.afhi.chunk_tv.tv_usec == 0)
174 return NULL;
175 return &mmd->afd.afhi.chunk_tv;
176 }
177
178 /**
179 * Write a fec header to a buffer.
180 *
181 * \param buf The buffer to write to.
182 * \param h The fec header to write.
183 */
184 static void write_fec_header(struct fec_client *fc, struct vss_task *vsst)
185 {
186 char *buf = (char *)fc->enc_buf;
187 struct fec_group *g = &fc->group;
188 struct fec_client_parms *p = fc->fcp;
189
190 write_u32(buf, FEC_MAGIC);
191
192 write_u8(buf + 4, p->slices_per_group + fc->num_extra_slices);
193 write_u8(buf + 5, p->data_slices_per_group + fc->num_extra_slices);
194 write_u32(buf + 6, g->num_header_slices? vsst->header_len : 0);
195
196 write_u32(buf + 10, g->num);
197 write_u32(buf + 14, g->bytes);
198
199 write_u8(buf + 18, fc->current_slice_num);
200 write_u16(buf + 20, p->max_slice_bytes - FEC_HEADER_SIZE);
201 write_u8(buf + 22, g->first_chunk? 0 : 1);
202 write_u8(buf + 23, vsst->header_len? 1 : 0);
203 memset(buf + 24, 0, 7);
204 }
205
206 static int need_audio_header(struct fec_client *fc, struct vss_task *vsst)
207 {
208 if (!mmd->current_chunk) {
209 tv_add(now, &vsst->header_interval, &fc->next_header_time);
210 return 0;
211 }
212 if (!vsst->header_buf)
213 return 0;
214 if (!vsst->header_len)
215 return 0;
216 if (fc->group.num && tv_diff(&fc->next_header_time, now, NULL) > 0)
217 return 0;
218 tv_add(now, &vsst->header_interval, &fc->next_header_time);
219 return 1;
220 }
221
222 static int num_slices(long unsigned bytes, struct fec_client *fc, uint8_t *result)
223 {
224 unsigned long m = fc->fcp->max_slice_bytes - FEC_HEADER_SIZE;
225 unsigned rv, redundant_slices = fc->fcp->slices_per_group
226 - fc->fcp->data_slices_per_group;
227
228 if (!m)
229 return -E_BAD_CT;
230 rv = (bytes + m - 1) / m;
231 if (rv + redundant_slices > 255)
232 return -E_BAD_CT;
233 *result = rv;
234 return 1;
235 }
236
237 /* set group start and group duration */
238 static void set_group_timing(struct fec_client *fc, struct fec_group *g)
239 {
240 struct timeval *chunk_tv = vss_chunk_time();
241
242 tv_scale(g->num_chunks, chunk_tv, &g->duration);
243 tv_divide(fc->fcp->slices_per_group + fc->num_extra_slices,
244 &g->duration, &g->slice_duration);
245 PARA_DEBUG_LOG("durations (group/chunk/slice): %lu/%lu/%lu\n",
246 tv2ms(&g->duration), tv2ms(chunk_tv), tv2ms(&g->slice_duration));
247 }
248
249 static int setup_next_fec_group(struct fec_client *fc, struct vss_task *vsst)
250 {
251 int ret, i, k, data_slices;
252 size_t len;
253 const char *buf, *start_buf;
254 struct fec_group *g = &fc->group;
255 unsigned slice_bytes = fc->fcp->max_slice_bytes - FEC_HEADER_SIZE;
256 uint32_t max_data_size;
257
258 if (fc->first_stream_chunk < 0) {
259 uint8_t hs, ds; /* needed header/data slices */
260 uint8_t rs = fc->fcp->slices_per_group
261 - fc->fcp->data_slices_per_group; /* redundant slices */
262 int n;
263
264 ret = num_slices(vsst->header_len, fc, &hs);
265 if (ret < 0)
266 return ret;
267 ret = num_slices(afh_get_largest_chunk_size(&mmd->afd.afhi),
268 fc, &ds);
269 if (ret < 0)
270 return ret;
271 k = (int)hs + ds;
272 if (k > 255)
273 return -E_BAD_CT;
274 if (k < fc->fcp->data_slices_per_group)
275 k = fc->fcp->data_slices_per_group;
276 n = k + rs;
277 fc->num_extra_slices = k - fc->fcp->data_slices_per_group;
278 PARA_NOTICE_LOG("fec parms %d:%d:%d (%d extra slices)\n",
279 slice_bytes, k, n, fc->num_extra_slices);
280 fec_free(fc->parms);
281 fc->src_data = para_realloc(fc->src_data, k * sizeof(char *));
282 ret = fec_new(k, n, &fc->parms);
283 if (ret < 0)
284 return ret;
285 fc->stream_start = *now;
286 fc->first_stream_chunk = mmd->current_chunk;
287 g->first_chunk = mmd->current_chunk;
288 g->num = 0;
289 g->start = *now;
290 } else {
291 /*
292 * Start and duration of this group depend only on the previous
293 * group. Compute the new group start as g->start += g->duration.
294 */
295 struct timeval tmp = g->start;
296 tv_add(&tmp, &g->duration, &g->start);
297 k = fc->fcp->data_slices_per_group + fc->num_extra_slices;
298 set_group_timing(fc, g);
299 g->first_chunk += g->num_chunks;
300 g->num++;
301 }
302 if (g->first_chunk >= mmd->afd.afhi.chunks_total)
303 return 0;
304 if (need_audio_header(fc, vsst)) {
305 ret = num_slices(vsst->header_len, fc, &g->num_header_slices);
306 if (ret < 0)
307 return ret;
308 } else
309 g->num_header_slices = 0;
310 afh_get_chunk(g->first_chunk, &mmd->afd.afhi, vsst->map, &start_buf,
311 &len);
312 data_slices = k - g->num_header_slices;
313 assert(data_slices);
314 max_data_size = slice_bytes * data_slices;
315 g->bytes = 0;
316 for (i = g->first_chunk; i < mmd->afd.afhi.chunks_total; i++) {
317 afh_get_chunk(i, &mmd->afd.afhi, vsst->map, &buf, &len);
318 if (g->bytes + len > max_data_size)
319 break;
320 g->bytes += len;
321 }
322 g->num_chunks = i - g->first_chunk;
323 assert(g->num_chunks);
324 fc->current_slice_num = 0;
325 if (g->num == 0)
326 set_group_timing(fc, g);
327
328 /* setup header slices */
329 buf = vsst->header_buf;
330 for (i = 0; i < g->num_header_slices; i++) {
331 fc->src_data[i] = (const unsigned char *)buf;
332 buf += slice_bytes;
333 }
334
335 /* setup data slices */
336 buf = start_buf;
337 for (i = g->num_header_slices; i < k; i++) {
338 if (buf + slice_bytes > vsst->map + mmd->size)
339 /*
340 * Can not use the memory mapped audio file for this
341 * slice as it goes beyond the map. This slice will not
342 * be fully used.
343 */
344 break;
345 fc->src_data[i] = (const unsigned char *)buf;
346 buf += slice_bytes;
347 }
348 if (i < k) {
349 uint32_t payload_size = vsst->map + mmd->size - buf;
350 memcpy(fc->extra_src_buf, buf, payload_size);
351 fc->src_data[i] = fc->extra_src_buf;
352 i++;
353 /* use arbitrary data for all remaining slices */
354 buf = vsst->map;
355 for (; i < k; i++)
356 fc->src_data[i] = (const unsigned char *)buf;
357 }
358 PARA_DEBUG_LOG("FEC group %d: %d chunks (%d - %d), "
359 "%d header slices, %d data slices\n",
360 g->num, g->num_chunks, g->first_chunk,
361 g->first_chunk + g->num_chunks - 1,
362 g->num_header_slices, data_slices
363 );
364 return 1;
365 }
366
367 static int compute_next_fec_slice(struct fec_client *fc, struct vss_task *vsst)
368 {
369 assert(fc->error >= 0);
370 if (fc->first_stream_chunk < 0 || fc->current_slice_num
371 == fc->fcp->slices_per_group + fc->num_extra_slices) {
372 int ret = setup_next_fec_group(fc, vsst);
373 if (ret == 0)
374 return 0;
375 if (ret < 0) {
376 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
377 PARA_ERROR_LOG("FEC client temporarily disabled\n");
378 fc->error = ret;
379 return fc->error;
380 }
381 }
382 write_fec_header(fc, vsst);
383 fec_encode(fc->parms, fc->src_data, fc->enc_buf + FEC_HEADER_SIZE,
384 fc->current_slice_num,
385 fc->fcp->max_slice_bytes - FEC_HEADER_SIZE);
386 return 1;
387 }
388
389 /**
390 * Return a buffer that marks the end of the stream.
391 *
392 * \param buf Result pointer.
393 * \return The length of the eof buffer.
394 *
395 * This is used for (multicast) udp streaming where closing the socket on the
396 * sender might not give rise to an eof condition at the peer.
397 */
398 size_t vss_get_fec_eof_packet(const char **buf)
399 {
400 static const char fec_eof_packet[FEC_HEADER_SIZE] = FEC_EOF_PACKET;
401 *buf = fec_eof_packet;
402 return FEC_HEADER_SIZE;
403 }
404
405 /**
406 * Add one entry to the list of active fec clients.
407 *
408 * \param fcp Describes the fec parameters to be used for this client.
409 * \param result An opaque pointer that must be used by remove the client later.
410 *
411 * \return Standard.
412 */
413 int vss_add_fec_client(struct fec_client_parms *fcp, struct fec_client **result)
414 {
415 int ret;
416 struct fec_client *fc;
417
418 if (fcp->max_slice_bytes < FEC_HEADER_SIZE + fcp->data_slices_per_group)
419 return -ERRNO_TO_PARA_ERROR(EINVAL);
420 fc = para_calloc(sizeof(*fc));
421 fc->fcp = fcp;
422 ret = fec_new(fcp->data_slices_per_group, fcp->slices_per_group,
423 &fc->parms);
424 if (ret < 0)
425 goto err;
426 fc->first_stream_chunk = -1; /* stream not yet started */
427 fc->src_data = para_malloc(fc->fcp->slices_per_group * sizeof(char *));
428 fc->enc_buf = para_calloc(fc->fcp->max_slice_bytes);
429 fc->num_extra_slices = 0;
430 fc->extra_src_buf = para_calloc(fc->fcp->max_slice_bytes);
431 fc->next_header_time.tv_sec = 0;
432 para_list_add(&fc->node, &fec_client_list);
433 *result = fc;
434 return 1;
435 err:
436 fec_free(fc->parms);
437 free(fc);
438 *result = NULL;
439 return ret;
440 }
441
442 /**
443 * Remove one entry from the list of active fec clients.
444 *
445 * \param fc The client to be removed.
446 */
447 void vss_del_fec_client(struct fec_client *fc)
448 {
449 list_del(&fc->node);
450 free(fc->src_data);
451 free(fc->enc_buf);
452 free(fc->extra_src_buf);
453 fec_free(fc->parms);
454 free(fc);
455 }
456
457 /*
458 * Compute if/when next slice is due. If it isn't due yet and \a diff is
459 * not \p Null, compute the time difference next - now, where
460 *
461 * next = stream_start + (first_group_chunk - first_stream_chunk)
462 * * chunk_time + slice_num * slice_time
463 */
464 static int next_slice_is_due(struct fec_client *fc, struct timeval *diff)
465 {
466 struct timeval tmp, next;
467 int ret;
468
469 if (fc->first_stream_chunk < 0)
470 return 1;
471 tv_scale(fc->current_slice_num, &fc->group.slice_duration, &tmp);
472 tv_add(&tmp, &fc->group.start, &next);
473 ret = tv_diff(&next, now, diff);
474 return ret < 0? 1 : 0;
475 }
476
477 static void compute_slice_timeout(struct timeval *timeout)
478 {
479 struct fec_client *fc;
480
481 assert(vss_playing());
482 list_for_each_entry(fc, &fec_client_list, node) {
483 struct timeval diff;
484
485 if (fc->error < 0)
486 continue;
487 if (next_slice_is_due(fc, &diff)) {
488 timeout->tv_sec = 0;
489 timeout->tv_usec = 0;
490 return;
491 }
492 /* timeout = min(timeout, diff) */
493 if (tv_diff(&diff, timeout, NULL) < 0)
494 *timeout = diff;
495 }
496 }
497
498 static void set_eof_barrier(struct vss_task *vsst)
499 {
500 struct fec_client *fc;
501 struct timeval timeout = mmd->afd.afhi.eof_tv,
502 *chunk_tv = vss_chunk_time();
503
504 if (!chunk_tv)
505 goto out;
506 list_for_each_entry(fc, &fec_client_list, node) {
507 struct timeval group_duration;
508
509 if (fc->error < 0)
510 continue;
511 tv_scale(fc->group.num_chunks, chunk_tv, &group_duration);
512 if (tv_diff(&timeout, &group_duration, NULL) < 0)
513 timeout = group_duration;
514 }
515 out:
516 tv_add(now, &timeout, &vsst->eof_barrier);
517 }
518
519 /**
520 * Check if vss status flag \a P (playing) is set.
521 *
522 * \return Greater than zero if playing, zero otherwise.
523 *
524 */
525 unsigned int vss_playing(void)
526 {
527 return mmd->new_vss_status_flags & VSS_PLAYING;
528 }
529
530 /**
531 * Check if the \a N (next) status flag is set.
532 *
533 * \return Greater than zero if set, zero if not.
534 *
535 */
536 unsigned int vss_next(void)
537 {
538 return mmd->new_vss_status_flags & VSS_NEXT;
539 }
540
541 /**
542 * Check if a reposition request is pending.
543 *
544 * \return Greater than zero if true, zero otherwise.
545 *
546 */
547 unsigned int vss_repos(void)
548 {
549 return mmd->new_vss_status_flags & VSS_REPOS;
550 }
551
552 /**
553 * Check if the vss is currently paused.
554 *
555 * \return Greater than zero if paused, zero otherwise.
556 *
557 */
558 unsigned int vss_paused(void)
559 {
560 return !(mmd->new_vss_status_flags & VSS_NEXT)
561 && !(mmd->new_vss_status_flags & VSS_PLAYING);
562 }
563
564 /**
565 * Check if the vss is currently stopped.
566 *
567 * \return Greater than zero if paused, zero otherwise.
568 *
569 */
570 unsigned int vss_stopped(void)
571 {
572 return (mmd->new_vss_status_flags & VSS_NEXT)
573 && !(mmd->new_vss_status_flags & VSS_PLAYING);
574 }
575
576 static int chk_barrier(const char *bname, const struct timeval *barrier,
577 struct timeval *diff, int print_log)
578 {
579 long ms;
580
581 if (tv_diff(now, barrier, diff) > 0)
582 return 1;
583 ms = tv2ms(diff);
584 if (print_log && ms)
585 PARA_DEBUG_LOG("%s barrier: %lims left\n", bname, ms);
586 return -1;
587 }
588
589 /*
590 * != NULL: timeout for next chunk
591 * NULL: nothing to do
592 */
593 static struct timeval *vss_compute_timeout(struct vss_task *vsst)
594 {
595 static struct timeval the_timeout;
596 struct timeval next_chunk;
597
598 if (vss_next() && vsst->map) {
599 /* only sleep a bit, nec*/
600 the_timeout.tv_sec = 0;
601 the_timeout.tv_usec = 100;
602 return &the_timeout;
603 }
604 if (chk_barrier("autoplay_delay", &vsst->autoplay_barrier,
605 &the_timeout, 1) < 0)
606 return &the_timeout;
607 if (chk_barrier("eof", &vsst->eof_barrier, &the_timeout, 1) < 0)
608 return &the_timeout;
609 if (chk_barrier("data send", &vsst->data_send_barrier,
610 &the_timeout, 1) < 0)
611 return &the_timeout;
612 if (!vss_playing() || !vsst->map)
613 return NULL;
614 compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
615 &mmd->stream_start, &next_chunk);
616 if (chk_barrier("chunk", &next_chunk, &the_timeout, 0) >= 0) {
617 /* chunk is due or bof */
618 the_timeout.tv_sec = 0;
619 the_timeout.tv_usec = 0;
620 return &the_timeout;
621 }
622 /* compute min of current timeout and next slice time */
623 compute_slice_timeout(&the_timeout);
624 return &the_timeout;
625 }
626
627 static void vss_eof(struct vss_task *vsst)
628 {
629
630 if (!vsst->map)
631 return;
632 if (mmd->new_vss_status_flags & VSS_NOMORE)
633 mmd->new_vss_status_flags = VSS_NEXT;
634 set_eof_barrier(vsst);
635 para_munmap(vsst->map, mmd->size);
636 vsst->map = NULL;
637 mmd->chunks_sent = 0;
638 mmd->offset = 0;
639 mmd->afd.afhi.seconds_total = 0;
640 mmd->afd.afhi.chunk_tv.tv_sec = 0;
641 mmd->afd.afhi.chunk_tv.tv_usec = 0;
642 free(mmd->afd.afhi.chunk_table);
643 mmd->afd.afhi.chunk_table = NULL;
644 free(mmd->afd.afhi.info_string);
645 mmd->afd.afhi.info_string = make_message("%s:\n%s:\n%s:\n", status_item_list[SI_AUDIO_FILE_INFO],
646 status_item_list[SI_TAGINFO1], status_item_list[SI_TAGINFO2]);
647 make_empty_status_items(mmd->afd.verbose_ls_output);
648 mmd->mtime = 0;
649 mmd->size = 0;
650 mmd->events++;
651 }
652
653 /**
654 * Get the list of all supported audio formats.
655 *
656 * \return Aa space separated list of all supported audio formats
657 * It is not allocated at runtime, i.e. there is no need to free
658 * the returned string in the caller.
659 */
660 const char *supported_audio_formats(void)
661 {
662 return SUPPORTED_AUDIO_FORMATS;
663 }
664
665 static int need_to_request_new_audio_file(struct vss_task *vsst)
666 {
667 struct timeval diff;
668
669 if (vsst->map) /* have audio file */
670 return 0;
671 if (!vss_playing()) /* don't need one */
672 return 0;
673 if (mmd->new_vss_status_flags & VSS_NOMORE)
674 return 0;
675 if (vsst->afsss == AFS_SOCKET_AFD_PENDING) /* already requested one */
676 return 0;
677 if (chk_barrier("autoplay_delay", &vsst->autoplay_barrier,
678 &diff, 1) < 0)
679 return 0;
680 return 1;
681 }
682
683 /**
684 * Compute the timeout for the main select-loop of the scheduler.
685 *
686 * \param s Pointer to the server scheduler.
687 * \param t Pointer to the vss task structure.
688 *
689 * Before the timeout is computed, the current vss status flags are evaluated
690 * and acted upon by calling appropriate functions from the lower layers.
691 * Possible actions include
692 *
693 * - request a new audio file from afs,
694 * - shutdown of all senders (stop/pause command),
695 * - reposition the stream (ff/jmp command).
696 */
697 static void vss_pre_select(struct sched *s, struct task *t)
698 {
699 int i;
700 struct timeval *tv, diff;
701 struct vss_task *vsst = container_of(t, struct vss_task, task);
702
703 if (!vsst->map || vss_next() || vss_paused() || vss_repos()) {
704 struct fec_client *fc, *tmp;
705 for (i = 0; senders[i].name; i++)
706 if (senders[i].shutdown_clients)
707 senders[i].shutdown_clients();
708 list_for_each_entry_safe(fc, tmp, &fec_client_list, node) {
709 fc->first_stream_chunk = -1;
710 fc->error = 0;
711 }
712 mmd->stream_start.tv_sec = 0;
713 mmd->stream_start.tv_usec = 0;
714 }
715 if (vss_next())
716 vss_eof(vsst);
717 else if (vss_paused()) {
718 if (mmd->chunks_sent)
719 set_eof_barrier(vsst);
720 mmd->chunks_sent = 0;
721 } else if (vss_repos()) {
722 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
723 set_eof_barrier(vsst);
724 mmd->chunks_sent = 0;
725 mmd->current_chunk = mmd->repos_request;
726 mmd->new_vss_status_flags &= ~VSS_REPOS;
727 }
728 if (need_to_request_new_audio_file(vsst)) {
729 PARA_DEBUG_LOG("ready and playing, but no audio file\n");
730 para_fd_set(vsst->afs_socket, &s->wfds, &s->max_fileno);
731 vsst->afsss = AFS_SOCKET_CHECK_FOR_WRITE;
732 } else
733 para_fd_set(vsst->afs_socket, &s->rfds, &s->max_fileno);
734 for (i = 0; senders[i].name; i++) {
735 if (!senders[i].pre_select)
736 continue;
737 senders[i].pre_select(&s->max_fileno, &s->rfds, &s->wfds);
738 }
739 tv = vss_compute_timeout(vsst);
740 if (tv && tv_diff(tv, &s->timeout, &diff) < 0)
741 s->timeout = *tv;
742 }
743
744 static int recv_afs_msg(int afs_socket, int *fd, uint32_t *code, uint32_t *data)
745 {
746 char control[255], buf[8];
747 struct msghdr msg = {.msg_iov = NULL};
748 struct cmsghdr *cmsg;
749 struct iovec iov;
750 int ret = 0;
751
752 *fd = -1;
753 iov.iov_base = buf;
754 iov.iov_len = sizeof(buf);
755 msg.msg_iov = &iov;
756 msg.msg_iovlen = 1;
757 msg.msg_control = control;
758 msg.msg_controllen = sizeof(control);
759 memset(buf, 0, sizeof(buf));
760 ret = recvmsg(afs_socket, &msg, 0);
761 if (ret < 0)
762 return -ERRNO_TO_PARA_ERROR(errno);
763 if (iov.iov_len != sizeof(buf))
764 return -E_AFS_SHORT_READ;
765 *code = *(uint32_t*)buf;
766 *data = *(uint32_t*)(buf + 4);
767 for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
768 if (cmsg->cmsg_level != SOL_SOCKET
769 || cmsg->cmsg_type != SCM_RIGHTS)
770 continue;
771 if ((cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int) != 1)
772 continue;
773 *fd = *(int *)CMSG_DATA(cmsg);
774 }
775 return 1;
776 }
777
778 static void recv_afs_result(struct vss_task *vsst)
779 {
780 int ret, passed_fd, shmid;
781 uint32_t afs_code = 0, afs_data = 0;
782 struct stat statbuf;
783
784 vsst->afsss = AFS_SOCKET_READY;
785 ret = recv_afs_msg(vsst->afs_socket, &passed_fd, &afs_code, &afs_data);
786 if (ret < 0)
787 goto err;
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 free(mmd->afd.afhi.info_string);
797 ret = load_afd(shmid, &mmd->afd);
798 if (ret < 0)
799 goto err;
800 shm_destroy(shmid);
801 ret = fstat(passed_fd, &statbuf);
802 if (ret < 0) {
803 PARA_ERROR_LOG("fstat error:\n");
804 ret = -ERRNO_TO_PARA_ERROR(errno);
805 goto err;
806 }
807 mmd->size = statbuf.st_size;
808 mmd->mtime = statbuf.st_mtime;
809 ret = para_mmap(mmd->size, PROT_READ, MAP_PRIVATE, passed_fd,
810 0, &vsst->map);
811 if (ret < 0)
812 goto err;
813 close(passed_fd);
814 mmd->chunks_sent = 0;
815 mmd->current_chunk = 0;
816 mmd->offset = 0;
817 mmd->events++;
818 mmd->num_played++;
819 mmd->new_vss_status_flags &= (~VSS_NEXT);
820 afh_get_header(&mmd->afd.afhi, vsst->map, &vsst->header_buf,
821 &vsst->header_len);
822 return;
823 err:
824 free(mmd->afd.afhi.chunk_table);
825 if (passed_fd >= 0)
826 close(passed_fd);
827 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
828 mmd->new_vss_status_flags = VSS_NEXT;
829 }
830
831 /**
832 * Main sending function.
833 *
834 * This function gets called from vss_post_select(). It checks whether the next
835 * chunk of data should be pushed out. It obtains a pointer to the data to be
836 * sent out as well as its length from mmd->afd.afhi. This information is then
837 * passed to each supported sender's send() function as well as to the send()
838 * functions of each registered fec client.
839 */
840 static void vss_send(struct vss_task *vsst)
841 {
842 int i, fec_active = 0;
843 struct timeval due;
844 struct fec_client *fc, *tmp_fc;
845
846 if (!vsst->map || !vss_playing())
847 return;
848 if (chk_barrier("eof", &vsst->eof_barrier, &due, 1) < 0)
849 return;
850 if (chk_barrier("data send", &vsst->data_send_barrier,
851 &due, 1) < 0)
852 return;
853 list_for_each_entry_safe(fc, tmp_fc, &fec_client_list, node) {
854 if (fc->error < 0)
855 continue;
856 if (!next_slice_is_due(fc, NULL)) {
857 fec_active = 1;
858 continue;
859 }
860 if (compute_next_fec_slice(fc, vsst) <= 0)
861 continue;
862 PARA_DEBUG_LOG("sending %d:%d (%u bytes)\n", fc->group.num,
863 fc->current_slice_num, fc->fcp->max_slice_bytes);
864 fc->fcp->send((char *)fc->enc_buf,
865 fc->fcp->max_slice_bytes,
866 fc->fcp->private_data);
867 fc->current_slice_num++;
868 fec_active = 1;
869 }
870 if (mmd->current_chunk >= mmd->afd.afhi.chunks_total) { /* eof */
871 if (!fec_active)
872 mmd->new_vss_status_flags |= VSS_NEXT;
873 return;
874 }
875 compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
876 &mmd->stream_start, &due);
877 if (tv_diff(&due, now, NULL) <= 0) {
878 const char *buf;
879 size_t len;
880
881 if (!mmd->chunks_sent) {
882 struct timeval tmp;
883 mmd->stream_start = *now;
884 tv_scale(mmd->current_chunk, &mmd->afd.afhi.chunk_tv, &tmp);
885 mmd->offset = tv2ms(&tmp);
886 mmd->events++;
887 }
888 /*
889 * We call the send function also in case of empty chunks as
890 * they might have still some data queued which can be sent in
891 * this case.
892 */
893 afh_get_chunk(mmd->current_chunk, &mmd->afd.afhi, vsst->map,
894 &buf, &len);
895 for (i = 0; senders[i].name; i++) {
896 if (!senders[i].send)
897 continue;
898 senders[i].send(mmd->current_chunk, mmd->chunks_sent,
899 buf, len, vsst->header_buf, vsst->header_len);
900 }
901 mmd->chunks_sent++;
902 mmd->current_chunk++;
903 }
904 }
905
906 static void vss_post_select(struct sched *s, struct task *t)
907 {
908 int ret, i;
909 struct vss_task *vsst = container_of(t, struct vss_task, task);
910
911
912 if (mmd->sender_cmd_data.cmd_num >= 0) {
913 int num = mmd->sender_cmd_data.cmd_num,
914 sender_num = mmd->sender_cmd_data.sender_num;
915
916 if (senders[sender_num].client_cmds[num])
917 senders[sender_num].client_cmds[num](&mmd->sender_cmd_data);
918 mmd->sender_cmd_data.cmd_num = -1;
919 }
920 if (vsst->afsss != AFS_SOCKET_CHECK_FOR_WRITE) {
921 if (FD_ISSET(vsst->afs_socket, &s->rfds))
922 recv_afs_result(vsst);
923 } else if (FD_ISSET(vsst->afs_socket, &s->wfds)) {
924 PARA_NOTICE_LOG("requesting new fd from afs\n");
925 ret = send_buffer(vsst->afs_socket, "new");
926 if (ret < 0)
927 PARA_CRIT_LOG("%s\n", para_strerror(-ret));
928 else
929 vsst->afsss = AFS_SOCKET_AFD_PENDING;
930 }
931 for (i = 0; senders[i].name; i++) {
932 if (!senders[i].post_select)
933 continue;
934 senders[i].post_select(&s->rfds, &s->wfds);
935 }
936 if ((vss_playing() && !(mmd->vss_status_flags & VSS_PLAYING)) ||
937 (vss_next() && vss_playing()))
938 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
939 vss_send(vsst);
940 }
941
942 /**
943 * Initialize the virtual streaming system task.
944 *
945 * \param afs_socket The fd for communication with afs.
946 *
947 * This also initializes all supported senders and starts streaming
948 * if the --autoplay command line flag was given.
949 */
950 void init_vss_task(int afs_socket)
951 {
952 static struct vss_task vss_task_struct, *vsst = &vss_task_struct;
953 int i;
954 char *hn = para_hostname(), *home = para_homedir();
955 long unsigned announce_time = conf.announce_time_arg > 0?
956 conf.announce_time_arg : 300,
957 autoplay_delay = conf.autoplay_delay_arg > 0?
958 conf.autoplay_delay_arg : 0;
959 vsst->header_interval.tv_sec = 5; /* should this be configurable? */
960 vsst->afs_socket = afs_socket;
961 vsst->task.pre_select = vss_pre_select;
962 vsst->task.post_select = vss_post_select;
963 ms2tv(announce_time, &vsst->announce_tv);
964 PARA_INFO_LOG("announce timeval: %lums\n", tv2ms(&vsst->announce_tv));
965 INIT_LIST_HEAD(&fec_client_list);
966 for (i = 0; senders[i].name; i++) {
967 PARA_NOTICE_LOG("initializing %s sender\n", senders[i].name);
968 senders[i].init(&senders[i]);
969 }
970 free(hn);
971 free(home);
972 mmd->sender_cmd_data.cmd_num = -1;
973 make_empty_status_items(mmd->afd.verbose_ls_output);
974 if (conf.autoplay_given) {
975 struct timeval tmp;
976 mmd->vss_status_flags |= VSS_PLAYING;
977 mmd->new_vss_status_flags |= VSS_PLAYING;
978 ms2tv(autoplay_delay, &tmp);
979 tv_add(now, &tmp, &vsst->autoplay_barrier);
980 tv_add(&vsst->autoplay_barrier, &vsst->announce_tv,
981 &vsst->data_send_barrier);
982 }
983 register_task(&vsst->task);
984 }