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