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