vss: Take fec group durations into account when computing the eof barrier.
[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 unsigned num_header_slices;
128 };
129
130 /**
131 * Describes one connected FEC client.
132 */
133 struct fec_client {
134 /** Parameters requested by the client. */
135 struct fec_client_parms *fcp;
136 /** Used by the core FEC code. */
137 struct fec_parms *parms;
138 /** The position of this client in the fec client list. */
139 struct list_head node;
140 /** When the first slice for this client was sent. */
141 struct timeval stream_start;
142 /** The first chunk sent to this FEC client. */
143 int first_stream_chunk;
144 /** Describes the current group. */
145 struct fec_group group;
146 /** The current slice. */
147 uint8_t current_slice_num;
148 /** The data to be FEC-encoded (point to a region within the mapped audio file). */
149 const unsigned char **src_data;
150 /** Last time an audio header was sent. */
151 struct timeval next_header_time;
152 /** Used for the last source pointer of an audio file. */
153 unsigned char *extra_src_buf;
154 /** Extra slices needed to store largest chunk + header. */
155 int num_extra_slices;
156 /** Contains the FEC-encoded data. */
157 unsigned char *enc_buf;
158 };
159
160 /**
161 * Get the chunk time of the current audio file.
162 *
163 * \return A pointer to a struct containing the chunk time, or NULL,
164 * if currently no audio file is selected.
165 */
166 struct timeval *vss_chunk_time(void)
167 {
168 if (mmd->afd.afhi.chunk_tv.tv_sec == 0 &&
169 mmd->afd.afhi.chunk_tv.tv_usec == 0)
170 return NULL;
171 return &mmd->afd.afhi.chunk_tv;
172 }
173
174 /**
175 * Write a fec header to a buffer.
176 *
177 * \param buf The buffer to write to.
178 * \param h The fec header to write.
179 */
180 static void write_fec_header(struct fec_client *fc, struct vss_task *vsst)
181 {
182 char *buf = (char *)fc->enc_buf;
183 struct fec_group *g = &fc->group;
184 struct fec_client_parms *p = fc->fcp;
185
186 write_u32(buf, FEC_MAGIC);
187
188 write_u8(buf + 4, p->slices_per_group + fc->num_extra_slices);
189 write_u8(buf + 5, p->data_slices_per_group + fc->num_extra_slices);
190 write_u32(buf + 6, g->num_header_slices? vsst->header_len : 0);
191
192 write_u32(buf + 10, g->num);
193 write_u32(buf + 14, g->bytes);
194
195 write_u8(buf + 18, fc->current_slice_num);
196 write_u16(buf + 20, p->max_slice_bytes - FEC_HEADER_SIZE);
197 write_u8(buf + 22, g->first_chunk? 0 : 1);
198 write_u8(buf + 23, vsst->header_len? 1 : 0);
199 memset(buf + 24, 0, 7);
200 }
201
202 static int need_audio_header(struct fec_client *fc, struct vss_task *vsst)
203 {
204 if (!mmd->current_chunk) {
205 tv_add(now, &vsst->header_interval, &fc->next_header_time);
206 return 0;
207 }
208 if (!vsst->header_buf)
209 return 0;
210 if (!vsst->header_len)
211 return 0;
212 if (fc->group.num && tv_diff(&fc->next_header_time, now, NULL) > 0)
213 return 0;
214 tv_add(now, &vsst->header_interval, &fc->next_header_time);
215 return 1;
216 }
217
218 static uint8_t num_slices(long unsigned bytes, struct fec_client *fc)
219 {
220 uint16_t m = fc->fcp->max_slice_bytes - FEC_HEADER_SIZE;
221 return (bytes + m - 1) / m;
222 }
223
224 static int setup_next_fec_group(struct fec_client *fc, struct vss_task *vsst)
225 {
226 int i, k, data_slices;
227 size_t len;
228 const char *buf, *start_buf;
229 struct timeval tmp, *chunk_tv = vss_chunk_time();
230 struct fec_group *g = &fc->group;
231 unsigned slice_bytes = fc->fcp->max_slice_bytes - FEC_HEADER_SIZE;
232 uint32_t max_data_size;
233
234 assert(chunk_tv);
235 k = fc->fcp->data_slices_per_group + fc->num_extra_slices;
236 if (fc->first_stream_chunk < 0) {
237 uint32_t largest = afh_get_largest_chunk_size(&mmd->afd.afhi)
238 + vsst->header_len;
239 uint8_t needed = num_slices(largest, fc), want;
240 if (needed > fc->fcp->data_slices_per_group)
241 PARA_WARNING_LOG("fec parms insufficient for this audio file\n");
242 want = PARA_MAX(needed, fc->fcp->data_slices_per_group);
243 if (want != k) {
244 int ret;
245 fec_free(fc->parms);
246 fc->src_data = para_realloc(fc->src_data, want * sizeof(char *));
247 ret = fec_new(want, want + fc->fcp->slices_per_group
248 - fc->fcp->data_slices_per_group, &fc->parms);
249 if (ret < 0)
250 return ret;
251 k = want;
252 fc->num_extra_slices = 0;
253 if (k > fc->fcp->data_slices_per_group) {
254 fc->num_extra_slices = k - fc->fcp->data_slices_per_group;
255 PARA_NOTICE_LOG("using %d extra slices\n",
256 fc->num_extra_slices);
257 }
258 }
259 fc->stream_start = *now;
260 fc->first_stream_chunk = mmd->current_chunk;
261 g->first_chunk = mmd->current_chunk;
262 g->num = 0;
263 } else {
264 g->first_chunk += g->num_chunks;
265 g->num++;
266 }
267 if (g->first_chunk >= mmd->afd.afhi.chunks_total)
268 return 0;
269 if (need_audio_header(fc, vsst))
270 g->num_header_slices = num_slices(vsst->header_len, fc);
271 else
272 g->num_header_slices = 0;
273 afh_get_chunk(g->first_chunk, &mmd->afd.afhi, vsst->map, &start_buf,
274 &len);
275 data_slices = k - g->num_header_slices;
276 assert(data_slices);
277 max_data_size = slice_bytes * data_slices;
278 g->bytes = 0;
279 for (i = g->first_chunk; i < mmd->afd.afhi.chunks_total; i++) {
280 afh_get_chunk(i, &mmd->afd.afhi, vsst->map, &buf, &len);
281 if (g->bytes + len > max_data_size)
282 break;
283 g->bytes += len;
284 }
285 g->num_chunks = i - g->first_chunk;
286 assert(g->num_chunks);
287 fc->current_slice_num = 0;
288
289 /* setup header slices */
290 buf = vsst->header_buf;
291 for (i = 0; i < g->num_header_slices; i++) {
292 fc->src_data[i] = (const unsigned char *)buf;
293 buf += slice_bytes;
294 }
295
296 /* setup data slices */
297 buf = start_buf;
298 for (i = g->num_header_slices; i < k; i++) {
299 if (buf + slice_bytes > vsst->map + mmd->size)
300 /*
301 * Can not use the memory mapped audio file for this
302 * slice as it goes beyond the map. This slice will not
303 * be fully used.
304 */
305 break;
306 fc->src_data[i] = (const unsigned char *)buf;
307 buf += slice_bytes;
308 }
309 if (i < k) {
310 uint32_t payload_size = vsst->map + mmd->size - buf;
311 memcpy(fc->extra_src_buf, buf, payload_size);
312 fc->src_data[i] = fc->extra_src_buf;
313 i++;
314 /* use arbitrary data for all remaining slices */
315 buf = vsst->map;
316 for (; i < k; i++)
317 fc->src_data[i] = (const unsigned char *)buf;
318 }
319
320 /* setup group timing */
321 tv_scale(g->first_chunk - fc->first_stream_chunk, chunk_tv, &tmp);
322 tv_add(&fc->stream_start, &tmp, &g->start);
323 if (g->num) /* quick hack to avoid buffer underruns */
324 g->start.tv_sec--;
325 tv_scale(g->num_chunks, chunk_tv, &tmp); /* group duration */
326 tv_divide(fc->fcp->slices_per_group + fc->num_extra_slices,
327 &tmp, &g->slice_duration);
328
329 PARA_DEBUG_LOG("FEC group %d: %d chunks (%d - %d), %d header slices, %d data slices\n",
330 g->num, g->num_chunks, g->first_chunk,
331 g->first_chunk + g->num_chunks - 1,
332 g->num_header_slices, data_slices
333 );
334 PARA_DEBUG_LOG("durations (group/chunk/slice): %lu/%lu/%lu\n",
335 tv2ms(&tmp), tv2ms(chunk_tv), tv2ms(&g->slice_duration));
336 return 1;
337 }
338
339 static int compute_next_fec_slice(struct fec_client *fc, struct vss_task *vsst)
340 {
341 if (fc->first_stream_chunk < 0 || fc->current_slice_num
342 == fc->fcp->slices_per_group + fc->num_extra_slices) {
343 int ret = setup_next_fec_group(fc, vsst);
344 if (ret <= 0)
345 return ret;
346 }
347 write_fec_header(fc, vsst);
348 fec_encode(fc->parms, fc->src_data, fc->enc_buf + FEC_HEADER_SIZE,
349 fc->current_slice_num,
350 fc->fcp->max_slice_bytes - FEC_HEADER_SIZE);
351 return 1;
352 }
353
354 /**
355 * Return a buffer that marks the end of the stream.
356 *
357 * \param buf Result pointer.
358 * \return The length of the eof buffer.
359 *
360 * This is used for (multicast) udp streaming where closing the socket on the
361 * sender might not give rise to an eof condition at the peer.
362 */
363 size_t vss_get_fec_eof_packet(const char **buf)
364 {
365 static const char fec_eof_packet[FEC_HEADER_SIZE] = FEC_EOF_PACKET;
366 *buf = fec_eof_packet;
367 return FEC_HEADER_SIZE;
368 }
369
370 /**
371 * Add one entry to the list of active fec clients.
372 *
373 * \param fcp Describes the fec parameters to be used for this client.
374 * \param result An opaque pointer that must be used by remove the client later.
375 *
376 * \return Standard.
377 */
378 int vss_add_fec_client(struct fec_client_parms *fcp, struct fec_client **result)
379 {
380 int ret;
381 struct fec_client *fc;
382
383 if (fcp->max_slice_bytes < FEC_HEADER_SIZE + fcp->data_slices_per_group)
384 return -ERRNO_TO_PARA_ERROR(EINVAL);
385 fc = para_calloc(sizeof(*fc));
386 fc->fcp = fcp;
387 ret = fec_new(fcp->data_slices_per_group, fcp->slices_per_group,
388 &fc->parms);
389 if (ret < 0)
390 goto err;
391 fc->first_stream_chunk = -1; /* stream not yet started */
392 fc->src_data = para_malloc(fc->fcp->slices_per_group * sizeof(char *));
393 fc->enc_buf = para_calloc(fc->fcp->max_slice_bytes);
394 fc->num_extra_slices = 0;
395 fc->extra_src_buf = para_calloc(fc->fcp->max_slice_bytes);
396 fc->next_header_time.tv_sec = 0;
397 para_list_add(&fc->node, &fec_client_list);
398 *result = fc;
399 return 1;
400 err:
401 fec_free(fc->parms);
402 free(fc);
403 *result = NULL;
404 return ret;
405 }
406
407 /**
408 * Remove one entry from the list of active fec clients.
409 *
410 * \param fc The client to be removed.
411 */
412 void vss_del_fec_client(struct fec_client *fc)
413 {
414 list_del(&fc->node);
415 free(fc->src_data);
416 free(fc->enc_buf);
417 free(fc->extra_src_buf);
418 fec_free(fc->parms);
419 free(fc);
420 }
421
422 /*
423 * Compute if/when next slice is due. If it isn't due yet and \a diff is
424 * not \p Null, compute the time difference next - now, where
425 *
426 * next = stream_start + (first_group_chunk - first_stream_chunk)
427 * * chunk_time + slice_num * slice_time
428 */
429 static int next_slice_is_due(struct fec_client *fc, struct timeval *diff)
430 {
431 struct timeval tmp, next;
432 int ret;
433
434 if (fc->first_stream_chunk < 0)
435 return 1;
436 tv_scale(fc->current_slice_num, &fc->group.slice_duration, &tmp);
437 tv_add(&tmp, &fc->group.start, &next);
438 ret = tv_diff(&next, now, diff);
439 return ret < 0? 1 : 0;
440 }
441
442 static void compute_slice_timeout(struct timeval *timeout)
443 {
444 struct fec_client *fc;
445
446 assert(vss_playing());
447 list_for_each_entry(fc, &fec_client_list, node) {
448 struct timeval diff;
449
450 if (next_slice_is_due(fc, &diff)) {
451 timeout->tv_sec = 0;
452 timeout->tv_usec = 0;
453 return;
454 }
455 /* timeout = min(timeout, diff) */
456 if (tv_diff(&diff, timeout, NULL) < 0)
457 *timeout = diff;
458 }
459 }
460
461 static void set_eof_barrier(struct vss_task *vsst)
462 {
463 struct fec_client *fc;
464 struct timeval timeout = mmd->afd.afhi.eof_tv,
465 *chunk_tv = vss_chunk_time();
466
467 if (!chunk_tv)
468 goto out;
469 list_for_each_entry(fc, &fec_client_list, node) {
470 struct timeval group_duration;
471 tv_scale(fc->group.num_chunks, chunk_tv, &group_duration);
472 if (tv_diff(&timeout, &group_duration, NULL) < 0)
473 timeout = group_duration;
474 }
475 out:
476 tv_add(now, &timeout, &vsst->eof_barrier);
477 }
478
479 /**
480 * Check if vss status flag \a P (playing) is set.
481 *
482 * \return Greater than zero if playing, zero otherwise.
483 *
484 */
485 unsigned int vss_playing(void)
486 {
487 return mmd->new_vss_status_flags & VSS_PLAYING;
488 }
489
490 /**
491 * Check if the \a N (next) status flag is set.
492 *
493 * \return Greater than zero if set, zero if not.
494 *
495 */
496 unsigned int vss_next(void)
497 {
498 return mmd->new_vss_status_flags & VSS_NEXT;
499 }
500
501 /**
502 * Check if a reposition request is pending.
503 *
504 * \return Greater than zero if true, zero otherwise.
505 *
506 */
507 unsigned int vss_repos(void)
508 {
509 return mmd->new_vss_status_flags & VSS_REPOS;
510 }
511
512 /**
513 * Check if the vss is currently paused.
514 *
515 * \return Greater than zero if paused, zero otherwise.
516 *
517 */
518 unsigned int vss_paused(void)
519 {
520 return !(mmd->new_vss_status_flags & VSS_NEXT)
521 && !(mmd->new_vss_status_flags & VSS_PLAYING);
522 }
523
524 /**
525 * Check if the vss is currently stopped.
526 *
527 * \return Greater than zero if paused, zero otherwise.
528 *
529 */
530 unsigned int vss_stopped(void)
531 {
532 return (mmd->new_vss_status_flags & VSS_NEXT)
533 && !(mmd->new_vss_status_flags & VSS_PLAYING);
534 }
535
536 static int chk_barrier(const char *bname, const struct timeval *barrier,
537 struct timeval *diff, int print_log)
538 {
539 long ms;
540
541 if (tv_diff(now, barrier, diff) > 0)
542 return 1;
543 ms = tv2ms(diff);
544 if (print_log && ms)
545 PARA_DEBUG_LOG("%s barrier: %lims left\n", bname, ms);
546 return -1;
547 }
548
549 /*
550 * != NULL: timeout for next chunk
551 * NULL: nothing to do
552 */
553 static struct timeval *vss_compute_timeout(struct vss_task *vsst)
554 {
555 static struct timeval the_timeout;
556 struct timeval next_chunk;
557
558 if (vss_next() && vsst->map) {
559 /* only sleep a bit, nec*/
560 the_timeout.tv_sec = 0;
561 the_timeout.tv_usec = 100;
562 return &the_timeout;
563 }
564 if (chk_barrier("autoplay_delay", &vsst->autoplay_barrier,
565 &the_timeout, 1) < 0)
566 return &the_timeout;
567 if (chk_barrier("eof", &vsst->eof_barrier, &the_timeout, 1) < 0)
568 return &the_timeout;
569 if (chk_barrier("data send", &vsst->data_send_barrier,
570 &the_timeout, 1) < 0)
571 return &the_timeout;
572 if (!vss_playing() || !vsst->map)
573 return NULL;
574 compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
575 &mmd->stream_start, &next_chunk);
576 if (chk_barrier("chunk", &next_chunk, &the_timeout, 0) >= 0) {
577 /* chunk is due or bof */
578 the_timeout.tv_sec = 0;
579 the_timeout.tv_usec = 0;
580 return &the_timeout;
581 }
582 /* compute min of current timeout and next slice time */
583 compute_slice_timeout(&the_timeout);
584 return &the_timeout;
585 }
586
587 static void vss_eof(struct vss_task *vsst)
588 {
589
590 mmd->stream_start = *now;
591 if (!vsst->map)
592 return;
593 if (mmd->new_vss_status_flags & VSS_NOMORE)
594 mmd->new_vss_status_flags = VSS_NEXT;
595 set_eof_barrier(vsst);
596 para_munmap(vsst->map, mmd->size);
597 vsst->map = NULL;
598 mmd->chunks_sent = 0;
599 mmd->offset = 0;
600 mmd->afd.afhi.seconds_total = 0;
601 mmd->afd.afhi.chunk_tv.tv_sec = 0;
602 mmd->afd.afhi.chunk_tv.tv_usec = 0;
603 free(mmd->afd.afhi.chunk_table);
604 mmd->afd.afhi.chunk_table = NULL;
605 free(mmd->afd.afhi.info_string);
606 mmd->afd.afhi.info_string = make_message("%s:\n%s:\n%s:\n", status_item_list[SI_AUDIO_FILE_INFO],
607 status_item_list[SI_TAGINFO1], status_item_list[SI_TAGINFO2]);
608 make_empty_status_items(mmd->afd.verbose_ls_output);
609 mmd->mtime = 0;
610 mmd->size = 0;
611 mmd->events++;
612 }
613
614 /**
615 * Get the list of all supported audio formats.
616 *
617 * \return Aa space separated list of all supported audio formats
618 * It is not allocated at runtime, i.e. there is no need to free
619 * the returned string in the caller.
620 */
621 const char *supported_audio_formats(void)
622 {
623 return SUPPORTED_AUDIO_FORMATS;
624 }
625
626 static int need_to_request_new_audio_file(struct vss_task *vsst)
627 {
628 struct timeval diff;
629
630 if (vsst->map) /* have audio file */
631 return 0;
632 if (!vss_playing()) /* don't need one */
633 return 0;
634 if (mmd->new_vss_status_flags & VSS_NOMORE)
635 return 0;
636 if (vsst->afsss == AFS_SOCKET_AFD_PENDING) /* already requested one */
637 return 0;
638 if (chk_barrier("autoplay_delay", &vsst->autoplay_barrier,
639 &diff, 1) < 0)
640 return 0;
641 return 1;
642 }
643
644 /**
645 * Compute the timeout for para_server's main select-loop.
646 *
647 * This function gets called from para_server to determine the timeout value
648 * for its main select loop.
649 *
650 * \param s Pointer to the server scheduler.
651 * \param t Pointer to the vss task structure.
652 *
653 * Before the timeout is computed, the current vss status flags are evaluated
654 * and acted upon by calling appropriate functions from the lower layers.
655 * Possible actions include
656 *
657 * - request a new audio file from afs,
658 * - shutdown of all senders (stop/pause command),
659 * - reposition the stream (ff/jmp command).
660 */
661 static void vss_pre_select(struct sched *s, struct task *t)
662 {
663 int i;
664 struct timeval *tv, diff;
665 struct vss_task *vsst = container_of(t, struct vss_task, task);
666
667 if (!vsst->map || vss_next() || vss_paused() || vss_repos()) {
668 struct fec_client *fc, *tmp;
669 for (i = 0; senders[i].name; i++)
670 if (senders[i].shutdown_clients)
671 senders[i].shutdown_clients();
672 list_for_each_entry_safe(fc, tmp, &fec_client_list, node)
673 fc->first_stream_chunk = -1;
674 }
675 if (vss_next())
676 vss_eof(vsst);
677 else if (vss_paused()) {
678 if (mmd->chunks_sent)
679 set_eof_barrier(vsst);
680 mmd->chunks_sent = 0;
681 } else if (vss_repos()) {
682 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
683 set_eof_barrier(vsst);
684 mmd->chunks_sent = 0;
685 mmd->current_chunk = mmd->repos_request;
686 mmd->new_vss_status_flags &= ~VSS_REPOS;
687 }
688 if (need_to_request_new_audio_file(vsst)) {
689 PARA_DEBUG_LOG("ready and playing, but no audio file\n");
690 para_fd_set(vsst->afs_socket, &s->wfds, &s->max_fileno);
691 vsst->afsss = AFS_SOCKET_CHECK_FOR_WRITE;
692 } else
693 para_fd_set(vsst->afs_socket, &s->rfds, &s->max_fileno);
694 for (i = 0; senders[i].name; i++) {
695 if (!senders[i].pre_select)
696 continue;
697 senders[i].pre_select(&s->max_fileno, &s->rfds, &s->wfds);
698 }
699 tv = vss_compute_timeout(vsst);
700 if (tv && tv_diff(tv, &s->timeout, &diff) < 0)
701 s->timeout = *tv;
702 }
703
704 static int recv_afs_msg(int afs_socket, int *fd, uint32_t *code, uint32_t *data)
705 {
706 char control[255], buf[8];
707 struct msghdr msg = {.msg_iov = NULL};
708 struct cmsghdr *cmsg;
709 struct iovec iov;
710 int ret = 0;
711
712 *fd = -1;
713 iov.iov_base = buf;
714 iov.iov_len = sizeof(buf);
715 msg.msg_iov = &iov;
716 msg.msg_iovlen = 1;
717 msg.msg_control = control;
718 msg.msg_controllen = sizeof(control);
719 memset(buf, 0, sizeof(buf));
720 ret = recvmsg(afs_socket, &msg, 0);
721 if (ret < 0)
722 return -ERRNO_TO_PARA_ERROR(errno);
723 if (iov.iov_len != sizeof(buf))
724 return -E_AFS_SHORT_READ;
725 *code = *(uint32_t*)buf;
726 *data = *(uint32_t*)(buf + 4);
727 for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
728 if (cmsg->cmsg_level != SOL_SOCKET
729 || cmsg->cmsg_type != SCM_RIGHTS)
730 continue;
731 if ((cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int) != 1)
732 continue;
733 *fd = *(int *)CMSG_DATA(cmsg);
734 }
735 return 1;
736 }
737
738 static void recv_afs_result(struct vss_task *vsst)
739 {
740 int ret, passed_fd, shmid;
741 uint32_t afs_code = 0, afs_data = 0;
742 struct stat statbuf;
743
744 vsst->afsss = AFS_SOCKET_READY;
745 mmd->afd.afhi.chunk_table = NULL;
746 ret = recv_afs_msg(vsst->afs_socket, &passed_fd, &afs_code, &afs_data);
747 if (ret < 0)
748 goto err;
749 PARA_DEBUG_LOG("fd: %d, code: %u, shmid: %u\n", passed_fd, afs_code,
750 afs_data);
751 ret = -E_NOFD;
752 if (afs_code != NEXT_AUDIO_FILE)
753 goto err;
754 if (passed_fd < 0)
755 goto err;
756 shmid = afs_data;
757 ret = load_afd(shmid, &mmd->afd);
758 if (ret < 0)
759 goto err;
760 shm_destroy(shmid);
761 ret = fstat(passed_fd, &statbuf);
762 if (ret < 0) {
763 PARA_ERROR_LOG("fstat error:\n");
764 ret = -ERRNO_TO_PARA_ERROR(errno);
765 goto err;
766 }
767 mmd->size = statbuf.st_size;
768 mmd->mtime = statbuf.st_mtime;
769 ret = para_mmap(mmd->size, PROT_READ, MAP_PRIVATE, passed_fd,
770 0, &vsst->map);
771 if (ret < 0)
772 goto err;
773 close(passed_fd);
774 mmd->chunks_sent = 0;
775 mmd->current_chunk = 0;
776 mmd->offset = 0;
777 mmd->events++;
778 mmd->num_played++;
779 mmd->new_vss_status_flags &= (~VSS_NEXT);
780 afh_get_header(&mmd->afd.afhi, vsst->map, &vsst->header_buf,
781 &vsst->header_len);
782 return;
783 err:
784 free(mmd->afd.afhi.chunk_table);
785 if (passed_fd >= 0)
786 close(passed_fd);
787 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
788 mmd->new_vss_status_flags = VSS_NEXT;
789 }
790
791 /**
792 * Main sending function.
793 *
794 * This function gets called from vss_post_select(). It checks whether the next
795 * chunk of data should be pushed out. It obtains a pointer to the data to be
796 * sent out as well as its length from mmd->afd.afhi. This information is then
797 * passed to each supported sender's send() function as well as to the send()
798 * functions of each registered fec client.
799 */
800 static void vss_send(struct vss_task *vsst)
801 {
802 int i, sent_something = 0;
803 struct timeval due;
804 struct fec_client *fc, *tmp_fc;
805
806 if (!vsst->map || !vss_playing())
807 return;
808 if (chk_barrier("eof", &vsst->eof_barrier, &due, 1) < 0)
809 return;
810 if (chk_barrier("data send", &vsst->data_send_barrier,
811 &due, 1) < 0)
812 return;
813 list_for_each_entry_safe(fc, tmp_fc, &fec_client_list, node) {
814 if (!next_slice_is_due(fc, NULL))
815 continue;
816 if (compute_next_fec_slice(fc, vsst) <= 0)
817 continue;
818 PARA_DEBUG_LOG("sending %d:%d (%u bytes)\n", fc->group.num,
819 fc->current_slice_num, fc->fcp->max_slice_bytes);
820 fc->fcp->send((char *)fc->enc_buf,
821 fc->fcp->max_slice_bytes,
822 fc->fcp->private_data);
823 fc->current_slice_num++;
824 sent_something = 1;
825 }
826 if (mmd->current_chunk >= mmd->afd.afhi.chunks_total) { /* eof */
827 if (!sent_something)
828 mmd->new_vss_status_flags |= VSS_NEXT;
829 return;
830 }
831 compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
832 &mmd->stream_start, &due);
833 if (tv_diff(&due, now, NULL) <= 0) {
834 const char *buf;
835 size_t len;
836
837 if (!mmd->chunks_sent) {
838 struct timeval tmp;
839 mmd->stream_start = *now;
840 tv_scale(mmd->current_chunk, &mmd->afd.afhi.chunk_tv, &tmp);
841 mmd->offset = tv2ms(&tmp);
842 mmd->events++;
843 }
844 /*
845 * We call the send function also in case of empty chunks as
846 * they might have still some data queued which can be sent in
847 * this case.
848 */
849 afh_get_chunk(mmd->current_chunk, &mmd->afd.afhi, vsst->map,
850 &buf, &len);
851 for (i = 0; senders[i].name; i++) {
852 if (!senders[i].send)
853 continue;
854 senders[i].send(mmd->current_chunk, mmd->chunks_sent,
855 buf, len, vsst->header_buf, vsst->header_len);
856 }
857 mmd->chunks_sent++;
858 mmd->current_chunk++;
859 }
860 }
861
862 static void vss_post_select(struct sched *s, struct task *t)
863 {
864 int ret, i;
865 struct vss_task *vsst = container_of(t, struct vss_task, task);
866
867
868 if (mmd->sender_cmd_data.cmd_num >= 0) {
869 int num = mmd->sender_cmd_data.cmd_num,
870 sender_num = mmd->sender_cmd_data.sender_num;
871
872 if (senders[sender_num].client_cmds[num])
873 senders[sender_num].client_cmds[num](&mmd->sender_cmd_data);
874 mmd->sender_cmd_data.cmd_num = -1;
875 }
876 if (vsst->afsss != AFS_SOCKET_CHECK_FOR_WRITE) {
877 if (FD_ISSET(vsst->afs_socket, &s->rfds))
878 recv_afs_result(vsst);
879 } else if (FD_ISSET(vsst->afs_socket, &s->wfds)) {
880 PARA_NOTICE_LOG("requesting new fd from afs\n");
881 ret = send_buffer(vsst->afs_socket, "new");
882 vsst->afsss = AFS_SOCKET_AFD_PENDING;
883 }
884 for (i = 0; senders[i].name; i++) {
885 if (!senders[i].post_select)
886 continue;
887 senders[i].post_select(&s->rfds, &s->wfds);
888 }
889 if ((vss_playing() && !(mmd->vss_status_flags & VSS_PLAYING)) ||
890 (vss_next() && vss_playing()))
891 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
892 vss_send(vsst);
893 }
894
895 /**
896 * Initialize the virtual streaming system task.
897 *
898 * \param afs_socket The fd for communication with afs.
899 *
900 * This also initializes all supported senders and starts streaming
901 * if the --autoplay command line flag was given.
902 */
903 void init_vss_task(int afs_socket)
904 {
905 static struct vss_task vss_task_struct, *vsst = &vss_task_struct;
906 int i;
907 char *hn = para_hostname(), *home = para_homedir();
908 long unsigned announce_time = conf.announce_time_arg > 0?
909 conf.announce_time_arg : 300,
910 autoplay_delay = conf.autoplay_delay_arg > 0?
911 conf.autoplay_delay_arg : 0;
912 vsst->header_interval.tv_sec = 5; /* should this be configurable? */
913 vsst->afs_socket = afs_socket;
914 vsst->task.pre_select = vss_pre_select;
915 vsst->task.post_select = vss_post_select;
916 ms2tv(announce_time, &vsst->announce_tv);
917 PARA_INFO_LOG("announce timeval: %lums\n", tv2ms(&vsst->announce_tv));
918 INIT_LIST_HEAD(&fec_client_list);
919 for (i = 0; senders[i].name; i++) {
920 PARA_NOTICE_LOG("initializing %s sender\n", senders[i].name);
921 senders[i].init(&senders[i]);
922 }
923 free(hn);
924 free(home);
925 mmd->sender_cmd_data.cmd_num = -1;
926 make_empty_status_items(mmd->afd.verbose_ls_output);
927 if (conf.autoplay_given) {
928 struct timeval tmp;
929 mmd->vss_status_flags |= VSS_PLAYING;
930 mmd->new_vss_status_flags |= VSS_PLAYING;
931 ms2tv(autoplay_delay, &tmp);
932 tv_add(now, &tmp, &vsst->autoplay_barrier);
933 tv_add(&vsst->autoplay_barrier, &vsst->announce_tv,
934 &vsst->data_send_barrier);
935 }
936 register_task(&vsst->task);
937 }