Merge branch 'refs/heads/t/long-help'
[paraslash.git] / vss.c
1 /* Copyright (C) 1997 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
2
3 /** \file vss.c The virtual streaming system.
4 *
5 * This contains the audio streaming code of para_server which is independent
6 * of the current audio format, audio file selector and of the activated
7 * senders.
8 */
9
10 #include <sys/socket.h>
11 #include <netinet/in.h>
12 #include <regex.h>
13 #include <osl.h>
14 #include <sys/types.h>
15 #include <arpa/inet.h>
16 #include <sys/un.h>
17 #include <netdb.h>
18 #include <lopsub.h>
19
20 #include "server.lsg.h"
21 #include "para.h"
22 #include "error.h"
23 #include "portable_io.h"
24 #include "fec.h"
25 #include "string.h"
26 #include "afh.h"
27 #include "afs.h"
28 #include "net.h"
29 #include "server.h"
30 #include "list.h"
31 #include "send.h"
32 #include "sched.h"
33 #include "vss.h"
34 #include "ipc.h"
35 #include "fd.h"
36
37 extern struct misc_meta_data *mmd;
38
39 extern void dccp_send_init(struct sender *);
40 extern void http_send_init(struct sender *);
41 extern void udp_send_init(struct sender *);
42
43 extern const struct sender udp_sender, dccp_sender, http_sender;
44 const struct sender * const senders[] = {
45 &http_sender, &dccp_sender, &udp_sender, NULL};
46
47 /** The possible states of the afs socket. */
48 enum afs_socket_status {
49 /** Socket is inactive. */
50 AFS_SOCKET_READY,
51 /** Socket fd was included in the write fd set for select(). */
52 AFS_SOCKET_CHECK_FOR_WRITE,
53 /** vss wrote a request to the socket and waits for reply from afs. */
54 AFS_SOCKET_AFD_PENDING
55 };
56
57 /** The task structure for the virtual streaming system. */
58 struct vss_task {
59 /** Copied from the -announce_time command line option. */
60 struct timeval announce_tv;
61 /** End of the announcing interval. */
62 struct timeval data_send_barrier;
63 /** End of the EOF interval. */
64 struct timeval eof_barrier;
65 /** Only used if --autoplay_delay was given. */
66 struct timeval autoplay_barrier;
67 /** Used for afs-server communication. */
68 int afs_socket;
69 /** The current state of \a afs_socket. */
70 enum afs_socket_status afsss;
71 /** The memory mapped audio file. */
72 char *map;
73 /** The size of the memory mapping. */
74 size_t mapsize;
75 /** Used by the scheduler. */
76 struct task *task;
77 /** Pointer to the header of the mapped audio file. */
78 char *header_buf;
79 /** Length of the audio file header. */
80 size_t header_len;
81 /** Time between audio file headers are sent. */
82 struct timeval header_interval;
83 /* Only used if afh supports dynamic chunks. */
84 void *afh_context;
85 };
86
87 /**
88 * The list of currently connected fec clients.
89 *
90 * Senders may use \ref vss_add_fec_client() to add entries to the list.
91 */
92 static struct list_head fec_client_list;
93
94 /**
95 * Data associated with one FEC group.
96 *
97 * A FEC group consists of a fixed number of slices and this number is given by
98 * the \a slices_per_group parameter of struct \ref fec_client_parms. Each FEC
99 * group contains a number of chunks of the current audio file.
100 *
101 * FEC slices directly correspond to the data packages sent by the paraslash
102 * senders that use FEC. Each slice is identified by its group number and its
103 * number within the group. All slices have the same size, but the last slice
104 * of the group may not be filled entirely.
105 */
106 struct fec_group {
107 /** The number of the FEC group. */
108 uint32_t num;
109 /** Number of bytes in this group. */
110 uint32_t bytes;
111 /** The first chunk of the current audio file belonging to the group. */
112 uint32_t first_chunk;
113 /** The number of chunks contained in this group. */
114 uint32_t num_chunks;
115 /** When the first chunk was sent. */
116 struct timeval start;
117 /** The duration of the full group. */
118 struct timeval duration;
119 /** The group duration divided by the number of slices. */
120 struct timeval slice_duration;
121 /** Group contains the audio file header that occupies that many slices. */
122 uint8_t num_header_slices;
123 /** Number of bytes per slice for this group. */
124 uint16_t slice_bytes;
125 };
126
127 /** A FEC client is always in one of these states. */
128 enum fec_client_state {
129 FEC_STATE_NONE = 0, /**< not initialized and not enabled */
130 FEC_STATE_DISABLED, /**< temporarily disabled */
131 FEC_STATE_READY_TO_RUN /**< initialized and enabled */
132 };
133
134 /**
135 * Describes one connected FEC client.
136 */
137 struct fec_client {
138 /** Current state of the client */
139 enum fec_client_state state;
140 /** The connected sender client (transport layer). */
141 struct sender_client *sc;
142 /** Parameters requested by the client. */
143 struct fec_client_parms *fcp;
144 /** Used by the core FEC code. */
145 struct fec_parms *parms;
146 /** The position of this client in the fec client list. */
147 struct list_head node;
148 /** When the first slice for this client was sent. */
149 struct timeval stream_start;
150 /** The first chunk sent to this FEC client. */
151 int first_stream_chunk;
152 /** Describes the current group. */
153 struct fec_group group;
154 /** The current slice. */
155 uint8_t current_slice_num;
156 /** The data to be FEC-encoded (point to a region within the mapped audio file). */
157 const unsigned char **src_data;
158 /** Last time an audio header was sent. */
159 struct timeval next_header_time;
160 /** Used for the last source pointer of an audio file. */
161 unsigned char *extra_src_buf;
162 /** Needed for the last slice of the audio file header. */
163 unsigned char *extra_header_buf;
164 /** Extra slices needed to store largest chunk + header. */
165 int num_extra_slices;
166 /** Contains the FEC-encoded data. */
167 unsigned char *enc_buf;
168 /** Maximal packet size. */
169 int mps;
170 };
171
172 /**
173 * Get the chunk time of the current audio file.
174 *
175 * \return A pointer to a struct containing the chunk time, or NULL,
176 * if currently no audio file is selected.
177 */
178 struct timeval *vss_chunk_time(void)
179 {
180 if (mmd->afd.afhi.chunk_tv.tv_sec == 0 &&
181 mmd->afd.afhi.chunk_tv.tv_usec == 0)
182 return NULL;
183 return &mmd->afd.afhi.chunk_tv;
184 }
185
186 /**
187 * Write a fec header to a buffer.
188 *
189 * \param buf The buffer to write to.
190 * \param h The fec header to write.
191 */
192 static void write_fec_header(struct fec_client *fc, struct vss_task *vsst)
193 {
194 char *buf = (char *)fc->enc_buf;
195 struct fec_group *g = &fc->group;
196 struct fec_client_parms *p = fc->fcp;
197
198 write_u32(buf, FEC_MAGIC);
199
200 write_u8(buf + 4, p->slices_per_group + fc->num_extra_slices);
201 write_u8(buf + 5, p->data_slices_per_group + fc->num_extra_slices);
202 write_u32(buf + 6, g->num_header_slices? vsst->header_len : 0);
203
204 write_u32(buf + 10, g->num);
205 write_u32(buf + 14, g->bytes);
206
207 write_u8(buf + 18, fc->current_slice_num);
208 write_u8(buf + 19, 0); /* unused */
209 write_u16(buf + 20, g->slice_bytes);
210 write_u8(buf + 22, g->first_chunk? 0 : 1);
211 write_u8(buf + 23, vsst->header_len? 1 : 0);
212 memset(buf + 24, 0, 8);
213 }
214
215 static bool need_audio_header(struct fec_client *fc, struct vss_task *vsst)
216 {
217 if (!mmd->current_chunk) {
218 tv_add(now, &vsst->header_interval, &fc->next_header_time);
219 return false;
220 }
221 if (!vsst->header_buf)
222 return false;
223 if (vsst->header_len == 0)
224 return false;
225 if (fc->group.num > 0) {
226 if (!fc->fcp->need_periodic_header)
227 return false;
228 if (tv_diff(&fc->next_header_time, now, NULL) > 0)
229 return false;
230 }
231 tv_add(now, &vsst->header_interval, &fc->next_header_time);
232 return true;
233 }
234
235 static bool need_data_slices(struct fec_client *fc, struct vss_task *vsst)
236 {
237 if (fc->group.num > 0)
238 return true;
239 if (!vsst->header_buf)
240 return true;
241 if (vsst->header_len == 0)
242 return true;
243 if (fc->fcp->need_periodic_header)
244 return true;
245 return false;
246 }
247
248 static int num_slices(long unsigned bytes, int max_payload, int rs)
249 {
250 int ret;
251
252 assert(max_payload > 0);
253 assert(rs > 0);
254 ret = DIV_ROUND_UP(bytes, max_payload);
255 if (ret + rs > 255)
256 return -E_BAD_CT;
257 return ret;
258 }
259
260 /* set group start and group duration */
261 static void set_group_timing(struct fec_client *fc, struct vss_task *vsst)
262 {
263 struct fec_group *g = &fc->group;
264 struct timeval *chunk_tv = vss_chunk_time();
265
266 if (!need_data_slices(fc, vsst))
267 ms2tv(200, &g->duration);
268 else
269 tv_scale(g->num_chunks, chunk_tv, &g->duration);
270 tv_divide(fc->fcp->slices_per_group + fc->num_extra_slices,
271 &g->duration, &g->slice_duration);
272 PARA_DEBUG_LOG("durations (group/chunk/slice): %lu/%lu/%lu\n",
273 tv2ms(&g->duration), tv2ms(chunk_tv), tv2ms(&g->slice_duration));
274 }
275
276 static int initialize_fec_client(struct fec_client *fc, struct vss_task *vsst)
277 {
278 int k, n, ret;
279 int hs, ds, rs; /* header/data/redundant slices */
280 struct fec_client_parms *fcp = fc->fcp;
281
282 /* set mps */
283 if (fcp->init_fec) {
284 /*
285 * Set the maximum slice size to the Maximum Packet Size if the
286 * transport protocol allows determination of this value. The user
287 * can specify a slice size up to this value.
288 */
289 ret = fcp->init_fec(fc->sc);
290 if (ret < 0)
291 return ret;
292 fc->mps = ret;
293 } else
294 fc->mps = generic_max_transport_msg_size(fc->sc->fd);
295 if (fc->mps <= FEC_HEADER_SIZE)
296 return -ERRNO_TO_PARA_ERROR(EINVAL);
297
298 rs = fc->fcp->slices_per_group - fc->fcp->data_slices_per_group;
299 ret = num_slices(vsst->header_len, fc->mps - FEC_HEADER_SIZE, rs);
300 if (ret < 0)
301 return ret;
302 hs = ret;
303 ret = num_slices(mmd->afd.max_chunk_size, fc->mps - FEC_HEADER_SIZE, rs);
304 if (ret < 0)
305 return ret;
306 ds = ret;
307 if (fc->fcp->need_periodic_header)
308 k = hs + ds;
309 else
310 k = PARA_MAX(hs, ds);
311 if (k < fc->fcp->data_slices_per_group)
312 k = fc->fcp->data_slices_per_group;
313 fc->num_extra_slices = k - fc->fcp->data_slices_per_group;
314 n = k + rs;
315 fec_free(fc->parms);
316 ret = fec_new(k, n, &fc->parms);
317 if (ret < 0)
318 return ret;
319 PARA_INFO_LOG("mps: %d, k: %d, n: %d, extra slices: %d\n",
320 fc->mps, k, n, fc->num_extra_slices);
321 fc->src_data = para_realloc(fc->src_data, k * sizeof(char *));
322 fc->enc_buf = para_realloc(fc->enc_buf, fc->mps);
323 fc->extra_src_buf = para_realloc(fc->extra_src_buf, fc->mps);
324 fc->extra_header_buf = para_realloc(fc->extra_header_buf, fc->mps);
325
326 fc->state = FEC_STATE_READY_TO_RUN;
327 fc->next_header_time.tv_sec = 0;
328 fc->stream_start = *now;
329 fc->first_stream_chunk = mmd->current_chunk;
330 return 1;
331 }
332
333 static int vss_get_chunk(int chunk_num, struct vss_task *vsst,
334 char **buf, size_t *sz)
335 {
336 int ret;
337
338 /*
339 * Chunk zero is special for header streams: It is the first portion of
340 * the audio file which consists of the audio file header. It may be
341 * arbitrary large due to embedded meta data. Audio format handlers may
342 * replace the header by a stripped one with meta data omitted which is
343 * of bounded size. We always use the stripped header for streaming
344 * rather than the unmodified header (chunk zero).
345 */
346 if (chunk_num == 0 && vsst->header_len > 0) {
347 assert(vsst->header_buf);
348 *buf = vsst->header_buf; /* stripped header */
349 *sz = vsst->header_len;
350 return 0;
351 }
352 ret = afh_get_chunk(chunk_num, &mmd->afd.afhi,
353 mmd->afd.audio_format_id, vsst->map, vsst->mapsize,
354 (const char **)buf, sz, &vsst->afh_context);
355 if (ret < 0) {
356 *buf = NULL;
357 *sz = 0;
358 }
359 return ret;
360 }
361
362 static int compute_group_size(struct vss_task *vsst, struct fec_group *g,
363 int max_bytes)
364 {
365 char *buf;
366 size_t len;
367 int ret, i, max_chunks = PARA_MAX(1LU, 150 / tv2ms(vss_chunk_time()));
368
369 if (g->first_chunk == 0) {
370 g->num_chunks = 1;
371 ret = vss_get_chunk(0, vsst, &buf, &len);
372 if (ret < 0)
373 return ret;
374 g->bytes = len;
375 return 0;
376 }
377
378 g->num_chunks = 0;
379 g->bytes = 0;
380 /*
381 * Include chunks into the group until the group duration is at least
382 * 150ms. For ogg and wma, a single chunk's duration (ogg page/wma
383 * super frame) is already larger than 150ms, so a FEC group consists
384 * of exactly one chunk for these audio formats.
385 */
386 for (i = 0;; i++) {
387 int chunk_num = g->first_chunk + i;
388
389 if (g->bytes > 0 && i >= max_chunks) /* duration limit */
390 break;
391 if (chunk_num >= mmd->afd.afhi.chunks_total) /* eof */
392 break;
393 ret = vss_get_chunk(chunk_num, vsst, &buf, &len);
394 if (ret < 0)
395 return ret;
396 if (g->bytes + len > max_bytes)
397 break;
398 /* Include this chunk */
399 g->bytes += len;
400 g->num_chunks++;
401 }
402 assert(g->num_chunks);
403 return 1;
404 }
405
406 /*
407 * Compute the slice size of the next group.
408 *
409 * The FEC parameters n and k are fixed but the slice size varies per
410 * FEC group. We'd like to choose slices as small as possible to avoid
411 * unnecessary FEC calculations but large enough to guarantee that the
412 * k data slices suffice to encode the header (if needed) and the data
413 * chunk(s).
414 *
415 * Once we know the payload of the next group, we define the number s
416 * of bytes per slice for this group by
417 *
418 * s = ceil(payload / k)
419 *
420 * However, for header streams, computing s is more complicated since no
421 * overlapping of header and data slices is possible. Hence we have k >=
422 * 2 and s must satisfy
423 *
424 * (*) ceil(h / s) + ceil(d / s) <= k
425 *
426 * where h and d are payload of the header and the data chunk(s)
427 * respectively. In general there is no value for s such that (*)
428 * becomes an equality, for example if h = 4000, d = 5000 and k = 10.
429 *
430 * We use the following approach for computing a suitable value for s:
431 *
432 * Let
433 * k1 := ceil(k * min(h, d) / (h + d)),
434 * k2 := k - k1.
435 *
436 * Note that k >= 2 implies k1 > 0 and k2 > 0, so
437 *
438 * s := max(ceil(min(h, d) / k1), ceil(max(h, d) / k2))
439 *
440 * is well-defined. Inequality (*) holds for this value of s since k1
441 * slices suffice to store min(h, d) while k2 slices suffice to store
442 * max(h, d), i.e. the first addent of (*) is bounded by k1 and the
443 * second by k2.
444 *
445 * For the above example we obtain
446 *
447 * k1 = ceil(10 * 4000 / 9000) = 5, k2 = 5,
448 * s = max(4000 / 5, 5000 / 5) = 1000,
449 *
450 * which is optimal since a slice size of 999 bytes would already require
451 * 11 slices.
452 */
453 static int compute_slice_size(struct fec_client *fc, struct vss_task *vsst)
454 {
455 struct fec_group *g = &fc->group;
456 int k = fc->fcp->data_slices_per_group + fc->num_extra_slices;
457 int n = fc->fcp->slices_per_group + fc->num_extra_slices;
458 int ret, k1, k2, h, d, min, max, sum;
459 int max_slice_bytes = fc->mps - FEC_HEADER_SIZE;
460 int max_group_bytes;
461
462 if (!need_audio_header(fc, vsst)) {
463 max_group_bytes = k * max_slice_bytes;
464 g->num_header_slices = 0;
465 ret = compute_group_size(vsst, g, max_group_bytes);
466 if (ret < 0)
467 return ret;
468 g->slice_bytes = DIV_ROUND_UP(g->bytes, k);
469 if (g->slice_bytes == 0)
470 g->slice_bytes = 1;
471 return 1;
472 }
473 if (!need_data_slices(fc, vsst)) {
474 g->bytes = 0;
475 g->num_chunks = 0;
476 g->slice_bytes = DIV_ROUND_UP(vsst->header_len, k);
477 g->num_header_slices = k;
478 return 1;
479 }
480 h = vsst->header_len;
481 max_group_bytes = (k - num_slices(h, max_slice_bytes, n - k))
482 * max_slice_bytes;
483 ret = compute_group_size(vsst, g, max_group_bytes);
484 if (ret < 0)
485 return ret;
486 d = g->bytes;
487 if (d == 0) {
488 g->slice_bytes = DIV_ROUND_UP(h, k);
489 ret = num_slices(vsst->header_len, g->slice_bytes, n - k);
490 if (ret < 0)
491 return ret;
492 g->num_header_slices = ret;
493 return 1;
494 }
495 min = PARA_MIN(h, d);
496 max = PARA_MAX(h, d);
497 sum = h + d;
498 k1 = DIV_ROUND_UP(k * min, sum);
499 k2 = k - k1;
500 assert(k1 > 0);
501 assert(k2 > 0);
502
503 g->slice_bytes = PARA_MAX(DIV_ROUND_UP(min, k1), DIV_ROUND_UP(max, k2));
504 /*
505 * This value of s := g->slice_bytes satisfies inequality (*) above,
506 * but it might be larger than max_slice_bytes. However, we know that
507 * max_slice_bytes are sufficient to store header and data, so:
508 */
509 g->slice_bytes = PARA_MIN((int)g->slice_bytes, max_slice_bytes);
510
511 ret = num_slices(vsst->header_len, g->slice_bytes, n - k);
512 if (ret < 0)
513 return ret;
514 g->num_header_slices = ret;
515 return 1;
516 }
517
518 static int setup_next_fec_group(struct fec_client *fc, struct vss_task *vsst)
519 {
520 int ret, i, k, n, data_slices;
521 size_t len;
522 char *buf, *p;
523 struct fec_group *g = &fc->group;
524
525 if (fc->state == FEC_STATE_NONE) {
526 ret = initialize_fec_client(fc, vsst);
527 if (ret < 0)
528 return ret;
529 g->first_chunk = mmd->current_chunk;
530 g->num = 0;
531 g->start = *now;
532 } else {
533 struct timeval tmp;
534 if (g->first_chunk + g->num_chunks >= mmd->afd.afhi.chunks_total)
535 return 0;
536 /*
537 * Start and duration of this group depend only on the previous
538 * group. Compute the new group start as g->start += g->duration.
539 */
540 tmp = g->start;
541 tv_add(&tmp, &g->duration, &g->start);
542 set_group_timing(fc, vsst);
543 g->first_chunk += g->num_chunks;
544 g->num++;
545 }
546 k = fc->fcp->data_slices_per_group + fc->num_extra_slices;
547 n = fc->fcp->slices_per_group + fc->num_extra_slices;
548
549 compute_slice_size(fc, vsst);
550 assert(g->slice_bytes > 0);
551 ret = num_slices(g->bytes, g->slice_bytes, n - k);
552 if (ret < 0)
553 return ret;
554 data_slices = ret;
555 assert(g->num_header_slices + data_slices <= k);
556 fc->current_slice_num = 0;
557 if (g->num == 0)
558 set_group_timing(fc, vsst);
559 /* setup header slices */
560 buf = vsst->header_buf;
561 for (i = 0; i < g->num_header_slices; i++) {
562 uint32_t payload_size;
563 if (buf + g->slice_bytes <= vsst->header_buf + vsst->header_len) {
564 fc->src_data[i] = (const unsigned char *)buf;
565 buf += g->slice_bytes;
566 continue;
567 }
568 /*
569 * Can not use vss->header_buf for this slice as it
570 * goes beyond the buffer. This slice will not be fully
571 * used.
572 */
573 payload_size = vsst->header_buf + vsst->header_len - buf;
574 memcpy(fc->extra_header_buf, buf, payload_size);
575 if (payload_size < g->slice_bytes)
576 memset(fc->extra_header_buf + payload_size, 0,
577 g->slice_bytes - payload_size);
578 /*
579 * There might be more than one header slice to fill although
580 * only the first one will be used. Set all header slices to
581 * our extra buffer.
582 */
583 while (i < g->num_header_slices)
584 fc->src_data[i++] = fc->extra_header_buf;
585 break; /* we don't want i to be increased. */
586 }
587
588 /*
589 * Setup data slices. Note that for ogg streams chunk 0 points to a
590 * buffer on the heap rather than to the mapped audio file.
591 */
592 ret = vss_get_chunk(g->first_chunk, vsst, &buf, &len);
593 if (ret < 0)
594 return ret;
595 for (p = buf; i < g->num_header_slices + data_slices; i++) {
596 if (p + g->slice_bytes > buf + g->bytes) {
597 /*
598 * We must make a copy for this slice since using p
599 * directly would exceed the buffer.
600 */
601 uint32_t payload_size = buf + g->bytes - p;
602 assert(payload_size + FEC_HEADER_SIZE <= fc->mps);
603 memcpy(fc->extra_src_buf, p, payload_size);
604 if (payload_size < g->slice_bytes)
605 memset(fc->extra_src_buf + payload_size, 0,
606 g->slice_bytes - payload_size);
607 fc->src_data[i] = fc->extra_src_buf;
608 i++;
609 break;
610 }
611 fc->src_data[i] = (const unsigned char *)p;
612 p += g->slice_bytes;
613 }
614 if (i < k) {
615 /* use arbitrary data for all remaining slices */
616 buf = vsst->map;
617 for (; i < k; i++)
618 fc->src_data[i] = (const unsigned char *)buf;
619 }
620 PARA_DEBUG_LOG("FEC group %u: %u chunks (%u - %u), %u bytes\n",
621 g->num, g->num_chunks, g->first_chunk,
622 g->first_chunk + g->num_chunks - 1, g->bytes
623 );
624 PARA_DEBUG_LOG("slice_bytes: %d, %d header slices, %d data slices\n",
625 g->slice_bytes, g->num_header_slices, data_slices
626 );
627 return 1;
628 }
629
630 static int compute_next_fec_slice(struct fec_client *fc, struct vss_task *vsst)
631 {
632 if (fc->state == FEC_STATE_NONE || fc->current_slice_num
633 == fc->fcp->slices_per_group + fc->num_extra_slices) {
634 int ret = setup_next_fec_group(fc, vsst);
635 if (ret == 0)
636 return 0;
637 if (ret < 0) {
638 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
639 PARA_ERROR_LOG("FEC client temporarily disabled\n");
640 fc->state = FEC_STATE_DISABLED;
641 return ret;
642 }
643 }
644 write_fec_header(fc, vsst);
645 fec_encode(fc->parms, fc->src_data, fc->enc_buf + FEC_HEADER_SIZE,
646 fc->current_slice_num, fc->group.slice_bytes);
647 return 1;
648 }
649
650 /**
651 * Return a buffer that marks the end of the stream.
652 *
653 * \param buf Result pointer.
654 * \return The length of the eof buffer.
655 *
656 * This is used for (multicast) udp streaming where closing the socket on the
657 * sender might not give rise to an eof condition at the peer.
658 */
659 size_t vss_get_fec_eof_packet(const char **buf)
660 {
661 static const char fec_eof_packet[FEC_HEADER_SIZE] = FEC_EOF_PACKET;
662 *buf = fec_eof_packet;
663 return FEC_HEADER_SIZE;
664 }
665
666 /**
667 * Add one entry to the list of active fec clients.
668 *
669 * \param sc Generic sender_client data of the transport layer.
670 * \param fcp FEC parameters as supplied by the transport layer.
671 *
672 * \return Newly allocated fec_client struct.
673 */
674 struct fec_client *vss_add_fec_client(struct sender_client *sc,
675 struct fec_client_parms *fcp)
676 {
677 struct fec_client *fc = para_calloc(sizeof(*fc));
678
679 fc->sc = sc;
680 fc->fcp = fcp;
681 para_list_add(&fc->node, &fec_client_list);
682 return fc;
683 }
684
685 /**
686 * Remove one entry from the list of active fec clients.
687 *
688 * \param fc The client to be removed.
689 */
690 void vss_del_fec_client(struct fec_client *fc)
691 {
692 list_del(&fc->node);
693 free(fc->src_data);
694 free(fc->enc_buf);
695 free(fc->extra_src_buf);
696 free(fc->extra_header_buf);
697 fec_free(fc->parms);
698 free(fc);
699 }
700
701 /*
702 * Compute if/when next slice is due. If it isn't due yet and \a diff is
703 * not \p Null, compute the time difference next - now, where
704 *
705 * next = stream_start + (first_group_chunk - first_stream_chunk)
706 * * chunk_time + slice_num * slice_time
707 */
708 static int next_slice_is_due(struct fec_client *fc, struct timeval *diff)
709 {
710 struct timeval tmp, next;
711 int ret;
712
713 if (fc->state == FEC_STATE_NONE)
714 return 1;
715 tv_scale(fc->current_slice_num, &fc->group.slice_duration, &tmp);
716 tv_add(&tmp, &fc->group.start, &next);
717 ret = tv_diff(&next, now, diff);
718 return ret < 0? 1 : 0;
719 }
720
721 static void set_eof_barrier(struct vss_task *vsst)
722 {
723 struct fec_client *fc;
724 struct timeval timeout = {1, 0}, *chunk_tv = vss_chunk_time();
725
726 if (!chunk_tv)
727 goto out;
728 list_for_each_entry(fc, &fec_client_list, node) {
729 struct timeval group_duration;
730
731 if (fc->state != FEC_STATE_READY_TO_RUN)
732 continue;
733 tv_scale(fc->group.num_chunks, chunk_tv, &group_duration);
734 if (tv_diff(&timeout, &group_duration, NULL) < 0)
735 timeout = group_duration;
736 }
737 out:
738 tv_add(now, &timeout, &vsst->eof_barrier);
739 }
740
741 /**
742 * Check if vss status flag \a P (playing) is set.
743 *
744 * \return Greater than zero if playing, zero otherwise.
745 *
746 */
747 unsigned int vss_playing(void)
748 {
749 return mmd->new_vss_status_flags & VSS_PLAYING;
750 }
751
752 /**
753 * Check if the \a N (next) status flag is set.
754 *
755 * \return Greater than zero if set, zero if not.
756 *
757 */
758 unsigned int vss_next(void)
759 {
760 return mmd->new_vss_status_flags & VSS_NEXT;
761 }
762
763 /**
764 * Check if a reposition request is pending.
765 *
766 * \return Greater than zero if true, zero otherwise.
767 *
768 */
769 unsigned int vss_repos(void)
770 {
771 return mmd->new_vss_status_flags & VSS_REPOS;
772 }
773
774 /**
775 * Check if the vss is currently paused.
776 *
777 * \return Greater than zero if paused, zero otherwise.
778 *
779 */
780 unsigned int vss_paused(void)
781 {
782 return !(mmd->new_vss_status_flags & VSS_NEXT)
783 && !(mmd->new_vss_status_flags & VSS_PLAYING);
784 }
785
786 /**
787 * Check if the vss is currently stopped.
788 *
789 * \return Greater than zero if paused, zero otherwise.
790 *
791 */
792 unsigned int vss_stopped(void)
793 {
794 return (mmd->new_vss_status_flags & VSS_NEXT)
795 && !(mmd->new_vss_status_flags & VSS_PLAYING);
796 }
797
798 static int chk_barrier(const char *bname, const struct timeval *barrier,
799 struct timeval *diff, int print_log)
800 {
801 long ms;
802
803 if (tv_diff(now, barrier, diff) > 0)
804 return 1;
805 ms = tv2ms(diff);
806 if (print_log && ms)
807 PARA_DEBUG_LOG("%s barrier: %lims left\n", bname, ms);
808 return -1;
809 }
810
811 static void vss_compute_timeout(struct sched *s, struct vss_task *vsst)
812 {
813 struct timeval tv;
814 struct fec_client *fc;
815
816 if (!vss_playing() || !vsst->map)
817 return;
818 if (vss_next() && vsst->map) /* only sleep a bit, nec*/
819 return sched_request_timeout_ms(100, s);
820
821 /* Each of these barriers must have passed until we may proceed */
822 if (sched_request_barrier(&vsst->autoplay_barrier, s) == 1)
823 return;
824 if (sched_request_barrier(&vsst->eof_barrier, s) == 1)
825 return;
826 if (sched_request_barrier(&vsst->data_send_barrier, s) == 1)
827 return;
828 /*
829 * Compute the select timeout as the minimal time until the next
830 * chunk/slice is due for any client.
831 */
832 compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
833 &mmd->stream_start, &tv);
834 if (sched_request_barrier_or_min_delay(&tv, s) == 0)
835 return;
836 list_for_each_entry(fc, &fec_client_list, node) {
837 if (fc->state != FEC_STATE_READY_TO_RUN)
838 continue;
839 if (next_slice_is_due(fc, &tv))
840 return sched_min_delay(s);
841 sched_request_timeout(&tv, s);
842 }
843 }
844
845 static void vss_eof(struct vss_task *vsst)
846 {
847
848 if (!vsst->map)
849 return;
850 if (mmd->new_vss_status_flags & VSS_NOMORE)
851 mmd->new_vss_status_flags = VSS_NEXT;
852 set_eof_barrier(vsst);
853 afh_free_header(vsst->header_buf, mmd->afd.audio_format_id);
854 vsst->header_buf = NULL;
855 para_munmap(vsst->map, vsst->mapsize);
856 vsst->map = NULL;
857 mmd->chunks_sent = 0;
858 //mmd->offset = 0;
859 mmd->afd.afhi.seconds_total = 0;
860 mmd->afd.afhi.chunk_tv.tv_sec = 0;
861 mmd->afd.afhi.chunk_tv.tv_usec = 0;
862 free(mmd->afd.afhi.chunk_table);
863 mmd->afd.afhi.chunk_table = NULL;
864 vsst->mapsize = 0;
865 afh_close(vsst->afh_context, mmd->afd.audio_format_id);
866 vsst->afh_context = NULL;
867 mmd->events++;
868 }
869
870 static int need_to_request_new_audio_file(struct vss_task *vsst)
871 {
872 struct timeval diff;
873
874 if (vsst->map) /* have audio file */
875 return 0;
876 if (!vss_playing()) /* don't need one */
877 return 0;
878 if (mmd->new_vss_status_flags & VSS_NOMORE)
879 return 0;
880 if (vsst->afsss == AFS_SOCKET_AFD_PENDING) /* already requested one */
881 return 0;
882 if (chk_barrier("autoplay_delay", &vsst->autoplay_barrier,
883 &diff, 1) < 0)
884 return 0;
885 return 1;
886 }
887
888 static void set_mmd_offset(void)
889 {
890 struct timeval offset;
891 tv_scale(mmd->current_chunk, &mmd->afd.afhi.chunk_tv, &offset);
892 mmd->offset = tv2ms(&offset);
893 }
894
895 static void vss_pre_select(struct sched *s, void *context)
896 {
897 int i;
898 struct vss_task *vsst = context;
899
900 if (need_to_request_new_audio_file(vsst)) {
901 PARA_DEBUG_LOG("ready and playing, but no audio file\n");
902 para_fd_set(vsst->afs_socket, &s->wfds, &s->max_fileno);
903 vsst->afsss = AFS_SOCKET_CHECK_FOR_WRITE;
904 } else
905 para_fd_set(vsst->afs_socket, &s->rfds, &s->max_fileno);
906 FOR_EACH_SENDER(i) {
907 if (!senders[i]->pre_select)
908 continue;
909 senders[i]->pre_select(&s->max_fileno, &s->rfds, &s->wfds);
910 }
911 vss_compute_timeout(s, vsst);
912 }
913
914 static int recv_afs_msg(int afs_socket, int *fd, uint32_t *code, uint32_t *data)
915 {
916 char control[255] __a_aligned(8), buf[8];
917 struct msghdr msg = {.msg_iov = NULL};
918 struct cmsghdr *cmsg;
919 struct iovec iov;
920 int ret = 0;
921
922 *fd = -1;
923 iov.iov_base = buf;
924 iov.iov_len = sizeof(buf);
925 msg.msg_iov = &iov;
926 msg.msg_iovlen = 1;
927 msg.msg_control = control;
928 msg.msg_controllen = sizeof(control);
929 memset(buf, 0, sizeof(buf));
930 ret = recvmsg(afs_socket, &msg, 0);
931 if (ret < 0)
932 return -ERRNO_TO_PARA_ERROR(errno);
933 if (iov.iov_len != sizeof(buf))
934 return -E_AFS_SHORT_READ;
935 *code = *(uint32_t*)buf;
936 *data = *(uint32_t*)(buf + 4);
937 for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
938 if (cmsg->cmsg_level != SOL_SOCKET
939 || cmsg->cmsg_type != SCM_RIGHTS)
940 continue;
941 if ((cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int) != 1)
942 continue;
943 *fd = *(int *)CMSG_DATA(cmsg);
944 }
945 return 1;
946 }
947
948 #ifndef MAP_POPULATE
949 #define MAP_POPULATE 0
950 #endif
951
952 static void recv_afs_result(struct vss_task *vsst, fd_set *rfds)
953 {
954 int ret, passed_fd, shmid;
955 uint32_t afs_code = 0, afs_data = 0;
956 struct stat statbuf;
957
958 if (!FD_ISSET(vsst->afs_socket, rfds))
959 return;
960 ret = recv_afs_msg(vsst->afs_socket, &passed_fd, &afs_code, &afs_data);
961 if (ret == -ERRNO_TO_PARA_ERROR(EAGAIN))
962 return;
963 if (ret < 0)
964 goto err;
965 vsst->afsss = AFS_SOCKET_READY;
966 PARA_DEBUG_LOG("fd: %d, code: %u, shmid: %u\n", passed_fd, afs_code,
967 afs_data);
968 ret = -E_NOFD;
969 if (afs_code != NEXT_AUDIO_FILE)
970 goto err;
971 if (passed_fd < 0)
972 goto err;
973 shmid = afs_data;
974 ret = load_afd(shmid, &mmd->afd);
975 if (ret < 0)
976 goto err;
977 shm_destroy(shmid);
978 ret = fstat(passed_fd, &statbuf);
979 if (ret < 0) {
980 PARA_ERROR_LOG("fstat error:\n");
981 ret = -ERRNO_TO_PARA_ERROR(errno);
982 goto err;
983 }
984 ret = para_mmap(statbuf.st_size, PROT_READ, MAP_PRIVATE | MAP_POPULATE,
985 passed_fd, &vsst->map);
986 if (ret < 0)
987 goto err;
988 vsst->mapsize = statbuf.st_size;
989 close(passed_fd);
990 mmd->chunks_sent = 0;
991 mmd->current_chunk = 0;
992 mmd->offset = 0;
993 mmd->events++;
994 mmd->num_played++;
995 mmd->new_vss_status_flags &= (~VSS_NEXT);
996 afh_get_header(&mmd->afd.afhi, mmd->afd.audio_format_id,
997 vsst->map, vsst->mapsize, &vsst->header_buf, &vsst->header_len);
998 return;
999 err:
1000 free(mmd->afd.afhi.chunk_table);
1001 if (passed_fd >= 0)
1002 close(passed_fd);
1003 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
1004 mmd->new_vss_status_flags = VSS_NEXT;
1005 }
1006
1007 /**
1008 * Main sending function.
1009 *
1010 * This function gets called from vss_post_select(). It checks whether the next
1011 * chunk of data should be pushed out. It obtains a pointer to the data to be
1012 * sent out as well as its length from mmd->afd.afhi. This information is then
1013 * passed to each supported sender's send() function as well as to the send()
1014 * functions of each registered fec client.
1015 */
1016 static void vss_send(struct vss_task *vsst)
1017 {
1018 int i, ret;
1019 bool fec_active = false;
1020 struct timeval due;
1021 struct fec_client *fc, *tmp_fc;
1022 char *buf;
1023 size_t len;
1024
1025 if (!vsst->map || !vss_playing())
1026 return;
1027 if (chk_barrier("eof", &vsst->eof_barrier, &due, 1) < 0)
1028 return;
1029 if (chk_barrier("data send", &vsst->data_send_barrier, &due, 1) < 0)
1030 return;
1031 list_for_each_entry_safe(fc, tmp_fc, &fec_client_list, node) {
1032 if (fc->state == FEC_STATE_DISABLED)
1033 continue;
1034 if (!next_slice_is_due(fc, NULL)) {
1035 fec_active = true;
1036 continue;
1037 }
1038 if (compute_next_fec_slice(fc, vsst) <= 0)
1039 continue;
1040 PARA_DEBUG_LOG("sending %u:%u (%u bytes)\n", fc->group.num,
1041 fc->current_slice_num, fc->group.slice_bytes);
1042 fc->current_slice_num++;
1043 fc->fcp->send_fec(fc->sc, (char *)fc->enc_buf,
1044 fc->group.slice_bytes + FEC_HEADER_SIZE);
1045 fec_active = true;
1046 }
1047 if (mmd->current_chunk >= mmd->afd.afhi.chunks_total) { /* eof */
1048 if (!fec_active)
1049 mmd->new_vss_status_flags |= VSS_NEXT;
1050 return;
1051 }
1052 compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
1053 &mmd->stream_start, &due);
1054 if (tv_diff(&due, now, NULL) > 0)
1055 return;
1056 if (!mmd->chunks_sent) {
1057 mmd->stream_start = *now;
1058 mmd->events++;
1059 set_mmd_offset();
1060 }
1061 ret = vss_get_chunk(mmd->current_chunk, vsst, &buf, &len);
1062 if (ret < 0) {
1063 PARA_ERROR_LOG("could not get chunk %lu: %s\n",
1064 mmd->current_chunk, para_strerror(-ret));
1065 } else {
1066 /*
1067 * We call ->send() even if len is zero because senders might
1068 * have data queued which can be sent now.
1069 */
1070 FOR_EACH_SENDER(i) {
1071 if (!senders[i]->send)
1072 continue;
1073 senders[i]->send(mmd->current_chunk, mmd->chunks_sent,
1074 buf, len, vsst->header_buf, vsst->header_len);
1075 }
1076 }
1077 mmd->chunks_sent++;
1078 mmd->current_chunk++;
1079 }
1080
1081 static int vss_post_select(struct sched *s, void *context)
1082 {
1083 int ret, i;
1084 struct vss_task *vsst = context;
1085
1086 ret = task_get_notification(vsst->task);
1087 if (ret < 0) {
1088 afh_free_header(vsst->header_buf, mmd->afd.audio_format_id);
1089 return ret;
1090 }
1091 if (!vsst->map || vss_next() || vss_paused() || vss_repos()) {
1092 /* shut down senders and fec clients */
1093 struct fec_client *fc, *tmp;
1094 FOR_EACH_SENDER(i)
1095 if (senders[i]->shutdown_clients)
1096 senders[i]->shutdown_clients();
1097 list_for_each_entry_safe(fc, tmp, &fec_client_list, node)
1098 fc->state = FEC_STATE_NONE;
1099 mmd->stream_start.tv_sec = 0;
1100 mmd->stream_start.tv_usec = 0;
1101 }
1102 if (vss_next())
1103 vss_eof(vsst);
1104 else if (vss_paused()) {
1105 if (mmd->chunks_sent)
1106 set_eof_barrier(vsst);
1107 mmd->chunks_sent = 0;
1108 } else if (vss_repos()) { /* repositioning due to ff/jmp command */
1109 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
1110 set_eof_barrier(vsst);
1111 mmd->chunks_sent = 0;
1112 mmd->current_chunk = afh_get_start_chunk(mmd->repos_request,
1113 &mmd->afd.afhi, mmd->afd.audio_format_id);
1114 mmd->new_vss_status_flags &= ~VSS_REPOS;
1115 set_mmd_offset();
1116 }
1117 /* If a sender command is pending, run it. */
1118 if (mmd->sender_cmd_data.cmd_num >= 0) {
1119 int num = mmd->sender_cmd_data.cmd_num,
1120 sender_num = mmd->sender_cmd_data.sender_num;
1121
1122 if (senders[sender_num]->client_cmds[num]) {
1123 ret = senders[sender_num]->client_cmds[num]
1124 (&mmd->sender_cmd_data);
1125 if (ret < 0)
1126 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
1127 }
1128 mmd->sender_cmd_data.cmd_num = -1;
1129 }
1130 if (vsst->afsss != AFS_SOCKET_CHECK_FOR_WRITE)
1131 recv_afs_result(vsst, &s->rfds);
1132 else if (FD_ISSET(vsst->afs_socket, &s->wfds)) {
1133 PARA_NOTICE_LOG("requesting new fd from afs\n");
1134 ret = write_buffer(vsst->afs_socket, "new");
1135 if (ret < 0)
1136 PARA_CRIT_LOG("%s\n", para_strerror(-ret));
1137 else
1138 vsst->afsss = AFS_SOCKET_AFD_PENDING;
1139 }
1140 FOR_EACH_SENDER(i) {
1141 if (!senders[i]->post_select)
1142 continue;
1143 senders[i]->post_select(&s->rfds, &s->wfds);
1144 }
1145 if ((vss_playing() && !(mmd->vss_status_flags & VSS_PLAYING)) ||
1146 (vss_next() && vss_playing()))
1147 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
1148 vss_send(vsst);
1149 return 0;
1150 }
1151
1152 /**
1153 * Initialize the virtual streaming system task.
1154 *
1155 * \param afs_socket The fd for communication with afs.
1156 * \param s The scheduler to register the vss task to.
1157 *
1158 * This also initializes all supported senders and starts streaming
1159 * if the --autoplay command line flag was given.
1160 */
1161 void vss_init(int afs_socket, struct sched *s)
1162 {
1163 static struct vss_task vss_task_struct, *vsst = &vss_task_struct;
1164 int i;
1165 long unsigned announce_time = OPT_UINT32_VAL(ANNOUNCE_TIME),
1166 autoplay_delay = OPT_UINT32_VAL(AUTOPLAY_DELAY);
1167 vsst->header_interval.tv_sec = 5; /* should this be configurable? */
1168 vsst->afs_socket = afs_socket;
1169 ms2tv(announce_time, &vsst->announce_tv);
1170 PARA_INFO_LOG("announce timeval: %lums\n", tv2ms(&vsst->announce_tv));
1171 INIT_LIST_HEAD(&fec_client_list);
1172 FOR_EACH_SENDER(i) {
1173 PARA_NOTICE_LOG("initializing %s sender\n", senders[i]->name);
1174 senders[i]->init();
1175 }
1176 mmd->sender_cmd_data.cmd_num = -1;
1177 if (OPT_GIVEN(AUTOPLAY)) {
1178 struct timeval tmp;
1179 mmd->vss_status_flags |= VSS_PLAYING;
1180 mmd->new_vss_status_flags |= VSS_PLAYING;
1181 ms2tv(autoplay_delay, &tmp);
1182 tv_add(clock_get_realtime(NULL), &tmp, &vsst->autoplay_barrier);
1183 tv_add(&vsst->autoplay_barrier, &vsst->announce_tv,
1184 &vsst->data_send_barrier);
1185 }
1186 vsst->task = task_register(&(struct task_info) {
1187 .name = "vss",
1188 .pre_select = vss_pre_select,
1189 .post_select = vss_post_select,
1190 .context = vsst,
1191 }, s);
1192 }
1193
1194 /**
1195 * Turn off the virtual streaming system.
1196 *
1197 * This is only executed on exit. It calls the ->shutdowwn method of all senders.
1198 */
1199 void vss_shutdown(void)
1200 {
1201 int i;
1202
1203 FOR_EACH_SENDER(i) {
1204 if (!senders[i]->shutdown)
1205 continue;
1206 PARA_NOTICE_LOG("shutting down %s sender\n", senders[i]->name);
1207 senders[i]->shutdown();
1208 }
1209 }