Merge branch 't/clang_analyzer_fixes'
[paraslash.git] / vss.c
1 /*
2 * Copyright (C) 1997-2011 Andre Noll <maan@systemlinux.org>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /** \file vss.c The virtual streaming system.
8 *
9 * This contains the audio streaming code of para_server which is independent
10 * of the current audio format, audio file selector and of the activated
11 * senders.
12 */
13
14 #include <regex.h>
15 #include <osl.h>
16
17 #include "para.h"
18 #include "error.h"
19 #include "portable_io.h"
20 #include "fec.h"
21 #include "string.h"
22 #include "afh.h"
23 #include "afs.h"
24 #include "server.h"
25 #include "net.h"
26 #include "server.cmdline.h"
27 #include "list.h"
28 #include "send.h"
29 #include "vss.h"
30 #include "ipc.h"
31 #include "fd.h"
32 #include "sched.h"
33
34 extern struct misc_meta_data *mmd;
35
36 extern void dccp_send_init(struct sender *);
37 extern void http_send_init(struct sender *);
38 extern void udp_send_init(struct sender *);
39
40 /** The list of supported senders. */
41 struct sender senders[] = {
42 {
43 .name = "http",
44 .init = http_send_init,
45 },
46 {
47 .name = "dccp",
48 .init = dccp_send_init,
49 },
50 {
51 .name = "udp",
52 .init = udp_send_init,
53 },
54 {
55 .name = NULL,
56 }
57 };
58
59 /** The possible states of the afs socket. */
60 enum afs_socket_status {
61 /** Socket is inactive. */
62 AFS_SOCKET_READY,
63 /** Socket fd was included in the write fd set for select(). */
64 AFS_SOCKET_CHECK_FOR_WRITE,
65 /** vss wrote a request to the socket and waits for reply from afs. */
66 AFS_SOCKET_AFD_PENDING
67 };
68
69 /** The task structure for the virtual streaming system. */
70 struct vss_task {
71 /** Copied from the -announce_time command line option. */
72 struct timeval announce_tv;
73 /** End of the announcing interval. */
74 struct timeval data_send_barrier;
75 /** End of the EOF interval. */
76 struct timeval eof_barrier;
77 /** Only used if --autoplay_delay was given. */
78 struct timeval autoplay_barrier;
79 /** Used for afs-server communication. */
80 int afs_socket;
81 /** The current state of \a afs_socket. */
82 enum afs_socket_status afsss;
83 /** The memory mapped audio file. */
84 char *map;
85 /** Used by the scheduler. */
86 struct task task;
87 /** Pointer to the header of the mapped audio file. */
88 char *header_buf;
89 /** Length of the audio file header. */
90 size_t header_len;
91 /** Time between audio file headers are sent. */
92 struct timeval header_interval;
93 };
94
95 /**
96 * The list of currently connected fec clients.
97 *
98 * Senders may use \ref vss_add_fec_client() to add entries to the list.
99 */
100 static struct list_head fec_client_list;
101
102 /**
103 * Data associated with one FEC group.
104 *
105 * A FEC group consists of a fixed number of slices and this number is given by
106 * the \a slices_per_group parameter of struct \ref fec_client_parms. Each FEC
107 * group contains a number of chunks of the current audio file.
108 *
109 * FEC slices directly correspond to the data packages sent by the paraslash
110 * senders that use FEC. Each slice is identified by its group number and its
111 * number within the group. All slices have the same size, but the last slice
112 * of the group may not be filled entirely.
113 */
114 struct fec_group {
115 /** The number of the FEC group. */
116 uint32_t num;
117 /** Number of bytes in this group. */
118 uint32_t bytes;
119 /** The first chunk of the current audio file belonging to the group. */
120 uint32_t first_chunk;
121 /** The number of chunks contained in this group. */
122 uint32_t num_chunks;
123 /** When the first chunk was sent. */
124 struct timeval start;
125 /** The duration of the full group. */
126 struct timeval duration;
127 /** The group duration divided by the number of slices. */
128 struct timeval slice_duration;
129 /** Group contains the audio file header that occupies that many slices. */
130 uint8_t num_header_slices;
131 /** Number of bytes per slice for this group. */
132 uint16_t slice_bytes;
133 };
134
135 enum fec_client_state {
136 FEC_STATE_NONE = 0, /**< not initialized and not enabled */
137 FEC_STATE_DISABLED, /**< temporarily disabled */
138 FEC_STATE_READY_TO_RUN /**< initialized and enabled */
139 };
140
141 /**
142 * Describes one connected FEC client.
143 */
144 struct fec_client {
145 /** Current state of the client */
146 enum fec_client_state state;
147 /** The connected sender client (transport layer). */
148 struct sender_client *sc;
149 /** Parameters requested by the client. */
150 struct fec_client_parms *fcp;
151 /** Used by the core FEC code. */
152 struct fec_parms *parms;
153 /** The position of this client in the fec client list. */
154 struct list_head node;
155 /** When the first slice for this client was sent. */
156 struct timeval stream_start;
157 /** The first chunk sent to this FEC client. */
158 int first_stream_chunk;
159 /** Describes the current group. */
160 struct fec_group group;
161 /** The current slice. */
162 uint8_t current_slice_num;
163 /** The data to be FEC-encoded (point to a region within the mapped audio file). */
164 const unsigned char **src_data;
165 /** Last time an audio header was sent. */
166 struct timeval next_header_time;
167 /** Used for the last source pointer of an audio file. */
168 unsigned char *extra_src_buf;
169 /** Needed for the last slice of the audio file header. */
170 unsigned char *extra_header_buf;
171 /** Extra slices needed to store largest chunk + header. */
172 int num_extra_slices;
173 /** Contains the FEC-encoded data. */
174 unsigned char *enc_buf;
175 /** Maximal packet size. */
176 int mps;
177 };
178
179 /**
180 * Get the chunk time of the current audio file.
181 *
182 * \return A pointer to a struct containing the chunk time, or NULL,
183 * if currently no audio file is selected.
184 */
185 struct timeval *vss_chunk_time(void)
186 {
187 if (mmd->afd.afhi.chunk_tv.tv_sec == 0 &&
188 mmd->afd.afhi.chunk_tv.tv_usec == 0)
189 return NULL;
190 return &mmd->afd.afhi.chunk_tv;
191 }
192
193 /**
194 * Write a fec header to a buffer.
195 *
196 * \param buf The buffer to write to.
197 * \param h The fec header to write.
198 */
199 static void write_fec_header(struct fec_client *fc, struct vss_task *vsst)
200 {
201 char *buf = (char *)fc->enc_buf;
202 struct fec_group *g = &fc->group;
203 struct fec_client_parms *p = fc->fcp;
204
205 write_u32(buf, FEC_MAGIC);
206
207 write_u8(buf + 4, p->slices_per_group + fc->num_extra_slices);
208 write_u8(buf + 5, p->data_slices_per_group + fc->num_extra_slices);
209 write_u32(buf + 6, g->num_header_slices? vsst->header_len : 0);
210
211 write_u32(buf + 10, g->num);
212 write_u32(buf + 14, g->bytes);
213
214 write_u8(buf + 18, fc->current_slice_num);
215 write_u8(buf + 19, 0); /* unused */
216 write_u16(buf + 20, g->slice_bytes);
217 write_u8(buf + 22, g->first_chunk? 0 : 1);
218 write_u8(buf + 23, vsst->header_len? 1 : 0);
219 memset(buf + 24, 0, 8);
220 }
221
222 static bool need_audio_header(struct fec_client *fc, struct vss_task *vsst)
223 {
224 if (!mmd->current_chunk) {
225 tv_add(now, &vsst->header_interval, &fc->next_header_time);
226 return false;
227 }
228 if (!vsst->header_buf)
229 return false;
230 if (vsst->header_len == 0)
231 return false;
232 if (fc->group.num > 0) {
233 if (!fc->fcp->need_periodic_header)
234 return false;
235 if (tv_diff(&fc->next_header_time, now, NULL) > 0)
236 return false;
237 }
238 tv_add(now, &vsst->header_interval, &fc->next_header_time);
239 return true;
240 }
241
242 static bool need_data_slices(struct fec_client *fc, struct vss_task *vsst)
243 {
244 if (fc->group.num > 0)
245 return true;
246 if (!vsst->header_buf)
247 return true;
248 if (vsst->header_len == 0)
249 return true;
250 if (fc->fcp->need_periodic_header)
251 return true;
252 return false;
253 }
254
255 static int num_slices(long unsigned bytes, int max_payload, int rs)
256 {
257 int ret;
258
259 assert(max_payload > 0);
260 assert(rs > 0);
261 ret = DIV_ROUND_UP(bytes, max_payload);
262 if (ret + rs > 255)
263 return -E_BAD_CT;
264 return ret;
265 }
266
267 /* set group start and group duration */
268 static void set_group_timing(struct fec_client *fc, struct vss_task *vsst)
269 {
270 struct fec_group *g = &fc->group;
271 struct timeval *chunk_tv = vss_chunk_time();
272
273 if (!need_data_slices(fc, vsst))
274 ms2tv(200, &g->duration);
275 else
276 tv_scale(g->num_chunks, chunk_tv, &g->duration);
277 tv_divide(fc->fcp->slices_per_group + fc->num_extra_slices,
278 &g->duration, &g->slice_duration);
279 PARA_DEBUG_LOG("durations (group/chunk/slice): %lu/%lu/%lu\n",
280 tv2ms(&g->duration), tv2ms(chunk_tv), tv2ms(&g->slice_duration));
281 }
282
283 static int initialize_fec_client(struct fec_client *fc, struct vss_task *vsst)
284 {
285 int k, n, ret;
286 int hs, ds, rs; /* header/data/redundant slices */
287 struct fec_client_parms *fcp = fc->fcp;
288
289 /* set mps */
290 if (fcp->init_fec) {
291 /*
292 * Set the maximum slice size to the Maximum Packet Size if the
293 * transport protocol allows to determine this value. The user
294 * can specify a slice size up to this value.
295 */
296 ret = fcp->init_fec(fc->sc);
297 if (ret < 0)
298 return ret;
299 fc->mps = ret;
300 } else
301 fc->mps = generic_max_transport_msg_size(fc->sc->fd);
302 if (fc->mps <= FEC_HEADER_SIZE)
303 return -ERRNO_TO_PARA_ERROR(EINVAL);
304
305 rs = fc->fcp->slices_per_group - fc->fcp->data_slices_per_group;
306 ret = num_slices(vsst->header_len, fc->mps - FEC_HEADER_SIZE, rs);
307 if (ret < 0)
308 return ret;
309 hs = ret;
310 ret = num_slices(mmd->afd.max_chunk_size, fc->mps - FEC_HEADER_SIZE, rs);
311 if (ret < 0)
312 return ret;
313 ds = ret;
314 if (fc->fcp->need_periodic_header)
315 k = hs + ds;
316 else
317 k = PARA_MAX(hs, ds);
318 if (k < fc->fcp->data_slices_per_group)
319 k = fc->fcp->data_slices_per_group;
320 fc->num_extra_slices = k - fc->fcp->data_slices_per_group;
321 n = k + rs;
322 fec_free(fc->parms);
323 ret = fec_new(k, n, &fc->parms);
324 if (ret < 0)
325 return ret;
326 PARA_INFO_LOG("mps: %d, k: %d, n: %d, extra slices: %d\n",
327 fc->mps, k, n, fc->num_extra_slices);
328 fc->src_data = para_realloc(fc->src_data, k * sizeof(char *));
329 fc->enc_buf = para_realloc(fc->enc_buf, fc->mps);
330 fc->extra_src_buf = para_realloc(fc->extra_src_buf, fc->mps);
331 fc->extra_header_buf = para_realloc(fc->extra_header_buf, fc->mps);
332
333 fc->state = FEC_STATE_READY_TO_RUN;
334 fc->next_header_time.tv_sec = 0;
335 fc->stream_start = *now;
336 fc->first_stream_chunk = mmd->current_chunk;
337 return 1;
338 }
339
340 static void vss_get_chunk(int chunk_num, struct vss_task *vsst,
341 char **buf, size_t *sz)
342 {
343 /*
344 * Chunk zero is special for header streams: It is the first portion of
345 * the audio file which consists of the audio file header. It may be
346 * arbitrary large due to embedded meta data. Audio format handlers may
347 * replace the header by a stripped one with meta data omitted which is
348 * of bounded size. We always use the stripped header for streaming
349 * rather than the unmodified header (chunk zero).
350 */
351 if (chunk_num == 0 && vsst->header_len > 0) {
352 *buf = vsst->header_buf; /* stripped header */
353 *sz = vsst->header_len;
354 return;
355 }
356 afh_get_chunk(chunk_num, &mmd->afd.afhi, vsst->map, (const char **)buf,
357 sz);
358 }
359
360 static void compute_group_size(struct vss_task *vsst, struct fec_group *g,
361 int max_bytes)
362 {
363 int i, max_chunks = PARA_MAX(1LU, 150 / tv2ms(vss_chunk_time()));
364
365 g->num_chunks = 0;
366 g->bytes = 0;
367 /*
368 * Include chunks into the group until the group duration is at least
369 * 150ms. For ogg and wma, a single chunk's duration (ogg page/wma
370 * super frame) is already larger than 150ms, so a FEC group consists
371 * of exactly one chunk for these audio formats.
372 */
373 for (i = 0;; i++) {
374 char *buf;
375 size_t len;
376 int chunk_num = g->first_chunk + i;
377
378 if (g->bytes > 0 && i >= max_chunks) /* duration limit */
379 break;
380 if (chunk_num >= mmd->afd.afhi.chunks_total) /* eof */
381 break;
382 vss_get_chunk(chunk_num, vsst, &buf, &len);
383 if (g->bytes + len > max_bytes)
384 break;
385 /* Include this chunk */
386 g->bytes += len;
387 g->num_chunks++;
388 }
389 assert(g->num_chunks);
390 }
391
392 /*
393 * Compute the slice size of the next group.
394 *
395 * The FEC parameters n and k are fixed but the slice size varies per
396 * FEC group. We'd like to choose slices as small as possible to avoid
397 * unnecessary FEC calculations but large enough to guarantee that the
398 * k data slices suffice to encode the header (if needed) and the data
399 * chunk(s).
400 *
401 * Once we know the payload of the next group, we define the number s
402 * of bytes per slice for this group by
403 *
404 * s = ceil(payload / k)
405 *
406 * However, for header streams, computing s is more complicated since no
407 * overlapping of header and data slices is possible. Hence we have k >=
408 * 2 and s must satisfy
409 *
410 * (*) ceil(h / s) + ceil(d / s) <= k
411 *
412 * where h and d are payload of the header and the data chunk(s)
413 * respectively. In general there is no value for s such that (*)
414 * becomes an equality, for example if h = 4000, d = 5000 and k = 10.
415 *
416 * We use the following approach for computing a suitable value for s:
417 *
418 * Let
419 * k1 := ceil(k * min(h, d) / (h + d)),
420 * k2 := k - k1.
421 *
422 * Note that k >= 2 implies k1 > 0 and k2 > 0, so
423 *
424 * s := max(ceil(min(h, d) / k1), ceil(max(h, d) / k2))
425 *
426 * is well-defined. Inequality (*) holds for this value of s since k1
427 * slices suffice to store min(h, d) while k2 slices suffice to store
428 * max(h, d), i.e. the first addent of (*) is bounded by k1 and the
429 * second by k2.
430 *
431 * For the above example we obtain
432 *
433 * k1 = ceil(10 * 4000 / 9000) = 5, k2 = 5,
434 * s = max(4000 / 5, 5000 / 5) = 1000,
435 *
436 * which is optimal since a slice size of 999 bytes would already require
437 * 11 slices.
438 */
439 static int compute_slice_size(struct fec_client *fc, struct vss_task *vsst)
440 {
441 struct fec_group *g = &fc->group;
442 int k = fc->fcp->data_slices_per_group + fc->num_extra_slices;
443 int n = fc->fcp->slices_per_group + fc->num_extra_slices;
444 int ret, k1, k2, h, d, min, max, sum;
445 int max_slice_bytes = fc->mps - FEC_HEADER_SIZE;
446 int max_group_bytes;
447
448 if (!need_audio_header(fc, vsst)) {
449 max_group_bytes = k * max_slice_bytes;
450 g->num_header_slices = 0;
451 compute_group_size(vsst, g, max_group_bytes);
452 g->slice_bytes = DIV_ROUND_UP(g->bytes, k);
453 if (g->slice_bytes == 0)
454 g->slice_bytes = 1;
455 return 1;
456 }
457 if (!need_data_slices(fc, vsst)) {
458 g->bytes = 0;
459 g->num_chunks = 0;
460 g->slice_bytes = DIV_ROUND_UP(vsst->header_len, k);
461 g->num_header_slices = k;
462 return 1;
463 }
464 h = vsst->header_len;
465 max_group_bytes = (k - num_slices(h, max_slice_bytes, n - k))
466 * max_slice_bytes;
467 compute_group_size(vsst, g, max_group_bytes);
468 d = g->bytes;
469 if (d == 0) {
470 g->slice_bytes = DIV_ROUND_UP(h, k);
471 ret = num_slices(vsst->header_len, g->slice_bytes, n - k);
472 if (ret < 0)
473 return ret;
474 g->num_header_slices = ret;
475 return 1;
476 }
477 min = PARA_MIN(h, d);
478 max = PARA_MAX(h, d);
479 sum = h + d;
480 k1 = DIV_ROUND_UP(k * min, sum);
481 k2 = k - k1;
482 assert(k1 > 0);
483 assert(k2 > 0);
484
485 g->slice_bytes = PARA_MAX(DIV_ROUND_UP(min, k1), DIV_ROUND_UP(max, k2));
486 /*
487 * This value of s := g->slice_bytes satisfies inequality (*) above,
488 * but it might be larger than max_slice_bytes. However, we know that
489 * max_slice_bytes are sufficient to store header and data, so:
490 */
491 g->slice_bytes = PARA_MIN((int)g->slice_bytes, max_slice_bytes);
492
493 ret = num_slices(vsst->header_len, g->slice_bytes, n - k);
494 if (ret < 0)
495 return ret;
496 g->num_header_slices = ret;
497 return 1;
498 }
499
500 static int setup_next_fec_group(struct fec_client *fc, struct vss_task *vsst)
501 {
502 int ret, i, k, n, data_slices;
503 size_t len;
504 char *buf;
505 struct fec_group *g = &fc->group;
506
507 if (fc->state == FEC_STATE_NONE) {
508 ret = initialize_fec_client(fc, vsst);
509 if (ret < 0)
510 return ret;
511 g->first_chunk = mmd->current_chunk;
512 g->num = 0;
513 g->start = *now;
514 } else {
515 struct timeval tmp;
516 if (g->first_chunk + g->num_chunks >= mmd->afd.afhi.chunks_total)
517 return 0;
518 /*
519 * Start and duration of this group depend only on the previous
520 * group. Compute the new group start as g->start += g->duration.
521 */
522 tmp = g->start;
523 tv_add(&tmp, &g->duration, &g->start);
524 set_group_timing(fc, vsst);
525 g->first_chunk += g->num_chunks;
526 g->num++;
527 }
528 k = fc->fcp->data_slices_per_group + fc->num_extra_slices;
529 n = fc->fcp->slices_per_group + fc->num_extra_slices;
530
531 compute_slice_size(fc, vsst);
532 assert(g->slice_bytes > 0);
533 ret = num_slices(g->bytes, g->slice_bytes, n - k);
534 if (ret < 0)
535 return ret;
536 data_slices = ret;
537 assert(g->num_header_slices + data_slices <= k);
538 fc->current_slice_num = 0;
539 if (g->num == 0)
540 set_group_timing(fc, vsst);
541 /* setup header slices */
542 buf = vsst->header_buf;
543 for (i = 0; i < g->num_header_slices; i++) {
544 uint32_t payload_size;
545 if (buf + g->slice_bytes <= vsst->header_buf + vsst->header_len) {
546 fc->src_data[i] = (const unsigned char *)buf;
547 buf += g->slice_bytes;
548 continue;
549 }
550 /*
551 * Can not use vss->header_buf for this slice as it
552 * goes beyond the buffer. This slice will not be fully
553 * used.
554 */
555 payload_size = vsst->header_buf + vsst->header_len - buf;
556 memcpy(fc->extra_header_buf, buf, payload_size);
557 if (payload_size < g->slice_bytes)
558 memset(fc->extra_header_buf + payload_size, 0,
559 g->slice_bytes - payload_size);
560 fc->src_data[i] = fc->extra_header_buf;
561 assert(i == g->num_header_slices - 1);
562 }
563
564 /* setup data slices */
565 vss_get_chunk(g->first_chunk, vsst, &buf, &len);
566 for (; i < g->num_header_slices + data_slices; i++) {
567 if (buf + g->slice_bytes > vsst->map + mmd->size) {
568 /*
569 * Can not use the memory mapped audio file for this
570 * slice as it goes beyond the map.
571 */
572 uint32_t payload_size = vsst->map + mmd->size - buf;
573 memcpy(fc->extra_src_buf, buf, payload_size);
574 if (payload_size < g->slice_bytes)
575 memset(fc->extra_src_buf + payload_size, 0,
576 g->slice_bytes - payload_size);
577 fc->src_data[i] = fc->extra_src_buf;
578 i++;
579 break;
580 }
581 fc->src_data[i] = (const unsigned char *)buf;
582 buf += g->slice_bytes;
583 }
584 if (i < k) {
585 /* use arbitrary data for all remaining slices */
586 buf = vsst->map;
587 for (; i < k; i++)
588 fc->src_data[i] = (const unsigned char *)buf;
589 }
590 PARA_DEBUG_LOG("FEC group %d: %d chunks (%d - %d), %d bytes\n",
591 g->num, g->num_chunks, g->first_chunk,
592 g->first_chunk + g->num_chunks - 1, g->bytes
593 );
594 PARA_DEBUG_LOG("slice_bytes: %d, %d header slices, %d data slices\n",
595 g->slice_bytes, g->num_header_slices, data_slices
596 );
597 return 1;
598 }
599
600 static int compute_next_fec_slice(struct fec_client *fc, struct vss_task *vsst)
601 {
602 if (fc->state == FEC_STATE_NONE || fc->current_slice_num
603 == fc->fcp->slices_per_group + fc->num_extra_slices) {
604 int ret = setup_next_fec_group(fc, vsst);
605 if (ret == 0)
606 return 0;
607 if (ret < 0) {
608 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
609 PARA_ERROR_LOG("FEC client temporarily disabled\n");
610 fc->state = FEC_STATE_DISABLED;
611 return ret;
612 }
613 }
614 write_fec_header(fc, vsst);
615 fec_encode(fc->parms, fc->src_data, fc->enc_buf + FEC_HEADER_SIZE,
616 fc->current_slice_num, fc->group.slice_bytes);
617 return 1;
618 }
619
620 /**
621 * Return a buffer that marks the end of the stream.
622 *
623 * \param buf Result pointer.
624 * \return The length of the eof buffer.
625 *
626 * This is used for (multicast) udp streaming where closing the socket on the
627 * sender might not give rise to an eof condition at the peer.
628 */
629 size_t vss_get_fec_eof_packet(const char **buf)
630 {
631 static const char fec_eof_packet[FEC_HEADER_SIZE] = FEC_EOF_PACKET;
632 *buf = fec_eof_packet;
633 return FEC_HEADER_SIZE;
634 }
635
636 /**
637 * Add one entry to the list of active fec clients.
638 *
639 * \param sc Generic sender_client data of the transport layer.
640 * \param fcp FEC parameters as supplied by the transport layer.
641 *
642 * \return Newly allocated fec_client struct.
643 */
644 struct fec_client *vss_add_fec_client(struct sender_client *sc,
645 struct fec_client_parms *fcp)
646 {
647 struct fec_client *fc = para_calloc(sizeof(*fc));
648
649 fc->sc = sc;
650 fc->fcp = fcp;
651 para_list_add(&fc->node, &fec_client_list);
652 return fc;
653 }
654
655 /**
656 * Remove one entry from the list of active fec clients.
657 *
658 * \param fc The client to be removed.
659 */
660 void vss_del_fec_client(struct fec_client *fc)
661 {
662 list_del(&fc->node);
663 free(fc->src_data);
664 free(fc->enc_buf);
665 free(fc->extra_src_buf);
666 free(fc->extra_header_buf);
667 fec_free(fc->parms);
668 free(fc);
669 }
670
671 /*
672 * Compute if/when next slice is due. If it isn't due yet and \a diff is
673 * not \p Null, compute the time difference next - now, where
674 *
675 * next = stream_start + (first_group_chunk - first_stream_chunk)
676 * * chunk_time + slice_num * slice_time
677 */
678 static int next_slice_is_due(struct fec_client *fc, struct timeval *diff)
679 {
680 struct timeval tmp, next;
681 int ret;
682
683 if (fc->state == FEC_STATE_NONE)
684 return 1;
685 tv_scale(fc->current_slice_num, &fc->group.slice_duration, &tmp);
686 tv_add(&tmp, &fc->group.start, &next);
687 ret = tv_diff(&next, now, diff);
688 return ret < 0? 1 : 0;
689 }
690
691 static void set_eof_barrier(struct vss_task *vsst)
692 {
693 struct fec_client *fc;
694 struct timeval timeout = {1, 0}, *chunk_tv = vss_chunk_time();
695
696 if (!chunk_tv)
697 goto out;
698 list_for_each_entry(fc, &fec_client_list, node) {
699 struct timeval group_duration;
700
701 if (fc->state != FEC_STATE_READY_TO_RUN)
702 continue;
703 tv_scale(fc->group.num_chunks, chunk_tv, &group_duration);
704 if (tv_diff(&timeout, &group_duration, NULL) < 0)
705 timeout = group_duration;
706 }
707 out:
708 tv_add(now, &timeout, &vsst->eof_barrier);
709 }
710
711 /**
712 * Check if vss status flag \a P (playing) is set.
713 *
714 * \return Greater than zero if playing, zero otherwise.
715 *
716 */
717 unsigned int vss_playing(void)
718 {
719 return mmd->new_vss_status_flags & VSS_PLAYING;
720 }
721
722 /**
723 * Check if the \a N (next) status flag is set.
724 *
725 * \return Greater than zero if set, zero if not.
726 *
727 */
728 unsigned int vss_next(void)
729 {
730 return mmd->new_vss_status_flags & VSS_NEXT;
731 }
732
733 /**
734 * Check if a reposition request is pending.
735 *
736 * \return Greater than zero if true, zero otherwise.
737 *
738 */
739 unsigned int vss_repos(void)
740 {
741 return mmd->new_vss_status_flags & VSS_REPOS;
742 }
743
744 /**
745 * Check if the vss is currently paused.
746 *
747 * \return Greater than zero if paused, zero otherwise.
748 *
749 */
750 unsigned int vss_paused(void)
751 {
752 return !(mmd->new_vss_status_flags & VSS_NEXT)
753 && !(mmd->new_vss_status_flags & VSS_PLAYING);
754 }
755
756 /**
757 * Check if the vss is currently stopped.
758 *
759 * \return Greater than zero if paused, zero otherwise.
760 *
761 */
762 unsigned int vss_stopped(void)
763 {
764 return (mmd->new_vss_status_flags & VSS_NEXT)
765 && !(mmd->new_vss_status_flags & VSS_PLAYING);
766 }
767
768 static int chk_barrier(const char *bname, const struct timeval *barrier,
769 struct timeval *diff, int print_log)
770 {
771 long ms;
772
773 if (tv_diff(now, barrier, diff) > 0)
774 return 1;
775 ms = tv2ms(diff);
776 if (print_log && ms)
777 PARA_DEBUG_LOG("%s barrier: %lims left\n", bname, ms);
778 return -1;
779 }
780
781 static void vss_compute_timeout(struct sched *s, struct vss_task *vsst)
782 {
783 struct timeval tv;
784 struct fec_client *fc;
785
786 if (!vss_playing() || !vsst->map)
787 return;
788 if (vss_next() && vsst->map) /* only sleep a bit, nec*/
789 return sched_request_timeout_ms(100, s);
790
791 /* Each of these barriers must have passed until we may proceed */
792 if (sched_request_barrier(&vsst->autoplay_barrier, s) == 1)
793 return;
794 if (sched_request_barrier(&vsst->eof_barrier, s) == 1)
795 return;
796 if (sched_request_barrier(&vsst->data_send_barrier, s) == 1)
797 return;
798 /*
799 * Compute the select timeout as the minimal time until the next
800 * chunk/slice is due for any client.
801 */
802 compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
803 &mmd->stream_start, &tv);
804 if (sched_request_barrier_or_min_delay(&tv, s) == 0)
805 return;
806 list_for_each_entry(fc, &fec_client_list, node) {
807 if (fc->state != FEC_STATE_READY_TO_RUN)
808 continue;
809 if (next_slice_is_due(fc, &tv))
810 return sched_min_delay(s);
811 sched_request_timeout(&tv, s);
812 }
813 }
814
815 static void vss_eof(struct vss_task *vsst)
816 {
817
818 if (!vsst->map)
819 return;
820 if (mmd->new_vss_status_flags & VSS_NOMORE)
821 mmd->new_vss_status_flags = VSS_NEXT;
822 set_eof_barrier(vsst);
823 afh_free_header(vsst->header_buf, mmd->afd.audio_format_id);
824 vsst->header_buf = NULL;
825 para_munmap(vsst->map, mmd->size);
826 vsst->map = NULL;
827 mmd->chunks_sent = 0;
828 //mmd->offset = 0;
829 mmd->afd.afhi.seconds_total = 0;
830 mmd->afd.afhi.chunk_tv.tv_sec = 0;
831 mmd->afd.afhi.chunk_tv.tv_usec = 0;
832 free(mmd->afd.afhi.chunk_table);
833 mmd->afd.afhi.chunk_table = NULL;
834 mmd->mtime = 0;
835 mmd->size = 0;
836 mmd->events++;
837 }
838
839 static int need_to_request_new_audio_file(struct vss_task *vsst)
840 {
841 struct timeval diff;
842
843 if (vsst->map) /* have audio file */
844 return 0;
845 if (!vss_playing()) /* don't need one */
846 return 0;
847 if (mmd->new_vss_status_flags & VSS_NOMORE)
848 return 0;
849 if (vsst->afsss == AFS_SOCKET_AFD_PENDING) /* already requested one */
850 return 0;
851 if (chk_barrier("autoplay_delay", &vsst->autoplay_barrier,
852 &diff, 1) < 0)
853 return 0;
854 return 1;
855 }
856
857 static void set_mmd_offset(void)
858 {
859 struct timeval offset;
860 tv_scale(mmd->current_chunk, &mmd->afd.afhi.chunk_tv, &offset);
861 mmd->offset = tv2ms(&offset);
862 }
863
864 /**
865 * Compute the timeout for the main select-loop of the scheduler.
866 *
867 * \param s Pointer to the server scheduler.
868 * \param t Pointer to the vss task structure.
869 *
870 * Before the timeout is computed, the current vss status flags are evaluated
871 * and acted upon by calling appropriate functions from the lower layers.
872 * Possible actions include
873 *
874 * - request a new audio file from afs,
875 * - shutdown of all senders (stop/pause command),
876 * - reposition the stream (ff/jmp command).
877 */
878 static void vss_pre_select(struct sched *s, struct task *t)
879 {
880 int i;
881 struct vss_task *vsst = container_of(t, struct vss_task, task);
882
883 if (!vsst->map || vss_next() || vss_paused() || vss_repos()) {
884 struct fec_client *fc, *tmp;
885 for (i = 0; senders[i].name; i++)
886 if (senders[i].shutdown_clients)
887 senders[i].shutdown_clients();
888 list_for_each_entry_safe(fc, tmp, &fec_client_list, node)
889 fc->state = FEC_STATE_NONE;
890 mmd->stream_start.tv_sec = 0;
891 mmd->stream_start.tv_usec = 0;
892 }
893 if (vss_next())
894 vss_eof(vsst);
895 else if (vss_paused()) {
896 if (mmd->chunks_sent)
897 set_eof_barrier(vsst);
898 mmd->chunks_sent = 0;
899 } else if (vss_repos()) {
900 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
901 set_eof_barrier(vsst);
902 mmd->chunks_sent = 0;
903 mmd->current_chunk = mmd->repos_request;
904 mmd->new_vss_status_flags &= ~VSS_REPOS;
905 set_mmd_offset();
906 }
907 if (need_to_request_new_audio_file(vsst)) {
908 PARA_DEBUG_LOG("ready and playing, but no audio file\n");
909 para_fd_set(vsst->afs_socket, &s->wfds, &s->max_fileno);
910 vsst->afsss = AFS_SOCKET_CHECK_FOR_WRITE;
911 } else
912 para_fd_set(vsst->afs_socket, &s->rfds, &s->max_fileno);
913 for (i = 0; senders[i].name; i++) {
914 if (!senders[i].pre_select)
915 continue;
916 senders[i].pre_select(&s->max_fileno, &s->rfds, &s->wfds);
917 }
918 vss_compute_timeout(s, vsst);
919 }
920
921 static int recv_afs_msg(int afs_socket, int *fd, uint32_t *code, uint32_t *data)
922 {
923 char control[255], buf[8];
924 struct msghdr msg = {.msg_iov = NULL};
925 struct cmsghdr *cmsg;
926 struct iovec iov;
927 int ret = 0;
928
929 *fd = -1;
930 iov.iov_base = buf;
931 iov.iov_len = sizeof(buf);
932 msg.msg_iov = &iov;
933 msg.msg_iovlen = 1;
934 msg.msg_control = control;
935 msg.msg_controllen = sizeof(control);
936 memset(buf, 0, sizeof(buf));
937 ret = recvmsg(afs_socket, &msg, 0);
938 if (ret < 0)
939 return -ERRNO_TO_PARA_ERROR(errno);
940 if (iov.iov_len != sizeof(buf))
941 return -E_AFS_SHORT_READ;
942 *code = *(uint32_t*)buf;
943 *data = *(uint32_t*)(buf + 4);
944 for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
945 if (cmsg->cmsg_level != SOL_SOCKET
946 || cmsg->cmsg_type != SCM_RIGHTS)
947 continue;
948 if ((cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int) != 1)
949 continue;
950 *fd = *(int *)CMSG_DATA(cmsg);
951 }
952 return 1;
953 }
954
955 static void recv_afs_result(struct vss_task *vsst, fd_set *rfds)
956 {
957 int ret, passed_fd, shmid;
958 uint32_t afs_code = 0, afs_data = 0;
959 struct stat statbuf;
960
961 if (!FD_ISSET(vsst->afs_socket, rfds))
962 return;
963 ret = recv_afs_msg(vsst->afs_socket, &passed_fd, &afs_code, &afs_data);
964 if (ret == -ERRNO_TO_PARA_ERROR(EAGAIN))
965 return;
966 if (ret < 0)
967 goto err;
968 vsst->afsss = AFS_SOCKET_READY;
969 PARA_DEBUG_LOG("fd: %d, code: %u, shmid: %u\n", passed_fd, afs_code,
970 afs_data);
971 ret = -E_NOFD;
972 if (afs_code != NEXT_AUDIO_FILE)
973 goto err;
974 if (passed_fd < 0)
975 goto err;
976 shmid = afs_data;
977 ret = load_afd(shmid, &mmd->afd);
978 if (ret < 0)
979 goto err;
980 shm_destroy(shmid);
981 ret = fstat(passed_fd, &statbuf);
982 if (ret < 0) {
983 PARA_ERROR_LOG("fstat error:\n");
984 ret = -ERRNO_TO_PARA_ERROR(errno);
985 goto err;
986 }
987 mmd->size = statbuf.st_size;
988 mmd->mtime = statbuf.st_mtime;
989 ret = para_mmap(mmd->size, PROT_READ, MAP_PRIVATE, passed_fd,
990 0, &vsst->map);
991 if (ret < 0)
992 goto err;
993 close(passed_fd);
994 mmd->chunks_sent = 0;
995 mmd->current_chunk = 0;
996 mmd->offset = 0;
997 mmd->events++;
998 mmd->num_played++;
999 mmd->new_vss_status_flags &= (~VSS_NEXT);
1000 afh_get_header(&mmd->afd.afhi, mmd->afd.audio_format_id,
1001 vsst->map, mmd->size, &vsst->header_buf, &vsst->header_len);
1002 return;
1003 err:
1004 free(mmd->afd.afhi.chunk_table);
1005 if (passed_fd >= 0)
1006 close(passed_fd);
1007 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
1008 mmd->new_vss_status_flags = VSS_NEXT;
1009 }
1010
1011 /**
1012 * Main sending function.
1013 *
1014 * This function gets called from vss_post_select(). It checks whether the next
1015 * chunk of data should be pushed out. It obtains a pointer to the data to be
1016 * sent out as well as its length from mmd->afd.afhi. This information is then
1017 * passed to each supported sender's send() function as well as to the send()
1018 * functions of each registered fec client.
1019 */
1020 static void vss_send(struct vss_task *vsst)
1021 {
1022 int i, fec_active = 0;
1023 struct timeval due;
1024 struct fec_client *fc, *tmp_fc;
1025
1026 if (!vsst->map || !vss_playing())
1027 return;
1028 if (chk_barrier("eof", &vsst->eof_barrier, &due, 1) < 0)
1029 return;
1030 if (chk_barrier("data send", &vsst->data_send_barrier,
1031 &due, 1) < 0)
1032 return;
1033 list_for_each_entry_safe(fc, tmp_fc, &fec_client_list, node) {
1034 if (fc->state == FEC_STATE_DISABLED)
1035 continue;
1036 if (!next_slice_is_due(fc, NULL)) {
1037 fec_active = 1;
1038 continue;
1039 }
1040 if (compute_next_fec_slice(fc, vsst) <= 0)
1041 continue;
1042 PARA_DEBUG_LOG("sending %d:%d (%u bytes)\n", fc->group.num,
1043 fc->current_slice_num, fc->group.slice_bytes);
1044 fc->fcp->send_fec(fc->sc, (char *)fc->enc_buf,
1045 fc->group.slice_bytes + FEC_HEADER_SIZE);
1046 fc->current_slice_num++;
1047 fec_active = 1;
1048 }
1049 if (mmd->current_chunk >= mmd->afd.afhi.chunks_total) { /* eof */
1050 if (!fec_active)
1051 mmd->new_vss_status_flags |= VSS_NEXT;
1052 return;
1053 }
1054 compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
1055 &mmd->stream_start, &due);
1056 if (tv_diff(&due, now, NULL) <= 0) {
1057 char *buf;
1058 size_t len;
1059
1060 if (!mmd->chunks_sent) {
1061 mmd->stream_start = *now;
1062 mmd->events++;
1063 set_mmd_offset();
1064 }
1065 /*
1066 * We call the send function also in case of empty chunks as
1067 * they might have still some data queued which can be sent in
1068 * this case.
1069 */
1070 vss_get_chunk(mmd->current_chunk, vsst, &buf, &len);
1071 for (i = 0; senders[i].name; i++) {
1072 if (!senders[i].send)
1073 continue;
1074 senders[i].send(mmd->current_chunk, mmd->chunks_sent,
1075 buf, len, vsst->header_buf, vsst->header_len);
1076 }
1077 mmd->chunks_sent++;
1078 mmd->current_chunk++;
1079 }
1080 }
1081
1082 static void vss_post_select(struct sched *s, struct task *t)
1083 {
1084 int ret, i;
1085 struct vss_task *vsst = container_of(t, struct vss_task, task);
1086
1087
1088 if (mmd->sender_cmd_data.cmd_num >= 0) {
1089 int num = mmd->sender_cmd_data.cmd_num,
1090 sender_num = mmd->sender_cmd_data.sender_num;
1091
1092 if (senders[sender_num].client_cmds[num]) {
1093 ret = senders[sender_num].client_cmds[num]
1094 (&mmd->sender_cmd_data);
1095 if (ret < 0)
1096 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
1097 }
1098 mmd->sender_cmd_data.cmd_num = -1;
1099 }
1100 if (vsst->afsss != AFS_SOCKET_CHECK_FOR_WRITE)
1101 recv_afs_result(vsst, &s->rfds);
1102 else if (FD_ISSET(vsst->afs_socket, &s->wfds)) {
1103 PARA_NOTICE_LOG("requesting new fd from afs\n");
1104 ret = send_buffer(vsst->afs_socket, "new");
1105 if (ret < 0)
1106 PARA_CRIT_LOG("%s\n", para_strerror(-ret));
1107 else
1108 vsst->afsss = AFS_SOCKET_AFD_PENDING;
1109 }
1110 for (i = 0; senders[i].name; i++) {
1111 if (!senders[i].post_select)
1112 continue;
1113 senders[i].post_select(&s->rfds, &s->wfds);
1114 }
1115 if ((vss_playing() && !(mmd->vss_status_flags & VSS_PLAYING)) ||
1116 (vss_next() && vss_playing()))
1117 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
1118 vss_send(vsst);
1119 }
1120
1121 /**
1122 * Initialize the virtual streaming system task.
1123 *
1124 * \param afs_socket The fd for communication with afs.
1125 *
1126 * This also initializes all supported senders and starts streaming
1127 * if the --autoplay command line flag was given.
1128 */
1129 void init_vss_task(int afs_socket)
1130 {
1131 static struct vss_task vss_task_struct, *vsst = &vss_task_struct;
1132 int i;
1133 char *hn = para_hostname(), *home = para_homedir();
1134 long unsigned announce_time = conf.announce_time_arg > 0?
1135 conf.announce_time_arg : 300,
1136 autoplay_delay = conf.autoplay_delay_arg > 0?
1137 conf.autoplay_delay_arg : 0;
1138 vsst->header_interval.tv_sec = 5; /* should this be configurable? */
1139 vsst->afs_socket = afs_socket;
1140 vsst->task.pre_select = vss_pre_select;
1141 vsst->task.post_select = vss_post_select;
1142 ms2tv(announce_time, &vsst->announce_tv);
1143 PARA_INFO_LOG("announce timeval: %lums\n", tv2ms(&vsst->announce_tv));
1144 INIT_LIST_HEAD(&fec_client_list);
1145 for (i = 0; senders[i].name; i++) {
1146 PARA_NOTICE_LOG("initializing %s sender\n", senders[i].name);
1147 senders[i].init(&senders[i]);
1148 }
1149 free(hn);
1150 free(home);
1151 mmd->sender_cmd_data.cmd_num = -1;
1152 if (conf.autoplay_given) {
1153 struct timeval tmp;
1154 mmd->vss_status_flags |= VSS_PLAYING;
1155 mmd->new_vss_status_flags |= VSS_PLAYING;
1156 ms2tv(autoplay_delay, &tmp);
1157 tv_add(now, &tmp, &vsst->autoplay_barrier);
1158 tv_add(&vsst->autoplay_barrier, &vsst->announce_tv,
1159 &vsst->data_send_barrier);
1160 }
1161 sprintf(vsst->task.status, "vss task");
1162 register_task(&vsst->task);
1163 }