Always respect the data_send_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 "string.h"
19 #include "afh.h"
20 #include "afs.h"
21 #include "server.h"
22 #include "net.h"
23 #include "server.cmdline.h"
24 #include "vss.h"
25 #include "list.h"
26 #include "send.h"
27 #include "ipc.h"
28 #include "fd.h"
29 #include "sched.h"
30
31 extern struct misc_meta_data *mmd;
32
33 extern void dccp_send_init(struct sender *);
34 extern void http_send_init(struct sender *);
35 extern void udp_send_init(struct sender *);
36
37 /** The list of supported senders. */
38 struct sender senders[] = {
39 {
40 .name = "http",
41 .init = http_send_init,
42 },
43 {
44 .name = "dccp",
45 .init = dccp_send_init,
46 },
47 {
48 .name = "udp",
49 .init = udp_send_init,
50 },
51 {
52 .name = NULL,
53 }
54 };
55
56 /** The possible states of the afs socket. */
57 enum afs_socket_status {
58 /** Socket is inactive. */
59 AFS_SOCKET_READY,
60 /** Socket fd was included in the write fd set for select(). */
61 AFS_SOCKET_CHECK_FOR_WRITE,
62 /** vss wrote a request to the socket and waits for reply from afs. */
63 AFS_SOCKET_AFD_PENDING
64 };
65
66 /** The task structure for the virtual streaming system. */
67 struct vss_task {
68 struct timeval announce_tv;
69 struct timeval data_send_barrier;
70 struct timeval eof_barrier;
71 struct timeval autoplay_barrier;
72 int afs_socket;
73 enum afs_socket_status afsss;
74 char *map;
75 struct task task;
76 const char *header_buf;
77 size_t header_len;
78 };
79
80 /**
81 * Check if vss status flag \a P (playing) is set.
82 *
83 * \return Greater than zero if playing, zero otherwise.
84 *
85 */
86 unsigned int vss_playing(void)
87 {
88 return mmd->new_vss_status_flags & VSS_PLAYING;
89 }
90
91 /**
92 * Check if the \a N (next) status flag is set.
93 *
94 * \return Greater than zero if set, zero if not.
95 *
96 */
97 unsigned int vss_next(void)
98 {
99 return mmd->new_vss_status_flags & VSS_NEXT;
100 }
101
102 /**
103 * Check if a reposition request is pending.
104 *
105 * \return Greater than zero if true, zero otherwise.
106 *
107 */
108 unsigned int vss_repos(void)
109 {
110 return mmd->new_vss_status_flags & VSS_REPOS;
111 }
112
113 /**
114 * Check if the vss is currently paused.
115 *
116 * \return Greater than zero if paused, zero otherwise.
117 *
118 */
119 unsigned int vss_paused(void)
120 {
121 return !(mmd->new_vss_status_flags & VSS_NEXT)
122 && !(mmd->new_vss_status_flags & VSS_PLAYING);
123 }
124
125 /**
126 * Check if the vss is currently stopped.
127 *
128 * \return Greater than zero if paused, zero otherwise.
129 *
130 */
131 unsigned int vss_stopped(void)
132 {
133 return (mmd->new_vss_status_flags & VSS_NEXT)
134 && !(mmd->new_vss_status_flags & VSS_PLAYING);
135 }
136
137 static int chk_barrier(const char *bname, const struct timeval *barrier,
138 struct timeval *diff, int print_log)
139 {
140 long ms;
141
142 if (tv_diff(now, barrier, diff) > 0)
143 return 1;
144 ms = tv2ms(diff);
145 if (print_log && ms)
146 PARA_DEBUG_LOG("%s barrier: %lims left\n", bname, ms);
147 return -1;
148 }
149
150 /*
151 * != NULL: timeout for next chunk
152 * NULL: nothing to do
153 */
154 static struct timeval *vss_compute_timeout(struct vss_task *vsst)
155 {
156 static struct timeval the_timeout;
157 struct timeval next_chunk;
158
159 if (vss_next() && vsst->map) {
160 /* only sleep a bit, nec*/
161 the_timeout.tv_sec = 0;
162 the_timeout.tv_usec = 100;
163 return &the_timeout;
164 }
165 if (chk_barrier("autoplay_delay", &vsst->autoplay_barrier,
166 &the_timeout, 1) < 0)
167 return &the_timeout;
168 if (chk_barrier("eof", &vsst->eof_barrier, &the_timeout, 1) < 0)
169 return &the_timeout;
170 if (chk_barrier("data send", &vsst->data_send_barrier,
171 &the_timeout, 1) < 0)
172 return &the_timeout;
173 if (!vss_playing() || !vsst->map)
174 return NULL;
175 compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
176 &mmd->stream_start, &next_chunk);
177 if (chk_barrier("chunk", &next_chunk, &the_timeout, 0) < 0)
178 return &the_timeout;
179 /* chunk is due or bof */
180 the_timeout.tv_sec = 0;
181 the_timeout.tv_usec = 0;
182 return &the_timeout;
183 }
184
185 static void vss_eof(struct vss_task *vsst)
186 {
187 mmd->stream_start = *now;
188 if (!vsst->map)
189 return;
190 if (mmd->new_vss_status_flags & VSS_NOMORE)
191 mmd->new_vss_status_flags = VSS_NEXT;
192 tv_add(&mmd->afd.afhi.eof_tv, now, &vsst->eof_barrier);
193 para_munmap(vsst->map, mmd->size);
194 vsst->map = NULL;
195 mmd->chunks_sent = 0;
196 mmd->offset = 0;
197 mmd->afd.afhi.seconds_total = 0;
198 mmd->afd.afhi.chunk_tv.tv_sec = 0;
199 mmd->afd.afhi.chunk_tv.tv_usec = 0;
200 free(mmd->afd.afhi.chunk_table);
201 mmd->afd.afhi.chunk_table = NULL;
202 free(mmd->afd.afhi.info_string);
203 mmd->afd.afhi.info_string = make_message("%s:\n%s:\n%s:\n", status_item_list[SI_AUDIO_FILE_INFO],
204 status_item_list[SI_TAGINFO1], status_item_list[SI_TAGINFO2]);
205 make_empty_status_items(mmd->afd.verbose_ls_output);
206 mmd->mtime = 0;
207 mmd->size = 0;
208 mmd->events++;
209 }
210
211 /**
212 * Get the list of all supported audio formats.
213 *
214 * \return Aa space separated list of all supported audio formats
215 * It is not allocated at runtime, i.e. there is no need to free
216 * the returned string in the caller.
217 */
218 const char *supported_audio_formats(void)
219 {
220 return SUPPORTED_AUDIO_FORMATS;
221 }
222
223 /**
224 * Get the chunk time of the current audio file.
225 *
226 * \return A pointer to a struct containing the chunk time, or NULL,
227 * if currently no audio file is selected.
228 */
229 struct timeval *vss_chunk_time(void)
230 {
231 if (mmd->afd.afhi.chunk_tv.tv_sec == 0 &&
232 mmd->afd.afhi.chunk_tv.tv_usec == 0)
233 return NULL;
234 return &mmd->afd.afhi.chunk_tv;
235 }
236
237 static int need_to_request_new_audio_file(struct vss_task *vsst)
238 {
239 if (vsst->map) /* have audio file */
240 return 0;
241 if (!vss_playing()) /* don't need one */
242 return 0;
243 if (mmd->new_vss_status_flags & VSS_NOMORE)
244 return 0;
245 if (vsst->afsss == AFS_SOCKET_AFD_PENDING) /* already requested one */
246 return 0;
247 return 1;
248 }
249
250 /**
251 * Compute the timeout for para_server's main select-loop.
252 *
253 * This function gets called from para_server to determine the timeout value
254 * for its main select loop.
255 *
256 * \param s Pointer to the server scheduler.
257 * \param t Pointer to the vss task structure.
258 *
259 * Before the timeout is computed, the current vss status flags are evaluated
260 * and acted upon by calling appropriate functions from the lower layers.
261 * Possible actions include
262 *
263 * - request a new audio file from afs,
264 * - shutdown of all senders (stop/pause command),
265 * - reposition the stream (ff/jmp command).
266 */
267 static void vss_pre_select(struct sched *s, struct task *t)
268 {
269 int i;
270 struct timeval *tv, diff;
271 struct vss_task *vsst = container_of(t, struct vss_task, task);
272
273 if (!vsst->map || vss_next() || vss_paused() || vss_repos())
274 for (i = 0; senders[i].name; i++)
275 senders[i].shutdown_clients();
276 if (vss_next())
277 vss_eof(vsst);
278 else if (vss_paused()) {
279 if (mmd->chunks_sent)
280 tv_add(&mmd->afd.afhi.eof_tv, now, &vsst->eof_barrier);
281 mmd->chunks_sent = 0;
282 } else if (vss_repos()) {
283 tv_add(&mmd->afd.afhi.eof_tv, now, &vsst->eof_barrier);
284 mmd->chunks_sent = 0;
285 mmd->current_chunk = mmd->repos_request;
286 mmd->new_vss_status_flags &= ~VSS_REPOS;
287 }
288 if (need_to_request_new_audio_file(vsst)) {
289 PARA_DEBUG_LOG("ready and playing, but no audio file\n");
290 para_fd_set(vsst->afs_socket, &s->wfds, &s->max_fileno);
291 vsst->afsss = AFS_SOCKET_CHECK_FOR_WRITE;
292 } else
293 para_fd_set(vsst->afs_socket, &s->rfds, &s->max_fileno);
294 for (i = 0; senders[i].name; i++) {
295 if (!senders[i].pre_select)
296 continue;
297 senders[i].pre_select(&s->max_fileno, &s->rfds, &s->wfds);
298 }
299 tv = vss_compute_timeout(vsst);
300 if (tv && tv_diff(tv, &s->timeout, &diff) < 0)
301 s->timeout = *tv;
302 }
303
304 static int recv_afs_msg(int afs_socket, int *fd, uint32_t *code, uint32_t *data)
305 {
306 char control[255], buf[8];
307 struct msghdr msg = {.msg_iov = NULL};
308 struct cmsghdr *cmsg;
309 struct iovec iov;
310 int ret = 0;
311
312 *fd = -1;
313 iov.iov_base = buf;
314 iov.iov_len = sizeof(buf);
315 msg.msg_iov = &iov;
316 msg.msg_iovlen = 1;
317 msg.msg_control = control;
318 msg.msg_controllen = sizeof(control);
319 memset(buf, 0, sizeof(buf));
320 ret = recvmsg(afs_socket, &msg, 0);
321 if (ret < 0)
322 return -ERRNO_TO_PARA_ERROR(errno);
323 if (iov.iov_len != sizeof(buf))
324 return -E_AFS_SHORT_READ;
325 *code = *(uint32_t*)buf;
326 *data = *(uint32_t*)(buf + 4);
327 for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
328 if (cmsg->cmsg_level != SOL_SOCKET
329 || cmsg->cmsg_type != SCM_RIGHTS)
330 continue;
331 if ((cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int) != 1)
332 continue;
333 *fd = *(int *)CMSG_DATA(cmsg);
334 }
335 return 1;
336 }
337
338 static void recv_afs_result(struct vss_task *vsst)
339 {
340 int ret, passed_fd, shmid;
341 uint32_t afs_code = 0, afs_data = 0;
342 struct stat statbuf;
343
344 vsst->afsss = AFS_SOCKET_READY;
345 mmd->afd.afhi.chunk_table = NULL;
346 ret = recv_afs_msg(vsst->afs_socket, &passed_fd, &afs_code, &afs_data);
347 if (ret < 0)
348 goto err;
349 PARA_DEBUG_LOG("fd: %d, code: %u, shmid: %u\n", passed_fd, afs_code,
350 afs_data);
351 ret = -E_NOFD;
352 if (afs_code != NEXT_AUDIO_FILE)
353 goto err;
354 if (passed_fd < 0)
355 goto err;
356 shmid = afs_data;
357 ret = load_afd(shmid, &mmd->afd);
358 if (ret < 0)
359 goto err;
360 shm_destroy(shmid);
361 ret = fstat(passed_fd, &statbuf);
362 if (ret < 0) {
363 PARA_ERROR_LOG("fstat error:\n");
364 ret = -ERRNO_TO_PARA_ERROR(errno);
365 goto err;
366 }
367 mmd->size = statbuf.st_size;
368 mmd->mtime = statbuf.st_mtime;
369 vsst->map = para_mmap(mmd->size, PROT_READ, MAP_PRIVATE,
370 passed_fd, 0);
371 close(passed_fd);
372 mmd->chunks_sent = 0;
373 mmd->current_chunk = 0;
374 mmd->offset = 0;
375 mmd->events++;
376 mmd->num_played++;
377 mmd->new_vss_status_flags &= (~VSS_NEXT);
378 afh_get_header(&mmd->afd.afhi, vsst->map, &vsst->header_buf,
379 &vsst->header_len);
380 return;
381 err:
382 free(mmd->afd.afhi.chunk_table);
383 if (passed_fd >= 0)
384 close(passed_fd);
385 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
386 mmd->new_vss_status_flags = VSS_NEXT;
387 }
388
389 /**
390 * Main sending function.
391 *
392 * This function gets called from para_server as soon as the next chunk of data
393 * should be pushed out. It obtains a pointer to the data to be sent out as
394 * well as its length from mmd->afd.afhi. This information is then passed to
395 * each supported sender's send() function which is supposed to send out the data
396 * to all connected clients.
397 */
398 static void vss_send_chunk(struct vss_task *vsst)
399 {
400 int i;
401 struct timeval due;
402 const char *buf;
403 size_t len;
404
405 if (!vsst->map || !vss_playing())
406 return;
407 compute_chunk_time(mmd->chunks_sent, &mmd->afd.afhi.chunk_tv,
408 &mmd->stream_start, &due);
409 if (tv_diff(&due, now, NULL) > 0)
410 return;
411 if (chk_barrier("eof", &vsst->eof_barrier, &due, 1) < 0)
412 return;
413 if (chk_barrier("data send", &vsst->data_send_barrier,
414 &due, 1) < 0)
415 return;
416 if (mmd->current_chunk >= mmd->afd.afhi.chunks_total) { /* eof */
417 mmd->new_vss_status_flags |= VSS_NEXT;
418 return;
419 }
420 /*
421 * We call the send function also in case of empty chunks as they
422 * might have still some data queued which can be sent in this case.
423 */
424 if (!mmd->chunks_sent) {
425 struct timeval tmp;
426 mmd->stream_start = *now;
427 tv_scale(mmd->current_chunk, &mmd->afd.afhi.chunk_tv, &tmp);
428 mmd->offset = tv2ms(&tmp);
429 mmd->events++;
430 }
431 afh_get_chunk(mmd->current_chunk, &mmd->afd.afhi, vsst->map, &buf, &len);
432 for (i = 0; senders[i].name; i++)
433 senders[i].send(mmd->current_chunk, mmd->chunks_sent, buf, len,
434 vsst->header_buf, vsst->header_len);
435 mmd->new_vss_status_flags |= VSS_PLAYING;
436 mmd->chunks_sent++;
437 mmd->current_chunk++;
438 }
439
440 static void vss_post_select(struct sched *s, struct task *t)
441 {
442 int ret, i;
443 struct vss_task *vsst = container_of(t, struct vss_task, task);
444
445 if (mmd->sender_cmd_data.cmd_num >= 0) {
446 int num = mmd->sender_cmd_data.cmd_num,
447 sender_num = mmd->sender_cmd_data.sender_num;
448
449 if (senders[sender_num].client_cmds[num])
450 senders[sender_num].client_cmds[num](&mmd->sender_cmd_data);
451 mmd->sender_cmd_data.cmd_num = -1;
452 }
453 if (vsst->afsss != AFS_SOCKET_CHECK_FOR_WRITE) {
454 if (FD_ISSET(vsst->afs_socket, &s->rfds))
455 recv_afs_result(vsst);
456 } else if (FD_ISSET(vsst->afs_socket, &s->wfds)) {
457 PARA_NOTICE_LOG("requesting new fd from afs\n");
458 ret = send_buffer(vsst->afs_socket, "new");
459 vsst->afsss = AFS_SOCKET_AFD_PENDING;
460 }
461 for (i = 0; senders[i].name; i++) {
462 if (!senders[i].post_select)
463 continue;
464 senders[i].post_select(&s->rfds, &s->wfds);
465 }
466 if (vss_playing() && !(mmd->vss_status_flags & VSS_PLAYING))
467 tv_add(now, &vsst->announce_tv, &vsst->data_send_barrier);
468 vss_send_chunk(vsst);
469 }
470
471 /**
472 * Initialize the virtual streaming system task.
473 *
474 * \param afs_socket The fd for communication with afs.
475 *
476 * This also initializes all supported senders and starts streaming
477 * if the --autoplay command line flag was given.
478 */
479 void init_vss_task(int afs_socket)
480 {
481 static struct vss_task vss_task_struct, *vsst = &vss_task_struct;
482 int i;
483 char *hn = para_hostname(), *home = para_homedir();
484 long unsigned announce_time = conf.announce_time_arg > 0?
485 conf.announce_time_arg : 300,
486 autoplay_delay = conf.autoplay_delay_arg > 0?
487 conf.autoplay_delay_arg : 0;
488
489 vsst->afs_socket = afs_socket;
490 vsst->task.pre_select = vss_pre_select;
491 vsst->task.post_select = vss_post_select;
492 ms2tv(announce_time, &vsst->announce_tv);
493 PARA_INFO_LOG("announce timeval: %lums\n", tv2ms(&vsst->announce_tv));
494 for (i = 0; senders[i].name; i++) {
495 PARA_NOTICE_LOG("initializing %s sender\n", senders[i].name);
496 senders[i].init(&senders[i]);
497 }
498 free(hn);
499 free(home);
500 mmd->sender_cmd_data.cmd_num = -1;
501 make_empty_status_items(mmd->afd.verbose_ls_output);
502 if (conf.autoplay_given) {
503 struct timeval tmp;
504 mmd->vss_status_flags |= VSS_PLAYING;
505 mmd->new_vss_status_flags |= VSS_PLAYING;
506 ms2tv(autoplay_delay, &tmp);
507 tv_add(now, &tmp, &vsst->autoplay_barrier);
508 }
509 register_task(&vsst->task);
510 }