2 * This file is part of DisOrder
3 * Copyright (C) 2005, 2006, 2007 Richard Kettlewell
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
21 /* This program deliberately does not use the garbage collector even though it
22 * might be convenient to do so. This is for two reasons. Firstly some libao
23 * drivers are implemented using threads and we do not want to have to deal
24 * with potential interactions between threading and garbage collection.
25 * Secondly this process needs to be able to respond quickly and this is not
26 * compatible with the collector hanging the program even relatively
42 #include <sys/select.h>
45 #include "configuration.h"
54 #include <alsa/asoundlib.h>
56 #define BUFFER_SECONDS 5 /* How many seconds of input to
59 #define FRAMES 4096 /* Frame batch size */
61 #define NFDS 256 /* Max FDs to poll for */
63 /* Known tracks are kept in a linked list. We don't normally to have
64 * more than two - maybe three at the outside. */
66 struct track *next; /* next track */
67 int fd; /* input FD */
69 size_t start, used; /* start + bytes used */
70 int eof; /* input is at EOF */
71 int got_format; /* got format yet? */
72 ao_sample_format format; /* sample format */
73 unsigned long long played; /* number of frames played */
74 char *buffer; /* sample buffer */
75 size_t size; /* sample buffer size */
76 int slot; /* poll array slot */
77 } *tracks, *playing; /* all tracks + playing track */
79 static time_t last_report; /* when we last reported */
80 static int paused; /* pause status */
81 static snd_pcm_t *pcm; /* current pcm handle */
82 static ao_sample_format pcm_format; /* current format if aodev != 0 */
83 static size_t bpf; /* bytes per frame */
84 static struct pollfd fds[NFDS]; /* if we need more than that */
85 static int fdno; /* fd number */
86 static snd_pcm_uframes_t pcm_bufsize; /* buffer size */
87 static snd_pcm_uframes_t last_pcm_bufsize; /* last seen buffer size */
88 static int forceplay; /* frames to force play */
90 static const struct option options[] = {
91 { "help", no_argument, 0, 'h' },
92 { "version", no_argument, 0, 'V' },
93 { "config", required_argument, 0, 'c' },
94 { "debug", no_argument, 0, 'd' },
95 { "no-debug", no_argument, 0, 'D' },
99 /* Display usage message and terminate. */
100 static void help(void) {
102 " disorder-speaker [OPTIONS]\n"
104 " --help, -h Display usage message\n"
105 " --version, -V Display version number\n"
106 " --config PATH, -c PATH Set configuration file\n"
107 " --debug, -d Turn on debugging\n"
109 "Speaker process for DisOrder. Not intended to be run\n"
115 /* Display version number and terminate. */
116 static void version(void) {
117 xprintf("disorder-speaker version %s\n", disorder_version_string);
122 /* Return the number of bytes per frame in FORMAT. */
123 static size_t bytes_per_frame(const ao_sample_format *format) {
124 return format->channels * format->bits / 8;
127 /* Find track ID, maybe creating it if not found. */
128 static struct track *findtrack(const char *id, int create) {
131 D(("findtrack %s %d", id, create));
132 for(t = tracks; t && strcmp(id, t->id); t = t->next)
135 t = xmalloc(sizeof *t);
140 /* The initial input buffer will be the sample format. */
141 t->buffer = (void *)&t->format;
142 t->size = sizeof t->format;
147 /* Remove track ID (but do not destroy it). */
148 static struct track *removetrack(const char *id) {
149 struct track *t, **tt;
151 D(("removetrack %s", id));
152 for(tt = &tracks; (t = *tt) && strcmp(id, t->id); tt = &t->next)
159 /* Destroy a track. */
160 static void destroy(struct track *t) {
161 D(("destroy %s", t->id));
162 if(t->fd != -1) xclose(t->fd);
163 if(t->buffer != (void *)&t->format) free(t->buffer);
167 /* Notice a new FD. */
168 static void acquire(struct track *t, int fd) {
169 D(("acquire %s %d", t->id, fd));
176 /* Read data into a sample buffer. Return 0 on success, -1 on EOF. */
177 static int fill(struct track *t) {
181 D(("fill %s: eof=%d used=%zu size=%zu got_format=%d",
182 t->id, t->eof, t->used, t->size, t->got_format));
183 if(t->eof) return -1;
184 if(t->used < t->size) {
185 /* there is room left in the buffer */
186 where = (t->start + t->used) % t->size;
188 /* We are reading audio data, get as much as we can */
189 if(where >= t->start) left = t->size - where;
190 else left = t->start - where;
192 /* We are still waiting for the format, only get that */
193 left = sizeof (ao_sample_format) - t->used;
195 n = read(t->fd, t->buffer + where, left);
196 } while(n < 0 && errno == EINTR);
198 if(errno != EAGAIN) fatal(errno, "error reading sample stream");
202 D(("fill %s: eof detected", t->id));
207 if(!t->got_format && t->used >= sizeof (ao_sample_format)) {
208 assert(t->used == sizeof (ao_sample_format));
209 /* Check that our assumptions are met. */
210 if(t->format.bits & 7)
211 fatal(0, "bits per sample not a multiple of 8");
212 /* Make a new buffer for audio data. */
213 t->size = bytes_per_frame(&t->format) * t->format.rate * BUFFER_SECONDS;
214 t->buffer = xmalloc(t->size);
217 D(("got format for %s", t->id));
223 /* Return true if A and B denote identical libao formats, else false. */
224 static int formats_equal(const ao_sample_format *a,
225 const ao_sample_format *b) {
226 return (a->bits == b->bits
227 && a->rate == b->rate
228 && a->channels == b->channels
229 && a->byte_format == b->byte_format);
232 /* Close the sound device. */
233 static void idle(void) {
238 if((err = snd_pcm_nonblock(pcm, 0)) < 0)
239 fatal(0, "error calling snd_pcm_nonblock: %d", err);
246 D(("released audio device"));
250 /* Abandon the current track */
251 static void abandon(void) {
252 struct speaker_message sm;
255 memset(&sm, 0, sizeof sm);
256 sm.type = SM_FINISHED;
257 strcpy(sm.id, playing->id);
258 speaker_send(1, &sm, 0);
259 removetrack(playing->id);
265 static void log_params(snd_pcm_hw_params_t *hwparams,
266 snd_pcm_sw_params_t *swparams) {
270 return; /* too verbose */
275 snd_pcm_sw_params_get_silence_size(swparams, &f);
276 info("sw silence_size=%lu", (unsigned long)f);
277 snd_pcm_sw_params_get_silence_threshold(swparams, &f);
278 info("sw silence_threshold=%lu", (unsigned long)f);
279 snd_pcm_sw_params_get_sleep_min(swparams, &u);
280 info("sw sleep_min=%lu", (unsigned long)u);
281 snd_pcm_sw_params_get_start_threshold(swparams, &f);
282 info("sw start_threshold=%lu", (unsigned long)f);
283 snd_pcm_sw_params_get_stop_threshold(swparams, &f);
284 info("sw stop_threshold=%lu", (unsigned long)f);
285 snd_pcm_sw_params_get_xfer_align(swparams, &f);
286 info("sw xfer_align=%lu", (unsigned long)f);
290 /* Make sure the sound device is open and has the right sample format. Return
291 * 0 on success and -1 on error. */
292 static int activate(void) {
294 snd_pcm_hw_params_t *hwparams;
295 snd_pcm_sw_params_t *swparams;
296 int sample_format = 0;
299 /* If we don't know the format yet we cannot start. */
300 if(!playing->got_format) {
301 D((" - not got format for %s", playing->id));
304 /* If we need to change format then close the current device. */
305 if(pcm && !formats_equal(&playing->format, &pcm_format))
309 if((err = snd_pcm_open(&pcm,
311 SND_PCM_STREAM_PLAYBACK,
312 SND_PCM_NONBLOCK))) {
313 error(0, "error from snd_pcm_open: %d", err);
316 snd_pcm_hw_params_alloca(&hwparams);
317 D(("set up hw params"));
318 if((err = snd_pcm_hw_params_any(pcm, hwparams)) < 0)
319 fatal(0, "error from snd_pcm_hw_params_any: %d", err);
320 if((err = snd_pcm_hw_params_set_access(pcm, hwparams,
321 SND_PCM_ACCESS_RW_INTERLEAVED)) < 0)
322 fatal(0, "error from snd_pcm_hw_params_set_access: %d", err);
323 switch(playing->format.bits) {
325 sample_format = SND_PCM_FORMAT_S8;
328 switch(playing->format.byte_format) {
329 case AO_FMT_NATIVE: sample_format = SND_PCM_FORMAT_S16; break;
330 case AO_FMT_LITTLE: sample_format = SND_PCM_FORMAT_S16_LE; break;
331 case AO_FMT_BIG: sample_format = SND_PCM_FORMAT_S16_BE; break;
332 error(0, "unrecognized byte format %d", playing->format.byte_format);
337 error(0, "unsupported sample size %d", playing->format.bits);
340 if((err = snd_pcm_hw_params_set_format(pcm, hwparams,
341 sample_format)) < 0) {
342 error(0, "error from snd_pcm_hw_params_set_format (%d): %d",
346 rate = playing->format.rate;
347 if((err = snd_pcm_hw_params_set_rate_near(pcm, hwparams, &rate, 0)) < 0) {
348 error(0, "error from snd_pcm_hw_params_set_rate (%d): %d",
349 playing->format.rate, err);
352 if(rate != (unsigned)playing->format.rate)
353 info("want rate %d, got %u", playing->format.rate, rate);
354 if((err = snd_pcm_hw_params_set_channels(pcm, hwparams,
355 playing->format.channels)) < 0) {
356 error(0, "error from snd_pcm_hw_params_set_channels (%d): %d",
357 playing->format.channels, err);
360 pcm_bufsize = 3 * FRAMES;
361 if((err = snd_pcm_hw_params_set_buffer_size_near(pcm, hwparams,
363 fatal(0, "error from snd_pcm_hw_params_set_buffer_size (%d): %d",
365 if(pcm_bufsize != 3 * FRAMES && pcm_bufsize != last_pcm_bufsize)
366 info("asked for PCM buffer of %d frames, got %d",
367 3 * FRAMES, (int)pcm_bufsize);
368 last_pcm_bufsize = pcm_bufsize;
369 if((err = snd_pcm_hw_params(pcm, hwparams)) < 0)
370 fatal(0, "error calling snd_pcm_hw_params: %d", err);
371 D(("set up sw params"));
372 snd_pcm_sw_params_alloca(&swparams);
373 if((err = snd_pcm_sw_params_current(pcm, swparams)) < 0)
374 fatal(0, "error calling snd_pcm_sw_params_current: %d", err);
375 if((err = snd_pcm_sw_params_set_avail_min(pcm, swparams, FRAMES)) < 0)
376 fatal(0, "error calling snd_pcm_sw_params_set_avail_min %d: %d",
378 if((err = snd_pcm_sw_params(pcm, swparams)) < 0)
379 fatal(0, "error calling snd_pcm_sw_params: %d", err);
380 pcm_format = playing->format;
381 bpf = bytes_per_frame(&pcm_format);
382 D(("acquired audio device"));
383 log_params(hwparams, swparams);
389 /* We assume the error is temporary and that we'll retry in a bit. */
397 /* Check to see whether the current track has finished playing */
398 static void maybe_finished(void) {
401 && (!playing->got_format
402 || playing->used < bytes_per_frame(&playing->format)))
406 static void play(size_t frames) {
407 snd_pcm_sframes_t written_frames;
408 size_t avail_bytes, avail_frames, written_bytes;
415 forceplay = 0; /* Must have called abandon() */
418 D(("play: play %zu/%zu%s %dHz %db %dc", frames, playing->used / bpf,
419 playing->eof ? " EOF" : "",
420 playing->format.rate,
421 playing->format.bits,
422 playing->format.channels));
423 /* If we haven't got enough bytes yet wait until we have. Exception: when
425 if(playing->used < frames * bpf && !playing->eof) {
429 /* We have got enough data so don't force play again */
431 /* Figure out how many frames there are available to write */
432 if(playing->start + playing->used > playing->size)
433 avail_bytes = playing->size - playing->start;
435 avail_bytes = playing->used;
436 avail_frames = avail_bytes / bpf;
437 if(avail_frames > frames)
438 avail_frames = frames;
441 written_frames = snd_pcm_writei(pcm,
442 playing->buffer + playing->start,
444 D(("actually play %zu frames, wrote %d",
445 avail_frames, (int)written_frames));
446 if(written_frames < 0) {
447 switch(written_frames) {
448 case -EPIPE: /* underrun */
449 error(0, "snd_pcm_writei reports underrun");
450 if((err = snd_pcm_prepare(pcm)) < 0)
451 fatal(0, "error calling snd_pcm_prepare: %d", err);
456 fatal(0, "error calling snd_pcm_writei: %d", (int)written_frames);
459 written_bytes = written_frames * bpf;
460 playing->start += written_bytes;
461 playing->used -= written_bytes;
462 playing->played += written_frames;
463 /* If the pointer is at the end of the buffer (or the buffer is completely
464 * empty) wrap it back to the start. */
465 if(!playing->used || playing->start == playing->size)
467 frames -= written_frames;
470 /* Notify the server what we're up to. */
471 static void report(void) {
472 struct speaker_message sm;
474 if(playing && playing->buffer != (void *)&playing->format) {
475 memset(&sm, 0, sizeof sm);
476 sm.type = paused ? SM_PAUSED : SM_PLAYING;
477 strcpy(sm.id, playing->id);
478 sm.data = playing->played / playing->format.rate;
479 speaker_send(1, &sm, 0);
484 static int addfd(int fd, int events) {
487 fds[fdno].events = events;
493 int main(int argc, char **argv) {
494 int n, fd, stdin_slot, alsa_slots, alsa_nslots = -1, err;
495 unsigned short alsa_revents;
497 struct speaker_message sm;
501 if(!setlocale(LC_CTYPE, "")) fatal(errno, "error calling setlocale");
502 while((n = getopt_long(argc, argv, "hVc:dD", options, 0)) >= 0) {
506 case 'c': configfile = optarg; break;
507 case 'd': debugging = 1; break;
508 case 'D': debugging = 0; break;
509 default: fatal(0, "invalid option");
512 if(getenv("DISORDER_DEBUG_SPEAKER")) debugging = 1;
513 /* If stderr is a TTY then log there, otherwise to syslog. */
515 openlog(progname, LOG_PID, LOG_DAEMON);
516 log_default = &log_syslog;
518 if(config_read()) fatal(0, "cannot read configuration");
520 signal(SIGPIPE, SIG_IGN);
522 xnice(config->nice_speaker);
525 /* make sure we're not root, whatever the config says */
526 if(getuid() == 0 || geteuid() == 0) fatal(0, "do not run as root");
528 while(getppid() != 1) {
530 /* Always ready for commands from the main server. */
531 stdin_slot = addfd(0, POLLIN);
532 /* Try to read sample data for the currently playing track if there is
534 if(playing && !playing->eof && playing->used < playing->size) {
535 playing->slot = addfd(playing->fd, POLLIN);
538 /* If forceplay is set then wait until it succeeds before waiting on the
540 if(pcm && !forceplay) {
546 alsa_nslots = snd_pcm_poll_descriptors(pcm, &fds[fdno], NFDS - fdno);
548 || !(fds[alsa_slots].events & POLLOUT))
549 && snd_pcm_state(pcm) == SND_PCM_STATE_XRUN) {
550 error(0, "underrun detected after call to snd_pcm_poll_descriptors()");
551 if((err = snd_pcm_prepare(pcm)))
552 fatal(0, "error calling snd_pcm_prepare: %d", err);
555 } while(retry-- > 0);
560 /* If any other tracks don't have a full buffer, try to read sample data
562 for(t = tracks; t; t = t->next)
564 if(!t->eof && t->used < t->size) {
565 t->slot = addfd(t->fd, POLLIN);
569 /* Wait up to a second before thinking about current state */
570 n = poll(fds, fdno, 1000);
572 if(errno == EINTR) continue;
573 fatal(errno, "error calling poll");
575 /* Play some sound before doing anything else */
576 if(alsa_slots != -1) {
577 if((err = snd_pcm_poll_descriptors_revents(pcm,
581 fatal(0, "error calling snd_pcm_poll_descriptors_revents: %d", err);
582 if(alsa_revents & POLLOUT)
585 /* Some attempt to play must have failed */
586 if(playing && !paused)
589 forceplay = 0; /* just in case */
591 /* Perhaps we have a command to process */
592 if(fds[stdin_slot].revents & POLLIN) {
593 n = speaker_recv(0, &sm, &fd);
597 D(("SM_PREPARE %s %d", sm.id, fd));
598 if(fd == -1) fatal(0, "got SM_PREPARE but no file descriptor");
599 t = findtrack(sm.id, 1);
603 D(("SM_PLAY %s %d", sm.id, fd));
604 if(playing) fatal(0, "got SM_PLAY but already playing something");
605 t = findtrack(sm.id, 1);
606 if(fd != -1) acquire(t, fd);
626 D(("SM_CANCEL %s", sm.id));
627 t = removetrack(sm.id);
630 sm.type = SM_FINISHED;
631 strcpy(sm.id, playing->id);
632 speaker_send(1, &sm, 0);
637 error(0, "SM_CANCEL for unknown track %s", sm.id);
642 if(config_read()) error(0, "cannot read configuration");
643 info("reloaded configuration");
646 error(0, "unknown message type %d", sm.type);
649 /* Read in any buffered data */
650 for(t = tracks; t; t = t->next)
651 if(t->slot != -1 && (fds[t->slot].revents & POLLIN))
653 /* We might be able to play now */
654 if(pcm && forceplay && playing && !paused)
656 /* Maybe we finished playing a track somewhere in the above */
658 /* If we don't need the sound device for now then close it for the benefit
659 * of anyone else who wants it. */
660 if((!playing || paused) && pcm)
662 /* If we've not reported out state for a second do so now. */
663 if(time(0) > last_report)
666 info("stopped (parent terminated)");
670 int main(int attribute((unused)) argc, char **argv) {
673 fatal(0, "disorder-speaker not supported on this platform");