record.c revision 1.43 1 /* $NetBSD: record.c,v 1.43 2006/05/11 01:19:10 mrg Exp $ */
2
3 /*
4 * Copyright (c) 1999, 2002 Matthew R. Green
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. The name of the author may not be used to endorse or promote products
16 * derived from this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
23 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
24 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
25 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
26 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 */
30
31 /*
32 * SunOS compatible audiorecord(1)
33 */
34 #include <sys/cdefs.h>
35
36 #ifndef lint
37 __RCSID("$NetBSD: record.c,v 1.43 2006/05/11 01:19:10 mrg Exp $");
38 #endif
39
40
41 #include <sys/types.h>
42 #include <sys/audioio.h>
43 #include <sys/ioctl.h>
44 #include <sys/time.h>
45 #include <sys/uio.h>
46
47 #include <err.h>
48 #include <fcntl.h>
49 #include <paths.h>
50 #include <signal.h>
51 #include <stdio.h>
52 #include <stdlib.h>
53 #include <string.h>
54 #include <unistd.h>
55
56 #include "libaudio.h"
57 #include "auconv.h"
58
59 audio_info_t info, oinfo;
60 ssize_t total_size = -1;
61 const char *device;
62 int format = AUDIO_FORMAT_DEFAULT;
63 char *header_info;
64 char default_info[8] = { '\0', '\0', '\0', '\0', '\0', '\0', '\0', '\0' };
65 int audiofd, outfd;
66 int qflag, aflag, fflag;
67 int verbose;
68 int monitor_gain, omonitor_gain;
69 int gain;
70 int balance;
71 int port;
72 int encoding;
73 char *encoding_str;
74 int precision;
75 int sample_rate;
76 int channels;
77 struct timeval record_time;
78 struct timeval start_time;
79
80 void (*conv_func) (u_char *, int);
81
82 void usage (void);
83 int main (int, char *[]);
84 int timeleft (struct timeval *, struct timeval *);
85 void cleanup (int) __attribute__((__noreturn__));
86 int write_header_sun (void **, size_t *, int *);
87 int write_header_wav (void **, size_t *, int *);
88 void write_header (void);
89 void rewrite_header (void);
90
91 int
92 main(argc, argv)
93 int argc;
94 char *argv[];
95 {
96 u_char *buffer;
97 size_t len, bufsize;
98 int ch, no_time_limit = 1;
99 const char *defdevice = _PATH_SOUND;
100
101 while ((ch = getopt(argc, argv, "ab:C:F:c:d:e:fhi:m:P:p:qt:s:Vv:")) != -1) {
102 switch (ch) {
103 case 'a':
104 aflag++;
105 break;
106 case 'b':
107 decode_int(optarg, &balance);
108 if (balance < 0 || balance > 63)
109 errx(1, "balance must be between 0 and 63");
110 break;
111 case 'C':
112 /* Ignore, compatibility */
113 break;
114 case 'F':
115 format = audio_format_from_str(optarg);
116 if (format < 0)
117 errx(1, "Unknown audio format; supported "
118 "formats: \"sun\", \"wav\", and \"none\"");
119 break;
120 case 'c':
121 decode_int(optarg, &channels);
122 if (channels < 0 || channels > 16)
123 errx(1, "channels must be between 0 and 16");
124 break;
125 case 'd':
126 device = optarg;
127 break;
128 case 'e':
129 encoding_str = optarg;
130 break;
131 case 'f':
132 fflag++;
133 break;
134 case 'i':
135 header_info = optarg;
136 break;
137 case 'm':
138 decode_int(optarg, &monitor_gain);
139 if (monitor_gain < 0 || monitor_gain > 255)
140 errx(1, "monitor volume must be between 0 and 255");
141 break;
142 case 'P':
143 decode_int(optarg, &precision);
144 if (precision != 4 && precision != 8 &&
145 precision != 16 && precision != 24 &&
146 precision != 32)
147 errx(1, "precision must be between 4, 8, 16, 24 or 32");
148 break;
149 case 'p':
150 len = strlen(optarg);
151
152 if (strncmp(optarg, "mic", len) == 0)
153 port |= AUDIO_MICROPHONE;
154 else if (strncmp(optarg, "cd", len) == 0 ||
155 strncmp(optarg, "internal-cd", len) == 0)
156 port |= AUDIO_CD;
157 else if (strncmp(optarg, "line", len) == 0)
158 port |= AUDIO_LINE_IN;
159 else
160 errx(1,
161 "port must be `cd', `internal-cd', `mic', or `line'");
162 break;
163 case 'q':
164 qflag++;
165 break;
166 case 's':
167 decode_int(optarg, &sample_rate);
168 if (sample_rate < 0 || sample_rate > 48000 * 2) /* XXX */
169 errx(1, "sample rate must be between 0 and 96000");
170 break;
171 case 't':
172 no_time_limit = 0;
173 decode_time(optarg, &record_time);
174 break;
175 case 'V':
176 verbose++;
177 break;
178 case 'v':
179 decode_int(optarg, &gain);
180 if (gain < 0 || gain > 255)
181 errx(1, "volume must be between 0 and 255");
182 break;
183 /* case 'h': */
184 default:
185 usage();
186 /* NOTREACHED */
187 }
188 }
189 argc -= optind;
190 argv += optind;
191
192 if (argc != 1)
193 usage();
194
195 /*
196 * convert the encoding string into a value.
197 */
198 if (encoding_str) {
199 encoding = audio_enc_to_val(encoding_str);
200 if (encoding == -1)
201 errx(1, "unknown encoding, bailing...");
202 }
203 #if 0
204 else
205 encoding = AUDIO_ENCODING_ULAW;
206 #endif
207
208 /*
209 * open the output file
210 */
211 if (argv[0][0] != '-' || argv[0][1] != '\0') {
212 /* intuit the file type from the name */
213 if (format == AUDIO_FORMAT_DEFAULT)
214 {
215 size_t flen = strlen(*argv);
216 const char *arg = *argv;
217
218 if (strcasecmp(arg + flen - 3, ".au") == 0)
219 format = AUDIO_FORMAT_SUN;
220 else if (strcasecmp(arg + flen - 4, ".wav") == 0)
221 format = AUDIO_FORMAT_WAV;
222 }
223 outfd = open(*argv, O_CREAT|(aflag ? O_APPEND : O_TRUNC)|O_WRONLY, 0666);
224 if (outfd < 0)
225 err(1, "could not open %s", *argv);
226 } else
227 outfd = STDOUT_FILENO;
228
229 /*
230 * open the audio device
231 */
232 if (device == NULL && (device = getenv("AUDIODEVICE")) == NULL &&
233 (device = getenv("AUDIODEV")) == NULL) /* Sun compatibility */
234 device = defdevice;
235
236 audiofd = open(device, O_RDONLY);
237 if (audiofd < 0 && device == defdevice) {
238 device = _PATH_SOUND0;
239 audiofd = open(device, O_RDONLY);
240 }
241 if (audiofd < 0)
242 err(1, "failed to open %s", device);
243
244 /*
245 * work out the buffer size to use, and allocate it. also work out
246 * what the old monitor gain value is, so that we can reset it later.
247 */
248 if (ioctl(audiofd, AUDIO_GETINFO, &oinfo) < 0)
249 err(1, "failed to get audio info");
250 bufsize = oinfo.record.buffer_size;
251 if (bufsize < 32 * 1024)
252 bufsize = 32 * 1024;
253 omonitor_gain = oinfo.monitor_gain;
254
255 buffer = malloc(bufsize);
256 if (buffer == NULL)
257 err(1, "couldn't malloc buffer of %d size", (int)bufsize);
258
259 /*
260 * set up audio device for recording with the speified parameters
261 */
262 AUDIO_INITINFO(&info);
263
264 /*
265 * for these, get the current values for stuffing into the header
266 */
267 #define SETINFO(x) if (x) \
268 info.record.x = x; \
269 else \
270 info.record.x = x = oinfo.record.x;
271 SETINFO (sample_rate)
272 SETINFO (channels)
273 SETINFO (precision)
274 SETINFO (encoding)
275 SETINFO (gain)
276 SETINFO (port)
277 SETINFO (balance)
278 #undef SETINFO
279
280 if (monitor_gain)
281 info.monitor_gain = monitor_gain;
282 else
283 monitor_gain = oinfo.monitor_gain;
284
285 info.mode = AUMODE_RECORD;
286 if (ioctl(audiofd, AUDIO_SETINFO, &info) < 0)
287 err(1, "failed to set audio info");
288
289 signal(SIGINT, cleanup);
290 write_header();
291 total_size = 0;
292
293 if (verbose && conv_func) {
294 const char *s = NULL;
295
296 if (conv_func == swap_bytes)
297 s = "swap bytes (16 bit)";
298 else if (conv_func == swap_bytes32)
299 s = "swap bytes (32 bit)";
300 else if (conv_func == change_sign16_be)
301 s = "change sign (big-endian, 16 bit)";
302 else if (conv_func == change_sign16_le)
303 s = "change sign (little-endian, 16 bit)";
304 else if (conv_func == change_sign32_be)
305 s = "change sign (big-endian, 32 bit)";
306 else if (conv_func == change_sign32_le)
307 s = "change sign (little-endian, 32 bit)";
308 else if (conv_func == change_sign16_swap_bytes_be)
309 s = "change sign & swap bytes (big-endian, 16 bit)";
310 else if (conv_func == change_sign16_swap_bytes_le)
311 s = "change sign & swap bytes (little-endian, 16 bit)";
312 else if (conv_func == change_sign32_swap_bytes_be)
313 s = "change sign (big-endian, 32 bit)";
314 else if (conv_func == change_sign32_swap_bytes_le)
315 s = "change sign & swap bytes (little-endian, 32 bit)";
316
317 if (s)
318 fprintf(stderr, "%s: converting, using function: %s\n",
319 getprogname(), s);
320 else
321 fprintf(stderr, "%s: using unnamed conversion "
322 "function\n", getprogname());
323 }
324
325 if (verbose)
326 fprintf(stderr,
327 "sample_rate=%d channels=%d precision=%d encoding=%s\n",
328 info.record.sample_rate, info.record.channels,
329 info.record.precision,
330 audio_enc_from_val(info.record.encoding));
331
332 if (!no_time_limit && verbose)
333 fprintf(stderr, "recording for %lu seconds, %lu microseconds\n",
334 (u_long)record_time.tv_sec, (u_long)record_time.tv_usec);
335
336 (void)gettimeofday(&start_time, NULL);
337 while (no_time_limit || timeleft(&start_time, &record_time)) {
338 if (read(audiofd, buffer, bufsize) != bufsize)
339 err(1, "read failed");
340 if (conv_func)
341 (*conv_func)(buffer, bufsize);
342 if (write(outfd, buffer, bufsize) != bufsize)
343 err(1, "write failed");
344 total_size += bufsize;
345 }
346 cleanup(0);
347 }
348
349 int
350 timeleft(start_tvp, record_tvp)
351 struct timeval *start_tvp;
352 struct timeval *record_tvp;
353 {
354 struct timeval now, diff;
355
356 (void)gettimeofday(&now, NULL);
357 timersub(&now, start_tvp, &diff);
358 timersub(record_tvp, &diff, &now);
359
360 return (now.tv_sec > 0 || (now.tv_sec == 0 && now.tv_usec > 0));
361 }
362
363 void
364 cleanup(signo)
365 int signo;
366 {
367
368 rewrite_header();
369 close(outfd);
370 if (omonitor_gain) {
371 AUDIO_INITINFO(&info);
372 info.monitor_gain = omonitor_gain;
373 if (ioctl(audiofd, AUDIO_SETINFO, &info) < 0)
374 err(1, "failed to reset audio info");
375 }
376 close(audiofd);
377 exit(0);
378 }
379
380 int
381 write_header_sun(hdrp, lenp, leftp)
382 void **hdrp;
383 size_t *lenp;
384 int *leftp;
385 {
386 static int warned = 0;
387 static sun_audioheader auh;
388 int sunenc, oencoding = encoding;
389
390 /* only perform conversions if we don't specify the encoding */
391 switch (encoding) {
392 case AUDIO_ENCODING_ULINEAR_LE:
393 #if BYTE_ORDER == LITTLE_ENDIAN
394 case AUDIO_ENCODING_ULINEAR:
395 #endif
396 if (precision == 16)
397 conv_func = change_sign16_swap_bytes_le;
398 else if (precision == 32)
399 conv_func = change_sign32_swap_bytes_le;
400 if (conv_func)
401 encoding = AUDIO_ENCODING_SLINEAR_BE;
402 break;
403
404 case AUDIO_ENCODING_ULINEAR_BE:
405 #if BYTE_ORDER == BIG_ENDIAN
406 case AUDIO_ENCODING_ULINEAR:
407 #endif
408 if (precision == 16)
409 conv_func = change_sign16_be;
410 else if (precision == 32)
411 conv_func = change_sign32_be;
412 if (conv_func)
413 encoding = AUDIO_ENCODING_SLINEAR_BE;
414 break;
415
416 case AUDIO_ENCODING_SLINEAR_LE:
417 #if BYTE_ORDER == LITTLE_ENDIAN
418 case AUDIO_ENCODING_SLINEAR:
419 #endif
420 if (precision == 16)
421 conv_func = swap_bytes;
422 else if (precision == 32)
423 conv_func = swap_bytes32;
424 if (conv_func)
425 encoding = AUDIO_ENCODING_SLINEAR_BE;
426 break;
427
428 #if BYTE_ORDER == BIG_ENDIAN
429 case AUDIO_ENCODING_SLINEAR:
430 encoding = AUDIO_ENCODING_SLINEAR_BE;
431 break;
432 #endif
433 }
434
435 /* if we can't express this as a Sun header, don't write any */
436 if (audio_encoding_to_sun(encoding, precision, &sunenc) != 0) {
437 if (!qflag && !warned) {
438 const char *s = audio_enc_from_val(oencoding);
439
440 if (s == NULL)
441 s = "(unknown)";
442 warnx("failed to convert to sun encoding from %s "
443 "(precision %d);\nSun audio header not written",
444 s, precision);
445 }
446 format = AUDIO_FORMAT_NONE;
447 conv_func = 0;
448 warned = 1;
449 return -1;
450 }
451
452 auh.magic = htonl(AUDIO_FILE_MAGIC);
453 if (outfd == STDOUT_FILENO)
454 auh.data_size = htonl(AUDIO_UNKNOWN_SIZE);
455 else if (total_size != -1)
456 auh.data_size = htonl(total_size);
457 else
458 auh.data_size = 0;
459 auh.encoding = htonl(sunenc);
460 auh.sample_rate = htonl(sample_rate);
461 auh.channels = htonl(channels);
462 if (header_info) {
463 int len, infolen;
464
465 infolen = ((len = strlen(header_info)) + 7) & 0xfffffff8;
466 *leftp = infolen - len;
467 auh.hdr_size = htonl(sizeof(auh) + infolen);
468 } else {
469 *leftp = sizeof(default_info);
470 auh.hdr_size = htonl(sizeof(auh) + *leftp);
471 }
472 *(sun_audioheader **)hdrp = &auh;
473 *lenp = sizeof auh;
474 return 0;
475 }
476
477 int
478 write_header_wav(hdrp, lenp, leftp)
479 void **hdrp;
480 size_t *lenp;
481 int *leftp;
482 {
483 /*
484 * WAV header we write looks like this:
485 *
486 * bytes purpose
487 * 0-3 "RIFF"
488 * 4-7 file length (minus 8)
489 * 8-15 "WAVEfmt "
490 * 16-19 format size
491 * 20-21 format tag
492 * 22-23 number of channels
493 * 24-27 sample rate
494 * 28-31 average bytes per second
495 * 32-33 block alignment
496 * 34-35 bits per sample
497 *
498 * then for ULAW and ALAW outputs, we have an extended chunk size
499 * and a WAV "fact" to add:
500 *
501 * 36-37 length of extension (== 0)
502 * 38-41 "fact"
503 * 42-45 fact size
504 * 46-49 number of samples written
505 * 50-53 "data"
506 * 54-57 data length
507 * 58- raw audio data
508 *
509 * for PCM outputs we have just the data remaining:
510 *
511 * 36-39 "data"
512 * 40-43 data length
513 * 44- raw audio data
514 *
515 * RIFF\^@^C^@WAVEfmt ^P^@^@^@^A^@^B^@D<AC>^@^@^P<B1>^B^@^D^@^P^@data^@^@^C^@^@^@^@^@^@^@^@^@^@
516 */
517 char wavheaderbuf[64], *p = wavheaderbuf;
518 const char *riff = "RIFF",
519 *wavefmt = "WAVEfmt ",
520 *fact = "fact",
521 *data = "data";
522 u_int32_t filelen, fmtsz, sps, abps, factsz = 4, nsample, datalen;
523 u_int16_t fmttag, nchan, align, bps, extln = 0;
524
525 if (header_info)
526 warnx("header information not supported for WAV");
527 *leftp = 0;
528
529 switch (precision) {
530 case 8:
531 bps = 8;
532 break;
533 case 16:
534 bps = 16;
535 break;
536 case 32:
537 bps = 32;
538 break;
539 default:
540 {
541 static int warned = 0;
542
543 if (warned == 0) {
544 warnx("can not support precision of %d", precision);
545 warned = 1;
546 }
547 }
548 return (-1);
549 }
550
551 switch (encoding) {
552 case AUDIO_ENCODING_ULAW:
553 fmttag = WAVE_FORMAT_MULAW;
554 fmtsz = 18;
555 align = channels;
556 break;
557
558 case AUDIO_ENCODING_ALAW:
559 fmttag = WAVE_FORMAT_ALAW;
560 fmtsz = 18;
561 align = channels;
562 break;
563
564 /*
565 * we could try to support RIFX but it seems to be more portable
566 * to output little-endian data for WAV files.
567 */
568 case AUDIO_ENCODING_ULINEAR_BE:
569 #if BYTE_ORDER == BIG_ENDIAN
570 case AUDIO_ENCODING_ULINEAR:
571 #endif
572 if (bps == 16)
573 conv_func = change_sign16_swap_bytes_be;
574 else if (bps == 32)
575 conv_func = change_sign32_swap_bytes_be;
576 goto fmt_pcm;
577
578 case AUDIO_ENCODING_SLINEAR_BE:
579 #if BYTE_ORDER == BIG_ENDIAN
580 case AUDIO_ENCODING_SLINEAR:
581 #endif
582 if (bps == 8)
583 conv_func = change_sign8;
584 else if (bps == 16)
585 conv_func = swap_bytes;
586 else if (bps == 32)
587 conv_func = swap_bytes32;
588 goto fmt_pcm;
589
590 case AUDIO_ENCODING_ULINEAR_LE:
591 #if BYTE_ORDER == LITTLE_ENDIAN
592 case AUDIO_ENCODING_ULINEAR:
593 #endif
594 if (bps == 16)
595 conv_func = change_sign16_le;
596 else if (bps == 32)
597 conv_func = change_sign32_le;
598 /* FALLTHROUGH */
599
600 case AUDIO_ENCODING_SLINEAR_LE:
601 case AUDIO_ENCODING_PCM16:
602 #if BYTE_ORDER == LITTLE_ENDIAN
603 case AUDIO_ENCODING_SLINEAR:
604 #endif
605 if (bps == 8)
606 conv_func = change_sign8;
607 fmt_pcm:
608 fmttag = WAVE_FORMAT_PCM;
609 fmtsz = 16;
610 align = channels * (bps / 8);
611 break;
612
613 default:
614 {
615 static int warned = 0;
616
617 if (warned == 0) {
618 const char *s = wav_enc_from_val(encoding);
619
620 if (s == NULL)
621 warnx("can not support encoding of %s", s);
622 else
623 warnx("can not support encoding of %d", encoding);
624 warned = 1;
625 }
626 }
627 format = AUDIO_FORMAT_NONE;
628 return (-1);
629 }
630
631 nchan = channels;
632 sps = sample_rate;
633
634 /* data length */
635 if (outfd == STDOUT_FILENO)
636 datalen = 0;
637 else if (total_size != -1)
638 datalen = total_size;
639 else
640 datalen = 0;
641
642 /* file length */
643 filelen = 4 + (8 + fmtsz) + (8 + datalen);
644 if (fmttag != WAVE_FORMAT_PCM)
645 filelen += 8 + factsz;
646
647 abps = (double)align*sample_rate / (double)1 + 0.5;
648
649 nsample = (datalen / bps) / sample_rate;
650
651 /*
652 * now we've calculated the info, write it out!
653 */
654 #define put32(x) do { \
655 u_int32_t _f; \
656 putle32(_f, (x)); \
657 memcpy(p, &_f, 4); \
658 } while (0)
659 #define put16(x) do { \
660 u_int16_t _f; \
661 putle16(_f, (x)); \
662 memcpy(p, &_f, 2); \
663 } while (0)
664 memcpy(p, riff, 4);
665 p += 4; /* 4 */
666 put32(filelen);
667 p += 4; /* 8 */
668 memcpy(p, wavefmt, 8);
669 p += 8; /* 16 */
670 put32(fmtsz);
671 p += 4; /* 20 */
672 put16(fmttag);
673 p += 2; /* 22 */
674 put16(nchan);
675 p += 2; /* 24 */
676 put32(sps);
677 p += 4; /* 28 */
678 put32(abps);
679 p += 4; /* 32 */
680 put16(align);
681 p += 2; /* 34 */
682 put16(bps);
683 p += 2; /* 36 */
684 /* NON PCM formats have an extended chunk; write it */
685 if (fmttag != WAVE_FORMAT_PCM) {
686 put16(extln);
687 p += 2; /* 38 */
688 memcpy(p, fact, 4);
689 p += 4; /* 42 */
690 put32(factsz);
691 p += 4; /* 46 */
692 put32(nsample);
693 p += 4; /* 50 */
694 }
695 memcpy(p, data, 4);
696 p += 4; /* 40/54 */
697 put32(datalen);
698 p += 4; /* 44/58 */
699 #undef put32
700 #undef put16
701
702 *hdrp = wavheaderbuf;
703 *lenp = (p - wavheaderbuf);
704
705 return 0;
706 }
707
708 void
709 write_header()
710 {
711 struct iovec iv[3];
712 int veclen, left, tlen;
713 void *hdr;
714 size_t hdrlen;
715
716 switch (format) {
717 case AUDIO_FORMAT_DEFAULT:
718 case AUDIO_FORMAT_SUN:
719 if (write_header_sun(&hdr, &hdrlen, &left) != 0)
720 return;
721 break;
722 case AUDIO_FORMAT_WAV:
723 if (write_header_wav(&hdr, &hdrlen, &left) != 0)
724 return;
725 break;
726 case AUDIO_FORMAT_NONE:
727 return;
728 default:
729 errx(1, "unknown audio format");
730 }
731
732 veclen = 0;
733 tlen = 0;
734
735 if (hdrlen != 0) {
736 iv[veclen].iov_base = hdr;
737 iv[veclen].iov_len = hdrlen;
738 tlen += iv[veclen++].iov_len;
739 }
740 if (header_info) {
741 iv[veclen].iov_base = header_info;
742 iv[veclen].iov_len = (int)strlen(header_info) + 1;
743 tlen += iv[veclen++].iov_len;
744 }
745 if (left) {
746 iv[veclen].iov_base = default_info;
747 iv[veclen].iov_len = left;
748 tlen += iv[veclen++].iov_len;
749 }
750
751 if (tlen == 0)
752 return;
753
754 if (writev(outfd, iv, veclen) != tlen)
755 err(1, "could not write audio header");
756 }
757
758 void
759 rewrite_header()
760 {
761
762 /* can't do this here! */
763 if (outfd == STDOUT_FILENO)
764 return;
765
766 if (lseek(outfd, SEEK_SET, 0) < 0)
767 err(1, "could not seek to start of file for header rewrite");
768 write_header();
769 }
770
771 void
772 usage()
773 {
774
775 fprintf(stderr, "Usage: %s [-afhqV] [options] {files ...|-}\n",
776 getprogname());
777 fprintf(stderr, "Options:\n\t"
778 "-b balance (0-63)\n\t"
779 "-c channels\n\t"
780 "-d audio device\n\t"
781 "-e encoding\n\t"
782 "-F format\n\t"
783 "-i header information\n\t"
784 "-m monitor volume\n\t"
785 "-P precision (4, 8, 16, 24, or 32 bits)\n\t"
786 "-p input port\n\t"
787 "-s sample rate\n\t"
788 "-t recording time\n\t"
789 "-v volume\n");
790 exit(EXIT_FAILURE);
791 }
792