xref: /netbsd-src/usr.bin/audio/record/record.c (revision e5548b402ae4c44fb816de42c7bba9581ce23ef5)
1 /*	$NetBSD: record.c,v 1.41 2005/07/13 10:57:11 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 1.41 2005/07/13 10:57:11 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 	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