xref: /titanic_41/usr/src/cmd/audio/utilities/filehdr.c (revision 7c478bd95313f5f23a4c958a745db2134aa03244)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 /*
30  * This file contains a set of Very Paranoid routines to convert
31  * audio file headers to in-core audio headers and vice versa.
32  *
33  * They are robust enough to handle any random file input without
34  * crashing miserably.  Of course, bad audio headers coming from
35  * the calling program can cause significant problems.
36  */
37 
38 #include <stdlib.h>
39 #include <memory.h>
40 #include <fcntl.h>
41 #include <errno.h>	/* needed for large file error checking */
42 #include <stdio.h>
43 #include <sys/types.h>
44 #include <sys/file.h>
45 #include <sys/stat.h>
46 #include <libintl.h>
47 #include <math.h>
48 
49 #include <libaudio_impl.h>	/* include other audio hdr's */
50 
51 /* Round up to a double boundary */
52 #define	ROUND_DBL(x)	(((x) + 7) & ~7)
53 
54 #define	HEADER_BUFFER		100
55 
56 #define	_MGET_(str)	(char *)dgettext(TEXT_DOMAIN, str)
57 
58 static int audio_encode_aiff(Audio_hdr *, unsigned char *, unsigned int *);
59 static int audio_encode_au(Audio_hdr *, char *, unsigned int,
60 	unsigned char *, unsigned int *);
61 static int audio_encode_wav(Audio_hdr *, unsigned char *, unsigned int *);
62 static double convert_from_ieee_extended(unsigned char *);
63 static void convert_to_ieee_extended(double, unsigned char *);
64 
65 /*
66  * Write an audio file header to an output stream.
67  *
68  * The file header is encoded from the supplied Audio_hdr structure.
69  * If 'infop' is not NULL, it is the address of a buffer containing 'info'
70  * data.  'ilen' specifies the size of this buffer.
71  * The entire file header will be zero-padded to a double-word boundary.
72  *
73  * Note that the file header is stored on-disk in big-endian format,
74  * regardless of the machine type.
75  *
76  * Note also that the output file descriptor must not have been set up
77  * non-blocking i/o.  If non-blocking behavior is desired, set this
78  * flag after writing the file header.
79  */
80 int
audio_write_filehdr(int fd,Audio_hdr * hdrp,int file_type,char * infop,unsigned int ilen)81 audio_write_filehdr(int fd, Audio_hdr *hdrp, int file_type, char *infop,
82 	unsigned int ilen)
83 					/* file descriptor */
84 					/* audio header */
85 					/* audio header type */
86 					/* info buffer pointer */
87 					/* buffer size */
88 {
89 	int		err;
90 	unsigned	blen;
91 	unsigned char	*buf;		/* temporary buffer */
92 
93 	/* create tmp buf for the encoding routines to work with */
94 	blen = HEADER_BUFFER + (infop ? ilen : 0) + 4;
95 	blen = ROUND_DBL(blen);
96 
97 	if (!(buf = (unsigned char *)calloc(1, blen))) {
98 		return (AUDIO_UNIXERROR);
99 	}
100 
101 	switch (file_type) {
102 	case FILE_AU:
103 		err = audio_encode_au(hdrp, infop, ilen, buf, &blen);
104 		break;
105 	case FILE_WAV:
106 		err = audio_encode_wav(hdrp, buf, &blen);
107 		break;
108 	case FILE_AIFF:
109 		err = audio_encode_aiff(hdrp, buf, &blen);
110 		break;
111 	default:
112 		return (AUDIO_ERR_BADFILETYPE);
113 	}
114 
115 	if (err != AUDIO_SUCCESS) {
116 		return (err);
117 	}
118 
119 	/* Write and free the holding buffer */
120 	err = write(fd, (char *)buf, (int)blen);
121 	(void) free((char *)buf);
122 
123 	if (err != blen)
124 		return ((err < 0) ? AUDIO_UNIXERROR : AUDIO_ERR_BADFILEHDR);
125 
126 	return (AUDIO_SUCCESS);
127 
128 }
129 
130 /*
131  * Rewrite the aiff header chunk length and the data chunk length fields.
132  */
133 static int
audio_rewrite_aiff_filesize(int fd,unsigned int size,unsigned int channels,unsigned int bytes_per_sample)134 audio_rewrite_aiff_filesize(int fd, unsigned int size, unsigned int channels,
135 	unsigned int bytes_per_sample)
136 {
137 	unsigned int	offset;
138 	unsigned int	tmp_uint;
139 	unsigned int	tmp_uint2;
140 	unsigned int	total_size;
141 
142 	/* first fix aiff_hdr_size */
143 	total_size = size + sizeof (aiff_hdr_chunk_t) +
144 	    AUDIO_AIFF_COMM_CHUNK_SIZE + sizeof (aiff_ssnd_chunk_t);
145 	tmp_uint = total_size - (2 * sizeof (int));
146 	AUDIO_AIFF_HOST2FILE_INT(&tmp_uint, &tmp_uint2);
147 	offset = sizeof (int);
148 	if (lseek(fd, offset, SEEK_SET) < 0) {
149 		return (AUDIO_ERR_NOEFFECT);
150 	}
151 	if (write(fd, &tmp_uint2, sizeof (tmp_uint2)) != sizeof (tmp_uint2)) {
152 		return (AUDIO_ERR_NOEFFECT);
153 	}
154 
155 	/* fix the frame count */
156 	tmp_uint = size / channels / bytes_per_sample;
157 	AUDIO_AIFF_HOST2FILE_INT(&tmp_uint, &tmp_uint2);
158 	offset = sizeof (aiff_hdr_chunk_t) + (2 * sizeof (int)) +
159 	    sizeof (short);
160 	if (lseek(fd, offset, SEEK_SET) < 0) {
161 		return (AUDIO_ERR_NOEFFECT);
162 	}
163 	if (write(fd, &tmp_uint2, sizeof (tmp_uint2)) != sizeof (tmp_uint2)) {
164 		return (AUDIO_ERR_NOEFFECT);
165 	}
166 
167 	/* fix the data size */
168 	tmp_uint = size + sizeof (aiff_ssnd_chunk_t) - (2 * sizeof (int));
169 	AUDIO_AIFF_HOST2FILE_INT(&tmp_uint, &tmp_uint2);
170 	offset = sizeof (aiff_hdr_chunk_t) + AUDIO_AIFF_COMM_CHUNK_SIZE +
171 	    sizeof (int);
172 	if (lseek(fd, offset, SEEK_SET) < 0) {
173 		return (AUDIO_ERR_NOEFFECT);
174 	}
175 	if (write(fd, &tmp_uint2, sizeof (tmp_uint2)) != sizeof (tmp_uint2)) {
176 		return (AUDIO_ERR_NOEFFECT);
177 	}
178 
179 	return (AUDIO_SUCCESS);
180 
181 }
182 
183 /*
184  * Rewrite the data size field for the .au file format. Rewrite the audio
185  * file header au_data_size field with the supplied value. Otherwise,
186  * return AUDIO_ERR_NOEFFECT.
187  */
188 static int
audio_rewrite_au_filesize(int fd,unsigned int size)189 audio_rewrite_au_filesize(int fd, unsigned int size)
190 {
191 	au_filehdr_t	fhdr;
192 	int		err;
193 	int		data;
194 	int		offset;
195 
196 	/* seek to the position of the au_data_size member */
197 	offset = (char *)&fhdr.au_data_size - (char *)&fhdr;
198 	if (lseek(fd, offset, SEEK_SET) < 0) {
199 		return (AUDIO_ERR_NOEFFECT);
200 	}
201 
202 	/* Encode the 32-bit integer header field */
203 	AUDIO_AU_HOST2FILE(&size, &data);
204 
205 	/* Write the data */
206 	err = write(fd, (char *)&data, sizeof (fhdr.au_data_size));
207 	if (err != sizeof (fhdr.au_data_size))
208 		return ((err < 0) ? AUDIO_UNIXERROR : AUDIO_ERR_BADFILEHDR);
209 
210 	return (AUDIO_SUCCESS);
211 
212 }
213 
214 /*
215  * Rewrite the riff header chunk length and the data chunk length fields.
216  */
217 static int
audio_rewrite_wav_filesize(int fd,unsigned int size)218 audio_rewrite_wav_filesize(int fd, unsigned int size)
219 {
220 	wav_filehdr_t	fhdr;
221 	int		calc_size;
222 	int		err;
223 	int		data;
224 	int		offset;
225 
226 	/* seek to the position of the riff header chunk length */
227 	calc_size = size + sizeof (fhdr) - sizeof (fhdr.wav_riff_ID) -
228 	    sizeof (fhdr.wav_riff_size);
229 	AUDIO_WAV_HOST2FILE_INT(&calc_size, &data);
230 	offset = (char *)&fhdr.wav_riff_size - (char *)&fhdr;
231 	if (lseek(fd, offset, SEEK_SET) < 0) {
232 		return (AUDIO_ERR_NOEFFECT);
233 	}
234 
235 	/* Write the data */
236 	err = write(fd, (char *)&data, sizeof (fhdr.wav_riff_size));
237 	if (err != sizeof (fhdr.wav_riff_size))
238 		return ((err < 0) ? AUDIO_UNIXERROR : AUDIO_ERR_BADFILEHDR);
239 
240 	/* now seek to the position of the data chunk length */
241 	AUDIO_WAV_HOST2FILE_INT(&size, &data);
242 	offset = (char *)&fhdr.wav_data_size - (char *)&fhdr;
243 	if (lseek(fd, offset, SEEK_SET) < 0) {
244 		return (AUDIO_ERR_NOEFFECT);
245 	}
246 
247 	/* Write the data */
248 	err = write(fd, (char *)&data, sizeof (fhdr.wav_data_size));
249 	if (err != sizeof (fhdr.wav_data_size))
250 		return ((err < 0) ? AUDIO_UNIXERROR : AUDIO_ERR_BADFILEHDR);
251 
252 	return (AUDIO_SUCCESS);
253 
254 }
255 
256 /*
257  * Rewrite the data size field of an audio header to the output stream if
258  * the output file is capable of seeking.
259  */
260 int
audio_rewrite_filesize(int fd,int file_type,unsigned int size,unsigned int channels,unsigned int bytes_per_sample)261 audio_rewrite_filesize(int fd, int file_type, unsigned int size,
262 	unsigned int channels, unsigned int bytes_per_sample)
263 					/* file descriptor */
264 					/* audio file type */
265 					/* new data size */
266 					/* number of channels */
267 					/* number of bytes per sample */
268 {
269 	int		fcntl_err;
270 
271 	/* Can we seek back in this file and write without appending? */
272 	fcntl_err = fcntl(fd, F_GETFL, 0);
273 	if ((fcntl_err < 0) && ((errno == EOVERFLOW) || (errno == EINVAL))) {
274 		/* Large file encountered (probably) */
275 		perror("fcntl");
276 		exit(1);
277 	} else if ((lseek(fd, (off_t)0, SEEK_SET) < 0) ||
278 		    (fcntl_err & FAPPEND)) {
279 		return (AUDIO_ERR_NOEFFECT);
280 	}
281 
282 	switch (file_type) {
283 	case FILE_AU:
284 		return (audio_rewrite_au_filesize(fd, size));
285 	case FILE_WAV:
286 		return (audio_rewrite_wav_filesize(fd, size));
287 	case FILE_AIFF:
288 		return (audio_rewrite_aiff_filesize(fd, size, channels,
289 		    bytes_per_sample));
290 	default:
291 		return (AUDIO_ERR_BADFILETYPE);
292 	}
293 }
294 
295 
296 /*
297  * Decode an audio file header from an input stream.
298  *
299  * The file header is decoded into the supplied Audio_hdr structure, regardless
300  * of the file format. Thus .wav and .aiff files look like .au files once the
301  * header is decoded.
302  *
303  * If 'infop' is not NULL, it is the address of a buffer to which the
304  * 'info' portion of the file header will be copied.  'ilen' specifies
305  * the maximum number of bytes to copy.  The buffer will be NULL-terminated,
306  * even if it means over-writing the last byte.
307  *
308  * Note that the .au file header is stored on-disk in big-endian format,
309  * regardless of the machine type.  This may not have been true if
310  * the file was written on a non-Sun machine.  For now, such
311  * files will appear invalid.
312  *
313  * Note also that the input file descriptor must not have been set up
314  * non-blocking i/o.  If non-blocking behavior is desired, set this
315  * flag after reading the file header.
316  */
317 int
audio_read_filehdr(int fd,Audio_hdr * hdrp,int * file_type,char * infop,unsigned int ilen)318 audio_read_filehdr(int fd, Audio_hdr *hdrp, int *file_type, char *infop,
319 	unsigned int ilen)
320 					/* input file descriptor */
321 					/* output audio header */
322 					/* audio file type */
323 					/* info buffer pointer */
324 					/* buffer size */
325 {
326 	int		err;
327 	int		dsize;
328 	int		isize;
329 	unsigned	resid;
330 	unsigned char	buf[HEADER_BUFFER];
331 	struct stat	st;
332 
333 	/* decode the file header and fill in the hdrp structure */
334 	if ((err = audio_decode_filehdr(fd, buf, file_type, hdrp, &isize)) !=
335 	    AUDIO_SUCCESS) {
336 		goto checkerror;
337 	}
338 
339 	/* Stat the file, to determine if it is a regular file. */
340 	err = fstat(fd, &st);
341 	if (err < 0) {
342 		return (AUDIO_UNIXERROR);
343 	}
344 
345 	/*
346 	 * If au_data_size is not indeterminate (i.e., this isn't a pipe),
347 	 * try to validate the au_offset and au_data_size.
348 	 */
349 	if (*file_type == FILE_AU && hdrp->data_size != AUDIO_UNKNOWN_SIZE) {
350 		/* Only trust the size for regular files */
351 		if (S_ISREG(st.st_mode)) {
352 			dsize = isize + hdrp->data_size + sizeof (au_filehdr_t);
353 			if (st.st_size < dsize) {
354 				(void) fprintf(stderr,
355 				    _MGET_("Warning: More audio data "
356 				    "than the file header specifies\n"));
357 			} else if (st.st_size > dsize) {
358 				(void) fprintf(stderr,
359 				    _MGET_("Warning: Less audio data "
360 				    "than the file header specifies\n"));
361 			}
362 		}
363 	}
364 
365 	resid = isize;
366 	/*
367 	 * Deal with extra header data.
368 	 */
369 	if ((infop != NULL) && (ilen != 0)) {
370 		/*
371 		 * If infop is non-NULL, try to read in the info data
372 		 */
373 		if (isize > ilen)
374 			isize = ilen;
375 		err = read(fd, infop, (int)isize);
376 		if (err != isize)
377 			goto checkerror;
378 
379 		/* Zero any residual bytes in the text buffer */
380 		if (isize < ilen)
381 			(void) memset(&infop[isize], '\0',
382 				    (int)(ilen - isize));
383 		else
384 			infop[ilen - 1] = '\0';	/* zero-terminate */
385 
386 		resid -= err;		/* subtract the amount read */
387 	}
388 
389 	/*
390 	 * If we truncated the info, seek or read data until info size
391 	 * is satisfied.  If regular file, seek nearly to end and check
392 	 * for eof.
393 	 */
394 	if (resid != 0) {
395 		if (S_ISREG(st.st_mode)) {
396 			err = lseek(fd, (off_t)(resid - 1), SEEK_CUR);
397 			if ((err < 0) ||
398 			    ((err = read(fd, (char *)buf, 1)) != 1))
399 				goto checkerror;
400 		} else while (resid != 0) {
401 			char	junk[8192];	/* temporary buffer */
402 
403 			isize = (resid > sizeof (junk)) ?
404 			    sizeof (junk) : resid;
405 			err = read(fd, junk, isize);
406 			if (err != isize)
407 				goto checkerror;
408 			resid -= err;
409 		}
410 	}
411 
412 	return (AUDIO_SUCCESS);
413 
414 checkerror:
415 	if ((err < 0) && (errno == EOVERFLOW)) {
416 		perror("read");
417 		exit(1);
418 	} else {
419 		return ((err < 0) ? AUDIO_UNIXERROR : AUDIO_ERR_BADFILEHDR);
420 	}
421 	return (AUDIO_SUCCESS);
422 }
423 
424 /*
425  * Return TRUE if the named file is an audio file.  Else, return FALSE.
426  */
427 int
audio_isaudiofile(char * name)428 audio_isaudiofile(char *name)
429 {
430 	int		fd;
431 	int		err;
432 	int		file_type;	/* ignored */
433 	int		isize;
434 	Audio_hdr	hdr;
435 	unsigned char	buf[sizeof (au_filehdr_t)];
436 
437 	/* Open the file (set O_NONBLOCK in case the name refers to a device) */
438 	fd = open(name, O_RDONLY | O_NONBLOCK);
439 	if (fd < 0) {
440 		if (errno == EOVERFLOW) {
441 			perror("open");
442 			exit(1);
443 		} else {
444 			return (FALSE);
445 		}
446 	}
447 
448 	/* Read the header (but not the text info). */
449 	err = read(fd, (char *)buf, sizeof (buf));
450 	if (err < 0) {
451 		if (errno == EOVERFLOW) {
452 			perror("open");
453 			exit(1);
454 		} else {
455 			return (FALSE);
456 		}
457 	}
458 	(void) close(fd);
459 
460 	if ((err == sizeof (buf)) &&
461 	    (audio_decode_filehdr(fd, buf, &file_type, &hdr, &isize) ==
462 	    AUDIO_SUCCESS)) {
463 		return (hdr.encoding);
464 	} else {
465 		return (FALSE);
466 	}
467 }
468 
469 /*
470  * audio_endian()
471  *
472  * This routine tests the magic number at the head of a buffer
473  * containing the file header.  The first thing in the header
474  * should be the magic number.
475  */
476 static int
audio_endian(unsigned char * buf,int * file_type)477 audio_endian(unsigned char *buf, int *file_type)
478 {
479 	unsigned int	magic1;
480 	unsigned int	magic2;
481 
482 	/* put the buffer into an int that is aligned properly */
483 	(void) memcpy(&magic1, buf, sizeof (magic1));
484 
485 	magic2 = magic1;
486 	SWABI(magic2);
487 
488 	if (magic1 == AUDIO_AU_FILE_MAGIC || magic2 == AUDIO_AU_FILE_MAGIC) {
489 		*file_type = FILE_AU;
490 		return (AUDIO_ENDIAN_BIG);
491 	} else if (magic1 == AUDIO_WAV_RIFF_ID || magic2 == AUDIO_WAV_RIFF_ID) {
492 		*file_type = FILE_WAV;
493 		return (AUDIO_ENDIAN_SMALL);
494 	} else if (magic1 == AUDIO_AIFF_HDR_CHUNK_ID ||
495 	    magic2 == AUDIO_AIFF_HDR_CHUNK_ID) {
496 		*file_type = FILE_AIFF;
497 		return (AUDIO_ENDIAN_BIG);
498 	}
499 
500 	return (AUDIO_ENDIAN_UNKNOWN);
501 }
502 
503 /*
504  * Decode an aiff file header. Unlike .au and .wav, we have to process
505  * by chunk.
506  */
507 static int
decode_aiff(int fd,unsigned char * buf,Audio_hdr * hdrp,int * isize)508 decode_aiff(int fd, unsigned char *buf, Audio_hdr *hdrp, int *isize)
509 {
510 	aiff_hdr_chunk_t	hdr_chunk;
511 	aiff_comm_chunk_t	comm_chunk;
512 	aiff_ssnd_chunk_t	ssnd_chunk;
513 	uint32_t		ID;
514 	uint32_t		size;
515 	uint32_t		tmp;
516 	int			data_type;
517 	int			hdr_sizes;
518 	int			sr;
519 	short			bits_per_sample;
520 	short			channels;
521 
522 	/* we've read in 4 bytes, read in the rest of the wav header */
523 	size = sizeof (hdr_chunk) - sizeof (hdr_chunk.aiff_hdr_ID);
524 
525 	/* read in the rest of the header */
526 	if (read(fd, &hdr_chunk.aiff_hdr_size, size) != size) {
527 		return (AUDIO_UNIXERROR);
528 	}
529 
530 	/* see which kind of audio file we have */
531 	AUDIO_AIFF_FILE2HOST_INT(&hdr_chunk.aiff_hdr_data_type, &data_type);
532 	if (data_type != AUDIO_AIFF_HDR_FORM_AIFF) {
533 		/* we can't play this version of a .aiff file */
534 		return (AUDIO_ERR_BADFILEHDR);
535 	}
536 
537 	hdr_sizes = sizeof (hdr_chunk);
538 
539 	/*
540 	 * We don't know what the chunk order will be, so read each, getting
541 	 * the data we need from each. Eventually we'll get to the end of
542 	 * the file, in which case we should have all of the info on the
543 	 * file that we need. We then lseek() back to the data to play.
544 	 *
545 	 * We start each loop by reading the chunk ID.
546 	 */
547 	while (read(fd, &tmp, sizeof (tmp)) == sizeof (tmp)) {
548 		AUDIO_AIFF_FILE2HOST_INT(&tmp, &ID);
549 		switch (ID) {
550 		case AUDIO_AIFF_COMM_ID:
551 			/* read in the rest of the COMM chunk */
552 			size = AUDIO_AIFF_COMM_CHUNK_SIZE -
553 			    sizeof (comm_chunk.aiff_comm_ID);
554 			if (read(fd, &comm_chunk.aiff_comm_size, size) !=
555 			    size) {
556 				return (AUDIO_UNIXERROR);
557 			}
558 
559 			sr = convert_from_ieee_extended(
560 			    comm_chunk.aiff_comm_sample_rate);
561 
562 			hdr_sizes += AUDIO_AIFF_COMM_CHUNK_SIZE;
563 
564 			break;
565 		case AUDIO_AIFF_SSND_ID:
566 			/* read in the rest of the INST chunk */
567 			size = sizeof (ssnd_chunk) -
568 			    sizeof (ssnd_chunk.aiff_ssnd_ID);
569 			if (read(fd, &ssnd_chunk.aiff_ssnd_size, size) !=
570 			    size) {
571 				return (AUDIO_UNIXERROR);
572 			}
573 
574 			/*
575 			 * This has to be the last chunk because the audio data
576 			 * follows. So we should have all we need to tell the
577 			 * app the format information.
578 			 */
579 			hdrp->sample_rate = sr;
580 
581 			AUDIO_AIFF_FILE2HOST_SHORT(
582 			    &comm_chunk.aiff_comm_channels,
583 			    &channels);
584 			/* use channels to convert from short to int */
585 			hdrp->channels = channels;
586 
587 			AUDIO_AIFF_FILE2HOST_SHORT(
588 			    &comm_chunk.aiff_comm_sample_size,
589 			    &bits_per_sample);
590 			switch (bits_per_sample) {
591 			case AUDIO_AIFF_COMM_8_BIT_SAMPLE_SIZE:
592 				hdrp->encoding = AUDIO_AU_ENCODING_LINEAR_8;
593 				break;
594 			case AUDIO_AIFF_COMM_16_BIT_SAMPLE_SIZE:
595 				hdrp->encoding = AUDIO_AU_ENCODING_LINEAR_16;
596 				break;
597 			default:
598 				return (AUDIO_ERR_BADFILEHDR);
599 			}
600 
601 			AUDIO_AIFF_FILE2HOST_INT(&ssnd_chunk.aiff_ssnd_size,
602 			    &size);
603 			size -= sizeof (ssnd_chunk.aiff_ssnd_offset) +
604 			    sizeof (ssnd_chunk.aiff_ssnd_block_size);
605 			hdrp->data_size = size;
606 
607 			hdr_sizes += sizeof (ssnd_chunk);
608 
609 			*isize = hdr_sizes - sizeof (au_filehdr_t);
610 
611 			return (AUDIO_SUCCESS);
612 		default:
613 			/*
614 			 * Unknown chunk. Read the size, which is right after
615 			 * the ID. Then seek past it to get to the next chunk.
616 			 */
617 			if (read(fd, &size, sizeof (size)) != sizeof (size)) {
618 				return (AUDIO_UNIXERROR);
619 			}
620 
621 			if (lseek(fd, size, SEEK_CUR) < 0) {
622 				return (AUDIO_UNIXERROR);
623 			}
624 			break;
625 		}
626 	}
627 
628 	return (AUDIO_SUCCESS);
629 
630 }	/* decode_aiff() */
631 
632 /*
633  * Decode an au file header.
634  */
635 static int
decode_au(int fd,unsigned char * buf,Audio_hdr * hdrp,int * isize,boolean_t read_info)636 decode_au(int fd, unsigned char *buf, Audio_hdr *hdrp, int *isize,
637     boolean_t read_info)
638 {
639 	au_filehdr_t	fhdr;
640 	int		offset;
641 	int		size;
642 
643 	if (read_info) {
644 		/* read in the rest of the au header */
645 		size = sizeof (fhdr) - sizeof (int);
646 		(void) lseek(fd, (off_t)4, SEEK_SET);
647 		if (read(fd, &buf[sizeof (int)], size) != size) {
648 
649 			return (AUDIO_UNIXERROR);
650 		}
651 	}
652 
653 	/* put the buffer into a structure that is aligned properly */
654 	(void) memcpy(&fhdr, buf, sizeof (fhdr));
655 
656 	/* Decode the 32-bit integer header fields. */
657 	AUDIO_AU_FILE2HOST(&fhdr.au_offset, &offset);
658 	AUDIO_AU_FILE2HOST(&fhdr.au_data_size, &hdrp->data_size);
659 	AUDIO_AU_FILE2HOST(&fhdr.au_encoding, &hdrp->encoding);
660 	AUDIO_AU_FILE2HOST(&fhdr.au_sample_rate, &hdrp->sample_rate);
661 	AUDIO_AU_FILE2HOST(&fhdr.au_channels, &hdrp->channels);
662 
663 	/* Set the info field size (ie, number of bytes left before data). */
664 	*isize = offset - sizeof (au_filehdr_t);
665 
666 	return (AUDIO_SUCCESS);
667 
668 }	/* decode_au() */
669 
670 /*
671  * Decode a wav file header.
672  *
673  * .wav files are stored on-disk in little-endian format.
674  */
675 static int
decode_wav(int fd,unsigned char * buf,Audio_hdr * hdrp,int * isize)676 decode_wav(int fd, unsigned char *buf, Audio_hdr *hdrp, int *isize)
677 {
678 	wav_filehdr_t	fhdr;
679 	uint32_t	ID;
680 	uint32_t	size;
681 	short		bits_per_sample;
682 	short		encoding;
683 
684 	/* we've read in 4 bytes, read in the rest of the wav header */
685 	size = sizeof (fhdr) - sizeof (int);
686 
687 	/* read in the rest of the header */
688 	if (read(fd, &buf[sizeof (int)], size) != size) {
689 		return (AUDIO_UNIXERROR);
690 	}
691 
692 	/* put the buffer into a structure that is aligned properly */
693 	(void) memcpy(&fhdr, buf, sizeof (fhdr));
694 
695 	/* make sure we have the correct RIFF type */
696 	AUDIO_WAV_FILE2HOST_INT(&fhdr.wav_type_ID, &ID);
697 	if (ID != AUDIO_WAV_TYPE_ID) {
698 		/* not a wave file */
699 		return (AUDIO_ERR_BADFILEHDR);
700 	}
701 
702 	/* decode the fields */
703 	AUDIO_WAV_FILE2HOST_INT(&fhdr.wav_fmt_ID, &ID);
704 	if (ID != AUDIO_WAV_FORMAT_ID) {
705 		/* mangled format */
706 		return (AUDIO_ERR_BADFILEHDR);
707 	}
708 
709 	AUDIO_WAV_FILE2HOST_SHORT(&fhdr.wav_fmt_encoding, &encoding);
710 	AUDIO_WAV_FILE2HOST_SHORT(&fhdr.wav_fmt_channels, &hdrp->channels);
711 	AUDIO_WAV_FILE2HOST_INT(&fhdr.wav_fmt_sample_rate, &hdrp->sample_rate);
712 	AUDIO_WAV_FILE2HOST_SHORT(&fhdr.wav_fmt_bits_per_sample,
713 	    &bits_per_sample);
714 
715 	/* convert .wav encodings to .au encodings */
716 	switch (encoding) {
717 	case AUDIO_WAV_FMT_ENCODING_PCM:
718 		switch (bits_per_sample) {
719 		case AUDIO_WAV_FMT_BITS_PER_SAMPLE_8_BITS:
720 			hdrp->encoding = AUDIO_AU_ENCODING_LINEAR_8;
721 			break;
722 		case AUDIO_WAV_FMT_BITS_PER_SAMPLE_16_BITS:
723 			hdrp->encoding = AUDIO_AU_ENCODING_LINEAR_16;
724 			break;
725 		default:
726 			return (AUDIO_ERR_BADFILEHDR);
727 		}
728 		break;
729 	case AUDIO_WAV_FMT_ENCODING_ALAW:
730 		hdrp->encoding = AUDIO_AU_ENCODING_ALAW;
731 		break;
732 	case AUDIO_WAV_FMT_ENCODING_MULAW:
733 		hdrp->encoding = AUDIO_AU_ENCODING_ULAW;
734 		break;
735 	default:
736 		return (AUDIO_ERR_BADFILEHDR);
737 	}
738 
739 	AUDIO_WAV_FILE2HOST_INT(&fhdr.wav_data_size, &hdrp->data_size);
740 
741 	*isize = sizeof (wav_filehdr_t) - sizeof (au_filehdr_t);
742 
743 	return (AUDIO_SUCCESS);
744 
745 }	/* decode_wav() */
746 
747 /*
748  * Try to decode buffer containing an audio file header into an audio header.
749  */
750 int
audio_decode_filehdr(int fd,unsigned char * buf,int * file_type,Audio_hdr * hdrp,int * isize)751 audio_decode_filehdr(int fd, unsigned char *buf, int *file_type,
752 	Audio_hdr *hdrp, int *isize)
753 					/* file descriptor */
754 					/* buffer address */
755 					/* audio file type */
756 					/* output audio header */
757 					/* output size of info */
758 {
759 	int		err;
760 	struct stat	fd_stat;
761 	boolean_t	read_info;
762 
763 	/* Test for .au first */
764 	hdrp->endian = audio_endian(buf, file_type);
765 
766 	/*
767 	 * When cat'ing a file, audioconvert will read the whole header
768 	 * trying to figure out the file. audioplay however, does not.
769 	 * Hence we check if this is a pipe and do not attempt to read
770 	 * any more header info if the file type is already known.
771 	 * Otherwise we overwrite the header data already in the buffer.
772 	 */
773 	if (fstat(fd, &fd_stat) < 0) {
774 		return (AUDIO_ERR_BADFILEHDR);
775 	}
776 	if (S_ISFIFO(fd_stat.st_mode) && (*file_type == FILE_AU)) {
777 		read_info = B_FALSE;
778 	} else {
779 		/*
780 		 * Not an au file, or file type unknown. Reread the header's
781 		 * magic number. Fortunately this is always an int.
782 		 */
783 		(void) lseek(fd, (off_t)0, SEEK_SET);
784 		err = read(fd, (char *)buf, sizeof (int));
785 		read_info = B_TRUE;
786 
787 		/* test the magic number to determine the endian */
788 		if ((hdrp->endian = audio_endian(buf, file_type)) ==
789 		    AUDIO_ENDIAN_UNKNOWN) {
790 
791 			return (AUDIO_ERR_BADFILEHDR);
792 		}
793 	}
794 
795 	/* decode the different file types, putting the data into hdrp */
796 	switch (*file_type) {
797 	case FILE_AU:
798 		if ((err = decode_au(fd, buf, hdrp, isize, read_info)) !=
799 		    AUDIO_SUCCESS) {
800 			return (err);
801 		}
802 		break;
803 	case FILE_WAV:
804 		if ((err = decode_wav(fd, buf, hdrp, isize)) != AUDIO_SUCCESS) {
805 			return (err);
806 		}
807 		break;
808 	case FILE_AIFF:
809 		if ((err = decode_aiff(fd, buf, hdrp, isize)) !=
810 		    AUDIO_SUCCESS) {
811 			return (err);
812 		}
813 		break;
814 	default:
815 		return (AUDIO_ERR_BADFILEHDR);
816 	}
817 
818 	/* Convert from file format info to audio format info */
819 	switch (hdrp->encoding) {
820 	case AUDIO_AU_ENCODING_ULAW:
821 		hdrp->encoding = AUDIO_ENCODING_ULAW;
822 		hdrp->bytes_per_unit = 1;
823 		hdrp->samples_per_unit = 1;
824 		break;
825 	case AUDIO_AU_ENCODING_ALAW:
826 		hdrp->encoding = AUDIO_ENCODING_ALAW;
827 		hdrp->bytes_per_unit = 1;
828 		hdrp->samples_per_unit = 1;
829 		break;
830 	case AUDIO_AU_ENCODING_LINEAR_8:
831 		if (*file_type == FILE_WAV) {
832 			hdrp->encoding = AUDIO_ENCODING_LINEAR8;
833 		} else {
834 			hdrp->encoding = AUDIO_ENCODING_LINEAR;
835 		}
836 		hdrp->bytes_per_unit = 1;
837 		hdrp->samples_per_unit = 1;
838 		break;
839 	case AUDIO_AU_ENCODING_LINEAR_16:
840 		hdrp->encoding = AUDIO_ENCODING_LINEAR;
841 		hdrp->bytes_per_unit = 2;
842 		hdrp->samples_per_unit = 1;
843 		break;
844 	case AUDIO_AU_ENCODING_LINEAR_24:
845 		hdrp->encoding = AUDIO_ENCODING_LINEAR;
846 		hdrp->bytes_per_unit = 3;
847 		hdrp->samples_per_unit = 1;
848 		break;
849 	case AUDIO_AU_ENCODING_LINEAR_32:
850 		hdrp->encoding = AUDIO_ENCODING_LINEAR;
851 		hdrp->bytes_per_unit = 4;
852 		hdrp->samples_per_unit = 1;
853 		break;
854 	case AUDIO_AU_ENCODING_FLOAT:
855 		hdrp->encoding = AUDIO_ENCODING_FLOAT;
856 		hdrp->bytes_per_unit = 4;
857 		hdrp->samples_per_unit = 1;
858 		break;
859 	case AUDIO_AU_ENCODING_DOUBLE:
860 		hdrp->encoding = AUDIO_ENCODING_FLOAT;
861 		hdrp->bytes_per_unit = 8;
862 		hdrp->samples_per_unit = 1;
863 		break;
864 	case AUDIO_AU_ENCODING_ADPCM_G721:
865 		hdrp->encoding = AUDIO_ENCODING_G721;
866 		hdrp->bytes_per_unit = 1;
867 		hdrp->samples_per_unit = 2;
868 		break;
869 	case AUDIO_AU_ENCODING_ADPCM_G723_3:
870 		hdrp->encoding = AUDIO_ENCODING_G723;
871 		hdrp->bytes_per_unit = 3;
872 		hdrp->samples_per_unit = 8;
873 		break;
874 	case AUDIO_AU_ENCODING_ADPCM_G723_5:
875 		hdrp->encoding = AUDIO_ENCODING_G723;
876 		hdrp->bytes_per_unit = 5;
877 		hdrp->samples_per_unit = 8;
878 		break;
879 
880 	default:
881 		return (AUDIO_ERR_BADFILEHDR);
882 	}
883 	return (AUDIO_SUCCESS);
884 }
885 
886 /*
887  * Encode a .aiff file header from the supplied Audio_hdr structure and
888  * store in the supplied char* buffer. blen is the size of the buffer to
889  * store the header in. Unlike .au and .wav we can't cast to a data structure.
890  * We have to build it one chunk at a time.
891  *
892  * NOTE: .aiff doesn't support unsigned 8-bit linear PCM.
893  */
894 static int
audio_encode_aiff(Audio_hdr * hdrp,unsigned char * buf,unsigned int * blen)895 audio_encode_aiff(Audio_hdr *hdrp, unsigned char *buf, unsigned int *blen)
896 					/* audio header */
897 					/* output buffer */
898 					/* output buffer size */
899 {
900 	aiff_comm_chunk_t	comm_chunk;
901 	aiff_hdr_chunk_t	hdr_chunk;
902 	aiff_ssnd_chunk_t	ssnd_chunk;
903 	uint32_t		tmp_uint;
904 	uint32_t		tmp_uint2;
905 	int			buf_size = 0;
906 	int			encoding;
907 	uint16_t		tmp_ushort;
908 
909 	/* the only encoding we support for .aiff is signed linear PCM */
910 	if (hdrp->encoding != AUDIO_ENCODING_LINEAR) {
911 		return (AUDIO_ERR_ENCODING);
912 	}
913 
914 	/* build the header chunk */
915 	tmp_uint = AUDIO_AIFF_HDR_CHUNK_ID;
916 	AUDIO_AIFF_HOST2FILE_INT(&tmp_uint, &hdr_chunk.aiff_hdr_ID);
917 	/* needs to be fixed when closed */
918 	tmp_uint = AUDIO_AIFF_UNKNOWN_SIZE;
919 	AUDIO_AIFF_HOST2FILE_INT(&tmp_uint, &hdr_chunk.aiff_hdr_size);
920 	tmp_uint = AUDIO_AIFF_HDR_FORM_AIFF;
921 	AUDIO_AIFF_HOST2FILE_INT(&tmp_uint, &hdr_chunk.aiff_hdr_data_type);
922 	(void) memcpy(&buf[buf_size], &hdr_chunk, sizeof (hdr_chunk));
923 	buf_size += sizeof (hdr_chunk);
924 
925 	/* build the COMM chunk */
926 	tmp_uint = AUDIO_AIFF_COMM_ID;
927 	AUDIO_AIFF_HOST2FILE_INT(&tmp_uint, &comm_chunk.aiff_comm_ID);
928 	tmp_uint = AUDIO_AIFF_COMM_SIZE;
929 	AUDIO_AIFF_HOST2FILE_INT(&tmp_uint, &comm_chunk.aiff_comm_size);
930 	tmp_ushort = hdrp->channels;
931 	AUDIO_AIFF_HOST2FILE_SHORT(&tmp_ushort, &comm_chunk.aiff_comm_channels);
932 	/* needs to be fixed when closed */
933 	tmp_uint = AUDIO_AIFF_UNKNOWN_SIZE;
934 	AUDIO_AIFF_HOST2FILE_INT(&tmp_uint, &tmp_uint2);
935 	AUDIO_AIFF_COMM_INT2FRAMES(comm_chunk.aiff_comm_frames, tmp_uint2);
936 	tmp_ushort = hdrp->bytes_per_unit * 8;
937 	AUDIO_AIFF_HOST2FILE_SHORT(&tmp_ushort,
938 	    &comm_chunk.aiff_comm_sample_size);
939 	convert_to_ieee_extended((double)hdrp->sample_rate,
940 	    comm_chunk.aiff_comm_sample_rate);
941 	(void) memcpy(&buf[buf_size], &comm_chunk, AUDIO_AIFF_COMM_CHUNK_SIZE);
942 	buf_size += AUDIO_AIFF_COMM_CHUNK_SIZE;
943 
944 	/* build the SSND chunk */
945 	tmp_uint = AUDIO_AIFF_SSND_ID;
946 	AUDIO_AIFF_HOST2FILE_INT(&tmp_uint, &ssnd_chunk.aiff_ssnd_ID);
947 	/* needs to be fixed when closed */
948 	tmp_uint = AUDIO_AIFF_UNKNOWN_SIZE;
949 	AUDIO_AIFF_HOST2FILE_INT(&tmp_uint, &ssnd_chunk.aiff_ssnd_size);
950 	ssnd_chunk.aiff_ssnd_offset = 0;
951 	ssnd_chunk.aiff_ssnd_block_size = 0;
952 	(void) memcpy(&buf[buf_size], &ssnd_chunk, sizeof (ssnd_chunk));
953 	buf_size += sizeof (ssnd_chunk);
954 
955 	*blen = buf_size;
956 
957 	return (AUDIO_SUCCESS);
958 
959 }	/* audio_encode_aiff() */
960 
961 /*
962  * Encode a .au file header from the supplied Audio_hdr structure and
963  * store in the supplied char* buffer. blen is the size of the buffer to
964  * store the header in. If 'infop' is not NULL, it is the address of a
965  * buffer containing 'info' data. 'ilen' specifies the size of this buffer.
966  * The entire file header will be zero-padded to a double-word boundary.
967  *
968  * NOTE: .au doesn't support unsigned 8-bit linear PCM.
969  */
970 static int
audio_encode_au(Audio_hdr * hdrp,char * infop,unsigned int ilen,unsigned char * buf,unsigned int * blen)971 audio_encode_au(Audio_hdr *hdrp, char *infop, unsigned int ilen,
972 	unsigned char *buf, unsigned int *blen)
973 					/* audio header */
974 					/* info buffer pointer */
975 					/* info buffer size */
976 					/* output buffer */
977 					/* output buffer size */
978 {
979 	au_filehdr_t	fhdr;
980 	int		encoding;
981 	int		hdrsize;
982 	int		magic;
983 	int		offset;
984 
985 	/*
986 	 * Set the size of the real header (hdr size + info size).
987 	 * If no supplied info, make sure a minimum size is accounted for.
988 	 * Also, round the whole thing up to double-word alignment.
989 	 */
990 	if ((infop == NULL) || (ilen == 0)) {
991 		infop = NULL;
992 		ilen = 4;
993 	}
994 	hdrsize = sizeof (fhdr) + ilen;
995 	offset = ROUND_DBL(hdrsize);
996 
997 	/* Check the data encoding. */
998 	switch (hdrp->encoding) {
999 	case AUDIO_ENCODING_LINEAR8:
1000 		return (AUDIO_ERR_ENCODING);	/* we don't support ulinear */
1001 	case AUDIO_ENCODING_ULAW:
1002 		if (hdrp->samples_per_unit != 1)
1003 			return (AUDIO_ERR_BADHDR);
1004 
1005 		switch (hdrp->bytes_per_unit) {
1006 		case 1:
1007 			encoding = AUDIO_AU_ENCODING_ULAW;
1008 			break;
1009 		default:
1010 			return (AUDIO_ERR_BADHDR);
1011 		}
1012 		break;
1013 	case AUDIO_ENCODING_ALAW:
1014 		if (hdrp->samples_per_unit != 1)
1015 			return (AUDIO_ERR_BADHDR);
1016 
1017 		switch (hdrp->bytes_per_unit) {
1018 		case 1:
1019 			encoding = AUDIO_AU_ENCODING_ALAW;
1020 			break;
1021 		default:
1022 			return (AUDIO_ERR_BADHDR);
1023 		}
1024 		break;
1025 	case AUDIO_ENCODING_LINEAR:
1026 		if (hdrp->samples_per_unit != 1)
1027 			return (AUDIO_ERR_BADHDR);
1028 
1029 		switch (hdrp->bytes_per_unit) {
1030 		case 1:
1031 			encoding = AUDIO_AU_ENCODING_LINEAR_8;
1032 			break;
1033 		case 2:
1034 			encoding = AUDIO_AU_ENCODING_LINEAR_16;
1035 			break;
1036 		case 3:
1037 			encoding = AUDIO_AU_ENCODING_LINEAR_24;
1038 			break;
1039 		case 4:
1040 			encoding = AUDIO_AU_ENCODING_LINEAR_32;
1041 			break;
1042 		default:
1043 			return (AUDIO_ERR_BADHDR);
1044 		}
1045 		break;
1046 	case AUDIO_ENCODING_FLOAT:
1047 		if (hdrp->samples_per_unit != 1)
1048 			return (AUDIO_ERR_BADHDR);
1049 
1050 		switch (hdrp->bytes_per_unit) {
1051 		case 4:
1052 			encoding = AUDIO_AU_ENCODING_FLOAT;
1053 			break;
1054 		case 8:
1055 			encoding = AUDIO_AU_ENCODING_DOUBLE;
1056 			break;
1057 		default:
1058 			return (AUDIO_ERR_BADHDR);
1059 		}
1060 		break;
1061 	case AUDIO_ENCODING_G721:
1062 		if (hdrp->bytes_per_unit != 1)
1063 			return (AUDIO_ERR_BADHDR);
1064 		else if (hdrp->samples_per_unit != 2)
1065 			return (AUDIO_ERR_BADHDR);
1066 		else
1067 			encoding = AUDIO_AU_ENCODING_ADPCM_G721;
1068 		break;
1069 	case AUDIO_ENCODING_G723:
1070 		if (hdrp->samples_per_unit != 8)
1071 			return (AUDIO_ERR_BADHDR);
1072 		else if (hdrp->bytes_per_unit == 3)
1073 			encoding = AUDIO_AU_ENCODING_ADPCM_G723_3;
1074 		else if (hdrp->bytes_per_unit == 5)
1075 			encoding = AUDIO_AU_ENCODING_ADPCM_G723_5;
1076 		else
1077 			return (AUDIO_ERR_BADHDR);
1078 		break;
1079 	default:
1080 		return (AUDIO_ERR_BADHDR);
1081 	}
1082 
1083 	/* copy the fhdr into the supplied buffer - make sure it'll fit */
1084 	if (*blen < offset) {
1085 		/* XXX - is this apropriate? */
1086 		return (AUDIO_EOF);
1087 	}
1088 
1089 	/* reset blen to actual size of hdr data */
1090 	*blen = (unsigned)offset;
1091 
1092 	magic = AUDIO_AU_FILE_MAGIC;	/* set the magic number */
1093 
1094 	/* Encode the audio header structure. */
1095 	AUDIO_AU_HOST2FILE(&magic, &fhdr.au_magic);
1096 	AUDIO_AU_HOST2FILE(&offset, &fhdr.au_offset);
1097 	AUDIO_AU_HOST2FILE(&hdrp->data_size, &fhdr.au_data_size);
1098 	AUDIO_AU_HOST2FILE(&encoding, &fhdr.au_encoding);
1099 	AUDIO_AU_HOST2FILE(&hdrp->sample_rate, &fhdr.au_sample_rate);
1100 	AUDIO_AU_HOST2FILE(&hdrp->channels, &fhdr.au_channels);
1101 
1102 	/* Copy to the buffer */
1103 	(void) memcpy(buf, &fhdr, sizeof (fhdr));
1104 
1105 	/* Copy the info data, if present */
1106 	if (infop != NULL) {
1107 		(void) memcpy(&buf[sizeof (fhdr)], infop, (int)ilen);
1108 		buf += ilen;
1109 	}
1110 
1111 	if (offset > hdrsize) {
1112 		(void) memset(&buf[hdrsize], '\0', (size_t)(offset - hdrsize));
1113 	}
1114 
1115 	/* buf now has the data, just return ... */
1116 
1117 	return (AUDIO_SUCCESS);
1118 
1119 }	/* audio_encode_au() */
1120 
1121 /*
1122  * Encode a .wav file header from the supplied Audio_hdr structure and
1123  * store in the supplied char* buffer. blen is the size of the buffer to
1124  * store the header in. .wav doesn't support an information string like
1125  * .au does.
1126  *
1127  * NOTE: .wav only supports a few encoding methods.
1128  */
1129 static int
audio_encode_wav(Audio_hdr * hdrp,unsigned char * buf,unsigned int * blen)1130 audio_encode_wav(Audio_hdr *hdrp, unsigned char *buf, unsigned int *blen)
1131 					/* audio header */
1132 					/* output buffer */
1133 					/* output buffer size */
1134 {
1135 	wav_filehdr_t	fhdr;
1136 	int		bytes_per_second;
1137 	int		bytes_per_sample;
1138 	int		bits_per_sample;
1139 	int		id;
1140 	int		length;
1141 	int		type;
1142 	short		encoding;
1143 
1144 	/* make sure we've got valid encoding and precision settings for .wav */
1145 	switch (hdrp->encoding) {
1146 	case AUDIO_ENCODING_LINEAR8:
1147 		if (hdrp->bytes_per_unit != 1) {
1148 			return (AUDIO_ERR_ENCODING);
1149 		}
1150 		encoding = AUDIO_WAV_FMT_ENCODING_PCM;
1151 		break;
1152 	case AUDIO_ENCODING_ULAW:
1153 		if (hdrp->bytes_per_unit != 1) {
1154 			return (AUDIO_ERR_ENCODING);
1155 		}
1156 		encoding = AUDIO_WAV_FMT_ENCODING_MULAW;
1157 		break;
1158 	case AUDIO_ENCODING_ALAW:
1159 		if (hdrp->bytes_per_unit != 1) {
1160 			return (AUDIO_ERR_ENCODING);
1161 		}
1162 		encoding = AUDIO_WAV_FMT_ENCODING_ALAW;
1163 		break;
1164 	case AUDIO_ENCODING_LINEAR:
1165 		if (hdrp->bytes_per_unit != 2) {
1166 			return (AUDIO_ERR_ENCODING);
1167 		}
1168 		encoding = AUDIO_WAV_FMT_ENCODING_PCM;
1169 		break;
1170 	default:
1171 		return (AUDIO_ERR_ENCODING);
1172 	}
1173 
1174 	/* fill in the riff chunk */
1175 	id = AUDIO_WAV_RIFF_ID;
1176 	length = AUDIO_WAV_UNKNOWN_SIZE;
1177 	AUDIO_WAV_HOST2FILE_INT(&id, &fhdr.wav_riff_ID);
1178 	AUDIO_WAV_HOST2FILE_INT(&length, &fhdr.wav_riff_size);
1179 
1180 	/* fill in the type chunk */
1181 	type = AUDIO_WAV_TYPE_ID;
1182 	AUDIO_WAV_HOST2FILE_INT(&type, &fhdr.wav_type_ID);
1183 
1184 
1185 	/* fill in the format chunk */
1186 	id = AUDIO_WAV_FORMAT_ID;
1187 	length = AUDIO_WAV_FORMAT_SIZE;
1188 	bytes_per_second = hdrp->sample_rate * hdrp->channels *
1189 	    hdrp->bytes_per_unit;
1190 	bytes_per_sample = hdrp->channels * hdrp->bytes_per_unit;
1191 	bits_per_sample = hdrp->bytes_per_unit * 8;
1192 
1193 	AUDIO_WAV_HOST2FILE_INT(&id, &fhdr.wav_fmt_ID);
1194 	AUDIO_WAV_HOST2FILE_INT(&length, &fhdr.wav_fmt_size);
1195 	AUDIO_WAV_HOST2FILE_SHORT(&encoding, &fhdr.wav_fmt_encoding);
1196 	AUDIO_WAV_HOST2FILE_SHORT(&hdrp->channels, &fhdr.wav_fmt_channels);
1197 	AUDIO_WAV_HOST2FILE_INT(&hdrp->sample_rate, &fhdr.wav_fmt_sample_rate);
1198 	AUDIO_WAV_HOST2FILE_INT(&bytes_per_second,
1199 	    &fhdr.wav_fmt_bytes_per_second);
1200 	AUDIO_WAV_HOST2FILE_SHORT(&bytes_per_sample,
1201 	    &fhdr.wav_fmt_bytes_per_sample);
1202 	AUDIO_WAV_HOST2FILE_SHORT(&bits_per_sample,
1203 	    &fhdr.wav_fmt_bits_per_sample);
1204 
1205 	/* fill in the data chunk */
1206 	id = AUDIO_WAV_DATA_ID_LC;
1207 	length = AUDIO_WAV_UNKNOWN_SIZE;
1208 	AUDIO_WAV_HOST2FILE_INT(&id, &fhdr.wav_data_ID);
1209 	AUDIO_WAV_HOST2FILE_INT(&length, &fhdr.wav_data_size);
1210 
1211 	*blen = sizeof (fhdr);
1212 
1213 	/* copy to the buffer */
1214 	(void) memcpy(buf, &fhdr, sizeof (fhdr));
1215 
1216 	return (AUDIO_SUCCESS);
1217 
1218 }	/* audio_encode_wav() */
1219 
1220 /*
1221  * Utility routine used to convert 10 byte IEEE extended float into
1222  * a regular double. Raw data arrives in an unsigned char array. Because
1223  * this is for sample rate, which is always positive, we don't worry
1224  * about the sign.
1225  */
1226 static double
convert_from_ieee_extended(unsigned char * data)1227 convert_from_ieee_extended(unsigned char *data)
1228 {
1229 	double		value = 0.0;
1230 	unsigned long	high_mantissa;
1231 	unsigned long	low_mantissa;
1232 	int		exponent;
1233 
1234 	/* first 2 bytes are the exponent */
1235 	exponent = ((data[0] & 0x7f) << 8) | data[1];
1236 
1237 	high_mantissa = ((unsigned long)data[2] << 24) |
1238 	    ((unsigned long)data[3] << 16) |
1239 	    ((unsigned long)data[4] << 8) |
1240 	    (unsigned long)data[5];
1241 	low_mantissa = ((unsigned long)data[6] << 24) |
1242 	    ((unsigned long)data[7] << 16) |
1243 	    ((unsigned long)data[8] << 8) |
1244 	    (unsigned long)data[9];
1245 
1246 	/* convert exponent and mantissas into a real double */
1247 	if (exponent == 0 && high_mantissa == 0 && low_mantissa == 0) {
1248 		/* everything is 0, so we're done */
1249 		value = 0.0;
1250 	} else {
1251 		if (exponent == 0x7fff) {	/* infinity */
1252 			value = MAXFLOAT;
1253 		} else {
1254 			/* convert exponent from being unsigned to signed */
1255 			exponent -= 0x3fff;
1256 
1257 			exponent -= 31;
1258 			value = ldexp((double)high_mantissa, exponent);
1259 
1260 			exponent -= 32;
1261 			value += ldexp((double)low_mantissa, exponent);
1262 		}
1263 	}
1264 
1265 	return (value);
1266 
1267 }
1268 
1269 /*
1270  * Utility routine to convert a double into 10 byte IEEE extended floating
1271  * point. The new number is placed into the unsigned char array. This is a
1272  * very brain dead convesion routine. It only supports integers, but then
1273  * that should be all we need for sample rate.
1274  */
1275 static void
convert_to_ieee_extended(double value,unsigned char * data)1276 convert_to_ieee_extended(double value, unsigned char *data)
1277 {
1278 	double		fmantissa;
1279 	int		exponent;
1280 	int		mantissa;
1281 
1282 	exponent = 16398;
1283 	fmantissa = value;
1284 
1285 	while (fmantissa < 44000) {
1286 		fmantissa *= 2;
1287 		exponent--;
1288 	}
1289 
1290 	mantissa = (int)fmantissa << 16;
1291 
1292 	data[0] = exponent >> 8;
1293 	data[1] = exponent;
1294 	data[2] = mantissa >> 24;
1295 	data[3] = mantissa >> 16;
1296 	data[4] = mantissa >> 8;
1297 	data[5] = mantissa;
1298 	data[6] = 0;
1299 	data[7] = 0;
1300 	data[8] = 0;
1301 	data[9] = 0;
1302 
1303 }
1304