/
flac.c
523 lines (420 loc) · 15.8 KB
/
flac.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
/*
* SDL_sound -- An abstract sound format decoding API.
* Copyright (C) 2001 Ryan C. Gordon.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
* FLAC decoder for SDL_sound.
*
* This driver handles FLAC audio, that is to say the Free Lossless Audio
* Codec. It depends on libFLAC for decoding, which can be grabbed from:
* http://flac.sourceforge.net
*
* Please see the file COPYING in the source's root directory.
*
* This file written by Torbjörn Andersson. (d91tan@Update.UU.SE)
*/
#if HAVE_CONFIG_H
# include <config.h>
#endif
#ifdef SOUND_SUPPORTS_FLAC
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "SDL_sound.h"
#define __SDL_SOUND_INTERNAL__
#include "SDL_sound_internal.h"
#include <FLAC/seekable_stream_decoder.h>
#define D_END_OF_STREAM FLAC__SEEKABLE_STREAM_DECODER_END_OF_STREAM
#define d_new() FLAC__seekable_stream_decoder_new()
#define d_init(x) FLAC__seekable_stream_decoder_init(x)
#define d_process_metadata(x) FLAC__seekable_stream_decoder_process_until_end_of_metadata(x)
#define d_process_one_frame(x) FLAC__seekable_stream_decoder_process_single(x)
#define d_get_state(x) FLAC__seekable_stream_decoder_get_state(x)
#define d_finish(x) FLAC__seekable_stream_decoder_finish(x)
#define d_delete(x) FLAC__seekable_stream_decoder_delete(x)
#define d_set_read_callback(x, y) FLAC__seekable_stream_decoder_set_read_callback(x, y)
#define d_set_write_callback(x, y) FLAC__seekable_stream_decoder_set_write_callback(x, y)
#define d_set_metadata_callback(x, y) FLAC__seekable_stream_decoder_set_metadata_callback(x, y)
#define d_set_error_callback(x, y) FLAC__seekable_stream_decoder_set_error_callback(x, y)
#define d_set_client_data(x, y) FLAC__seekable_stream_decoder_set_client_data(x, y)
typedef FLAC__SeekableStreamDecoder decoder_t;
typedef FLAC__SeekableStreamDecoderReadStatus d_read_status_t;
#define D_SEEK_STATUS_OK FLAC__SEEKABLE_STREAM_DECODER_SEEK_STATUS_OK
#define D_SEEK_STATUS_ERROR FLAC__SEEKABLE_STREAM_DECODER_SEEK_STATUS_ERROR
#define D_TELL_STATUS_OK FLAC__SEEKABLE_STREAM_DECODER_TELL_STATUS_OK
#define D_TELL_STATUS_ERROR FLAC__SEEKABLE_STREAM_DECODER_TELL_STATUS_ERROR
#define D_LENGTH_STATUS_OK FLAC__SEEKABLE_STREAM_DECODER_LENGTH_STATUS_OK
#define D_LENGTH_STATUS_ERROR FLAC__SEEKABLE_STREAM_DECODER_LENGTH_STATUS_ERROR
#define d_set_seek_callback(x, y) FLAC__seekable_stream_decoder_set_seek_callback(x, y)
#define d_set_tell_callback(x, y) FLAC__seekable_stream_decoder_set_tell_callback(x, y)
#define d_set_length_callback(x, y) FLAC__seekable_stream_decoder_set_length_callback(x, y)
#define d_set_eof_callback(x, y) FLAC__seekable_stream_decoder_set_eof_callback(x, y)
#define d_seek_absolute(x, y) FLAC__seekable_stream_decoder_seek_absolute(x, y)
typedef FLAC__SeekableStreamDecoderSeekStatus d_seek_status_t;
typedef FLAC__SeekableStreamDecoderTellStatus d_tell_status_t;
typedef FLAC__SeekableStreamDecoderLengthStatus d_length_status_t;
#define D_WRITE_CONTINUE FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE
#define D_READ_END_OF_STREAM FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM
#define D_READ_ABORT FLAC__STREAM_DECODER_READ_STATUS_ABORT
#define D_READ_CONTINUE FLAC__STREAM_DECODER_READ_STATUS_CONTINUE
#define d_error_status_string FLAC__StreamDecoderErrorStatusString
typedef FLAC__StreamDecoderErrorStatus d_error_status_t;
typedef FLAC__StreamMetadata d_metadata_t;
typedef FLAC__StreamDecoderWriteStatus d_write_status_t;
static int FLAC_init(void);
static void FLAC_quit(void);
static int FLAC_open(Sound_Sample *sample, const char *ext);
static void FLAC_close(Sound_Sample *sample);
static Uint32 FLAC_read(Sound_Sample *sample);
static int FLAC_rewind(Sound_Sample *sample);
static int FLAC_seek(Sound_Sample *sample, Uint32 ms);
static const char *extensions_flac[] = { "FLAC", "FLA", NULL };
const Sound_DecoderFunctions __Sound_DecoderFunctions_FLAC =
{
{
extensions_flac,
"Free Lossless Audio Codec",
"Torbjörn Andersson <d91tan@Update.UU.SE>",
"http://flac.sourceforge.net/"
},
FLAC_init, /* init() method */
FLAC_quit, /* quit() method */
FLAC_open, /* open() method */
FLAC_close, /* close() method */
FLAC_read, /* read() method */
FLAC_rewind, /* rewind() method */
FLAC_seek /* seek() method */
};
/* This is what we store in our internal->decoder_private field. */
typedef struct
{
decoder_t *decoder;
SDL_RWops *rw;
Sound_Sample *sample;
Uint32 frame_size;
Uint8 is_flac;
Uint32 stream_length;
} flac_t;
static void free_flac(flac_t *f)
{
d_finish(f->decoder);
d_delete(f->decoder);
free(f);
} /* free_flac */
static d_read_status_t read_callback(
const decoder_t *decoder, FLAC__byte buffer[],
unsigned int *bytes, void *client_data)
{
flac_t *f = (flac_t *) client_data;
Uint32 retval;
retval = SDL_RWread(f->rw, (Uint8 *) buffer, 1, *bytes);
if (retval == 0)
{
*bytes = 0;
f->sample->flags |= SOUND_SAMPLEFLAG_EOF;
return(D_READ_END_OF_STREAM);
} /* if */
if (retval == -1)
{
*bytes = 0;
f->sample->flags |= SOUND_SAMPLEFLAG_ERROR;
return(D_READ_ABORT);
} /* if */
if (retval < *bytes)
{
*bytes = retval;
f->sample->flags |= SOUND_SAMPLEFLAG_EAGAIN;
} /* if */
return(D_READ_CONTINUE);
} /* read_callback */
static d_write_status_t write_callback(
const decoder_t *decoder, const FLAC__Frame *frame,
const FLAC__int32 * const buffer[],
void *client_data)
{
flac_t *f = (flac_t *) client_data;
Uint32 i, j;
Uint32 sample;
Uint8 *dst;
f->frame_size = frame->header.channels * frame->header.blocksize
* frame->header.bits_per_sample / 8;
if (f->frame_size > f->sample->buffer_size)
Sound_SetBufferSize(f->sample, f->frame_size);
dst = f->sample->buffer;
/* If the sample is neither exactly 8-bit nor 16-bit, it will have to
* be converted. Unfortunately the buffer is read-only, so we either
* have to check for each sample, or make a copy of the buffer. I'm
* not sure which way is best, so I've arbitrarily picked the former.
*/
if (f->sample->actual.format == AUDIO_S8)
{
for (i = 0; i < frame->header.blocksize; i++)
for (j = 0; j < frame->header.channels; j++)
{
sample = buffer[j][i];
if (frame->header.bits_per_sample < 8)
sample <<= (8 - frame->header.bits_per_sample);
*dst++ = sample & 0x00ff;
} /* for */
} /* if */
else
{
for (i = 0; i < frame->header.blocksize; i++)
for (j = 0; j < frame->header.channels; j++)
{
sample = buffer[j][i];
if (frame->header.bits_per_sample < 16)
sample <<= (16 - frame->header.bits_per_sample);
else if (frame->header.bits_per_sample > 16)
sample >>= (frame->header.bits_per_sample - 16);
*dst++ = (sample & 0xff00) >> 8;
*dst++ = sample & 0x00ff;
} /* for */
} /* else */
return(D_WRITE_CONTINUE);
} /* write_callback */
static void metadata_callback(
const decoder_t *decoder,
const d_metadata_t *metadata,
void *client_data)
{
flac_t *f = (flac_t *) client_data;
SNDDBG(("FLAC: Metadata callback.\n"));
/* There are several kinds of metadata, but STREAMINFO is the only
* one that always has to be there.
*/
if (metadata->type == FLAC__METADATA_TYPE_STREAMINFO)
{
SNDDBG(("FLAC: Metadata is streaminfo.\n"));
f->is_flac = 1;
f->sample->actual.channels = metadata->data.stream_info.channels;
f->sample->actual.rate = metadata->data.stream_info.sample_rate;
if (metadata->data.stream_info.sample_rate == 0 ||
metadata->data.stream_info.total_samples == 0)
f->sample->total_time = -1;
else {
f->sample->total_time = (metadata->data.stream_info.total_samples)
/ metadata->data.stream_info.sample_rate * 1000;
f->sample->total_time += (metadata->data.stream_info.total_samples
% metadata->data.stream_info.sample_rate) * 1000
/ metadata->data.stream_info.sample_rate;
}
if (metadata->data.stream_info.bits_per_sample > 8)
f->sample->actual.format = AUDIO_S16MSB;
else
f->sample->actual.format = AUDIO_S8;
} /* if */
} /* metadata_callback */
static void error_callback(
const decoder_t *decoder,
d_error_status_t status,
void *client_data)
{
flac_t *f = (flac_t *) client_data;
__Sound_SetError(d_error_status_string[status]);
f->sample->flags |= SOUND_SAMPLEFLAG_ERROR;
} /* error_callback */
static d_seek_status_t seek_callback(
const decoder_t *decoder,
FLAC__uint64 absolute_byte_offset,
void *client_data)
{
flac_t *f = (flac_t *) client_data;
if (SDL_RWseek(f->rw, absolute_byte_offset, SEEK_SET) >= 0)
{
return(D_SEEK_STATUS_OK);
} /* if */
return(D_SEEK_STATUS_ERROR);
} /* seek_callback*/
static d_tell_status_t tell_callback(
const decoder_t *decoder,
FLAC__uint64 *absolute_byte_offset,
void *client_data)
{
flac_t *f = (flac_t *) client_data;
int pos;
pos = SDL_RWtell(f->rw);
if (pos < 0)
{
return(D_TELL_STATUS_ERROR);
} /* if */
*absolute_byte_offset = pos;
return(D_TELL_STATUS_OK);
} /* tell_callback */
static d_length_status_t length_callback(
const decoder_t *decoder,
FLAC__uint64 *stream_length,
void *client_data)
{
flac_t *f = (flac_t *) client_data;
if (f->sample->flags & SOUND_SAMPLEFLAG_CANSEEK)
{
*stream_length = f->stream_length;
return(D_LENGTH_STATUS_OK);
} /* if */
return(D_LENGTH_STATUS_ERROR);
} /* length_callback */
static FLAC__bool eof_callback(
const decoder_t *decoder,
void *client_data)
{
flac_t *f = (flac_t *) client_data;
int pos;
/* Maybe we could check for SOUND_SAMPLEFLAG_EOF here instead? */
pos = SDL_RWtell(f->rw);
if (pos >= 0 && pos >= f->stream_length)
{
return(true);
} /* if */
return(false);
} /* eof_callback */
static int FLAC_init(void)
{
return(1); /* always succeeds. */
} /* FLAC_init */
static void FLAC_quit(void)
{
/* it's a no-op. */
} /* FLAC_quit */
#define FLAC_MAGIC 0x43614C66 /* "fLaC" in ASCII. */
static int FLAC_open(Sound_Sample *sample, const char *ext)
{
Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;
SDL_RWops *rw = internal->rw;
decoder_t *decoder;
flac_t *f;
int i;
int has_extension = 0;
Uint32 pos;
/*
* If the extension is "flac", we'll believe that this is really meant
* to be a FLAC stream, and will try to grok it from existing metadata.
* metadata searching can be a very expensive operation, however, so
* unless the user swears that it is a FLAC stream through the extension,
* we decide what to do based on the existance of a 32-bit magic number.
*/
for (i = 0; extensions_flac[i] != NULL; i++)
{
if (__Sound_strcasecmp(ext, extensions_flac[i]) == 0)
{
has_extension = 1;
break;
} /* if */
} /* for */
if (!has_extension)
{
int rc;
Uint32 flac_magic = SDL_ReadLE32(rw);
BAIL_IF_MACRO(flac_magic != FLAC_MAGIC, "FLAC: Not a FLAC stream.", 0);
/* move back over magic number for metadata scan... */
rc = SDL_RWseek(internal->rw, -sizeof (flac_magic), SEEK_CUR);
BAIL_IF_MACRO(rc < 0, ERR_IO_ERROR, 0);
} /* if */
f = (flac_t *) malloc(sizeof (flac_t));
BAIL_IF_MACRO(f == NULL, ERR_OUT_OF_MEMORY, 0);
decoder = d_new();
if (decoder == NULL)
{
free(f);
BAIL_MACRO(ERR_OUT_OF_MEMORY, 0);
} /* if */
d_set_read_callback(decoder, read_callback);
d_set_write_callback(decoder, write_callback);
d_set_metadata_callback(decoder, metadata_callback);
d_set_error_callback(decoder, error_callback);
d_set_seek_callback(decoder, seek_callback);
d_set_tell_callback(decoder, tell_callback);
d_set_length_callback(decoder, length_callback);
d_set_eof_callback(decoder, eof_callback);
d_set_client_data(decoder, f);
f->rw = internal->rw;
f->sample = sample;
f->decoder = decoder;
f->sample->actual.format = 0;
f->is_flac = 0 /* !!! FIXME: should be "has_extension", not "0". */;
internal->decoder_private = f;
d_init(decoder);
sample->flags = SOUND_SAMPLEFLAG_NONE;
pos = SDL_RWtell(f->rw);
if (SDL_RWseek(f->rw, 0, SEEK_END) > 0)
{
f->stream_length = SDL_RWtell(f->rw);
if (SDL_RWseek(f->rw, pos, SEEK_SET) == -1)
{
free_flac(f);
BAIL_MACRO(ERR_IO_ERROR, 0);
} /* if */
sample->flags = SOUND_SAMPLEFLAG_CANSEEK;
} /* if */
/*
* If we are not sure this is a FLAC stream, check for the STREAMINFO
* metadata block. If not, we'd have to peek at the first audio frame
* and get the sound format from there, but that is not yet
* implemented.
*/
if (!f->is_flac)
{
d_process_metadata(decoder);
/* Still not FLAC? Give up. */
if (!f->is_flac)
{
free_flac(f);
BAIL_MACRO("FLAC: No metadata found. Not a FLAC stream?", 0);
} /* if */
} /* if */
SNDDBG(("FLAC: Accepting data stream.\n"));
return(1);
} /* FLAC_open */
static void FLAC_close(Sound_Sample *sample)
{
Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;
flac_t *f = (flac_t *) internal->decoder_private;
free_flac(f);
} /* FLAC_close */
static Uint32 FLAC_read(Sound_Sample *sample)
{
Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;
flac_t *f = (flac_t *) internal->decoder_private;
Uint32 len;
if (!d_process_one_frame(f->decoder))
{
sample->flags |= SOUND_SAMPLEFLAG_ERROR;
BAIL_MACRO("FLAC: Couldn't decode frame.", 0);
} /* if */
if (d_get_state(f->decoder) == D_END_OF_STREAM)
{
sample->flags |= SOUND_SAMPLEFLAG_EOF;
return(0);
} /* if */
/* An error may have been signalled through the error callback. */
if (sample->flags & SOUND_SAMPLEFLAG_ERROR)
return(0);
return(f->frame_size);
} /* FLAC_read */
static int FLAC_rewind(Sound_Sample *sample)
{
return FLAC_seek(sample, 0);
} /* FLAC_rewind */
static int FLAC_seek(Sound_Sample *sample, Uint32 ms)
{
Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;
flac_t *f = (flac_t *) internal->decoder_private;
d_seek_absolute(f->decoder, (ms * sample->actual.rate) / 1000);
return(1);
} /* FLAC_seek */
#endif /* SOUND_SUPPORTS_FLAC */
/* end of flac.c ... */