src/libOggFLAC/stream_decoder.c

   1 /* libOggFLAC - Free Lossless Audio Codec + Ogg library
   2  * Copyright (C) 2002  Josh Coalson
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Library General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Library General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Library General Public
  15  * License along with this library; if not, write to the
  16  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17  * Boston, MA  02111-1307, USA.
  18  */
  19
  20 #include <stdlib.h> /* for calloc() */
  21 #include <string.h> /* for memset() */
  22 #include <ogg/ogg.h>
  23 #include "FLAC/assert.h"
  24 #include "protected/stream_decoder.h"
  25
  26 #ifdef min
  27 #undef min
  28 #endif
  29 #define min(x,y) ((x)<(y)?(x):(y))
  30
  31 /***********************************************************************
  32  *
  33  * Private class method prototypes
  34  *
  35  ***********************************************************************/
  36
  37 static void set_defaults_(OggFLAC__StreamDecoder *decoder);
  38 static FLAC__StreamDecoderReadStatus read_callback_(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], unsigned *bytes, void *client_data);
  39 static FLAC__StreamDecoderWriteStatus write_callback_(const FLAC__StreamDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[], void *client_data);
  40 static void metadata_callback_(const FLAC__StreamDecoder *decoder, const FLAC__StreamMetadata *metadata, void *client_data);
  41 static void error_callback_(const FLAC__StreamDecoder *decoder, FLAC__StreamDecoderErrorStatus status, void *client_data);
  42
  43
  44 /***********************************************************************
  45  *
  46  * Private class data
  47  *
  48  ***********************************************************************/
  49
  50 typedef struct OggFLAC__StreamDecoderPrivate {
  51         OggFLAC__StreamDecoderReadCallback read_callback;
  52         OggFLAC__StreamDecoderWriteCallback write_callback;
  53         OggFLAC__StreamDecoderMetadataCallback metadata_callback;
  54         OggFLAC__StreamDecoderErrorCallback error_callback;
  55         void *client_data;
  56         FLAC__StreamDecoder *FLAC_stream_decoder;
  57         struct {
  58                 ogg_stream_state stream_state;
  59                 ogg_sync_state sync_state;
  60                 FLAC__bool need_serial_number;
  61         } ogg;
  62 } OggFLAC__StreamDecoderPrivate;
  63
  64 /***********************************************************************
  65  *
  66  * Public static class data
  67  *
  68  ***********************************************************************/
  69
  70 const OggFLAC_API char * const OggFLAC__StreamDecoderStateString[] = {
  71         "OggFLAC__STREAM_DECODER_OK",
  72         "OggFLAC__STREAM_DECODER_OGG_ERROR",
  73         "OggFLAC__STREAM_DECODER_READ_ERROR",
  74         "OggFLAC__STREAM_DECODER_FLAC_STREAM_DECODER_ERROR",
  75         "OggFLAC__STREAM_DECODER_INVALID_CALLBACK",
  76         "OggFLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR",
  77         "OggFLAC__STREAM_DECODER_ALREADY_INITIALIZED",
  78         "OggFLAC__STREAM_DECODER_UNINITIALIZED"
  79 };
  80
  81
  82 /***********************************************************************
  83  *
  84  * Class constructor/destructor
  85  *
  86  ***********************************************************************/
  87 OggFLAC_API OggFLAC__StreamDecoder *OggFLAC__stream_decoder_new()
  88 {
  89         OggFLAC__StreamDecoder *decoder;
  90
  91         decoder = (OggFLAC__StreamDecoder*)calloc(1, sizeof(OggFLAC__StreamDecoder));
  92         if(decoder == 0) {
  93                 return 0;
  94         }
  95
  96         decoder->protected_ = (OggFLAC__StreamDecoderProtected*)calloc(1, sizeof(OggFLAC__StreamDecoderProtected));
  97         if(decoder->protected_ == 0) {
  98                 free(decoder);
  99                 return 0;
 100         }
 101
 102         decoder->private_ = (OggFLAC__StreamDecoderPrivate*)calloc(1, sizeof(OggFLAC__StreamDecoderPrivate));
 103         if(decoder->private_ == 0) {
 104                 free(decoder->protected_);
 105                 free(decoder);
 106                 return 0;
 107         }
 108
 109         decoder->private_->FLAC_stream_decoder = FLAC__stream_decoder_new();
 110         if(0 == decoder->private_->FLAC_stream_decoder) {
 111                 free(decoder->private_);
 112                 free(decoder->protected_);
 113                 free(decoder);
 114                 return 0;
 115         }
 116
 117         set_defaults_(decoder);
 118
 119         decoder->protected_->state = OggFLAC__STREAM_DECODER_UNINITIALIZED;
 120
 121         return decoder;
 122 }
 123
 124 OggFLAC_API void OggFLAC__stream_decoder_delete(OggFLAC__StreamDecoder *decoder)
 125 {
 126         FLAC__ASSERT(0 != decoder);
 127         FLAC__ASSERT(0 != decoder->protected_);
 128         FLAC__ASSERT(0 != decoder->private_);
 129         FLAC__ASSERT(0 != decoder->private_->FLAC_stream_decoder);
 130
 131         OggFLAC__stream_decoder_finish(decoder);
 132
 133         FLAC__stream_decoder_delete(decoder->private_->FLAC_stream_decoder);
 134
 135         free(decoder->private_);
 136         free(decoder->protected_);
 137         free(decoder);
 138 }
 139
 140 /***********************************************************************
 141  *
 142  * Public class methods
 143  *
 144  ***********************************************************************/
 145
 146 OggFLAC_API OggFLAC__StreamDecoderState OggFLAC__stream_decoder_init(OggFLAC__StreamDecoder *decoder)
 147 {
 148         FLAC__ASSERT(0 != decoder);
 149
 150         if(decoder->protected_->state != OggFLAC__STREAM_DECODER_UNINITIALIZED)
 151                 return decoder->protected_->state = OggFLAC__STREAM_DECODER_ALREADY_INITIALIZED;
 152
 153         if(0 == decoder->private_->read_callback || 0 == decoder->private_->write_callback || 0 == decoder->private_->metadata_callback || 0 == decoder->private_->error_callback)
 154                 return decoder->protected_->state = OggFLAC__STREAM_DECODER_INVALID_CALLBACK;
 155
 156         decoder->private_->ogg.need_serial_number = decoder->protected_->use_first_serial_number;
 157         /* we will determine the serial number later if necessary */
 158         if(ogg_stream_init(&decoder->private_->ogg.stream_state, decoder->protected_->serial_number) != 0)
 159                 return decoder->protected_->state = OggFLAC__STREAM_DECODER_OGG_ERROR;
 160
 161         if(ogg_sync_init(&decoder->private_->ogg.sync_state) != 0)
 162                 return decoder->protected_->state = OggFLAC__STREAM_DECODER_OGG_ERROR;
 163
 164         FLAC__stream_decoder_set_read_callback(decoder->private_->FLAC_stream_decoder, read_callback_);
 165         FLAC__stream_decoder_set_write_callback(decoder->private_->FLAC_stream_decoder, write_callback_);
 166         FLAC__stream_decoder_set_metadata_callback(decoder->private_->FLAC_stream_decoder, metadata_callback_);
 167         FLAC__stream_decoder_set_error_callback(decoder->private_->FLAC_stream_decoder, error_callback_);
 168         FLAC__stream_decoder_set_client_data(decoder->private_->FLAC_stream_decoder, decoder);
 169
 170         if(FLAC__stream_decoder_init(decoder->private_->FLAC_stream_decoder) != FLAC__STREAM_DECODER_SEARCH_FOR_METADATA)
 171                 return decoder->protected_->state = OggFLAC__STREAM_DECODER_FLAC_STREAM_DECODER_ERROR;
 172
 173         return decoder->protected_->state = OggFLAC__STREAM_DECODER_OK;
 174 }
 175
 176 OggFLAC_API void OggFLAC__stream_decoder_finish(OggFLAC__StreamDecoder *decoder)
 177 {
 178         FLAC__ASSERT(0 != decoder);
 179         FLAC__ASSERT(0 != decoder->private_);
 180         FLAC__ASSERT(0 != decoder->protected_);
 181
 182         if(decoder->protected_->state == OggFLAC__STREAM_DECODER_UNINITIALIZED)
 183                 return;
 184
 185         FLAC__ASSERT(0 != decoder->private_->FLAC_stream_decoder);
 186
 187         FLAC__stream_decoder_finish(decoder->private_->FLAC_stream_decoder);
 188
 189         (void)ogg_sync_clear(&decoder->private_->ogg.sync_state);
 190         (void)ogg_stream_clear(&decoder->private_->ogg.stream_state);
 191
 192         set_defaults_(decoder);
 193
 194         decoder->protected_->state = OggFLAC__STREAM_DECODER_UNINITIALIZED;
 195 }
 196
 197 OggFLAC_API FLAC__bool OggFLAC__stream_decoder_set_read_callback(OggFLAC__StreamDecoder *decoder, OggFLAC__StreamDecoderReadCallback value)
 198 {
 199         FLAC__ASSERT(0 != decoder);
 200         FLAC__ASSERT(0 != decoder->private_);
 201         FLAC__ASSERT(0 != decoder->protected_);
 202         if(decoder->protected_->state != OggFLAC__STREAM_DECODER_UNINITIALIZED)
 203                 return false;
 204         decoder->private_->read_callback = value;
 205         return true;
 206 }
 207
 208 OggFLAC_API FLAC__bool OggFLAC__stream_decoder_set_write_callback(OggFLAC__StreamDecoder *decoder, OggFLAC__StreamDecoderWriteCallback value)
 209 {
 210         FLAC__ASSERT(0 != decoder);
 211         FLAC__ASSERT(0 != decoder->private_);
 212         FLAC__ASSERT(0 != decoder->protected_);
 213         if(decoder->protected_->state != OggFLAC__STREAM_DECODER_UNINITIALIZED)
 214                 return false;
 215         decoder->private_->write_callback = value;
 216         return true;
 217 }
 218
 219 OggFLAC_API FLAC__bool OggFLAC__stream_decoder_set_metadata_callback(OggFLAC__StreamDecoder *decoder, OggFLAC__StreamDecoderMetadataCallback value)
 220 {
 221         FLAC__ASSERT(0 != decoder);
 222         FLAC__ASSERT(0 != decoder->private_);
 223         FLAC__ASSERT(0 != decoder->protected_);
 224         if(decoder->protected_->state != OggFLAC__STREAM_DECODER_UNINITIALIZED)
 225                 return false;
 226         decoder->private_->metadata_callback = value;
 227         return true;
 228 }
 229
 230 OggFLAC_API FLAC__bool OggFLAC__stream_decoder_set_error_callback(OggFLAC__StreamDecoder *decoder, OggFLAC__StreamDecoderErrorCallback value)
 231 {
 232         FLAC__ASSERT(0 != decoder);
 233         FLAC__ASSERT(0 != decoder->private_);
 234         FLAC__ASSERT(0 != decoder->protected_);
 235         if(decoder->protected_->state != OggFLAC__STREAM_DECODER_UNINITIALIZED)
 236                 return false;
 237         decoder->private_->error_callback = value;
 238         return true;
 239 }
 240
 241 OggFLAC_API FLAC__bool OggFLAC__stream_decoder_set_client_data(OggFLAC__StreamDecoder *decoder, void *value)
 242 {
 243         FLAC__ASSERT(0 != decoder);
 244         FLAC__ASSERT(0 != decoder->private_);
 245         FLAC__ASSERT(0 != decoder->protected_);
 246         if(decoder->protected_->state != OggFLAC__STREAM_DECODER_UNINITIALIZED)
 247                 return false;
 248         decoder->private_->client_data = value;
 249         return true;
 250 }
 251
 252 OggFLAC_API FLAC__bool OggFLAC__stream_decoder_set_serial_number(OggFLAC__StreamDecoder *decoder, long value)
 253 {
 254         FLAC__ASSERT(0 != decoder);
 255         FLAC__ASSERT(0 != decoder->private_);
 256         FLAC__ASSERT(0 != decoder->protected_);
 257         if(decoder->protected_->state != OggFLAC__STREAM_DECODER_UNINITIALIZED)
 258                 return false;
 259         decoder->protected_->use_first_serial_number = false;
 260         decoder->protected_->serial_number = value;
 261         return true;
 262 }
 263
 264 OggFLAC_API FLAC__bool OggFLAC__stream_decoder_set_metadata_respond(OggFLAC__StreamDecoder *decoder, FLAC__MetadataType type)
 265 {
 266         FLAC__ASSERT(0 != decoder);
 267         FLAC__ASSERT(0 != decoder->private_);
 268         FLAC__ASSERT(0 != decoder->protected_);
 269         if(decoder->protected_->state != OggFLAC__STREAM_DECODER_UNINITIALIZED)
 270                 return false;
 271         return FLAC__stream_decoder_set_metadata_respond(decoder->private_->FLAC_stream_decoder, type);
 272 }
 273
 274 OggFLAC_API FLAC__bool OggFLAC__stream_decoder_set_metadata_respond_application(OggFLAC__StreamDecoder *decoder, const FLAC__byte id[4])
 275 {
 276         FLAC__ASSERT(0 != decoder);
 277         FLAC__ASSERT(0 != decoder->private_);
 278         FLAC__ASSERT(0 != decoder->protected_);
 279         if(decoder->protected_->state != OggFLAC__STREAM_DECODER_UNINITIALIZED)
 280                 return false;
 281         return FLAC__stream_decoder_set_metadata_respond_application(decoder->private_->FLAC_stream_decoder, id);
 282 }
 283
 284 OggFLAC_API FLAC__bool OggFLAC__stream_decoder_set_metadata_respond_all(OggFLAC__StreamDecoder *decoder)
 285 {
 286         FLAC__ASSERT(0 != decoder);
 287         FLAC__ASSERT(0 != decoder->private_);
 288         FLAC__ASSERT(0 != decoder->protected_);
 289         if(decoder->protected_->state != OggFLAC__STREAM_DECODER_UNINITIALIZED)
 290                 return false;
 291         return FLAC__stream_decoder_set_metadata_respond_all(decoder->private_->FLAC_stream_decoder);
 292 }
 293
 294 OggFLAC_API FLAC__bool OggFLAC__stream_decoder_set_metadata_ignore(OggFLAC__StreamDecoder *decoder, FLAC__MetadataType type)
 295 {
 296         FLAC__ASSERT(0 != decoder);
 297         FLAC__ASSERT(0 != decoder->private_);
 298         FLAC__ASSERT(0 != decoder->protected_);
 299         if(decoder->protected_->state != OggFLAC__STREAM_DECODER_UNINITIALIZED)
 300                 return false;
 301         return FLAC__stream_decoder_set_metadata_ignore(decoder->private_->FLAC_stream_decoder, type);
 302 }
 303
 304 OggFLAC_API FLAC__bool OggFLAC__stream_decoder_set_metadata_ignore_application(OggFLAC__StreamDecoder *decoder, const FLAC__byte id[4])
 305 {
 306         FLAC__ASSERT(0 != decoder);
 307         FLAC__ASSERT(0 != decoder->private_);
 308         FLAC__ASSERT(0 != decoder->protected_);
 309         if(decoder->protected_->state != OggFLAC__STREAM_DECODER_UNINITIALIZED)
 310                 return false;
 311         return FLAC__stream_decoder_set_metadata_ignore_application(decoder->private_->FLAC_stream_decoder, id);
 312 }
 313
 314 OggFLAC_API FLAC__bool OggFLAC__stream_decoder_set_metadata_ignore_all(OggFLAC__StreamDecoder *decoder)
 315 {
 316         FLAC__ASSERT(0 != decoder);
 317         FLAC__ASSERT(0 != decoder->private_);
 318         FLAC__ASSERT(0 != decoder->protected_);
 319         if(decoder->protected_->state != OggFLAC__STREAM_DECODER_UNINITIALIZED)
 320                 return false;
 321         return FLAC__stream_decoder_set_metadata_ignore_all(decoder->private_->FLAC_stream_decoder);
 322 }
 323
 324 OggFLAC_API OggFLAC__StreamDecoderState OggFLAC__stream_decoder_get_state(const OggFLAC__StreamDecoder *decoder)
 325 {
 326         FLAC__ASSERT(0 != decoder);
 327         FLAC__ASSERT(0 != decoder->protected_);
 328         return decoder->protected_->state;
 329 }
 330
 331 OggFLAC_API FLAC__StreamDecoderState OggFLAC__stream_decoder_get_FLAC_stream_decoder_state(const OggFLAC__StreamDecoder *decoder)
 332 {
 333         FLAC__ASSERT(0 != decoder);
 334         FLAC__ASSERT(0 != decoder->private_);
 335         return FLAC__stream_decoder_get_state(decoder->private_->FLAC_stream_decoder);
 336 }
 337
 338 OggFLAC_API unsigned OggFLAC__stream_decoder_get_channels(const OggFLAC__StreamDecoder *decoder)
 339 {
 340         FLAC__ASSERT(0 != decoder);
 341         FLAC__ASSERT(0 != decoder->private_);
 342         return FLAC__stream_decoder_get_channels(decoder->private_->FLAC_stream_decoder);
 343 }
 344
 345 OggFLAC_API FLAC__ChannelAssignment OggFLAC__stream_decoder_get_channel_assignment(const OggFLAC__StreamDecoder *decoder)
 346 {
 347         FLAC__ASSERT(0 != decoder);
 348         FLAC__ASSERT(0 != decoder->private_);
 349         return FLAC__stream_decoder_get_channel_assignment(decoder->private_->FLAC_stream_decoder);
 350 }
 351
 352 OggFLAC_API unsigned OggFLAC__stream_decoder_get_bits_per_sample(const OggFLAC__StreamDecoder *decoder)
 353 {
 354         FLAC__ASSERT(0 != decoder);
 355         FLAC__ASSERT(0 != decoder->private_);
 356         return FLAC__stream_decoder_get_bits_per_sample(decoder->private_->FLAC_stream_decoder);
 357 }
 358
 359 OggFLAC_API unsigned OggFLAC__stream_decoder_get_sample_rate(const OggFLAC__StreamDecoder *decoder)
 360 {
 361         FLAC__ASSERT(0 != decoder);
 362         FLAC__ASSERT(0 != decoder->private_);
 363         return FLAC__stream_decoder_get_sample_rate(decoder->private_->FLAC_stream_decoder);
 364 }
 365
 366 OggFLAC_API unsigned OggFLAC__stream_decoder_get_blocksize(const OggFLAC__StreamDecoder *decoder)
 367 {
 368         FLAC__ASSERT(0 != decoder);
 369         FLAC__ASSERT(0 != decoder->private_);
 370         return FLAC__stream_decoder_get_blocksize(decoder->private_->FLAC_stream_decoder);
 371 }
 372
 373 OggFLAC_API FLAC__bool OggFLAC__stream_decoder_flush(OggFLAC__StreamDecoder *decoder)
 374 {
 375         FLAC__ASSERT(0 != decoder);
 376         FLAC__ASSERT(0 != decoder->private_);
 377         FLAC__ASSERT(0 != decoder->protected_);
 378
 379         (void)ogg_sync_clear(&decoder->private_->ogg.sync_state);
 380
 381         if(!FLAC__stream_decoder_flush(decoder->private_->FLAC_stream_decoder)) {
 382                 decoder->protected_->state = OggFLAC__STREAM_DECODER_FLAC_STREAM_DECODER_ERROR;
 383                 return false;
 384         }
 385
 386         decoder->protected_->state = OggFLAC__STREAM_DECODER_OK;
 387
 388         return true;
 389 }
 390
 391 OggFLAC_API FLAC__bool OggFLAC__stream_decoder_reset(OggFLAC__StreamDecoder *decoder)
 392 {
 393         FLAC__ASSERT(0 != decoder);
 394         FLAC__ASSERT(0 != decoder->private_);
 395         FLAC__ASSERT(0 != decoder->protected_);
 396
 397         if(!OggFLAC__stream_decoder_flush(decoder)) {
 398                 decoder->protected_->state = OggFLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
 399                 return false;
 400         }
 401
 402         if(!FLAC__stream_decoder_reset(decoder->private_->FLAC_stream_decoder)) {
 403                 decoder->protected_->state = OggFLAC__STREAM_DECODER_FLAC_STREAM_DECODER_ERROR;
 404                 return false;
 405         }
 406
 407         decoder->protected_->state = OggFLAC__STREAM_DECODER_OK;
 408
 409         return true;
 410 }
 411
 412 OggFLAC_API FLAC__bool OggFLAC__stream_decoder_process_single(OggFLAC__StreamDecoder *decoder)
 413 {
 414         FLAC__ASSERT(0 != decoder);
 415         FLAC__ASSERT(0 != decoder->private_);
 416         return FLAC__stream_decoder_process_single(decoder->private_->FLAC_stream_decoder);
 417 }
 418
 419 OggFLAC_API FLAC__bool OggFLAC__stream_decoder_process_until_end_of_metadata(OggFLAC__StreamDecoder *decoder)
 420 {
 421         FLAC__ASSERT(0 != decoder);
 422         FLAC__ASSERT(0 != decoder->private_);
 423         return FLAC__stream_decoder_process_until_end_of_metadata(decoder->private_->FLAC_stream_decoder);
 424 }
 425
 426 OggFLAC_API FLAC__bool OggFLAC__stream_decoder_process_until_end_of_stream(OggFLAC__StreamDecoder *decoder)
 427 {
 428         FLAC__ASSERT(0 != decoder);
 429         FLAC__ASSERT(0 != decoder->private_);
 430         return FLAC__stream_decoder_process_until_end_of_stream(decoder->private_->FLAC_stream_decoder);
 431 }
 432
 433
 434 /***********************************************************************
 435  *
 436  * Private class methods
 437  *
 438  ***********************************************************************/
 439
 440 void set_defaults_(OggFLAC__StreamDecoder *decoder)
 441 {
 442         decoder->private_->read_callback = 0;
 443         decoder->private_->write_callback = 0;
 444         decoder->private_->metadata_callback = 0;
 445         decoder->private_->error_callback = 0;
 446         decoder->private_->client_data = 0;
 447         decoder->protected_->use_first_serial_number = true;
 448 }
 449
 450 FLAC__StreamDecoderReadStatus read_callback_(const FLAC__StreamDecoder *unused, FLAC__byte buffer[], unsigned *bytes, void *client_data)
 451 {
 452         static const unsigned OGG_BYTES_CHUNK = 8192;
 453         OggFLAC__StreamDecoder *decoder = (OggFLAC__StreamDecoder*)client_data;
 454         unsigned ogg_bytes_to_read, ogg_bytes_read;
 455         ogg_page page;
 456         char *oggbuf;
 457
 458         (void)unused;
 459
 460         /*
 461          * We have to be careful not to read in more than the
 462          * FLAC__StreamDecoder says it has room for.  We know
 463          * that the size of the decoded data must be no more
 464          * than the encoded data we will read.
 465          */
 466         ogg_bytes_to_read = min(*bytes, OGG_BYTES_CHUNK);
 467         oggbuf = ogg_sync_buffer(&decoder->private_->ogg.sync_state, ogg_bytes_to_read);
 468
 469         if(decoder->private_->read_callback(decoder, oggbuf, &ogg_bytes_to_read, decoder->private_->client_data) != FLAC__STREAM_DECODER_READ_STATUS_CONTINUE) {
 470                 decoder->protected_->state = OggFLAC__STREAM_DECODER_READ_ERROR;
 471                 return FLAC__STREAM_DECODER_READ_STATUS_ABORT;
 472         }
 473         ogg_bytes_read = ogg_bytes_to_read;
 474
 475         if(ogg_sync_wrote(&decoder->private_->ogg.sync_state, ogg_bytes_read) < 0) {
 476                 decoder->protected_->state = OggFLAC__STREAM_DECODER_READ_ERROR;
 477                 return FLAC__STREAM_DECODER_READ_STATUS_ABORT;
 478         }
 479
 480         *bytes = 0;
 481         while(ogg_sync_pageout(&decoder->private_->ogg.sync_state, &page) == 1) {
 482                 /* grab the serial number if necessary */
 483                 if(decoder->private_->ogg.need_serial_number) {
 484                         decoder->private_->ogg.stream_state.serialno = decoder->protected_->serial_number = ogg_page_serialno(&page);
 485                         decoder->private_->ogg.need_serial_number = false;
 486                 }
 487                 if(ogg_stream_pagein(&decoder->private_->ogg.stream_state, &page) == 0) {
 488                         ogg_packet packet;
 489
 490                         while(ogg_stream_packetout(&decoder->private_->ogg.stream_state, &packet) == 1) {
 491                                 memcpy(buffer, packet.packet, packet.bytes);
 492                                 *bytes += packet.bytes;
 493                                 buffer += packet.bytes;
 494                         }
 495                 } else {
 496                         decoder->protected_->state = OggFLAC__STREAM_DECODER_READ_ERROR;
 497                         return FLAC__STREAM_DECODER_READ_STATUS_ABORT;
 498                 }
 499         }
 500
 501         return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
 502 }
 503
 504 FLAC__StreamDecoderWriteStatus write_callback_(const FLAC__StreamDecoder *unused, const FLAC__Frame *frame, const FLAC__int32 * const buffer[], void *client_data)
 505 {
 506         OggFLAC__StreamDecoder *decoder = (OggFLAC__StreamDecoder*)client_data;
 507         (void)unused;
 508         return decoder->private_->write_callback(decoder, frame, buffer, decoder->private_->client_data);
 509 }
 510
 511 void metadata_callback_(const FLAC__StreamDecoder *unused, const FLAC__StreamMetadata *metadata, void *client_data)
 512 {
 513         OggFLAC__StreamDecoder *decoder = (OggFLAC__StreamDecoder*)client_data;
 514         (void)unused;
 515         decoder->private_->metadata_callback(decoder, metadata, decoder->private_->client_data);
 516 }
 517
 518 void error_callback_(const FLAC__StreamDecoder *unused, FLAC__StreamDecoderErrorStatus status, void *client_data)
 519 {
 520         OggFLAC__StreamDecoder *decoder = (OggFLAC__StreamDecoder*)client_data;
 521         (void)unused;
 522         decoder->private_->error_callback(decoder, status, decoder->private_->client_data);
 523 }