1 /* libFLAC - Free Lossless Audio Codec library
2  * Copyright (C) 2000-2009  Josh Coalson
3  * Copyright (C) 2011-2016  Xiph.Org Foundation
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  *
9  * - Redistributions of source code must retain the above copyright
10  * notice, this list of conditions and the following disclaimer.
11  *
12  * - 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  *
16  * - Neither the name of the Xiph.org Foundation nor the names of its
17  * contributors may be used to endorse or promote products derived from
18  * this software without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
23  * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
24  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
25  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
26  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
27  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
28  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
29  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
30  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #ifdef HAVE_CONFIG_H
34 #  include <config.h>
35 #endif
36 
37 #include <stdio.h>
38 #include <stdlib.h> /* for malloc() */
39 #include <string.h> /* for memset/memcpy() */
40 #include <sys/stat.h> /* for stat() */
41 #include <sys/types.h> /* for off_t */
42 #include "share/compat.h"
43 #include "FLAC/assert.h"
44 #include "share/alloc.h"
45 #include "protected/stream_decoder.h"
46 #include "private/bitreader.h"
47 #include "private/bitmath.h"
48 #include "private/cpu.h"
49 #include "private/crc.h"
50 #include "private/fixed.h"
51 #include "private/format.h"
52 #include "private/lpc.h"
53 #include "private/md5.h"
54 #include "private/memory.h"
55 #include "private/macros.h"
56 
57 
58 /* technically this should be in an "export.c" but this is convenient enough */
59 FLAC_API int FLAC_API_SUPPORTS_OGG_FLAC = FLAC__HAS_OGG;
60 
61 
62 /***********************************************************************
63  *
64  * Private static data
65  *
66  ***********************************************************************/
67 
68 static const FLAC__byte ID3V2_TAG_[3] = { 'I', 'D', '3' };
69 
70 /***********************************************************************
71  *
72  * Private class method prototypes
73  *
74  ***********************************************************************/
75 
76 static void set_defaults_(FLAC__StreamDecoder *decoder);
77 static FILE *get_binary_stdin_(void);
78 static FLAC__bool allocate_output_(FLAC__StreamDecoder *decoder, unsigned size, unsigned channels);
79 static FLAC__bool has_id_filtered_(FLAC__StreamDecoder *decoder, FLAC__byte *id);
80 static FLAC__bool find_metadata_(FLAC__StreamDecoder *decoder);
81 static FLAC__bool read_metadata_(FLAC__StreamDecoder *decoder);
82 static FLAC__bool read_metadata_streaminfo_(FLAC__StreamDecoder *decoder, FLAC__bool is_last, unsigned length);
83 static FLAC__bool read_metadata_seektable_(FLAC__StreamDecoder *decoder, FLAC__bool is_last, unsigned length);
84 static FLAC__bool read_metadata_vorbiscomment_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_VorbisComment *obj, unsigned length);
85 static FLAC__bool read_metadata_cuesheet_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_CueSheet *obj);
86 static FLAC__bool read_metadata_picture_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_Picture *obj);
87 static FLAC__bool skip_id3v2_tag_(FLAC__StreamDecoder *decoder);
88 static FLAC__bool frame_sync_(FLAC__StreamDecoder *decoder);
89 static FLAC__bool read_frame_(FLAC__StreamDecoder *decoder, FLAC__bool *got_a_frame, FLAC__bool do_full_decode);
90 static FLAC__bool read_frame_header_(FLAC__StreamDecoder *decoder);
91 static FLAC__bool read_subframe_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode);
92 static FLAC__bool read_subframe_constant_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode);
93 static FLAC__bool read_subframe_fixed_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, const unsigned order, FLAC__bool do_full_decode);
94 static FLAC__bool read_subframe_lpc_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, const unsigned order, FLAC__bool do_full_decode);
95 static FLAC__bool read_subframe_verbatim_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode);
96 static FLAC__bool read_residual_partitioned_rice_(FLAC__StreamDecoder *decoder, unsigned predictor_order, unsigned partition_order, FLAC__EntropyCodingMethod_PartitionedRiceContents *partitioned_rice_contents, FLAC__int32 *residual, FLAC__bool is_extended);
97 static FLAC__bool read_zero_padding_(FLAC__StreamDecoder *decoder);
98 static FLAC__bool read_callback_(FLAC__byte buffer[], size_t *bytes, void *client_data);
99 #if FLAC__HAS_OGG
100 static FLAC__StreamDecoderReadStatus read_callback_ogg_aspect_(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes);
101 static FLAC__OggDecoderAspectReadStatus read_callback_proxy_(const void *void_decoder, FLAC__byte buffer[], size_t *bytes, void *client_data);
102 #endif
103 static FLAC__StreamDecoderWriteStatus write_audio_frame_to_client_(FLAC__StreamDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[]);
104 static void send_error_to_client_(const FLAC__StreamDecoder *decoder, FLAC__StreamDecoderErrorStatus status);
105 static FLAC__bool seek_to_absolute_sample_(FLAC__StreamDecoder *decoder, FLAC__uint64 stream_length, FLAC__uint64 target_sample);
106 #if FLAC__HAS_OGG
107 static FLAC__bool seek_to_absolute_sample_ogg_(FLAC__StreamDecoder *decoder, FLAC__uint64 stream_length, FLAC__uint64 target_sample);
108 #endif
109 static FLAC__StreamDecoderReadStatus file_read_callback_(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes, void *client_data);
110 static FLAC__StreamDecoderSeekStatus file_seek_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 absolute_byte_offset, void *client_data);
111 static FLAC__StreamDecoderTellStatus file_tell_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 *absolute_byte_offset, void *client_data);
112 static FLAC__StreamDecoderLengthStatus file_length_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 *stream_length, void *client_data);
113 static FLAC__bool file_eof_callback_(const FLAC__StreamDecoder *decoder, void *client_data);
114 
115 /***********************************************************************
116  *
117  * Private class data
118  *
119  ***********************************************************************/
120 
121 typedef struct FLAC__StreamDecoderPrivate {
122 	FLAC__bool is_ogg;
123 	FLAC__StreamDecoderReadCallback read_callback;
124 	FLAC__StreamDecoderSeekCallback seek_callback;
125 	FLAC__StreamDecoderTellCallback tell_callback;
126 	FLAC__StreamDecoderLengthCallback length_callback;
127 	FLAC__StreamDecoderEofCallback eof_callback;
128 	FLAC__StreamDecoderWriteCallback write_callback;
129 	FLAC__StreamDecoderMetadataCallback metadata_callback;
130 	FLAC__StreamDecoderErrorCallback error_callback;
131 	/* generic 32-bit datapath: */
132 	void (*local_lpc_restore_signal)(const FLAC__int32 residual[], unsigned data_len, const FLAC__int32 qlp_coeff[], unsigned order, int lp_quantization, FLAC__int32 data[]);
133 	/* generic 64-bit datapath: */
134 	void (*local_lpc_restore_signal_64bit)(const FLAC__int32 residual[], unsigned data_len, const FLAC__int32 qlp_coeff[], unsigned order, int lp_quantization, FLAC__int32 data[]);
135 	/* for use when the signal is <= 16 bits-per-sample, or <= 15 bits-per-sample on a side channel (which requires 1 extra bit): */
136 	void (*local_lpc_restore_signal_16bit)(const FLAC__int32 residual[], unsigned data_len, const FLAC__int32 qlp_coeff[], unsigned order, int lp_quantization, FLAC__int32 data[]);
137 	void *client_data;
138 	FILE *file; /* only used if FLAC__stream_decoder_init_file()/FLAC__stream_decoder_init_file() called, else NULL */
139 	FLAC__BitReader *input;
140 	FLAC__int32 *output[FLAC__MAX_CHANNELS];
141 	FLAC__int32 *residual[FLAC__MAX_CHANNELS]; /* WATCHOUT: these are the aligned pointers; the real pointers that should be free()'d are residual_unaligned[] below */
142 	FLAC__EntropyCodingMethod_PartitionedRiceContents partitioned_rice_contents[FLAC__MAX_CHANNELS];
143 	unsigned output_capacity, output_channels;
144 	FLAC__uint32 fixed_block_size, next_fixed_block_size;
145 	FLAC__uint64 samples_decoded;
146 	FLAC__bool has_stream_info, has_seek_table;
147 	FLAC__StreamMetadata stream_info;
148 	FLAC__StreamMetadata seek_table;
149 	FLAC__bool metadata_filter[128]; /* MAGIC number 128 == total number of metadata block types == 1 << 7 */
150 	FLAC__byte *metadata_filter_ids;
151 	size_t metadata_filter_ids_count, metadata_filter_ids_capacity; /* units for both are IDs, not bytes */
152 	FLAC__Frame frame;
153 	FLAC__bool cached; /* true if there is a byte in lookahead */
154 	FLAC__CPUInfo cpuinfo;
155 	FLAC__byte header_warmup[2]; /* contains the sync code and reserved bits */
156 	FLAC__byte lookahead; /* temp storage when we need to look ahead one byte in the stream */
157 	/* unaligned (original) pointers to allocated data */
158 	FLAC__int32 *residual_unaligned[FLAC__MAX_CHANNELS];
159 	FLAC__bool do_md5_checking; /* initially gets protected_->md5_checking but is turned off after a seek or if the metadata has a zero MD5 */
160 	FLAC__bool internal_reset_hack; /* used only during init() so we can call reset to set up the decoder without rewinding the input */
161 	FLAC__bool is_seeking;
162 	FLAC__MD5Context md5context;
163 	FLAC__byte computed_md5sum[16]; /* this is the sum we computed from the decoded data */
164 	/* (the rest of these are only used for seeking) */
165 	FLAC__Frame last_frame; /* holds the info of the last frame we seeked to */
166 	FLAC__uint64 first_frame_offset; /* hint to the seek routine of where in the stream the first audio frame starts */
167 	FLAC__uint64 target_sample;
168 	unsigned unparseable_frame_count; /* used to tell whether we're decoding a future version of FLAC or just got a bad sync */
169 	FLAC__bool got_a_frame; /* hack needed in Ogg FLAC seek routine to check when process_single() actually writes a frame */
170 } FLAC__StreamDecoderPrivate;
171 
172 /***********************************************************************
173  *
174  * Public static class data
175  *
176  ***********************************************************************/
177 
178 FLAC_API const char * const FLAC__StreamDecoderStateString[] = {
179 	"FLAC__STREAM_DECODER_SEARCH_FOR_METADATA",
180 	"FLAC__STREAM_DECODER_READ_METADATA",
181 	"FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC",
182 	"FLAC__STREAM_DECODER_READ_FRAME",
183 	"FLAC__STREAM_DECODER_END_OF_STREAM",
184 	"FLAC__STREAM_DECODER_OGG_ERROR",
185 	"FLAC__STREAM_DECODER_SEEK_ERROR",
186 	"FLAC__STREAM_DECODER_ABORTED",
187 	"FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR",
188 	"FLAC__STREAM_DECODER_UNINITIALIZED"
189 };
190 
191 FLAC_API const char * const FLAC__StreamDecoderInitStatusString[] = {
192 	"FLAC__STREAM_DECODER_INIT_STATUS_OK",
193 	"FLAC__STREAM_DECODER_INIT_STATUS_UNSUPPORTED_CONTAINER",
194 	"FLAC__STREAM_DECODER_INIT_STATUS_INVALID_CALLBACKS",
195 	"FLAC__STREAM_DECODER_INIT_STATUS_MEMORY_ALLOCATION_ERROR",
196 	"FLAC__STREAM_DECODER_INIT_STATUS_ERROR_OPENING_FILE",
197 	"FLAC__STREAM_DECODER_INIT_STATUS_ALREADY_INITIALIZED"
198 };
199 
200 FLAC_API const char * const FLAC__StreamDecoderReadStatusString[] = {
201 	"FLAC__STREAM_DECODER_READ_STATUS_CONTINUE",
202 	"FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM",
203 	"FLAC__STREAM_DECODER_READ_STATUS_ABORT"
204 };
205 
206 FLAC_API const char * const FLAC__StreamDecoderSeekStatusString[] = {
207 	"FLAC__STREAM_DECODER_SEEK_STATUS_OK",
208 	"FLAC__STREAM_DECODER_SEEK_STATUS_ERROR",
209 	"FLAC__STREAM_DECODER_SEEK_STATUS_UNSUPPORTED"
210 };
211 
212 FLAC_API const char * const FLAC__StreamDecoderTellStatusString[] = {
213 	"FLAC__STREAM_DECODER_TELL_STATUS_OK",
214 	"FLAC__STREAM_DECODER_TELL_STATUS_ERROR",
215 	"FLAC__STREAM_DECODER_TELL_STATUS_UNSUPPORTED"
216 };
217 
218 FLAC_API const char * const FLAC__StreamDecoderLengthStatusString[] = {
219 	"FLAC__STREAM_DECODER_LENGTH_STATUS_OK",
220 	"FLAC__STREAM_DECODER_LENGTH_STATUS_ERROR",
221 	"FLAC__STREAM_DECODER_LENGTH_STATUS_UNSUPPORTED"
222 };
223 
224 FLAC_API const char * const FLAC__StreamDecoderWriteStatusString[] = {
225 	"FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE",
226 	"FLAC__STREAM_DECODER_WRITE_STATUS_ABORT"
227 };
228 
229 FLAC_API const char * const FLAC__StreamDecoderErrorStatusString[] = {
230 	"FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC",
231 	"FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER",
232 	"FLAC__STREAM_DECODER_ERROR_STATUS_FRAME_CRC_MISMATCH",
233 	"FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM"
234 };
235 
236 /***********************************************************************
237  *
238  * Class constructor/destructor
239  *
240  ***********************************************************************/
FLAC__stream_decoder_new(void)241 FLAC_API FLAC__StreamDecoder *FLAC__stream_decoder_new(void)
242 {
243 	FLAC__StreamDecoder *decoder;
244 	unsigned i;
245 
246 	FLAC__ASSERT(sizeof(int) >= 4); /* we want to die right away if this is not true */
247 
248 	decoder = calloc(1, sizeof(FLAC__StreamDecoder));
249 	if(decoder == 0) {
250 		return 0;
251 	}
252 
253 	decoder->protected_ = calloc(1, sizeof(FLAC__StreamDecoderProtected));
254 	if(decoder->protected_ == 0) {
255 		free(decoder);
256 		return 0;
257 	}
258 
259 	decoder->private_ = calloc(1, sizeof(FLAC__StreamDecoderPrivate));
260 	if(decoder->private_ == 0) {
261 		free(decoder->protected_);
262 		free(decoder);
263 		return 0;
264 	}
265 
266 	decoder->private_->input = FLAC__bitreader_new();
267 	if(decoder->private_->input == 0) {
268 		free(decoder->private_);
269 		free(decoder->protected_);
270 		free(decoder);
271 		return 0;
272 	}
273 
274 	decoder->private_->metadata_filter_ids_capacity = 16;
275 	if(0 == (decoder->private_->metadata_filter_ids = malloc((FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8) * decoder->private_->metadata_filter_ids_capacity))) {
276 		FLAC__bitreader_delete(decoder->private_->input);
277 		free(decoder->private_);
278 		free(decoder->protected_);
279 		free(decoder);
280 		return 0;
281 	}
282 
283 	for(i = 0; i < FLAC__MAX_CHANNELS; i++) {
284 		decoder->private_->output[i] = 0;
285 		decoder->private_->residual_unaligned[i] = decoder->private_->residual[i] = 0;
286 	}
287 
288 	decoder->private_->output_capacity = 0;
289 	decoder->private_->output_channels = 0;
290 	decoder->private_->has_seek_table = false;
291 
292 	for(i = 0; i < FLAC__MAX_CHANNELS; i++)
293 		FLAC__format_entropy_coding_method_partitioned_rice_contents_init(&decoder->private_->partitioned_rice_contents[i]);
294 
295 	decoder->private_->file = 0;
296 
297 	set_defaults_(decoder);
298 
299 	decoder->protected_->state = FLAC__STREAM_DECODER_UNINITIALIZED;
300 
301 	return decoder;
302 }
303 
FLAC__stream_decoder_delete(FLAC__StreamDecoder * decoder)304 FLAC_API void FLAC__stream_decoder_delete(FLAC__StreamDecoder *decoder)
305 {
306 	unsigned i;
307 
308 	if (decoder == NULL)
309 		return ;
310 
311 	FLAC__ASSERT(0 != decoder->protected_);
312 	FLAC__ASSERT(0 != decoder->private_);
313 	FLAC__ASSERT(0 != decoder->private_->input);
314 
315 	(void)FLAC__stream_decoder_finish(decoder);
316 
317 	if(0 != decoder->private_->metadata_filter_ids)
318 		free(decoder->private_->metadata_filter_ids);
319 
320 	FLAC__bitreader_delete(decoder->private_->input);
321 
322 	for(i = 0; i < FLAC__MAX_CHANNELS; i++)
323 		FLAC__format_entropy_coding_method_partitioned_rice_contents_clear(&decoder->private_->partitioned_rice_contents[i]);
324 
325 	free(decoder->private_);
326 	free(decoder->protected_);
327 	free(decoder);
328 }
329 
330 /***********************************************************************
331  *
332  * Public class methods
333  *
334  ***********************************************************************/
335 
init_stream_internal_(FLAC__StreamDecoder * decoder,FLAC__StreamDecoderReadCallback read_callback,FLAC__StreamDecoderSeekCallback seek_callback,FLAC__StreamDecoderTellCallback tell_callback,FLAC__StreamDecoderLengthCallback length_callback,FLAC__StreamDecoderEofCallback eof_callback,FLAC__StreamDecoderWriteCallback write_callback,FLAC__StreamDecoderMetadataCallback metadata_callback,FLAC__StreamDecoderErrorCallback error_callback,void * client_data,FLAC__bool is_ogg)336 static FLAC__StreamDecoderInitStatus init_stream_internal_(
337 	FLAC__StreamDecoder *decoder,
338 	FLAC__StreamDecoderReadCallback read_callback,
339 	FLAC__StreamDecoderSeekCallback seek_callback,
340 	FLAC__StreamDecoderTellCallback tell_callback,
341 	FLAC__StreamDecoderLengthCallback length_callback,
342 	FLAC__StreamDecoderEofCallback eof_callback,
343 	FLAC__StreamDecoderWriteCallback write_callback,
344 	FLAC__StreamDecoderMetadataCallback metadata_callback,
345 	FLAC__StreamDecoderErrorCallback error_callback,
346 	void *client_data,
347 	FLAC__bool is_ogg
348 )
349 {
350 	FLAC__ASSERT(0 != decoder);
351 
352 	if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
353 		return FLAC__STREAM_DECODER_INIT_STATUS_ALREADY_INITIALIZED;
354 
355 	if(FLAC__HAS_OGG == 0 && is_ogg)
356 		return FLAC__STREAM_DECODER_INIT_STATUS_UNSUPPORTED_CONTAINER;
357 
358 	if(
359 		0 == read_callback ||
360 		0 == write_callback ||
361 		0 == error_callback ||
362 		(seek_callback && (0 == tell_callback || 0 == length_callback || 0 == eof_callback))
363 	)
364 		return FLAC__STREAM_DECODER_INIT_STATUS_INVALID_CALLBACKS;
365 
366 #if FLAC__HAS_OGG
367 	decoder->private_->is_ogg = is_ogg;
368 	if(is_ogg && !FLAC__ogg_decoder_aspect_init(&decoder->protected_->ogg_decoder_aspect))
369 		return decoder->protected_->initstate = FLAC__STREAM_DECODER_INIT_STATUS_ERROR_OPENING_FILE;
370 #endif
371 
372 	/*
373 	 * get the CPU info and set the function pointers
374 	 */
375 	FLAC__cpu_info(&decoder->private_->cpuinfo);
376 	/* first default to the non-asm routines */
377 	decoder->private_->local_lpc_restore_signal = FLAC__lpc_restore_signal;
378 	decoder->private_->local_lpc_restore_signal_64bit = FLAC__lpc_restore_signal_wide;
379 	decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal;
380 	/* now override with asm where appropriate */
381 #ifndef FLAC__NO_ASM
382 	if(decoder->private_->cpuinfo.use_asm) {
383 #ifdef FLAC__CPU_IA32
384 		FLAC__ASSERT(decoder->private_->cpuinfo.type == FLAC__CPUINFO_TYPE_IA32);
385 #ifdef FLAC__HAS_NASM
386 		decoder->private_->local_lpc_restore_signal_64bit = FLAC__lpc_restore_signal_wide_asm_ia32; /* OPT_IA32: was really necessary for GCC < 4.9 */
387 		if(decoder->private_->cpuinfo.ia32.mmx) {
388 			decoder->private_->local_lpc_restore_signal = FLAC__lpc_restore_signal_asm_ia32;
389 			decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal_asm_ia32_mmx;
390 		}
391 		else {
392 			decoder->private_->local_lpc_restore_signal = FLAC__lpc_restore_signal_asm_ia32;
393 			decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal_asm_ia32;
394 		}
395 #endif
396 #if FLAC__HAS_X86INTRIN && ! defined FLAC__INTEGER_ONLY_LIBRARY
397 # if defined FLAC__SSE2_SUPPORTED && !defined FLAC__HAS_NASM /* OPT_SSE: not better than MMX asm */
398 		if(decoder->private_->cpuinfo.ia32.sse2) {
399 			decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal_16_intrin_sse2;
400 		}
401 # endif
402 # if defined FLAC__SSE4_1_SUPPORTED
403 		if(decoder->private_->cpuinfo.ia32.sse41) {
404 			decoder->private_->local_lpc_restore_signal_64bit = FLAC__lpc_restore_signal_wide_intrin_sse41;
405 		}
406 # endif
407 #endif
408 #elif defined FLAC__CPU_X86_64
409 		FLAC__ASSERT(decoder->private_->cpuinfo.type == FLAC__CPUINFO_TYPE_X86_64);
410 		/* No useful SSE optimizations yet */
411 #endif
412 	}
413 #endif
414 
415 	/* from here on, errors are fatal */
416 
417 	if(!FLAC__bitreader_init(decoder->private_->input, read_callback_, decoder)) {
418 		decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
419 		return FLAC__STREAM_DECODER_INIT_STATUS_MEMORY_ALLOCATION_ERROR;
420 	}
421 
422 	decoder->private_->read_callback = read_callback;
423 	decoder->private_->seek_callback = seek_callback;
424 	decoder->private_->tell_callback = tell_callback;
425 	decoder->private_->length_callback = length_callback;
426 	decoder->private_->eof_callback = eof_callback;
427 	decoder->private_->write_callback = write_callback;
428 	decoder->private_->metadata_callback = metadata_callback;
429 	decoder->private_->error_callback = error_callback;
430 	decoder->private_->client_data = client_data;
431 	decoder->private_->fixed_block_size = decoder->private_->next_fixed_block_size = 0;
432 	decoder->private_->samples_decoded = 0;
433 	decoder->private_->has_stream_info = false;
434 	decoder->private_->cached = false;
435 
436 	decoder->private_->do_md5_checking = decoder->protected_->md5_checking;
437 	decoder->private_->is_seeking = false;
438 
439 	decoder->private_->internal_reset_hack = true; /* so the following reset does not try to rewind the input */
440 	if(!FLAC__stream_decoder_reset(decoder)) {
441 		/* above call sets the state for us */
442 		return FLAC__STREAM_DECODER_INIT_STATUS_MEMORY_ALLOCATION_ERROR;
443 	}
444 
445 	return FLAC__STREAM_DECODER_INIT_STATUS_OK;
446 }
447 
FLAC__stream_decoder_init_stream(FLAC__StreamDecoder * decoder,FLAC__StreamDecoderReadCallback read_callback,FLAC__StreamDecoderSeekCallback seek_callback,FLAC__StreamDecoderTellCallback tell_callback,FLAC__StreamDecoderLengthCallback length_callback,FLAC__StreamDecoderEofCallback eof_callback,FLAC__StreamDecoderWriteCallback write_callback,FLAC__StreamDecoderMetadataCallback metadata_callback,FLAC__StreamDecoderErrorCallback error_callback,void * client_data)448 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_stream(
449 	FLAC__StreamDecoder *decoder,
450 	FLAC__StreamDecoderReadCallback read_callback,
451 	FLAC__StreamDecoderSeekCallback seek_callback,
452 	FLAC__StreamDecoderTellCallback tell_callback,
453 	FLAC__StreamDecoderLengthCallback length_callback,
454 	FLAC__StreamDecoderEofCallback eof_callback,
455 	FLAC__StreamDecoderWriteCallback write_callback,
456 	FLAC__StreamDecoderMetadataCallback metadata_callback,
457 	FLAC__StreamDecoderErrorCallback error_callback,
458 	void *client_data
459 )
460 {
461 	return init_stream_internal_(
462 		decoder,
463 		read_callback,
464 		seek_callback,
465 		tell_callback,
466 		length_callback,
467 		eof_callback,
468 		write_callback,
469 		metadata_callback,
470 		error_callback,
471 		client_data,
472 		/*is_ogg=*/false
473 	);
474 }
475 
FLAC__stream_decoder_init_ogg_stream(FLAC__StreamDecoder * decoder,FLAC__StreamDecoderReadCallback read_callback,FLAC__StreamDecoderSeekCallback seek_callback,FLAC__StreamDecoderTellCallback tell_callback,FLAC__StreamDecoderLengthCallback length_callback,FLAC__StreamDecoderEofCallback eof_callback,FLAC__StreamDecoderWriteCallback write_callback,FLAC__StreamDecoderMetadataCallback metadata_callback,FLAC__StreamDecoderErrorCallback error_callback,void * client_data)476 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_ogg_stream(
477 	FLAC__StreamDecoder *decoder,
478 	FLAC__StreamDecoderReadCallback read_callback,
479 	FLAC__StreamDecoderSeekCallback seek_callback,
480 	FLAC__StreamDecoderTellCallback tell_callback,
481 	FLAC__StreamDecoderLengthCallback length_callback,
482 	FLAC__StreamDecoderEofCallback eof_callback,
483 	FLAC__StreamDecoderWriteCallback write_callback,
484 	FLAC__StreamDecoderMetadataCallback metadata_callback,
485 	FLAC__StreamDecoderErrorCallback error_callback,
486 	void *client_data
487 )
488 {
489 	return init_stream_internal_(
490 		decoder,
491 		read_callback,
492 		seek_callback,
493 		tell_callback,
494 		length_callback,
495 		eof_callback,
496 		write_callback,
497 		metadata_callback,
498 		error_callback,
499 		client_data,
500 		/*is_ogg=*/true
501 	);
502 }
503 
init_FILE_internal_(FLAC__StreamDecoder * decoder,FILE * file,FLAC__StreamDecoderWriteCallback write_callback,FLAC__StreamDecoderMetadataCallback metadata_callback,FLAC__StreamDecoderErrorCallback error_callback,void * client_data,FLAC__bool is_ogg)504 static FLAC__StreamDecoderInitStatus init_FILE_internal_(
505 	FLAC__StreamDecoder *decoder,
506 	FILE *file,
507 	FLAC__StreamDecoderWriteCallback write_callback,
508 	FLAC__StreamDecoderMetadataCallback metadata_callback,
509 	FLAC__StreamDecoderErrorCallback error_callback,
510 	void *client_data,
511 	FLAC__bool is_ogg
512 )
513 {
514 	FLAC__ASSERT(0 != decoder);
515 	FLAC__ASSERT(0 != file);
516 
517 	if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
518 		return decoder->protected_->initstate = FLAC__STREAM_DECODER_INIT_STATUS_ALREADY_INITIALIZED;
519 
520 	if(0 == write_callback || 0 == error_callback)
521 		return decoder->protected_->initstate = FLAC__STREAM_DECODER_INIT_STATUS_INVALID_CALLBACKS;
522 
523 	/*
524 	 * To make sure that our file does not go unclosed after an error, we
525 	 * must assign the FILE pointer before any further error can occur in
526 	 * this routine.
527 	 */
528 	if(file == stdin)
529 		file = get_binary_stdin_(); /* just to be safe */
530 
531 	decoder->private_->file = file;
532 
533 	return init_stream_internal_(
534 		decoder,
535 		file_read_callback_,
536 		decoder->private_->file == stdin? 0: file_seek_callback_,
537 		decoder->private_->file == stdin? 0: file_tell_callback_,
538 		decoder->private_->file == stdin? 0: file_length_callback_,
539 		file_eof_callback_,
540 		write_callback,
541 		metadata_callback,
542 		error_callback,
543 		client_data,
544 		is_ogg
545 	);
546 }
547 
FLAC__stream_decoder_init_FILE(FLAC__StreamDecoder * decoder,FILE * file,FLAC__StreamDecoderWriteCallback write_callback,FLAC__StreamDecoderMetadataCallback metadata_callback,FLAC__StreamDecoderErrorCallback error_callback,void * client_data)548 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_FILE(
549 	FLAC__StreamDecoder *decoder,
550 	FILE *file,
551 	FLAC__StreamDecoderWriteCallback write_callback,
552 	FLAC__StreamDecoderMetadataCallback metadata_callback,
553 	FLAC__StreamDecoderErrorCallback error_callback,
554 	void *client_data
555 )
556 {
557 	return init_FILE_internal_(decoder, file, write_callback, metadata_callback, error_callback, client_data, /*is_ogg=*/false);
558 }
559 
FLAC__stream_decoder_init_ogg_FILE(FLAC__StreamDecoder * decoder,FILE * file,FLAC__StreamDecoderWriteCallback write_callback,FLAC__StreamDecoderMetadataCallback metadata_callback,FLAC__StreamDecoderErrorCallback error_callback,void * client_data)560 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_ogg_FILE(
561 	FLAC__StreamDecoder *decoder,
562 	FILE *file,
563 	FLAC__StreamDecoderWriteCallback write_callback,
564 	FLAC__StreamDecoderMetadataCallback metadata_callback,
565 	FLAC__StreamDecoderErrorCallback error_callback,
566 	void *client_data
567 )
568 {
569 	return init_FILE_internal_(decoder, file, write_callback, metadata_callback, error_callback, client_data, /*is_ogg=*/true);
570 }
571 
init_file_internal_(FLAC__StreamDecoder * decoder,const char * filename,FLAC__StreamDecoderWriteCallback write_callback,FLAC__StreamDecoderMetadataCallback metadata_callback,FLAC__StreamDecoderErrorCallback error_callback,void * client_data,FLAC__bool is_ogg)572 static FLAC__StreamDecoderInitStatus init_file_internal_(
573 	FLAC__StreamDecoder *decoder,
574 	const char *filename,
575 	FLAC__StreamDecoderWriteCallback write_callback,
576 	FLAC__StreamDecoderMetadataCallback metadata_callback,
577 	FLAC__StreamDecoderErrorCallback error_callback,
578 	void *client_data,
579 	FLAC__bool is_ogg
580 )
581 {
582 	FILE *file;
583 
584 	FLAC__ASSERT(0 != decoder);
585 
586 	/*
587 	 * To make sure that our file does not go unclosed after an error, we
588 	 * have to do the same entrance checks here that are later performed
589 	 * in FLAC__stream_decoder_init_FILE() before the FILE* is assigned.
590 	 */
591 	if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
592 		return decoder->protected_->initstate = FLAC__STREAM_DECODER_INIT_STATUS_ALREADY_INITIALIZED;
593 
594 	if(0 == write_callback || 0 == error_callback)
595 		return decoder->protected_->initstate = FLAC__STREAM_DECODER_INIT_STATUS_INVALID_CALLBACKS;
596 
597 	file = filename? flac_fopen(filename, "rb") : stdin;
598 
599 	if(0 == file)
600 		return FLAC__STREAM_DECODER_INIT_STATUS_ERROR_OPENING_FILE;
601 
602 	return init_FILE_internal_(decoder, file, write_callback, metadata_callback, error_callback, client_data, is_ogg);
603 }
604 
FLAC__stream_decoder_init_file(FLAC__StreamDecoder * decoder,const char * filename,FLAC__StreamDecoderWriteCallback write_callback,FLAC__StreamDecoderMetadataCallback metadata_callback,FLAC__StreamDecoderErrorCallback error_callback,void * client_data)605 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_file(
606 	FLAC__StreamDecoder *decoder,
607 	const char *filename,
608 	FLAC__StreamDecoderWriteCallback write_callback,
609 	FLAC__StreamDecoderMetadataCallback metadata_callback,
610 	FLAC__StreamDecoderErrorCallback error_callback,
611 	void *client_data
612 )
613 {
614 	return init_file_internal_(decoder, filename, write_callback, metadata_callback, error_callback, client_data, /*is_ogg=*/false);
615 }
616 
FLAC__stream_decoder_init_ogg_file(FLAC__StreamDecoder * decoder,const char * filename,FLAC__StreamDecoderWriteCallback write_callback,FLAC__StreamDecoderMetadataCallback metadata_callback,FLAC__StreamDecoderErrorCallback error_callback,void * client_data)617 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_ogg_file(
618 	FLAC__StreamDecoder *decoder,
619 	const char *filename,
620 	FLAC__StreamDecoderWriteCallback write_callback,
621 	FLAC__StreamDecoderMetadataCallback metadata_callback,
622 	FLAC__StreamDecoderErrorCallback error_callback,
623 	void *client_data
624 )
625 {
626 	return init_file_internal_(decoder, filename, write_callback, metadata_callback, error_callback, client_data, /*is_ogg=*/true);
627 }
628 
FLAC__stream_decoder_finish(FLAC__StreamDecoder * decoder)629 FLAC_API FLAC__bool FLAC__stream_decoder_finish(FLAC__StreamDecoder *decoder)
630 {
631 	FLAC__bool md5_failed = false;
632 	unsigned i;
633 
634 	FLAC__ASSERT(0 != decoder);
635 	FLAC__ASSERT(0 != decoder->private_);
636 	FLAC__ASSERT(0 != decoder->protected_);
637 
638 	if(decoder->protected_->state == FLAC__STREAM_DECODER_UNINITIALIZED)
639 		return true;
640 
641 	/* see the comment in FLAC__stream_decoder_reset() as to why we
642 	 * always call FLAC__MD5Final()
643 	 */
644 	FLAC__MD5Final(decoder->private_->computed_md5sum, &decoder->private_->md5context);
645 
646 	free(decoder->private_->seek_table.data.seek_table.points);
647 	decoder->private_->seek_table.data.seek_table.points = 0;
648 	decoder->private_->has_seek_table = false;
649 
650 	FLAC__bitreader_free(decoder->private_->input);
651 	for(i = 0; i < FLAC__MAX_CHANNELS; i++) {
652 		/* WATCHOUT:
653 		 * FLAC__lpc_restore_signal_asm_ia32_mmx() requires that the
654 		 * output arrays have a buffer of up to 3 zeroes in front
655 		 * (at negative indices) for alignment purposes; we use 4
656 		 * to keep the data well-aligned.
657 		 */
658 		if(0 != decoder->private_->output[i]) {
659 			free(decoder->private_->output[i]-4);
660 			decoder->private_->output[i] = 0;
661 		}
662 		if(0 != decoder->private_->residual_unaligned[i]) {
663 			free(decoder->private_->residual_unaligned[i]);
664 			decoder->private_->residual_unaligned[i] = decoder->private_->residual[i] = 0;
665 		}
666 	}
667 	decoder->private_->output_capacity = 0;
668 	decoder->private_->output_channels = 0;
669 
670 #if FLAC__HAS_OGG
671 	if(decoder->private_->is_ogg)
672 		FLAC__ogg_decoder_aspect_finish(&decoder->protected_->ogg_decoder_aspect);
673 #endif
674 
675 	if(0 != decoder->private_->file) {
676 		if(decoder->private_->file != stdin)
677 			fclose(decoder->private_->file);
678 		decoder->private_->file = 0;
679 	}
680 
681 	if(decoder->private_->do_md5_checking) {
682 		if(memcmp(decoder->private_->stream_info.data.stream_info.md5sum, decoder->private_->computed_md5sum, 16))
683 			md5_failed = true;
684 	}
685 	decoder->private_->is_seeking = false;
686 
687 	set_defaults_(decoder);
688 
689 	decoder->protected_->state = FLAC__STREAM_DECODER_UNINITIALIZED;
690 
691 	return !md5_failed;
692 }
693 
FLAC__stream_decoder_set_ogg_serial_number(FLAC__StreamDecoder * decoder,long value)694 FLAC_API FLAC__bool FLAC__stream_decoder_set_ogg_serial_number(FLAC__StreamDecoder *decoder, long value)
695 {
696 	FLAC__ASSERT(0 != decoder);
697 	FLAC__ASSERT(0 != decoder->private_);
698 	FLAC__ASSERT(0 != decoder->protected_);
699 	if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
700 		return false;
701 #if FLAC__HAS_OGG
702 	/* can't check decoder->private_->is_ogg since that's not set until init time */
703 	FLAC__ogg_decoder_aspect_set_serial_number(&decoder->protected_->ogg_decoder_aspect, value);
704 	return true;
705 #else
706 	(void)value;
707 	return false;
708 #endif
709 }
710 
FLAC__stream_decoder_set_md5_checking(FLAC__StreamDecoder * decoder,FLAC__bool value)711 FLAC_API FLAC__bool FLAC__stream_decoder_set_md5_checking(FLAC__StreamDecoder *decoder, FLAC__bool value)
712 {
713 	FLAC__ASSERT(0 != decoder);
714 	FLAC__ASSERT(0 != decoder->protected_);
715 	if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
716 		return false;
717 	decoder->protected_->md5_checking = value;
718 	return true;
719 }
720 
FLAC__stream_decoder_set_metadata_respond(FLAC__StreamDecoder * decoder,FLAC__MetadataType type)721 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond(FLAC__StreamDecoder *decoder, FLAC__MetadataType type)
722 {
723 	FLAC__ASSERT(0 != decoder);
724 	FLAC__ASSERT(0 != decoder->private_);
725 	FLAC__ASSERT(0 != decoder->protected_);
726 	FLAC__ASSERT((unsigned)type <= FLAC__MAX_METADATA_TYPE_CODE);
727 	/* double protection */
728 	if((unsigned)type > FLAC__MAX_METADATA_TYPE_CODE)
729 		return false;
730 	if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
731 		return false;
732 	decoder->private_->metadata_filter[type] = true;
733 	if(type == FLAC__METADATA_TYPE_APPLICATION)
734 		decoder->private_->metadata_filter_ids_count = 0;
735 	return true;
736 }
737 
FLAC__stream_decoder_set_metadata_respond_application(FLAC__StreamDecoder * decoder,const FLAC__byte id[4])738 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond_application(FLAC__StreamDecoder *decoder, const FLAC__byte id[4])
739 {
740 	FLAC__ASSERT(0 != decoder);
741 	FLAC__ASSERT(0 != decoder->private_);
742 	FLAC__ASSERT(0 != decoder->protected_);
743 	FLAC__ASSERT(0 != id);
744 	if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
745 		return false;
746 
747 	if(decoder->private_->metadata_filter[FLAC__METADATA_TYPE_APPLICATION])
748 		return true;
749 
750 	FLAC__ASSERT(0 != decoder->private_->metadata_filter_ids);
751 
752 	if(decoder->private_->metadata_filter_ids_count == decoder->private_->metadata_filter_ids_capacity) {
753 		if(0 == (decoder->private_->metadata_filter_ids = safe_realloc_mul_2op_(decoder->private_->metadata_filter_ids, decoder->private_->metadata_filter_ids_capacity, /*times*/2))) {
754 			decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
755 			return false;
756 		}
757 		decoder->private_->metadata_filter_ids_capacity *= 2;
758 	}
759 
760 	memcpy(decoder->private_->metadata_filter_ids + decoder->private_->metadata_filter_ids_count * (FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8), id, (FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8));
761 	decoder->private_->metadata_filter_ids_count++;
762 
763 	return true;
764 }
765 
FLAC__stream_decoder_set_metadata_respond_all(FLAC__StreamDecoder * decoder)766 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond_all(FLAC__StreamDecoder *decoder)
767 {
768 	unsigned i;
769 	FLAC__ASSERT(0 != decoder);
770 	FLAC__ASSERT(0 != decoder->private_);
771 	FLAC__ASSERT(0 != decoder->protected_);
772 	if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
773 		return false;
774 	for(i = 0; i < sizeof(decoder->private_->metadata_filter) / sizeof(decoder->private_->metadata_filter[0]); i++)
775 		decoder->private_->metadata_filter[i] = true;
776 	decoder->private_->metadata_filter_ids_count = 0;
777 	return true;
778 }
779 
FLAC__stream_decoder_set_metadata_ignore(FLAC__StreamDecoder * decoder,FLAC__MetadataType type)780 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore(FLAC__StreamDecoder *decoder, FLAC__MetadataType type)
781 {
782 	FLAC__ASSERT(0 != decoder);
783 	FLAC__ASSERT(0 != decoder->private_);
784 	FLAC__ASSERT(0 != decoder->protected_);
785 	FLAC__ASSERT((unsigned)type <= FLAC__MAX_METADATA_TYPE_CODE);
786 	/* double protection */
787 	if((unsigned)type > FLAC__MAX_METADATA_TYPE_CODE)
788 		return false;
789 	if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
790 		return false;
791 	decoder->private_->metadata_filter[type] = false;
792 	if(type == FLAC__METADATA_TYPE_APPLICATION)
793 		decoder->private_->metadata_filter_ids_count = 0;
794 	return true;
795 }
796 
FLAC__stream_decoder_set_metadata_ignore_application(FLAC__StreamDecoder * decoder,const FLAC__byte id[4])797 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore_application(FLAC__StreamDecoder *decoder, const FLAC__byte id[4])
798 {
799 	FLAC__ASSERT(0 != decoder);
800 	FLAC__ASSERT(0 != decoder->private_);
801 	FLAC__ASSERT(0 != decoder->protected_);
802 	FLAC__ASSERT(0 != id);
803 	if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
804 		return false;
805 
806 	if(!decoder->private_->metadata_filter[FLAC__METADATA_TYPE_APPLICATION])
807 		return true;
808 
809 	FLAC__ASSERT(0 != decoder->private_->metadata_filter_ids);
810 
811 	if(decoder->private_->metadata_filter_ids_count == decoder->private_->metadata_filter_ids_capacity) {
812 		if(0 == (decoder->private_->metadata_filter_ids = safe_realloc_mul_2op_(decoder->private_->metadata_filter_ids, decoder->private_->metadata_filter_ids_capacity, /*times*/2))) {
813 			decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
814 			return false;
815 		}
816 		decoder->private_->metadata_filter_ids_capacity *= 2;
817 	}
818 
819 	memcpy(decoder->private_->metadata_filter_ids + decoder->private_->metadata_filter_ids_count * (FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8), id, (FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8));
820 	decoder->private_->metadata_filter_ids_count++;
821 
822 	return true;
823 }
824 
FLAC__stream_decoder_set_metadata_ignore_all(FLAC__StreamDecoder * decoder)825 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore_all(FLAC__StreamDecoder *decoder)
826 {
827 	FLAC__ASSERT(0 != decoder);
828 	FLAC__ASSERT(0 != decoder->private_);
829 	FLAC__ASSERT(0 != decoder->protected_);
830 	if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
831 		return false;
832 	memset(decoder->private_->metadata_filter, 0, sizeof(decoder->private_->metadata_filter));
833 	decoder->private_->metadata_filter_ids_count = 0;
834 	return true;
835 }
836 
FLAC__stream_decoder_get_state(const FLAC__StreamDecoder * decoder)837 FLAC_API FLAC__StreamDecoderState FLAC__stream_decoder_get_state(const FLAC__StreamDecoder *decoder)
838 {
839 	FLAC__ASSERT(0 != decoder);
840 	FLAC__ASSERT(0 != decoder->protected_);
841 	return decoder->protected_->state;
842 }
843 
FLAC__stream_decoder_get_resolved_state_string(const FLAC__StreamDecoder * decoder)844 FLAC_API const char *FLAC__stream_decoder_get_resolved_state_string(const FLAC__StreamDecoder *decoder)
845 {
846 	return FLAC__StreamDecoderStateString[decoder->protected_->state];
847 }
848 
FLAC__stream_decoder_get_md5_checking(const FLAC__StreamDecoder * decoder)849 FLAC_API FLAC__bool FLAC__stream_decoder_get_md5_checking(const FLAC__StreamDecoder *decoder)
850 {
851 	FLAC__ASSERT(0 != decoder);
852 	FLAC__ASSERT(0 != decoder->protected_);
853 	return decoder->protected_->md5_checking;
854 }
855 
FLAC__stream_decoder_get_total_samples(const FLAC__StreamDecoder * decoder)856 FLAC_API FLAC__uint64 FLAC__stream_decoder_get_total_samples(const FLAC__StreamDecoder *decoder)
857 {
858 	FLAC__ASSERT(0 != decoder);
859 	FLAC__ASSERT(0 != decoder->protected_);
860 	return decoder->private_->has_stream_info? decoder->private_->stream_info.data.stream_info.total_samples : 0;
861 }
862 
FLAC__stream_decoder_get_channels(const FLAC__StreamDecoder * decoder)863 FLAC_API unsigned FLAC__stream_decoder_get_channels(const FLAC__StreamDecoder *decoder)
864 {
865 	FLAC__ASSERT(0 != decoder);
866 	FLAC__ASSERT(0 != decoder->protected_);
867 	return decoder->protected_->channels;
868 }
869 
FLAC__stream_decoder_get_channel_assignment(const FLAC__StreamDecoder * decoder)870 FLAC_API FLAC__ChannelAssignment FLAC__stream_decoder_get_channel_assignment(const FLAC__StreamDecoder *decoder)
871 {
872 	FLAC__ASSERT(0 != decoder);
873 	FLAC__ASSERT(0 != decoder->protected_);
874 	return decoder->protected_->channel_assignment;
875 }
876 
FLAC__stream_decoder_get_bits_per_sample(const FLAC__StreamDecoder * decoder)877 FLAC_API unsigned FLAC__stream_decoder_get_bits_per_sample(const FLAC__StreamDecoder *decoder)
878 {
879 	FLAC__ASSERT(0 != decoder);
880 	FLAC__ASSERT(0 != decoder->protected_);
881 	return decoder->protected_->bits_per_sample;
882 }
883 
FLAC__stream_decoder_get_sample_rate(const FLAC__StreamDecoder * decoder)884 FLAC_API unsigned FLAC__stream_decoder_get_sample_rate(const FLAC__StreamDecoder *decoder)
885 {
886 	FLAC__ASSERT(0 != decoder);
887 	FLAC__ASSERT(0 != decoder->protected_);
888 	return decoder->protected_->sample_rate;
889 }
890 
FLAC__stream_decoder_get_blocksize(const FLAC__StreamDecoder * decoder)891 FLAC_API unsigned FLAC__stream_decoder_get_blocksize(const FLAC__StreamDecoder *decoder)
892 {
893 	FLAC__ASSERT(0 != decoder);
894 	FLAC__ASSERT(0 != decoder->protected_);
895 	return decoder->protected_->blocksize;
896 }
897 
FLAC__stream_decoder_get_decode_position(const FLAC__StreamDecoder * decoder,FLAC__uint64 * position)898 FLAC_API FLAC__bool FLAC__stream_decoder_get_decode_position(const FLAC__StreamDecoder *decoder, FLAC__uint64 *position)
899 {
900 	FLAC__ASSERT(0 != decoder);
901 	FLAC__ASSERT(0 != decoder->private_);
902 	FLAC__ASSERT(0 != position);
903 
904 	if(FLAC__HAS_OGG && decoder->private_->is_ogg)
905 		return false;
906 
907 	if(0 == decoder->private_->tell_callback)
908 		return false;
909 	if(decoder->private_->tell_callback(decoder, position, decoder->private_->client_data) != FLAC__STREAM_DECODER_TELL_STATUS_OK)
910 		return false;
911 	/* should never happen since all FLAC frames and metadata blocks are byte aligned, but check just in case */
912 	if(!FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input))
913 		return false;
914 	FLAC__ASSERT(*position >= FLAC__stream_decoder_get_input_bytes_unconsumed(decoder));
915 	*position -= FLAC__stream_decoder_get_input_bytes_unconsumed(decoder);
916 	return true;
917 }
918 
FLAC__stream_decoder_flush(FLAC__StreamDecoder * decoder)919 FLAC_API FLAC__bool FLAC__stream_decoder_flush(FLAC__StreamDecoder *decoder)
920 {
921 	FLAC__ASSERT(0 != decoder);
922 	FLAC__ASSERT(0 != decoder->private_);
923 	FLAC__ASSERT(0 != decoder->protected_);
924 
925 	if(!decoder->private_->internal_reset_hack && decoder->protected_->state == FLAC__STREAM_DECODER_UNINITIALIZED)
926 		return false;
927 
928 	decoder->private_->samples_decoded = 0;
929 	decoder->private_->do_md5_checking = false;
930 
931 #if FLAC__HAS_OGG
932 	if(decoder->private_->is_ogg)
933 		FLAC__ogg_decoder_aspect_flush(&decoder->protected_->ogg_decoder_aspect);
934 #endif
935 
936 	if(!FLAC__bitreader_clear(decoder->private_->input)) {
937 		decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
938 		return false;
939 	}
940 	decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
941 
942 	return true;
943 }
944 
FLAC__stream_decoder_reset(FLAC__StreamDecoder * decoder)945 FLAC_API FLAC__bool FLAC__stream_decoder_reset(FLAC__StreamDecoder *decoder)
946 {
947 	FLAC__ASSERT(0 != decoder);
948 	FLAC__ASSERT(0 != decoder->private_);
949 	FLAC__ASSERT(0 != decoder->protected_);
950 
951 	if(!FLAC__stream_decoder_flush(decoder)) {
952 		/* above call sets the state for us */
953 		return false;
954 	}
955 
956 #if FLAC__HAS_OGG
957 	/*@@@ could go in !internal_reset_hack block below */
958 	if(decoder->private_->is_ogg)
959 		FLAC__ogg_decoder_aspect_reset(&decoder->protected_->ogg_decoder_aspect);
960 #endif
961 
962 	/* Rewind if necessary.  If FLAC__stream_decoder_init() is calling us,
963 	 * (internal_reset_hack) don't try to rewind since we are already at
964 	 * the beginning of the stream and don't want to fail if the input is
965 	 * not seekable.
966 	 */
967 	if(!decoder->private_->internal_reset_hack) {
968 		if(decoder->private_->file == stdin)
969 			return false; /* can't rewind stdin, reset fails */
970 		if(decoder->private_->seek_callback && decoder->private_->seek_callback(decoder, 0, decoder->private_->client_data) == FLAC__STREAM_DECODER_SEEK_STATUS_ERROR)
971 			return false; /* seekable and seek fails, reset fails */
972 	}
973 	else
974 		decoder->private_->internal_reset_hack = false;
975 
976 	decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_METADATA;
977 
978 	decoder->private_->has_stream_info = false;
979 
980 	free(decoder->private_->seek_table.data.seek_table.points);
981 	decoder->private_->seek_table.data.seek_table.points = 0;
982 	decoder->private_->has_seek_table = false;
983 
984 	decoder->private_->do_md5_checking = decoder->protected_->md5_checking;
985 	/*
986 	 * This goes in reset() and not flush() because according to the spec, a
987 	 * fixed-blocksize stream must stay that way through the whole stream.
988 	 */
989 	decoder->private_->fixed_block_size = decoder->private_->next_fixed_block_size = 0;
990 
991 	/* We initialize the FLAC__MD5Context even though we may never use it.  This
992 	 * is because md5 checking may be turned on to start and then turned off if
993 	 * a seek occurs.  So we init the context here and finalize it in
994 	 * FLAC__stream_decoder_finish() to make sure things are always cleaned up
995 	 * properly.
996 	 */
997 	FLAC__MD5Init(&decoder->private_->md5context);
998 
999 	decoder->private_->first_frame_offset = 0;
1000 	decoder->private_->unparseable_frame_count = 0;
1001 
1002 	return true;
1003 }
1004 
FLAC__stream_decoder_process_single(FLAC__StreamDecoder * decoder)1005 FLAC_API FLAC__bool FLAC__stream_decoder_process_single(FLAC__StreamDecoder *decoder)
1006 {
1007 	FLAC__bool got_a_frame;
1008 	FLAC__ASSERT(0 != decoder);
1009 	FLAC__ASSERT(0 != decoder->protected_);
1010 
1011 	while(1) {
1012 		switch(decoder->protected_->state) {
1013 			case FLAC__STREAM_DECODER_SEARCH_FOR_METADATA:
1014 				if(!find_metadata_(decoder))
1015 					return false; /* above function sets the status for us */
1016 				break;
1017 			case FLAC__STREAM_DECODER_READ_METADATA:
1018 				if(!read_metadata_(decoder))
1019 					return false; /* above function sets the status for us */
1020 				else
1021 					return true;
1022 			case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
1023 				if(!frame_sync_(decoder))
1024 					return true; /* above function sets the status for us */
1025 				break;
1026 			case FLAC__STREAM_DECODER_READ_FRAME:
1027 				if(!read_frame_(decoder, &got_a_frame, /*do_full_decode=*/true))
1028 					return false; /* above function sets the status for us */
1029 				if(got_a_frame)
1030 					return true; /* above function sets the status for us */
1031 				break;
1032 			case FLAC__STREAM_DECODER_END_OF_STREAM:
1033 			case FLAC__STREAM_DECODER_ABORTED:
1034 				return true;
1035 			default:
1036 				FLAC__ASSERT(0);
1037 				return false;
1038 		}
1039 	}
1040 }
1041 
FLAC__stream_decoder_process_until_end_of_metadata(FLAC__StreamDecoder * decoder)1042 FLAC_API FLAC__bool FLAC__stream_decoder_process_until_end_of_metadata(FLAC__StreamDecoder *decoder)
1043 {
1044 	FLAC__ASSERT(0 != decoder);
1045 	FLAC__ASSERT(0 != decoder->protected_);
1046 
1047 	while(1) {
1048 		switch(decoder->protected_->state) {
1049 			case FLAC__STREAM_DECODER_SEARCH_FOR_METADATA:
1050 				if(!find_metadata_(decoder))
1051 					return false; /* above function sets the status for us */
1052 				break;
1053 			case FLAC__STREAM_DECODER_READ_METADATA:
1054 				if(!read_metadata_(decoder))
1055 					return false; /* above function sets the status for us */
1056 				break;
1057 			case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
1058 			case FLAC__STREAM_DECODER_READ_FRAME:
1059 			case FLAC__STREAM_DECODER_END_OF_STREAM:
1060 			case FLAC__STREAM_DECODER_ABORTED:
1061 				return true;
1062 			default:
1063 				FLAC__ASSERT(0);
1064 				return false;
1065 		}
1066 	}
1067 }
1068 
FLAC__stream_decoder_process_until_end_of_stream(FLAC__StreamDecoder * decoder)1069 FLAC_API FLAC__bool FLAC__stream_decoder_process_until_end_of_stream(FLAC__StreamDecoder *decoder)
1070 {
1071 	FLAC__bool dummy;
1072 	FLAC__ASSERT(0 != decoder);
1073 	FLAC__ASSERT(0 != decoder->protected_);
1074 
1075 	while(1) {
1076 		switch(decoder->protected_->state) {
1077 			case FLAC__STREAM_DECODER_SEARCH_FOR_METADATA:
1078 				if(!find_metadata_(decoder))
1079 					return false; /* above function sets the status for us */
1080 				break;
1081 			case FLAC__STREAM_DECODER_READ_METADATA:
1082 				if(!read_metadata_(decoder))
1083 					return false; /* above function sets the status for us */
1084 				break;
1085 			case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
1086 				if(!frame_sync_(decoder))
1087 					return true; /* above function sets the status for us */
1088 				break;
1089 			case FLAC__STREAM_DECODER_READ_FRAME:
1090 				if(!read_frame_(decoder, &dummy, /*do_full_decode=*/true))
1091 					return false; /* above function sets the status for us */
1092 				break;
1093 			case FLAC__STREAM_DECODER_END_OF_STREAM:
1094 			case FLAC__STREAM_DECODER_ABORTED:
1095 				return true;
1096 			default:
1097 				FLAC__ASSERT(0);
1098 				return false;
1099 		}
1100 	}
1101 }
1102 
FLAC__stream_decoder_skip_single_frame(FLAC__StreamDecoder * decoder)1103 FLAC_API FLAC__bool FLAC__stream_decoder_skip_single_frame(FLAC__StreamDecoder *decoder)
1104 {
1105 	FLAC__bool got_a_frame;
1106 	FLAC__ASSERT(0 != decoder);
1107 	FLAC__ASSERT(0 != decoder->protected_);
1108 
1109 	while(1) {
1110 		switch(decoder->protected_->state) {
1111 			case FLAC__STREAM_DECODER_SEARCH_FOR_METADATA:
1112 			case FLAC__STREAM_DECODER_READ_METADATA:
1113 				return false; /* above function sets the status for us */
1114 			case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
1115 				if(!frame_sync_(decoder))
1116 					return true; /* above function sets the status for us */
1117 				break;
1118 			case FLAC__STREAM_DECODER_READ_FRAME:
1119 				if(!read_frame_(decoder, &got_a_frame, /*do_full_decode=*/false))
1120 					return false; /* above function sets the status for us */
1121 				if(got_a_frame)
1122 					return true; /* above function sets the status for us */
1123 				break;
1124 			case FLAC__STREAM_DECODER_END_OF_STREAM:
1125 			case FLAC__STREAM_DECODER_ABORTED:
1126 				return true;
1127 			default:
1128 				FLAC__ASSERT(0);
1129 				return false;
1130 		}
1131 	}
1132 }
1133 
FLAC__stream_decoder_seek_absolute(FLAC__StreamDecoder * decoder,FLAC__uint64 sample)1134 FLAC_API FLAC__bool FLAC__stream_decoder_seek_absolute(FLAC__StreamDecoder *decoder, FLAC__uint64 sample)
1135 {
1136 	FLAC__uint64 length;
1137 
1138 	FLAC__ASSERT(0 != decoder);
1139 
1140 	if(
1141 		decoder->protected_->state != FLAC__STREAM_DECODER_SEARCH_FOR_METADATA &&
1142 		decoder->protected_->state != FLAC__STREAM_DECODER_READ_METADATA &&
1143 		decoder->protected_->state != FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC &&
1144 		decoder->protected_->state != FLAC__STREAM_DECODER_READ_FRAME &&
1145 		decoder->protected_->state != FLAC__STREAM_DECODER_END_OF_STREAM
1146 	)
1147 		return false;
1148 
1149 	if(0 == decoder->private_->seek_callback)
1150 		return false;
1151 
1152 	FLAC__ASSERT(decoder->private_->seek_callback);
1153 	FLAC__ASSERT(decoder->private_->tell_callback);
1154 	FLAC__ASSERT(decoder->private_->length_callback);
1155 	FLAC__ASSERT(decoder->private_->eof_callback);
1156 
1157 	if(FLAC__stream_decoder_get_total_samples(decoder) > 0 && sample >= FLAC__stream_decoder_get_total_samples(decoder))
1158 		return false;
1159 
1160 	decoder->private_->is_seeking = true;
1161 
1162 	/* turn off md5 checking if a seek is attempted */
1163 	decoder->private_->do_md5_checking = false;
1164 
1165 	/* get the file length (currently our algorithm needs to know the length so it's also an error to get FLAC__STREAM_DECODER_LENGTH_STATUS_UNSUPPORTED) */
1166 	if(decoder->private_->length_callback(decoder, &length, decoder->private_->client_data) != FLAC__STREAM_DECODER_LENGTH_STATUS_OK) {
1167 		decoder->private_->is_seeking = false;
1168 		return false;
1169 	}
1170 
1171 	/* if we haven't finished processing the metadata yet, do that so we have the STREAMINFO, SEEK_TABLE, and first_frame_offset */
1172 	if(
1173 		decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_METADATA ||
1174 		decoder->protected_->state == FLAC__STREAM_DECODER_READ_METADATA
1175 	) {
1176 		if(!FLAC__stream_decoder_process_until_end_of_metadata(decoder)) {
1177 			/* above call sets the state for us */
1178 			decoder->private_->is_seeking = false;
1179 			return false;
1180 		}
1181 		/* check this again in case we didn't know total_samples the first time */
1182 		if(FLAC__stream_decoder_get_total_samples(decoder) > 0 && sample >= FLAC__stream_decoder_get_total_samples(decoder)) {
1183 			decoder->private_->is_seeking = false;
1184 			return false;
1185 		}
1186 	}
1187 
1188 	{
1189 		const FLAC__bool ok =
1190 #if FLAC__HAS_OGG
1191 			decoder->private_->is_ogg?
1192 			seek_to_absolute_sample_ogg_(decoder, length, sample) :
1193 #endif
1194 			seek_to_absolute_sample_(decoder, length, sample)
1195 		;
1196 		decoder->private_->is_seeking = false;
1197 		return ok;
1198 	}
1199 }
1200 
1201 /***********************************************************************
1202  *
1203  * Protected class methods
1204  *
1205  ***********************************************************************/
1206 
FLAC__stream_decoder_get_input_bytes_unconsumed(const FLAC__StreamDecoder * decoder)1207 unsigned FLAC__stream_decoder_get_input_bytes_unconsumed(const FLAC__StreamDecoder *decoder)
1208 {
1209 	FLAC__ASSERT(0 != decoder);
1210 	FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1211 	FLAC__ASSERT(!(FLAC__bitreader_get_input_bits_unconsumed(decoder->private_->input) & 7));
1212 	return FLAC__bitreader_get_input_bits_unconsumed(decoder->private_->input) / 8;
1213 }
1214 
1215 /***********************************************************************
1216  *
1217  * Private class methods
1218  *
1219  ***********************************************************************/
1220 
set_defaults_(FLAC__StreamDecoder * decoder)1221 void set_defaults_(FLAC__StreamDecoder *decoder)
1222 {
1223 	decoder->private_->is_ogg = false;
1224 	decoder->private_->read_callback = 0;
1225 	decoder->private_->seek_callback = 0;
1226 	decoder->private_->tell_callback = 0;
1227 	decoder->private_->length_callback = 0;
1228 	decoder->private_->eof_callback = 0;
1229 	decoder->private_->write_callback = 0;
1230 	decoder->private_->metadata_callback = 0;
1231 	decoder->private_->error_callback = 0;
1232 	decoder->private_->client_data = 0;
1233 
1234 	memset(decoder->private_->metadata_filter, 0, sizeof(decoder->private_->metadata_filter));
1235 	decoder->private_->metadata_filter[FLAC__METADATA_TYPE_STREAMINFO] = true;
1236 	decoder->private_->metadata_filter_ids_count = 0;
1237 
1238 	decoder->protected_->md5_checking = false;
1239 
1240 #if FLAC__HAS_OGG
1241 	FLAC__ogg_decoder_aspect_set_defaults(&decoder->protected_->ogg_decoder_aspect);
1242 #endif
1243 }
1244 
1245 /*
1246  * This will forcibly set stdin to binary mode (for OSes that require it)
1247  */
get_binary_stdin_(void)1248 FILE *get_binary_stdin_(void)
1249 {
1250 	/* if something breaks here it is probably due to the presence or
1251 	 * absence of an underscore before the identifiers 'setmode',
1252 	 * 'fileno', and/or 'O_BINARY'; check your system header files.
1253 	 */
1254 #if defined _MSC_VER || defined __MINGW32__
1255 	_setmode(_fileno(stdin), _O_BINARY);
1256 #elif defined __CYGWIN__
1257 	/* almost certainly not needed for any modern Cygwin, but let's be safe... */
1258 	setmode(_fileno(stdin), _O_BINARY);
1259 #elif defined __EMX__
1260 	setmode(fileno(stdin), O_BINARY);
1261 #endif
1262 
1263 	return stdin;
1264 }
1265 
allocate_output_(FLAC__StreamDecoder * decoder,unsigned size,unsigned channels)1266 FLAC__bool allocate_output_(FLAC__StreamDecoder *decoder, unsigned size, unsigned channels)
1267 {
1268 	unsigned i;
1269 	FLAC__int32 *tmp;
1270 
1271 	if(size <= decoder->private_->output_capacity && channels <= decoder->private_->output_channels)
1272 		return true;
1273 
1274 	/* simply using realloc() is not practical because the number of channels may change mid-stream */
1275 
1276 	for(i = 0; i < FLAC__MAX_CHANNELS; i++) {
1277 		if(0 != decoder->private_->output[i]) {
1278 			free(decoder->private_->output[i]-4);
1279 			decoder->private_->output[i] = 0;
1280 		}
1281 		if(0 != decoder->private_->residual_unaligned[i]) {
1282 			free(decoder->private_->residual_unaligned[i]);
1283 			decoder->private_->residual_unaligned[i] = decoder->private_->residual[i] = 0;
1284 		}
1285 	}
1286 
1287 	for(i = 0; i < channels; i++) {
1288 		/* WATCHOUT:
1289 		 * FLAC__lpc_restore_signal_asm_ia32_mmx() requires that the
1290 		 * output arrays have a buffer of up to 3 zeroes in front
1291 		 * (at negative indices) for alignment purposes; we use 4
1292 		 * to keep the data well-aligned.
1293 		 */
1294 		tmp = safe_malloc_muladd2_(sizeof(FLAC__int32), /*times (*/size, /*+*/4/*)*/);
1295 		if(tmp == 0) {
1296 			decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1297 			return false;
1298 		}
1299 		memset(tmp, 0, sizeof(FLAC__int32)*4);
1300 		decoder->private_->output[i] = tmp + 4;
1301 
1302 		if(!FLAC__memory_alloc_aligned_int32_array(size, &decoder->private_->residual_unaligned[i], &decoder->private_->residual[i])) {
1303 			decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1304 			return false;
1305 		}
1306 	}
1307 
1308 	decoder->private_->output_capacity = size;
1309 	decoder->private_->output_channels = channels;
1310 
1311 	return true;
1312 }
1313 
has_id_filtered_(FLAC__StreamDecoder * decoder,FLAC__byte * id)1314 FLAC__bool has_id_filtered_(FLAC__StreamDecoder *decoder, FLAC__byte *id)
1315 {
1316 	size_t i;
1317 
1318 	FLAC__ASSERT(0 != decoder);
1319 	FLAC__ASSERT(0 != decoder->private_);
1320 
1321 	for(i = 0; i < decoder->private_->metadata_filter_ids_count; i++)
1322 		if(0 == memcmp(decoder->private_->metadata_filter_ids + i * (FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8), id, (FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8)))
1323 			return true;
1324 
1325 	return false;
1326 }
1327 
find_metadata_(FLAC__StreamDecoder * decoder)1328 FLAC__bool find_metadata_(FLAC__StreamDecoder *decoder)
1329 {
1330 	FLAC__uint32 x;
1331 	unsigned i, id;
1332 	FLAC__bool first = true;
1333 
1334 	FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1335 
1336 	for(i = id = 0; i < 4; ) {
1337 		if(decoder->private_->cached) {
1338 			x = (FLAC__uint32)decoder->private_->lookahead;
1339 			decoder->private_->cached = false;
1340 		}
1341 		else {
1342 			if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
1343 				return false; /* read_callback_ sets the state for us */
1344 		}
1345 		if(x == FLAC__STREAM_SYNC_STRING[i]) {
1346 			first = true;
1347 			i++;
1348 			id = 0;
1349 			continue;
1350 		}
1351 
1352 		if(id >= 3)
1353 			return false;
1354 
1355 		if(x == ID3V2_TAG_[id]) {
1356 			id++;
1357 			i = 0;
1358 			if(id == 3) {
1359 				if(!skip_id3v2_tag_(decoder))
1360 					return false; /* skip_id3v2_tag_ sets the state for us */
1361 			}
1362 			continue;
1363 		}
1364 		id = 0;
1365 		if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
1366 			decoder->private_->header_warmup[0] = (FLAC__byte)x;
1367 			if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
1368 				return false; /* read_callback_ sets the state for us */
1369 
1370 			/* we have to check if we just read two 0xff's in a row; the second may actually be the beginning of the sync code */
1371 			/* else we have to check if the second byte is the end of a sync code */
1372 			if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
1373 				decoder->private_->lookahead = (FLAC__byte)x;
1374 				decoder->private_->cached = true;
1375 			}
1376 			else if(x >> 1 == 0x7c) { /* MAGIC NUMBER for the last 6 sync bits and reserved 7th bit */
1377 				decoder->private_->header_warmup[1] = (FLAC__byte)x;
1378 				decoder->protected_->state = FLAC__STREAM_DECODER_READ_FRAME;
1379 				return true;
1380 			}
1381 		}
1382 		i = 0;
1383 		if(first) {
1384 			send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
1385 			first = false;
1386 		}
1387 	}
1388 
1389 	decoder->protected_->state = FLAC__STREAM_DECODER_READ_METADATA;
1390 	return true;
1391 }
1392 
read_metadata_(FLAC__StreamDecoder * decoder)1393 FLAC__bool read_metadata_(FLAC__StreamDecoder *decoder)
1394 {
1395 	FLAC__bool is_last;
1396 	FLAC__uint32 i, x, type, length;
1397 
1398 	FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1399 
1400 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_IS_LAST_LEN))
1401 		return false; /* read_callback_ sets the state for us */
1402 	is_last = x? true : false;
1403 
1404 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &type, FLAC__STREAM_METADATA_TYPE_LEN))
1405 		return false; /* read_callback_ sets the state for us */
1406 
1407 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &length, FLAC__STREAM_METADATA_LENGTH_LEN))
1408 		return false; /* read_callback_ sets the state for us */
1409 
1410 	if(type == FLAC__METADATA_TYPE_STREAMINFO) {
1411 		if(!read_metadata_streaminfo_(decoder, is_last, length))
1412 			return false;
1413 
1414 		decoder->private_->has_stream_info = true;
1415 		if(0 == memcmp(decoder->private_->stream_info.data.stream_info.md5sum, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0", 16))
1416 			decoder->private_->do_md5_checking = false;
1417 		if(!decoder->private_->is_seeking && decoder->private_->metadata_filter[FLAC__METADATA_TYPE_STREAMINFO] && decoder->private_->metadata_callback)
1418 			decoder->private_->metadata_callback(decoder, &decoder->private_->stream_info, decoder->private_->client_data);
1419 	}
1420 	else if(type == FLAC__METADATA_TYPE_SEEKTABLE) {
1421 		/* just in case we already have a seek table, and reading the next one fails: */
1422 		decoder->private_->has_seek_table = false;
1423 
1424 		if(!read_metadata_seektable_(decoder, is_last, length))
1425 			return false;
1426 
1427 		decoder->private_->has_seek_table = true;
1428 		if(!decoder->private_->is_seeking && decoder->private_->metadata_filter[FLAC__METADATA_TYPE_SEEKTABLE] && decoder->private_->metadata_callback)
1429 			decoder->private_->metadata_callback(decoder, &decoder->private_->seek_table, decoder->private_->client_data);
1430 	}
1431 	else {
1432 		FLAC__bool skip_it = !decoder->private_->metadata_filter[type];
1433 		unsigned real_length = length;
1434 		FLAC__StreamMetadata block;
1435 
1436 		memset(&block, 0, sizeof(block));
1437 		block.is_last = is_last;
1438 		block.type = (FLAC__MetadataType)type;
1439 		block.length = length;
1440 
1441 		if(type == FLAC__METADATA_TYPE_APPLICATION) {
1442 			if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, block.data.application.id, FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8))
1443 				return false; /* read_callback_ sets the state for us */
1444 
1445 			if(real_length < FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8) { /* underflow check */
1446 				decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;/*@@@@@@ maybe wrong error? need to resync?*/
1447 				return false;
1448 			}
1449 
1450 			real_length -= FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8;
1451 
1452 			if(decoder->private_->metadata_filter_ids_count > 0 && has_id_filtered_(decoder, block.data.application.id))
1453 				skip_it = !skip_it;
1454 		}
1455 
1456 		if(skip_it) {
1457 			if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, real_length))
1458 				return false; /* read_callback_ sets the state for us */
1459 		}
1460 		else {
1461 			FLAC__bool ok = true;
1462 			switch(type) {
1463 				case FLAC__METADATA_TYPE_PADDING:
1464 					/* skip the padding bytes */
1465 					if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, real_length))
1466 						ok = false; /* read_callback_ sets the state for us */
1467 					break;
1468 				case FLAC__METADATA_TYPE_APPLICATION:
1469 					/* remember, we read the ID already */
1470 					if(real_length > 0) {
1471 						if(0 == (block.data.application.data = malloc(real_length))) {
1472 							decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1473 							ok = false;
1474 						}
1475 						else if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, block.data.application.data, real_length))
1476 							ok = false; /* read_callback_ sets the state for us */
1477 					}
1478 					else
1479 						block.data.application.data = 0;
1480 					break;
1481 				case FLAC__METADATA_TYPE_VORBIS_COMMENT:
1482 					if(!read_metadata_vorbiscomment_(decoder, &block.data.vorbis_comment, real_length))
1483 						ok = false;
1484 					break;
1485 				case FLAC__METADATA_TYPE_CUESHEET:
1486 					if(!read_metadata_cuesheet_(decoder, &block.data.cue_sheet))
1487 						ok = false;
1488 					break;
1489 				case FLAC__METADATA_TYPE_PICTURE:
1490 					if(!read_metadata_picture_(decoder, &block.data.picture))
1491 						ok = false;
1492 					break;
1493 				case FLAC__METADATA_TYPE_STREAMINFO:
1494 				case FLAC__METADATA_TYPE_SEEKTABLE:
1495 					FLAC__ASSERT(0);
1496 					break;
1497 				default:
1498 					if(real_length > 0) {
1499 						if(0 == (block.data.unknown.data = malloc(real_length))) {
1500 							decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1501 							ok = false;
1502 						}
1503 						else if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, block.data.unknown.data, real_length))
1504 							ok = false; /* read_callback_ sets the state for us */
1505 					}
1506 					else
1507 						block.data.unknown.data = 0;
1508 					break;
1509 			}
1510 			if(ok && !decoder->private_->is_seeking && decoder->private_->metadata_callback)
1511 				decoder->private_->metadata_callback(decoder, &block, decoder->private_->client_data);
1512 
1513 			/* now we have to free any malloc()ed data in the block */
1514 			switch(type) {
1515 				case FLAC__METADATA_TYPE_PADDING:
1516 					break;
1517 				case FLAC__METADATA_TYPE_APPLICATION:
1518 					if(0 != block.data.application.data)
1519 						free(block.data.application.data);
1520 					break;
1521 				case FLAC__METADATA_TYPE_VORBIS_COMMENT:
1522 					if(0 != block.data.vorbis_comment.vendor_string.entry)
1523 						free(block.data.vorbis_comment.vendor_string.entry);
1524 					if(block.data.vorbis_comment.num_comments > 0)
1525 						for(i = 0; i < block.data.vorbis_comment.num_comments; i++)
1526 							if(0 != block.data.vorbis_comment.comments[i].entry)
1527 								free(block.data.vorbis_comment.comments[i].entry);
1528 					if(0 != block.data.vorbis_comment.comments)
1529 						free(block.data.vorbis_comment.comments);
1530 					break;
1531 				case FLAC__METADATA_TYPE_CUESHEET:
1532 					if(block.data.cue_sheet.num_tracks > 0)
1533 						for(i = 0; i < block.data.cue_sheet.num_tracks; i++)
1534 							if(0 != block.data.cue_sheet.tracks[i].indices)
1535 								free(block.data.cue_sheet.tracks[i].indices);
1536 					if(0 != block.data.cue_sheet.tracks)
1537 						free(block.data.cue_sheet.tracks);
1538 					break;
1539 				case FLAC__METADATA_TYPE_PICTURE:
1540 					if(0 != block.data.picture.mime_type)
1541 						free(block.data.picture.mime_type);
1542 					if(0 != block.data.picture.description)
1543 						free(block.data.picture.description);
1544 					if(0 != block.data.picture.data)
1545 						free(block.data.picture.data);
1546 					break;
1547 				case FLAC__METADATA_TYPE_STREAMINFO:
1548 				case FLAC__METADATA_TYPE_SEEKTABLE:
1549 					FLAC__ASSERT(0);
1550 				default:
1551 					if(0 != block.data.unknown.data)
1552 						free(block.data.unknown.data);
1553 					break;
1554 			}
1555 
1556 			if(!ok) /* anything that unsets "ok" should also make sure decoder->protected_->state is updated */
1557 				return false;
1558 		}
1559 	}
1560 
1561 	if(is_last) {
1562 		/* if this fails, it's OK, it's just a hint for the seek routine */
1563 		if(!FLAC__stream_decoder_get_decode_position(decoder, &decoder->private_->first_frame_offset))
1564 			decoder->private_->first_frame_offset = 0;
1565 		decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
1566 	}
1567 
1568 	return true;
1569 }
1570 
read_metadata_streaminfo_(FLAC__StreamDecoder * decoder,FLAC__bool is_last,unsigned length)1571 FLAC__bool read_metadata_streaminfo_(FLAC__StreamDecoder *decoder, FLAC__bool is_last, unsigned length)
1572 {
1573 	FLAC__uint32 x;
1574 	unsigned bits, used_bits = 0;
1575 
1576 	FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1577 
1578 	decoder->private_->stream_info.type = FLAC__METADATA_TYPE_STREAMINFO;
1579 	decoder->private_->stream_info.is_last = is_last;
1580 	decoder->private_->stream_info.length = length;
1581 
1582 	bits = FLAC__STREAM_METADATA_STREAMINFO_MIN_BLOCK_SIZE_LEN;
1583 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, bits))
1584 		return false; /* read_callback_ sets the state for us */
1585 	decoder->private_->stream_info.data.stream_info.min_blocksize = x;
1586 	used_bits += bits;
1587 
1588 	bits = FLAC__STREAM_METADATA_STREAMINFO_MAX_BLOCK_SIZE_LEN;
1589 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_MAX_BLOCK_SIZE_LEN))
1590 		return false; /* read_callback_ sets the state for us */
1591 	decoder->private_->stream_info.data.stream_info.max_blocksize = x;
1592 	used_bits += bits;
1593 
1594 	bits = FLAC__STREAM_METADATA_STREAMINFO_MIN_FRAME_SIZE_LEN;
1595 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_MIN_FRAME_SIZE_LEN))
1596 		return false; /* read_callback_ sets the state for us */
1597 	decoder->private_->stream_info.data.stream_info.min_framesize = x;
1598 	used_bits += bits;
1599 
1600 	bits = FLAC__STREAM_METADATA_STREAMINFO_MAX_FRAME_SIZE_LEN;
1601 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_MAX_FRAME_SIZE_LEN))
1602 		return false; /* read_callback_ sets the state for us */
1603 	decoder->private_->stream_info.data.stream_info.max_framesize = x;
1604 	used_bits += bits;
1605 
1606 	bits = FLAC__STREAM_METADATA_STREAMINFO_SAMPLE_RATE_LEN;
1607 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_SAMPLE_RATE_LEN))
1608 		return false; /* read_callback_ sets the state for us */
1609 	decoder->private_->stream_info.data.stream_info.sample_rate = x;
1610 	used_bits += bits;
1611 
1612 	bits = FLAC__STREAM_METADATA_STREAMINFO_CHANNELS_LEN;
1613 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_CHANNELS_LEN))
1614 		return false; /* read_callback_ sets the state for us */
1615 	decoder->private_->stream_info.data.stream_info.channels = x+1;
1616 	used_bits += bits;
1617 
1618 	bits = FLAC__STREAM_METADATA_STREAMINFO_BITS_PER_SAMPLE_LEN;
1619 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_BITS_PER_SAMPLE_LEN))
1620 		return false; /* read_callback_ sets the state for us */
1621 	decoder->private_->stream_info.data.stream_info.bits_per_sample = x+1;
1622 	used_bits += bits;
1623 
1624 	bits = FLAC__STREAM_METADATA_STREAMINFO_TOTAL_SAMPLES_LEN;
1625 	if(!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &decoder->private_->stream_info.data.stream_info.total_samples, FLAC__STREAM_METADATA_STREAMINFO_TOTAL_SAMPLES_LEN))
1626 		return false; /* read_callback_ sets the state for us */
1627 	used_bits += bits;
1628 
1629 	if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, decoder->private_->stream_info.data.stream_info.md5sum, 16))
1630 		return false; /* read_callback_ sets the state for us */
1631 	used_bits += 16*8;
1632 
1633 	/* skip the rest of the block */
1634 	FLAC__ASSERT(used_bits % 8 == 0);
1635 	length -= (used_bits / 8);
1636 	if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, length))
1637 		return false; /* read_callback_ sets the state for us */
1638 
1639 	return true;
1640 }
1641 
read_metadata_seektable_(FLAC__StreamDecoder * decoder,FLAC__bool is_last,unsigned length)1642 FLAC__bool read_metadata_seektable_(FLAC__StreamDecoder *decoder, FLAC__bool is_last, unsigned length)
1643 {
1644 	FLAC__uint32 i, x;
1645 	FLAC__uint64 xx;
1646 
1647 	FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1648 
1649 	decoder->private_->seek_table.type = FLAC__METADATA_TYPE_SEEKTABLE;
1650 	decoder->private_->seek_table.is_last = is_last;
1651 	decoder->private_->seek_table.length = length;
1652 
1653 	decoder->private_->seek_table.data.seek_table.num_points = length / FLAC__STREAM_METADATA_SEEKPOINT_LENGTH;
1654 
1655 	/* use realloc since we may pass through here several times (e.g. after seeking) */
1656 	if(0 == (decoder->private_->seek_table.data.seek_table.points = safe_realloc_mul_2op_(decoder->private_->seek_table.data.seek_table.points, decoder->private_->seek_table.data.seek_table.num_points, /*times*/sizeof(FLAC__StreamMetadata_SeekPoint)))) {
1657 		decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1658 		return false;
1659 	}
1660 	for(i = 0; i < decoder->private_->seek_table.data.seek_table.num_points; i++) {
1661 		if(!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &xx, FLAC__STREAM_METADATA_SEEKPOINT_SAMPLE_NUMBER_LEN))
1662 			return false; /* read_callback_ sets the state for us */
1663 		decoder->private_->seek_table.data.seek_table.points[i].sample_number = xx;
1664 
1665 		if(!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &xx, FLAC__STREAM_METADATA_SEEKPOINT_STREAM_OFFSET_LEN))
1666 			return false; /* read_callback_ sets the state for us */
1667 		decoder->private_->seek_table.data.seek_table.points[i].stream_offset = xx;
1668 
1669 		if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_SEEKPOINT_FRAME_SAMPLES_LEN))
1670 			return false; /* read_callback_ sets the state for us */
1671 		decoder->private_->seek_table.data.seek_table.points[i].frame_samples = x;
1672 	}
1673 	length -= (decoder->private_->seek_table.data.seek_table.num_points * FLAC__STREAM_METADATA_SEEKPOINT_LENGTH);
1674 	/* if there is a partial point left, skip over it */
1675 	if(length > 0) {
1676 		/*@@@ do a send_error_to_client_() here?  there's an argument for either way */
1677 		if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, length))
1678 			return false; /* read_callback_ sets the state for us */
1679 	}
1680 
1681 	return true;
1682 }
1683 
read_metadata_vorbiscomment_(FLAC__StreamDecoder * decoder,FLAC__StreamMetadata_VorbisComment * obj,unsigned length)1684 FLAC__bool read_metadata_vorbiscomment_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_VorbisComment *obj, unsigned length)
1685 {
1686 	FLAC__uint32 i;
1687 
1688 	FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1689 
1690 	/* read vendor string */
1691 	if (length >= 8) {
1692 		length -= 8; /* vendor string length + num comments entries alone take 8 bytes */
1693 		FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN == 32);
1694 		if (!FLAC__bitreader_read_uint32_little_endian(decoder->private_->input, &obj->vendor_string.length))
1695 			return false; /* read_callback_ sets the state for us */
1696 		if (obj->vendor_string.length > 0) {
1697 			if (length < obj->vendor_string.length) {
1698 				obj->vendor_string.length = 0;
1699 				obj->vendor_string.entry = 0;
1700 				goto skip;
1701 			}
1702 			else
1703 				length -= obj->vendor_string.length;
1704 			if (0 == (obj->vendor_string.entry = safe_malloc_add_2op_(obj->vendor_string.length, /*+*/1))) {
1705 				decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1706 				return false;
1707 			}
1708 			if (!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, obj->vendor_string.entry, obj->vendor_string.length))
1709 				return false; /* read_callback_ sets the state for us */
1710 			obj->vendor_string.entry[obj->vendor_string.length] = '\0';
1711 		}
1712 		else
1713 			obj->vendor_string.entry = 0;
1714 
1715 		/* read num comments */
1716 		FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_NUM_COMMENTS_LEN == 32);
1717 		if (!FLAC__bitreader_read_uint32_little_endian(decoder->private_->input, &obj->num_comments))
1718 			return false; /* read_callback_ sets the state for us */
1719 
1720 		/* read comments */
1721 		if (obj->num_comments > 100000) {
1722 			/* Possibly malicious file. */
1723 			obj->num_comments = 0;
1724 			return false;
1725 		}
1726 		if (obj->num_comments > 0) {
1727 			if (0 == (obj->comments = safe_malloc_mul_2op_p(obj->num_comments, /*times*/sizeof(FLAC__StreamMetadata_VorbisComment_Entry)))) {
1728 				obj->num_comments = 0;
1729 				decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1730 				return false;
1731 			}
1732 			for (i = 0; i < obj->num_comments; i++) {
1733 				/* Initialize here just to make sure. */
1734 				obj->comments[i].length = 0;
1735 				obj->comments[i].entry = 0;
1736 
1737 				FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN == 32);
1738 				if (length < 4) {
1739 					obj->num_comments = i;
1740 					goto skip;
1741 				}
1742 				else
1743 					length -= 4;
1744 				if (!FLAC__bitreader_read_uint32_little_endian(decoder->private_->input, &obj->comments[i].length)) {
1745 					obj->num_comments = i;
1746 					return false; /* read_callback_ sets the state for us */
1747 				}
1748 				if (obj->comments[i].length > 0) {
1749 					if (length < obj->comments[i].length) {
1750 						obj->num_comments = i;
1751 						goto skip;
1752 					}
1753 					else
1754 						length -= obj->comments[i].length;
1755 					if (0 == (obj->comments[i].entry = safe_malloc_add_2op_(obj->comments[i].length, /*+*/1))) {
1756 						decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1757 						obj->num_comments = i;
1758 						return false;
1759 					}
1760 					memset (obj->comments[i].entry, 0, obj->comments[i].length) ;
1761 					if (!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, obj->comments[i].entry, obj->comments[i].length)) {
1762 						obj->num_comments = i;
1763 						goto skip;
1764 					}
1765 					obj->comments[i].entry[obj->comments[i].length] = '\0';
1766 				}
1767 				else
1768 					obj->comments[i].entry = 0;
1769 			}
1770 		}
1771 	}
1772 
1773   skip:
1774 	if (length > 0) {
1775 		/* length > 0 can only happen on files with invalid data in comments */
1776 		if(obj->num_comments < 1) {
1777 			free(obj->comments);
1778 			obj->comments = NULL;
1779 		}
1780 		if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, length))
1781 			return false; /* read_callback_ sets the state for us */
1782 	}
1783 
1784 	return true;
1785 }
1786 
read_metadata_cuesheet_(FLAC__StreamDecoder * decoder,FLAC__StreamMetadata_CueSheet * obj)1787 FLAC__bool read_metadata_cuesheet_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_CueSheet *obj)
1788 {
1789 	FLAC__uint32 i, j, x;
1790 
1791 	FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1792 
1793 	memset(obj, 0, sizeof(FLAC__StreamMetadata_CueSheet));
1794 
1795 	FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_MEDIA_CATALOG_NUMBER_LEN % 8 == 0);
1796 	if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, (FLAC__byte*)obj->media_catalog_number, FLAC__STREAM_METADATA_CUESHEET_MEDIA_CATALOG_NUMBER_LEN/8))
1797 		return false; /* read_callback_ sets the state for us */
1798 
1799 	if(!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &obj->lead_in, FLAC__STREAM_METADATA_CUESHEET_LEAD_IN_LEN))
1800 		return false; /* read_callback_ sets the state for us */
1801 
1802 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_IS_CD_LEN))
1803 		return false; /* read_callback_ sets the state for us */
1804 	obj->is_cd = x? true : false;
1805 
1806 	if(!FLAC__bitreader_skip_bits_no_crc(decoder->private_->input, FLAC__STREAM_METADATA_CUESHEET_RESERVED_LEN))
1807 		return false; /* read_callback_ sets the state for us */
1808 
1809 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_NUM_TRACKS_LEN))
1810 		return false; /* read_callback_ sets the state for us */
1811 	obj->num_tracks = x;
1812 
1813 	if(obj->num_tracks > 0) {
1814 		if(0 == (obj->tracks = safe_calloc_(obj->num_tracks, sizeof(FLAC__StreamMetadata_CueSheet_Track)))) {
1815 			decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1816 			return false;
1817 		}
1818 		for(i = 0; i < obj->num_tracks; i++) {
1819 			FLAC__StreamMetadata_CueSheet_Track *track = &obj->tracks[i];
1820 			if(!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &track->offset, FLAC__STREAM_METADATA_CUESHEET_TRACK_OFFSET_LEN))
1821 				return false; /* read_callback_ sets the state for us */
1822 
1823 			if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_TRACK_NUMBER_LEN))
1824 				return false; /* read_callback_ sets the state for us */
1825 			track->number = (FLAC__byte)x;
1826 
1827 			FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_TRACK_ISRC_LEN % 8 == 0);
1828 			if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, (FLAC__byte*)track->isrc, FLAC__STREAM_METADATA_CUESHEET_TRACK_ISRC_LEN/8))
1829 				return false; /* read_callback_ sets the state for us */
1830 
1831 			if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_TRACK_TYPE_LEN))
1832 				return false; /* read_callback_ sets the state for us */
1833 			track->type = x;
1834 
1835 			if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_TRACK_PRE_EMPHASIS_LEN))
1836 				return false; /* read_callback_ sets the state for us */
1837 			track->pre_emphasis = x;
1838 
1839 			if(!FLAC__bitreader_skip_bits_no_crc(decoder->private_->input, FLAC__STREAM_METADATA_CUESHEET_TRACK_RESERVED_LEN))
1840 				return false; /* read_callback_ sets the state for us */
1841 
1842 			if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_TRACK_NUM_INDICES_LEN))
1843 				return false; /* read_callback_ sets the state for us */
1844 			track->num_indices = (FLAC__byte)x;
1845 
1846 			if(track->num_indices > 0) {
1847 				if(0 == (track->indices = safe_calloc_(track->num_indices, sizeof(FLAC__StreamMetadata_CueSheet_Index)))) {
1848 					decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1849 					return false;
1850 				}
1851 				for(j = 0; j < track->num_indices; j++) {
1852 					FLAC__StreamMetadata_CueSheet_Index *indx = &track->indices[j];
1853 					if(!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &indx->offset, FLAC__STREAM_METADATA_CUESHEET_INDEX_OFFSET_LEN))
1854 						return false; /* read_callback_ sets the state for us */
1855 
1856 					if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_INDEX_NUMBER_LEN))
1857 						return false; /* read_callback_ sets the state for us */
1858 					indx->number = (FLAC__byte)x;
1859 
1860 					if(!FLAC__bitreader_skip_bits_no_crc(decoder->private_->input, FLAC__STREAM_METADATA_CUESHEET_INDEX_RESERVED_LEN))
1861 						return false; /* read_callback_ sets the state for us */
1862 				}
1863 			}
1864 		}
1865 	}
1866 
1867 	return true;
1868 }
1869 
read_metadata_picture_(FLAC__StreamDecoder * decoder,FLAC__StreamMetadata_Picture * obj)1870 FLAC__bool read_metadata_picture_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_Picture *obj)
1871 {
1872 	FLAC__uint32 x;
1873 
1874 	FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1875 
1876 	/* read type */
1877 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_PICTURE_TYPE_LEN))
1878 		return false; /* read_callback_ sets the state for us */
1879 	obj->type = x;
1880 
1881 	/* read MIME type */
1882 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_PICTURE_MIME_TYPE_LENGTH_LEN))
1883 		return false; /* read_callback_ sets the state for us */
1884 	if(0 == (obj->mime_type = safe_malloc_add_2op_(x, /*+*/1))) {
1885 		decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1886 		return false;
1887 	}
1888 	if(x > 0) {
1889 		if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, (FLAC__byte*)obj->mime_type, x))
1890 			return false; /* read_callback_ sets the state for us */
1891 	}
1892 	obj->mime_type[x] = '\0';
1893 
1894 	/* read description */
1895 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_PICTURE_DESCRIPTION_LENGTH_LEN))
1896 		return false; /* read_callback_ sets the state for us */
1897 	if(0 == (obj->description = safe_malloc_add_2op_(x, /*+*/1))) {
1898 		decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1899 		return false;
1900 	}
1901 	if(x > 0) {
1902 		if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, obj->description, x))
1903 			return false; /* read_callback_ sets the state for us */
1904 	}
1905 	obj->description[x] = '\0';
1906 
1907 	/* read width */
1908 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &obj->width, FLAC__STREAM_METADATA_PICTURE_WIDTH_LEN))
1909 		return false; /* read_callback_ sets the state for us */
1910 
1911 	/* read height */
1912 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &obj->height, FLAC__STREAM_METADATA_PICTURE_HEIGHT_LEN))
1913 		return false; /* read_callback_ sets the state for us */
1914 
1915 	/* read depth */
1916 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &obj->depth, FLAC__STREAM_METADATA_PICTURE_DEPTH_LEN))
1917 		return false; /* read_callback_ sets the state for us */
1918 
1919 	/* read colors */
1920 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &obj->colors, FLAC__STREAM_METADATA_PICTURE_COLORS_LEN))
1921 		return false; /* read_callback_ sets the state for us */
1922 
1923 	/* read data */
1924 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &(obj->data_length), FLAC__STREAM_METADATA_PICTURE_DATA_LENGTH_LEN))
1925 		return false; /* read_callback_ sets the state for us */
1926 	if(0 == (obj->data = safe_malloc_(obj->data_length))) {
1927 		decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1928 		return false;
1929 	}
1930 	if(obj->data_length > 0) {
1931 		if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, obj->data, obj->data_length))
1932 			return false; /* read_callback_ sets the state for us */
1933 	}
1934 
1935 	return true;
1936 }
1937 
skip_id3v2_tag_(FLAC__StreamDecoder * decoder)1938 FLAC__bool skip_id3v2_tag_(FLAC__StreamDecoder *decoder)
1939 {
1940 	FLAC__uint32 x;
1941 	unsigned i, skip;
1942 
1943 	/* skip the version and flags bytes */
1944 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 24))
1945 		return false; /* read_callback_ sets the state for us */
1946 	/* get the size (in bytes) to skip */
1947 	skip = 0;
1948 	for(i = 0; i < 4; i++) {
1949 		if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
1950 			return false; /* read_callback_ sets the state for us */
1951 		skip <<= 7;
1952 		skip |= (x & 0x7f);
1953 	}
1954 	/* skip the rest of the tag */
1955 	if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, skip))
1956 		return false; /* read_callback_ sets the state for us */
1957 	return true;
1958 }
1959 
frame_sync_(FLAC__StreamDecoder * decoder)1960 FLAC__bool frame_sync_(FLAC__StreamDecoder *decoder)
1961 {
1962 	FLAC__uint32 x;
1963 	FLAC__bool first = true;
1964 
1965 	/* If we know the total number of samples in the stream, stop if we've read that many. */
1966 	/* This will stop us, for example, from wasting time trying to sync on an ID3V1 tag. */
1967 	if(FLAC__stream_decoder_get_total_samples(decoder) > 0) {
1968 		if(decoder->private_->samples_decoded >= FLAC__stream_decoder_get_total_samples(decoder)) {
1969 			decoder->protected_->state = FLAC__STREAM_DECODER_END_OF_STREAM;
1970 			return true;
1971 		}
1972 	}
1973 
1974 	/* make sure we're byte aligned */
1975 	if(!FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input)) {
1976 		if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__bitreader_bits_left_for_byte_alignment(decoder->private_->input)))
1977 			return false; /* read_callback_ sets the state for us */
1978 	}
1979 
1980 	while(1) {
1981 		if(decoder->private_->cached) {
1982 			x = (FLAC__uint32)decoder->private_->lookahead;
1983 			decoder->private_->cached = false;
1984 		}
1985 		else {
1986 			if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
1987 				return false; /* read_callback_ sets the state for us */
1988 		}
1989 		if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
1990 			decoder->private_->header_warmup[0] = (FLAC__byte)x;
1991 			if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
1992 				return false; /* read_callback_ sets the state for us */
1993 
1994 			/* we have to check if we just read two 0xff's in a row; the second may actually be the beginning of the sync code */
1995 			/* else we have to check if the second byte is the end of a sync code */
1996 			if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
1997 				decoder->private_->lookahead = (FLAC__byte)x;
1998 				decoder->private_->cached = true;
1999 			}
2000 			else if(x >> 1 == 0x7c) { /* MAGIC NUMBER for the last 6 sync bits and reserved 7th bit */
2001 				decoder->private_->header_warmup[1] = (FLAC__byte)x;
2002 				decoder->protected_->state = FLAC__STREAM_DECODER_READ_FRAME;
2003 				return true;
2004 			}
2005 		}
2006 		if(first) {
2007 			send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
2008 			first = false;
2009 		}
2010 	}
2011 
2012 	return true;
2013 }
2014 
read_frame_(FLAC__StreamDecoder * decoder,FLAC__bool * got_a_frame,FLAC__bool do_full_decode)2015 FLAC__bool read_frame_(FLAC__StreamDecoder *decoder, FLAC__bool *got_a_frame, FLAC__bool do_full_decode)
2016 {
2017 	unsigned channel;
2018 	unsigned i;
2019 	FLAC__int32 mid, side;
2020 	unsigned frame_crc; /* the one we calculate from the input stream */
2021 	FLAC__uint32 x;
2022 
2023 	*got_a_frame = false;
2024 
2025 	/* init the CRC */
2026 	frame_crc = 0;
2027 	frame_crc = FLAC__CRC16_UPDATE(decoder->private_->header_warmup[0], frame_crc);
2028 	frame_crc = FLAC__CRC16_UPDATE(decoder->private_->header_warmup[1], frame_crc);
2029 	FLAC__bitreader_reset_read_crc16(decoder->private_->input, (FLAC__uint16)frame_crc);
2030 
2031 	if(!read_frame_header_(decoder))
2032 		return false;
2033 	if(decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) /* means we didn't sync on a valid header */
2034 		return true;
2035 	if(!allocate_output_(decoder, decoder->private_->frame.header.blocksize, decoder->private_->frame.header.channels))
2036 		return false;
2037 	for(channel = 0; channel < decoder->private_->frame.header.channels; channel++) {
2038 		/*
2039 		 * first figure the correct bits-per-sample of the subframe
2040 		 */
2041 		unsigned bps = decoder->private_->frame.header.bits_per_sample;
2042 		switch(decoder->private_->frame.header.channel_assignment) {
2043 			case FLAC__CHANNEL_ASSIGNMENT_INDEPENDENT:
2044 				/* no adjustment needed */
2045 				break;
2046 			case FLAC__CHANNEL_ASSIGNMENT_LEFT_SIDE:
2047 				FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
2048 				if(channel == 1)
2049 					bps++;
2050 				break;
2051 			case FLAC__CHANNEL_ASSIGNMENT_RIGHT_SIDE:
2052 				FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
2053 				if(channel == 0)
2054 					bps++;
2055 				break;
2056 			case FLAC__CHANNEL_ASSIGNMENT_MID_SIDE:
2057 				FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
2058 				if(channel == 1)
2059 					bps++;
2060 				break;
2061 			default:
2062 				FLAC__ASSERT(0);
2063 		}
2064 		/*
2065 		 * now read it
2066 		 */
2067 		if(!read_subframe_(decoder, channel, bps, do_full_decode))
2068 			return false;
2069 		if(decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) /* means bad sync or got corruption */
2070 			return true;
2071 	}
2072 	if(!read_zero_padding_(decoder))
2073 		return false;
2074 	if(decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) /* means bad sync or got corruption (i.e. "zero bits" were not all zeroes) */
2075 		return true;
2076 
2077 	/*
2078 	 * Read the frame CRC-16 from the footer and check
2079 	 */
2080 	frame_crc = FLAC__bitreader_get_read_crc16(decoder->private_->input);
2081 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__FRAME_FOOTER_CRC_LEN))
2082 		return false; /* read_callback_ sets the state for us */
2083 	if(frame_crc == x) {
2084 		if(do_full_decode) {
2085 			/* Undo any special channel coding */
2086 			switch(decoder->private_->frame.header.channel_assignment) {
2087 				case FLAC__CHANNEL_ASSIGNMENT_INDEPENDENT:
2088 					/* do nothing */
2089 					break;
2090 				case FLAC__CHANNEL_ASSIGNMENT_LEFT_SIDE:
2091 					FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
2092 					for(i = 0; i < decoder->private_->frame.header.blocksize; i++)
2093 						decoder->private_->output[1][i] = decoder->private_->output[0][i] - decoder->private_->output[1][i];
2094 					break;
2095 				case FLAC__CHANNEL_ASSIGNMENT_RIGHT_SIDE:
2096 					FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
2097 					for(i = 0; i < decoder->private_->frame.header.blocksize; i++)
2098 						decoder->private_->output[0][i] += decoder->private_->output[1][i];
2099 					break;
2100 				case FLAC__CHANNEL_ASSIGNMENT_MID_SIDE:
2101 					FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
2102 					for(i = 0; i < decoder->private_->frame.header.blocksize; i++) {
2103 #if 1
2104 						mid = decoder->private_->output[0][i];
2105 						side = decoder->private_->output[1][i];
2106 						mid = ((uint32_t) mid) << 1;
2107 						mid |= (side & 1); /* i.e. if 'side' is odd... */
2108 						decoder->private_->output[0][i] = (mid + side) >> 1;
2109 						decoder->private_->output[1][i] = (mid - side) >> 1;
2110 #else
2111 						/* OPT: without 'side' temp variable */
2112 						mid = (decoder->private_->output[0][i] << 1) | (decoder->private_->output[1][i] & 1); /* i.e. if 'side' is odd... */
2113 						decoder->private_->output[0][i] = (mid + decoder->private_->output[1][i]) >> 1;
2114 						decoder->private_->output[1][i] = (mid - decoder->private_->output[1][i]) >> 1;
2115 #endif
2116 					}
2117 					break;
2118 				default:
2119 					FLAC__ASSERT(0);
2120 					break;
2121 			}
2122 		}
2123 	}
2124 	else {
2125 		/* Bad frame, emit error and zero the output signal */
2126 		send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_FRAME_CRC_MISMATCH);
2127 		if(do_full_decode) {
2128 			for(channel = 0; channel < decoder->private_->frame.header.channels; channel++) {
2129 				memset(decoder->private_->output[channel], 0, sizeof(FLAC__int32) * decoder->private_->frame.header.blocksize);
2130 			}
2131 		}
2132 	}
2133 
2134 	*got_a_frame = true;
2135 
2136 	/* we wait to update fixed_block_size until here, when we're sure we've got a proper frame and hence a correct blocksize */
2137 	if(decoder->private_->next_fixed_block_size)
2138 		decoder->private_->fixed_block_size = decoder->private_->next_fixed_block_size;
2139 
2140 	/* put the latest values into the public section of the decoder instance */
2141 	decoder->protected_->channels = decoder->private_->frame.header.channels;
2142 	decoder->protected_->channel_assignment = decoder->private_->frame.header.channel_assignment;
2143 	decoder->protected_->bits_per_sample = decoder->private_->frame.header.bits_per_sample;
2144 	decoder->protected_->sample_rate = decoder->private_->frame.header.sample_rate;
2145 	decoder->protected_->blocksize = decoder->private_->frame.header.blocksize;
2146 
2147 	FLAC__ASSERT(decoder->private_->frame.header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER);
2148 	decoder->private_->samples_decoded = decoder->private_->frame.header.number.sample_number + decoder->private_->frame.header.blocksize;
2149 
2150 	/* write it */
2151 	if(do_full_decode) {
2152 		if(write_audio_frame_to_client_(decoder, &decoder->private_->frame, (const FLAC__int32 * const *)decoder->private_->output) != FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE) {
2153 			decoder->protected_->state = FLAC__STREAM_DECODER_ABORTED;
2154 			return false;
2155 		}
2156 	}
2157 
2158 	decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2159 	return true;
2160 }
2161 
read_frame_header_(FLAC__StreamDecoder * decoder)2162 FLAC__bool read_frame_header_(FLAC__StreamDecoder *decoder)
2163 {
2164 	FLAC__uint32 x;
2165 	FLAC__uint64 xx;
2166 	unsigned i, blocksize_hint = 0, sample_rate_hint = 0;
2167 	FLAC__byte crc8, raw_header[16]; /* MAGIC NUMBER based on the maximum frame header size, including CRC */
2168 	unsigned raw_header_len;
2169 	FLAC__bool is_unparseable = false;
2170 
2171 	FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
2172 
2173 	/* init the raw header with the saved bits from synchronization */
2174 	raw_header[0] = decoder->private_->header_warmup[0];
2175 	raw_header[1] = decoder->private_->header_warmup[1];
2176 	raw_header_len = 2;
2177 
2178 	/* check to make sure that reserved bit is 0 */
2179 	if(raw_header[1] & 0x02) /* MAGIC NUMBER */
2180 		is_unparseable = true;
2181 
2182 	/*
2183 	 * Note that along the way as we read the header, we look for a sync
2184 	 * code inside.  If we find one it would indicate that our original
2185 	 * sync was bad since there cannot be a sync code in a valid header.
2186 	 *
2187 	 * Three kinds of things can go wrong when reading the frame header:
2188 	 *  1) We may have sync'ed incorrectly and not landed on a frame header.
2189 	 *     If we don't find a sync code, it can end up looking like we read
2190 	 *     a valid but unparseable header, until getting to the frame header
2191 	 *     CRC.  Even then we could get a false positive on the CRC.
2192 	 *  2) We may have sync'ed correctly but on an unparseable frame (from a
2193 	 *     future encoder).
2194 	 *  3) We may be on a damaged frame which appears valid but unparseable.
2195 	 *
2196 	 * For all these reasons, we try and read a complete frame header as
2197 	 * long as it seems valid, even if unparseable, up until the frame
2198 	 * header CRC.
2199 	 */
2200 
2201 	/*
2202 	 * read in the raw header as bytes so we can CRC it, and parse it on the way
2203 	 */
2204 	for(i = 0; i < 2; i++) {
2205 		if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
2206 			return false; /* read_callback_ sets the state for us */
2207 		if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
2208 			/* if we get here it means our original sync was erroneous since the sync code cannot appear in the header */
2209 			decoder->private_->lookahead = (FLAC__byte)x;
2210 			decoder->private_->cached = true;
2211 			send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
2212 			decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2213 			return true;
2214 		}
2215 		raw_header[raw_header_len++] = (FLAC__byte)x;
2216 	}
2217 
2218 	switch(x = raw_header[2] >> 4) {
2219 		case 0:
2220 			is_unparseable = true;
2221 			break;
2222 		case 1:
2223 			decoder->private_->frame.header.blocksize = 192;
2224 			break;
2225 		case 2:
2226 		case 3:
2227 		case 4:
2228 		case 5:
2229 			decoder->private_->frame.header.blocksize = 576 << (x-2);
2230 			break;
2231 		case 6:
2232 		case 7:
2233 			blocksize_hint = x;
2234 			break;
2235 		case 8:
2236 		case 9:
2237 		case 10:
2238 		case 11:
2239 		case 12:
2240 		case 13:
2241 		case 14:
2242 		case 15:
2243 			decoder->private_->frame.header.blocksize = 256 << (x-8);
2244 			break;
2245 		default:
2246 			FLAC__ASSERT(0);
2247 			break;
2248 	}
2249 
2250 	switch(x = raw_header[2] & 0x0f) {
2251 		case 0:
2252 			if(decoder->private_->has_stream_info)
2253 				decoder->private_->frame.header.sample_rate = decoder->private_->stream_info.data.stream_info.sample_rate;
2254 			else
2255 				is_unparseable = true;
2256 			break;
2257 		case 1:
2258 			decoder->private_->frame.header.sample_rate = 88200;
2259 			break;
2260 		case 2:
2261 			decoder->private_->frame.header.sample_rate = 176400;
2262 			break;
2263 		case 3:
2264 			decoder->private_->frame.header.sample_rate = 192000;
2265 			break;
2266 		case 4:
2267 			decoder->private_->frame.header.sample_rate = 8000;
2268 			break;
2269 		case 5:
2270 			decoder->private_->frame.header.sample_rate = 16000;
2271 			break;
2272 		case 6:
2273 			decoder->private_->frame.header.sample_rate = 22050;
2274 			break;
2275 		case 7:
2276 			decoder->private_->frame.header.sample_rate = 24000;
2277 			break;
2278 		case 8:
2279 			decoder->private_->frame.header.sample_rate = 32000;
2280 			break;
2281 		case 9:
2282 			decoder->private_->frame.header.sample_rate = 44100;
2283 			break;
2284 		case 10:
2285 			decoder->private_->frame.header.sample_rate = 48000;
2286 			break;
2287 		case 11:
2288 			decoder->private_->frame.header.sample_rate = 96000;
2289 			break;
2290 		case 12:
2291 		case 13:
2292 		case 14:
2293 			sample_rate_hint = x;
2294 			break;
2295 		case 15:
2296 			send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
2297 			decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2298 			return true;
2299 		default:
2300 			FLAC__ASSERT(0);
2301 	}
2302 
2303 	x = (unsigned)(raw_header[3] >> 4);
2304 	if(x & 8) {
2305 		decoder->private_->frame.header.channels = 2;
2306 		switch(x & 7) {
2307 			case 0:
2308 				decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_LEFT_SIDE;
2309 				break;
2310 			case 1:
2311 				decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_RIGHT_SIDE;
2312 				break;
2313 			case 2:
2314 				decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_MID_SIDE;
2315 				break;
2316 			default:
2317 				is_unparseable = true;
2318 				break;
2319 		}
2320 	}
2321 	else {
2322 		decoder->private_->frame.header.channels = (unsigned)x + 1;
2323 		decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_INDEPENDENT;
2324 	}
2325 
2326 	switch(x = (unsigned)(raw_header[3] & 0x0e) >> 1) {
2327 		case 0:
2328 			if(decoder->private_->has_stream_info)
2329 				decoder->private_->frame.header.bits_per_sample = decoder->private_->stream_info.data.stream_info.bits_per_sample;
2330 			else
2331 				is_unparseable = true;
2332 			break;
2333 		case 1:
2334 			decoder->private_->frame.header.bits_per_sample = 8;
2335 			break;
2336 		case 2:
2337 			decoder->private_->frame.header.bits_per_sample = 12;
2338 			break;
2339 		case 4:
2340 			decoder->private_->frame.header.bits_per_sample = 16;
2341 			break;
2342 		case 5:
2343 			decoder->private_->frame.header.bits_per_sample = 20;
2344 			break;
2345 		case 6:
2346 			decoder->private_->frame.header.bits_per_sample = 24;
2347 			break;
2348 		case 3:
2349 		case 7:
2350 			is_unparseable = true;
2351 			break;
2352 		default:
2353 			FLAC__ASSERT(0);
2354 			break;
2355 	}
2356 
2357 	/* check to make sure that reserved bit is 0 */
2358 	if(raw_header[3] & 0x01) /* MAGIC NUMBER */
2359 		is_unparseable = true;
2360 
2361 	/* read the frame's starting sample number (or frame number as the case may be) */
2362 	if(
2363 		raw_header[1] & 0x01 ||
2364 		/*@@@ this clause is a concession to the old way of doing variable blocksize; the only known implementation is flake and can probably be removed without inconveniencing anyone */
2365 		(decoder->private_->has_stream_info && decoder->private_->stream_info.data.stream_info.min_blocksize != decoder->private_->stream_info.data.stream_info.max_blocksize)
2366 	) { /* variable blocksize */
2367 		if(!FLAC__bitreader_read_utf8_uint64(decoder->private_->input, &xx, raw_header, &raw_header_len))
2368 			return false; /* read_callback_ sets the state for us */
2369 		if(xx == FLAC__U64L(0xffffffffffffffff)) { /* i.e. non-UTF8 code... */
2370 			decoder->private_->lookahead = raw_header[raw_header_len-1]; /* back up as much as we can */
2371 			decoder->private_->cached = true;
2372 			send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
2373 			decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2374 			return true;
2375 		}
2376 		decoder->private_->frame.header.number_type = FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER;
2377 		decoder->private_->frame.header.number.sample_number = xx;
2378 	}
2379 	else { /* fixed blocksize */
2380 		if(!FLAC__bitreader_read_utf8_uint32(decoder->private_->input, &x, raw_header, &raw_header_len))
2381 			return false; /* read_callback_ sets the state for us */
2382 		if(x == 0xffffffff) { /* i.e. non-UTF8 code... */
2383 			decoder->private_->lookahead = raw_header[raw_header_len-1]; /* back up as much as we can */
2384 			decoder->private_->cached = true;
2385 			send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
2386 			decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2387 			return true;
2388 		}
2389 		decoder->private_->frame.header.number_type = FLAC__FRAME_NUMBER_TYPE_FRAME_NUMBER;
2390 		decoder->private_->frame.header.number.frame_number = x;
2391 	}
2392 
2393 	if(blocksize_hint) {
2394 		if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
2395 			return false; /* read_callback_ sets the state for us */
2396 		raw_header[raw_header_len++] = (FLAC__byte)x;
2397 		if(blocksize_hint == 7) {
2398 			FLAC__uint32 _x;
2399 			if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &_x, 8))
2400 				return false; /* read_callback_ sets the state for us */
2401 			raw_header[raw_header_len++] = (FLAC__byte)_x;
2402 			x = (x << 8) | _x;
2403 		}
2404 		decoder->private_->frame.header.blocksize = x+1;
2405 	}
2406 
2407 	if(sample_rate_hint) {
2408 		if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
2409 			return false; /* read_callback_ sets the state for us */
2410 		raw_header[raw_header_len++] = (FLAC__byte)x;
2411 		if(sample_rate_hint != 12) {
2412 			FLAC__uint32 _x;
2413 			if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &_x, 8))
2414 				return false; /* read_callback_ sets the state for us */
2415 			raw_header[raw_header_len++] = (FLAC__byte)_x;
2416 			x = (x << 8) | _x;
2417 		}
2418 		if(sample_rate_hint == 12)
2419 			decoder->private_->frame.header.sample_rate = x*1000;
2420 		else if(sample_rate_hint == 13)
2421 			decoder->private_->frame.header.sample_rate = x;
2422 		else
2423 			decoder->private_->frame.header.sample_rate = x*10;
2424 	}
2425 
2426 	/* read the CRC-8 byte */
2427 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
2428 		return false; /* read_callback_ sets the state for us */
2429 	crc8 = (FLAC__byte)x;
2430 
2431 	if(FLAC__crc8(raw_header, raw_header_len) != crc8) {
2432 		send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
2433 		decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2434 		return true;
2435 	}
2436 
2437 	/* calculate the sample number from the frame number if needed */
2438 	decoder->private_->next_fixed_block_size = 0;
2439 	if(decoder->private_->frame.header.number_type == FLAC__FRAME_NUMBER_TYPE_FRAME_NUMBER) {
2440 		x = decoder->private_->frame.header.number.frame_number;
2441 		decoder->private_->frame.header.number_type = FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER;
2442 		if(decoder->private_->fixed_block_size)
2443 			decoder->private_->frame.header.number.sample_number = (FLAC__uint64)decoder->private_->fixed_block_size * (FLAC__uint64)x;
2444 		else if(decoder->private_->has_stream_info) {
2445 			if(decoder->private_->stream_info.data.stream_info.min_blocksize == decoder->private_->stream_info.data.stream_info.max_blocksize) {
2446 				decoder->private_->frame.header.number.sample_number = (FLAC__uint64)decoder->private_->stream_info.data.stream_info.min_blocksize * (FLAC__uint64)x;
2447 				decoder->private_->next_fixed_block_size = decoder->private_->stream_info.data.stream_info.max_blocksize;
2448 			}
2449 			else
2450 				is_unparseable = true;
2451 		}
2452 		else if(x == 0) {
2453 			decoder->private_->frame.header.number.sample_number = 0;
2454 			decoder->private_->next_fixed_block_size = decoder->private_->frame.header.blocksize;
2455 		}
2456 		else {
2457 			/* can only get here if the stream has invalid frame numbering and no STREAMINFO, so assume it's not the last (possibly short) frame */
2458 			decoder->private_->frame.header.number.sample_number = (FLAC__uint64)decoder->private_->frame.header.blocksize * (FLAC__uint64)x;
2459 		}
2460 	}
2461 
2462 	if(is_unparseable) {
2463 		send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
2464 		decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2465 		return true;
2466 	}
2467 
2468 	return true;
2469 }
2470 
read_subframe_(FLAC__StreamDecoder * decoder,unsigned channel,unsigned bps,FLAC__bool do_full_decode)2471 FLAC__bool read_subframe_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode)
2472 {
2473 	FLAC__uint32 x;
2474 	FLAC__bool wasted_bits;
2475 	unsigned i;
2476 
2477 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8)) /* MAGIC NUMBER */
2478 		return false; /* read_callback_ sets the state for us */
2479 
2480 	wasted_bits = (x & 1);
2481 	x &= 0xfe;
2482 
2483 	if(wasted_bits) {
2484 		unsigned u;
2485 		if(!FLAC__bitreader_read_unary_unsigned(decoder->private_->input, &u))
2486 			return false; /* read_callback_ sets the state for us */
2487 		decoder->private_->frame.subframes[channel].wasted_bits = u+1;
2488 		if (decoder->private_->frame.subframes[channel].wasted_bits >= bps)
2489 			return false;
2490 		bps -= decoder->private_->frame.subframes[channel].wasted_bits;
2491 	}
2492 	else
2493 		decoder->private_->frame.subframes[channel].wasted_bits = 0;
2494 
2495 	/*
2496 	 * Lots of magic numbers here
2497 	 */
2498 	if(x & 0x80) {
2499 		send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
2500 		decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2501 		return true;
2502 	}
2503 	else if(x == 0) {
2504 		if(!read_subframe_constant_(decoder, channel, bps, do_full_decode))
2505 			return false;
2506 	}
2507 	else if(x == 2) {
2508 		if(!read_subframe_verbatim_(decoder, channel, bps, do_full_decode))
2509 			return false;
2510 	}
2511 	else if(x < 16) {
2512 		send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
2513 		decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2514 		return true;
2515 	}
2516 	else if(x <= 24) {
2517 		if(!read_subframe_fixed_(decoder, channel, bps, (x>>1)&7, do_full_decode))
2518 			return false;
2519 		if(decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) /* means bad sync or got corruption */
2520 			return true;
2521 	}
2522 	else if(x < 64) {
2523 		send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
2524 		decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2525 		return true;
2526 	}
2527 	else {
2528 		if(!read_subframe_lpc_(decoder, channel, bps, ((x>>1)&31)+1, do_full_decode))
2529 			return false;
2530 		if(decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) /* means bad sync or got corruption */
2531 			return true;
2532 	}
2533 
2534 	if(wasted_bits && do_full_decode) {
2535 		x = decoder->private_->frame.subframes[channel].wasted_bits;
2536 		for(i = 0; i < decoder->private_->frame.header.blocksize; i++) {
2537 			uint32_t val = decoder->private_->output[channel][i];
2538 			decoder->private_->output[channel][i] = (val << x);
2539 		}
2540 	}
2541 
2542 	return true;
2543 }
2544 
read_subframe_constant_(FLAC__StreamDecoder * decoder,unsigned channel,unsigned bps,FLAC__bool do_full_decode)2545 FLAC__bool read_subframe_constant_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode)
2546 {
2547 	FLAC__Subframe_Constant *subframe = &decoder->private_->frame.subframes[channel].data.constant;
2548 	FLAC__int32 x;
2549 	unsigned i;
2550 	FLAC__int32 *output = decoder->private_->output[channel];
2551 
2552 	decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_CONSTANT;
2553 
2554 	if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &x, bps))
2555 		return false; /* read_callback_ sets the state for us */
2556 
2557 	subframe->value = x;
2558 
2559 	/* decode the subframe */
2560 	if(do_full_decode) {
2561 		for(i = 0; i < decoder->private_->frame.header.blocksize; i++)
2562 			output[i] = x;
2563 	}
2564 
2565 	return true;
2566 }
2567 
read_subframe_fixed_(FLAC__StreamDecoder * decoder,unsigned channel,unsigned bps,const unsigned order,FLAC__bool do_full_decode)2568 FLAC__bool read_subframe_fixed_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, const unsigned order, FLAC__bool do_full_decode)
2569 {
2570 	FLAC__Subframe_Fixed *subframe = &decoder->private_->frame.subframes[channel].data.fixed;
2571 	FLAC__int32 i32;
2572 	FLAC__uint32 u32;
2573 	unsigned u;
2574 
2575 	decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_FIXED;
2576 
2577 	subframe->residual = decoder->private_->residual[channel];
2578 	subframe->order = order;
2579 
2580 	/* read warm-up samples */
2581 	for(u = 0; u < order; u++) {
2582 		if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i32, bps))
2583 			return false; /* read_callback_ sets the state for us */
2584 		subframe->warmup[u] = i32;
2585 	}
2586 
2587 	/* read entropy coding method info */
2588 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_TYPE_LEN))
2589 		return false; /* read_callback_ sets the state for us */
2590 	subframe->entropy_coding_method.type = (FLAC__EntropyCodingMethodType)u32;
2591 	switch(subframe->entropy_coding_method.type) {
2592 		case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE:
2593 		case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2:
2594 			if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ORDER_LEN))
2595 				return false; /* read_callback_ sets the state for us */
2596 			if(decoder->private_->frame.header.blocksize >> u32 < order) {
2597 				send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
2598 				decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2599 				return true;
2600 			}
2601 			subframe->entropy_coding_method.data.partitioned_rice.order = u32;
2602 			subframe->entropy_coding_method.data.partitioned_rice.contents = &decoder->private_->partitioned_rice_contents[channel];
2603 			break;
2604 		default:
2605 			send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
2606 			decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2607 			return true;
2608 	}
2609 
2610 	/* read residual */
2611 	switch(subframe->entropy_coding_method.type) {
2612 		case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE:
2613 		case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2:
2614 			if(!read_residual_partitioned_rice_(decoder, order, subframe->entropy_coding_method.data.partitioned_rice.order, &decoder->private_->partitioned_rice_contents[channel], decoder->private_->residual[channel], /*is_extended=*/subframe->entropy_coding_method.type == FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2))
2615 				return false;
2616 			break;
2617 		default:
2618 			FLAC__ASSERT(0);
2619 	}
2620 
2621 	/* decode the subframe */
2622 	if(do_full_decode) {
2623 		memcpy(decoder->private_->output[channel], subframe->warmup, sizeof(FLAC__int32) * order);
2624 		FLAC__fixed_restore_signal(decoder->private_->residual[channel], decoder->private_->frame.header.blocksize-order, order, decoder->private_->output[channel]+order);
2625 	}
2626 
2627 	return true;
2628 }
2629 
read_subframe_lpc_(FLAC__StreamDecoder * decoder,unsigned channel,unsigned bps,const unsigned order,FLAC__bool do_full_decode)2630 FLAC__bool read_subframe_lpc_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, const unsigned order, FLAC__bool do_full_decode)
2631 {
2632 	FLAC__Subframe_LPC *subframe = &decoder->private_->frame.subframes[channel].data.lpc;
2633 	FLAC__int32 i32;
2634 	FLAC__uint32 u32;
2635 	unsigned u;
2636 
2637 	decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_LPC;
2638 
2639 	subframe->residual = decoder->private_->residual[channel];
2640 	subframe->order = order;
2641 
2642 	/* read warm-up samples */
2643 	for(u = 0; u < order; u++) {
2644 		if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i32, bps))
2645 			return false; /* read_callback_ sets the state for us */
2646 		subframe->warmup[u] = i32;
2647 	}
2648 
2649 	/* read qlp coeff precision */
2650 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__SUBFRAME_LPC_QLP_COEFF_PRECISION_LEN))
2651 		return false; /* read_callback_ sets the state for us */
2652 	if(u32 == (1u << FLAC__SUBFRAME_LPC_QLP_COEFF_PRECISION_LEN) - 1) {
2653 		send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
2654 		decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2655 		return true;
2656 	}
2657 	subframe->qlp_coeff_precision = u32+1;
2658 
2659 	/* read qlp shift */
2660 	if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i32, FLAC__SUBFRAME_LPC_QLP_SHIFT_LEN))
2661 		return false; /* read_callback_ sets the state for us */
2662 	if(i32 < 0) {
2663 		send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
2664 		decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2665 		return true;
2666 	}
2667 	subframe->quantization_level = i32;
2668 
2669 	/* read quantized lp coefficiencts */
2670 	for(u = 0; u < order; u++) {
2671 		if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i32, subframe->qlp_coeff_precision))
2672 			return false; /* read_callback_ sets the state for us */
2673 		subframe->qlp_coeff[u] = i32;
2674 	}
2675 
2676 	/* read entropy coding method info */
2677 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_TYPE_LEN))
2678 		return false; /* read_callback_ sets the state for us */
2679 	subframe->entropy_coding_method.type = (FLAC__EntropyCodingMethodType)u32;
2680 	switch(subframe->entropy_coding_method.type) {
2681 		case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE:
2682 		case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2:
2683 			if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ORDER_LEN))
2684 				return false; /* read_callback_ sets the state for us */
2685 			if(decoder->private_->frame.header.blocksize >> u32 < order) {
2686 				send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
2687 				decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2688 				return true;
2689 			}
2690 			subframe->entropy_coding_method.data.partitioned_rice.order = u32;
2691 			subframe->entropy_coding_method.data.partitioned_rice.contents = &decoder->private_->partitioned_rice_contents[channel];
2692 			break;
2693 		default:
2694 			send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
2695 			decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2696 			return true;
2697 	}
2698 
2699 	/* read residual */
2700 	switch(subframe->entropy_coding_method.type) {
2701 		case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE:
2702 		case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2:
2703 			if(!read_residual_partitioned_rice_(decoder, order, subframe->entropy_coding_method.data.partitioned_rice.order, &decoder->private_->partitioned_rice_contents[channel], decoder->private_->residual[channel], /*is_extended=*/subframe->entropy_coding_method.type == FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2))
2704 				return false;
2705 			break;
2706 		default:
2707 			FLAC__ASSERT(0);
2708 	}
2709 
2710 	/* decode the subframe */
2711 	if(do_full_decode) {
2712 		memcpy(decoder->private_->output[channel], subframe->warmup, sizeof(FLAC__int32) * order);
2713 		if(bps + subframe->qlp_coeff_precision + FLAC__bitmath_ilog2(order) <= 32)
2714 			if(bps <= 16 && subframe->qlp_coeff_precision <= 16)
2715 				decoder->private_->local_lpc_restore_signal_16bit(decoder->private_->residual[channel], decoder->private_->frame.header.blocksize-order, subframe->qlp_coeff, order, subframe->quantization_level, decoder->private_->output[channel]+order);
2716 			else
2717 				decoder->private_->local_lpc_restore_signal(decoder->private_->residual[channel], decoder->private_->frame.header.blocksize-order, subframe->qlp_coeff, order, subframe->quantization_level, decoder->private_->output[channel]+order);
2718 		else
2719 			decoder->private_->local_lpc_restore_signal_64bit(decoder->private_->residual[channel], decoder->private_->frame.header.blocksize-order, subframe->qlp_coeff, order, subframe->quantization_level, decoder->private_->output[channel]+order);
2720 	}
2721 
2722 	return true;
2723 }
2724 
read_subframe_verbatim_(FLAC__StreamDecoder * decoder,unsigned channel,unsigned bps,FLAC__bool do_full_decode)2725 FLAC__bool read_subframe_verbatim_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode)
2726 {
2727 	FLAC__Subframe_Verbatim *subframe = &decoder->private_->frame.subframes[channel].data.verbatim;
2728 	FLAC__int32 x, *residual = decoder->private_->residual[channel];
2729 	unsigned i;
2730 
2731 	decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_VERBATIM;
2732 
2733 	subframe->data = residual;
2734 
2735 	for(i = 0; i < decoder->private_->frame.header.blocksize; i++) {
2736 		if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &x, bps))
2737 			return false; /* read_callback_ sets the state for us */
2738 		residual[i] = x;
2739 	}
2740 
2741 	/* decode the subframe */
2742 	if(do_full_decode)
2743 		memcpy(decoder->private_->output[channel], subframe->data, sizeof(FLAC__int32) * decoder->private_->frame.header.blocksize);
2744 
2745 	return true;
2746 }
2747 
read_residual_partitioned_rice_(FLAC__StreamDecoder * decoder,unsigned predictor_order,unsigned partition_order,FLAC__EntropyCodingMethod_PartitionedRiceContents * partitioned_rice_contents,FLAC__int32 * residual,FLAC__bool is_extended)2748 FLAC__bool read_residual_partitioned_rice_(FLAC__StreamDecoder *decoder, unsigned predictor_order, unsigned partition_order, FLAC__EntropyCodingMethod_PartitionedRiceContents *partitioned_rice_contents, FLAC__int32 *residual, FLAC__bool is_extended)
2749 {
2750 	FLAC__uint32 rice_parameter;
2751 	int i;
2752 	unsigned partition, sample, u;
2753 	const unsigned partitions = 1u << partition_order;
2754 	const unsigned partition_samples = partition_order > 0? decoder->private_->frame.header.blocksize >> partition_order : decoder->private_->frame.header.blocksize - predictor_order;
2755 	const unsigned plen = is_extended? FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2_PARAMETER_LEN : FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN;
2756 	const unsigned pesc = is_extended? FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2_ESCAPE_PARAMETER : FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ESCAPE_PARAMETER;
2757 
2758 	/* invalid predictor and partition orders mush be handled in the callers */
2759 	FLAC__ASSERT(partition_order > 0? partition_samples >= predictor_order : decoder->private_->frame.header.blocksize >= predictor_order);
2760 
2761 	if(!FLAC__format_entropy_coding_method_partitioned_rice_contents_ensure_size(partitioned_rice_contents, flac_max(6u, partition_order))) {
2762 		decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
2763 		return false;
2764 	}
2765 
2766 	sample = 0;
2767 	for(partition = 0; partition < partitions; partition++) {
2768 		if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &rice_parameter, plen))
2769 			return false; /* read_callback_ sets the state for us */
2770 		partitioned_rice_contents->parameters[partition] = rice_parameter;
2771 		if(rice_parameter < pesc) {
2772 			partitioned_rice_contents->raw_bits[partition] = 0;
2773 			u = (partition_order == 0 || partition > 0)? partition_samples : partition_samples - predictor_order;
2774 			if(!FLAC__bitreader_read_rice_signed_block(decoder->private_->input, residual + sample, u, rice_parameter))
2775 				return false; /* read_callback_ sets the state for us */
2776 			sample += u;
2777 		}
2778 		else {
2779 			if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &rice_parameter, FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_RAW_LEN))
2780 				return false; /* read_callback_ sets the state for us */
2781 			partitioned_rice_contents->raw_bits[partition] = rice_parameter;
2782 			for(u = (partition_order == 0 || partition > 0)? 0 : predictor_order; u < partition_samples; u++, sample++) {
2783 				if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i, rice_parameter))
2784 					return false; /* read_callback_ sets the state for us */
2785 				residual[sample] = i;
2786 			}
2787 		}
2788 	}
2789 
2790 	return true;
2791 }
2792 
read_zero_padding_(FLAC__StreamDecoder * decoder)2793 FLAC__bool read_zero_padding_(FLAC__StreamDecoder *decoder)
2794 {
2795 	if(!FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input)) {
2796 		FLAC__uint32 zero = 0;
2797 		if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &zero, FLAC__bitreader_bits_left_for_byte_alignment(decoder->private_->input)))
2798 			return false; /* read_callback_ sets the state for us */
2799 		if(zero != 0) {
2800 			send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
2801 			decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2802 		}
2803 	}
2804 	return true;
2805 }
2806 
read_callback_(FLAC__byte buffer[],size_t * bytes,void * client_data)2807 FLAC__bool read_callback_(FLAC__byte buffer[], size_t *bytes, void *client_data)
2808 {
2809 	FLAC__StreamDecoder *decoder = (FLAC__StreamDecoder *)client_data;
2810 
2811 	if(
2812 #if FLAC__HAS_OGG
2813 		/* see [1] HACK NOTE below for why we don't call the eof_callback when decoding Ogg FLAC */
2814 		!decoder->private_->is_ogg &&
2815 #endif
2816 		decoder->private_->eof_callback && decoder->private_->eof_callback(decoder, decoder->private_->client_data)
2817 	) {
2818 		*bytes = 0;
2819 		decoder->protected_->state = FLAC__STREAM_DECODER_END_OF_STREAM;
2820 		return false;
2821 	}
2822 	else if(*bytes > 0) {
2823 		/* While seeking, it is possible for our seek to land in the
2824 		 * middle of audio data that looks exactly like a frame header
2825 		 * from a future version of an encoder.  When that happens, our
2826 		 * error callback will get an
2827 		 * FLAC__STREAM_DECODER_UNPARSEABLE_STREAM and increment its
2828 		 * unparseable_frame_count.  But there is a remote possibility
2829 		 * that it is properly synced at such a "future-codec frame",
2830 		 * so to make sure, we wait to see many "unparseable" errors in
2831 		 * a row before bailing out.
2832 		 */
2833 		if(decoder->private_->is_seeking && decoder->private_->unparseable_frame_count > 20) {
2834 			decoder->protected_->state = FLAC__STREAM_DECODER_ABORTED;
2835 			return false;
2836 		}
2837 		else {
2838 			const FLAC__StreamDecoderReadStatus status =
2839 #if FLAC__HAS_OGG
2840 				decoder->private_->is_ogg?
2841 				read_callback_ogg_aspect_(decoder, buffer, bytes) :
2842 #endif
2843 				decoder->private_->read_callback(decoder, buffer, bytes, decoder->private_->client_data)
2844 			;
2845 			if(status == FLAC__STREAM_DECODER_READ_STATUS_ABORT) {
2846 				decoder->protected_->state = FLAC__STREAM_DECODER_ABORTED;
2847 				return false;
2848 			}
2849 			else if(*bytes == 0) {
2850 				if(
2851 					status == FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM ||
2852 					(
2853 #if FLAC__HAS_OGG
2854 						/* see [1] HACK NOTE below for why we don't call the eof_callback when decoding Ogg FLAC */
2855 						!decoder->private_->is_ogg &&
2856 #endif
2857 						decoder->private_->eof_callback && decoder->private_->eof_callback(decoder, decoder->private_->client_data)
2858 					)
2859 				) {
2860 					decoder->protected_->state = FLAC__STREAM_DECODER_END_OF_STREAM;
2861 					return false;
2862 				}
2863 				else
2864 					return true;
2865 			}
2866 			else
2867 				return true;
2868 		}
2869 	}
2870 	else {
2871 		/* abort to avoid a deadlock */
2872 		decoder->protected_->state = FLAC__STREAM_DECODER_ABORTED;
2873 		return false;
2874 	}
2875 	/* [1] @@@ HACK NOTE: The end-of-stream checking has to be hacked around
2876 	 * for Ogg FLAC.  This is because the ogg decoder aspect can lose sync
2877 	 * and at the same time hit the end of the stream (for example, seeking
2878 	 * to a point that is after the beginning of the last Ogg page).  There
2879 	 * is no way to report an Ogg sync loss through the callbacks (see note
2880 	 * in read_callback_ogg_aspect_()) so it returns CONTINUE with *bytes==0.
2881 	 * So to keep the decoder from stopping at this point we gate the call
2882 	 * to the eof_callback and let the Ogg decoder aspect set the
2883 	 * end-of-stream state when it is needed.
2884 	 */
2885 }
2886 
2887 #if FLAC__HAS_OGG
read_callback_ogg_aspect_(const FLAC__StreamDecoder * decoder,FLAC__byte buffer[],size_t * bytes)2888 FLAC__StreamDecoderReadStatus read_callback_ogg_aspect_(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes)
2889 {
2890 	switch(FLAC__ogg_decoder_aspect_read_callback_wrapper(&decoder->protected_->ogg_decoder_aspect, buffer, bytes, read_callback_proxy_, decoder, decoder->private_->client_data)) {
2891 		case FLAC__OGG_DECODER_ASPECT_READ_STATUS_OK:
2892 			return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
2893 		/* we don't really have a way to handle lost sync via read
2894 		 * callback so we'll let it pass and let the underlying
2895 		 * FLAC decoder catch the error
2896 		 */
2897 		case FLAC__OGG_DECODER_ASPECT_READ_STATUS_LOST_SYNC:
2898 			return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
2899 		case FLAC__OGG_DECODER_ASPECT_READ_STATUS_END_OF_STREAM:
2900 			return FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM;
2901 		case FLAC__OGG_DECODER_ASPECT_READ_STATUS_NOT_FLAC:
2902 		case FLAC__OGG_DECODER_ASPECT_READ_STATUS_UNSUPPORTED_MAPPING_VERSION:
2903 		case FLAC__OGG_DECODER_ASPECT_READ_STATUS_ABORT:
2904 		case FLAC__OGG_DECODER_ASPECT_READ_STATUS_ERROR:
2905 		case FLAC__OGG_DECODER_ASPECT_READ_STATUS_MEMORY_ALLOCATION_ERROR:
2906 			return FLAC__STREAM_DECODER_READ_STATUS_ABORT;
2907 		default:
2908 			FLAC__ASSERT(0);
2909 			/* double protection */
2910 			return FLAC__STREAM_DECODER_READ_STATUS_ABORT;
2911 	}
2912 }
2913 
read_callback_proxy_(const void * void_decoder,FLAC__byte buffer[],size_t * bytes,void * client_data)2914 FLAC__OggDecoderAspectReadStatus read_callback_proxy_(const void *void_decoder, FLAC__byte buffer[], size_t *bytes, void *client_data)
2915 {
2916 	FLAC__StreamDecoder *decoder = (FLAC__StreamDecoder*)void_decoder;
2917 
2918 	switch(decoder->private_->read_callback(decoder, buffer, bytes, client_data)) {
2919 		case FLAC__STREAM_DECODER_READ_STATUS_CONTINUE:
2920 			return FLAC__OGG_DECODER_ASPECT_READ_STATUS_OK;
2921 		case FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM:
2922 			return FLAC__OGG_DECODER_ASPECT_READ_STATUS_END_OF_STREAM;
2923 		case FLAC__STREAM_DECODER_READ_STATUS_ABORT:
2924 			return FLAC__OGG_DECODER_ASPECT_READ_STATUS_ABORT;
2925 		default:
2926 			/* double protection: */
2927 			FLAC__ASSERT(0);
2928 			return FLAC__OGG_DECODER_ASPECT_READ_STATUS_ABORT;
2929 	}
2930 }
2931 #endif
2932 
write_audio_frame_to_client_(FLAC__StreamDecoder * decoder,const FLAC__Frame * frame,const FLAC__int32 * const buffer[])2933 FLAC__StreamDecoderWriteStatus write_audio_frame_to_client_(FLAC__StreamDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[])
2934 {
2935 	if(decoder->private_->is_seeking) {
2936 		FLAC__uint64 this_frame_sample = frame->header.number.sample_number;
2937 		FLAC__uint64 next_frame_sample = this_frame_sample + (FLAC__uint64)frame->header.blocksize;
2938 		FLAC__uint64 target_sample = decoder->private_->target_sample;
2939 
2940 		FLAC__ASSERT(frame->header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER);
2941 
2942 #if FLAC__HAS_OGG
2943 		decoder->private_->got_a_frame = true;
2944 #endif
2945 		decoder->private_->last_frame = *frame; /* save the frame */
2946 		if(this_frame_sample <= target_sample && target_sample < next_frame_sample) { /* we hit our target frame */
2947 			unsigned delta = (unsigned)(target_sample - this_frame_sample);
2948 			/* kick out of seek mode */
2949 			decoder->private_->is_seeking = false;
2950 			/* shift out the samples before target_sample */
2951 			if(delta > 0) {
2952 				unsigned channel;
2953 				const FLAC__int32 *newbuffer[FLAC__MAX_CHANNELS];
2954 				for(channel = 0; channel < frame->header.channels; channel++)
2955 					newbuffer[channel] = buffer[channel] + delta;
2956 				decoder->private_->last_frame.header.blocksize -= delta;
2957 				decoder->private_->last_frame.header.number.sample_number += (FLAC__uint64)delta;
2958 				/* write the relevant samples */
2959 				return decoder->private_->write_callback(decoder, &decoder->private_->last_frame, newbuffer, decoder->private_->client_data);
2960 			}
2961 			else {
2962 				/* write the relevant samples */
2963 				return decoder->private_->write_callback(decoder, frame, buffer, decoder->private_->client_data);
2964 			}
2965 		}
2966 		else {
2967 			return FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE;
2968 		}
2969 	}
2970 	else {
2971 		/*
2972 		 * If we never got STREAMINFO, turn off MD5 checking to save
2973 		 * cycles since we don't have a sum to compare to anyway
2974 		 */
2975 		if(!decoder->private_->has_stream_info)
2976 			decoder->private_->do_md5_checking = false;
2977 		if(decoder->private_->do_md5_checking) {
2978 			if(!FLAC__MD5Accumulate(&decoder->private_->md5context, buffer, frame->header.channels, frame->header.blocksize, (frame->header.bits_per_sample+7) / 8))
2979 				return FLAC__STREAM_DECODER_WRITE_STATUS_ABORT;
2980 		}
2981 		return decoder->private_->write_callback(decoder, frame, buffer, decoder->private_->client_data);
2982 	}
2983 }
2984 
send_error_to_client_(const FLAC__StreamDecoder * decoder,FLAC__StreamDecoderErrorStatus status)2985 void send_error_to_client_(const FLAC__StreamDecoder *decoder, FLAC__StreamDecoderErrorStatus status)
2986 {
2987 	if(!decoder->private_->is_seeking)
2988 		decoder->private_->error_callback(decoder, status, decoder->private_->client_data);
2989 	else if(status == FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM)
2990 		decoder->private_->unparseable_frame_count++;
2991 }
2992 
seek_to_absolute_sample_(FLAC__StreamDecoder * decoder,FLAC__uint64 stream_length,FLAC__uint64 target_sample)2993 FLAC__bool seek_to_absolute_sample_(FLAC__StreamDecoder *decoder, FLAC__uint64 stream_length, FLAC__uint64 target_sample)
2994 {
2995 	FLAC__uint64 first_frame_offset = decoder->private_->first_frame_offset, lower_bound, upper_bound, lower_bound_sample, upper_bound_sample, this_frame_sample;
2996 	FLAC__int64 pos = -1;
2997 	int i;
2998 	unsigned approx_bytes_per_frame;
2999 	FLAC__bool first_seek = true;
3000 	const FLAC__uint64 total_samples = FLAC__stream_decoder_get_total_samples(decoder);
3001 	const unsigned min_blocksize = decoder->private_->stream_info.data.stream_info.min_blocksize;
3002 	const unsigned max_blocksize = decoder->private_->stream_info.data.stream_info.max_blocksize;
3003 	const unsigned max_framesize = decoder->private_->stream_info.data.stream_info.max_framesize;
3004 	const unsigned min_framesize = decoder->private_->stream_info.data.stream_info.min_framesize;
3005 	/* take these from the current frame in case they've changed mid-stream */
3006 	unsigned channels = FLAC__stream_decoder_get_channels(decoder);
3007 	unsigned bps = FLAC__stream_decoder_get_bits_per_sample(decoder);
3008 	const FLAC__StreamMetadata_SeekTable *seek_table = decoder->private_->has_seek_table? &decoder->private_->seek_table.data.seek_table : 0;
3009 
3010 	/* use values from stream info if we didn't decode a frame */
3011 	if(channels == 0)
3012 		channels = decoder->private_->stream_info.data.stream_info.channels;
3013 	if(bps == 0)
3014 		bps = decoder->private_->stream_info.data.stream_info.bits_per_sample;
3015 
3016 	/* we are just guessing here */
3017 	if(max_framesize > 0)
3018 		approx_bytes_per_frame = (max_framesize + min_framesize) / 2 + 1;
3019 	/*
3020 	 * Check if it's a known fixed-blocksize stream.  Note that though
3021 	 * the spec doesn't allow zeroes in the STREAMINFO block, we may
3022 	 * never get a STREAMINFO block when decoding so the value of
3023 	 * min_blocksize might be zero.
3024 	 */
3025 	else if(min_blocksize == max_blocksize && min_blocksize > 0) {
3026 		/* note there are no () around 'bps/8' to keep precision up since it's an integer calulation */
3027 		approx_bytes_per_frame = min_blocksize * channels * bps/8 + 64;
3028 	}
3029 	else
3030 		approx_bytes_per_frame = 4096 * channels * bps/8 + 64;
3031 
3032 	/*
3033 	 * First, we set an upper and lower bound on where in the
3034 	 * stream we will search.  For now we assume the worst case
3035 	 * scenario, which is our best guess at the beginning of
3036 	 * the first frame and end of the stream.
3037 	 */
3038 	lower_bound = first_frame_offset;
3039 	lower_bound_sample = 0;
3040 	upper_bound = stream_length;
3041 	upper_bound_sample = total_samples > 0 ? total_samples : target_sample /*estimate it*/;
3042 
3043 	/*
3044 	 * Now we refine the bounds if we have a seektable with
3045 	 * suitable points.  Note that according to the spec they
3046 	 * must be ordered by ascending sample number.
3047 	 *
3048 	 * Note: to protect against invalid seek tables we will ignore points
3049 	 * that have frame_samples==0 or sample_number>=total_samples
3050 	 */
3051 	if(seek_table) {
3052 		FLAC__uint64 new_lower_bound = lower_bound;
3053 		FLAC__uint64 new_upper_bound = upper_bound;
3054 		FLAC__uint64 new_lower_bound_sample = lower_bound_sample;
3055 		FLAC__uint64 new_upper_bound_sample = upper_bound_sample;
3056 
3057 		/* find the closest seek point <= target_sample, if it exists */
3058 		for(i = (int)seek_table->num_points - 1; i >= 0; i--) {
3059 			if(
3060 				seek_table->points[i].sample_number != FLAC__STREAM_METADATA_SEEKPOINT_PLACEHOLDER &&
3061 				seek_table->points[i].frame_samples > 0 && /* defense against bad seekpoints */
3062 				(total_samples <= 0 || seek_table->points[i].sample_number < total_samples) && /* defense against bad seekpoints */
3063 				seek_table->points[i].sample_number <= target_sample
3064 			)
3065 				break;
3066 		}
3067 		if(i >= 0) { /* i.e. we found a suitable seek point... */
3068 			new_lower_bound = first_frame_offset + seek_table->points[i].stream_offset;
3069 			new_lower_bound_sample = seek_table->points[i].sample_number;
3070 		}
3071 
3072 		/* find the closest seek point > target_sample, if it exists */
3073 		for(i = 0; i < (int)seek_table->num_points; i++) {
3074 			if(
3075 				seek_table->points[i].sample_number != FLAC__STREAM_METADATA_SEEKPOINT_PLACEHOLDER &&
3076 				seek_table->points[i].frame_samples > 0 && /* defense against bad seekpoints */
3077 				(total_samples <= 0 || seek_table->points[i].sample_number < total_samples) && /* defense against bad seekpoints */
3078 				seek_table->points[i].sample_number > target_sample
3079 			)
3080 				break;
3081 		}
3082 		if(i < (int)seek_table->num_points) { /* i.e. we found a suitable seek point... */
3083 			new_upper_bound = first_frame_offset + seek_table->points[i].stream_offset;
3084 			new_upper_bound_sample = seek_table->points[i].sample_number;
3085 		}
3086 		/* final protection against unsorted seek tables; keep original values if bogus */
3087 		if(new_upper_bound >= new_lower_bound) {
3088 			lower_bound = new_lower_bound;
3089 			upper_bound = new_upper_bound;
3090 			lower_bound_sample = new_lower_bound_sample;
3091 			upper_bound_sample = new_upper_bound_sample;
3092 		}
3093 	}
3094 
3095 	FLAC__ASSERT(upper_bound_sample >= lower_bound_sample);
3096 	/* there are 2 insidious ways that the following equality occurs, which
3097 	 * we need to fix:
3098 	 *  1) total_samples is 0 (unknown) and target_sample is 0
3099 	 *  2) total_samples is 0 (unknown) and target_sample happens to be
3100 	 *     exactly equal to the last seek point in the seek table; this
3101 	 *     means there is no seek point above it, and upper_bound_samples
3102 	 *     remains equal to the estimate (of target_samples) we made above
3103 	 * in either case it does not hurt to move upper_bound_sample up by 1
3104 	 */
3105 	if(upper_bound_sample == lower_bound_sample)
3106 		upper_bound_sample++;
3107 
3108 	decoder->private_->target_sample = target_sample;
3109 	while(1) {
3110 		/* check if the bounds are still ok */
3111 		if (lower_bound_sample >= upper_bound_sample || lower_bound > upper_bound) {
3112 			decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3113 			return false;
3114 		}
3115 #ifndef FLAC__INTEGER_ONLY_LIBRARY
3116 		pos = (FLAC__int64)lower_bound + (FLAC__int64)((double)(target_sample - lower_bound_sample) / (double)(upper_bound_sample - lower_bound_sample) * (double)(upper_bound - lower_bound)) - approx_bytes_per_frame;
3117 #else
3118 		/* a little less accurate: */
3119 		if(upper_bound - lower_bound < 0xffffffff)
3120 			pos = (FLAC__int64)lower_bound + (FLAC__int64)(((target_sample - lower_bound_sample) * (upper_bound - lower_bound)) / (upper_bound_sample - lower_bound_sample)) - approx_bytes_per_frame;
3121 		else /* @@@ WATCHOUT, ~2TB limit */
3122 			pos = (FLAC__int64)lower_bound + (FLAC__int64)((((target_sample - lower_bound_sample)>>8) * ((upper_bound - lower_bound)>>8)) / ((upper_bound_sample - lower_bound_sample)>>16)) - approx_bytes_per_frame;
3123 #endif
3124 		if(pos >= (FLAC__int64)upper_bound)
3125 			pos = (FLAC__int64)upper_bound - 1;
3126 		if(pos < (FLAC__int64)lower_bound)
3127 			pos = (FLAC__int64)lower_bound;
3128 		if(decoder->private_->seek_callback(decoder, (FLAC__uint64)pos, decoder->private_->client_data) != FLAC__STREAM_DECODER_SEEK_STATUS_OK) {
3129 			decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3130 			return false;
3131 		}
3132 		if(!FLAC__stream_decoder_flush(decoder)) {
3133 			/* above call sets the state for us */
3134 			return false;
3135 		}
3136 		/* Now we need to get a frame.  First we need to reset our
3137 		 * unparseable_frame_count; if we get too many unparseable
3138 		 * frames in a row, the read callback will return
3139 		 * FLAC__STREAM_DECODER_READ_STATUS_ABORT, causing
3140 		 * FLAC__stream_decoder_process_single() to return false.
3141 		 */
3142 		decoder->private_->unparseable_frame_count = 0;
3143 		if(!FLAC__stream_decoder_process_single(decoder) ||
3144 		   decoder->protected_->state == FLAC__STREAM_DECODER_ABORTED) {
3145 			decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3146 			return false;
3147 		}
3148 		/* our write callback will change the state when it gets to the target frame */
3149 		/* actually, we could have got_a_frame if our decoder is at FLAC__STREAM_DECODER_END_OF_STREAM so we need to check for that also */
3150 #if 0
3151 		/*@@@@@@ used to be the following; not clear if the check for end of stream is needed anymore */
3152 		if(decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_SEEKING && decoder->protected_->state != FLAC__STREAM_DECODER_END_OF_STREAM)
3153 			break;
3154 #endif
3155 		if(!decoder->private_->is_seeking)
3156 			break;
3157 
3158 		FLAC__ASSERT(decoder->private_->last_frame.header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER);
3159 		this_frame_sample = decoder->private_->last_frame.header.number.sample_number;
3160 
3161 		if (0 == decoder->private_->samples_decoded || (this_frame_sample + decoder->private_->last_frame.header.blocksize >= upper_bound_sample && !first_seek)) {
3162 			if (pos == (FLAC__int64)lower_bound) {
3163 				/* can't move back any more than the first frame, something is fatally wrong */
3164 				decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3165 				return false;
3166 			}
3167 			/* our last move backwards wasn't big enough, try again */
3168 			approx_bytes_per_frame = approx_bytes_per_frame? approx_bytes_per_frame * 2 : 16;
3169 			continue;
3170 		}
3171 		/* allow one seek over upper bound, so we can get a correct upper_bound_sample for streams with unknown total_samples */
3172 		first_seek = false;
3173 
3174 		/* make sure we are not seeking in corrupted stream */
3175 		if (this_frame_sample < lower_bound_sample) {
3176 			decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3177 			return false;
3178 		}
3179 
3180 		/* we need to narrow the search */
3181 		if(target_sample < this_frame_sample) {
3182 			upper_bound_sample = this_frame_sample + decoder->private_->last_frame.header.blocksize;
3183 /*@@@@@@ what will decode position be if at end of stream? */
3184 			if(!FLAC__stream_decoder_get_decode_position(decoder, &upper_bound)) {
3185 				decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3186 				return false;
3187 			}
3188 			approx_bytes_per_frame = (unsigned)(2 * (upper_bound - pos) / 3 + 16);
3189 		}
3190 		else { /* target_sample >= this_frame_sample + this frame's blocksize */
3191 			lower_bound_sample = this_frame_sample + decoder->private_->last_frame.header.blocksize;
3192 			if(!FLAC__stream_decoder_get_decode_position(decoder, &lower_bound)) {
3193 				decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3194 				return false;
3195 			}
3196 			approx_bytes_per_frame = (unsigned)(2 * (lower_bound - pos) / 3 + 16);
3197 		}
3198 	}
3199 
3200 	return true;
3201 }
3202 
3203 #if FLAC__HAS_OGG
seek_to_absolute_sample_ogg_(FLAC__StreamDecoder * decoder,FLAC__uint64 stream_length,FLAC__uint64 target_sample)3204 FLAC__bool seek_to_absolute_sample_ogg_(FLAC__StreamDecoder *decoder, FLAC__uint64 stream_length, FLAC__uint64 target_sample)
3205 {
3206 	FLAC__uint64 left_pos = 0, right_pos = stream_length;
3207 	FLAC__uint64 left_sample = 0, right_sample = FLAC__stream_decoder_get_total_samples(decoder);
3208 	FLAC__uint64 this_frame_sample = (FLAC__uint64)0 - 1;
3209 	FLAC__uint64 pos = 0; /* only initialized to avoid compiler warning */
3210 	FLAC__bool did_a_seek;
3211 	unsigned iteration = 0;
3212 
3213 	/* In the first iterations, we will calculate the target byte position
3214 	 * by the distance from the target sample to left_sample and
3215 	 * right_sample (let's call it "proportional search").  After that, we
3216 	 * will switch to binary search.
3217 	 */
3218 	unsigned BINARY_SEARCH_AFTER_ITERATION = 2;
3219 
3220 	/* We will switch to a linear search once our current sample is less
3221 	 * than this number of samples ahead of the target sample
3222 	 */
3223 	static const FLAC__uint64 LINEAR_SEARCH_WITHIN_SAMPLES = FLAC__MAX_BLOCK_SIZE * 2;
3224 
3225 	/* If the total number of samples is unknown, use a large value, and
3226 	 * force binary search immediately.
3227 	 */
3228 	if(right_sample == 0) {
3229 		right_sample = (FLAC__uint64)(-1);
3230 		BINARY_SEARCH_AFTER_ITERATION = 0;
3231 	}
3232 
3233 	decoder->private_->target_sample = target_sample;
3234 	for( ; ; iteration++) {
3235 		if (iteration == 0 || this_frame_sample > target_sample || target_sample - this_frame_sample > LINEAR_SEARCH_WITHIN_SAMPLES) {
3236 			if (iteration >= BINARY_SEARCH_AFTER_ITERATION) {
3237 				pos = (right_pos + left_pos) / 2;
3238 			}
3239 			else {
3240 #ifndef FLAC__INTEGER_ONLY_LIBRARY
3241 				pos = (FLAC__uint64)((double)(target_sample - left_sample) / (double)(right_sample - left_sample) * (double)(right_pos - left_pos));
3242 #else
3243 				/* a little less accurate: */
3244 				if ((target_sample-left_sample <= 0xffffffff) && (right_pos-left_pos <= 0xffffffff))
3245 					pos = (FLAC__int64)(((target_sample-left_sample) * (right_pos-left_pos)) / (right_sample-left_sample));
3246 				else /* @@@ WATCHOUT, ~2TB limit */
3247 					pos = (FLAC__int64)((((target_sample-left_sample)>>8) * ((right_pos-left_pos)>>8)) / ((right_sample-left_sample)>>16));
3248 #endif
3249 				/* @@@ TODO: might want to limit pos to some distance
3250 				 * before EOF, to make sure we land before the last frame,
3251 				 * thereby getting a this_frame_sample and so having a better
3252 				 * estimate.
3253 				 */
3254 			}
3255 
3256 			/* physical seek */
3257 			if(decoder->private_->seek_callback((FLAC__StreamDecoder*)decoder, (FLAC__uint64)pos, decoder->private_->client_data) != FLAC__STREAM_DECODER_SEEK_STATUS_OK) {
3258 				decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3259 				return false;
3260 			}
3261 			if(!FLAC__stream_decoder_flush(decoder)) {
3262 				/* above call sets the state for us */
3263 				return false;
3264 			}
3265 			did_a_seek = true;
3266 		}
3267 		else
3268 			did_a_seek = false;
3269 
3270 		decoder->private_->got_a_frame = false;
3271 		if(!FLAC__stream_decoder_process_single(decoder) ||
3272 		   decoder->protected_->state == FLAC__STREAM_DECODER_ABORTED) {
3273 			decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3274 			return false;
3275 		}
3276 		if(!decoder->private_->got_a_frame) {
3277 			if(did_a_seek) {
3278 				/* this can happen if we seek to a point after the last frame; we drop
3279 				 * to binary search right away in this case to avoid any wasted
3280 				 * iterations of proportional search.
3281 				 */
3282 				right_pos = pos;
3283 				BINARY_SEARCH_AFTER_ITERATION = 0;
3284 			}
3285 			else {
3286 				/* this can probably only happen if total_samples is unknown and the
3287 				 * target_sample is past the end of the stream
3288 				 */
3289 				decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3290 				return false;
3291 			}
3292 		}
3293 		/* our write callback will change the state when it gets to the target frame */
3294 		else if(!decoder->private_->is_seeking) {
3295 			break;
3296 		}
3297 		else {
3298 			this_frame_sample = decoder->private_->last_frame.header.number.sample_number;
3299 			FLAC__ASSERT(decoder->private_->last_frame.header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER);
3300 
3301 			if (did_a_seek) {
3302 				if (this_frame_sample <= target_sample) {
3303 					/* The 'equal' case should not happen, since
3304 					 * FLAC__stream_decoder_process_single()
3305 					 * should recognize that it has hit the
3306 					 * target sample and we would exit through
3307 					 * the 'break' above.
3308 					 */
3309 					FLAC__ASSERT(this_frame_sample != target_sample);
3310 
3311 					left_sample = this_frame_sample;
3312 					/* sanity check to avoid infinite loop */
3313 					if (left_pos == pos) {
3314 						decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3315 						return false;
3316 					}
3317 					left_pos = pos;
3318 				}
3319 				else if(this_frame_sample > target_sample) {
3320 					right_sample = this_frame_sample;
3321 					/* sanity check to avoid infinite loop */
3322 					if (right_pos == pos) {
3323 						decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3324 						return false;
3325 					}
3326 					right_pos = pos;
3327 				}
3328 			}
3329 		}
3330 	}
3331 
3332 	return true;
3333 }
3334 #endif
3335 
file_read_callback_(const FLAC__StreamDecoder * decoder,FLAC__byte buffer[],size_t * bytes,void * client_data)3336 FLAC__StreamDecoderReadStatus file_read_callback_(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes, void *client_data)
3337 {
3338 	(void)client_data;
3339 
3340 	if(*bytes > 0) {
3341 		*bytes = fread(buffer, sizeof(FLAC__byte), *bytes, decoder->private_->file);
3342 		if(ferror(decoder->private_->file))
3343 			return FLAC__STREAM_DECODER_READ_STATUS_ABORT;
3344 		else if(*bytes == 0)
3345 			return FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM;
3346 		else
3347 			return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
3348 	}
3349 	else
3350 		return FLAC__STREAM_DECODER_READ_STATUS_ABORT; /* abort to avoid a deadlock */
3351 }
3352 
file_seek_callback_(const FLAC__StreamDecoder * decoder,FLAC__uint64 absolute_byte_offset,void * client_data)3353 FLAC__StreamDecoderSeekStatus file_seek_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 absolute_byte_offset, void *client_data)
3354 {
3355 	(void)client_data;
3356 
3357 	if(decoder->private_->file == stdin)
3358 		return FLAC__STREAM_DECODER_SEEK_STATUS_UNSUPPORTED;
3359 	else if(fseeko(decoder->private_->file, (FLAC__off_t)absolute_byte_offset, SEEK_SET) < 0)
3360 		return FLAC__STREAM_DECODER_SEEK_STATUS_ERROR;
3361 	else
3362 		return FLAC__STREAM_DECODER_SEEK_STATUS_OK;
3363 }
3364 
file_tell_callback_(const FLAC__StreamDecoder * decoder,FLAC__uint64 * absolute_byte_offset,void * client_data)3365 FLAC__StreamDecoderTellStatus file_tell_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 *absolute_byte_offset, void *client_data)
3366 {
3367 	FLAC__off_t pos;
3368 	(void)client_data;
3369 
3370 	if(decoder->private_->file == stdin)
3371 		return FLAC__STREAM_DECODER_TELL_STATUS_UNSUPPORTED;
3372 	else if((pos = ftello(decoder->private_->file)) < 0)
3373 		return FLAC__STREAM_DECODER_TELL_STATUS_ERROR;
3374 	else {
3375 		*absolute_byte_offset = (FLAC__uint64)pos;
3376 		return FLAC__STREAM_DECODER_TELL_STATUS_OK;
3377 	}
3378 }
3379 
file_length_callback_(const FLAC__StreamDecoder * decoder,FLAC__uint64 * stream_length,void * client_data)3380 FLAC__StreamDecoderLengthStatus file_length_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 *stream_length, void *client_data)
3381 {
3382 	struct flac_stat_s filestats;
3383 	(void)client_data;
3384 
3385 	if(decoder->private_->file == stdin)
3386 		return FLAC__STREAM_DECODER_LENGTH_STATUS_UNSUPPORTED;
3387 	else if(flac_fstat(fileno(decoder->private_->file), &filestats) != 0)
3388 		return FLAC__STREAM_DECODER_LENGTH_STATUS_ERROR;
3389 	else {
3390 		*stream_length = (FLAC__uint64)filestats.st_size;
3391 		return FLAC__STREAM_DECODER_LENGTH_STATUS_OK;
3392 	}
3393 }
3394 
file_eof_callback_(const FLAC__StreamDecoder * decoder,void * client_data)3395 FLAC__bool file_eof_callback_(const FLAC__StreamDecoder *decoder, void *client_data)
3396 {
3397 	(void)client_data;
3398 
3399 	return feof(decoder->private_->file)? true : false;
3400 }
3401