1 /* libFLAC - Free Lossless Audio Codec library
2  * Copyright (C) 2000-2009  Josh Coalson
3  * Copyright (C) 2011-2014  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 =
60 #if FLAC__HAS_OGG
61 	1
62 #else
63 	0
64 #endif
65 ;
66 
67 
68 /***********************************************************************
69  *
70  * Private static data
71  *
72  ***********************************************************************/
73 
74 static const FLAC__byte ID3V2_TAG_[3] = { 'I', 'D', '3' };
75 
76 /***********************************************************************
77  *
78  * Private class method prototypes
79  *
80  ***********************************************************************/
81 
82 static void set_defaults_(FLAC__StreamDecoder *decoder);
83 static FILE *get_binary_stdin_(void);
84 static FLAC__bool allocate_output_(FLAC__StreamDecoder *decoder, unsigned size, unsigned channels);
85 static FLAC__bool has_id_filtered_(FLAC__StreamDecoder *decoder, FLAC__byte *id);
86 static FLAC__bool find_metadata_(FLAC__StreamDecoder *decoder);
87 static FLAC__bool read_metadata_(FLAC__StreamDecoder *decoder);
88 static FLAC__bool read_metadata_streaminfo_(FLAC__StreamDecoder *decoder, FLAC__bool is_last, unsigned length);
89 static FLAC__bool read_metadata_seektable_(FLAC__StreamDecoder *decoder, FLAC__bool is_last, unsigned length);
90 static FLAC__bool read_metadata_vorbiscomment_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_VorbisComment *obj, unsigned length);
91 static FLAC__bool read_metadata_cuesheet_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_CueSheet *obj);
92 static FLAC__bool read_metadata_picture_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_Picture *obj);
93 static FLAC__bool skip_id3v2_tag_(FLAC__StreamDecoder *decoder);
94 static FLAC__bool frame_sync_(FLAC__StreamDecoder *decoder);
95 static FLAC__bool read_frame_(FLAC__StreamDecoder *decoder, FLAC__bool *got_a_frame, FLAC__bool do_full_decode);
96 static FLAC__bool read_frame_header_(FLAC__StreamDecoder *decoder);
97 static FLAC__bool read_subframe_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode);
98 static FLAC__bool read_subframe_constant_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode);
99 static FLAC__bool read_subframe_fixed_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, const unsigned order, FLAC__bool do_full_decode);
100 static FLAC__bool read_subframe_lpc_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, const unsigned order, FLAC__bool do_full_decode);
101 static FLAC__bool read_subframe_verbatim_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode);
102 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);
103 static FLAC__bool read_zero_padding_(FLAC__StreamDecoder *decoder);
104 static FLAC__bool read_callback_(FLAC__byte buffer[], size_t *bytes, void *client_data);
105 #if FLAC__HAS_OGG
106 static FLAC__StreamDecoderReadStatus read_callback_ogg_aspect_(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes);
107 static FLAC__OggDecoderAspectReadStatus read_callback_proxy_(const void *void_decoder, FLAC__byte buffer[], size_t *bytes, void *client_data);
108 #endif
109 static FLAC__StreamDecoderWriteStatus write_audio_frame_to_client_(FLAC__StreamDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[]);
110 static void send_error_to_client_(const FLAC__StreamDecoder *decoder, FLAC__StreamDecoderErrorStatus status);
111 static FLAC__bool seek_to_absolute_sample_(FLAC__StreamDecoder *decoder, FLAC__uint64 stream_length, FLAC__uint64 target_sample);
112 #if FLAC__HAS_OGG
113 static FLAC__bool seek_to_absolute_sample_ogg_(FLAC__StreamDecoder *decoder, FLAC__uint64 stream_length, FLAC__uint64 target_sample);
114 #endif
115 static FLAC__StreamDecoderReadStatus file_read_callback_(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes, void *client_data);
116 static FLAC__StreamDecoderSeekStatus file_seek_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 absolute_byte_offset, void *client_data);
117 static FLAC__StreamDecoderTellStatus file_tell_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 *absolute_byte_offset, void *client_data);
118 static FLAC__StreamDecoderLengthStatus file_length_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 *stream_length, void *client_data);
119 static FLAC__bool file_eof_callback_(const FLAC__StreamDecoder *decoder, void *client_data);
120 
121 /***********************************************************************
122  *
123  * Private class data
124  *
125  ***********************************************************************/
126 
127 typedef struct FLAC__StreamDecoderPrivate {
128 #if FLAC__HAS_OGG
129 	FLAC__bool is_ogg;
130 #endif
131 	FLAC__StreamDecoderReadCallback read_callback;
132 	FLAC__StreamDecoderSeekCallback seek_callback;
133 	FLAC__StreamDecoderTellCallback tell_callback;
134 	FLAC__StreamDecoderLengthCallback length_callback;
135 	FLAC__StreamDecoderEofCallback eof_callback;
136 	FLAC__StreamDecoderWriteCallback write_callback;
137 	FLAC__StreamDecoderMetadataCallback metadata_callback;
138 	FLAC__StreamDecoderErrorCallback error_callback;
139 	/* generic 32-bit datapath: */
140 	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[]);
141 	/* generic 64-bit datapath: */
142 	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[]);
143 	/* for use when the signal is <= 16 bits-per-sample, or <= 15 bits-per-sample on a side channel (which requires 1 extra bit): */
144 	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[]);
145 	void *client_data;
146 	FILE *file; /* only used if FLAC__stream_decoder_init_file()/FLAC__stream_decoder_init_file() called, else NULL */
147 	FLAC__BitReader *input;
148 	FLAC__int32 *output[FLAC__MAX_CHANNELS];
149 	FLAC__int32 *residual[FLAC__MAX_CHANNELS]; /* WATCHOUT: these are the aligned pointers; the real pointers that should be free()'d are residual_unaligned[] below */
150 	FLAC__EntropyCodingMethod_PartitionedRiceContents partitioned_rice_contents[FLAC__MAX_CHANNELS];
151 	unsigned output_capacity, output_channels;
152 	FLAC__uint32 fixed_block_size, next_fixed_block_size;
153 	FLAC__uint64 samples_decoded;
154 	FLAC__bool has_stream_info, has_seek_table;
155 	FLAC__StreamMetadata stream_info;
156 	FLAC__StreamMetadata seek_table;
157 	FLAC__bool metadata_filter[128]; /* MAGIC number 128 == total number of metadata block types == 1 << 7 */
158 	FLAC__byte *metadata_filter_ids;
159 	size_t metadata_filter_ids_count, metadata_filter_ids_capacity; /* units for both are IDs, not bytes */
160 	FLAC__Frame frame;
161 	FLAC__bool cached; /* true if there is a byte in lookahead */
162 	FLAC__CPUInfo cpuinfo;
163 	FLAC__byte header_warmup[2]; /* contains the sync code and reserved bits */
164 	FLAC__byte lookahead; /* temp storage when we need to look ahead one byte in the stream */
165 	/* unaligned (original) pointers to allocated data */
166 	FLAC__int32 *residual_unaligned[FLAC__MAX_CHANNELS];
167 	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 */
168 	FLAC__bool internal_reset_hack; /* used only during init() so we can call reset to set up the decoder without rewinding the input */
169 	FLAC__bool is_seeking;
170 	FLAC__MD5Context md5context;
171 	FLAC__byte computed_md5sum[16]; /* this is the sum we computed from the decoded data */
172 	/* (the rest of these are only used for seeking) */
173 	FLAC__Frame last_frame; /* holds the info of the last frame we seeked to */
174 	FLAC__uint64 first_frame_offset; /* hint to the seek routine of where in the stream the first audio frame starts */
175 	FLAC__uint64 target_sample;
176 	unsigned unparseable_frame_count; /* used to tell whether we're decoding a future version of FLAC or just got a bad sync */
177 #if FLAC__HAS_OGG
178 	FLAC__bool got_a_frame; /* hack needed in Ogg FLAC seek routine to check when process_single() actually writes a frame */
179 #endif
180 } FLAC__StreamDecoderPrivate;
181 
182 /***********************************************************************
183  *
184  * Public static class data
185  *
186  ***********************************************************************/
187 
188 FLAC_API const char * const FLAC__StreamDecoderStateString[] = {
189 	"FLAC__STREAM_DECODER_SEARCH_FOR_METADATA",
190 	"FLAC__STREAM_DECODER_READ_METADATA",
191 	"FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC",
192 	"FLAC__STREAM_DECODER_READ_FRAME",
193 	"FLAC__STREAM_DECODER_END_OF_STREAM",
194 	"FLAC__STREAM_DECODER_OGG_ERROR",
195 	"FLAC__STREAM_DECODER_SEEK_ERROR",
196 	"FLAC__STREAM_DECODER_ABORTED",
197 	"FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR",
198 	"FLAC__STREAM_DECODER_UNINITIALIZED"
199 };
200 
201 FLAC_API const char * const FLAC__StreamDecoderInitStatusString[] = {
202 	"FLAC__STREAM_DECODER_INIT_STATUS_OK",
203 	"FLAC__STREAM_DECODER_INIT_STATUS_UNSUPPORTED_CONTAINER",
204 	"FLAC__STREAM_DECODER_INIT_STATUS_INVALID_CALLBACKS",
205 	"FLAC__STREAM_DECODER_INIT_STATUS_MEMORY_ALLOCATION_ERROR",
206 	"FLAC__STREAM_DECODER_INIT_STATUS_ERROR_OPENING_FILE",
207 	"FLAC__STREAM_DECODER_INIT_STATUS_ALREADY_INITIALIZED"
208 };
209 
210 FLAC_API const char * const FLAC__StreamDecoderReadStatusString[] = {
211 	"FLAC__STREAM_DECODER_READ_STATUS_CONTINUE",
212 	"FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM",
213 	"FLAC__STREAM_DECODER_READ_STATUS_ABORT"
214 };
215 
216 FLAC_API const char * const FLAC__StreamDecoderSeekStatusString[] = {
217 	"FLAC__STREAM_DECODER_SEEK_STATUS_OK",
218 	"FLAC__STREAM_DECODER_SEEK_STATUS_ERROR",
219 	"FLAC__STREAM_DECODER_SEEK_STATUS_UNSUPPORTED"
220 };
221 
222 FLAC_API const char * const FLAC__StreamDecoderTellStatusString[] = {
223 	"FLAC__STREAM_DECODER_TELL_STATUS_OK",
224 	"FLAC__STREAM_DECODER_TELL_STATUS_ERROR",
225 	"FLAC__STREAM_DECODER_TELL_STATUS_UNSUPPORTED"
226 };
227 
228 FLAC_API const char * const FLAC__StreamDecoderLengthStatusString[] = {
229 	"FLAC__STREAM_DECODER_LENGTH_STATUS_OK",
230 	"FLAC__STREAM_DECODER_LENGTH_STATUS_ERROR",
231 	"FLAC__STREAM_DECODER_LENGTH_STATUS_UNSUPPORTED"
232 };
233 
234 FLAC_API const char * const FLAC__StreamDecoderWriteStatusString[] = {
235 	"FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE",
236 	"FLAC__STREAM_DECODER_WRITE_STATUS_ABORT"
237 };
238 
239 FLAC_API const char * const FLAC__StreamDecoderErrorStatusString[] = {
240 	"FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC",
241 	"FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER",
242 	"FLAC__STREAM_DECODER_ERROR_STATUS_FRAME_CRC_MISMATCH",
243 	"FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM"
244 };
245 
246 /***********************************************************************
247  *
248  * Class constructor/destructor
249  *
250  ***********************************************************************/
FLAC__stream_decoder_new(void)251 FLAC_API FLAC__StreamDecoder *FLAC__stream_decoder_new(void)
252 {
253 	FLAC__StreamDecoder *decoder;
254 	unsigned i;
255 
256 	FLAC__ASSERT(sizeof(int) >= 4); /* we want to die right away if this is not true */
257 
258 	decoder = calloc(1, sizeof(FLAC__StreamDecoder));
259 	if(decoder == 0) {
260 		return 0;
261 	}
262 
263 	decoder->protected_ = calloc(1, sizeof(FLAC__StreamDecoderProtected));
264 	if(decoder->protected_ == 0) {
265 		free(decoder);
266 		return 0;
267 	}
268 
269 	decoder->private_ = calloc(1, sizeof(FLAC__StreamDecoderPrivate));
270 	if(decoder->private_ == 0) {
271 		free(decoder->protected_);
272 		free(decoder);
273 		return 0;
274 	}
275 
276 	decoder->private_->input = FLAC__bitreader_new();
277 	if(decoder->private_->input == 0) {
278 		free(decoder->private_);
279 		free(decoder->protected_);
280 		free(decoder);
281 		return 0;
282 	}
283 
284 	decoder->private_->metadata_filter_ids_capacity = 16;
285 	if(0 == (decoder->private_->metadata_filter_ids = malloc((FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8) * decoder->private_->metadata_filter_ids_capacity))) {
286 		FLAC__bitreader_delete(decoder->private_->input);
287 		free(decoder->private_);
288 		free(decoder->protected_);
289 		free(decoder);
290 		return 0;
291 	}
292 
293 	for(i = 0; i < FLAC__MAX_CHANNELS; i++) {
294 		decoder->private_->output[i] = 0;
295 		decoder->private_->residual_unaligned[i] = decoder->private_->residual[i] = 0;
296 	}
297 
298 	decoder->private_->output_capacity = 0;
299 	decoder->private_->output_channels = 0;
300 	decoder->private_->has_seek_table = false;
301 
302 	for(i = 0; i < FLAC__MAX_CHANNELS; i++)
303 		FLAC__format_entropy_coding_method_partitioned_rice_contents_init(&decoder->private_->partitioned_rice_contents[i]);
304 
305 	decoder->private_->file = 0;
306 
307 	set_defaults_(decoder);
308 
309 	decoder->protected_->state = FLAC__STREAM_DECODER_UNINITIALIZED;
310 
311 	return decoder;
312 }
313 
FLAC__stream_decoder_delete(FLAC__StreamDecoder * decoder)314 FLAC_API void FLAC__stream_decoder_delete(FLAC__StreamDecoder *decoder)
315 {
316 	unsigned i;
317 
318 	if (decoder == NULL)
319 		return ;
320 
321 	FLAC__ASSERT(0 != decoder->protected_);
322 	FLAC__ASSERT(0 != decoder->private_);
323 	FLAC__ASSERT(0 != decoder->private_->input);
324 
325 	(void)FLAC__stream_decoder_finish(decoder);
326 
327 	if(0 != decoder->private_->metadata_filter_ids)
328 		free(decoder->private_->metadata_filter_ids);
329 
330 	FLAC__bitreader_delete(decoder->private_->input);
331 
332 	for(i = 0; i < FLAC__MAX_CHANNELS; i++)
333 		FLAC__format_entropy_coding_method_partitioned_rice_contents_clear(&decoder->private_->partitioned_rice_contents[i]);
334 
335 	free(decoder->private_);
336 	free(decoder->protected_);
337 	free(decoder);
338 }
339 
340 /***********************************************************************
341  *
342  * Public class methods
343  *
344  ***********************************************************************/
345 
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)346 static FLAC__StreamDecoderInitStatus init_stream_internal_(
347 	FLAC__StreamDecoder *decoder,
348 	FLAC__StreamDecoderReadCallback read_callback,
349 	FLAC__StreamDecoderSeekCallback seek_callback,
350 	FLAC__StreamDecoderTellCallback tell_callback,
351 	FLAC__StreamDecoderLengthCallback length_callback,
352 	FLAC__StreamDecoderEofCallback eof_callback,
353 	FLAC__StreamDecoderWriteCallback write_callback,
354 	FLAC__StreamDecoderMetadataCallback metadata_callback,
355 	FLAC__StreamDecoderErrorCallback error_callback,
356 	void *client_data,
357 	FLAC__bool is_ogg
358 )
359 {
360 	FLAC__ASSERT(0 != decoder);
361 
362 	if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
363 		return FLAC__STREAM_DECODER_INIT_STATUS_ALREADY_INITIALIZED;
364 
365 #if !FLAC__HAS_OGG
366 	if(is_ogg)
367 		return FLAC__STREAM_DECODER_INIT_STATUS_UNSUPPORTED_CONTAINER;
368 #endif
369 
370 	if(
371 		0 == read_callback ||
372 		0 == write_callback ||
373 		0 == error_callback ||
374 		(seek_callback && (0 == tell_callback || 0 == length_callback || 0 == eof_callback))
375 	)
376 		return FLAC__STREAM_DECODER_INIT_STATUS_INVALID_CALLBACKS;
377 
378 #if FLAC__HAS_OGG
379 	decoder->private_->is_ogg = is_ogg;
380 	if(is_ogg && !FLAC__ogg_decoder_aspect_init(&decoder->protected_->ogg_decoder_aspect))
381 		return decoder->protected_->initstate = FLAC__STREAM_DECODER_INIT_STATUS_ERROR_OPENING_FILE;
382 #endif
383 
384 	/*
385 	 * get the CPU info and set the function pointers
386 	 */
387 	FLAC__cpu_info(&decoder->private_->cpuinfo);
388 	/* first default to the non-asm routines */
389 	decoder->private_->local_lpc_restore_signal = FLAC__lpc_restore_signal;
390 	decoder->private_->local_lpc_restore_signal_64bit = FLAC__lpc_restore_signal_wide;
391 	decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal;
392 	/* now override with asm where appropriate */
393 #ifndef FLAC__NO_ASM
394 	if(decoder->private_->cpuinfo.use_asm) {
395 #ifdef FLAC__CPU_IA32
396 		FLAC__ASSERT(decoder->private_->cpuinfo.type == FLAC__CPUINFO_TYPE_IA32);
397 #ifdef FLAC__HAS_NASM
398 		decoder->private_->local_lpc_restore_signal_64bit = FLAC__lpc_restore_signal_wide_asm_ia32; /* OPT_IA32: was really necessary for GCC < 4.9 */
399 		if(decoder->private_->cpuinfo.ia32.mmx) {
400 			decoder->private_->local_lpc_restore_signal = FLAC__lpc_restore_signal_asm_ia32;
401 			decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal_asm_ia32_mmx;
402 		}
403 		else {
404 			decoder->private_->local_lpc_restore_signal = FLAC__lpc_restore_signal_asm_ia32;
405 			decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal_asm_ia32;
406 		}
407 #endif
408 #ifdef FLAC__HAS_X86INTRIN
409 # if defined FLAC__SSE2_SUPPORTED && !defined FLAC__HAS_NASM /* OPT_SSE: not better than MMX asm */
410 		if(decoder->private_->cpuinfo.ia32.sse2) {
411 			decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal_16_intrin_sse2;
412 		}
413 # endif
414 # if defined FLAC__SSE4_1_SUPPORTED
415 		if(decoder->private_->cpuinfo.ia32.sse41) {
416 			decoder->private_->local_lpc_restore_signal_64bit = FLAC__lpc_restore_signal_wide_intrin_sse41;
417 		}
418 # endif
419 #endif
420 #elif defined FLAC__CPU_X86_64
421 		FLAC__ASSERT(decoder->private_->cpuinfo.type == FLAC__CPUINFO_TYPE_X86_64);
422 		/* No useful SSE optimizations yet */
423 #endif
424 	}
425 #endif
426 
427 	/* from here on, errors are fatal */
428 
429 	if(!FLAC__bitreader_init(decoder->private_->input, read_callback_, decoder)) {
430 		decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
431 		return FLAC__STREAM_DECODER_INIT_STATUS_MEMORY_ALLOCATION_ERROR;
432 	}
433 
434 	decoder->private_->read_callback = read_callback;
435 	decoder->private_->seek_callback = seek_callback;
436 	decoder->private_->tell_callback = tell_callback;
437 	decoder->private_->length_callback = length_callback;
438 	decoder->private_->eof_callback = eof_callback;
439 	decoder->private_->write_callback = write_callback;
440 	decoder->private_->metadata_callback = metadata_callback;
441 	decoder->private_->error_callback = error_callback;
442 	decoder->private_->client_data = client_data;
443 	decoder->private_->fixed_block_size = decoder->private_->next_fixed_block_size = 0;
444 	decoder->private_->samples_decoded = 0;
445 	decoder->private_->has_stream_info = false;
446 	decoder->private_->cached = false;
447 
448 	decoder->private_->do_md5_checking = decoder->protected_->md5_checking;
449 	decoder->private_->is_seeking = false;
450 
451 	decoder->private_->internal_reset_hack = true; /* so the following reset does not try to rewind the input */
452 	if(!FLAC__stream_decoder_reset(decoder)) {
453 		/* above call sets the state for us */
454 		return FLAC__STREAM_DECODER_INIT_STATUS_MEMORY_ALLOCATION_ERROR;
455 	}
456 
457 	return FLAC__STREAM_DECODER_INIT_STATUS_OK;
458 }
459 
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)460 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_stream(
461 	FLAC__StreamDecoder *decoder,
462 	FLAC__StreamDecoderReadCallback read_callback,
463 	FLAC__StreamDecoderSeekCallback seek_callback,
464 	FLAC__StreamDecoderTellCallback tell_callback,
465 	FLAC__StreamDecoderLengthCallback length_callback,
466 	FLAC__StreamDecoderEofCallback eof_callback,
467 	FLAC__StreamDecoderWriteCallback write_callback,
468 	FLAC__StreamDecoderMetadataCallback metadata_callback,
469 	FLAC__StreamDecoderErrorCallback error_callback,
470 	void *client_data
471 )
472 {
473 	return init_stream_internal_(
474 		decoder,
475 		read_callback,
476 		seek_callback,
477 		tell_callback,
478 		length_callback,
479 		eof_callback,
480 		write_callback,
481 		metadata_callback,
482 		error_callback,
483 		client_data,
484 		/*is_ogg=*/false
485 	);
486 }
487 
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)488 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_ogg_stream(
489 	FLAC__StreamDecoder *decoder,
490 	FLAC__StreamDecoderReadCallback read_callback,
491 	FLAC__StreamDecoderSeekCallback seek_callback,
492 	FLAC__StreamDecoderTellCallback tell_callback,
493 	FLAC__StreamDecoderLengthCallback length_callback,
494 	FLAC__StreamDecoderEofCallback eof_callback,
495 	FLAC__StreamDecoderWriteCallback write_callback,
496 	FLAC__StreamDecoderMetadataCallback metadata_callback,
497 	FLAC__StreamDecoderErrorCallback error_callback,
498 	void *client_data
499 )
500 {
501 	return init_stream_internal_(
502 		decoder,
503 		read_callback,
504 		seek_callback,
505 		tell_callback,
506 		length_callback,
507 		eof_callback,
508 		write_callback,
509 		metadata_callback,
510 		error_callback,
511 		client_data,
512 		/*is_ogg=*/true
513 	);
514 }
515 
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)516 static FLAC__StreamDecoderInitStatus init_FILE_internal_(
517 	FLAC__StreamDecoder *decoder,
518 	FILE *file,
519 	FLAC__StreamDecoderWriteCallback write_callback,
520 	FLAC__StreamDecoderMetadataCallback metadata_callback,
521 	FLAC__StreamDecoderErrorCallback error_callback,
522 	void *client_data,
523 	FLAC__bool is_ogg
524 )
525 {
526 	FLAC__ASSERT(0 != decoder);
527 	FLAC__ASSERT(0 != file);
528 
529 	if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
530 		return decoder->protected_->initstate = FLAC__STREAM_DECODER_INIT_STATUS_ALREADY_INITIALIZED;
531 
532 	if(0 == write_callback || 0 == error_callback)
533 		return decoder->protected_->initstate = FLAC__STREAM_DECODER_INIT_STATUS_INVALID_CALLBACKS;
534 
535 	/*
536 	 * To make sure that our file does not go unclosed after an error, we
537 	 * must assign the FILE pointer before any further error can occur in
538 	 * this routine.
539 	 */
540 	if(file == stdin)
541 		file = get_binary_stdin_(); /* just to be safe */
542 
543 	decoder->private_->file = file;
544 
545 	return init_stream_internal_(
546 		decoder,
547 		file_read_callback_,
548 		decoder->private_->file == stdin? 0: file_seek_callback_,
549 		decoder->private_->file == stdin? 0: file_tell_callback_,
550 		decoder->private_->file == stdin? 0: file_length_callback_,
551 		file_eof_callback_,
552 		write_callback,
553 		metadata_callback,
554 		error_callback,
555 		client_data,
556 		is_ogg
557 	);
558 }
559 
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)560 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_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=*/false);
570 }
571 
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)572 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_ogg_FILE(
573 	FLAC__StreamDecoder *decoder,
574 	FILE *file,
575 	FLAC__StreamDecoderWriteCallback write_callback,
576 	FLAC__StreamDecoderMetadataCallback metadata_callback,
577 	FLAC__StreamDecoderErrorCallback error_callback,
578 	void *client_data
579 )
580 {
581 	return init_FILE_internal_(decoder, file, write_callback, metadata_callback, error_callback, client_data, /*is_ogg=*/true);
582 }
583 
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)584 static FLAC__StreamDecoderInitStatus init_file_internal_(
585 	FLAC__StreamDecoder *decoder,
586 	const char *filename,
587 	FLAC__StreamDecoderWriteCallback write_callback,
588 	FLAC__StreamDecoderMetadataCallback metadata_callback,
589 	FLAC__StreamDecoderErrorCallback error_callback,
590 	void *client_data,
591 	FLAC__bool is_ogg
592 )
593 {
594 	FILE *file;
595 
596 	FLAC__ASSERT(0 != decoder);
597 
598 	/*
599 	 * To make sure that our file does not go unclosed after an error, we
600 	 * have to do the same entrance checks here that are later performed
601 	 * in FLAC__stream_decoder_init_FILE() before the FILE* is assigned.
602 	 */
603 	if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
604 		return decoder->protected_->initstate = FLAC__STREAM_DECODER_INIT_STATUS_ALREADY_INITIALIZED;
605 
606 	if(0 == write_callback || 0 == error_callback)
607 		return decoder->protected_->initstate = FLAC__STREAM_DECODER_INIT_STATUS_INVALID_CALLBACKS;
608 
609 	file = filename? flac_fopen(filename, "rb") : stdin;
610 
611 	if(0 == file)
612 		return FLAC__STREAM_DECODER_INIT_STATUS_ERROR_OPENING_FILE;
613 
614 	return init_FILE_internal_(decoder, file, write_callback, metadata_callback, error_callback, client_data, is_ogg);
615 }
616 
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)617 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_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=*/false);
627 }
628 
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)629 FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_ogg_file(
630 	FLAC__StreamDecoder *decoder,
631 	const char *filename,
632 	FLAC__StreamDecoderWriteCallback write_callback,
633 	FLAC__StreamDecoderMetadataCallback metadata_callback,
634 	FLAC__StreamDecoderErrorCallback error_callback,
635 	void *client_data
636 )
637 {
638 	return init_file_internal_(decoder, filename, write_callback, metadata_callback, error_callback, client_data, /*is_ogg=*/true);
639 }
640 
FLAC__stream_decoder_finish(FLAC__StreamDecoder * decoder)641 FLAC_API FLAC__bool FLAC__stream_decoder_finish(FLAC__StreamDecoder *decoder)
642 {
643 	FLAC__bool md5_failed = false;
644 	unsigned i;
645 
646 	FLAC__ASSERT(0 != decoder);
647 	FLAC__ASSERT(0 != decoder->private_);
648 	FLAC__ASSERT(0 != decoder->protected_);
649 
650 	if(decoder->protected_->state == FLAC__STREAM_DECODER_UNINITIALIZED)
651 		return true;
652 
653 	/* see the comment in FLAC__stream_decoder_reset() as to why we
654 	 * always call FLAC__MD5Final()
655 	 */
656 	FLAC__MD5Final(decoder->private_->computed_md5sum, &decoder->private_->md5context);
657 
658 	if(decoder->private_->has_seek_table && 0 != decoder->private_->seek_table.data.seek_table.points) {
659 		free(decoder->private_->seek_table.data.seek_table.points);
660 		decoder->private_->seek_table.data.seek_table.points = 0;
661 		decoder->private_->has_seek_table = false;
662 	}
663 	FLAC__bitreader_free(decoder->private_->input);
664 	for(i = 0; i < FLAC__MAX_CHANNELS; i++) {
665 		/* WATCHOUT:
666 		 * FLAC__lpc_restore_signal_asm_ia32_mmx() requires that the
667 		 * output arrays have a buffer of up to 3 zeroes in front
668 		 * (at negative indices) for alignment purposes; we use 4
669 		 * to keep the data well-aligned.
670 		 */
671 		if(0 != decoder->private_->output[i]) {
672 			free(decoder->private_->output[i]-4);
673 			decoder->private_->output[i] = 0;
674 		}
675 		if(0 != decoder->private_->residual_unaligned[i]) {
676 			free(decoder->private_->residual_unaligned[i]);
677 			decoder->private_->residual_unaligned[i] = decoder->private_->residual[i] = 0;
678 		}
679 	}
680 	decoder->private_->output_capacity = 0;
681 	decoder->private_->output_channels = 0;
682 
683 #if FLAC__HAS_OGG
684 	if(decoder->private_->is_ogg)
685 		FLAC__ogg_decoder_aspect_finish(&decoder->protected_->ogg_decoder_aspect);
686 #endif
687 
688 	if(0 != decoder->private_->file) {
689 		if(decoder->private_->file != stdin)
690 			fclose(decoder->private_->file);
691 		decoder->private_->file = 0;
692 	}
693 
694 	if(decoder->private_->do_md5_checking) {
695 		if(memcmp(decoder->private_->stream_info.data.stream_info.md5sum, decoder->private_->computed_md5sum, 16))
696 			md5_failed = true;
697 	}
698 	decoder->private_->is_seeking = false;
699 
700 	set_defaults_(decoder);
701 
702 	decoder->protected_->state = FLAC__STREAM_DECODER_UNINITIALIZED;
703 
704 	return !md5_failed;
705 }
706 
FLAC__stream_decoder_set_ogg_serial_number(FLAC__StreamDecoder * decoder,long value)707 FLAC_API FLAC__bool FLAC__stream_decoder_set_ogg_serial_number(FLAC__StreamDecoder *decoder, long value)
708 {
709 	FLAC__ASSERT(0 != decoder);
710 	FLAC__ASSERT(0 != decoder->private_);
711 	FLAC__ASSERT(0 != decoder->protected_);
712 	if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
713 		return false;
714 #if FLAC__HAS_OGG
715 	/* can't check decoder->private_->is_ogg since that's not set until init time */
716 	FLAC__ogg_decoder_aspect_set_serial_number(&decoder->protected_->ogg_decoder_aspect, value);
717 	return true;
718 #else
719 	(void)value;
720 	return false;
721 #endif
722 }
723 
FLAC__stream_decoder_set_md5_checking(FLAC__StreamDecoder * decoder,FLAC__bool value)724 FLAC_API FLAC__bool FLAC__stream_decoder_set_md5_checking(FLAC__StreamDecoder *decoder, FLAC__bool value)
725 {
726 	FLAC__ASSERT(0 != decoder);
727 	FLAC__ASSERT(0 != decoder->protected_);
728 	if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
729 		return false;
730 	decoder->protected_->md5_checking = value;
731 	return true;
732 }
733 
FLAC__stream_decoder_set_metadata_respond(FLAC__StreamDecoder * decoder,FLAC__MetadataType type)734 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond(FLAC__StreamDecoder *decoder, FLAC__MetadataType type)
735 {
736 	FLAC__ASSERT(0 != decoder);
737 	FLAC__ASSERT(0 != decoder->private_);
738 	FLAC__ASSERT(0 != decoder->protected_);
739 	FLAC__ASSERT((unsigned)type <= FLAC__MAX_METADATA_TYPE_CODE);
740 	/* double protection */
741 	if((unsigned)type > FLAC__MAX_METADATA_TYPE_CODE)
742 		return false;
743 	if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
744 		return false;
745 	decoder->private_->metadata_filter[type] = true;
746 	if(type == FLAC__METADATA_TYPE_APPLICATION)
747 		decoder->private_->metadata_filter_ids_count = 0;
748 	return true;
749 }
750 
FLAC__stream_decoder_set_metadata_respond_application(FLAC__StreamDecoder * decoder,const FLAC__byte id[4])751 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond_application(FLAC__StreamDecoder *decoder, const FLAC__byte id[4])
752 {
753 	FLAC__ASSERT(0 != decoder);
754 	FLAC__ASSERT(0 != decoder->private_);
755 	FLAC__ASSERT(0 != decoder->protected_);
756 	FLAC__ASSERT(0 != id);
757 	if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
758 		return false;
759 
760 	if(decoder->private_->metadata_filter[FLAC__METADATA_TYPE_APPLICATION])
761 		return true;
762 
763 	FLAC__ASSERT(0 != decoder->private_->metadata_filter_ids);
764 
765 	if(decoder->private_->metadata_filter_ids_count == decoder->private_->metadata_filter_ids_capacity) {
766 		if(0 == (decoder->private_->metadata_filter_ids = safe_realloc_mul_2op_(decoder->private_->metadata_filter_ids, decoder->private_->metadata_filter_ids_capacity, /*times*/2))) {
767 			decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
768 			return false;
769 		}
770 		decoder->private_->metadata_filter_ids_capacity *= 2;
771 	}
772 
773 	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));
774 	decoder->private_->metadata_filter_ids_count++;
775 
776 	return true;
777 }
778 
FLAC__stream_decoder_set_metadata_respond_all(FLAC__StreamDecoder * decoder)779 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond_all(FLAC__StreamDecoder *decoder)
780 {
781 	unsigned i;
782 	FLAC__ASSERT(0 != decoder);
783 	FLAC__ASSERT(0 != decoder->private_);
784 	FLAC__ASSERT(0 != decoder->protected_);
785 	if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
786 		return false;
787 	for(i = 0; i < sizeof(decoder->private_->metadata_filter) / sizeof(decoder->private_->metadata_filter[0]); i++)
788 		decoder->private_->metadata_filter[i] = true;
789 	decoder->private_->metadata_filter_ids_count = 0;
790 	return true;
791 }
792 
FLAC__stream_decoder_set_metadata_ignore(FLAC__StreamDecoder * decoder,FLAC__MetadataType type)793 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore(FLAC__StreamDecoder *decoder, FLAC__MetadataType type)
794 {
795 	FLAC__ASSERT(0 != decoder);
796 	FLAC__ASSERT(0 != decoder->private_);
797 	FLAC__ASSERT(0 != decoder->protected_);
798 	FLAC__ASSERT((unsigned)type <= FLAC__MAX_METADATA_TYPE_CODE);
799 	/* double protection */
800 	if((unsigned)type > FLAC__MAX_METADATA_TYPE_CODE)
801 		return false;
802 	if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
803 		return false;
804 	decoder->private_->metadata_filter[type] = false;
805 	if(type == FLAC__METADATA_TYPE_APPLICATION)
806 		decoder->private_->metadata_filter_ids_count = 0;
807 	return true;
808 }
809 
FLAC__stream_decoder_set_metadata_ignore_application(FLAC__StreamDecoder * decoder,const FLAC__byte id[4])810 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore_application(FLAC__StreamDecoder *decoder, const FLAC__byte id[4])
811 {
812 	FLAC__ASSERT(0 != decoder);
813 	FLAC__ASSERT(0 != decoder->private_);
814 	FLAC__ASSERT(0 != decoder->protected_);
815 	FLAC__ASSERT(0 != id);
816 	if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
817 		return false;
818 
819 	if(!decoder->private_->metadata_filter[FLAC__METADATA_TYPE_APPLICATION])
820 		return true;
821 
822 	FLAC__ASSERT(0 != decoder->private_->metadata_filter_ids);
823 
824 	if(decoder->private_->metadata_filter_ids_count == decoder->private_->metadata_filter_ids_capacity) {
825 		if(0 == (decoder->private_->metadata_filter_ids = safe_realloc_mul_2op_(decoder->private_->metadata_filter_ids, decoder->private_->metadata_filter_ids_capacity, /*times*/2))) {
826 			decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
827 			return false;
828 		}
829 		decoder->private_->metadata_filter_ids_capacity *= 2;
830 	}
831 
832 	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));
833 	decoder->private_->metadata_filter_ids_count++;
834 
835 	return true;
836 }
837 
FLAC__stream_decoder_set_metadata_ignore_all(FLAC__StreamDecoder * decoder)838 FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore_all(FLAC__StreamDecoder *decoder)
839 {
840 	FLAC__ASSERT(0 != decoder);
841 	FLAC__ASSERT(0 != decoder->private_);
842 	FLAC__ASSERT(0 != decoder->protected_);
843 	if(decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
844 		return false;
845 	memset(decoder->private_->metadata_filter, 0, sizeof(decoder->private_->metadata_filter));
846 	decoder->private_->metadata_filter_ids_count = 0;
847 	return true;
848 }
849 
FLAC__stream_decoder_get_state(const FLAC__StreamDecoder * decoder)850 FLAC_API FLAC__StreamDecoderState FLAC__stream_decoder_get_state(const FLAC__StreamDecoder *decoder)
851 {
852 	FLAC__ASSERT(0 != decoder);
853 	FLAC__ASSERT(0 != decoder->protected_);
854 	return decoder->protected_->state;
855 }
856 
FLAC__stream_decoder_get_resolved_state_string(const FLAC__StreamDecoder * decoder)857 FLAC_API const char *FLAC__stream_decoder_get_resolved_state_string(const FLAC__StreamDecoder *decoder)
858 {
859 	return FLAC__StreamDecoderStateString[decoder->protected_->state];
860 }
861 
FLAC__stream_decoder_get_md5_checking(const FLAC__StreamDecoder * decoder)862 FLAC_API FLAC__bool FLAC__stream_decoder_get_md5_checking(const FLAC__StreamDecoder *decoder)
863 {
864 	FLAC__ASSERT(0 != decoder);
865 	FLAC__ASSERT(0 != decoder->protected_);
866 	return decoder->protected_->md5_checking;
867 }
868 
FLAC__stream_decoder_get_total_samples(const FLAC__StreamDecoder * decoder)869 FLAC_API FLAC__uint64 FLAC__stream_decoder_get_total_samples(const FLAC__StreamDecoder *decoder)
870 {
871 	FLAC__ASSERT(0 != decoder);
872 	FLAC__ASSERT(0 != decoder->protected_);
873 	return decoder->private_->has_stream_info? decoder->private_->stream_info.data.stream_info.total_samples : 0;
874 }
875 
FLAC__stream_decoder_get_channels(const FLAC__StreamDecoder * decoder)876 FLAC_API unsigned FLAC__stream_decoder_get_channels(const FLAC__StreamDecoder *decoder)
877 {
878 	FLAC__ASSERT(0 != decoder);
879 	FLAC__ASSERT(0 != decoder->protected_);
880 	return decoder->protected_->channels;
881 }
882 
FLAC__stream_decoder_get_channel_assignment(const FLAC__StreamDecoder * decoder)883 FLAC_API FLAC__ChannelAssignment FLAC__stream_decoder_get_channel_assignment(const FLAC__StreamDecoder *decoder)
884 {
885 	FLAC__ASSERT(0 != decoder);
886 	FLAC__ASSERT(0 != decoder->protected_);
887 	return decoder->protected_->channel_assignment;
888 }
889 
FLAC__stream_decoder_get_bits_per_sample(const FLAC__StreamDecoder * decoder)890 FLAC_API unsigned FLAC__stream_decoder_get_bits_per_sample(const FLAC__StreamDecoder *decoder)
891 {
892 	FLAC__ASSERT(0 != decoder);
893 	FLAC__ASSERT(0 != decoder->protected_);
894 	return decoder->protected_->bits_per_sample;
895 }
896 
FLAC__stream_decoder_get_sample_rate(const FLAC__StreamDecoder * decoder)897 FLAC_API unsigned FLAC__stream_decoder_get_sample_rate(const FLAC__StreamDecoder *decoder)
898 {
899 	FLAC__ASSERT(0 != decoder);
900 	FLAC__ASSERT(0 != decoder->protected_);
901 	return decoder->protected_->sample_rate;
902 }
903 
FLAC__stream_decoder_get_blocksize(const FLAC__StreamDecoder * decoder)904 FLAC_API unsigned FLAC__stream_decoder_get_blocksize(const FLAC__StreamDecoder *decoder)
905 {
906 	FLAC__ASSERT(0 != decoder);
907 	FLAC__ASSERT(0 != decoder->protected_);
908 	return decoder->protected_->blocksize;
909 }
910 
FLAC__stream_decoder_get_decode_position(const FLAC__StreamDecoder * decoder,FLAC__uint64 * position)911 FLAC_API FLAC__bool FLAC__stream_decoder_get_decode_position(const FLAC__StreamDecoder *decoder, FLAC__uint64 *position)
912 {
913 	FLAC__ASSERT(0 != decoder);
914 	FLAC__ASSERT(0 != decoder->private_);
915 	FLAC__ASSERT(0 != position);
916 
917 #if FLAC__HAS_OGG
918 	if(decoder->private_->is_ogg)
919 		return false;
920 #endif
921 	if(0 == decoder->private_->tell_callback)
922 		return false;
923 	if(decoder->private_->tell_callback(decoder, position, decoder->private_->client_data) != FLAC__STREAM_DECODER_TELL_STATUS_OK)
924 		return false;
925 	/* should never happen since all FLAC frames and metadata blocks are byte aligned, but check just in case */
926 	if(!FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input))
927 		return false;
928 	FLAC__ASSERT(*position >= FLAC__stream_decoder_get_input_bytes_unconsumed(decoder));
929 	*position -= FLAC__stream_decoder_get_input_bytes_unconsumed(decoder);
930 	return true;
931 }
932 
FLAC__stream_decoder_flush(FLAC__StreamDecoder * decoder)933 FLAC_API FLAC__bool FLAC__stream_decoder_flush(FLAC__StreamDecoder *decoder)
934 {
935 	FLAC__ASSERT(0 != decoder);
936 	FLAC__ASSERT(0 != decoder->private_);
937 	FLAC__ASSERT(0 != decoder->protected_);
938 
939 	if(!decoder->private_->internal_reset_hack && decoder->protected_->state == FLAC__STREAM_DECODER_UNINITIALIZED)
940 		return false;
941 
942 	decoder->private_->samples_decoded = 0;
943 	decoder->private_->do_md5_checking = false;
944 
945 #if FLAC__HAS_OGG
946 	if(decoder->private_->is_ogg)
947 		FLAC__ogg_decoder_aspect_flush(&decoder->protected_->ogg_decoder_aspect);
948 #endif
949 
950 	if(!FLAC__bitreader_clear(decoder->private_->input)) {
951 		decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
952 		return false;
953 	}
954 	decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
955 
956 	return true;
957 }
958 
FLAC__stream_decoder_reset(FLAC__StreamDecoder * decoder)959 FLAC_API FLAC__bool FLAC__stream_decoder_reset(FLAC__StreamDecoder *decoder)
960 {
961 	FLAC__ASSERT(0 != decoder);
962 	FLAC__ASSERT(0 != decoder->private_);
963 	FLAC__ASSERT(0 != decoder->protected_);
964 
965 	if(!FLAC__stream_decoder_flush(decoder)) {
966 		/* above call sets the state for us */
967 		return false;
968 	}
969 
970 #if FLAC__HAS_OGG
971 	/*@@@ could go in !internal_reset_hack block below */
972 	if(decoder->private_->is_ogg)
973 		FLAC__ogg_decoder_aspect_reset(&decoder->protected_->ogg_decoder_aspect);
974 #endif
975 
976 	/* Rewind if necessary.  If FLAC__stream_decoder_init() is calling us,
977 	 * (internal_reset_hack) don't try to rewind since we are already at
978 	 * the beginning of the stream and don't want to fail if the input is
979 	 * not seekable.
980 	 */
981 	if(!decoder->private_->internal_reset_hack) {
982 		if(decoder->private_->file == stdin)
983 			return false; /* can't rewind stdin, reset fails */
984 		if(decoder->private_->seek_callback && decoder->private_->seek_callback(decoder, 0, decoder->private_->client_data) == FLAC__STREAM_DECODER_SEEK_STATUS_ERROR)
985 			return false; /* seekable and seek fails, reset fails */
986 	}
987 	else
988 		decoder->private_->internal_reset_hack = false;
989 
990 	decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_METADATA;
991 
992 	decoder->private_->has_stream_info = false;
993 	if(decoder->private_->has_seek_table && 0 != decoder->private_->seek_table.data.seek_table.points) {
994 		free(decoder->private_->seek_table.data.seek_table.points);
995 		decoder->private_->seek_table.data.seek_table.points = 0;
996 		decoder->private_->has_seek_table = false;
997 	}
998 	decoder->private_->do_md5_checking = decoder->protected_->md5_checking;
999 	/*
1000 	 * This goes in reset() and not flush() because according to the spec, a
1001 	 * fixed-blocksize stream must stay that way through the whole stream.
1002 	 */
1003 	decoder->private_->fixed_block_size = decoder->private_->next_fixed_block_size = 0;
1004 
1005 	/* We initialize the FLAC__MD5Context even though we may never use it.  This
1006 	 * is because md5 checking may be turned on to start and then turned off if
1007 	 * a seek occurs.  So we init the context here and finalize it in
1008 	 * FLAC__stream_decoder_finish() to make sure things are always cleaned up
1009 	 * properly.
1010 	 */
1011 	FLAC__MD5Init(&decoder->private_->md5context);
1012 
1013 	decoder->private_->first_frame_offset = 0;
1014 	decoder->private_->unparseable_frame_count = 0;
1015 
1016 	return true;
1017 }
1018 
FLAC__stream_decoder_process_single(FLAC__StreamDecoder * decoder)1019 FLAC_API FLAC__bool FLAC__stream_decoder_process_single(FLAC__StreamDecoder *decoder)
1020 {
1021 	FLAC__bool got_a_frame;
1022 	FLAC__ASSERT(0 != decoder);
1023 	FLAC__ASSERT(0 != decoder->protected_);
1024 
1025 	while(1) {
1026 		switch(decoder->protected_->state) {
1027 			case FLAC__STREAM_DECODER_SEARCH_FOR_METADATA:
1028 				if(!find_metadata_(decoder))
1029 					return false; /* above function sets the status for us */
1030 				break;
1031 			case FLAC__STREAM_DECODER_READ_METADATA:
1032 				if(!read_metadata_(decoder))
1033 					return false; /* above function sets the status for us */
1034 				else
1035 					return true;
1036 			case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
1037 				if(!frame_sync_(decoder))
1038 					return true; /* above function sets the status for us */
1039 				break;
1040 			case FLAC__STREAM_DECODER_READ_FRAME:
1041 				if(!read_frame_(decoder, &got_a_frame, /*do_full_decode=*/true))
1042 					return false; /* above function sets the status for us */
1043 				if(got_a_frame)
1044 					return true; /* above function sets the status for us */
1045 				break;
1046 			case FLAC__STREAM_DECODER_END_OF_STREAM:
1047 			case FLAC__STREAM_DECODER_ABORTED:
1048 				return true;
1049 			default:
1050 				FLAC__ASSERT(0);
1051 				return false;
1052 		}
1053 	}
1054 }
1055 
FLAC__stream_decoder_process_until_end_of_metadata(FLAC__StreamDecoder * decoder)1056 FLAC_API FLAC__bool FLAC__stream_decoder_process_until_end_of_metadata(FLAC__StreamDecoder *decoder)
1057 {
1058 	FLAC__ASSERT(0 != decoder);
1059 	FLAC__ASSERT(0 != decoder->protected_);
1060 
1061 	while(1) {
1062 		switch(decoder->protected_->state) {
1063 			case FLAC__STREAM_DECODER_SEARCH_FOR_METADATA:
1064 				if(!find_metadata_(decoder))
1065 					return false; /* above function sets the status for us */
1066 				break;
1067 			case FLAC__STREAM_DECODER_READ_METADATA:
1068 				if(!read_metadata_(decoder))
1069 					return false; /* above function sets the status for us */
1070 				break;
1071 			case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
1072 			case FLAC__STREAM_DECODER_READ_FRAME:
1073 			case FLAC__STREAM_DECODER_END_OF_STREAM:
1074 			case FLAC__STREAM_DECODER_ABORTED:
1075 				return true;
1076 			default:
1077 				FLAC__ASSERT(0);
1078 				return false;
1079 		}
1080 	}
1081 }
1082 
FLAC__stream_decoder_process_until_end_of_stream(FLAC__StreamDecoder * decoder)1083 FLAC_API FLAC__bool FLAC__stream_decoder_process_until_end_of_stream(FLAC__StreamDecoder *decoder)
1084 {
1085 	FLAC__bool dummy;
1086 	FLAC__ASSERT(0 != decoder);
1087 	FLAC__ASSERT(0 != decoder->protected_);
1088 
1089 	while(1) {
1090 		switch(decoder->protected_->state) {
1091 			case FLAC__STREAM_DECODER_SEARCH_FOR_METADATA:
1092 				if(!find_metadata_(decoder))
1093 					return false; /* above function sets the status for us */
1094 				break;
1095 			case FLAC__STREAM_DECODER_READ_METADATA:
1096 				if(!read_metadata_(decoder))
1097 					return false; /* above function sets the status for us */
1098 				break;
1099 			case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
1100 				if(!frame_sync_(decoder))
1101 					return true; /* above function sets the status for us */
1102 				break;
1103 			case FLAC__STREAM_DECODER_READ_FRAME:
1104 				if(!read_frame_(decoder, &dummy, /*do_full_decode=*/true))
1105 					return false; /* above function sets the status for us */
1106 				break;
1107 			case FLAC__STREAM_DECODER_END_OF_STREAM:
1108 			case FLAC__STREAM_DECODER_ABORTED:
1109 				return true;
1110 			default:
1111 				FLAC__ASSERT(0);
1112 				return false;
1113 		}
1114 	}
1115 }
1116 
FLAC__stream_decoder_skip_single_frame(FLAC__StreamDecoder * decoder)1117 FLAC_API FLAC__bool FLAC__stream_decoder_skip_single_frame(FLAC__StreamDecoder *decoder)
1118 {
1119 	FLAC__bool got_a_frame;
1120 	FLAC__ASSERT(0 != decoder);
1121 	FLAC__ASSERT(0 != decoder->protected_);
1122 
1123 	while(1) {
1124 		switch(decoder->protected_->state) {
1125 			case FLAC__STREAM_DECODER_SEARCH_FOR_METADATA:
1126 			case FLAC__STREAM_DECODER_READ_METADATA:
1127 				return false; /* above function sets the status for us */
1128 			case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
1129 				if(!frame_sync_(decoder))
1130 					return true; /* above function sets the status for us */
1131 				break;
1132 			case FLAC__STREAM_DECODER_READ_FRAME:
1133 				if(!read_frame_(decoder, &got_a_frame, /*do_full_decode=*/false))
1134 					return false; /* above function sets the status for us */
1135 				if(got_a_frame)
1136 					return true; /* above function sets the status for us */
1137 				break;
1138 			case FLAC__STREAM_DECODER_END_OF_STREAM:
1139 			case FLAC__STREAM_DECODER_ABORTED:
1140 				return true;
1141 			default:
1142 				FLAC__ASSERT(0);
1143 				return false;
1144 		}
1145 	}
1146 }
1147 
FLAC__stream_decoder_seek_absolute(FLAC__StreamDecoder * decoder,FLAC__uint64 sample)1148 FLAC_API FLAC__bool FLAC__stream_decoder_seek_absolute(FLAC__StreamDecoder *decoder, FLAC__uint64 sample)
1149 {
1150 	FLAC__uint64 length;
1151 
1152 	FLAC__ASSERT(0 != decoder);
1153 
1154 	if(
1155 		decoder->protected_->state != FLAC__STREAM_DECODER_SEARCH_FOR_METADATA &&
1156 		decoder->protected_->state != FLAC__STREAM_DECODER_READ_METADATA &&
1157 		decoder->protected_->state != FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC &&
1158 		decoder->protected_->state != FLAC__STREAM_DECODER_READ_FRAME &&
1159 		decoder->protected_->state != FLAC__STREAM_DECODER_END_OF_STREAM
1160 	)
1161 		return false;
1162 
1163 	if(0 == decoder->private_->seek_callback)
1164 		return false;
1165 
1166 	FLAC__ASSERT(decoder->private_->seek_callback);
1167 	FLAC__ASSERT(decoder->private_->tell_callback);
1168 	FLAC__ASSERT(decoder->private_->length_callback);
1169 	FLAC__ASSERT(decoder->private_->eof_callback);
1170 
1171 	if(FLAC__stream_decoder_get_total_samples(decoder) > 0 && sample >= FLAC__stream_decoder_get_total_samples(decoder))
1172 		return false;
1173 
1174 	decoder->private_->is_seeking = true;
1175 
1176 	/* turn off md5 checking if a seek is attempted */
1177 	decoder->private_->do_md5_checking = false;
1178 
1179 	/* 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) */
1180 	if(decoder->private_->length_callback(decoder, &length, decoder->private_->client_data) != FLAC__STREAM_DECODER_LENGTH_STATUS_OK) {
1181 		decoder->private_->is_seeking = false;
1182 		return false;
1183 	}
1184 
1185 	/* if we haven't finished processing the metadata yet, do that so we have the STREAMINFO, SEEK_TABLE, and first_frame_offset */
1186 	if(
1187 		decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_METADATA ||
1188 		decoder->protected_->state == FLAC__STREAM_DECODER_READ_METADATA
1189 	) {
1190 		if(!FLAC__stream_decoder_process_until_end_of_metadata(decoder)) {
1191 			/* above call sets the state for us */
1192 			decoder->private_->is_seeking = false;
1193 			return false;
1194 		}
1195 		/* check this again in case we didn't know total_samples the first time */
1196 		if(FLAC__stream_decoder_get_total_samples(decoder) > 0 && sample >= FLAC__stream_decoder_get_total_samples(decoder)) {
1197 			decoder->private_->is_seeking = false;
1198 			return false;
1199 		}
1200 	}
1201 
1202 	{
1203 		const FLAC__bool ok =
1204 #if FLAC__HAS_OGG
1205 			decoder->private_->is_ogg?
1206 			seek_to_absolute_sample_ogg_(decoder, length, sample) :
1207 #endif
1208 			seek_to_absolute_sample_(decoder, length, sample)
1209 		;
1210 		decoder->private_->is_seeking = false;
1211 		return ok;
1212 	}
1213 }
1214 
1215 /***********************************************************************
1216  *
1217  * Protected class methods
1218  *
1219  ***********************************************************************/
1220 
FLAC__stream_decoder_get_input_bytes_unconsumed(const FLAC__StreamDecoder * decoder)1221 unsigned FLAC__stream_decoder_get_input_bytes_unconsumed(const FLAC__StreamDecoder *decoder)
1222 {
1223 	FLAC__ASSERT(0 != decoder);
1224 	FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1225 	FLAC__ASSERT(!(FLAC__bitreader_get_input_bits_unconsumed(decoder->private_->input) & 7));
1226 	return FLAC__bitreader_get_input_bits_unconsumed(decoder->private_->input) / 8;
1227 }
1228 
1229 /***********************************************************************
1230  *
1231  * Private class methods
1232  *
1233  ***********************************************************************/
1234 
set_defaults_(FLAC__StreamDecoder * decoder)1235 void set_defaults_(FLAC__StreamDecoder *decoder)
1236 {
1237 #if FLAC__HAS_OGG
1238 	decoder->private_->is_ogg = false;
1239 #endif
1240 	decoder->private_->read_callback = 0;
1241 	decoder->private_->seek_callback = 0;
1242 	decoder->private_->tell_callback = 0;
1243 	decoder->private_->length_callback = 0;
1244 	decoder->private_->eof_callback = 0;
1245 	decoder->private_->write_callback = 0;
1246 	decoder->private_->metadata_callback = 0;
1247 	decoder->private_->error_callback = 0;
1248 	decoder->private_->client_data = 0;
1249 
1250 	memset(decoder->private_->metadata_filter, 0, sizeof(decoder->private_->metadata_filter));
1251 	decoder->private_->metadata_filter[FLAC__METADATA_TYPE_STREAMINFO] = true;
1252 	decoder->private_->metadata_filter_ids_count = 0;
1253 
1254 	decoder->protected_->md5_checking = false;
1255 
1256 #if FLAC__HAS_OGG
1257 	FLAC__ogg_decoder_aspect_set_defaults(&decoder->protected_->ogg_decoder_aspect);
1258 #endif
1259 }
1260 
1261 /*
1262  * This will forcibly set stdin to binary mode (for OSes that require it)
1263  */
get_binary_stdin_(void)1264 FILE *get_binary_stdin_(void)
1265 {
1266 	/* if something breaks here it is probably due to the presence or
1267 	 * absence of an underscore before the identifiers 'setmode',
1268 	 * 'fileno', and/or 'O_BINARY'; check your system header files.
1269 	 */
1270 #if defined _MSC_VER || defined __MINGW32__
1271 	_setmode(_fileno(stdin), _O_BINARY);
1272 #elif defined __CYGWIN__
1273 	/* almost certainly not needed for any modern Cygwin, but let's be safe... */
1274 	setmode(_fileno(stdin), _O_BINARY);
1275 #elif defined __EMX__
1276 	setmode(fileno(stdin), O_BINARY);
1277 #endif
1278 
1279 	return stdin;
1280 }
1281 
allocate_output_(FLAC__StreamDecoder * decoder,unsigned size,unsigned channels)1282 FLAC__bool allocate_output_(FLAC__StreamDecoder *decoder, unsigned size, unsigned channels)
1283 {
1284 	unsigned i;
1285 	FLAC__int32 *tmp;
1286 
1287 	if(size <= decoder->private_->output_capacity && channels <= decoder->private_->output_channels)
1288 		return true;
1289 
1290 	/* simply using realloc() is not practical because the number of channels may change mid-stream */
1291 
1292 	for(i = 0; i < FLAC__MAX_CHANNELS; i++) {
1293 		if(0 != decoder->private_->output[i]) {
1294 			free(decoder->private_->output[i]-4);
1295 			decoder->private_->output[i] = 0;
1296 		}
1297 		if(0 != decoder->private_->residual_unaligned[i]) {
1298 			free(decoder->private_->residual_unaligned[i]);
1299 			decoder->private_->residual_unaligned[i] = decoder->private_->residual[i] = 0;
1300 		}
1301 	}
1302 
1303 	for(i = 0; i < channels; i++) {
1304 		/* WATCHOUT:
1305 		 * FLAC__lpc_restore_signal_asm_ia32_mmx() requires that the
1306 		 * output arrays have a buffer of up to 3 zeroes in front
1307 		 * (at negative indices) for alignment purposes; we use 4
1308 		 * to keep the data well-aligned.
1309 		 */
1310 		tmp = safe_malloc_muladd2_(sizeof(FLAC__int32), /*times (*/size, /*+*/4/*)*/);
1311 		if(tmp == 0) {
1312 			decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1313 			return false;
1314 		}
1315 		memset(tmp, 0, sizeof(FLAC__int32)*4);
1316 		decoder->private_->output[i] = tmp + 4;
1317 
1318 		if(!FLAC__memory_alloc_aligned_int32_array(size, &decoder->private_->residual_unaligned[i], &decoder->private_->residual[i])) {
1319 			decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1320 			return false;
1321 		}
1322 	}
1323 
1324 	decoder->private_->output_capacity = size;
1325 	decoder->private_->output_channels = channels;
1326 
1327 	return true;
1328 }
1329 
has_id_filtered_(FLAC__StreamDecoder * decoder,FLAC__byte * id)1330 FLAC__bool has_id_filtered_(FLAC__StreamDecoder *decoder, FLAC__byte *id)
1331 {
1332 	size_t i;
1333 
1334 	FLAC__ASSERT(0 != decoder);
1335 	FLAC__ASSERT(0 != decoder->private_);
1336 
1337 	for(i = 0; i < decoder->private_->metadata_filter_ids_count; i++)
1338 		if(0 == memcmp(decoder->private_->metadata_filter_ids + i * (FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8), id, (FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8)))
1339 			return true;
1340 
1341 	return false;
1342 }
1343 
find_metadata_(FLAC__StreamDecoder * decoder)1344 FLAC__bool find_metadata_(FLAC__StreamDecoder *decoder)
1345 {
1346 	FLAC__uint32 x;
1347 	unsigned i, id;
1348 	FLAC__bool first = true;
1349 
1350 	FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1351 
1352 	for(i = id = 0; i < 4; ) {
1353 		if(decoder->private_->cached) {
1354 			x = (FLAC__uint32)decoder->private_->lookahead;
1355 			decoder->private_->cached = false;
1356 		}
1357 		else {
1358 			if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
1359 				return false; /* read_callback_ sets the state for us */
1360 		}
1361 		if(x == FLAC__STREAM_SYNC_STRING[i]) {
1362 			first = true;
1363 			i++;
1364 			id = 0;
1365 			continue;
1366 		}
1367 
1368 		if(id >= 3)
1369 			return false;
1370 
1371 		if(x == ID3V2_TAG_[id]) {
1372 			id++;
1373 			i = 0;
1374 			if(id == 3) {
1375 				if(!skip_id3v2_tag_(decoder))
1376 					return false; /* skip_id3v2_tag_ sets the state for us */
1377 			}
1378 			continue;
1379 		}
1380 		id = 0;
1381 		if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
1382 			decoder->private_->header_warmup[0] = (FLAC__byte)x;
1383 			if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
1384 				return false; /* read_callback_ sets the state for us */
1385 
1386 			/* 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 */
1387 			/* else we have to check if the second byte is the end of a sync code */
1388 			if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
1389 				decoder->private_->lookahead = (FLAC__byte)x;
1390 				decoder->private_->cached = true;
1391 			}
1392 			else if(x >> 1 == 0x7c) { /* MAGIC NUMBER for the last 6 sync bits and reserved 7th bit */
1393 				decoder->private_->header_warmup[1] = (FLAC__byte)x;
1394 				decoder->protected_->state = FLAC__STREAM_DECODER_READ_FRAME;
1395 				return true;
1396 			}
1397 		}
1398 		i = 0;
1399 		if(first) {
1400 			send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
1401 			first = false;
1402 		}
1403 	}
1404 
1405 	decoder->protected_->state = FLAC__STREAM_DECODER_READ_METADATA;
1406 	return true;
1407 }
1408 
read_metadata_(FLAC__StreamDecoder * decoder)1409 FLAC__bool read_metadata_(FLAC__StreamDecoder *decoder)
1410 {
1411 	FLAC__bool is_last;
1412 	FLAC__uint32 i, x, type, length;
1413 
1414 	FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1415 
1416 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_IS_LAST_LEN))
1417 		return false; /* read_callback_ sets the state for us */
1418 	is_last = x? true : false;
1419 
1420 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &type, FLAC__STREAM_METADATA_TYPE_LEN))
1421 		return false; /* read_callback_ sets the state for us */
1422 
1423 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &length, FLAC__STREAM_METADATA_LENGTH_LEN))
1424 		return false; /* read_callback_ sets the state for us */
1425 
1426 	if(type == FLAC__METADATA_TYPE_STREAMINFO) {
1427 		if(!read_metadata_streaminfo_(decoder, is_last, length))
1428 			return false;
1429 
1430 		decoder->private_->has_stream_info = true;
1431 		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))
1432 			decoder->private_->do_md5_checking = false;
1433 		if(!decoder->private_->is_seeking && decoder->private_->metadata_filter[FLAC__METADATA_TYPE_STREAMINFO] && decoder->private_->metadata_callback)
1434 			decoder->private_->metadata_callback(decoder, &decoder->private_->stream_info, decoder->private_->client_data);
1435 	}
1436 	else if(type == FLAC__METADATA_TYPE_SEEKTABLE) {
1437 		if(!read_metadata_seektable_(decoder, is_last, length))
1438 			return false;
1439 
1440 		decoder->private_->has_seek_table = true;
1441 		if(!decoder->private_->is_seeking && decoder->private_->metadata_filter[FLAC__METADATA_TYPE_SEEKTABLE] && decoder->private_->metadata_callback)
1442 			decoder->private_->metadata_callback(decoder, &decoder->private_->seek_table, decoder->private_->client_data);
1443 	}
1444 	else {
1445 		FLAC__bool skip_it = !decoder->private_->metadata_filter[type];
1446 		unsigned real_length = length;
1447 		FLAC__StreamMetadata block;
1448 
1449 		memset(&block, 0, sizeof(block));
1450 		block.is_last = is_last;
1451 		block.type = (FLAC__MetadataType)type;
1452 		block.length = length;
1453 
1454 		if(type == FLAC__METADATA_TYPE_APPLICATION) {
1455 			if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, block.data.application.id, FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8))
1456 				return false; /* read_callback_ sets the state for us */
1457 
1458 			if(real_length < FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8) { /* underflow check */
1459 				decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;/*@@@@@@ maybe wrong error? need to resync?*/
1460 				return false;
1461 			}
1462 
1463 			real_length -= FLAC__STREAM_METADATA_APPLICATION_ID_LEN/8;
1464 
1465 			if(decoder->private_->metadata_filter_ids_count > 0 && has_id_filtered_(decoder, block.data.application.id))
1466 				skip_it = !skip_it;
1467 		}
1468 
1469 		if(skip_it) {
1470 			if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, real_length))
1471 				return false; /* read_callback_ sets the state for us */
1472 		}
1473 		else {
1474 			FLAC__bool ok = true;
1475 			switch(type) {
1476 				case FLAC__METADATA_TYPE_PADDING:
1477 					/* skip the padding bytes */
1478 					if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, real_length))
1479 						ok = false; /* read_callback_ sets the state for us */
1480 					break;
1481 				case FLAC__METADATA_TYPE_APPLICATION:
1482 					/* remember, we read the ID already */
1483 					if(real_length > 0) {
1484 						if(0 == (block.data.application.data = malloc(real_length))) {
1485 							decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1486 							ok = false;
1487 						}
1488 						else if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, block.data.application.data, real_length))
1489 							ok = false; /* read_callback_ sets the state for us */
1490 					}
1491 					else
1492 						block.data.application.data = 0;
1493 					break;
1494 				case FLAC__METADATA_TYPE_VORBIS_COMMENT:
1495 					if(!read_metadata_vorbiscomment_(decoder, &block.data.vorbis_comment, real_length))
1496 						ok = false;
1497 					break;
1498 				case FLAC__METADATA_TYPE_CUESHEET:
1499 					if(!read_metadata_cuesheet_(decoder, &block.data.cue_sheet))
1500 						ok = false;
1501 					break;
1502 				case FLAC__METADATA_TYPE_PICTURE:
1503 					if(!read_metadata_picture_(decoder, &block.data.picture))
1504 						ok = false;
1505 					break;
1506 				case FLAC__METADATA_TYPE_STREAMINFO:
1507 				case FLAC__METADATA_TYPE_SEEKTABLE:
1508 					FLAC__ASSERT(0);
1509 					break;
1510 				default:
1511 					if(real_length > 0) {
1512 						if(0 == (block.data.unknown.data = malloc(real_length))) {
1513 							decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1514 							ok = false;
1515 						}
1516 						else if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, block.data.unknown.data, real_length))
1517 							ok = false; /* read_callback_ sets the state for us */
1518 					}
1519 					else
1520 						block.data.unknown.data = 0;
1521 					break;
1522 			}
1523 			if(ok && !decoder->private_->is_seeking && decoder->private_->metadata_callback)
1524 				decoder->private_->metadata_callback(decoder, &block, decoder->private_->client_data);
1525 
1526 			/* now we have to free any malloc()ed data in the block */
1527 			switch(type) {
1528 				case FLAC__METADATA_TYPE_PADDING:
1529 					break;
1530 				case FLAC__METADATA_TYPE_APPLICATION:
1531 					if(0 != block.data.application.data)
1532 						free(block.data.application.data);
1533 					break;
1534 				case FLAC__METADATA_TYPE_VORBIS_COMMENT:
1535 					if(0 != block.data.vorbis_comment.vendor_string.entry)
1536 						free(block.data.vorbis_comment.vendor_string.entry);
1537 					if(block.data.vorbis_comment.num_comments > 0)
1538 						for(i = 0; i < block.data.vorbis_comment.num_comments; i++)
1539 							if(0 != block.data.vorbis_comment.comments[i].entry)
1540 								free(block.data.vorbis_comment.comments[i].entry);
1541 					if(0 != block.data.vorbis_comment.comments)
1542 						free(block.data.vorbis_comment.comments);
1543 					break;
1544 				case FLAC__METADATA_TYPE_CUESHEET:
1545 					if(block.data.cue_sheet.num_tracks > 0)
1546 						for(i = 0; i < block.data.cue_sheet.num_tracks; i++)
1547 							if(0 != block.data.cue_sheet.tracks[i].indices)
1548 								free(block.data.cue_sheet.tracks[i].indices);
1549 					if(0 != block.data.cue_sheet.tracks)
1550 						free(block.data.cue_sheet.tracks);
1551 					break;
1552 				case FLAC__METADATA_TYPE_PICTURE:
1553 					if(0 != block.data.picture.mime_type)
1554 						free(block.data.picture.mime_type);
1555 					if(0 != block.data.picture.description)
1556 						free(block.data.picture.description);
1557 					if(0 != block.data.picture.data)
1558 						free(block.data.picture.data);
1559 					break;
1560 				case FLAC__METADATA_TYPE_STREAMINFO:
1561 				case FLAC__METADATA_TYPE_SEEKTABLE:
1562 					FLAC__ASSERT(0);
1563 				default:
1564 					if(0 != block.data.unknown.data)
1565 						free(block.data.unknown.data);
1566 					break;
1567 			}
1568 
1569 			if(!ok) /* anything that unsets "ok" should also make sure decoder->protected_->state is updated */
1570 				return false;
1571 		}
1572 	}
1573 
1574 	if(is_last) {
1575 		/* if this fails, it's OK, it's just a hint for the seek routine */
1576 		if(!FLAC__stream_decoder_get_decode_position(decoder, &decoder->private_->first_frame_offset))
1577 			decoder->private_->first_frame_offset = 0;
1578 		decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
1579 	}
1580 
1581 	return true;
1582 }
1583 
read_metadata_streaminfo_(FLAC__StreamDecoder * decoder,FLAC__bool is_last,unsigned length)1584 FLAC__bool read_metadata_streaminfo_(FLAC__StreamDecoder *decoder, FLAC__bool is_last, unsigned length)
1585 {
1586 	FLAC__uint32 x;
1587 	unsigned bits, used_bits = 0;
1588 
1589 	FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1590 
1591 	decoder->private_->stream_info.type = FLAC__METADATA_TYPE_STREAMINFO;
1592 	decoder->private_->stream_info.is_last = is_last;
1593 	decoder->private_->stream_info.length = length;
1594 
1595 	bits = FLAC__STREAM_METADATA_STREAMINFO_MIN_BLOCK_SIZE_LEN;
1596 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, bits))
1597 		return false; /* read_callback_ sets the state for us */
1598 	decoder->private_->stream_info.data.stream_info.min_blocksize = x;
1599 	used_bits += bits;
1600 
1601 	bits = FLAC__STREAM_METADATA_STREAMINFO_MAX_BLOCK_SIZE_LEN;
1602 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_MAX_BLOCK_SIZE_LEN))
1603 		return false; /* read_callback_ sets the state for us */
1604 	decoder->private_->stream_info.data.stream_info.max_blocksize = x;
1605 	used_bits += bits;
1606 
1607 	bits = FLAC__STREAM_METADATA_STREAMINFO_MIN_FRAME_SIZE_LEN;
1608 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_MIN_FRAME_SIZE_LEN))
1609 		return false; /* read_callback_ sets the state for us */
1610 	decoder->private_->stream_info.data.stream_info.min_framesize = x;
1611 	used_bits += bits;
1612 
1613 	bits = FLAC__STREAM_METADATA_STREAMINFO_MAX_FRAME_SIZE_LEN;
1614 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_MAX_FRAME_SIZE_LEN))
1615 		return false; /* read_callback_ sets the state for us */
1616 	decoder->private_->stream_info.data.stream_info.max_framesize = x;
1617 	used_bits += bits;
1618 
1619 	bits = FLAC__STREAM_METADATA_STREAMINFO_SAMPLE_RATE_LEN;
1620 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_SAMPLE_RATE_LEN))
1621 		return false; /* read_callback_ sets the state for us */
1622 	decoder->private_->stream_info.data.stream_info.sample_rate = x;
1623 	used_bits += bits;
1624 
1625 	bits = FLAC__STREAM_METADATA_STREAMINFO_CHANNELS_LEN;
1626 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_CHANNELS_LEN))
1627 		return false; /* read_callback_ sets the state for us */
1628 	decoder->private_->stream_info.data.stream_info.channels = x+1;
1629 	used_bits += bits;
1630 
1631 	bits = FLAC__STREAM_METADATA_STREAMINFO_BITS_PER_SAMPLE_LEN;
1632 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_BITS_PER_SAMPLE_LEN))
1633 		return false; /* read_callback_ sets the state for us */
1634 	decoder->private_->stream_info.data.stream_info.bits_per_sample = x+1;
1635 	used_bits += bits;
1636 
1637 	bits = FLAC__STREAM_METADATA_STREAMINFO_TOTAL_SAMPLES_LEN;
1638 	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))
1639 		return false; /* read_callback_ sets the state for us */
1640 	used_bits += bits;
1641 
1642 	if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, decoder->private_->stream_info.data.stream_info.md5sum, 16))
1643 		return false; /* read_callback_ sets the state for us */
1644 	used_bits += 16*8;
1645 
1646 	/* skip the rest of the block */
1647 	FLAC__ASSERT(used_bits % 8 == 0);
1648 	length -= (used_bits / 8);
1649 	if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, length))
1650 		return false; /* read_callback_ sets the state for us */
1651 
1652 	return true;
1653 }
1654 
read_metadata_seektable_(FLAC__StreamDecoder * decoder,FLAC__bool is_last,unsigned length)1655 FLAC__bool read_metadata_seektable_(FLAC__StreamDecoder *decoder, FLAC__bool is_last, unsigned length)
1656 {
1657 	FLAC__uint32 i, x;
1658 	FLAC__uint64 xx;
1659 
1660 	FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1661 
1662 	decoder->private_->seek_table.type = FLAC__METADATA_TYPE_SEEKTABLE;
1663 	decoder->private_->seek_table.is_last = is_last;
1664 	decoder->private_->seek_table.length = length;
1665 
1666 	decoder->private_->seek_table.data.seek_table.num_points = length / FLAC__STREAM_METADATA_SEEKPOINT_LENGTH;
1667 
1668 	/* use realloc since we may pass through here several times (e.g. after seeking) */
1669 	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)))) {
1670 		decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1671 		return false;
1672 	}
1673 	for(i = 0; i < decoder->private_->seek_table.data.seek_table.num_points; i++) {
1674 		if(!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &xx, FLAC__STREAM_METADATA_SEEKPOINT_SAMPLE_NUMBER_LEN))
1675 			return false; /* read_callback_ sets the state for us */
1676 		decoder->private_->seek_table.data.seek_table.points[i].sample_number = xx;
1677 
1678 		if(!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &xx, FLAC__STREAM_METADATA_SEEKPOINT_STREAM_OFFSET_LEN))
1679 			return false; /* read_callback_ sets the state for us */
1680 		decoder->private_->seek_table.data.seek_table.points[i].stream_offset = xx;
1681 
1682 		if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_SEEKPOINT_FRAME_SAMPLES_LEN))
1683 			return false; /* read_callback_ sets the state for us */
1684 		decoder->private_->seek_table.data.seek_table.points[i].frame_samples = x;
1685 	}
1686 	length -= (decoder->private_->seek_table.data.seek_table.num_points * FLAC__STREAM_METADATA_SEEKPOINT_LENGTH);
1687 	/* if there is a partial point left, skip over it */
1688 	if(length > 0) {
1689 		/*@@@ do a send_error_to_client_() here?  there's an argument for either way */
1690 		if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, length))
1691 			return false; /* read_callback_ sets the state for us */
1692 	}
1693 
1694 	return true;
1695 }
1696 
read_metadata_vorbiscomment_(FLAC__StreamDecoder * decoder,FLAC__StreamMetadata_VorbisComment * obj,unsigned length)1697 FLAC__bool read_metadata_vorbiscomment_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_VorbisComment *obj, unsigned length)
1698 {
1699 	FLAC__uint32 i;
1700 
1701 	FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1702 
1703 	/* read vendor string */
1704 	if (length >= 8) {
1705 		length -= 8; /* vendor string length + num comments entries alone take 8 bytes */
1706 		FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN == 32);
1707 		if (!FLAC__bitreader_read_uint32_little_endian(decoder->private_->input, &obj->vendor_string.length))
1708 			return false; /* read_callback_ sets the state for us */
1709 		if (obj->vendor_string.length > 0) {
1710 			if (length < obj->vendor_string.length) {
1711 				obj->vendor_string.length = 0;
1712 				obj->vendor_string.entry = 0;
1713 				goto skip;
1714 			}
1715 			else
1716 				length -= obj->vendor_string.length;
1717 			if (0 == (obj->vendor_string.entry = safe_malloc_add_2op_(obj->vendor_string.length, /*+*/1))) {
1718 				decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1719 				return false;
1720 			}
1721 			if (!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, obj->vendor_string.entry, obj->vendor_string.length))
1722 				return false; /* read_callback_ sets the state for us */
1723 			obj->vendor_string.entry[obj->vendor_string.length] = '\0';
1724 		}
1725 		else
1726 			obj->vendor_string.entry = 0;
1727 
1728 		/* read num comments */
1729 		FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_NUM_COMMENTS_LEN == 32);
1730 		if (!FLAC__bitreader_read_uint32_little_endian(decoder->private_->input, &obj->num_comments))
1731 			return false; /* read_callback_ sets the state for us */
1732 
1733 		/* read comments */
1734 		if (obj->num_comments > 100000) {
1735 			/* Possibly malicious file. */
1736 			obj->num_comments = 0;
1737 			return false;
1738 		}
1739 		if (obj->num_comments > 0) {
1740 			if (0 == (obj->comments = safe_malloc_mul_2op_p(obj->num_comments, /*times*/sizeof(FLAC__StreamMetadata_VorbisComment_Entry)))) {
1741 				obj->num_comments = 0;
1742 				decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1743 				obj->num_comments = 0;
1744 				return false;
1745 			}
1746 			for (i = 0; i < obj->num_comments; i++) {
1747 				/* Initialize here just to make sure. */
1748 				obj->comments[i].length = 0;
1749 				obj->comments[i].entry = 0;
1750 
1751 				FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN == 32);
1752 				if (length < 4) {
1753 					obj->num_comments = i;
1754 					goto skip;
1755 				}
1756 				else
1757 					length -= 4;
1758 				if (!FLAC__bitreader_read_uint32_little_endian(decoder->private_->input, &obj->comments[i].length)) {
1759 					obj->num_comments = i;
1760 					return false; /* read_callback_ sets the state for us */
1761 				}
1762 				if (obj->comments[i].length > 0) {
1763 					if (length < obj->comments[i].length) {
1764 						obj->num_comments = i;
1765 						goto skip;
1766 					}
1767 					else
1768 						length -= obj->comments[i].length;
1769 					if (0 == (obj->comments[i].entry = safe_malloc_add_2op_(obj->comments[i].length, /*+*/1))) {
1770 						decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1771 						return false;
1772 					}
1773 					memset (obj->comments[i].entry, 0, obj->comments[i].length) ;
1774 					if (!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, obj->comments[i].entry, obj->comments[i].length)) {
1775 						obj->num_comments = i;
1776 						goto skip;
1777 					}
1778 					obj->comments[i].entry[obj->comments[i].length] = '\0';
1779 				}
1780 				else
1781 					obj->comments[i].entry = 0;
1782 			}
1783 		}
1784 	}
1785 
1786   skip:
1787 	if (length > 0) {
1788 		/* length > 0 can only happen on files with invalid data in comments */
1789 		if(obj->num_comments < 1) {
1790 			free(obj->comments);
1791 			obj->comments = NULL;
1792 		}
1793 		if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, length))
1794 			return false; /* read_callback_ sets the state for us */
1795 	}
1796 
1797 	return true;
1798 }
1799 
read_metadata_cuesheet_(FLAC__StreamDecoder * decoder,FLAC__StreamMetadata_CueSheet * obj)1800 FLAC__bool read_metadata_cuesheet_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_CueSheet *obj)
1801 {
1802 	FLAC__uint32 i, j, x;
1803 
1804 	FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1805 
1806 	memset(obj, 0, sizeof(FLAC__StreamMetadata_CueSheet));
1807 
1808 	FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_MEDIA_CATALOG_NUMBER_LEN % 8 == 0);
1809 	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))
1810 		return false; /* read_callback_ sets the state for us */
1811 
1812 	if(!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &obj->lead_in, FLAC__STREAM_METADATA_CUESHEET_LEAD_IN_LEN))
1813 		return false; /* read_callback_ sets the state for us */
1814 
1815 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_IS_CD_LEN))
1816 		return false; /* read_callback_ sets the state for us */
1817 	obj->is_cd = x? true : false;
1818 
1819 	if(!FLAC__bitreader_skip_bits_no_crc(decoder->private_->input, FLAC__STREAM_METADATA_CUESHEET_RESERVED_LEN))
1820 		return false; /* read_callback_ sets the state for us */
1821 
1822 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_NUM_TRACKS_LEN))
1823 		return false; /* read_callback_ sets the state for us */
1824 	obj->num_tracks = x;
1825 
1826 	if(obj->num_tracks > 0) {
1827 		if(0 == (obj->tracks = safe_calloc_(obj->num_tracks, sizeof(FLAC__StreamMetadata_CueSheet_Track)))) {
1828 			decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1829 			return false;
1830 		}
1831 		for(i = 0; i < obj->num_tracks; i++) {
1832 			FLAC__StreamMetadata_CueSheet_Track *track = &obj->tracks[i];
1833 			if(!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &track->offset, FLAC__STREAM_METADATA_CUESHEET_TRACK_OFFSET_LEN))
1834 				return false; /* read_callback_ sets the state for us */
1835 
1836 			if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_TRACK_NUMBER_LEN))
1837 				return false; /* read_callback_ sets the state for us */
1838 			track->number = (FLAC__byte)x;
1839 
1840 			FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_TRACK_ISRC_LEN % 8 == 0);
1841 			if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, (FLAC__byte*)track->isrc, FLAC__STREAM_METADATA_CUESHEET_TRACK_ISRC_LEN/8))
1842 				return false; /* read_callback_ sets the state for us */
1843 
1844 			if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_TRACK_TYPE_LEN))
1845 				return false; /* read_callback_ sets the state for us */
1846 			track->type = x;
1847 
1848 			if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_TRACK_PRE_EMPHASIS_LEN))
1849 				return false; /* read_callback_ sets the state for us */
1850 			track->pre_emphasis = x;
1851 
1852 			if(!FLAC__bitreader_skip_bits_no_crc(decoder->private_->input, FLAC__STREAM_METADATA_CUESHEET_TRACK_RESERVED_LEN))
1853 				return false; /* read_callback_ sets the state for us */
1854 
1855 			if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_TRACK_NUM_INDICES_LEN))
1856 				return false; /* read_callback_ sets the state for us */
1857 			track->num_indices = (FLAC__byte)x;
1858 
1859 			if(track->num_indices > 0) {
1860 				if(0 == (track->indices = safe_calloc_(track->num_indices, sizeof(FLAC__StreamMetadata_CueSheet_Index)))) {
1861 					decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1862 					return false;
1863 				}
1864 				for(j = 0; j < track->num_indices; j++) {
1865 					FLAC__StreamMetadata_CueSheet_Index *indx = &track->indices[j];
1866 					if(!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &indx->offset, FLAC__STREAM_METADATA_CUESHEET_INDEX_OFFSET_LEN))
1867 						return false; /* read_callback_ sets the state for us */
1868 
1869 					if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_INDEX_NUMBER_LEN))
1870 						return false; /* read_callback_ sets the state for us */
1871 					indx->number = (FLAC__byte)x;
1872 
1873 					if(!FLAC__bitreader_skip_bits_no_crc(decoder->private_->input, FLAC__STREAM_METADATA_CUESHEET_INDEX_RESERVED_LEN))
1874 						return false; /* read_callback_ sets the state for us */
1875 				}
1876 			}
1877 		}
1878 	}
1879 
1880 	return true;
1881 }
1882 
read_metadata_picture_(FLAC__StreamDecoder * decoder,FLAC__StreamMetadata_Picture * obj)1883 FLAC__bool read_metadata_picture_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_Picture *obj)
1884 {
1885 	FLAC__uint32 x;
1886 
1887 	FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
1888 
1889 	/* read type */
1890 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_PICTURE_TYPE_LEN))
1891 		return false; /* read_callback_ sets the state for us */
1892 	obj->type = x;
1893 
1894 	/* read MIME type */
1895 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_PICTURE_MIME_TYPE_LENGTH_LEN))
1896 		return false; /* read_callback_ sets the state for us */
1897 	if(0 == (obj->mime_type = 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, (FLAC__byte*)obj->mime_type, x))
1903 			return false; /* read_callback_ sets the state for us */
1904 	}
1905 	obj->mime_type[x] = '\0';
1906 
1907 	/* read description */
1908 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_PICTURE_DESCRIPTION_LENGTH_LEN))
1909 		return false; /* read_callback_ sets the state for us */
1910 	if(0 == (obj->description = safe_malloc_add_2op_(x, /*+*/1))) {
1911 		decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1912 		return false;
1913 	}
1914 	if(x > 0) {
1915 		if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, obj->description, x))
1916 			return false; /* read_callback_ sets the state for us */
1917 	}
1918 	obj->description[x] = '\0';
1919 
1920 	/* read width */
1921 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &obj->width, FLAC__STREAM_METADATA_PICTURE_WIDTH_LEN))
1922 		return false; /* read_callback_ sets the state for us */
1923 
1924 	/* read height */
1925 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &obj->height, FLAC__STREAM_METADATA_PICTURE_HEIGHT_LEN))
1926 		return false; /* read_callback_ sets the state for us */
1927 
1928 	/* read depth */
1929 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &obj->depth, FLAC__STREAM_METADATA_PICTURE_DEPTH_LEN))
1930 		return false; /* read_callback_ sets the state for us */
1931 
1932 	/* read colors */
1933 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &obj->colors, FLAC__STREAM_METADATA_PICTURE_COLORS_LEN))
1934 		return false; /* read_callback_ sets the state for us */
1935 
1936 	/* read data */
1937 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &(obj->data_length), FLAC__STREAM_METADATA_PICTURE_DATA_LENGTH_LEN))
1938 		return false; /* read_callback_ sets the state for us */
1939 	if(0 == (obj->data = safe_malloc_(obj->data_length))) {
1940 		decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
1941 		return false;
1942 	}
1943 	if(obj->data_length > 0) {
1944 		if(!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, obj->data, obj->data_length))
1945 			return false; /* read_callback_ sets the state for us */
1946 	}
1947 
1948 	return true;
1949 }
1950 
skip_id3v2_tag_(FLAC__StreamDecoder * decoder)1951 FLAC__bool skip_id3v2_tag_(FLAC__StreamDecoder *decoder)
1952 {
1953 	FLAC__uint32 x;
1954 	unsigned i, skip;
1955 
1956 	/* skip the version and flags bytes */
1957 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 24))
1958 		return false; /* read_callback_ sets the state for us */
1959 	/* get the size (in bytes) to skip */
1960 	skip = 0;
1961 	for(i = 0; i < 4; i++) {
1962 		if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
1963 			return false; /* read_callback_ sets the state for us */
1964 		skip <<= 7;
1965 		skip |= (x & 0x7f);
1966 	}
1967 	/* skip the rest of the tag */
1968 	if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, skip))
1969 		return false; /* read_callback_ sets the state for us */
1970 	return true;
1971 }
1972 
frame_sync_(FLAC__StreamDecoder * decoder)1973 FLAC__bool frame_sync_(FLAC__StreamDecoder *decoder)
1974 {
1975 	FLAC__uint32 x;
1976 	FLAC__bool first = true;
1977 
1978 	/* If we know the total number of samples in the stream, stop if we've read that many. */
1979 	/* This will stop us, for example, from wasting time trying to sync on an ID3V1 tag. */
1980 	if(FLAC__stream_decoder_get_total_samples(decoder) > 0) {
1981 		if(decoder->private_->samples_decoded >= FLAC__stream_decoder_get_total_samples(decoder)) {
1982 			decoder->protected_->state = FLAC__STREAM_DECODER_END_OF_STREAM;
1983 			return true;
1984 		}
1985 	}
1986 
1987 	/* make sure we're byte aligned */
1988 	if(!FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input)) {
1989 		if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__bitreader_bits_left_for_byte_alignment(decoder->private_->input)))
1990 			return false; /* read_callback_ sets the state for us */
1991 	}
1992 
1993 	while(1) {
1994 		if(decoder->private_->cached) {
1995 			x = (FLAC__uint32)decoder->private_->lookahead;
1996 			decoder->private_->cached = false;
1997 		}
1998 		else {
1999 			if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
2000 				return false; /* read_callback_ sets the state for us */
2001 		}
2002 		if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
2003 			decoder->private_->header_warmup[0] = (FLAC__byte)x;
2004 			if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
2005 				return false; /* read_callback_ sets the state for us */
2006 
2007 			/* 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 */
2008 			/* else we have to check if the second byte is the end of a sync code */
2009 			if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
2010 				decoder->private_->lookahead = (FLAC__byte)x;
2011 				decoder->private_->cached = true;
2012 			}
2013 			else if(x >> 1 == 0x7c) { /* MAGIC NUMBER for the last 6 sync bits and reserved 7th bit */
2014 				decoder->private_->header_warmup[1] = (FLAC__byte)x;
2015 				decoder->protected_->state = FLAC__STREAM_DECODER_READ_FRAME;
2016 				return true;
2017 			}
2018 		}
2019 		if(first) {
2020 			send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
2021 			first = false;
2022 		}
2023 	}
2024 
2025 	return true;
2026 }
2027 
read_frame_(FLAC__StreamDecoder * decoder,FLAC__bool * got_a_frame,FLAC__bool do_full_decode)2028 FLAC__bool read_frame_(FLAC__StreamDecoder *decoder, FLAC__bool *got_a_frame, FLAC__bool do_full_decode)
2029 {
2030 	unsigned channel;
2031 	unsigned i;
2032 	FLAC__int32 mid, side;
2033 	unsigned frame_crc; /* the one we calculate from the input stream */
2034 	FLAC__uint32 x;
2035 
2036 	*got_a_frame = false;
2037 
2038 	/* init the CRC */
2039 	frame_crc = 0;
2040 	frame_crc = FLAC__CRC16_UPDATE(decoder->private_->header_warmup[0], frame_crc);
2041 	frame_crc = FLAC__CRC16_UPDATE(decoder->private_->header_warmup[1], frame_crc);
2042 	FLAC__bitreader_reset_read_crc16(decoder->private_->input, (FLAC__uint16)frame_crc);
2043 
2044 	if(!read_frame_header_(decoder))
2045 		return false;
2046 	if(decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) /* means we didn't sync on a valid header */
2047 		return true;
2048 	if(!allocate_output_(decoder, decoder->private_->frame.header.blocksize, decoder->private_->frame.header.channels))
2049 		return false;
2050 	for(channel = 0; channel < decoder->private_->frame.header.channels; channel++) {
2051 		/*
2052 		 * first figure the correct bits-per-sample of the subframe
2053 		 */
2054 		unsigned bps = decoder->private_->frame.header.bits_per_sample;
2055 		switch(decoder->private_->frame.header.channel_assignment) {
2056 			case FLAC__CHANNEL_ASSIGNMENT_INDEPENDENT:
2057 				/* no adjustment needed */
2058 				break;
2059 			case FLAC__CHANNEL_ASSIGNMENT_LEFT_SIDE:
2060 				FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
2061 				if(channel == 1)
2062 					bps++;
2063 				break;
2064 			case FLAC__CHANNEL_ASSIGNMENT_RIGHT_SIDE:
2065 				FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
2066 				if(channel == 0)
2067 					bps++;
2068 				break;
2069 			case FLAC__CHANNEL_ASSIGNMENT_MID_SIDE:
2070 				FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
2071 				if(channel == 1)
2072 					bps++;
2073 				break;
2074 			default:
2075 				FLAC__ASSERT(0);
2076 		}
2077 		/*
2078 		 * now read it
2079 		 */
2080 		if(!read_subframe_(decoder, channel, bps, do_full_decode))
2081 			return false;
2082 		if(decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) /* means bad sync or got corruption */
2083 			return true;
2084 	}
2085 	if(!read_zero_padding_(decoder))
2086 		return false;
2087 	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) */
2088 		return true;
2089 
2090 	/*
2091 	 * Read the frame CRC-16 from the footer and check
2092 	 */
2093 	frame_crc = FLAC__bitreader_get_read_crc16(decoder->private_->input);
2094 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__FRAME_FOOTER_CRC_LEN))
2095 		return false; /* read_callback_ sets the state for us */
2096 	if(frame_crc == x) {
2097 		if(do_full_decode) {
2098 			/* Undo any special channel coding */
2099 			switch(decoder->private_->frame.header.channel_assignment) {
2100 				case FLAC__CHANNEL_ASSIGNMENT_INDEPENDENT:
2101 					/* do nothing */
2102 					break;
2103 				case FLAC__CHANNEL_ASSIGNMENT_LEFT_SIDE:
2104 					FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
2105 					for(i = 0; i < decoder->private_->frame.header.blocksize; i++)
2106 						decoder->private_->output[1][i] = decoder->private_->output[0][i] - decoder->private_->output[1][i];
2107 					break;
2108 				case FLAC__CHANNEL_ASSIGNMENT_RIGHT_SIDE:
2109 					FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
2110 					for(i = 0; i < decoder->private_->frame.header.blocksize; i++)
2111 						decoder->private_->output[0][i] += decoder->private_->output[1][i];
2112 					break;
2113 				case FLAC__CHANNEL_ASSIGNMENT_MID_SIDE:
2114 					FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
2115 					for(i = 0; i < decoder->private_->frame.header.blocksize; i++) {
2116 #if 1
2117 						mid = decoder->private_->output[0][i];
2118 						side = decoder->private_->output[1][i];
2119 						mid = ((uint32_t) mid) << 1;
2120 						mid |= (side & 1); /* i.e. if 'side' is odd... */
2121 						decoder->private_->output[0][i] = (mid + side) >> 1;
2122 						decoder->private_->output[1][i] = (mid - side) >> 1;
2123 #else
2124 						/* OPT: without 'side' temp variable */
2125 						mid = (decoder->private_->output[0][i] << 1) | (decoder->private_->output[1][i] & 1); /* i.e. if 'side' is odd... */
2126 						decoder->private_->output[0][i] = (mid + decoder->private_->output[1][i]) >> 1;
2127 						decoder->private_->output[1][i] = (mid - decoder->private_->output[1][i]) >> 1;
2128 #endif
2129 					}
2130 					break;
2131 				default:
2132 					FLAC__ASSERT(0);
2133 					break;
2134 			}
2135 		}
2136 	}
2137 	else {
2138 		/* Bad frame, emit error and zero the output signal */
2139 		send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_FRAME_CRC_MISMATCH);
2140 		if(do_full_decode) {
2141 			for(channel = 0; channel < decoder->private_->frame.header.channels; channel++) {
2142 				memset(decoder->private_->output[channel], 0, sizeof(FLAC__int32) * decoder->private_->frame.header.blocksize);
2143 			}
2144 		}
2145 	}
2146 
2147 	*got_a_frame = true;
2148 
2149 	/* we wait to update fixed_block_size until here, when we're sure we've got a proper frame and hence a correct blocksize */
2150 	if(decoder->private_->next_fixed_block_size)
2151 		decoder->private_->fixed_block_size = decoder->private_->next_fixed_block_size;
2152 
2153 	/* put the latest values into the public section of the decoder instance */
2154 	decoder->protected_->channels = decoder->private_->frame.header.channels;
2155 	decoder->protected_->channel_assignment = decoder->private_->frame.header.channel_assignment;
2156 	decoder->protected_->bits_per_sample = decoder->private_->frame.header.bits_per_sample;
2157 	decoder->protected_->sample_rate = decoder->private_->frame.header.sample_rate;
2158 	decoder->protected_->blocksize = decoder->private_->frame.header.blocksize;
2159 
2160 	FLAC__ASSERT(decoder->private_->frame.header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER);
2161 	decoder->private_->samples_decoded = decoder->private_->frame.header.number.sample_number + decoder->private_->frame.header.blocksize;
2162 
2163 	/* write it */
2164 	if(do_full_decode) {
2165 		if(write_audio_frame_to_client_(decoder, &decoder->private_->frame, (const FLAC__int32 * const *)decoder->private_->output) != FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE)
2166 			return false;
2167 	}
2168 
2169 	decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2170 	return true;
2171 }
2172 
read_frame_header_(FLAC__StreamDecoder * decoder)2173 FLAC__bool read_frame_header_(FLAC__StreamDecoder *decoder)
2174 {
2175 	FLAC__uint32 x;
2176 	FLAC__uint64 xx;
2177 	unsigned i, blocksize_hint = 0, sample_rate_hint = 0;
2178 	FLAC__byte crc8, raw_header[16]; /* MAGIC NUMBER based on the maximum frame header size, including CRC */
2179 	unsigned raw_header_len;
2180 	FLAC__bool is_unparseable = false;
2181 
2182 	FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
2183 
2184 	/* init the raw header with the saved bits from synchronization */
2185 	raw_header[0] = decoder->private_->header_warmup[0];
2186 	raw_header[1] = decoder->private_->header_warmup[1];
2187 	raw_header_len = 2;
2188 
2189 	/* check to make sure that reserved bit is 0 */
2190 	if(raw_header[1] & 0x02) /* MAGIC NUMBER */
2191 		is_unparseable = true;
2192 
2193 	/*
2194 	 * Note that along the way as we read the header, we look for a sync
2195 	 * code inside.  If we find one it would indicate that our original
2196 	 * sync was bad since there cannot be a sync code in a valid header.
2197 	 *
2198 	 * Three kinds of things can go wrong when reading the frame header:
2199 	 *  1) We may have sync'ed incorrectly and not landed on a frame header.
2200 	 *     If we don't find a sync code, it can end up looking like we read
2201 	 *     a valid but unparseable header, until getting to the frame header
2202 	 *     CRC.  Even then we could get a false positive on the CRC.
2203 	 *  2) We may have sync'ed correctly but on an unparseable frame (from a
2204 	 *     future encoder).
2205 	 *  3) We may be on a damaged frame which appears valid but unparseable.
2206 	 *
2207 	 * For all these reasons, we try and read a complete frame header as
2208 	 * long as it seems valid, even if unparseable, up until the frame
2209 	 * header CRC.
2210 	 */
2211 
2212 	/*
2213 	 * read in the raw header as bytes so we can CRC it, and parse it on the way
2214 	 */
2215 	for(i = 0; i < 2; i++) {
2216 		if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
2217 			return false; /* read_callback_ sets the state for us */
2218 		if(x == 0xff) { /* MAGIC NUMBER for the first 8 frame sync bits */
2219 			/* if we get here it means our original sync was erroneous since the sync code cannot appear in the header */
2220 			decoder->private_->lookahead = (FLAC__byte)x;
2221 			decoder->private_->cached = true;
2222 			send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
2223 			decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2224 			return true;
2225 		}
2226 		raw_header[raw_header_len++] = (FLAC__byte)x;
2227 	}
2228 
2229 	switch(x = raw_header[2] >> 4) {
2230 		case 0:
2231 			is_unparseable = true;
2232 			break;
2233 		case 1:
2234 			decoder->private_->frame.header.blocksize = 192;
2235 			break;
2236 		case 2:
2237 		case 3:
2238 		case 4:
2239 		case 5:
2240 			decoder->private_->frame.header.blocksize = 576 << (x-2);
2241 			break;
2242 		case 6:
2243 		case 7:
2244 			blocksize_hint = x;
2245 			break;
2246 		case 8:
2247 		case 9:
2248 		case 10:
2249 		case 11:
2250 		case 12:
2251 		case 13:
2252 		case 14:
2253 		case 15:
2254 			decoder->private_->frame.header.blocksize = 256 << (x-8);
2255 			break;
2256 		default:
2257 			FLAC__ASSERT(0);
2258 			break;
2259 	}
2260 
2261 	switch(x = raw_header[2] & 0x0f) {
2262 		case 0:
2263 			if(decoder->private_->has_stream_info)
2264 				decoder->private_->frame.header.sample_rate = decoder->private_->stream_info.data.stream_info.sample_rate;
2265 			else
2266 				is_unparseable = true;
2267 			break;
2268 		case 1:
2269 			decoder->private_->frame.header.sample_rate = 88200;
2270 			break;
2271 		case 2:
2272 			decoder->private_->frame.header.sample_rate = 176400;
2273 			break;
2274 		case 3:
2275 			decoder->private_->frame.header.sample_rate = 192000;
2276 			break;
2277 		case 4:
2278 			decoder->private_->frame.header.sample_rate = 8000;
2279 			break;
2280 		case 5:
2281 			decoder->private_->frame.header.sample_rate = 16000;
2282 			break;
2283 		case 6:
2284 			decoder->private_->frame.header.sample_rate = 22050;
2285 			break;
2286 		case 7:
2287 			decoder->private_->frame.header.sample_rate = 24000;
2288 			break;
2289 		case 8:
2290 			decoder->private_->frame.header.sample_rate = 32000;
2291 			break;
2292 		case 9:
2293 			decoder->private_->frame.header.sample_rate = 44100;
2294 			break;
2295 		case 10:
2296 			decoder->private_->frame.header.sample_rate = 48000;
2297 			break;
2298 		case 11:
2299 			decoder->private_->frame.header.sample_rate = 96000;
2300 			break;
2301 		case 12:
2302 		case 13:
2303 		case 14:
2304 			sample_rate_hint = x;
2305 			break;
2306 		case 15:
2307 			send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
2308 			decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2309 			return true;
2310 		default:
2311 			FLAC__ASSERT(0);
2312 	}
2313 
2314 	x = (unsigned)(raw_header[3] >> 4);
2315 	if(x & 8) {
2316 		decoder->private_->frame.header.channels = 2;
2317 		switch(x & 7) {
2318 			case 0:
2319 				decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_LEFT_SIDE;
2320 				break;
2321 			case 1:
2322 				decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_RIGHT_SIDE;
2323 				break;
2324 			case 2:
2325 				decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_MID_SIDE;
2326 				break;
2327 			default:
2328 				is_unparseable = true;
2329 				break;
2330 		}
2331 	}
2332 	else {
2333 		decoder->private_->frame.header.channels = (unsigned)x + 1;
2334 		decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_INDEPENDENT;
2335 	}
2336 
2337 	switch(x = (unsigned)(raw_header[3] & 0x0e) >> 1) {
2338 		case 0:
2339 			if(decoder->private_->has_stream_info)
2340 				decoder->private_->frame.header.bits_per_sample = decoder->private_->stream_info.data.stream_info.bits_per_sample;
2341 			else
2342 				is_unparseable = true;
2343 			break;
2344 		case 1:
2345 			decoder->private_->frame.header.bits_per_sample = 8;
2346 			break;
2347 		case 2:
2348 			decoder->private_->frame.header.bits_per_sample = 12;
2349 			break;
2350 		case 4:
2351 			decoder->private_->frame.header.bits_per_sample = 16;
2352 			break;
2353 		case 5:
2354 			decoder->private_->frame.header.bits_per_sample = 20;
2355 			break;
2356 		case 6:
2357 			decoder->private_->frame.header.bits_per_sample = 24;
2358 			break;
2359 		case 3:
2360 		case 7:
2361 			is_unparseable = true;
2362 			break;
2363 		default:
2364 			FLAC__ASSERT(0);
2365 			break;
2366 	}
2367 
2368 	/* check to make sure that reserved bit is 0 */
2369 	if(raw_header[3] & 0x01) /* MAGIC NUMBER */
2370 		is_unparseable = true;
2371 
2372 	/* read the frame's starting sample number (or frame number as the case may be) */
2373 	if(
2374 		raw_header[1] & 0x01 ||
2375 		/*@@@ 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 */
2376 		(decoder->private_->has_stream_info && decoder->private_->stream_info.data.stream_info.min_blocksize != decoder->private_->stream_info.data.stream_info.max_blocksize)
2377 	) { /* variable blocksize */
2378 		if(!FLAC__bitreader_read_utf8_uint64(decoder->private_->input, &xx, raw_header, &raw_header_len))
2379 			return false; /* read_callback_ sets the state for us */
2380 		if(xx == FLAC__U64L(0xffffffffffffffff)) { /* i.e. non-UTF8 code... */
2381 			decoder->private_->lookahead = raw_header[raw_header_len-1]; /* back up as much as we can */
2382 			decoder->private_->cached = true;
2383 			send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
2384 			decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2385 			return true;
2386 		}
2387 		decoder->private_->frame.header.number_type = FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER;
2388 		decoder->private_->frame.header.number.sample_number = xx;
2389 	}
2390 	else { /* fixed blocksize */
2391 		if(!FLAC__bitreader_read_utf8_uint32(decoder->private_->input, &x, raw_header, &raw_header_len))
2392 			return false; /* read_callback_ sets the state for us */
2393 		if(x == 0xffffffff) { /* i.e. non-UTF8 code... */
2394 			decoder->private_->lookahead = raw_header[raw_header_len-1]; /* back up as much as we can */
2395 			decoder->private_->cached = true;
2396 			send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
2397 			decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2398 			return true;
2399 		}
2400 		decoder->private_->frame.header.number_type = FLAC__FRAME_NUMBER_TYPE_FRAME_NUMBER;
2401 		decoder->private_->frame.header.number.frame_number = x;
2402 	}
2403 
2404 	if(blocksize_hint) {
2405 		if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
2406 			return false; /* read_callback_ sets the state for us */
2407 		raw_header[raw_header_len++] = (FLAC__byte)x;
2408 		if(blocksize_hint == 7) {
2409 			FLAC__uint32 _x;
2410 			if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &_x, 8))
2411 				return false; /* read_callback_ sets the state for us */
2412 			raw_header[raw_header_len++] = (FLAC__byte)_x;
2413 			x = (x << 8) | _x;
2414 		}
2415 		decoder->private_->frame.header.blocksize = x+1;
2416 	}
2417 
2418 	if(sample_rate_hint) {
2419 		if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
2420 			return false; /* read_callback_ sets the state for us */
2421 		raw_header[raw_header_len++] = (FLAC__byte)x;
2422 		if(sample_rate_hint != 12) {
2423 			FLAC__uint32 _x;
2424 			if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &_x, 8))
2425 				return false; /* read_callback_ sets the state for us */
2426 			raw_header[raw_header_len++] = (FLAC__byte)_x;
2427 			x = (x << 8) | _x;
2428 		}
2429 		if(sample_rate_hint == 12)
2430 			decoder->private_->frame.header.sample_rate = x*1000;
2431 		else if(sample_rate_hint == 13)
2432 			decoder->private_->frame.header.sample_rate = x;
2433 		else
2434 			decoder->private_->frame.header.sample_rate = x*10;
2435 	}
2436 
2437 	/* read the CRC-8 byte */
2438 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
2439 		return false; /* read_callback_ sets the state for us */
2440 	crc8 = (FLAC__byte)x;
2441 
2442 	if(FLAC__crc8(raw_header, raw_header_len) != crc8) {
2443 		send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
2444 		decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2445 		return true;
2446 	}
2447 
2448 	/* calculate the sample number from the frame number if needed */
2449 	decoder->private_->next_fixed_block_size = 0;
2450 	if(decoder->private_->frame.header.number_type == FLAC__FRAME_NUMBER_TYPE_FRAME_NUMBER) {
2451 		x = decoder->private_->frame.header.number.frame_number;
2452 		decoder->private_->frame.header.number_type = FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER;
2453 		if(decoder->private_->fixed_block_size)
2454 			decoder->private_->frame.header.number.sample_number = (FLAC__uint64)decoder->private_->fixed_block_size * (FLAC__uint64)x;
2455 		else if(decoder->private_->has_stream_info) {
2456 			if(decoder->private_->stream_info.data.stream_info.min_blocksize == decoder->private_->stream_info.data.stream_info.max_blocksize) {
2457 				decoder->private_->frame.header.number.sample_number = (FLAC__uint64)decoder->private_->stream_info.data.stream_info.min_blocksize * (FLAC__uint64)x;
2458 				decoder->private_->next_fixed_block_size = decoder->private_->stream_info.data.stream_info.max_blocksize;
2459 			}
2460 			else
2461 				is_unparseable = true;
2462 		}
2463 		else if(x == 0) {
2464 			decoder->private_->frame.header.number.sample_number = 0;
2465 			decoder->private_->next_fixed_block_size = decoder->private_->frame.header.blocksize;
2466 		}
2467 		else {
2468 			/* can only get here if the stream has invalid frame numbering and no STREAMINFO, so assume it's not the last (possibly short) frame */
2469 			decoder->private_->frame.header.number.sample_number = (FLAC__uint64)decoder->private_->frame.header.blocksize * (FLAC__uint64)x;
2470 		}
2471 	}
2472 
2473 	if(is_unparseable) {
2474 		send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
2475 		decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2476 		return true;
2477 	}
2478 
2479 	return true;
2480 }
2481 
read_subframe_(FLAC__StreamDecoder * decoder,unsigned channel,unsigned bps,FLAC__bool do_full_decode)2482 FLAC__bool read_subframe_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode)
2483 {
2484 	FLAC__uint32 x;
2485 	FLAC__bool wasted_bits;
2486 	unsigned i;
2487 
2488 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8)) /* MAGIC NUMBER */
2489 		return false; /* read_callback_ sets the state for us */
2490 
2491 	wasted_bits = (x & 1);
2492 	x &= 0xfe;
2493 
2494 	if(wasted_bits) {
2495 		unsigned u;
2496 		if(!FLAC__bitreader_read_unary_unsigned(decoder->private_->input, &u))
2497 			return false; /* read_callback_ sets the state for us */
2498 		decoder->private_->frame.subframes[channel].wasted_bits = u+1;
2499 		bps -= decoder->private_->frame.subframes[channel].wasted_bits;
2500 	}
2501 	else
2502 		decoder->private_->frame.subframes[channel].wasted_bits = 0;
2503 
2504 	/*
2505 	 * Lots of magic numbers here
2506 	 */
2507 	if(x & 0x80) {
2508 		send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
2509 		decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2510 		return true;
2511 	}
2512 	else if(x == 0) {
2513 		if(!read_subframe_constant_(decoder, channel, bps, do_full_decode))
2514 			return false;
2515 	}
2516 	else if(x == 2) {
2517 		if(!read_subframe_verbatim_(decoder, channel, bps, do_full_decode))
2518 			return false;
2519 	}
2520 	else if(x < 16) {
2521 		send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
2522 		decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2523 		return true;
2524 	}
2525 	else if(x <= 24) {
2526 		if(!read_subframe_fixed_(decoder, channel, bps, (x>>1)&7, do_full_decode))
2527 			return false;
2528 		if(decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) /* means bad sync or got corruption */
2529 			return true;
2530 	}
2531 	else if(x < 64) {
2532 		send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
2533 		decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2534 		return true;
2535 	}
2536 	else {
2537 		if(!read_subframe_lpc_(decoder, channel, bps, ((x>>1)&31)+1, do_full_decode))
2538 			return false;
2539 		if(decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) /* means bad sync or got corruption */
2540 			return true;
2541 	}
2542 
2543 	if(wasted_bits && do_full_decode) {
2544 		x = decoder->private_->frame.subframes[channel].wasted_bits;
2545 		for(i = 0; i < decoder->private_->frame.header.blocksize; i++) {
2546 			uint32_t val = decoder->private_->output[channel][i];
2547 			decoder->private_->output[channel][i] = (val << x);
2548 		}
2549 	}
2550 
2551 	return true;
2552 }
2553 
read_subframe_constant_(FLAC__StreamDecoder * decoder,unsigned channel,unsigned bps,FLAC__bool do_full_decode)2554 FLAC__bool read_subframe_constant_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode)
2555 {
2556 	FLAC__Subframe_Constant *subframe = &decoder->private_->frame.subframes[channel].data.constant;
2557 	FLAC__int32 x;
2558 	unsigned i;
2559 	FLAC__int32 *output = decoder->private_->output[channel];
2560 
2561 	decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_CONSTANT;
2562 
2563 	if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &x, bps))
2564 		return false; /* read_callback_ sets the state for us */
2565 
2566 	subframe->value = x;
2567 
2568 	/* decode the subframe */
2569 	if(do_full_decode) {
2570 		for(i = 0; i < decoder->private_->frame.header.blocksize; i++)
2571 			output[i] = x;
2572 	}
2573 
2574 	return true;
2575 }
2576 
read_subframe_fixed_(FLAC__StreamDecoder * decoder,unsigned channel,unsigned bps,const unsigned order,FLAC__bool do_full_decode)2577 FLAC__bool read_subframe_fixed_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, const unsigned order, FLAC__bool do_full_decode)
2578 {
2579 	FLAC__Subframe_Fixed *subframe = &decoder->private_->frame.subframes[channel].data.fixed;
2580 	FLAC__int32 i32;
2581 	FLAC__uint32 u32;
2582 	unsigned u;
2583 
2584 	decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_FIXED;
2585 
2586 	subframe->residual = decoder->private_->residual[channel];
2587 	subframe->order = order;
2588 
2589 	/* read warm-up samples */
2590 	for(u = 0; u < order; u++) {
2591 		if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i32, bps))
2592 			return false; /* read_callback_ sets the state for us */
2593 		subframe->warmup[u] = i32;
2594 	}
2595 
2596 	/* read entropy coding method info */
2597 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_TYPE_LEN))
2598 		return false; /* read_callback_ sets the state for us */
2599 	subframe->entropy_coding_method.type = (FLAC__EntropyCodingMethodType)u32;
2600 	switch(subframe->entropy_coding_method.type) {
2601 		case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE:
2602 		case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2:
2603 			if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ORDER_LEN))
2604 				return false; /* read_callback_ sets the state for us */
2605 			if(decoder->private_->frame.header.blocksize >> u32 < order) {
2606 				send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
2607 				decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2608 				return true;
2609 			}
2610 			subframe->entropy_coding_method.data.partitioned_rice.order = u32;
2611 			subframe->entropy_coding_method.data.partitioned_rice.contents = &decoder->private_->partitioned_rice_contents[channel];
2612 			break;
2613 		default:
2614 			send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
2615 			decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2616 			return true;
2617 	}
2618 
2619 	/* read residual */
2620 	switch(subframe->entropy_coding_method.type) {
2621 		case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE:
2622 		case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2:
2623 			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))
2624 				return false;
2625 			break;
2626 		default:
2627 			FLAC__ASSERT(0);
2628 	}
2629 
2630 	/* decode the subframe */
2631 	if(do_full_decode) {
2632 		memcpy(decoder->private_->output[channel], subframe->warmup, sizeof(FLAC__int32) * order);
2633 		FLAC__fixed_restore_signal(decoder->private_->residual[channel], decoder->private_->frame.header.blocksize-order, order, decoder->private_->output[channel]+order);
2634 	}
2635 
2636 	return true;
2637 }
2638 
read_subframe_lpc_(FLAC__StreamDecoder * decoder,unsigned channel,unsigned bps,const unsigned order,FLAC__bool do_full_decode)2639 FLAC__bool read_subframe_lpc_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, const unsigned order, FLAC__bool do_full_decode)
2640 {
2641 	FLAC__Subframe_LPC *subframe = &decoder->private_->frame.subframes[channel].data.lpc;
2642 	FLAC__int32 i32;
2643 	FLAC__uint32 u32;
2644 	unsigned u;
2645 
2646 	decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_LPC;
2647 
2648 	subframe->residual = decoder->private_->residual[channel];
2649 	subframe->order = order;
2650 
2651 	/* read warm-up samples */
2652 	for(u = 0; u < order; u++) {
2653 		if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i32, bps))
2654 			return false; /* read_callback_ sets the state for us */
2655 		subframe->warmup[u] = i32;
2656 	}
2657 
2658 	/* read qlp coeff precision */
2659 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__SUBFRAME_LPC_QLP_COEFF_PRECISION_LEN))
2660 		return false; /* read_callback_ sets the state for us */
2661 	if(u32 == (1u << FLAC__SUBFRAME_LPC_QLP_COEFF_PRECISION_LEN) - 1) {
2662 		send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
2663 		decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2664 		return true;
2665 	}
2666 	subframe->qlp_coeff_precision = u32+1;
2667 
2668 	/* read qlp shift */
2669 	if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i32, FLAC__SUBFRAME_LPC_QLP_SHIFT_LEN))
2670 		return false; /* read_callback_ sets the state for us */
2671 	if(i32 < 0) {
2672 		send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
2673 		decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2674 		return true;
2675 	}
2676 	subframe->quantization_level = i32;
2677 
2678 	/* read quantized lp coefficiencts */
2679 	for(u = 0; u < order; u++) {
2680 		if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i32, subframe->qlp_coeff_precision))
2681 			return false; /* read_callback_ sets the state for us */
2682 		subframe->qlp_coeff[u] = i32;
2683 	}
2684 
2685 	/* read entropy coding method info */
2686 	if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_TYPE_LEN))
2687 		return false; /* read_callback_ sets the state for us */
2688 	subframe->entropy_coding_method.type = (FLAC__EntropyCodingMethodType)u32;
2689 	switch(subframe->entropy_coding_method.type) {
2690 		case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE:
2691 		case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2:
2692 			if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ORDER_LEN))
2693 				return false; /* read_callback_ sets the state for us */
2694 			if(decoder->private_->frame.header.blocksize >> u32 < order) {
2695 				send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
2696 				decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2697 				return true;
2698 			}
2699 			subframe->entropy_coding_method.data.partitioned_rice.order = u32;
2700 			subframe->entropy_coding_method.data.partitioned_rice.contents = &decoder->private_->partitioned_rice_contents[channel];
2701 			break;
2702 		default:
2703 			send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
2704 			decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2705 			return true;
2706 	}
2707 
2708 	/* read residual */
2709 	switch(subframe->entropy_coding_method.type) {
2710 		case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE:
2711 		case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2:
2712 			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))
2713 				return false;
2714 			break;
2715 		default:
2716 			FLAC__ASSERT(0);
2717 	}
2718 
2719 	/* decode the subframe */
2720 	if(do_full_decode) {
2721 		memcpy(decoder->private_->output[channel], subframe->warmup, sizeof(FLAC__int32) * order);
2722 		if(bps + subframe->qlp_coeff_precision + FLAC__bitmath_ilog2(order) <= 32)
2723 			if(bps <= 16 && subframe->qlp_coeff_precision <= 16)
2724 				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);
2725 			else
2726 				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);
2727 		else
2728 			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);
2729 	}
2730 
2731 	return true;
2732 }
2733 
read_subframe_verbatim_(FLAC__StreamDecoder * decoder,unsigned channel,unsigned bps,FLAC__bool do_full_decode)2734 FLAC__bool read_subframe_verbatim_(FLAC__StreamDecoder *decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode)
2735 {
2736 	FLAC__Subframe_Verbatim *subframe = &decoder->private_->frame.subframes[channel].data.verbatim;
2737 	FLAC__int32 x, *residual = decoder->private_->residual[channel];
2738 	unsigned i;
2739 
2740 	decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_VERBATIM;
2741 
2742 	subframe->data = residual;
2743 
2744 	for(i = 0; i < decoder->private_->frame.header.blocksize; i++) {
2745 		if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &x, bps))
2746 			return false; /* read_callback_ sets the state for us */
2747 		residual[i] = x;
2748 	}
2749 
2750 	/* decode the subframe */
2751 	if(do_full_decode)
2752 		memcpy(decoder->private_->output[channel], subframe->data, sizeof(FLAC__int32) * decoder->private_->frame.header.blocksize);
2753 
2754 	return true;
2755 }
2756 
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)2757 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)
2758 {
2759 	FLAC__uint32 rice_parameter;
2760 	int i;
2761 	unsigned partition, sample, u;
2762 	const unsigned partitions = 1u << partition_order;
2763 	const unsigned partition_samples = partition_order > 0? decoder->private_->frame.header.blocksize >> partition_order : decoder->private_->frame.header.blocksize - predictor_order;
2764 	const unsigned plen = is_extended? FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2_PARAMETER_LEN : FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN;
2765 	const unsigned pesc = is_extended? FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2_ESCAPE_PARAMETER : FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ESCAPE_PARAMETER;
2766 
2767 	/* invalid predictor and partition orders mush be handled in the callers */
2768 	FLAC__ASSERT(partition_order > 0? partition_samples >= predictor_order : decoder->private_->frame.header.blocksize >= predictor_order);
2769 
2770 	if(!FLAC__format_entropy_coding_method_partitioned_rice_contents_ensure_size(partitioned_rice_contents, flac_max(6u, partition_order))) {
2771 		decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
2772 		return false;
2773 	}
2774 
2775 	sample = 0;
2776 	for(partition = 0; partition < partitions; partition++) {
2777 		if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &rice_parameter, plen))
2778 			return false; /* read_callback_ sets the state for us */
2779 		partitioned_rice_contents->parameters[partition] = rice_parameter;
2780 		if(rice_parameter < pesc) {
2781 			partitioned_rice_contents->raw_bits[partition] = 0;
2782 			u = (partition_order == 0 || partition > 0)? partition_samples : partition_samples - predictor_order;
2783 			if(!FLAC__bitreader_read_rice_signed_block(decoder->private_->input, residual + sample, u, rice_parameter))
2784 				return false; /* read_callback_ sets the state for us */
2785 			sample += u;
2786 		}
2787 		else {
2788 			if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &rice_parameter, FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_RAW_LEN))
2789 				return false; /* read_callback_ sets the state for us */
2790 			partitioned_rice_contents->raw_bits[partition] = rice_parameter;
2791 			for(u = (partition_order == 0 || partition > 0)? 0 : predictor_order; u < partition_samples; u++, sample++) {
2792 				if(!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i, rice_parameter))
2793 					return false; /* read_callback_ sets the state for us */
2794 				residual[sample] = i;
2795 			}
2796 		}
2797 	}
2798 
2799 	return true;
2800 }
2801 
read_zero_padding_(FLAC__StreamDecoder * decoder)2802 FLAC__bool read_zero_padding_(FLAC__StreamDecoder *decoder)
2803 {
2804 	if(!FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input)) {
2805 		FLAC__uint32 zero = 0;
2806 		if(!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &zero, FLAC__bitreader_bits_left_for_byte_alignment(decoder->private_->input)))
2807 			return false; /* read_callback_ sets the state for us */
2808 		if(zero != 0) {
2809 			send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
2810 			decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
2811 		}
2812 	}
2813 	return true;
2814 }
2815 
read_callback_(FLAC__byte buffer[],size_t * bytes,void * client_data)2816 FLAC__bool read_callback_(FLAC__byte buffer[], size_t *bytes, void *client_data)
2817 {
2818 	FLAC__StreamDecoder *decoder = (FLAC__StreamDecoder *)client_data;
2819 
2820 	if(
2821 #if FLAC__HAS_OGG
2822 		/* see [1] HACK NOTE below for why we don't call the eof_callback when decoding Ogg FLAC */
2823 		!decoder->private_->is_ogg &&
2824 #endif
2825 		decoder->private_->eof_callback && decoder->private_->eof_callback(decoder, decoder->private_->client_data)
2826 	) {
2827 		*bytes = 0;
2828 		decoder->protected_->state = FLAC__STREAM_DECODER_END_OF_STREAM;
2829 		return false;
2830 	}
2831 	else if(*bytes > 0) {
2832 		/* While seeking, it is possible for our seek to land in the
2833 		 * middle of audio data that looks exactly like a frame header
2834 		 * from a future version of an encoder.  When that happens, our
2835 		 * error callback will get an
2836 		 * FLAC__STREAM_DECODER_UNPARSEABLE_STREAM and increment its
2837 		 * unparseable_frame_count.  But there is a remote possibility
2838 		 * that it is properly synced at such a "future-codec frame",
2839 		 * so to make sure, we wait to see many "unparseable" errors in
2840 		 * a row before bailing out.
2841 		 */
2842 		if(decoder->private_->is_seeking && decoder->private_->unparseable_frame_count > 20) {
2843 			decoder->protected_->state = FLAC__STREAM_DECODER_ABORTED;
2844 			return false;
2845 		}
2846 		else {
2847 			const FLAC__StreamDecoderReadStatus status =
2848 #if FLAC__HAS_OGG
2849 				decoder->private_->is_ogg?
2850 				read_callback_ogg_aspect_(decoder, buffer, bytes) :
2851 #endif
2852 				decoder->private_->read_callback(decoder, buffer, bytes, decoder->private_->client_data)
2853 			;
2854 			if(status == FLAC__STREAM_DECODER_READ_STATUS_ABORT) {
2855 				decoder->protected_->state = FLAC__STREAM_DECODER_ABORTED;
2856 				return false;
2857 			}
2858 			else if(*bytes == 0) {
2859 				if(
2860 					status == FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM ||
2861 					(
2862 #if FLAC__HAS_OGG
2863 						/* see [1] HACK NOTE below for why we don't call the eof_callback when decoding Ogg FLAC */
2864 						!decoder->private_->is_ogg &&
2865 #endif
2866 						decoder->private_->eof_callback && decoder->private_->eof_callback(decoder, decoder->private_->client_data)
2867 					)
2868 				) {
2869 					decoder->protected_->state = FLAC__STREAM_DECODER_END_OF_STREAM;
2870 					return false;
2871 				}
2872 				else
2873 					return true;
2874 			}
2875 			else
2876 				return true;
2877 		}
2878 	}
2879 	else {
2880 		/* abort to avoid a deadlock */
2881 		decoder->protected_->state = FLAC__STREAM_DECODER_ABORTED;
2882 		return false;
2883 	}
2884 	/* [1] @@@ HACK NOTE: The end-of-stream checking has to be hacked around
2885 	 * for Ogg FLAC.  This is because the ogg decoder aspect can lose sync
2886 	 * and at the same time hit the end of the stream (for example, seeking
2887 	 * to a point that is after the beginning of the last Ogg page).  There
2888 	 * is no way to report an Ogg sync loss through the callbacks (see note
2889 	 * in read_callback_ogg_aspect_()) so it returns CONTINUE with *bytes==0.
2890 	 * So to keep the decoder from stopping at this point we gate the call
2891 	 * to the eof_callback and let the Ogg decoder aspect set the
2892 	 * end-of-stream state when it is needed.
2893 	 */
2894 }
2895 
2896 #if FLAC__HAS_OGG
read_callback_ogg_aspect_(const FLAC__StreamDecoder * decoder,FLAC__byte buffer[],size_t * bytes)2897 FLAC__StreamDecoderReadStatus read_callback_ogg_aspect_(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes)
2898 {
2899 	switch(FLAC__ogg_decoder_aspect_read_callback_wrapper(&decoder->protected_->ogg_decoder_aspect, buffer, bytes, read_callback_proxy_, decoder, decoder->private_->client_data)) {
2900 		case FLAC__OGG_DECODER_ASPECT_READ_STATUS_OK:
2901 			return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
2902 		/* we don't really have a way to handle lost sync via read
2903 		 * callback so we'll let it pass and let the underlying
2904 		 * FLAC decoder catch the error
2905 		 */
2906 		case FLAC__OGG_DECODER_ASPECT_READ_STATUS_LOST_SYNC:
2907 			return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
2908 		case FLAC__OGG_DECODER_ASPECT_READ_STATUS_END_OF_STREAM:
2909 			return FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM;
2910 		case FLAC__OGG_DECODER_ASPECT_READ_STATUS_NOT_FLAC:
2911 		case FLAC__OGG_DECODER_ASPECT_READ_STATUS_UNSUPPORTED_MAPPING_VERSION:
2912 		case FLAC__OGG_DECODER_ASPECT_READ_STATUS_ABORT:
2913 		case FLAC__OGG_DECODER_ASPECT_READ_STATUS_ERROR:
2914 		case FLAC__OGG_DECODER_ASPECT_READ_STATUS_MEMORY_ALLOCATION_ERROR:
2915 			return FLAC__STREAM_DECODER_READ_STATUS_ABORT;
2916 		default:
2917 			FLAC__ASSERT(0);
2918 			/* double protection */
2919 			return FLAC__STREAM_DECODER_READ_STATUS_ABORT;
2920 	}
2921 }
2922 
read_callback_proxy_(const void * void_decoder,FLAC__byte buffer[],size_t * bytes,void * client_data)2923 FLAC__OggDecoderAspectReadStatus read_callback_proxy_(const void *void_decoder, FLAC__byte buffer[], size_t *bytes, void *client_data)
2924 {
2925 	FLAC__StreamDecoder *decoder = (FLAC__StreamDecoder*)void_decoder;
2926 
2927 	switch(decoder->private_->read_callback(decoder, buffer, bytes, client_data)) {
2928 		case FLAC__STREAM_DECODER_READ_STATUS_CONTINUE:
2929 			return FLAC__OGG_DECODER_ASPECT_READ_STATUS_OK;
2930 		case FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM:
2931 			return FLAC__OGG_DECODER_ASPECT_READ_STATUS_END_OF_STREAM;
2932 		case FLAC__STREAM_DECODER_READ_STATUS_ABORT:
2933 			return FLAC__OGG_DECODER_ASPECT_READ_STATUS_ABORT;
2934 		default:
2935 			/* double protection: */
2936 			FLAC__ASSERT(0);
2937 			return FLAC__OGG_DECODER_ASPECT_READ_STATUS_ABORT;
2938 	}
2939 }
2940 #endif
2941 
write_audio_frame_to_client_(FLAC__StreamDecoder * decoder,const FLAC__Frame * frame,const FLAC__int32 * const buffer[])2942 FLAC__StreamDecoderWriteStatus write_audio_frame_to_client_(FLAC__StreamDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[])
2943 {
2944 	if(decoder->private_->is_seeking) {
2945 		FLAC__uint64 this_frame_sample = frame->header.number.sample_number;
2946 		FLAC__uint64 next_frame_sample = this_frame_sample + (FLAC__uint64)frame->header.blocksize;
2947 		FLAC__uint64 target_sample = decoder->private_->target_sample;
2948 
2949 		FLAC__ASSERT(frame->header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER);
2950 
2951 #if FLAC__HAS_OGG
2952 		decoder->private_->got_a_frame = true;
2953 #endif
2954 		decoder->private_->last_frame = *frame; /* save the frame */
2955 		if(this_frame_sample <= target_sample && target_sample < next_frame_sample) { /* we hit our target frame */
2956 			unsigned delta = (unsigned)(target_sample - this_frame_sample);
2957 			/* kick out of seek mode */
2958 			decoder->private_->is_seeking = false;
2959 			/* shift out the samples before target_sample */
2960 			if(delta > 0) {
2961 				unsigned channel;
2962 				const FLAC__int32 *newbuffer[FLAC__MAX_CHANNELS];
2963 				for(channel = 0; channel < frame->header.channels; channel++)
2964 					newbuffer[channel] = buffer[channel] + delta;
2965 				decoder->private_->last_frame.header.blocksize -= delta;
2966 				decoder->private_->last_frame.header.number.sample_number += (FLAC__uint64)delta;
2967 				/* write the relevant samples */
2968 				return decoder->private_->write_callback(decoder, &decoder->private_->last_frame, newbuffer, decoder->private_->client_data);
2969 			}
2970 			else {
2971 				/* write the relevant samples */
2972 				return decoder->private_->write_callback(decoder, frame, buffer, decoder->private_->client_data);
2973 			}
2974 		}
2975 		else {
2976 			return FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE;
2977 		}
2978 	}
2979 	else {
2980 		/*
2981 		 * If we never got STREAMINFO, turn off MD5 checking to save
2982 		 * cycles since we don't have a sum to compare to anyway
2983 		 */
2984 		if(!decoder->private_->has_stream_info)
2985 			decoder->private_->do_md5_checking = false;
2986 		if(decoder->private_->do_md5_checking) {
2987 			if(!FLAC__MD5Accumulate(&decoder->private_->md5context, buffer, frame->header.channels, frame->header.blocksize, (frame->header.bits_per_sample+7) / 8))
2988 				return FLAC__STREAM_DECODER_WRITE_STATUS_ABORT;
2989 		}
2990 		return decoder->private_->write_callback(decoder, frame, buffer, decoder->private_->client_data);
2991 	}
2992 }
2993 
send_error_to_client_(const FLAC__StreamDecoder * decoder,FLAC__StreamDecoderErrorStatus status)2994 void send_error_to_client_(const FLAC__StreamDecoder *decoder, FLAC__StreamDecoderErrorStatus status)
2995 {
2996 	if(!decoder->private_->is_seeking)
2997 		decoder->private_->error_callback(decoder, status, decoder->private_->client_data);
2998 	else if(status == FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM)
2999 		decoder->private_->unparseable_frame_count++;
3000 }
3001 
seek_to_absolute_sample_(FLAC__StreamDecoder * decoder,FLAC__uint64 stream_length,FLAC__uint64 target_sample)3002 FLAC__bool seek_to_absolute_sample_(FLAC__StreamDecoder *decoder, FLAC__uint64 stream_length, FLAC__uint64 target_sample)
3003 {
3004 	FLAC__uint64 first_frame_offset = decoder->private_->first_frame_offset, lower_bound, upper_bound, lower_bound_sample, upper_bound_sample, this_frame_sample;
3005 	FLAC__int64 pos = -1;
3006 	int i;
3007 	unsigned approx_bytes_per_frame;
3008 	FLAC__bool first_seek = true;
3009 	const FLAC__uint64 total_samples = FLAC__stream_decoder_get_total_samples(decoder);
3010 	const unsigned min_blocksize = decoder->private_->stream_info.data.stream_info.min_blocksize;
3011 	const unsigned max_blocksize = decoder->private_->stream_info.data.stream_info.max_blocksize;
3012 	const unsigned max_framesize = decoder->private_->stream_info.data.stream_info.max_framesize;
3013 	const unsigned min_framesize = decoder->private_->stream_info.data.stream_info.min_framesize;
3014 	/* take these from the current frame in case they've changed mid-stream */
3015 	unsigned channels = FLAC__stream_decoder_get_channels(decoder);
3016 	unsigned bps = FLAC__stream_decoder_get_bits_per_sample(decoder);
3017 	const FLAC__StreamMetadata_SeekTable *seek_table = decoder->private_->has_seek_table? &decoder->private_->seek_table.data.seek_table : 0;
3018 
3019 	/* use values from stream info if we didn't decode a frame */
3020 	if(channels == 0)
3021 		channels = decoder->private_->stream_info.data.stream_info.channels;
3022 	if(bps == 0)
3023 		bps = decoder->private_->stream_info.data.stream_info.bits_per_sample;
3024 
3025 	/* we are just guessing here */
3026 	if(max_framesize > 0)
3027 		approx_bytes_per_frame = (max_framesize + min_framesize) / 2 + 1;
3028 	/*
3029 	 * Check if it's a known fixed-blocksize stream.  Note that though
3030 	 * the spec doesn't allow zeroes in the STREAMINFO block, we may
3031 	 * never get a STREAMINFO block when decoding so the value of
3032 	 * min_blocksize might be zero.
3033 	 */
3034 	else if(min_blocksize == max_blocksize && min_blocksize > 0) {
3035 		/* note there are no () around 'bps/8' to keep precision up since it's an integer calulation */
3036 		approx_bytes_per_frame = min_blocksize * channels * bps/8 + 64;
3037 	}
3038 	else
3039 		approx_bytes_per_frame = 4096 * channels * bps/8 + 64;
3040 
3041 	/*
3042 	 * First, we set an upper and lower bound on where in the
3043 	 * stream we will search.  For now we assume the worst case
3044 	 * scenario, which is our best guess at the beginning of
3045 	 * the first frame and end of the stream.
3046 	 */
3047 	lower_bound = first_frame_offset;
3048 	lower_bound_sample = 0;
3049 	upper_bound = stream_length;
3050 	upper_bound_sample = total_samples > 0 ? total_samples : target_sample /*estimate it*/;
3051 
3052 	/*
3053 	 * Now we refine the bounds if we have a seektable with
3054 	 * suitable points.  Note that according to the spec they
3055 	 * must be ordered by ascending sample number.
3056 	 *
3057 	 * Note: to protect against invalid seek tables we will ignore points
3058 	 * that have frame_samples==0 or sample_number>=total_samples
3059 	 */
3060 	if(seek_table) {
3061 		FLAC__uint64 new_lower_bound = lower_bound;
3062 		FLAC__uint64 new_upper_bound = upper_bound;
3063 		FLAC__uint64 new_lower_bound_sample = lower_bound_sample;
3064 		FLAC__uint64 new_upper_bound_sample = upper_bound_sample;
3065 
3066 		/* find the closest seek point <= target_sample, if it exists */
3067 		for(i = (int)seek_table->num_points - 1; i >= 0; i--) {
3068 			if(
3069 				seek_table->points[i].sample_number != FLAC__STREAM_METADATA_SEEKPOINT_PLACEHOLDER &&
3070 				seek_table->points[i].frame_samples > 0 && /* defense against bad seekpoints */
3071 				(total_samples <= 0 || seek_table->points[i].sample_number < total_samples) && /* defense against bad seekpoints */
3072 				seek_table->points[i].sample_number <= target_sample
3073 			)
3074 				break;
3075 		}
3076 		if(i >= 0) { /* i.e. we found a suitable seek point... */
3077 			new_lower_bound = first_frame_offset + seek_table->points[i].stream_offset;
3078 			new_lower_bound_sample = seek_table->points[i].sample_number;
3079 		}
3080 
3081 		/* find the closest seek point > target_sample, if it exists */
3082 		for(i = 0; i < (int)seek_table->num_points; i++) {
3083 			if(
3084 				seek_table->points[i].sample_number != FLAC__STREAM_METADATA_SEEKPOINT_PLACEHOLDER &&
3085 				seek_table->points[i].frame_samples > 0 && /* defense against bad seekpoints */
3086 				(total_samples <= 0 || seek_table->points[i].sample_number < total_samples) && /* defense against bad seekpoints */
3087 				seek_table->points[i].sample_number > target_sample
3088 			)
3089 				break;
3090 		}
3091 		if(i < (int)seek_table->num_points) { /* i.e. we found a suitable seek point... */
3092 			new_upper_bound = first_frame_offset + seek_table->points[i].stream_offset;
3093 			new_upper_bound_sample = seek_table->points[i].sample_number;
3094 		}
3095 		/* final protection against unsorted seek tables; keep original values if bogus */
3096 		if(new_upper_bound >= new_lower_bound) {
3097 			lower_bound = new_lower_bound;
3098 			upper_bound = new_upper_bound;
3099 			lower_bound_sample = new_lower_bound_sample;
3100 			upper_bound_sample = new_upper_bound_sample;
3101 		}
3102 	}
3103 
3104 	FLAC__ASSERT(upper_bound_sample >= lower_bound_sample);
3105 	/* there are 2 insidious ways that the following equality occurs, which
3106 	 * we need to fix:
3107 	 *  1) total_samples is 0 (unknown) and target_sample is 0
3108 	 *  2) total_samples is 0 (unknown) and target_sample happens to be
3109 	 *     exactly equal to the last seek point in the seek table; this
3110 	 *     means there is no seek point above it, and upper_bound_samples
3111 	 *     remains equal to the estimate (of target_samples) we made above
3112 	 * in either case it does not hurt to move upper_bound_sample up by 1
3113 	 */
3114 	if(upper_bound_sample == lower_bound_sample)
3115 		upper_bound_sample++;
3116 
3117 	decoder->private_->target_sample = target_sample;
3118 	while(1) {
3119 		/* check if the bounds are still ok */
3120 		if (lower_bound_sample >= upper_bound_sample || lower_bound > upper_bound) {
3121 			decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3122 			return false;
3123 		}
3124 #ifndef FLAC__INTEGER_ONLY_LIBRARY
3125 		pos = (FLAC__int64)lower_bound + (FLAC__int64)((FLAC__double)(target_sample - lower_bound_sample) / (FLAC__double)(upper_bound_sample - lower_bound_sample) * (FLAC__double)(upper_bound - lower_bound)) - approx_bytes_per_frame;
3126 #else
3127 		/* a little less accurate: */
3128 		if(upper_bound - lower_bound < 0xffffffff)
3129 			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;
3130 		else /* @@@ WATCHOUT, ~2TB limit */
3131 			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;
3132 #endif
3133 		if(pos >= (FLAC__int64)upper_bound)
3134 			pos = (FLAC__int64)upper_bound - 1;
3135 		if(pos < (FLAC__int64)lower_bound)
3136 			pos = (FLAC__int64)lower_bound;
3137 		if(decoder->private_->seek_callback(decoder, (FLAC__uint64)pos, decoder->private_->client_data) != FLAC__STREAM_DECODER_SEEK_STATUS_OK) {
3138 			decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3139 			return false;
3140 		}
3141 		if(!FLAC__stream_decoder_flush(decoder)) {
3142 			/* above call sets the state for us */
3143 			return false;
3144 		}
3145 		/* Now we need to get a frame.  First we need to reset our
3146 		 * unparseable_frame_count; if we get too many unparseable
3147 		 * frames in a row, the read callback will return
3148 		 * FLAC__STREAM_DECODER_READ_STATUS_ABORT, causing
3149 		 * FLAC__stream_decoder_process_single() to return false.
3150 		 */
3151 		decoder->private_->unparseable_frame_count = 0;
3152 		if(!FLAC__stream_decoder_process_single(decoder)) {
3153 			decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3154 			return false;
3155 		}
3156 		/* our write callback will change the state when it gets to the target frame */
3157 		/* 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 */
3158 #if 0
3159 		/*@@@@@@ used to be the following; not clear if the check for end of stream is needed anymore */
3160 		if(decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_SEEKING && decoder->protected_->state != FLAC__STREAM_DECODER_END_OF_STREAM)
3161 			break;
3162 #endif
3163 		if(!decoder->private_->is_seeking)
3164 			break;
3165 
3166 		FLAC__ASSERT(decoder->private_->last_frame.header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER);
3167 		this_frame_sample = decoder->private_->last_frame.header.number.sample_number;
3168 
3169 		if (0 == decoder->private_->samples_decoded || (this_frame_sample + decoder->private_->last_frame.header.blocksize >= upper_bound_sample && !first_seek)) {
3170 			if (pos == (FLAC__int64)lower_bound) {
3171 				/* can't move back any more than the first frame, something is fatally wrong */
3172 				decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3173 				return false;
3174 			}
3175 			/* our last move backwards wasn't big enough, try again */
3176 			approx_bytes_per_frame = approx_bytes_per_frame? approx_bytes_per_frame * 2 : 16;
3177 			continue;
3178 		}
3179 		/* allow one seek over upper bound, so we can get a correct upper_bound_sample for streams with unknown total_samples */
3180 		first_seek = false;
3181 
3182 		/* make sure we are not seeking in corrupted stream */
3183 		if (this_frame_sample < lower_bound_sample) {
3184 			decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3185 			return false;
3186 		}
3187 
3188 		/* we need to narrow the search */
3189 		if(target_sample < this_frame_sample) {
3190 			upper_bound_sample = this_frame_sample + decoder->private_->last_frame.header.blocksize;
3191 /*@@@@@@ what will decode position be if at end of stream? */
3192 			if(!FLAC__stream_decoder_get_decode_position(decoder, &upper_bound)) {
3193 				decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3194 				return false;
3195 			}
3196 			approx_bytes_per_frame = (unsigned)(2 * (upper_bound - pos) / 3 + 16);
3197 		}
3198 		else { /* target_sample >= this_frame_sample + this frame's blocksize */
3199 			lower_bound_sample = this_frame_sample + decoder->private_->last_frame.header.blocksize;
3200 			if(!FLAC__stream_decoder_get_decode_position(decoder, &lower_bound)) {
3201 				decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3202 				return false;
3203 			}
3204 			approx_bytes_per_frame = (unsigned)(2 * (lower_bound - pos) / 3 + 16);
3205 		}
3206 	}
3207 
3208 	return true;
3209 }
3210 
3211 #if FLAC__HAS_OGG
seek_to_absolute_sample_ogg_(FLAC__StreamDecoder * decoder,FLAC__uint64 stream_length,FLAC__uint64 target_sample)3212 FLAC__bool seek_to_absolute_sample_ogg_(FLAC__StreamDecoder *decoder, FLAC__uint64 stream_length, FLAC__uint64 target_sample)
3213 {
3214 	FLAC__uint64 left_pos = 0, right_pos = stream_length;
3215 	FLAC__uint64 left_sample = 0, right_sample = FLAC__stream_decoder_get_total_samples(decoder);
3216 	FLAC__uint64 this_frame_sample = (FLAC__uint64)0 - 1;
3217 	FLAC__uint64 pos = 0; /* only initialized to avoid compiler warning */
3218 	FLAC__bool did_a_seek;
3219 	unsigned iteration = 0;
3220 
3221 	/* In the first iterations, we will calculate the target byte position
3222 	 * by the distance from the target sample to left_sample and
3223 	 * right_sample (let's call it "proportional search").  After that, we
3224 	 * will switch to binary search.
3225 	 */
3226 	unsigned BINARY_SEARCH_AFTER_ITERATION = 2;
3227 
3228 	/* We will switch to a linear search once our current sample is less
3229 	 * than this number of samples ahead of the target sample
3230 	 */
3231 	static const FLAC__uint64 LINEAR_SEARCH_WITHIN_SAMPLES = FLAC__MAX_BLOCK_SIZE * 2;
3232 
3233 	/* If the total number of samples is unknown, use a large value, and
3234 	 * force binary search immediately.
3235 	 */
3236 	if(right_sample == 0) {
3237 		right_sample = (FLAC__uint64)(-1);
3238 		BINARY_SEARCH_AFTER_ITERATION = 0;
3239 	}
3240 
3241 	decoder->private_->target_sample = target_sample;
3242 	for( ; ; iteration++) {
3243 		if (iteration == 0 || this_frame_sample > target_sample || target_sample - this_frame_sample > LINEAR_SEARCH_WITHIN_SAMPLES) {
3244 			if (iteration >= BINARY_SEARCH_AFTER_ITERATION) {
3245 				pos = (right_pos + left_pos) / 2;
3246 			}
3247 			else {
3248 #ifndef FLAC__INTEGER_ONLY_LIBRARY
3249 				pos = (FLAC__uint64)((FLAC__double)(target_sample - left_sample) / (FLAC__double)(right_sample - left_sample) * (FLAC__double)(right_pos - left_pos));
3250 #else
3251 				/* a little less accurate: */
3252 				if ((target_sample-left_sample <= 0xffffffff) && (right_pos-left_pos <= 0xffffffff))
3253 					pos = (FLAC__int64)(((target_sample-left_sample) * (right_pos-left_pos)) / (right_sample-left_sample));
3254 				else /* @@@ WATCHOUT, ~2TB limit */
3255 					pos = (FLAC__int64)((((target_sample-left_sample)>>8) * ((right_pos-left_pos)>>8)) / ((right_sample-left_sample)>>16));
3256 #endif
3257 				/* @@@ TODO: might want to limit pos to some distance
3258 				 * before EOF, to make sure we land before the last frame,
3259 				 * thereby getting a this_frame_sample and so having a better
3260 				 * estimate.
3261 				 */
3262 			}
3263 
3264 			/* physical seek */
3265 			if(decoder->private_->seek_callback((FLAC__StreamDecoder*)decoder, (FLAC__uint64)pos, decoder->private_->client_data) != FLAC__STREAM_DECODER_SEEK_STATUS_OK) {
3266 				decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3267 				return false;
3268 			}
3269 			if(!FLAC__stream_decoder_flush(decoder)) {
3270 				/* above call sets the state for us */
3271 				return false;
3272 			}
3273 			did_a_seek = true;
3274 		}
3275 		else
3276 			did_a_seek = false;
3277 
3278 		decoder->private_->got_a_frame = false;
3279 		if(!FLAC__stream_decoder_process_single(decoder)) {
3280 			decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3281 			return false;
3282 		}
3283 		if(!decoder->private_->got_a_frame) {
3284 			if(did_a_seek) {
3285 				/* this can happen if we seek to a point after the last frame; we drop
3286 				 * to binary search right away in this case to avoid any wasted
3287 				 * iterations of proportional search.
3288 				 */
3289 				right_pos = pos;
3290 				BINARY_SEARCH_AFTER_ITERATION = 0;
3291 			}
3292 			else {
3293 				/* this can probably only happen if total_samples is unknown and the
3294 				 * target_sample is past the end of the stream
3295 				 */
3296 				decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3297 				return false;
3298 			}
3299 		}
3300 		/* our write callback will change the state when it gets to the target frame */
3301 		else if(!decoder->private_->is_seeking) {
3302 			break;
3303 		}
3304 		else {
3305 			this_frame_sample = decoder->private_->last_frame.header.number.sample_number;
3306 			FLAC__ASSERT(decoder->private_->last_frame.header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER);
3307 
3308 			if (did_a_seek) {
3309 				if (this_frame_sample <= target_sample) {
3310 					/* The 'equal' case should not happen, since
3311 					 * FLAC__stream_decoder_process_single()
3312 					 * should recognize that it has hit the
3313 					 * target sample and we would exit through
3314 					 * the 'break' above.
3315 					 */
3316 					FLAC__ASSERT(this_frame_sample != target_sample);
3317 
3318 					left_sample = this_frame_sample;
3319 					/* sanity check to avoid infinite loop */
3320 					if (left_pos == pos) {
3321 						decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3322 						return false;
3323 					}
3324 					left_pos = pos;
3325 				}
3326 				else if(this_frame_sample > target_sample) {
3327 					right_sample = this_frame_sample;
3328 					/* sanity check to avoid infinite loop */
3329 					if (right_pos == pos) {
3330 						decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
3331 						return false;
3332 					}
3333 					right_pos = pos;
3334 				}
3335 			}
3336 		}
3337 	}
3338 
3339 	return true;
3340 }
3341 #endif
3342 
file_read_callback_(const FLAC__StreamDecoder * decoder,FLAC__byte buffer[],size_t * bytes,void * client_data)3343 FLAC__StreamDecoderReadStatus file_read_callback_(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes, void *client_data)
3344 {
3345 	(void)client_data;
3346 
3347 	if(*bytes > 0) {
3348 		*bytes = fread(buffer, sizeof(FLAC__byte), *bytes, decoder->private_->file);
3349 		if(ferror(decoder->private_->file))
3350 			return FLAC__STREAM_DECODER_READ_STATUS_ABORT;
3351 		else if(*bytes == 0)
3352 			return FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM;
3353 		else
3354 			return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
3355 	}
3356 	else
3357 		return FLAC__STREAM_DECODER_READ_STATUS_ABORT; /* abort to avoid a deadlock */
3358 }
3359 
file_seek_callback_(const FLAC__StreamDecoder * decoder,FLAC__uint64 absolute_byte_offset,void * client_data)3360 FLAC__StreamDecoderSeekStatus file_seek_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 absolute_byte_offset, void *client_data)
3361 {
3362 	(void)client_data;
3363 
3364 	if(decoder->private_->file == stdin)
3365 		return FLAC__STREAM_DECODER_SEEK_STATUS_UNSUPPORTED;
3366 	else if(fseeko(decoder->private_->file, (FLAC__off_t)absolute_byte_offset, SEEK_SET) < 0)
3367 		return FLAC__STREAM_DECODER_SEEK_STATUS_ERROR;
3368 	else
3369 		return FLAC__STREAM_DECODER_SEEK_STATUS_OK;
3370 }
3371 
file_tell_callback_(const FLAC__StreamDecoder * decoder,FLAC__uint64 * absolute_byte_offset,void * client_data)3372 FLAC__StreamDecoderTellStatus file_tell_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 *absolute_byte_offset, void *client_data)
3373 {
3374 	FLAC__off_t pos;
3375 	(void)client_data;
3376 
3377 	if(decoder->private_->file == stdin)
3378 		return FLAC__STREAM_DECODER_TELL_STATUS_UNSUPPORTED;
3379 	else if((pos = ftello(decoder->private_->file)) < 0)
3380 		return FLAC__STREAM_DECODER_TELL_STATUS_ERROR;
3381 	else {
3382 		*absolute_byte_offset = (FLAC__uint64)pos;
3383 		return FLAC__STREAM_DECODER_TELL_STATUS_OK;
3384 	}
3385 }
3386 
file_length_callback_(const FLAC__StreamDecoder * decoder,FLAC__uint64 * stream_length,void * client_data)3387 FLAC__StreamDecoderLengthStatus file_length_callback_(const FLAC__StreamDecoder *decoder, FLAC__uint64 *stream_length, void *client_data)
3388 {
3389 	struct flac_stat_s filestats;
3390 	(void)client_data;
3391 
3392 	if(decoder->private_->file == stdin)
3393 		return FLAC__STREAM_DECODER_LENGTH_STATUS_UNSUPPORTED;
3394 	else if(flac_fstat(fileno(decoder->private_->file), &filestats) != 0)
3395 		return FLAC__STREAM_DECODER_LENGTH_STATUS_ERROR;
3396 	else {
3397 		*stream_length = (FLAC__uint64)filestats.st_size;
3398 		return FLAC__STREAM_DECODER_LENGTH_STATUS_OK;
3399 	}
3400 }
3401 
file_eof_callback_(const FLAC__StreamDecoder * decoder,void * client_data)3402 FLAC__bool file_eof_callback_(const FLAC__StreamDecoder *decoder, void *client_data)
3403 {
3404 	(void)client_data;
3405 
3406 	return feof(decoder->private_->file)? true : false;
3407 }
3408