[pcsx_rearmed.git] / deps / libchdr / flac.c

/* license:BSD-3-Clause
 * copyright-holders:Aaron Giles
***************************************************************************

    flac.c

    FLAC compression wrappers

***************************************************************************/

#include <assert.h>
#include <string.h>
#include "flac.h"

/***************************************************************************
 *  FLAC DECODER
 ***************************************************************************
 */

static FLAC__StreamDecoderReadStatus flac_decoder_read_callback_static(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes, void *client_data);
FLAC__StreamDecoderReadStatus flac_decoder_read_callback(void* client_data, FLAC__byte buffer[], size_t *bytes);
static void flac_decoder_metadata_callback_static(const FLAC__StreamDecoder *decoder, const FLAC__StreamMetadata *metadata, void *client_data);
static FLAC__StreamDecoderTellStatus flac_decoder_tell_callback_static(const FLAC__StreamDecoder *decoder, FLAC__uint64 *absolute_byte_offset, void *client_data);
static FLAC__StreamDecoderWriteStatus flac_decoder_write_callback_static(const FLAC__StreamDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[], void *client_data);
FLAC__StreamDecoderWriteStatus flac_decoder_write_callback(void* client_data, const FLAC__Frame *frame, const FLAC__int32 * const buffer[]);
static void flac_decoder_error_callback_static(const FLAC__StreamDecoder *decoder, FLAC__StreamDecoderErrorStatus status, void *client_data);

/* getters (valid after reset) */
static uint32_t sample_rate(flac_decoder *decoder)  { return decoder->sample_rate; }
static uint8_t channels(flac_decoder *decoder)  { return decoder->channels; }
static uint8_t bits_per_sample(flac_decoder *decoder) { return decoder->bits_per_sample; }
static uint32_t total_samples(flac_decoder *decoder)  { return FLAC__stream_decoder_get_total_samples(decoder->decoder); }
static FLAC__StreamDecoderState state(flac_decoder *decoder) { return FLAC__stream_decoder_get_state(decoder->decoder); }
static const char *state_string(flac_decoder *decoder) { return FLAC__stream_decoder_get_resolved_state_string(decoder->decoder); }

/*-------------------------------------------------
 *  flac_decoder - constructor
 *-------------------------------------------------
 */

void flac_decoder_init(flac_decoder *decoder)
{
	decoder->decoder = FLAC__stream_decoder_new();
	decoder->sample_rate = 0;
	decoder->channels = 0;
	decoder->bits_per_sample = 0;
	decoder->compressed_offset = 0;
	decoder->compressed_start = NULL;
	decoder->compressed_length = 0;
	decoder->compressed2_start = NULL;
	decoder->compressed2_length = 0;
	decoder->uncompressed_offset = 0;
	decoder->uncompressed_length = 0;
	decoder->uncompressed_swap = 0;
}

/*-------------------------------------------------
 *  flac_decoder - destructor
 *-------------------------------------------------
 */

void flac_decoder_free(flac_decoder* decoder)
{
	if ((decoder != NULL) && (decoder->decoder != NULL))
		FLAC__stream_decoder_delete(decoder->decoder);
}

/*-------------------------------------------------
 *  reset - reset state with the original
 *  parameters
 *-------------------------------------------------
 */

static int flac_decoder_internal_reset(flac_decoder* decoder)
{
	decoder->compressed_offset = 0;
	if (FLAC__stream_decoder_init_stream(decoder->decoder,
				&flac_decoder_read_callback_static,
				NULL,
				&flac_decoder_tell_callback_static,
				NULL,
				NULL,
				&flac_decoder_write_callback_static,
				&flac_decoder_metadata_callback_static,
				&flac_decoder_error_callback_static, decoder) != FLAC__STREAM_DECODER_INIT_STATUS_OK)
		return 0;
	return FLAC__stream_decoder_process_until_end_of_metadata(decoder->decoder);
}

/*-------------------------------------------------
 *  reset - reset state with new memory parameters
 *  and a custom-generated header
 *-------------------------------------------------
 */

int flac_decoder_reset(flac_decoder* decoder, uint32_t sample_rate, uint8_t num_channels, uint32_t block_size, const void *buffer, uint32_t length)
{
	/* modify the template header with our parameters */
	static const uint8_t s_header_template[0x2a] =
	{
		0x66, 0x4C, 0x61, 0x43,                         /* +00: 'fLaC' stream header */
		0x80,                                           /* +04: metadata block type 0 (STREAMINFO), */
								/*      flagged as last block */
		0x00, 0x00, 0x22,                               /* +05: metadata block length = 0x22 */
		0x00, 0x00,                                     /* +08: minimum block size */
		0x00, 0x00,                                     /* +0A: maximum block size */
		0x00, 0x00, 0x00,                               /* +0C: minimum frame size (0 == unknown) */
		0x00, 0x00, 0x00,                               /* +0F: maximum frame size (0 == unknown) */
		0x0A, 0xC4, 0x42, 0xF0, 0x00, 0x00, 0x00, 0x00, /* +12: sample rate (0x0ac44 == 44100), */
								/*      numchannels (2), sample bits (16), */
								/*      samples in stream (0 == unknown) */
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* +1A: MD5 signature (0 == none) */
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00  /* +2A: start of stream data */
	};
	memcpy(decoder->custom_header, s_header_template, sizeof(s_header_template));
	decoder->custom_header[0x08] = decoder->custom_header[0x0a] = block_size >> 8;
	decoder->custom_header[0x09] = decoder->custom_header[0x0b] = block_size & 0xff;
	decoder->custom_header[0x12] = sample_rate >> 12;
	decoder->custom_header[0x13] = sample_rate >> 4;
	decoder->custom_header[0x14] = (sample_rate << 4) | ((num_channels - 1) << 1);

	/* configure the header ahead of the provided buffer */
	decoder->compressed_start = (const FLAC__byte *)(decoder->custom_header);
	decoder->compressed_length = sizeof(decoder->custom_header);
	decoder->compressed2_start = (const FLAC__byte *)(buffer);
	decoder->compressed2_length = length;
	return flac_decoder_internal_reset(decoder);
}

/*-------------------------------------------------
 *  decode_interleaved - decode to an interleaved
 *  sound stream
 *-------------------------------------------------
 */

int flac_decoder_decode_interleaved(flac_decoder* decoder, int16_t *samples, uint32_t num_samples, int swap_endian)
{
	/* configure the uncompressed buffer */
	memset(decoder->uncompressed_start, 0, sizeof(decoder->uncompressed_start));
	decoder->uncompressed_start[0] = samples;
	decoder->uncompressed_offset = 0;
	decoder->uncompressed_length = num_samples;
	decoder->uncompressed_swap = swap_endian;

	/* loop until we get everything we want */
	while (decoder->uncompressed_offset < decoder->uncompressed_length)
		if (!FLAC__stream_decoder_process_single(decoder->decoder))
			return 0;
	return 1;
}

#if 0
/*-------------------------------------------------
 *  decode - decode to an multiple independent
 *  data streams
 *-------------------------------------------------
 */

bool flac_decoder::decode(int16_t **samples, uint32_t num_samples, bool swap_endian)
{
	/* make sure we don't have too many channels */
	int chans = channels();
	if (chans > ARRAY_LENGTH(m_uncompressed_start))
		return false;

	/* configure the uncompressed buffer */
	memset(m_uncompressed_start, 0, sizeof(m_uncompressed_start));
	for (int curchan = 0; curchan < chans; curchan++)
		m_uncompressed_start[curchan] = samples[curchan];
	m_uncompressed_offset = 0;
	m_uncompressed_length = num_samples;
	m_uncompressed_swap = swap_endian;

	/* loop until we get everything we want */
	while (m_uncompressed_offset < m_uncompressed_length)
		if (!FLAC__stream_decoder_process_single(m_decoder))
			return false;
	return true;
}
#endif

/*-------------------------------------------------
 *  finish - finish up the decode
 *-------------------------------------------------
 */

uint32_t flac_decoder_finish(flac_decoder* decoder)
{
	/* get the final decoding position and move forward */
	FLAC__uint64 position = 0;
	FLAC__stream_decoder_get_decode_position(decoder->decoder, &position);
	FLAC__stream_decoder_finish(decoder->decoder);

	/* adjust position if we provided the header */
	if (position == 0)
		return 0;
	if (decoder->compressed_start == (const FLAC__byte *)(decoder->custom_header))
		position -= decoder->compressed_length;
	return position;
}

/*-------------------------------------------------
 *  read_callback - handle reads from the input
 *  stream
 *-------------------------------------------------
 */

#define MIN(x, y) ((x) < (y) ? (x) : (y))

FLAC__StreamDecoderReadStatus flac_decoder_read_callback_static(const FLAC__StreamDecoder *decoder, FLAC__byte buffer[], size_t *bytes, void *client_data)
{
	return flac_decoder_read_callback(client_data, buffer, bytes);
}

FLAC__StreamDecoderReadStatus flac_decoder_read_callback(void* client_data, FLAC__byte buffer[], size_t *bytes)
{
	flac_decoder* decoder = (flac_decoder*)client_data;

	uint32_t expected = *bytes;

	/* copy from primary buffer first */
	uint32_t outputpos = 0;
	if (outputpos < *bytes && decoder->compressed_offset < decoder->compressed_length)
	{
		uint32_t bytes_to_copy = MIN(*bytes - outputpos, decoder->compressed_length - decoder->compressed_offset);
		memcpy(&buffer[outputpos], decoder->compressed_start + decoder->compressed_offset, bytes_to_copy);
		outputpos += bytes_to_copy;
		decoder->compressed_offset += bytes_to_copy;
	}

	/* once we're out of that, copy from the secondary buffer */
	if (outputpos < *bytes && decoder->compressed_offset < decoder->compressed_length + decoder->compressed2_length)
	{
		uint32_t bytes_to_copy = MIN(*bytes - outputpos, decoder->compressed2_length - (decoder->compressed_offset - decoder->compressed_length));
		memcpy(&buffer[outputpos], decoder->compressed2_start + decoder->compressed_offset - decoder->compressed_length, bytes_to_copy);
		outputpos += bytes_to_copy;
		decoder->compressed_offset += bytes_to_copy;
	}
	*bytes = outputpos;

	/* return based on whether we ran out of data */
	return (*bytes < expected) ? FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM : FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
}

/*-------------------------------------------------
 *  metadata_callback - handle STREAMINFO metadata
 *-------------------------------------------------
 */

void flac_decoder_metadata_callback_static(const FLAC__StreamDecoder *decoder, const FLAC__StreamMetadata *metadata, void *client_data)
{
	flac_decoder *fldecoder;
	/* ignore all but STREAMINFO metadata */
	if (metadata->type != FLAC__METADATA_TYPE_STREAMINFO)
		return;

	/* parse out the data we care about */
	fldecoder = (flac_decoder *)(client_data);
	fldecoder->sample_rate = metadata->data.stream_info.sample_rate;
	fldecoder->bits_per_sample = metadata->data.stream_info.bits_per_sample;
	fldecoder->channels = metadata->data.stream_info.channels;
}

/*-------------------------------------------------
 *  tell_callback - handle requests to find out
 *  where in the input stream we are
 *-------------------------------------------------
 */

FLAC__StreamDecoderTellStatus flac_decoder_tell_callback_static(const FLAC__StreamDecoder *decoder, FLAC__uint64 *absolute_byte_offset, void *client_data)
{
	*absolute_byte_offset = ((flac_decoder *)client_data)->compressed_offset;
	return FLAC__STREAM_DECODER_TELL_STATUS_OK;
}

/*-------------------------------------------------
 *  write_callback - handle writes to the output
 *  stream
 *-------------------------------------------------
 */

FLAC__StreamDecoderWriteStatus flac_decoder_write_callback_static(const FLAC__StreamDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[], void *client_data)
{
	return flac_decoder_write_callback(client_data, frame, buffer);
}

FLAC__StreamDecoderWriteStatus flac_decoder_write_callback(void *client_data, const FLAC__Frame *frame, const FLAC__int32 * const buffer[])
{
	int sampnum, chan;
	int shift, blocksize;
	flac_decoder * decoder = (flac_decoder *)client_data;

	assert(frame->header.channels == channels(decoder));

	/* interleaved case */
	shift = decoder->uncompressed_swap ? 8 : 0;
	blocksize = frame->header.blocksize;
	if (decoder->uncompressed_start[1] == NULL)
	{
		int16_t *dest = decoder->uncompressed_start[0] + decoder->uncompressed_offset * frame->header.channels;
		for (sampnum = 0; sampnum < blocksize && decoder->uncompressed_offset < decoder->uncompressed_length; sampnum++, decoder->uncompressed_offset++)
			for (chan = 0; chan < frame->header.channels; chan++)
				*dest++ = (int16_t)((((uint16_t)buffer[chan][sampnum]) << shift) | (((uint16_t)buffer[chan][sampnum]) >> shift));
	}

	/* non-interleaved case */
	else
	{
		for (sampnum = 0; sampnum < blocksize && decoder->uncompressed_offset < decoder->uncompressed_length; sampnum++, decoder->uncompressed_offset++)
			for (chan = 0; chan < frame->header.channels; chan++)
				if (decoder->uncompressed_start[chan] != NULL)
					decoder->uncompressed_start[chan][decoder->uncompressed_offset] = (int16_t) ( (((uint16_t)(buffer[chan][sampnum])) << shift) | ( ((uint16_t)(buffer[chan][sampnum])) >> shift) );
	}
	return FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE;
}

/**
 * @fn  void flac_decoder::error_callback_static(const FLAC__StreamDecoder *decoder, FLAC__StreamDecoderErrorStatus status, void *client_data)
 *
 * @brief   -------------------------------------------------
 *            error_callback - handle errors (ignore them)
 *          -------------------------------------------------.
 *
 * @param   decoder             The decoder.
 * @param   status              The status.
 * @param [in,out]  client_data If non-null, information describing the client.
 */

void flac_decoder_error_callback_static(const FLAC__StreamDecoder *decoder, FLAC__StreamDecoderErrorStatus status, void *client_data)
{
}
Commit	Line	Data
9c659ffe	1	/* license:BSD-3-Clause
	2	* copyright-holders:Aaron Giles
	3	***************************************************************************
	4
	5	flac.c
	6
	7	FLAC compression wrappers
	8
	9	***************************************************************************/
	10
	11	#include <assert.h>
	12	#include <string.h>
	13	#include "flac.h"
	14
	15	/***************************************************************************
	16	* FLAC DECODER
	17	***************************************************************************
	18	*/
	19
	20	static FLAC__StreamDecoderReadStatus flac_decoder_read_callback_static(const FLAC__StreamDecoder decoder, FLAC__byte buffer[], size_t bytes, void *client_data);
	21	FLAC__StreamDecoderReadStatus flac_decoder_read_callback(void* client_data, FLAC__byte buffer[], size_t *bytes);
	22	static void flac_decoder_metadata_callback_static(const FLAC__StreamDecoder decoder, const FLAC__StreamMetadata metadata, void *client_data);
	23	static FLAC__StreamDecoderTellStatus flac_decoder_tell_callback_static(const FLAC__StreamDecoder decoder, FLAC__uint64 absolute_byte_offset, void *client_data);
	24	static FLAC__StreamDecoderWriteStatus flac_decoder_write_callback_static(const FLAC__StreamDecoder decoder, const FLAC__Frame frame, const FLAC__int32 * const buffer[], void *client_data);
	25	FLAC__StreamDecoderWriteStatus flac_decoder_write_callback(void* client_data, const FLAC__Frame frame, const FLAC__int32 const buffer[]);
	26	static void flac_decoder_error_callback_static(const FLAC__StreamDecoder decoder, FLAC__StreamDecoderErrorStatus status, void client_data);
	27
	28	/* getters (valid after reset) */
	29	static uint32_t sample_rate(flac_decoder *decoder) { return decoder->sample_rate; }
	30	static uint8_t channels(flac_decoder *decoder) { return decoder->channels; }
	31	static uint8_t bits_per_sample(flac_decoder *decoder) { return decoder->bits_per_sample; }
	32	static uint32_t total_samples(flac_decoder *decoder) { return FLAC__stream_decoder_get_total_samples(decoder->decoder); }
	33	static FLAC__StreamDecoderState state(flac_decoder *decoder) { return FLAC__stream_decoder_get_state(decoder->decoder); }
	34	static const char state_string(flac_decoder decoder) { return FLAC__stream_decoder_get_resolved_state_string(decoder->decoder); }
	35
	36	/*-------------------------------------------------
	37	* flac_decoder - constructor
	38	*-------------------------------------------------
	39	*/
	40
	41	void flac_decoder_init(flac_decoder *decoder)
	42	{
	43	decoder->decoder = FLAC__stream_decoder_new();
	44	decoder->sample_rate = 0;
	45	decoder->channels = 0;
	46	decoder->bits_per_sample = 0;
	47	decoder->compressed_offset = 0;
	48	decoder->compressed_start = NULL;
	49	decoder->compressed_length = 0;
	50	decoder->compressed2_start = NULL;
	51	decoder->compressed2_length = 0;
	52	decoder->uncompressed_offset = 0;
	53	decoder->uncompressed_length = 0;
	54	decoder->uncompressed_swap = 0;
	55	}
	56
	57	/*-------------------------------------------------
	58	* flac_decoder - destructor
	59	*-------------------------------------------------
	60	*/
	61
	62	void flac_decoder_free(flac_decoder* decoder)
	63	{
	64	if ((decoder != NULL) && (decoder->decoder != NULL))
65	FLAC__stream_decoder_delete(decoder->decoder);
66	}
67
68	/*-------------------------------------------------
69	* reset - reset state with the original
70	* parameters
71	*-------------------------------------------------
72	*/
73
74	static int flac_decoder_internal_reset(flac_decoder* decoder)
75	{
76	decoder->compressed_offset = 0;
77	if (FLAC__stream_decoder_init_stream(decoder->decoder,
78	&flac_decoder_read_callback_static,
79	NULL,
80	&flac_decoder_tell_callback_static,
81	NULL,
82	NULL,
83	&flac_decoder_write_callback_static,
84	&flac_decoder_metadata_callback_static,
85	&flac_decoder_error_callback_static, decoder) != FLAC__STREAM_DECODER_INIT_STATUS_OK)
86	return 0;
87	return FLAC__stream_decoder_process_until_end_of_metadata(decoder->decoder);
88	}
89
90	/*-------------------------------------------------
91	* reset - reset state with new memory parameters
92	* and a custom-generated header
93	*-------------------------------------------------
94	*/
95
96	int flac_decoder_reset(flac_decoder* decoder, uint32_t sample_rate, uint8_t num_channels, uint32_t block_size, const void *buffer, uint32_t length)
97	{
98	/* modify the template header with our parameters */
99	static const uint8_t s_header_template[0x2a] =
100	{
101	0x66, 0x4C, 0x61, 0x43, /* +00: 'fLaC' stream header */
102	0x80, /* +04: metadata block type 0 (STREAMINFO), */
103	/* flagged as last block */
104	0x00, 0x00, 0x22, /* +05: metadata block length = 0x22 */
105	0x00, 0x00, /* +08: minimum block size */
106	0x00, 0x00, /* +0A: maximum block size */
107	0x00, 0x00, 0x00, /* +0C: minimum frame size (0 == unknown) */
108	0x00, 0x00, 0x00, /* +0F: maximum frame size (0 == unknown) */
109	0x0A, 0xC4, 0x42, 0xF0, 0x00, 0x00, 0x00, 0x00, /* +12: sample rate (0x0ac44 == 44100), */
110	/* numchannels (2), sample bits (16), */
111	/* samples in stream (0 == unknown) */
112	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* +1A: MD5 signature (0 == none) */
113	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 /* +2A: start of stream data */
114	};
115	memcpy(decoder->custom_header, s_header_template, sizeof(s_header_template));
116	decoder->custom_header[0x08] = decoder->custom_header[0x0a] = block_size >> 8;
117	decoder->custom_header[0x09] = decoder->custom_header[0x0b] = block_size & 0xff;
118	decoder->custom_header[0x12] = sample_rate >> 12;
119	decoder->custom_header[0x13] = sample_rate >> 4;
120	decoder->custom_header[0x14] = (sample_rate << 4) \| ((num_channels - 1) << 1);
121
122	/* configure the header ahead of the provided buffer */
123	decoder->compressed_start = (const FLAC__byte *)(decoder->custom_header);
124	decoder->compressed_length = sizeof(decoder->custom_header);
125	decoder->compressed2_start = (const FLAC__byte *)(buffer);
126	decoder->compressed2_length = length;
127	return flac_decoder_internal_reset(decoder);
128	}
129
130	/*-------------------------------------------------
131	* decode_interleaved - decode to an interleaved
132	* sound stream
133	*-------------------------------------------------
134	*/
135
136	int flac_decoder_decode_interleaved(flac_decoder* decoder, int16_t *samples, uint32_t num_samples, int swap_endian)
137	{
138	/* configure the uncompressed buffer */
139	memset(decoder->uncompressed_start, 0, sizeof(decoder->uncompressed_start));
140	decoder->uncompressed_start[0] = samples;
141	decoder->uncompressed_offset = 0;
142	decoder->uncompressed_length = num_samples;
143	decoder->uncompressed_swap = swap_endian;
144
145	/* loop until we get everything we want */
146	while (decoder->uncompressed_offset < decoder->uncompressed_length)
147	if (!FLAC__stream_decoder_process_single(decoder->decoder))
148	return 0;
149	return 1;
150	}
151
152	#if 0
153	/*-------------------------------------------------
154	* decode - decode to an multiple independent
155	* data streams
156	*-------------------------------------------------
157	*/
158
159	bool flac_decoder::decode(int16_t **samples, uint32_t num_samples, bool swap_endian)
160	{
161	/* make sure we don't have too many channels */
162	int chans = channels();
163	if (chans > ARRAY_LENGTH(m_uncompressed_start))
164	return false;
165
166	/* configure the uncompressed buffer */
167	memset(m_uncompressed_start, 0, sizeof(m_uncompressed_start));
168	for (int curchan = 0; curchan < chans; curchan++)
169	m_uncompressed_start[curchan] = samples[curchan];
170	m_uncompressed_offset = 0;
171	m_uncompressed_length = num_samples;
172	m_uncompressed_swap = swap_endian;
173
174	/* loop until we get everything we want */
175	while (m_uncompressed_offset < m_uncompressed_length)
176	if (!FLAC__stream_decoder_process_single(m_decoder))
177	return false;
178	return true;
179	}
180	#endif
181
182	/*-------------------------------------------------
183	* finish - finish up the decode
184	*-------------------------------------------------
185	*/
186
187	uint32_t flac_decoder_finish(flac_decoder* decoder)
188	{
189	/* get the final decoding position and move forward */
190	FLAC__uint64 position = 0;
191	FLAC__stream_decoder_get_decode_position(decoder->decoder, &position);
192	FLAC__stream_decoder_finish(decoder->decoder);
193
194	/* adjust position if we provided the header */
195	if (position == 0)
196	return 0;
197	if (decoder->compressed_start == (const FLAC__byte *)(decoder->custom_header))
198	position -= decoder->compressed_length;
199	return position;
200	}
201
202	/*-------------------------------------------------
203	* read_callback - handle reads from the input
204	* stream
205	*-------------------------------------------------
206	*/
207
208	#define MIN(x, y) ((x) < (y) ? (x) : (y))
209
210	FLAC__StreamDecoderReadStatus flac_decoder_read_callback_static(const FLAC__StreamDecoder decoder, FLAC__byte buffer[], size_t bytes, void *client_data)
211	{
212	return flac_decoder_read_callback(client_data, buffer, bytes);
213	}
214
215	FLAC__StreamDecoderReadStatus flac_decoder_read_callback(void* client_data, FLAC__byte buffer[], size_t *bytes)
216	{
217	flac_decoder* decoder = (flac_decoder*)client_data;
218
219	uint32_t expected = *bytes;
220
221	/* copy from primary buffer first */
222	uint32_t outputpos = 0;
223	if (outputpos < *bytes && decoder->compressed_offset < decoder->compressed_length)
224	{
225	uint32_t bytes_to_copy = MIN(*bytes - outputpos, decoder->compressed_length - decoder->compressed_offset);
226	memcpy(&buffer[outputpos], decoder->compressed_start + decoder->compressed_offset, bytes_to_copy);
227	outputpos += bytes_to_copy;
228	decoder->compressed_offset += bytes_to_copy;
229	}
230
231	/* once we're out of that, copy from the secondary buffer */
232	if (outputpos < *bytes && decoder->compressed_offset < decoder->compressed_length + decoder->compressed2_length)
233	{
234	uint32_t bytes_to_copy = MIN(*bytes - outputpos, decoder->compressed2_length - (decoder->compressed_offset - decoder->compressed_length));
235	memcpy(&buffer[outputpos], decoder->compressed2_start + decoder->compressed_offset - decoder->compressed_length, bytes_to_copy);
236	outputpos += bytes_to_copy;
237	decoder->compressed_offset += bytes_to_copy;
238	}
239	*bytes = outputpos;
240
241	/* return based on whether we ran out of data */
242	return (*bytes < expected) ? FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM : FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
243	}
244
245	/*-------------------------------------------------
246	* metadata_callback - handle STREAMINFO metadata
247	*-------------------------------------------------
248	*/
249
250	void flac_decoder_metadata_callback_static(const FLAC__StreamDecoder decoder, const FLAC__StreamMetadata metadata, void *client_data)
251	{
252	flac_decoder *fldecoder;
253	/* ignore all but STREAMINFO metadata */
254	if (metadata->type != FLAC__METADATA_TYPE_STREAMINFO)
255	return;
256
257	/* parse out the data we care about */
258	fldecoder = (flac_decoder *)(client_data);
259	fldecoder->sample_rate = metadata->data.stream_info.sample_rate;
260	fldecoder->bits_per_sample = metadata->data.stream_info.bits_per_sample;
261	fldecoder->channels = metadata->data.stream_info.channels;
262	}
263
264	/*-------------------------------------------------
265	* tell_callback - handle requests to find out
266	* where in the input stream we are
267	*-------------------------------------------------
268	*/
269
270	FLAC__StreamDecoderTellStatus flac_decoder_tell_callback_static(const FLAC__StreamDecoder decoder, FLAC__uint64 absolute_byte_offset, void *client_data)
271	{
272	absolute_byte_offset = ((flac_decoder )client_data)->compressed_offset;
273	return FLAC__STREAM_DECODER_TELL_STATUS_OK;
274	}
275
276	/*-------------------------------------------------
277	* write_callback - handle writes to the output
278	* stream
279	*-------------------------------------------------
280	*/
281
282	FLAC__StreamDecoderWriteStatus flac_decoder_write_callback_static(const FLAC__StreamDecoder decoder, const FLAC__Frame frame, const FLAC__int32 * const buffer[], void *client_data)
283	{
284	return flac_decoder_write_callback(client_data, frame, buffer);
285	}
286
287	FLAC__StreamDecoderWriteStatus flac_decoder_write_callback(void client_data, const FLAC__Frame frame, const FLAC__int32 * const buffer[])
288	{
289	int sampnum, chan;
290	int shift, blocksize;
291	flac_decoder * decoder = (flac_decoder *)client_data;
292
293	assert(frame->header.channels == channels(decoder));
294
295	/* interleaved case */
296	shift = decoder->uncompressed_swap ? 8 : 0;
297	blocksize = frame->header.blocksize;
298	if (decoder->uncompressed_start[1] == NULL)
299	{
300	int16_t dest = decoder->uncompressed_start[0] + decoder->uncompressed_offset frame->header.channels;
301	for (sampnum = 0; sampnum < blocksize && decoder->uncompressed_offset < decoder->uncompressed_length; sampnum++, decoder->uncompressed_offset++)
302	for (chan = 0; chan < frame->header.channels; chan++)
303	*dest++ = (int16_t)((((uint16_t)buffer[chan][sampnum]) << shift) \| (((uint16_t)buffer[chan][sampnum]) >> shift));
304	}
305
306	/* non-interleaved case */
307	else
308	{
309	for (sampnum = 0; sampnum < blocksize && decoder->uncompressed_offset < decoder->uncompressed_length; sampnum++, decoder->uncompressed_offset++)
310	for (chan = 0; chan < frame->header.channels; chan++)
311	if (decoder->uncompressed_start[chan] != NULL)
312	decoder->uncompressed_start[chan][decoder->uncompressed_offset] = (int16_t) ( (((uint16_t)(buffer[chan][sampnum])) << shift) \| ( ((uint16_t)(buffer[chan][sampnum])) >> shift) );
313	}
314	return FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE;
315	}
316
317	/**
318	* @fn void flac_decoder::error_callback_static(const FLAC__StreamDecoder decoder, FLAC__StreamDecoderErrorStatus status, void client_data)
319	*
320	* @brief -------------------------------------------------
321	* error_callback - handle errors (ignore them)
322	* -------------------------------------------------.
323	*
324	* @param decoder The decoder.
325	* @param status The status.
326	* @param [in,out] client_data If non-null, information describing the client.
327	*/
328
329	void flac_decoder_error_callback_static(const FLAC__StreamDecoder decoder, FLAC__StreamDecoderErrorStatus status, void client_data)
330	{
331	}