[libsigrok.git] / src / input / wav.c

/*
 * This file is part of the libsigrok project.
 *
 * Copyright (C) 2013 Bert Vermeulen <bert@biot.com>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <fcntl.h>
#include <ctype.h>
#include <string.h>
#include <stdint.h>
#include <libsigrok/libsigrok.h>
#include "libsigrok-internal.h"

#define LOG_PREFIX "input/wav"

/* How many bytes at a time to process and send to the session bus. */
#define CHUNK_SIZE 4096

/* Minimum size of header + 1 8-bit mono PCM sample. */
#define MIN_DATA_CHUNK_OFFSET    45

/* Expect to find the "data" chunk within this offset from the start. */
#define MAX_DATA_CHUNK_OFFSET    256

#define WAVE_FORMAT_PCM_         0x0001
#define WAVE_FORMAT_IEEE_FLOAT_  0x0003
#define WAVE_FORMAT_EXTENSIBLE_  0xfffe

struct context {
	gboolean started;
	int fmt_code;
	uint64_t samplerate;
	int samplesize;
	int num_channels;
	int unitsize;
	gboolean found_data;
};

static int parse_wav_header(GString *buf, struct context *inc)
{
	uint64_t samplerate;
	unsigned int fmt_code, samplesize, num_channels, unitsize;

	if (buf->len < MIN_DATA_CHUNK_OFFSET)
		return SR_ERR_NA;

	fmt_code = RL16(buf->str + 20);
	samplerate = RL32(buf->str + 24);

	samplesize = RL16(buf->str + 32);
	num_channels = RL16(buf->str + 22);
	if (num_channels == 0)
		return SR_ERR;
	unitsize = samplesize / num_channels;
	if (unitsize != 1 && unitsize != 2 && unitsize != 4) {
		sr_err("Only 8, 16 or 32 bits per sample supported.");
		return SR_ERR_DATA;
	}

	if (fmt_code == WAVE_FORMAT_PCM_) {
	} else if (fmt_code == WAVE_FORMAT_IEEE_FLOAT_) {
		if (unitsize != 4) {
			sr_err("only 32-bit floats supported.");
			return SR_ERR_DATA;
		}
	} else if (fmt_code == WAVE_FORMAT_EXTENSIBLE_) {
		if (buf->len < 70)
			/* Not enough for extensible header and next chunk. */
			return SR_ERR_NA;

		if (RL16(buf->str + 16) != 40) {
			sr_err("WAV extensible format chunk must be 40 bytes.");
			return SR_ERR;
		}
		if (RL16(buf->str + 36) != 22) {
			sr_err("WAV extension must be 22 bytes.");
			return SR_ERR;
		}
		if (RL16(buf->str + 34) != RL16(buf->str + 38)) {
			sr_err("Reduced valid bits per sample not supported.");
			return SR_ERR_DATA;
		}
		/* Real format code is the first two bytes of the GUID. */
		fmt_code = RL16(buf->str + 44);
		if (fmt_code != WAVE_FORMAT_PCM_ && fmt_code != WAVE_FORMAT_IEEE_FLOAT_) {
			sr_err("Only PCM and floating point samples are supported.");
			return SR_ERR_DATA;
		}
		if (fmt_code == WAVE_FORMAT_IEEE_FLOAT_ && unitsize != 4) {
			sr_err("only 32-bit floats supported.");
			return SR_ERR_DATA;
		}
	} else {
		sr_err("Only PCM and floating point samples are supported.");
		return SR_ERR_DATA;
	}

	if (inc) {
		inc->fmt_code = fmt_code;
		inc->samplerate = samplerate;
		inc->samplesize = samplesize;
		inc->num_channels = num_channels;
		inc->unitsize = unitsize;
		inc->found_data = FALSE;
	}

	return SR_OK;
}

static int format_match(GHashTable *metadata)
{
	GString *buf;
	int ret;

	buf = g_hash_table_lookup(metadata, GINT_TO_POINTER(SR_INPUT_META_HEADER));
	if (strncmp(buf->str, "RIFF", 4))
		return SR_ERR;
	if (strncmp(buf->str + 8, "WAVE", 4))
		return SR_ERR;
	if (strncmp(buf->str + 12, "fmt ", 4))
		return SR_ERR;
	/*
	 * Only gets called when we already know this is a WAV file, so
	 * this parser can log error messages.
	 */
	if ((ret = parse_wav_header(buf, NULL)) != SR_OK)
		return ret;

	return SR_OK;
}

static int init(struct sr_input *in, GHashTable *options)
{
	(void)options;

	in->sdi = g_malloc0(sizeof(struct sr_dev_inst));
	in->priv = g_malloc0(sizeof(struct context));

	return SR_OK;
}

static int find_data_chunk(GString *buf, int initial_offset)
{
	unsigned int offset, i;

	offset = initial_offset;
	while (offset < MIN(MAX_DATA_CHUNK_OFFSET, buf->len)) {
		if (!memcmp(buf->str + offset, "data", 4))
			/* Skip into the samples. */
			return offset + 8;
		for (i = 0; i < 4; i++) {
			if (!isalnum(buf->str[offset + i])
					&& !isblank(buf->str[offset + i]))
				/* Doesn't look like a chunk ID. */
				return -1;
		}
		/* Skip past this chunk. */
		offset += 8 + RL32(buf->str + offset + 4);
	}

	return offset;
}

static void send_chunk(const struct sr_input *in, int offset, int num_samples)
{
	struct sr_datafeed_packet packet;
	struct sr_datafeed_analog analog;
	struct context *inc;
	float fdata[CHUNK_SIZE];
	uint64_t sample;
	int total_samples, samplenum;
	char *s, *d;

	inc = in->priv;

	s = in->buf->str + offset;
	d = (char *)fdata;
	memset(fdata, 0, CHUNK_SIZE);
	total_samples = num_samples * inc->num_channels;
	for (samplenum = 0; samplenum < total_samples; samplenum++) {
		if (inc->fmt_code == WAVE_FORMAT_PCM_) {
			sample = 0;
			memcpy(&sample, s, inc->unitsize);
			switch (inc->samplesize) {
			case 1:
				/* 8-bit PCM samples are unsigned. */
				fdata[samplenum] = (uint8_t)sample / (float)255;
				break;
			case 2:
				fdata[samplenum] = RL16S(&sample) / (float)INT16_MAX;
				break;
			case 4:
				fdata[samplenum] = RL32S(&sample) / (float)INT32_MAX;
				break;
			}
		} else {
			/* BINARY32 float */
#ifdef WORDS_BIGENDIAN
			int i;
			for (i = 0; i < inc->unitsize; i++)
				d[i] = s[inc->unitsize - 1 - i];
#else
			memcpy(d, s, inc->unitsize);
#endif
		}
		s += inc->unitsize;
		d += inc->unitsize;
	}
	packet.type = SR_DF_ANALOG;
	packet.payload = &analog;
	analog.channels = in->sdi->channels;
	analog.num_samples = num_samples;
	analog.mq = 0;
	analog.mqflags = 0;
	analog.unit = 0;
	analog.data = fdata;
	sr_session_send(in->sdi, &packet);
}

static int process_buffer(struct sr_input *in)
{
	struct context *inc;
	struct sr_datafeed_packet packet;
	struct sr_datafeed_meta meta;
	struct sr_config *src;
	int offset, chunk_samples, total_samples, processed, max_chunk_samples;
	int num_samples, i;
	char channelname[8];

	inc = in->priv;
	if (!inc->started) {
		for (i = 0; i < inc->num_channels; i++) {
			snprintf(channelname, 8, "CH%d", i + 1);
			sr_channel_new(in->sdi, i, SR_CHANNEL_ANALOG, TRUE, channelname);
		}

		std_session_send_df_header(in->sdi, LOG_PREFIX);

		packet.type = SR_DF_META;
		packet.payload = &meta;
		src = sr_config_new(SR_CONF_SAMPLERATE, g_variant_new_uint64(inc->samplerate));
		meta.config = g_slist_append(NULL, src);
		sr_session_send(in->sdi, &packet);
		sr_config_free(src);

		inc->started = TRUE;
	}

	if (!inc->found_data) {
		/* Skip past size of 'fmt ' chunk. */
		i = 20 + RL32(in->buf->str + 16);
		offset = find_data_chunk(in->buf, i);
		if (offset < 0) {
			if (in->buf->len > MAX_DATA_CHUNK_OFFSET) {
				sr_err("Couldn't find data chunk.");
				return SR_ERR;
			}
		}
		inc->found_data = TRUE;
	} else
		offset = 0;

	/* Round off up to the last channels * unitsize boundary. */
	chunk_samples = (in->buf->len - offset) / inc->num_channels / inc->unitsize;
	max_chunk_samples = CHUNK_SIZE / inc->num_channels / inc->unitsize;
	processed = 0;
	total_samples = chunk_samples;
	while (processed < total_samples) {
		if (chunk_samples > max_chunk_samples)
			num_samples = max_chunk_samples;
		else
			num_samples = chunk_samples;
		send_chunk(in, offset, num_samples);
		offset += num_samples * inc->unitsize;
		chunk_samples -= num_samples;
		processed += num_samples;
	}

	if ((unsigned int)offset < in->buf->len) {
		/*
		 * The incoming buffer wasn't processed completely. Stash
		 * the leftover data for next time.
		 */
		g_string_erase(in->buf, 0, offset);
	} else
		g_string_truncate(in->buf, 0);

	return SR_OK;
}

static int receive(struct sr_input *in, GString *buf)
{
	struct context *inc;
	int ret;

	g_string_append_len(in->buf, buf->str, buf->len);

	if (in->buf->len < MIN_DATA_CHUNK_OFFSET) {
		/*
		 * Don't even try until there's enough room
		 * for the data segment to start.
		 */
		return SR_OK;
	}

	inc = in->priv;
	if (!in->sdi_ready) {
		if ((ret = parse_wav_header(in->buf, inc)) == SR_ERR_NA)
			/* Not enough data yet. */
			return SR_OK;
		else if (ret != SR_OK)
			return ret;

		/* sdi is ready, notify frontend. */
		in->sdi_ready = TRUE;
		return SR_OK;
	}

	ret = process_buffer(in);

	return ret;
}

static int end(struct sr_input *in)
{
	struct sr_datafeed_packet packet;
	struct context *inc;
	int ret;

	if (in->sdi_ready)
		ret = process_buffer(in);
	else
		ret = SR_OK;

	inc = in->priv;
	if (inc->started) {
		packet.type = SR_DF_END;
		sr_session_send(in->sdi, &packet);
	}

	return ret;
}

SR_PRIV struct sr_input_module input_wav = {
	.id = "wav",
	.name = "WAV",
	.desc = "WAV file",
	.exts = (const char*[]){"wav", NULL},
	.metadata = { SR_INPUT_META_HEADER | SR_INPUT_META_REQUIRED },
	.format_match = format_match,
	.init = init,
	.receive = receive,
	.end = end,
};
Commit	Line	Data
1d36b4d2	1	/*
50985c20	2	* This file is part of the libsigrok project.
1d36b4d2 BV	3	*
	4	* Copyright (C) 2013 Bert Vermeulen <bert@biot.com>
	5	*
	6	* This program is free software: you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation, either version 3 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program. If not, see <http://www.gnu.org/licenses/>.
	18	*/
	19
	20	#include <sys/types.h>
	21	#include <sys/stat.h>
	22	#include <unistd.h>
	23	#include <fcntl.h>
cb41a838	24	#include <ctype.h>
1d36b4d2	25	#include <string.h>
962d4344	26	#include <stdint.h>
c1aae900	27	#include <libsigrok/libsigrok.h>
1d36b4d2 BV	28	#include "libsigrok-internal.h"
1d36b4d2 BV	29
3544f848	30	#define LOG_PREFIX "input/wav"
1d36b4d2	31
cb41a838	32	/* How many bytes at a time to process and send to the session bus. */
1d36b4d2	33	#define CHUNK_SIZE 4096
17bfaca6 BV	34
	35	/* Minimum size of header + 1 8-bit mono PCM sample. */
	36	#define MIN_DATA_CHUNK_OFFSET 45
	37
cb41a838 BV	38	/* Expect to find the "data" chunk within this offset from the start. */
	39	#define MAX_DATA_CHUNK_OFFSET 256
	40
76598cda UH	41	#define WAVE_FORMAT_PCM_ 0x0001
	42	#define WAVE_FORMAT_IEEE_FLOAT_ 0x0003
	43	#define WAVE_FORMAT_EXTENSIBLE_ 0xfffe
1d36b4d2 BV	44
1d36b4d2 BV	45	struct context {
d0181813	46	gboolean started;
17bfaca6	47	int fmt_code;
1d36b4d2 BV	48	uint64_t samplerate;
	49	int samplesize;
	50	int num_channels;
cb41a838	51	int unitsize;
17bfaca6	52	gboolean found_data;
1d36b4d2 BV	53	};
1d36b4d2 BV	54
17bfaca6	55	static int parse_wav_header(GString buf, struct context inc)
1d36b4d2	56	{
17bfaca6	57	uint64_t samplerate;
cbd9e6e9	58	unsigned int fmt_code, samplesize, num_channels, unitsize;
1d36b4d2	59
cbd9e6e9	60	if (buf->len < MIN_DATA_CHUNK_OFFSET)
d0181813	61	return SR_ERR_NA;
1d36b4d2	62
962d4344 BV	63	fmt_code = RL16(buf->str + 20);
962d4344 BV	64	samplerate = RL32(buf->str + 24);
cbd9e6e9	65
962d4344 BV	66	samplesize = RL16(buf->str + 32);
962d4344 BV	67	num_channels = RL16(buf->str + 22);
cbd9e6e9 BV	68	if (num_channels == 0)
cbd9e6e9 BV	69	return SR_ERR;
17bfaca6	70	unitsize = samplesize / num_channels;
e8779db7 BV	71	if (unitsize != 1 && unitsize != 2 && unitsize != 4) {
	72	sr_err("Only 8, 16 or 32 bits per sample supported.");
	73	return SR_ERR_DATA;
	74	}
	75
76598cda UH	76	if (fmt_code == WAVE_FORMAT_PCM_) {
76598cda UH	77	} else if (fmt_code == WAVE_FORMAT_IEEE_FLOAT_) {
17bfaca6 BV	78	if (unitsize != 4) {
17bfaca6 BV	79	sr_err("only 32-bit floats supported.");
4f979115	80	return SR_ERR_DATA;
17bfaca6	81	}
76598cda	82	} else if (fmt_code == WAVE_FORMAT_EXTENSIBLE_) {
cbd9e6e9 BV	83	if (buf->len < 70)
cbd9e6e9 BV	84	/* Not enough for extensible header and next chunk. */
d0181813	85	return SR_ERR_NA;
cbd9e6e9 BV	86
	87	if (RL16(buf->str + 16) != 40) {
	88	sr_err("WAV extensible format chunk must be 40 bytes.");
	89	return SR_ERR;
	90	}
	91	if (RL16(buf->str + 36) != 22) {
	92	sr_err("WAV extension must be 22 bytes.");
	93	return SR_ERR;
	94	}
	95	if (RL16(buf->str + 34) != RL16(buf->str + 38)) {
	96	sr_err("Reduced valid bits per sample not supported.");
4f979115	97	return SR_ERR_DATA;
cbd9e6e9 BV	98	}
	99	/* Real format code is the first two bytes of the GUID. */
	100	fmt_code = RL16(buf->str + 44);
76598cda	101	if (fmt_code != WAVE_FORMAT_PCM_ && fmt_code != WAVE_FORMAT_IEEE_FLOAT_) {
cbd9e6e9	102	sr_err("Only PCM and floating point samples are supported.");
4f979115	103	return SR_ERR_DATA;
cbd9e6e9	104	}
76598cda	105	if (fmt_code == WAVE_FORMAT_IEEE_FLOAT_ && unitsize != 4) {
28d9df72 MC	106	sr_err("only 32-bit floats supported.");
	107	return SR_ERR_DATA;
	108	}
17bfaca6 BV	109	} else {
17bfaca6 BV	110	sr_err("Only PCM and floating point samples are supported.");
4f979115	111	return SR_ERR_DATA;
17bfaca6	112	}
1d36b4d2	113
17bfaca6 BV	114	if (inc) {
	115	inc->fmt_code = fmt_code;
	116	inc->samplerate = samplerate;
	117	inc->samplesize = samplesize;
	118	inc->num_channels = num_channels;
	119	inc->unitsize = unitsize;
	120	inc->found_data = FALSE;
	121	}
1d36b4d2 BV	122
	123	return SR_OK;
	124	}
	125
17bfaca6	126	static int format_match(GHashTable *metadata)
1d36b4d2	127	{
17bfaca6	128	GString *buf;
4f979115	129	int ret;
1d36b4d2	130
17bfaca6 BV	131	buf = g_hash_table_lookup(metadata, GINT_TO_POINTER(SR_INPUT_META_HEADER));
17bfaca6 BV	132	if (strncmp(buf->str, "RIFF", 4))
4f979115	133	return SR_ERR;
17bfaca6	134	if (strncmp(buf->str + 8, "WAVE", 4))
4f979115	135	return SR_ERR;
17bfaca6	136	if (strncmp(buf->str + 12, "fmt ", 4))
4f979115	137	return SR_ERR;
17bfaca6 BV	138	/*
	139	* Only gets called when we already know this is a WAV file, so
	140	* this parser can log error messages.
	141	*/
4f979115 BV	142	if ((ret = parse_wav_header(buf, NULL)) != SR_OK)
4f979115 BV	143	return ret;
1d36b4d2	144
4f979115	145	return SR_OK;
1d36b4d2 BV	146	}
1d36b4d2 BV	147
17bfaca6	148	static int init(struct sr_input in, GHashTable options)
1d36b4d2	149	{
17bfaca6	150	(void)options;
1d36b4d2	151
aac29cc1	152	in->sdi = g_malloc0(sizeof(struct sr_dev_inst));
d0181813	153	in->priv = g_malloc0(sizeof(struct context));
1d36b4d2 BV	154
	155	return SR_OK;
	156	}
	157
17bfaca6	158	static int find_data_chunk(GString *buf, int initial_offset)
cb41a838	159	{
17bfaca6	160	unsigned int offset, i;
cb41a838 BV	161
cb41a838 BV	162	offset = initial_offset;
0c5f2abc	163	while (offset < MIN(MAX_DATA_CHUNK_OFFSET, buf->len)) {
17bfaca6	164	if (!memcmp(buf->str + offset, "data", 4))
cb41a838 BV	165	/* Skip into the samples. */
	166	return offset + 8;
	167	for (i = 0; i < 4; i++) {
94b138a3	168	if (!isalnum(buf->str[offset + i])
17bfaca6	169	&& !isblank(buf->str[offset + i]))
cb41a838 BV	170	/* Doesn't look like a chunk ID. */
	171	return -1;
	172	}
	173	/* Skip past this chunk. */
962d4344	174	offset += 8 + RL32(buf->str + offset + 4);
cb41a838 BV	175	}
	176
	177	return offset;
	178	}
	179
17bfaca6 BV	180	static void send_chunk(const struct sr_input *in, int offset, int num_samples)
	181	{
	182	struct sr_datafeed_packet packet;
	183	struct sr_datafeed_analog analog;
	184	struct context *inc;
	185	float fdata[CHUNK_SIZE];
	186	uint64_t sample;
	187	int total_samples, samplenum;
	188	char s, d;
1d36b4d2	189
7db06394	190	inc = in->priv;
17bfaca6 BV	191
	192	s = in->buf->str + offset;
	193	d = (char *)fdata;
cb41a838	194	memset(fdata, 0, CHUNK_SIZE);
17bfaca6 BV	195	total_samples = num_samples * inc->num_channels;
17bfaca6 BV	196	for (samplenum = 0; samplenum < total_samples; samplenum++) {
76598cda	197	if (inc->fmt_code == WAVE_FORMAT_PCM_) {
17bfaca6 BV	198	sample = 0;
	199	memcpy(&sample, s, inc->unitsize);
	200	switch (inc->samplesize) {
	201	case 1:
	202	/* 8-bit PCM samples are unsigned. */
962d4344	203	fdata[samplenum] = (uint8_t)sample / (float)255;
17bfaca6 BV	204	break;
17bfaca6 BV	205	case 2:
962d4344	206	fdata[samplenum] = RL16S(&sample) / (float)INT16_MAX;
17bfaca6 BV	207	break;
17bfaca6 BV	208	case 4:
962d4344	209	fdata[samplenum] = RL32S(&sample) / (float)INT32_MAX;
17bfaca6 BV	210	break;
	211	}
	212	} else {
	213	/* BINARY32 float */
cb41a838	214	#ifdef WORDS_BIGENDIAN
28d9df72	215	int i;
17bfaca6	216	for (i = 0; i < inc->unitsize; i++)
28d9df72	217	d[i] = s[inc->unitsize - 1 - i];
cb41a838	218	#else
17bfaca6	219	memcpy(d, s, inc->unitsize);
cb41a838	220	#endif
1d36b4d2	221	}
17bfaca6 BV	222	s += inc->unitsize;
	223	d += inc->unitsize;
	224	}
	225	packet.type = SR_DF_ANALOG;
	226	packet.payload = &analog;
	227	analog.channels = in->sdi->channels;
	228	analog.num_samples = num_samples;
	229	analog.mq = 0;
	230	analog.mqflags = 0;
	231	analog.unit = 0;
	232	analog.data = fdata;
	233	sr_session_send(in->sdi, &packet);
	234	}
	235
7066fd46	236	static int process_buffer(struct sr_input *in)
17bfaca6	237	{
7066fd46	238	struct context *inc;
d0181813 BV	239	struct sr_datafeed_packet packet;
d0181813 BV	240	struct sr_datafeed_meta meta;
d0181813	241	struct sr_config *src;
d0181813	242	int offset, chunk_samples, total_samples, processed, max_chunk_samples;
7066fd46	243	int num_samples, i;
d0181813	244	char channelname[8];
17bfaca6	245
d0181813	246	inc = in->priv;
d0181813 BV	247	if (!inc->started) {
	248	for (i = 0; i < inc->num_channels; i++) {
	249	snprintf(channelname, 8, "CH%d", i + 1);
5e23fcab	250	sr_channel_new(in->sdi, i, SR_CHANNEL_ANALOG, TRUE, channelname);
17bfaca6	251	}
d0181813 BV	252
	253	std_session_send_df_header(in->sdi, LOG_PREFIX);
	254
	255	packet.type = SR_DF_META;
	256	packet.payload = &meta;
	257	src = sr_config_new(SR_CONF_SAMPLERATE, g_variant_new_uint64(inc->samplerate));
	258	meta.config = g_slist_append(NULL, src);
	259	sr_session_send(in->sdi, &packet);
	260	sr_config_free(src);
	261
	262	inc->started = TRUE;
17bfaca6	263	}
17bfaca6 BV	264
	265	if (!inc->found_data) {
	266	/* Skip past size of 'fmt ' chunk. */
962d4344	267	i = 20 + RL32(in->buf->str + 16);
17bfaca6 BV	268	offset = find_data_chunk(in->buf, i);
	269	if (offset < 0) {
	270	if (in->buf->len > MAX_DATA_CHUNK_OFFSET) {
	271	sr_err("Couldn't find data chunk.");
	272	return SR_ERR;
	273	}
	274	}
	275	inc->found_data = TRUE;
	276	} else
	277	offset = 0;
	278
	279	/* Round off up to the last channels * unitsize boundary. */
	280	chunk_samples = (in->buf->len - offset) / inc->num_channels / inc->unitsize;
	281	max_chunk_samples = CHUNK_SIZE / inc->num_channels / inc->unitsize;
	282	processed = 0;
	283	total_samples = chunk_samples;
	284	while (processed < total_samples) {
	285	if (chunk_samples > max_chunk_samples)
	286	num_samples = max_chunk_samples;
	287	else
	288	num_samples = chunk_samples;
	289	send_chunk(in, offset, num_samples);
	290	offset += num_samples * inc->unitsize;
	291	chunk_samples -= num_samples;
	292	processed += num_samples;
	293	}
	294
	295	if ((unsigned int)offset < in->buf->len) {
	296	/*
	297	* The incoming buffer wasn't processed completely. Stash
	298	* the leftover data for next time.
	299	*/
	300	g_string_erase(in->buf, 0, offset);
	301	} else
	302	g_string_truncate(in->buf, 0);
1d36b4d2 BV	303
	304	return SR_OK;
	305	}
	306
7066fd46 BV	307	static int receive(struct sr_input in, GString buf)
	308	{
	309	struct context *inc;
	310	int ret;
	311
	312	g_string_append_len(in->buf, buf->str, buf->len);
	313
	314	if (in->buf->len < MIN_DATA_CHUNK_OFFSET) {
	315	/*
	316	* Don't even try until there's enough room
	317	* for the data segment to start.
	318	*/
	319	return SR_OK;
	320	}
	321
	322	inc = in->priv;
	323	if (!in->sdi_ready) {
	324	if ((ret = parse_wav_header(in->buf, inc)) == SR_ERR_NA)
	325	/* Not enough data yet. */
	326	return SR_OK;
	327	else if (ret != SR_OK)
	328	return ret;
	329
	330	/* sdi is ready, notify frontend. */
	331	in->sdi_ready = TRUE;
	332	return SR_OK;
	333	}
	334
	335	ret = process_buffer(in);
	336
18078d05	337	return ret;
7066fd46 BV	338	}
	339
	340	static int end(struct sr_input *in)
7db06394	341	{
0a4d68f7	342	struct sr_datafeed_packet packet;
d0181813	343	struct context *inc;
7066fd46 BV	344	int ret;
	345
	346	if (in->sdi_ready)
	347	ret = process_buffer(in);
	348	else
	349	ret = SR_OK;
0a4d68f7	350
d0181813 BV	351	inc = in->priv;
d0181813 BV	352	if (inc->started) {
0a4d68f7 BV	353	packet.type = SR_DF_END;
0a4d68f7 BV	354	sr_session_send(in->sdi, &packet);
0a4d68f7	355	}
7db06394	356
7066fd46	357	return ret;
7db06394 BV	358	}
7db06394 BV	359
d4c93774	360	SR_PRIV struct sr_input_module input_wav = {
1d36b4d2	361	.id = "wav",
17bfaca6 BV	362	.name = "WAV",
17bfaca6 BV	363	.desc = "WAV file",
c7bc82ff	364	.exts = (const char*[]){"wav", NULL},
17bfaca6	365	.metadata = { SR_INPUT_META_HEADER \| SR_INPUT_META_REQUIRED },
1d36b4d2 BV	366	.format_match = format_match,
1d36b4d2 BV	367	.init = init,
17bfaca6	368	.receive = receive,
7066fd46	369	.end = end,
1d36b4d2	370	};