[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 "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          1
#define WAVE_FORMAT_IEEE_FLOAT   3

struct context {
	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;
	int fmt_code, samplesize, num_channels, unitsize;

	if (buf->len < MIN_DATA_CHUNK_OFFSET) {
		return SR_ERR;
	}

	fmt_code = GUINT16_FROM_LE(*(uint16_t *)(buf->str + 20));
	samplerate = GUINT32_FROM_LE(*(uint32_t *)(buf->str + 24));
	samplesize = GUINT16_FROM_LE(*(uint16_t *)(buf->str + 32));
	num_channels = GUINT16_FROM_LE(*(uint16_t *)(buf->str + 22));
	/* TODO div0 */
	unitsize = samplesize / num_channels;

	if (fmt_code == WAVE_FORMAT_PCM) {
		if (samplesize != 1 && samplesize != 2 && samplesize != 4) {
			sr_err("only 8, 16 or 32 bits per sample supported.");
			return SR_ERR;
		}
	} else if (fmt_code == WAVE_FORMAT_IEEE_FLOAT) {
		if (unitsize != 4) {
			sr_err("only 32-bit floats supported.");
			return SR_ERR;
		}
	} else {
		sr_err("Only PCM and floating point samples are supported.");
		return SR_ERR;
	}

	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;

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

	return TRUE;
}

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

	in->sdi = sr_dev_inst_new(0, SR_ST_ACTIVE, NULL, NULL, NULL);

	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 (!isalpha(buf->str[offset + i])
					&& !isascii(buf->str[offset + i])
					&& !isblank(buf->str[offset + i]))
				/* Doesn't look like a chunk ID. */
				return -1;
		}
		/* Skip past this chunk. */
		offset += 8 + GUINT32_FROM_LE(*(uint32_t *)(buf->str + offset + 4));
	}

	return offset;
}

static int initial_receive(const struct sr_input *in)
{
	struct sr_datafeed_packet packet;
	struct sr_datafeed_meta meta;
	struct sr_channel *ch;
	struct sr_config *src;
	struct context *inc;
	int i;
	char channelname[8];

	if (!in->buf)
		/* Shouldn't happen. */
		return SR_ERR;

	inc = in->sdi->priv = g_malloc(sizeof(struct context));
	if (parse_wav_header(in->buf, inc) != SR_OK)
		return SR_ERR;

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

	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);

	return SR_OK;
}

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->sdi->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 / 255.0;
				break;
			case 2:
				fdata[samplenum] = GINT16_FROM_LE(sample) / 32767.0;
				break;
			case 4:
				fdata[samplenum] = GINT32_FROM_LE(sample) / 65535.0;
				break;
			}
		} else {
			/* BINARY32 float */
#ifdef WORDS_BIGENDIAN
			for (i = 0; i < inc->unitsize; i++)
				d[i] = s[inc->unitsize - 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 receive(const struct sr_input *in, GString *buf)
{
	struct sr_datafeed_packet packet;
	struct context *inc;
	int offset, chunk_samples, total_samples, processed, max_chunk_samples, num_samples, i;

	if (buf->len == 0) {
		/* End of stream. */
		packet.type = SR_DF_END;
		sr_session_send(in->sdi, &packet);
		return SR_OK;
	}

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

	if (!in->sdi->priv) {
		if (initial_receive(in) != SR_OK)
			return SR_ERR;
		if (in->buf->len < MIN_DATA_CHUNK_OFFSET) {
			/*
			 * Don't even get started until there's enough room
			 * for the data segment to start.
			 */
			return SR_OK;
		}
	}
	inc = in->sdi->priv;

	if (!inc->found_data) {
		/* Skip past size of 'fmt ' chunk. */
		i = 20 + GUINT32_FROM_LE(*(uint32_t *)(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;
}

SR_PRIV struct sr_input_module input_wav = {
	.id = "wav",
	.name = "WAV",
	.desc = "WAV file",
	.metadata = { SR_INPUT_META_HEADER | SR_INPUT_META_REQUIRED },
	.format_match = format_match,
	.init = init,
	.receive = receive,
};
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 BV	25	#include <string.h>
	26	#include "libsigrok.h"
	27	#include "libsigrok-internal.h"
	28
3544f848	29	#define LOG_PREFIX "input/wav"
1d36b4d2	30
cb41a838	31	/* How many bytes at a time to process and send to the session bus. */
1d36b4d2	32	#define CHUNK_SIZE 4096
17bfaca6 BV	33
	34	/* Minimum size of header + 1 8-bit mono PCM sample. */
	35	#define MIN_DATA_CHUNK_OFFSET 45
	36
cb41a838 BV	37	/* Expect to find the "data" chunk within this offset from the start. */
	38	#define MAX_DATA_CHUNK_OFFSET 256
	39
	40	#define WAVE_FORMAT_PCM 1
	41	#define WAVE_FORMAT_IEEE_FLOAT 3
1d36b4d2 BV	42
1d36b4d2 BV	43	struct context {
17bfaca6	44	int fmt_code;
1d36b4d2 BV	45	uint64_t samplerate;
	46	int samplesize;
	47	int num_channels;
cb41a838	48	int unitsize;
17bfaca6	49	gboolean found_data;
1d36b4d2 BV	50	};
1d36b4d2 BV	51
17bfaca6	52	static int parse_wav_header(GString buf, struct context inc)
1d36b4d2	53	{
17bfaca6 BV	54	uint64_t samplerate;
17bfaca6 BV	55	int fmt_code, samplesize, num_channels, unitsize;
1d36b4d2	56
17bfaca6	57	if (buf->len < MIN_DATA_CHUNK_OFFSET) {
1d36b4d2	58	return SR_ERR;
17bfaca6	59	}
1d36b4d2	60
17bfaca6 BV	61	fmt_code = GUINT16_FROM_LE((uint16_t )(buf->str + 20));
	62	samplerate = GUINT32_FROM_LE((uint32_t )(buf->str + 24));
	63	samplesize = GUINT16_FROM_LE((uint16_t )(buf->str + 32));
	64	num_channels = GUINT16_FROM_LE((uint16_t )(buf->str + 22));
	65	/* TODO div0 */
	66	unitsize = samplesize / num_channels;
1d36b4d2	67
17bfaca6 BV	68	if (fmt_code == WAVE_FORMAT_PCM) {
	69	if (samplesize != 1 && samplesize != 2 && samplesize != 4) {
	70	sr_err("only 8, 16 or 32 bits per sample supported.");
	71	return SR_ERR;
	72	}
	73	} else if (fmt_code == WAVE_FORMAT_IEEE_FLOAT) {
	74	if (unitsize != 4) {
	75	sr_err("only 32-bit floats supported.");
	76	return SR_ERR;
	77	}
	78	} else {
	79	sr_err("Only PCM and floating point samples are supported.");
1d36b4d2	80	return SR_ERR;
17bfaca6	81	}
1d36b4d2	82
17bfaca6 BV	83	if (inc) {
	84	inc->fmt_code = fmt_code;
	85	inc->samplerate = samplerate;
	86	inc->samplesize = samplesize;
	87	inc->num_channels = num_channels;
	88	inc->unitsize = unitsize;
	89	inc->found_data = FALSE;
	90	}
1d36b4d2 BV	91
	92	return SR_OK;
	93	}
	94
17bfaca6	95	static int format_match(GHashTable *metadata)
1d36b4d2	96	{
17bfaca6	97	GString *buf;
1d36b4d2	98
17bfaca6 BV	99	buf = g_hash_table_lookup(metadata, GINT_TO_POINTER(SR_INPUT_META_HEADER));
17bfaca6 BV	100	if (strncmp(buf->str, "RIFF", 4))
1d36b4d2	101	return FALSE;
17bfaca6	102	if (strncmp(buf->str + 8, "WAVE", 4))
1d36b4d2	103	return FALSE;
17bfaca6	104	if (strncmp(buf->str + 12, "fmt ", 4))
1d36b4d2	105	return FALSE;
17bfaca6 BV	106	/*
	107	* Only gets called when we already know this is a WAV file, so
	108	* this parser can log error messages.
	109	*/
	110	if (parse_wav_header(buf, NULL) != SR_OK)
1d36b4d2 BV	111	return FALSE;
	112
	113	return TRUE;
	114	}
	115
17bfaca6	116	static int init(struct sr_input in, GHashTable options)
1d36b4d2	117	{
17bfaca6	118	(void)options;
1d36b4d2	119
1d36b4d2	120	in->sdi = sr_dev_inst_new(0, SR_ST_ACTIVE, NULL, NULL, NULL);
1d36b4d2 BV	121
	122	return SR_OK;
	123	}
	124
17bfaca6	125	static int find_data_chunk(GString *buf, int initial_offset)
cb41a838	126	{
17bfaca6	127	unsigned int offset, i;
cb41a838 BV	128
cb41a838 BV	129	offset = initial_offset;
17bfaca6 BV	130	while(offset < MIN(MAX_DATA_CHUNK_OFFSET, buf->len)) {
17bfaca6 BV	131	if (!memcmp(buf->str + offset, "data", 4))
cb41a838 BV	132	/* Skip into the samples. */
	133	return offset + 8;
	134	for (i = 0; i < 4; i++) {
17bfaca6 BV	135	if (!isalpha(buf->str[offset + i])
	136	&& !isascii(buf->str[offset + i])
	137	&& !isblank(buf->str[offset + i]))
cb41a838 BV	138	/* Doesn't look like a chunk ID. */
	139	return -1;
	140	}
	141	/* Skip past this chunk. */
17bfaca6	142	offset += 8 + GUINT32_FROM_LE((uint32_t )(buf->str + offset + 4));
cb41a838 BV	143	}
	144
	145	return offset;
	146	}
	147
17bfaca6	148	static int initial_receive(const struct sr_input *in)
1d36b4d2 BV	149	{
	150	struct sr_datafeed_packet packet;
	151	struct sr_datafeed_meta meta;
17bfaca6	152	struct sr_channel *ch;
1d36b4d2	153	struct sr_config *src;
17bfaca6 BV	154	struct context *inc;
	155	int i;
	156	char channelname[8];
	157
	158	if (!in->buf)
	159	/* Shouldn't happen. */
	160	return SR_ERR;
1d36b4d2	161
17bfaca6 BV	162	inc = in->sdi->priv = g_malloc(sizeof(struct context));
	163	if (parse_wav_header(in->buf, inc) != SR_OK)
	164	return SR_ERR;
	165
	166	for (i = 0; i < inc->num_channels; i++) {
	167	snprintf(channelname, 8, "CH%d", i + 1);
	168	ch = sr_channel_new(i, SR_CHANNEL_ANALOG, TRUE, channelname);
	169	in->sdi->channels = g_slist_append(in->sdi->channels, ch);
	170	}
1d36b4d2	171
29a27196	172	std_session_send_df_header(in->sdi, LOG_PREFIX);
1d36b4d2 BV	173
	174	packet.type = SR_DF_META;
	175	packet.payload = &meta;
17bfaca6	176	src = sr_config_new(SR_CONF_SAMPLERATE, g_variant_new_uint64(inc->samplerate));
1d36b4d2 BV	177	meta.config = g_slist_append(NULL, src);
1d36b4d2 BV	178	sr_session_send(in->sdi, &packet);
ec4063b8	179	sr_config_free(src);
1d36b4d2	180
17bfaca6 BV	181	return SR_OK;
	182	}
	183
	184	static void send_chunk(const struct sr_input *in, int offset, int num_samples)
	185	{
	186	struct sr_datafeed_packet packet;
	187	struct sr_datafeed_analog analog;
	188	struct context *inc;
	189	float fdata[CHUNK_SIZE];
	190	uint64_t sample;
	191	int total_samples, samplenum;
	192	char s, d;
1d36b4d2	193
17bfaca6 BV	194	inc = in->sdi->priv;
	195
	196	s = in->buf->str + offset;
	197	d = (char *)fdata;
cb41a838	198	memset(fdata, 0, CHUNK_SIZE);
17bfaca6 BV	199	total_samples = num_samples * inc->num_channels;
	200	for (samplenum = 0; samplenum < total_samples; samplenum++) {
	201	if (inc->fmt_code == WAVE_FORMAT_PCM) {
	202	sample = 0;
	203	memcpy(&sample, s, inc->unitsize);
	204	switch (inc->samplesize) {
	205	case 1:
	206	/* 8-bit PCM samples are unsigned. */
	207	fdata[samplenum] = (uint8_t)sample / 255.0;
	208	break;
	209	case 2:
	210	fdata[samplenum] = GINT16_FROM_LE(sample) / 32767.0;
	211	break;
	212	case 4:
	213	fdata[samplenum] = GINT32_FROM_LE(sample) / 65535.0;
	214	break;
	215	}
	216	} else {
	217	/* BINARY32 float */
cb41a838	218	#ifdef WORDS_BIGENDIAN
17bfaca6 BV	219	for (i = 0; i < inc->unitsize; i++)
17bfaca6 BV	220	d[i] = s[inc->unitsize - i];
cb41a838	221	#else
17bfaca6	222	memcpy(d, s, inc->unitsize);
cb41a838	223	#endif
1d36b4d2	224	}
17bfaca6 BV	225	s += inc->unitsize;
	226	d += inc->unitsize;
	227	}
	228	packet.type = SR_DF_ANALOG;
	229	packet.payload = &analog;
	230	analog.channels = in->sdi->channels;
	231	analog.num_samples = num_samples;
	232	analog.mq = 0;
	233	analog.mqflags = 0;
	234	analog.unit = 0;
	235	analog.data = fdata;
	236	sr_session_send(in->sdi, &packet);
	237	}
	238
	239	static int receive(const struct sr_input in, GString buf)
	240	{
	241	struct sr_datafeed_packet packet;
	242	struct context *inc;
	243	int offset, chunk_samples, total_samples, processed, max_chunk_samples, num_samples, i;
	244
	245	if (buf->len == 0) {
	246	/* End of stream. */
	247	packet.type = SR_DF_END;
1d36b4d2	248	sr_session_send(in->sdi, &packet);
17bfaca6	249	return SR_OK;
1d36b4d2 BV	250	}
1d36b4d2 BV	251
17bfaca6 BV	252	g_string_append_len(in->buf, buf->str, buf->len);
	253
	254	if (!in->sdi->priv) {
	255	if (initial_receive(in) != SR_OK)
	256	return SR_ERR;
	257	if (in->buf->len < MIN_DATA_CHUNK_OFFSET) {
	258	/*
	259	* Don't even get started until there's enough room
	260	* for the data segment to start.
	261	*/
	262	return SR_OK;
	263	}
	264	}
	265	inc = in->sdi->priv;
	266
	267	if (!inc->found_data) {
	268	/* Skip past size of 'fmt ' chunk. */
	269	i = 20 + GUINT32_FROM_LE((uint32_t )(in->buf->str + 16));
	270	offset = find_data_chunk(in->buf, i);
	271	if (offset < 0) {
	272	if (in->buf->len > MAX_DATA_CHUNK_OFFSET) {
	273	sr_err("Couldn't find data chunk.");
	274	return SR_ERR;
	275	}
	276	}
	277	inc->found_data = TRUE;
	278	} else
	279	offset = 0;
	280
	281	/* Round off up to the last channels * unitsize boundary. */
	282	chunk_samples = (in->buf->len - offset) / inc->num_channels / inc->unitsize;
	283	max_chunk_samples = CHUNK_SIZE / inc->num_channels / inc->unitsize;
	284	processed = 0;
	285	total_samples = chunk_samples;
	286	while (processed < total_samples) {
	287	if (chunk_samples > max_chunk_samples)
	288	num_samples = max_chunk_samples;
	289	else
	290	num_samples = chunk_samples;
	291	send_chunk(in, offset, num_samples);
	292	offset += num_samples * inc->unitsize;
	293	chunk_samples -= num_samples;
	294	processed += num_samples;
	295	}
	296
	297	if ((unsigned int)offset < in->buf->len) {
	298	/*
	299	* The incoming buffer wasn't processed completely. Stash
	300	* the leftover data for next time.
	301	*/
	302	g_string_erase(in->buf, 0, offset);
	303	} else
	304	g_string_truncate(in->buf, 0);
1d36b4d2 BV	305
	306	return SR_OK;
	307	}
	308
d4c93774	309	SR_PRIV struct sr_input_module input_wav = {
1d36b4d2	310	.id = "wav",
17bfaca6 BV	311	.name = "WAV",
	312	.desc = "WAV file",
	313	.metadata = { SR_INPUT_META_HEADER \| SR_INPUT_META_REQUIRED },
1d36b4d2 BV	314	.format_match = format_match,
1d36b4d2 BV	315	.init = init,
17bfaca6	316	.receive = receive,
1d36b4d2 BV	317	};
1d36b4d2 BV	318