[libsigrok.git] / src / session_driver.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 <config.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/time.h>
#include <zip.h>
#include <libsigrok/libsigrok.h>
#include "libsigrok-internal.h"

#define LOG_PREFIX "virtual-session"

/* size of payloads sent across the session bus */
/** @cond PRIVATE */
#define CHUNKSIZE (512 * 1024)
/** @endcond */

SR_PRIV struct sr_dev_driver session_driver_info;

struct session_vdev {
	char *sessionfile;
	char *capturefile;
	struct zip *archive;
	struct zip_file *capfile;
	int bytes_read;
	uint64_t samplerate;
	int unitsize;
	int num_channels;
	int num_analog_channels;
	int cur_analog_channel;
	GArray *analog_channels;
	int cur_chunk;
	gboolean finished;
};

static const uint32_t devopts[] = {
	SR_CONF_CAPTUREFILE | SR_CONF_SET,
	SR_CONF_CAPTURE_UNITSIZE | SR_CONF_GET | SR_CONF_SET,
	SR_CONF_NUM_LOGIC_CHANNELS | SR_CONF_SET,
	SR_CONF_NUM_ANALOG_CHANNELS | SR_CONF_SET,
	SR_CONF_SAMPLERATE | SR_CONF_GET | SR_CONF_SET,
	SR_CONF_SESSIONFILE | SR_CONF_SET,
};

static gboolean stream_session_data(struct sr_dev_inst *sdi)
{
	struct session_vdev *vdev;
	struct sr_datafeed_packet packet;
	struct sr_datafeed_logic logic;
	struct sr_datafeed_analog_old analog;
	struct zip_stat zs;
	int ret, got_data;
	char capturefile[16];
	void *buf;

	got_data = FALSE;
	vdev = sdi->priv;

	if (!vdev->capfile) {
		/* No capture file opened yet, or finished with the last
		 * chunked one. */
		if (vdev->capturefile && (vdev->cur_chunk == 0)) {
			/* capturefile is always the unchunked base name. */
			if (zip_stat(vdev->archive, vdev->capturefile, 0, &zs) != -1) {
				/* No chunks, just a single capture file. */
				vdev->cur_chunk = 0;
				if (!(vdev->capfile = zip_fopen(vdev->archive,
						vdev->capturefile, 0)))
					return FALSE;
				sr_dbg("Opened %s.", vdev->capturefile);
			} else {
				/* Try as first chunk filename. */
				snprintf(capturefile, 15, "%s-1", vdev->capturefile);
				if (zip_stat(vdev->archive, capturefile, 0, &zs) != -1) {
					vdev->cur_chunk = 1;
					if (!(vdev->capfile = zip_fopen(vdev->archive,
							capturefile, 0)))
						return FALSE;
					sr_dbg("Opened %s.", capturefile);
				} else {
					sr_err("No capture file '%s' in " "session file '%s'.",
							vdev->capturefile, vdev->sessionfile);
					return FALSE;
				}
			}
		} else {
			/* Capture data is chunked, advance to the next chunk. */
			vdev->cur_chunk++;
			snprintf(capturefile, 15, "%s-%d", vdev->capturefile,
					vdev->cur_chunk);
			if (zip_stat(vdev->archive, capturefile, 0, &zs) != -1) {
				if (!(vdev->capfile = zip_fopen(vdev->archive,
						capturefile, 0)))
					return FALSE;
				sr_dbg("Opened %s.", capturefile);
			} else if (vdev->cur_analog_channel < vdev->num_analog_channels) {
				vdev->capturefile = g_strdup_printf("analog-1-%d",
						vdev->num_channels + vdev->cur_analog_channel + 1);
				vdev->cur_analog_channel++;
				vdev->cur_chunk = 0;
				return TRUE;
			} else {
				/* We got all the chunks, finish up. */
				return FALSE;
			}
		}
	}

	buf = g_malloc(CHUNKSIZE);

	/* unitsize is not defined for purely analog session files. */
	if (vdev->unitsize)
		ret = zip_fread(vdev->capfile, buf,
				CHUNKSIZE / vdev->unitsize * vdev->unitsize);
	else
		ret = zip_fread(vdev->capfile, buf, CHUNKSIZE);

	if (ret > 0) {
		got_data = TRUE;
		if (vdev->cur_analog_channel != 0) {
			packet.type = SR_DF_ANALOG_OLD;
			packet.payload = &analog;
			analog.channels = g_slist_prepend(NULL,
					g_array_index(vdev->analog_channels,
						struct sr_channel *, vdev->cur_analog_channel - 1));
			analog.num_samples = ret / sizeof(float);
			analog.mq = SR_MQ_VOLTAGE;
			analog.unit = SR_UNIT_VOLT;
			analog.mqflags = SR_MQFLAG_DC;
			analog.data = (float *) buf;
		} else {
			if (ret % vdev->unitsize != 0)
				sr_warn("Read size %d not a multiple of the"
					" unit size %d.", ret, vdev->unitsize);
			packet.type = SR_DF_LOGIC;
			packet.payload = &logic;
			logic.length = ret;
			logic.unitsize = vdev->unitsize;
			logic.data = buf;
		}
		vdev->bytes_read += ret;
		sr_session_send(sdi, &packet);
	} else {
		/* done with this capture file */
		zip_fclose(vdev->capfile);
		vdev->capfile = NULL;
		if (vdev->cur_chunk != 0) {
			/* There might be more chunks, so don't fall through
			 * to the SR_DF_END here. */
			got_data = TRUE;
		}
	}
	g_free(buf);

	return got_data;
}

static int receive_data(int fd, int revents, void *cb_data)
{
	struct sr_dev_inst *sdi;
	struct session_vdev *vdev;

	(void)fd;
	(void)revents;

	sdi = cb_data;
	vdev = sdi->priv;

	if (!vdev->finished && !stream_session_data(sdi))
		vdev->finished = TRUE;
	if (!vdev->finished)
		return G_SOURCE_CONTINUE;

	if (vdev->capfile) {
		zip_fclose(vdev->capfile);
		vdev->capfile = NULL;
	}
	if (vdev->archive) {
		zip_discard(vdev->archive);
		vdev->archive = NULL;
	}

	std_session_send_df_end(sdi);

	return G_SOURCE_REMOVE;
}

/* driver callbacks */

static int dev_clear(const struct sr_dev_driver *di)
{
	struct drv_context *drvc;
	GSList *l;

	drvc = di->context;
	for (l = drvc->instances; l; l = l->next)
		sr_dev_inst_free(l->data);
	g_slist_free(drvc->instances);
	drvc->instances = NULL;

	return SR_OK;
}

static int dev_open(struct sr_dev_inst *sdi)
{
	struct sr_dev_driver *di;
	struct drv_context *drvc;
	struct session_vdev *vdev;

	di = sdi->driver;
	drvc = di->context;
	vdev = g_malloc0(sizeof(struct session_vdev));
	sdi->priv = vdev;
	drvc->instances = g_slist_append(drvc->instances, sdi);

	return SR_OK;
}

static int dev_close(struct sr_dev_inst *sdi)
{
	const struct session_vdev *const vdev = sdi->priv;
	g_free(vdev->sessionfile);
	g_free(vdev->capturefile);

	g_free(sdi->priv);
	sdi->priv = NULL;

	return SR_OK;
}

static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
		const struct sr_channel_group *cg)
{
	struct session_vdev *vdev;

	(void)cg;

	if (!sdi)
		return SR_ERR;

	vdev = sdi->priv;

	switch (key) {
	case SR_CONF_SAMPLERATE:
		*data = g_variant_new_uint64(vdev->samplerate);
		break;
	case SR_CONF_CAPTURE_UNITSIZE:
		*data = g_variant_new_uint64(vdev->unitsize);
		break;
	default:
		return SR_ERR_NA;
	}

	return SR_OK;
}

static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
		const struct sr_channel_group *cg)
{
	struct session_vdev *vdev;

	(void)cg;

	vdev = sdi->priv;

	switch (key) {
	case SR_CONF_SAMPLERATE:
		vdev->samplerate = g_variant_get_uint64(data);
		sr_info("Setting samplerate to %" PRIu64 ".", vdev->samplerate);
		break;
	case SR_CONF_SESSIONFILE:
		g_free(vdev->sessionfile);
		vdev->sessionfile = g_strdup(g_variant_get_string(data, NULL));
		sr_info("Setting sessionfile to '%s'.", vdev->sessionfile);
		break;
	case SR_CONF_CAPTUREFILE:
		g_free(vdev->capturefile);
		vdev->capturefile = g_strdup(g_variant_get_string(data, NULL));
		sr_info("Setting capturefile to '%s'.", vdev->capturefile);
		break;
	case SR_CONF_CAPTURE_UNITSIZE:
		vdev->unitsize = g_variant_get_uint64(data);
		break;
	case SR_CONF_NUM_LOGIC_CHANNELS:
		vdev->num_channels = g_variant_get_int32(data);
		break;
	case SR_CONF_NUM_ANALOG_CHANNELS:
		vdev->num_analog_channels = g_variant_get_int32(data);
		break;
	default:
		return SR_ERR_NA;
	}

	return SR_OK;
}

static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
		const struct sr_channel_group *cg)
{
	(void)sdi;
	(void)cg;

	switch (key) {
	case SR_CONF_DEVICE_OPTIONS:
		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
				devopts, ARRAY_SIZE(devopts), sizeof(uint32_t));
		break;
	default:
		return SR_ERR_NA;
	}

	return SR_OK;
}

static int dev_acquisition_start(const struct sr_dev_inst *sdi)
{
	struct session_vdev *vdev;
	int ret;
	GSList *l;
	struct sr_channel *ch;

	vdev = sdi->priv;
	vdev->bytes_read = 0;
	vdev->cur_analog_channel = 0;
	vdev->analog_channels = g_array_sized_new(FALSE, FALSE,
			sizeof(struct sr_channel *), vdev->num_analog_channels);
	for (l = sdi->channels; l; l = l->next) {
		ch = l->data;
		if (ch->type == SR_CHANNEL_ANALOG)
			g_array_append_val(vdev->analog_channels, ch);
	}
	vdev->cur_chunk = 0;
	vdev->finished = FALSE;

	sr_info("Opening archive %s file %s", vdev->sessionfile,
		vdev->capturefile);

	if (!(vdev->archive = zip_open(vdev->sessionfile, 0, &ret))) {
		sr_err("Failed to open session file '%s': "
		       "zip error %d.", vdev->sessionfile, ret);
		return SR_ERR;
	}

	std_session_send_df_header(sdi);

	/* freewheeling source */
	sr_session_source_add(sdi->session, -1, 0, 0, receive_data, (void *)sdi);

	return SR_OK;
}

static int dev_acquisition_stop(struct sr_dev_inst *sdi)
{
	struct session_vdev *vdev;

	vdev = sdi->priv;

	vdev->finished = TRUE;

	return SR_OK;
}

/** @private */
SR_PRIV struct sr_dev_driver session_driver = {
	.name = "virtual-session",
	.longname = "Session-emulating driver",
	.api_version = 1,
	.init = std_init,
	.cleanup = dev_clear,
	.scan = NULL,
	.dev_list = NULL,
	.dev_clear = dev_clear,
	.config_get = config_get,
	.config_set = config_set,
	.config_list = config_list,
	.dev_open = dev_open,
	.dev_close = dev_close,
	.dev_acquisition_start = dev_acquisition_start,
	.dev_acquisition_stop = dev_acquisition_stop,
	.context = NULL,
};
Commit	Line	Data
	1	/*
	2	* This file is part of the libsigrok project.
	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 <config.h>
	21	#include <sys/types.h>
	22	#include <sys/stat.h>
	23	#include <fcntl.h>
	24	#include <unistd.h>
	25	#include <sys/time.h>
	26	#include <zip.h>
	27	#include <libsigrok/libsigrok.h>
	28	#include "libsigrok-internal.h"
	29
	30	#define LOG_PREFIX "virtual-session"
	31
	32	/* size of payloads sent across the session bus */
	33	/** @cond PRIVATE */
	34	#define CHUNKSIZE (512 * 1024)
	35	/** @endcond */
	36
	37	SR_PRIV struct sr_dev_driver session_driver_info;
	38
	39	struct session_vdev {
	40	char *sessionfile;
	41	char *capturefile;
	42	struct zip *archive;
	43	struct zip_file *capfile;
	44	int bytes_read;
	45	uint64_t samplerate;
	46	int unitsize;
	47	int num_channels;
	48	int num_analog_channels;
	49	int cur_analog_channel;
	50	GArray *analog_channels;
	51	int cur_chunk;
	52	gboolean finished;
	53	};
	54
	55	static const uint32_t devopts[] = {
	56	SR_CONF_CAPTUREFILE \| SR_CONF_SET,
	57	SR_CONF_CAPTURE_UNITSIZE \| SR_CONF_GET \| SR_CONF_SET,
	58	SR_CONF_NUM_LOGIC_CHANNELS \| SR_CONF_SET,
	59	SR_CONF_NUM_ANALOG_CHANNELS \| SR_CONF_SET,
	60	SR_CONF_SAMPLERATE \| SR_CONF_GET \| SR_CONF_SET,
	61	SR_CONF_SESSIONFILE \| SR_CONF_SET,
	62	};
	63
	64	static gboolean stream_session_data(struct sr_dev_inst *sdi)
	65	{
	66	struct session_vdev *vdev;
	67	struct sr_datafeed_packet packet;
	68	struct sr_datafeed_logic logic;
	69	struct sr_datafeed_analog_old analog;
	70	struct zip_stat zs;
	71	int ret, got_data;
	72	char capturefile[16];
	73	void *buf;
	74
	75	got_data = FALSE;
	76	vdev = sdi->priv;
	77
	78	if (!vdev->capfile) {
	79	/* No capture file opened yet, or finished with the last
	80	* chunked one. */
	81	if (vdev->capturefile && (vdev->cur_chunk == 0)) {
	82	/* capturefile is always the unchunked base name. */
	83	if (zip_stat(vdev->archive, vdev->capturefile, 0, &zs) != -1) {
	84	/* No chunks, just a single capture file. */
	85	vdev->cur_chunk = 0;
	86	if (!(vdev->capfile = zip_fopen(vdev->archive,
	87	vdev->capturefile, 0)))
	88	return FALSE;
	89	sr_dbg("Opened %s.", vdev->capturefile);
	90	} else {
	91	/* Try as first chunk filename. */
	92	snprintf(capturefile, 15, "%s-1", vdev->capturefile);
	93	if (zip_stat(vdev->archive, capturefile, 0, &zs) != -1) {
	94	vdev->cur_chunk = 1;
	95	if (!(vdev->capfile = zip_fopen(vdev->archive,
	96	capturefile, 0)))
	97	return FALSE;
	98	sr_dbg("Opened %s.", capturefile);
	99	} else {
	100	sr_err("No capture file '%s' in " "session file '%s'.",
	101	vdev->capturefile, vdev->sessionfile);
	102	return FALSE;
	103	}
	104	}
	105	} else {
	106	/* Capture data is chunked, advance to the next chunk. */
	107	vdev->cur_chunk++;
	108	snprintf(capturefile, 15, "%s-%d", vdev->capturefile,
	109	vdev->cur_chunk);
	110	if (zip_stat(vdev->archive, capturefile, 0, &zs) != -1) {
	111	if (!(vdev->capfile = zip_fopen(vdev->archive,
	112	capturefile, 0)))
	113	return FALSE;
	114	sr_dbg("Opened %s.", capturefile);
	115	} else if (vdev->cur_analog_channel < vdev->num_analog_channels) {
	116	vdev->capturefile = g_strdup_printf("analog-1-%d",
	117	vdev->num_channels + vdev->cur_analog_channel + 1);
	118	vdev->cur_analog_channel++;
	119	vdev->cur_chunk = 0;
	120	return TRUE;
	121	} else {
	122	/* We got all the chunks, finish up. */
	123	return FALSE;
	124	}
	125	}
	126	}
	127
	128	buf = g_malloc(CHUNKSIZE);
	129
	130	/* unitsize is not defined for purely analog session files. */
	131	if (vdev->unitsize)
	132	ret = zip_fread(vdev->capfile, buf,
	133	CHUNKSIZE / vdev->unitsize * vdev->unitsize);
	134	else
	135	ret = zip_fread(vdev->capfile, buf, CHUNKSIZE);
	136
	137	if (ret > 0) {
	138	got_data = TRUE;
	139	if (vdev->cur_analog_channel != 0) {
	140	packet.type = SR_DF_ANALOG_OLD;
	141	packet.payload = &analog;
	142	analog.channels = g_slist_prepend(NULL,
	143	g_array_index(vdev->analog_channels,
	144	struct sr_channel *, vdev->cur_analog_channel - 1));
	145	analog.num_samples = ret / sizeof(float);
	146	analog.mq = SR_MQ_VOLTAGE;
	147	analog.unit = SR_UNIT_VOLT;
	148	analog.mqflags = SR_MQFLAG_DC;
	149	analog.data = (float *) buf;
	150	} else {
	151	if (ret % vdev->unitsize != 0)
	152	sr_warn("Read size %d not a multiple of the"
	153	" unit size %d.", ret, vdev->unitsize);
	154	packet.type = SR_DF_LOGIC;
	155	packet.payload = &logic;
	156	logic.length = ret;
	157	logic.unitsize = vdev->unitsize;
	158	logic.data = buf;
	159	}
	160	vdev->bytes_read += ret;
	161	sr_session_send(sdi, &packet);
	162	} else {
	163	/* done with this capture file */
	164	zip_fclose(vdev->capfile);
	165	vdev->capfile = NULL;
	166	if (vdev->cur_chunk != 0) {
	167	/* There might be more chunks, so don't fall through
	168	* to the SR_DF_END here. */
	169	got_data = TRUE;
	170	}
	171	}
	172	g_free(buf);
	173
	174	return got_data;
	175	}
	176
	177	static int receive_data(int fd, int revents, void *cb_data)
	178	{
	179	struct sr_dev_inst *sdi;
	180	struct session_vdev *vdev;
	181
	182	(void)fd;
	183	(void)revents;
	184
	185	sdi = cb_data;
	186	vdev = sdi->priv;
	187
	188	if (!vdev->finished && !stream_session_data(sdi))
	189	vdev->finished = TRUE;
	190	if (!vdev->finished)
	191	return G_SOURCE_CONTINUE;
	192
	193	if (vdev->capfile) {
	194	zip_fclose(vdev->capfile);
	195	vdev->capfile = NULL;
	196	}
	197	if (vdev->archive) {
	198	zip_discard(vdev->archive);
	199	vdev->archive = NULL;
	200	}
	201
	202	std_session_send_df_end(sdi);
	203
	204	return G_SOURCE_REMOVE;
	205	}
	206
	207	/* driver callbacks */
	208
	209	static int dev_clear(const struct sr_dev_driver *di)
	210	{
	211	struct drv_context *drvc;
	212	GSList *l;
	213
	214	drvc = di->context;
	215	for (l = drvc->instances; l; l = l->next)
	216	sr_dev_inst_free(l->data);
	217	g_slist_free(drvc->instances);
	218	drvc->instances = NULL;
	219
	220	return SR_OK;
	221	}
	222
	223	static int dev_open(struct sr_dev_inst *sdi)
	224	{
	225	struct sr_dev_driver *di;
	226	struct drv_context *drvc;
	227	struct session_vdev *vdev;
	228
	229	di = sdi->driver;
	230	drvc = di->context;
	231	vdev = g_malloc0(sizeof(struct session_vdev));
	232	sdi->priv = vdev;
	233	drvc->instances = g_slist_append(drvc->instances, sdi);
	234
	235	return SR_OK;
	236	}
	237
	238	static int dev_close(struct sr_dev_inst *sdi)
	239	{
	240	const struct session_vdev *const vdev = sdi->priv;
	241	g_free(vdev->sessionfile);
	242	g_free(vdev->capturefile);
	243
	244	g_free(sdi->priv);
	245	sdi->priv = NULL;
	246
	247	return SR_OK;
	248	}
	249
	250	static int config_get(uint32_t key, GVariant *data, const struct sr_dev_inst sdi,
	251	const struct sr_channel_group *cg)
	252	{
	253	struct session_vdev *vdev;
	254
	255	(void)cg;
	256
	257	if (!sdi)
	258	return SR_ERR;
	259
	260	vdev = sdi->priv;
	261
	262	switch (key) {
	263	case SR_CONF_SAMPLERATE:
	264	*data = g_variant_new_uint64(vdev->samplerate);
	265	break;
	266	case SR_CONF_CAPTURE_UNITSIZE:
	267	*data = g_variant_new_uint64(vdev->unitsize);
	268	break;
	269	default:
	270	return SR_ERR_NA;
	271	}
	272
	273	return SR_OK;
	274	}
	275
	276	static int config_set(uint32_t key, GVariant data, const struct sr_dev_inst sdi,
	277	const struct sr_channel_group *cg)
	278	{
	279	struct session_vdev *vdev;
	280
	281	(void)cg;
	282
	283	vdev = sdi->priv;
	284
	285	switch (key) {
	286	case SR_CONF_SAMPLERATE:
	287	vdev->samplerate = g_variant_get_uint64(data);
	288	sr_info("Setting samplerate to %" PRIu64 ".", vdev->samplerate);
	289	break;
	290	case SR_CONF_SESSIONFILE:
	291	g_free(vdev->sessionfile);
	292	vdev->sessionfile = g_strdup(g_variant_get_string(data, NULL));
	293	sr_info("Setting sessionfile to '%s'.", vdev->sessionfile);
	294	break;
	295	case SR_CONF_CAPTUREFILE:
	296	g_free(vdev->capturefile);
	297	vdev->capturefile = g_strdup(g_variant_get_string(data, NULL));
	298	sr_info("Setting capturefile to '%s'.", vdev->capturefile);
	299	break;
	300	case SR_CONF_CAPTURE_UNITSIZE:
	301	vdev->unitsize = g_variant_get_uint64(data);
	302	break;
	303	case SR_CONF_NUM_LOGIC_CHANNELS:
	304	vdev->num_channels = g_variant_get_int32(data);
	305	break;
	306	case SR_CONF_NUM_ANALOG_CHANNELS:
	307	vdev->num_analog_channels = g_variant_get_int32(data);
	308	break;
	309	default:
	310	return SR_ERR_NA;
	311	}
	312
	313	return SR_OK;
	314	}
	315
	316	static int config_list(uint32_t key, GVariant *data, const struct sr_dev_inst sdi,
	317	const struct sr_channel_group *cg)
	318	{
	319	(void)sdi;
	320	(void)cg;
	321
	322	switch (key) {
	323	case SR_CONF_DEVICE_OPTIONS:
	324	*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
	325	devopts, ARRAY_SIZE(devopts), sizeof(uint32_t));
	326	break;
	327	default:
	328	return SR_ERR_NA;
	329	}
	330
	331	return SR_OK;
	332	}
	333
	334	static int dev_acquisition_start(const struct sr_dev_inst *sdi)
	335	{
	336	struct session_vdev *vdev;
	337	int ret;
	338	GSList *l;
	339	struct sr_channel *ch;
	340
	341	vdev = sdi->priv;
	342	vdev->bytes_read = 0;
	343	vdev->cur_analog_channel = 0;
	344	vdev->analog_channels = g_array_sized_new(FALSE, FALSE,
	345	sizeof(struct sr_channel *), vdev->num_analog_channels);
	346	for (l = sdi->channels; l; l = l->next) {
	347	ch = l->data;
	348	if (ch->type == SR_CHANNEL_ANALOG)
	349	g_array_append_val(vdev->analog_channels, ch);
	350	}
	351	vdev->cur_chunk = 0;
	352	vdev->finished = FALSE;
	353
	354	sr_info("Opening archive %s file %s", vdev->sessionfile,
	355	vdev->capturefile);
	356
	357	if (!(vdev->archive = zip_open(vdev->sessionfile, 0, &ret))) {
	358	sr_err("Failed to open session file '%s': "
	359	"zip error %d.", vdev->sessionfile, ret);
	360	return SR_ERR;
	361	}
	362
	363	std_session_send_df_header(sdi);
	364
	365	/* freewheeling source */
	366	sr_session_source_add(sdi->session, -1, 0, 0, receive_data, (void *)sdi);
	367
	368	return SR_OK;
	369	}
	370
	371	static int dev_acquisition_stop(struct sr_dev_inst *sdi)
	372	{
	373	struct session_vdev *vdev;
	374
	375	vdev = sdi->priv;
	376
	377	vdev->finished = TRUE;
	378
	379	return SR_OK;
	380	}
	381
	382	/** @private */
	383	SR_PRIV struct sr_dev_driver session_driver = {
	384	.name = "virtual-session",
	385	.longname = "Session-emulating driver",
	386	.api_version = 1,
	387	.init = std_init,
	388	.cleanup = dev_clear,
	389	.scan = NULL,
	390	.dev_list = NULL,
	391	.dev_clear = dev_clear,
	392	.config_get = config_get,
	393	.config_set = config_set,
	394	.config_list = config_list,
	395	.dev_open = dev_open,
	396	.dev_close = dev_close,
	397	.dev_acquisition_start = dev_acquisition_start,
	398	.dev_acquisition_stop = dev_acquisition_stop,
	399	.context = NULL,
	400	};