libsigrok/hardware/common/scpi_usbtmc.c

169 lines
3.9 KiB
C

/*
* This file is part of the libsigrok project.
*
* Copyright (C) 2013 Martin Ling <martin-sigrok@earth.li>
*
* 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 "libsigrok.h"
#include "libsigrok-internal.h"
#include <glib.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
/* Message logging helpers with subsystem-specific prefix string. */
#define LOG_PREFIX "scpi_usbtmc: "
#define sr_log(l, s, args...) sr_log(l, LOG_PREFIX s, ## args)
#define sr_spew(s, args...) sr_spew(LOG_PREFIX s, ## args)
#define sr_dbg(s, args...) sr_dbg(LOG_PREFIX s, ## args)
#define sr_info(s, args...) sr_info(LOG_PREFIX s, ## args)
#define sr_warn(s, args...) sr_warn(LOG_PREFIX s, ## args)
SR_PRIV int scpi_usbtmc_open(void *priv)
{
struct sr_usbtmc_dev_inst *usbtmc = priv;
if ((usbtmc->fd = open(usbtmc->device, O_RDWR)) < 0)
return SR_ERR;
return SR_OK;
}
SR_PRIV int scpi_usbtmc_source_add(void *priv, int events, int timeout,
sr_receive_data_callback_t cb, void *cb_data)
{
struct sr_usbtmc_dev_inst *usbtmc = priv;
return sr_source_add(usbtmc->fd, events, timeout, cb, cb_data);
}
SR_PRIV int scpi_usbtmc_source_remove(void *priv)
{
struct sr_usbtmc_dev_inst *usbtmc = priv;
return sr_source_remove(usbtmc->fd);
}
SR_PRIV int scpi_usbtmc_send(void *priv, const char *command)
{
struct sr_usbtmc_dev_inst *usbtmc = priv;
int len, out;
len = strlen(command);
out = write(usbtmc->fd, command, len);
if (out < 0) {
sr_err("Write error: %s", strerror(errno));
return SR_ERR;
}
if (out < len) {
sr_dbg("Only sent %d/%d bytes of SCPI command: '%s'.", out,
len, command);
}
sr_spew("Successfully sent SCPI command: '%s'.", command);
return SR_OK;
}
SR_PRIV int scpi_usbtmc_receive(void *priv, char **scpi_response)
{
struct sr_usbtmc_dev_inst *usbtmc = priv;
GString *response;
char buf[256];
int len;
response = g_string_sized_new(1024);
len = read(usbtmc->fd, buf, sizeof(buf));
if (len < 0) {
sr_err("Read error: %s", strerror(errno));
g_string_free(response, TRUE);
return SR_ERR;
}
response = g_string_append_len(response, buf, len);
*scpi_response = response->str;
sr_dbg("SCPI response received (length %d): '%.50s'",
response->len, response->str);
g_string_free(response, FALSE);
return SR_OK;
}
SR_PRIV int scpi_usbtmc_read(void *priv, char *buf, int maxlen)
{
struct sr_usbtmc_dev_inst *usbtmc = priv;
int len;
len = read(usbtmc->fd, buf, maxlen);
if (len < 0) {
sr_err("Read error: %s", strerror(errno));
return SR_ERR;
}
return len;
}
SR_PRIV int scpi_usbtmc_close(void *priv)
{
struct sr_usbtmc_dev_inst *usbtmc = priv;
if (close(usbtmc->fd) < 0)
return SR_ERR;
return SR_OK;
}
static void scpi_usbtmc_free(void *priv)
{
return sr_usbtmc_dev_inst_free(priv);
}
SR_PRIV struct sr_scpi_dev_inst *scpi_usbtmc_dev_inst_new(const char *device)
{
struct sr_scpi_dev_inst *scpi;
struct sr_usbtmc_dev_inst *usbtmc;
scpi = g_try_malloc(sizeof(struct sr_scpi_dev_inst));
if (!(usbtmc = sr_usbtmc_dev_inst_new(device)))
{
g_free(scpi);
return NULL;
}
scpi->open = scpi_usbtmc_open;
scpi->source_add = scpi_usbtmc_source_add;
scpi->source_remove = scpi_usbtmc_source_remove;
scpi->send = scpi_usbtmc_send;
scpi->receive = scpi_usbtmc_receive;
scpi->read = scpi_usbtmc_read;
scpi->close = scpi_usbtmc_close;
scpi->free = scpi_usbtmc_free;
scpi->priv = usbtmc;
return scpi;
}