libsigrok/std.c

291 lines
7.7 KiB
C

/*
* This file is part of the libsigrok project.
*
* Copyright (C) 2013 Uwe Hermann <uwe@hermann-uwe.de>
*
* 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 2 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, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
/** @file
* Standard API helper functions.
* @internal
*/
#include <glib.h>
#include "libsigrok.h"
#include "libsigrok-internal.h"
#define LOG_PREFIX "std"
/**
* Standard sr_driver_init() API helper.
*
* This function can be used to simplify most driver's init() API callback.
*
* It creates a new 'struct drv_context' (drvc), assigns sr_ctx to it, and
* then 'drvc' is assigned to the 'struct sr_dev_driver' (di) that is passed.
*
* @param sr_ctx The libsigrok context to assign.
* @param di The driver instance to use.
* @param[in] prefix A driver-specific prefix string used for log messages.
*
* @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
* SR_ERR_MALLOC upon memory allocation errors.
*/
SR_PRIV int std_init(struct sr_context *sr_ctx, struct sr_dev_driver *di,
const char *prefix)
{
struct drv_context *drvc;
if (!di) {
sr_err("%sInvalid driver, cannot initialize.", prefix);
return SR_ERR_ARG;
}
if (!(drvc = g_try_malloc(sizeof(struct drv_context)))) {
sr_err("%sDriver context malloc failed.", prefix);
return SR_ERR_MALLOC;
}
drvc->sr_ctx = sr_ctx;
drvc->instances = NULL;
di->priv = drvc;
return SR_OK;
}
/**
* Standard API helper for sending an SR_DF_HEADER packet.
*
* This function can be used to simplify most driver's
* dev_acquisition_start() API callback.
*
* @param sdi The device instance to use.
* @param prefix A driver-specific prefix string used for log messages.
* Must not be NULL. An empty string is allowed.
*
* @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or
* SR_ERR upon other errors.
*/
SR_PRIV int std_session_send_df_header(const struct sr_dev_inst *sdi,
const char *prefix)
{
int ret;
struct sr_datafeed_packet packet;
struct sr_datafeed_header header;
if (!prefix) {
sr_err("Invalid prefix.");
return SR_ERR_ARG;
}
sr_dbg("%sStarting acquisition.", prefix);
/* Send header packet to the session bus. */
sr_dbg("%sSending SR_DF_HEADER packet.", prefix);
packet.type = SR_DF_HEADER;
packet.payload = (uint8_t *)&header;
header.feed_version = 1;
gettimeofday(&header.starttime, NULL);
if ((ret = sr_session_send(sdi, &packet)) < 0) {
sr_err("%sFailed to send header packet: %d.", prefix, ret);
return ret;
}
return SR_OK;
}
#ifdef HAVE_LIBSERIALPORT
/*
* Standard serial driver dev_open() helper.
*
* This function can be used to implement the dev_open() driver API
* callback in drivers that use a serial port. The port is opened
* with the SERIAL_RDWR and SERIAL_NONBLOCK flags.
*
* If the open succeeded, the status field of the given sdi is set
* to SR_ST_ACTIVE.
*
* @retval SR_OK Success.
* @retval SR_ERR Serial port open failed.
*/
SR_PRIV int std_serial_dev_open(struct sr_dev_inst *sdi)
{
struct sr_serial_dev_inst *serial;
serial = sdi->conn;
if (serial_open(serial, SERIAL_RDWR | SERIAL_NONBLOCK) != SR_OK)
return SR_ERR;
sdi->status = SR_ST_ACTIVE;
return SR_OK;
}
/*
* Standard serial driver dev_close() helper.
*
* This function can be used to implement the dev_close() driver API
* callback in drivers that use a serial port.
*
* After closing the port, the status field of the given sdi is set
* to SR_ST_INACTIVE.
*
* @retval SR_OK Success.
*/
SR_PRIV int std_serial_dev_close(struct sr_dev_inst *sdi)
{
struct sr_serial_dev_inst *serial;
serial = sdi->conn;
if (serial && sdi->status == SR_ST_ACTIVE) {
serial_close(serial);
sdi->status = SR_ST_INACTIVE;
}
return SR_OK;
}
/*
* Standard sr_session_stop() API helper.
*
* This function can be used to simplify most (serial port based) driver's
* dev_acquisition_stop() API callback.
*
* @param sdi The device instance for which acquisition should stop.
* Must not be NULL.
* @param cb_data Opaque 'cb_data' pointer. Must not be NULL.
* @param dev_close_fn Function pointer to the driver's dev_close().
* Must not be NULL.
* @param serial The serial device instance (struct serial_dev_inst *).
* Must not be NULL.
* @param prefix A driver-specific prefix string used for log messages.
* Must not be NULL. An empty string is allowed.
*
* @retval SR_OK Success.
* @retval SR_ERR_ARG Invalid arguments.
* @retval SR_ERR_DEV_CLOSED Device is closed.
* @retval SR_ERR Other errors.
*/
SR_PRIV int std_serial_dev_acquisition_stop(struct sr_dev_inst *sdi,
void *cb_data, dev_close_t dev_close_fn,
struct sr_serial_dev_inst *serial, const char *prefix)
{
int ret;
struct sr_datafeed_packet packet;
if (!prefix) {
sr_err("Invalid prefix.");
return SR_ERR_ARG;
}
if (sdi->status != SR_ST_ACTIVE) {
sr_err("%sDevice inactive, can't stop acquisition.", prefix);
return SR_ERR_DEV_CLOSED;
}
sr_dbg("%sStopping acquisition.", prefix);
if ((ret = serial_source_remove(serial)) < 0) {
sr_err("%sFailed to remove source: %d.", prefix, ret);
return ret;
}
if ((ret = dev_close_fn(sdi)) < 0) {
sr_err("%sFailed to close device: %d.", prefix, ret);
return ret;
}
/* Send SR_DF_END packet to the session bus. */
sr_dbg("%sSending SR_DF_END packet.", prefix);
packet.type = SR_DF_END;
packet.payload = NULL;
if ((ret = sr_session_send(cb_data, &packet)) < 0) {
sr_err("%sFailed to send SR_DF_END packet: %d.", prefix, ret);
return ret;
}
return SR_OK;
}
#endif
/*
* Standard driver dev_clear() helper.
*
* This function can be used to implement the dev_clear() driver API
* callback. dev_close() is called before every sr_dev_inst is cleared.
*
* The only limitation is driver-specific device contexts (sdi->priv).
* These are freed, but any dynamic allocation within structs stored
* there cannot be freed.
*
* @param driver The driver which will have its instances released.
* @param clear_private If not NULL, this points to a function called
* with sdi->priv as argument. The function can then clear any device
* instance-specific resources kept there. It must also clear the struct
* pointed to by sdi->priv.
*
* @return SR_OK on success.
*/
SR_PRIV int std_dev_clear(const struct sr_dev_driver *driver,
std_dev_clear_t clear_private)
{
struct drv_context *drvc;
struct sr_dev_inst *sdi;
GSList *l;
int ret;
if (!(drvc = driver->priv))
/* Driver was never initialized, nothing to do. */
return SR_OK;
ret = SR_OK;
for (l = drvc->instances; l; l = l->next) {
if (!(sdi = l->data)) {
ret = SR_ERR_BUG;
continue;
}
if (driver->dev_close)
driver->dev_close(sdi);
if (sdi->conn) {
#ifdef HAVE_LIBSERIALPORT
if (sdi->inst_type == SR_INST_SERIAL)
sr_serial_dev_inst_free(sdi->conn);
#endif
#ifdef HAVE_LIBUSB_1_0
if (sdi->inst_type == SR_INST_USB)
sr_usb_dev_inst_free(sdi->conn);
#endif
if (sdi->inst_type == SR_INST_SCPI)
sr_scpi_free(sdi->conn);
}
if (clear_private)
clear_private(sdi->priv);
else
g_free(sdi->priv);
sr_dev_inst_free(sdi);
}
g_slist_free(drvc->instances);
drvc->instances = NULL;
return ret;
}