nuttx-apps/examples/zerocross/zerocross_main.c
Xiang Xiao 857158451b Unify the void cast usage
1.Remove void cast for function because many place ignore the returned value witout cast
2.Replace void cast for variable with UNUSED macro

Change-Id: Ie644129a563244a6397036789c4c3ea83c4e9b09
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
2020-01-02 23:21:01 +08:00

146 lines
4.6 KiB
C

/****************************************************************************
* examplex/zerocross/zerocross_main.c
*
* Copyright (C) 2015 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/ioctl.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/sensors/zerocross.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Configuration ************************************************************/
#ifndef CONFIG_SENSORS_ZEROCROSS
# error "CONFIG_SENSORS_ZEROCROSS is not defined in the configuration"
#endif
#ifndef CONFIG_EXAMPLES_ZEROCROSS_DEVNAME
# define CONFIG_EXAMPLES_ZEROCROSS_DEVNAME "/dev/zc0"
#endif
#ifndef CONFIG_EXAMPLES_ZEROCROSS_SIGNO
# define CONFIG_EXAMPLES_ZEROCROSS_SIGNO 13
#endif
/* Helpers ******************************************************************/
#ifndef MIN
# define MIN(a,b) (a < b ? a : b)
#endif
#ifndef MAX
# define MAX(a,b) (a > b ? a : b)
#endif
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* zerocross_main
****************************************************************************/
int main(int argc, FAR char *argv[])
{
struct sigevent event;
int fd;
int tmp;
int ret;
int errcode = EXIT_FAILURE;
/* Open the zerocross device */
fd = open(CONFIG_EXAMPLES_ZEROCROSS_DEVNAME, O_RDONLY);
if (fd < 0)
{
fprintf(stderr, "ERROR: Failed to open %s: %d\n",
CONFIG_EXAMPLES_ZEROCROSS_DEVNAME, errno);
return EXIT_FAILURE;
}
/* Register to receive a signal on every zero cross event */
event.sigev_notify = SIGEV_SIGNAL;
event.sigev_signo = CONFIG_EXAMPLES_ZEROCROSS_SIGNO;
ret = ioctl(fd, ZCIOC_REGISTER, (unsigned long)((uintptr_t)&event));
if (ret < 0)
{
fprintf(stderr, "ERROR: ioctl(ZCIOC_REGISTER) failed: %d\n", errno);
goto errout_with_fd;
}
/* Then loop, receiving signals indicating zero cross events. */
for (; ; )
{
struct siginfo value;
sigset_t set;
ssize_t nread;
/* Wait for a signal */
sigemptyset(&set);
sigaddset(&set, CONFIG_EXAMPLES_ZEROCROSS_SIGNO);
ret = sigwaitinfo(&set, &value);
if (ret < 0)
{
fprintf(stderr, "ERROR: sigwaitinfo() failed: %d\n", errno);
goto errout_with_fd;
}
/* Show the value accompanying the signal */
printf("Signal received!\n");
printf("Sample = %d\n", value.si_value.sival_int);
}
errcode = EXIT_SUCCESS;
errout_with_fd:
close(fd);
return errcode;
}