pipowerd.c File Reference

Monitor GPIO for the SHUTDOWN signal. More...

#include <errno.h>
#include <fcntl.h>
#include <getopt.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <time.h>
#include <unistd.h>
#include <linux/gpio.h>

Data Structures
struct	config
	Holds our global configuration. More...

Macros
#define	_POSIX_C_SOURCE   200809L
#define	DEFAULT_GPIO_DEV   "/dev/gpiochip0"
	On which gpio device is our pin of interest?
#define	DEFAULT_PIN   17
	GPIO pin to monitor for the shutdown signal.
#define	DEFAULT_SHUTDOWN_COMMAND   "/bin/systemctl poweroff"
	Command to run when a shutdown signal is received.
#define	OPT_GPIO_DEV   'd'
	--device|-d <device>
#define	OPT_PIN   'p'
	--pin|-p <pin>
#define	OPT_SHUTDOWN_COMMAND   'c'
	--shutdown-command|-c <command>
#define	OPT_VERBOSE   'v'
	--verbose|-v (may be specified multiple times)
#define	OPT_IGNORE_INITIAL_STATE   'i'
	--ignore-initial-state|-i
#define	OPT_HELP   'h'
	--help|-h
#define	OPTSTRING   "d:p:c:vih"
	Valid single character options.

Functions
void	init_config ()
	Initialize global configuration with default values.
void	usage (FILE *out)
	Display a usage message.
void	monitor_shutdown_pin ()
	Loop until we detect a shutdown request. More...
void	parse_args (int argc, char *argv[])
	Handle command line options.
int	main (int argc, char *argv[])

Variables
const struct option	longopts []
	Configure options handling. More...
struct config	config

Detailed Description

Monitor GPIO for the SHUTDOWN signal.

Function Documentation

void monitor_shutdown_pin

(

)

Loop until we detect a shutdown request.

First check the initial state of the shutdown pin. If a shutdown request has been asserted, exit immediately unless --ignore-initial-state was provided. If there is no active shutdown request, monitor the pin for rising edge events and exit when one is received.

Variable Documentation

const struct option longopts[]

Initial value:

= {
    {"gpio-device", required_argument, 0, OPT_GPIO_DEV},
    {"gpio-pin", required_argument, 0, OPT_PIN},
    {"shutdown-command", required_argument, 0, OPT_SHUTDOWN_COMMAND},
    {"ignore-initial-state", required_argument, 0, OPT_IGNORE_INITIAL_STATE},
    {"verbose", no_argument, 0, OPT_VERBOSE},
    {"help", no_argument, 0, OPT_HELP},
}

Configure options handling.