src/light_thread.c


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// XXX sigwait instead of signal handler...

#include <stdio.h>

#include "common.h"
#include "consts.h"
#include "config.h"
#include "backlight.h"

static pid_t keypress_pid;

uint64_t time_since_press(void) {
	struct timeval now;

	uint64_t now_usec;
	uint64_t press_usec;
	uint64_t diff;

	gettimeofday(&now, NULL);

	now_usec  = now.tv_sec * 1000000L;
	now_usec += now.tv_usec;

	press_usec  = last_press->tv_sec * 1000000L;
	press_usec += last_press->tv_usec;

	diff = now_usec - press_usec;

	return diff;
}

void handler(int _) {
	if (time_since_press() > BACKLIGHT_TIME) {
		backlight_off();
	} else {
		backlight_on();
		usleep(BACKLIGHT_TIME);

		raise(SIGCONT);
	}
}

void light_thread() {
	signal(SIGCONT, handler);

	for (;;) pause();
	__builtin_unreachable();
}