/* test for using select system call, signal handling and timeouts */

#include <unistd.h>
#include <sys/types.h>
#include <sys/time.h>
#include <stdio.h>
#include <signal.h>
#include <errno.h>
#include <fcntl.h>

#include "closure.h"

void set_signal_handlers(void);
void play_with_select(void);

fd_set fd_read;
fd_set fd_write;
fd_set fd_error;

int n_fd;
int n_fd_capacity;

closure *read_h_by_fd;
closure *write_h_by_fd;

void set_read_h(int fd) {
	if (fd > n_fd_capacity) {
		read
	}
	if (fd > n_fd) {
		
	}
}

int main(int argc, char *argv[]) {
	set_signal_handlers();
	play_with_select();
	return 0;
}

void sigint_h(int i) {
	printf("handled SIGINT: %d\n", i);
}

void set_signal_handlers(void) {
	struct sigaction sa;

	sa.sa_handler = &sigint_h;
	sigemptyset(&sa.sa_mask); // check for -1 rv?
	sa.sa_flags = 0; //SA_RESTART;

	sigaction(SIGINT, &sa, NULL); // check for -1 rv?
}

void play_with_select(void) {
	fd_set o_fd_read, o_fd_write, o_fd_error;
	int n;
	struct timeval select_timeout;

	FD_ZERO(&fd_read);
	FD_ZERO(&fd_write);
	FD_ZERO(&fd_error);

	fcntl(STDIN_FILENO, F_SETFL, O_NONBLOCK);
	fcntl(STDOUT_FILENO, F_SETFL, O_NONBLOCK);

	FD_SET(STDIN_FILENO, &fd_read);
//	FD_SET(STDOUT_FILENO, &fd_write);

	n_fd = 2;

	o_fd_read = fd_read;
	o_fd_write = fd_write;
	o_fd_error = fd_error;

	select_timeout.tv_sec = 5;
	select_timeout.tv_usec = 0;

	// select - this is Linux specific select usage, relying on the timeout being set to the remaining time
	do {
		n = select(fd_limit, &o_fd_read, &o_fd_write, &o_fd_error, &select_timeout);
	} while (n == -1 && errno == EINTR);
	if (n == -1) {
		if (errno == EINTR) 
		perror("select failed");
		printf("time remaining: %d %d\n", select_timeout.tv_sec, select_timeout.tv_usec);
		exit(1);
	}
}