kairos/daemon.c

/*
 * main.c: the daemon itself
 */

#include <unistd.h>
#include <syslog.h>
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <signal.h>

#include "config.h"
#include "trie.h"
#include "task.h"
#include "daemonize.h"

void term_handle(int sigval);
bool process(int fd);

static int sockfd;

int main (void) {
	openlog(cfg_log_ident, cfg_log_opt, cfg_log_facility); //I will probably close its fd a moment later, FIXME
	// No arguments, if you want something, go change source, according to documentation.
	daemonize(0);

	// Load saved state -- variable values and tasks
	trie_load(cfg_trie_file);
	task_load(cfg_task_file);

	// Set basic signal handlers
	sigset_t empty;
	sigemptyset(&empty); // Shall not fail
	struct sigaction *term_sigh = (struct sigaction *) malloc(sizeof(struct sigaction));
	term_sigh -> sa_handler = &term_handle;
	term_sigh -> sa_mask = empty;
	term_sigh -> sa_flags = 0;
	sigaction(SIGTERM, term_sigh, NULL);

	struct sigaction *chld_sigh = (struct sigaction *) malloc(sizeof(struct sigaction));
	chld_sigh -> sa_handler = SIG_IGN; // We don't care for children
	chld_sigh -> sa_mask = empty;
	chld_sigh -> sa_flags = SA_NOCLDWAIT;
	sigaction(SIGCHLD, chld_sigh, NULL);

	// Setup a socket to listen on
	sockfd = socket(AF_UNIX, SOCK_STREAM, 0);
	struct sockaddr_un addr;
	socklen_t addrsize = sizeof(struct sockaddr_un);
	addr.sun_family = AF_UNIX;
	memcpy(&addr.sun_path, cfg_socket, strlen(cfg_socket));
	bind(sockfd, (struct sockaddr *) &addr, sizeof(struct sockaddr_un));
	listen(sockfd, cfg_sock_maxclients);
	
	// Everything prepared
	syslog(cfg_log_facility | LOG_INFO, "Started");

	// Main loop: (everything else is handled by process() and signal handlers).
	while (true) {
		int fd = accept(sockfd, (struct sockaddr *) &addr, &addrsize);
		process(fd);
	}

	syslog(cfg_log_facility | LOG_CRIT, "Escaped infinite loop!");
	return 5;
}

void term_handle (int signum) {
	trie_save(cfg_trie_file);
	task_save(cfg_task_file);
	close(sockfd);
	unlink(cfg_socket);
	exit(0);
	return;
}

bool process(int fd) {}