Dutor

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <fcntl.h> //~ O_RDWR, S_IRWXU etc.
#include <pthread.h>
#include <time.h>
#include <limits.h>
#include <signal.h>
 
void daemonize();
 
//~ thread functions
void *listen_ms(void *);
void *listen_kb(void *);
 
//~ time stamp, keeping the time
//~ when the last KB or Mouse event happened.
volatile time_t stamp;
 
//~ mutex keeping stamp consistent.
pthread_mutex_t stamp_mutex;
 
int
main()
{
    daemonize();
    //~ initialize the mutex, stamp
    pthread_mutex_init(&stamp_mutex, NULL);
    //time(&stamp);
    stamp = time(NULL);
 
    //~ create two threads monitoring the Mouse and Keyboard.
    pthread_t ms_tid, kb_tid;
    if(pthread_create(&ms_tid, NULL, listen_ms, NULL) != 0)
    {
        perror("pthread_create");
        exit(1);
    }
    if(pthread_create(&kb_tid, NULL, listen_kb, NULL) != 0)
    {
        perror("pthread_create");
        exit(1);
    }
 
    unsigned int interval = 60 * 30;
    while(1)
    {
        sleep(1);
        pthread_mutex_lock(&stamp_mutex);
        if( time(NULL) - stamp > interval )
        {
            /*printf("shutdown\n");*/
            /*fflush(stdin);*/
            system("init 0");
        }
        pthread_mutex_unlock(&stamp_mutex);
    }
    //~ join the threads, though it'll never be excuted.
    pthread_join(ms_tid, NULL);
    pthread_join(kb_tid, NULL);
 
    return 0;
}
 
void *
listen_ms(void * arg)
{
    int fd = open("/dev/input/mice", O_RDONLY);
    if(fd < 0)
    {
        perror("open mice");
        exit(1);
    }
    char buf[256];
    while( read(fd, buf, sizeof(buf)) > 0 )
    {
        /*printf("Moused Moved.\n");*/
        pthread_mutex_lock(&stamp_mutex);
        //time(&stamp);
        stamp = time(NULL);
        pthread_mutex_unlock(&stamp_mutex);
    }
    close(fd);
}
 
void *
listen_kb(void * arg)
{
    int fd = open("/dev/input/event3", O_RDONLY);
    if(fd < 0)
    {
        perror("open event3");
        exit(1);
    }
    char buf[256];
    while( read(fd, buf, sizeof(buf)) > 0 )
    {
        /*printf("Key Hit.\n");*/
        pthread_mutex_lock(&stamp_mutex);
        //time(&stamp);
        stamp = time(NULL);
        pthread_mutex_unlock(&stamp_mutex);
    }
    close(fd);
}
 
void
daemonize()
{
    if( fork() > 0)
        exit(0);
    setsid();
    close(0);
    close(1);
    close(2);
    int fd = open("/dev/null", O_RDWR);
    //int fd = open("log.txt", O_RDWR);
    dup2(fd, 1);
    dup2(fd, 2);
    chdir("/");
    umask(0);
    signal(SIGCHLD, SIG_IGN);
}