#include <unistd.h>

#include <fcntl.h>

#include <time.h>

#include "apue.h"

static void sig_alrm(int signo)

{

    /* nothing to do, just returning wakes up sigsuspend */

}

static void sig_usr1(int signo)

{

}

//static void sig_alrm_test(int signo)

//{

//    err_msg("left an alrm");

//}

unsigned int sleep(unsigned int seconds)

{

    struct sigaction newact, oldact;

    sigset_t newmask, oldmask, suspmask;

    unsigned int unslept;

    timespec ts;            // ++

    ts.tv_sec = ;         // ++

    ts.tv_nsec = ;         // ++

    /* set our handler, save previous information */

    newact.sa_handler = sig_alrm;

    sigemptyset(&newact.sa_mask);

    newact.sa_flags = ;

    sigaction(SIGALRM, &newact, &oldact);

    /* block SIGALRM and save current signal mask */

    sigemptyset(&newmask);

    sigaddset(&newmask, SIGALRM);

    sigprocmask(SIG_BLOCK, &newmask, &oldmask);

    alarm(seconds);

    suspmask = oldmask;

    /* make sure SIGALRM isn't block */

    sigdelset(&suspmask, SIGALRM);

    /* wait for any signal to be caught */

    sigsuspend(&suspmask);

    nanosleep(&ts, NULL);                   // ++

    /* some signal has been caught, SIGALRM is now blocked */

    unslept = alarm();

    /* reset previous action */

    sigaction(SIGALRM, &oldact, NULL);

    /* reset signal mask, which unblocks SIGALRM */

    sigprocmask(SIG_SETMASK, &oldmask, NULL);

    return unslept;

}

int main(int argc, char *argv[])

{

    struct sigaction useract;

    struct sigaction alrmact;

    useract.sa_handler = sig_usr1;

    sigemptyset(&useract.sa_mask);

    useract.sa_flags = ;

    if (sigaction(SIGUSR1, &useract, NULL) < )

        err_sys("SIG SUR1 error");

//    alrmact.sa_handler = sig_alrm_test;

//    sigemptyset(&alrmact.sa_mask);

//    alrmact.sa_flags = 0;

//    if (sigaction(SIGALRM, &alrmact, NULL) < 0)

//        err_sys("SIG ALRM error");

    sleep();

    return ;

}