02_exercise/signal_handler.c


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#include "signal_handler.h"

#include <wait.h>
#include <stdio.h>
#include <unistd.h>

void signal_handler(int signal) {
    if (signal == SIGINT) {
        interrupt_issued = 1;
    } else if (signal == SIGTSTP) {
        stop_issued = 1;
        kill(getpid(), SIGINT);
    }
}

void handle_interrupt(pid_t pid) {
    int status;
    if (stop_issued) {
        stop_issued = 0;
        interrupt_issued = 0;
    } else if (interrupt_issued) {
        interrupt_issued = 0;
        kill(pid, SIGKILL);
        waitpid(pid, &status, 0);
        printf("Killed [%ld]\n", (long)pid);
        return;
    }
    kill(pid, SIGCONT);
    printf("[%ld]\n", (long)pid);
}