#include <sys/types.h>
#include <string.h>
#include <sys/mman.h>
#include <sys/wait.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>
#include <fcntl.h>
#include <stdbool.h>

int
main(int argc, char *argv[])
{
    int pip1[2];
    pipe2(pip1, O_CLOEXEC);

    if (!fork()) {
        dup2(pip1[1], 1);
        execlp(argv[1], argv[1], NULL);
    }

    int pip2[2];
    pipe2(pip2, O_CLOEXEC);
    if (!fork()) {
        dup2(pip1[0], 0);
        dup2(pip2[1], 1);

        close(pip1[0]);
        close(pip1[1]);
        close(pip2[0]);
        close(pip2[1]);

        int cmd2_pid = fork();

        if (cmd2_pid == 0) {
            int file = open(argv[5], O_WRONLY | O_CREAT | O_TRUNC | O_CLOEXEC, 0600);
            dup2(file, 2);
            execlp(argv[2], argv[2], NULL);
        }

        int st;
        waitpid(cmd2_pid, &st, 0);

        if (!WIFEXITED(st) || WEXITSTATUS(st) != 0) {
            _exit(0);
        }

        if (!fork()) {
            execlp(argv[3], argv[3], NULL);
        }

        wait(NULL);
        _exit(0);
    }

    if (!fork()) {
        dup2(pip2[0], 0);
        execlp(argv[4], argv[4], NULL);
    }

    wait(NULL);
    wait(NULL);
    wait(NULL);

    return 0;
}