#include <sys/types.h>
#include <sys/ptrace.h>
#include <sys/socket.h>
#include <sys/wait.h>

#include <netinet/in.h>

#include <poll.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>


int main()
{
	pid_t p;

	p = fork();
	if (p < 0) {
		perror("fork");
		exit(1);
	}

	if (p > 0) {
		int rc;
		int status;

		sleep(1);	/* let the child do its setup */

		rc = ptrace(PT_ATTACH, p, 0, 0);
		if (rc < 0) {
			perror("ptrace(PT_ATTACH)");
			goto kill_exit;
		}
#if 1
		/* Wait for the child process to stop. */
		if (waitpid(p, &status, WUNTRACED) == -1) {
			perror("waitpid(WUNTRACED)");
			goto kill_exit;
		}

		/* Check for an unexpected status. */
		if (WIFSTOPPED(status) == 0)
			fprintf(stderr, "child process status: 0x%x", status);
#else
		sleep(20);	/* XXX XXX XXX */
#endif
		rc = ptrace(PT_CONTINUE, p, (caddr_t)1, 0);
		if (rc < 0) {
			perror("ptrace(PT_CONTINUE)");
			goto kill_exit;
		}

		sleep(1);	/* let things settle down */

		if (ptrace(PT_DETACH, p, 0, 0) == 0) {
			printf("the child is alive\n");
			goto kill_exit;
		} else
			perror("ptrace(PT_DETACH)");

		printf("the child is dead\n");
		exit(0);

	kill_exit:
		kill(p, SIGKILL);
		exit(1);
	} else {
		struct pollfd pfd;
		struct sockaddr_in sa;
		int s;

		s = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
		if (s < 0) {
			perror("socket");
			exit(1);
		}

		memset(&sa, 0, sizeof(sa));
		sa.sin_family = AF_INET;
		sa.sin_port = htons(4444); /* XXX */
		sa.sin_addr.s_addr = INADDR_ANY;

		if (bind(s, (struct sockaddr *)&sa, sizeof(sa)) < 0) {
			perror("bind");
			exit(1);
		}

		if (listen(s, 1) < 0) {
			perror("listen");
			exit(1);
		}

		pfd.fd = s;
		pfd.revents = 0;
		pfd.events = POLLIN;

		if (poll(&pfd, 1, INFTIM) < 0) {
			perror("poll");
			exit(1);
		}

		printf("successfully accepted\n");
		exit(0);
	}
}