#ifdef Posix_compile
#include <unistd.h>
#include <errno.h>
#include <signal.h>
#include <pthread.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/mman.h>
#include <sys/sem.h>
#include <semaphore.h>
#include <fcntl.h>
#else
#include <windows.h>
#endif

#include <stdio.h>
#include <stdlib.h>
#include <string.h>


#define SIZE 4096

void error_handler(char *message) {
	fprintf(stderr, "%s\n", message);
	perror("ERROR");
	exit(EXIT_FAILURE);
}

int N;
pid_t child[64];
int indx = 0;
char *buffer[1024];


void SIGINT_handler_main(int a, siginfo_t *b, void *c) {
	int i;
	for(i = 0; i < N; i++) {
		kill(child[i], SIGINT);
	}
}



void SIGINT_handler_child(int a, siginfo_t *b, void *c) {
	int i;
	printf("Strings of process %d:\n",getpid());
	for (i = 0; i < indx; i++) {
		printf("%s	",buffer[i]);
	}
	printf("\n");
}



int main(int argc, char** argv){

	N = argc-1;
	pid_t pid;
	void *shm;
	int sem, i, ret;
	sigset_t set;
	struct sembuf oper;
	struct sigaction act;

	if (argc < 2) {
		error_handler("Not valid input");
	}
	shm = mmap(NULL, SIZE, PROT_READ|PROT_WRITE, MAP_SHARED|MAP_ANONYMOUS, 0, 0);
	if (shm == NULL) {
		error_handler("mmap has failed");
	}
	sem = semget(IPC_PRIVATE, N + 1, IPC_CREAT|0666);
	if (sem == -1) {
		error_handler("semget has failed");
	}
	for (i = 0; i < N; i++) {
		ret = semctl(sem, i, SETVAL, 0);
		if (ret == -1) {
			error_handler("semctl has failed");
		}
	}
	ret = semctl(sem, N, SETVAL, N);
	if (ret == -1) {
		error_handler("semctl has failed");
	}
	for (i = 0; i < N; i++) {
		pid = fork();
		if (pid == -1) {
			error_handler("fork has failed");
		}
		if (pid == 0) {
			char my_str[1024];
			int my_index = i;

			if (strcpy(my_str, argv[my_index + 1]) == NULL) {
				error_handler("strcpy has failed");
			}
			ret = sigfillset(&set);
			if (ret == -1) {
				error_handler("sigfillset has failed");
			}
			act.sa_sigaction = SIGINT_handler_child;
			act.sa_mask = set;
			act.sa_flags = 0;

			ret = sigaction(SIGINT, &act, NULL);
			if (ret == -1) {
				error_handler("sigaction has failed");
			}
			while (1) {
				oper.sem_num = my_index;
				oper.sem_op = -1;
				oper.sem_flg = 0;

			step1:	ret = semop(sem, &oper, 1);
				if (ret == -1) {
					if (errno == EINTR) goto step1;
					error_handler("semop has failed");
				}
				if (strstr(my_str,(char*)shm) != NULL) {
			step2:		buffer[indx] = malloc(strlen((char*)shm)+1);
					if (buffer[indx] == NULL) {
						if (errno == EINTR) goto step2;
						error_handler("malloc has failed");
					}
					if (strcpy(buffer[indx], (char *)shm) == NULL) {
						error_handler("strcpy has failed");
					}
					indx ++;
				}
				oper.sem_num = N;
				oper.sem_op = 1;
				oper.sem_flg = 0;

			step3:	ret = semop(sem, &oper, 1);
				if (ret == -1) {
					if (errno == EINTR) goto step3;
					error_handler("semop has failed");
				}
			}
		}
		child[i] = pid;
	}
	ret = sigfillset(&set);
	if (ret == -1) {
		error_handler("sigfillset has failed");
	}
	act.sa_sigaction = SIGINT_handler_main;
	act.sa_mask = set;
	act.sa_flags = 0;

	ret = sigaction(SIGINT, &act, NULL);
	if (ret == -1) {
		error_handler("sigaction has failed");
	}
	printf("Main process is ready to receive strings\n");

	while (1) {
		oper.sem_num = N;
		oper.sem_op = -N;
		oper.sem_flg = 0;

	stepA:	ret = semop(sem, &oper, 1);
		if (ret == -1) {
			if (errno == EINTR) goto stepA;
			error_handler("semop has failed");
		}
	stepB:	ret = scanf("%s", (char*)shm);
		if (ret == -1) {
			if (errno == EINTR) goto stepB;
			error_handler("scanf has failed");
		}
		for(i = 0; i < N; i++) {
			oper.sem_num = i;
                	oper.sem_op = 1;
                	oper.sem_flg = 0;
	stepC:		ret = semop(sem, &oper, 1);
			if (ret == -1) {
				if (errno == EINTR) goto stepC;
				error_handler("semop has failed");
			}
		}
	}
}