/*
 * Copyright (C)2026 kimapr
 *
 * This file is part of fcnatfw.
 *
 * fcnatfw is free software: you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation, either version 3 of the License, or (at your
 * option) any later version.
 *
 * fcnatfw is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
 * Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program. If not, see <https://www.gnu.org/licenses/>.
 *
 */

#include <sys/socket.h>
#include <stdlib.h>
#include <dlfcn.h>

typedef int (*Ftype_socket)(int, int, int);

int socket(int domain, int type, int protocol) {
	static Ftype_socket real_socket = NULL;
	if (!real_socket)
		real_socket = dlsym(RTLD_NEXT, "socket");

	int sock = real_socket(domain, type, protocol);
	if (sock < 0 || !(domain == AF_INET || domain == AF_INET6))
		return sock;

	int optval = 1;
	setsockopt(sock, SOL_SOCKET,
#ifdef SO_REUSEPORT_LB
		SO_REUSEPORT_LB
#else
#ifdef SO_REUSEPORT
		SO_REUSEPORT
#else
#error SO_REUSEPORT is required for operation. Your platform is not supported
#endif
#endif
	, &optval, sizeof(optval));
	return sock;
}