Bu tarz basit bir sunucu-istemci iletişimi (socket communication) ile pek çok uygulama geliştirilebilir. (Hastane, kütüphane, vsvs.) Bu mevcut kod yapısı, yalnızca bağlantı kurulumu ve doğrulama işlemlerini gösterdiği için çok temel düzeyde kalmaktadır ve gerçek bir uygulama gibi kullanılabilmesi için kod yapısının geliştirilmesi gerekmektedir.
SimpleServer:
CXX=g++
CXXFLAGS=- std=c++11 -Wall -O2
all: simple_server
simple_server: simple_server.o
$(CXX) $(CXXFLAGS) -o simple_server simple_server.o
simple_server.o: simple_server.cpp packet.h
$(CXX) $(CXXFLAGS) -c simple_server.cpp
clean:
rm -f simple_server.o simple_server
.PHONY: all clean
packet.h:
#ifndef METIN2_SIMPLE_PACKET_H
#define METIN2_SIMPLE_PACKET_H
#include <cstdint>
enum PacketHeader : uint8_t {
HEADER_CG_HANDSHAKE = 0xff,
HEADER_GC_HANDSHAKE = 0xff
};
#pragma pack(push, 1)
struct TPacketCGHandshake {
uint8_t bHeader;
uint32_t dwHandshake;
uint32_t dwTime;
int32_t lDelta;
};
struct TPacketGCHandshake {
uint8_t bHeader;
uint32_t dwHandshake;
uint32_t dwTime;
int32_t lDelta;
};
#pragma pack(pop)
#endif // METIN2_SIMPLE_PACKET_H
simple_server.cpp:
#include "packet.h"
#include <iostream>
#include <sys/socket.h>
#include <netinet/in.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <cstdlib>
#include <ctime>
#include <cstring>
uint32_t get_dword_time() {
return static_cast<uint32_t>(time(nullptr));
}
int main() {
srand(static_cast<unsigned int>(time(nullptr)));
int server_fd = socket(AF_INET, SOCK_STREAM, 0);
if (server_fd == -1) {
perror("socket");
return 1;
}
int opt = 1;
setsockopt(server_fd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
sockaddr_in addr{};
addr.sin_family = AF_INET;
addr.sin_addr.s_addr = INADDR_ANY;
addr.sin_port = htons(13000);
if (bind(server_fd, reinterpret_cast<sockaddr*>(&addr), sizeof(addr)) == -1) {
perror("bind");
return 1;
}
if (listen(server_fd, 5) == -1) {
perror("listen");
return 1;
}
std::cout << "Simple server started on port 13000\n";
while (true) {
sockaddr_in client_addr{};
socklen_t client_len = sizeof(client_addr);
int client_fd = accept(server_fd, reinterpret_cast<sockaddr*>(&client_addr), &client_len);
if (client_fd == -1) {
perror("accept");
continue;
}
std::cout << "Client connected: " << inet_ntoa(client_addr.sin_addr) << std::endl;
uint32_t handshake = static_cast<uint32_t>(rand());
TPacketGCHandshake out_packet{};
out_packet.bHeader = HEADER_GC_HANDSHAKE;
out_packet.dwHandshake = handshake;
out_packet.dwTime = get_dword_time();
out_packet.lDelta = 0;
if (send(client_fd, &out_packet, sizeof(out_packet), 0) != sizeof(out_packet)) {
std::cerr << "Failed to send handshake" << std::endl;
close(client_fd);
continue;
}
TPacketCGHandshake in_packet{};
ssize_t received = recv(client_fd, &in_packet, sizeof(in_packet), 0);
if (received != sizeof(in_packet)) {
std::cerr << "Invalid handshake size" << std::endl;
close(client_fd);
continue;
}
if (in_packet.bHeader != HEADER_CG_HANDSHAKE || in_packet.dwHandshake != handshake) {
std::cerr << "Handshake mismatch" << std::endl;
close(client_fd);
continue;
}
std::cout << "Handshake successful" << std::endl;
const char msg[] = "Welcome to the Metin2-like server!\n";
send(client_fd, msg, sizeof(msg) - 1, 0);
close(client_fd);
}
close(server_fd);
return 0;
}
