c++ 实现netty

C++并没有直接实现类似于Netty的网络编程框架，但是可以使用C++的网络库来实现类似的功能。以下是一个简单的示例，展示了如何使用C++的网络库来实现一个简单的服务器和客户端：

服务器端代码：

#include <iostream>
#include <cstring>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <unistd.h>

int main() {
    int serverSocket, clientSocket;
    struct sockaddr_in serverAddr, clientAddr;
    char buffer[1024];

    // 创建socket
    serverSocket = socket(AF_INET, SOCK_STREAM, 0);
    if (serverSocket == -1) {
        std::cerr << "Failed to create socket" << std::endl;
        return -1;
    }

    // 设置服务器地址
    serverAddr.sin_family = AF_INET;
    serverAddr.sin_port = htons(8888);
    serverAddr.sin_addr.s_addr = INADDR_ANY;

    // 绑定socket到指定地址和端口
    if (bind(serverSocket, (struct sockaddr *)&serverAddr, sizeof(serverAddr)) < 0) {
        std::cerr << "Failed to bind socket" << std::endl;
        return -1;
    }

    // 监听连接
    if (listen(serverSocket, 3) < 0) {
        std::cerr << "Failed to listen" << std::endl;        return -1;
    }

    std::cout << "Server started, waiting for connections..." << std::endl;

    // 接受连接
    socklen_t clientAddrLen = sizeof(clientAddr);
    clientSocket = accept(serverSocket, (struct sockaddr *)&clientAddr, &clientAddrLen);
    if (clientSocket < 0) {
        std::cerr << "Failed to accept connection" << std::endl;
        return -1;
    }

    std::cout << "Client connected" << std::endl;

    // 接收和发送数据
    while (true) {
        memset(buffer, 0, sizeof(buffer));
        int bytesRead = read(clientSocket, buffer, sizeof(buffer));
        if (bytesRead < 0) {
            std::cerr << "Failed to read data" << std::endl;
            break;
        }
        if (bytesRead == 0) {
            std::cout << "Client disconnected" << std::endl;
            break;
        }
        std::cout << "Received: " << buffer << std::endl;

        std::string response = "Hello from server";
        if (write(clientSocket, response.c_str(), response.length()) < 0) {
            std::cerr << "Failed to send response" << std::endl;
            break;
        }
    }

    // 关闭连接和socket
    close(clientSocket);
    close(serverSocket);

    return 0;
}

客户端代码：

#include <iostream>
#include <cstring>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <unistd.h>

int main() {
    int clientSocket;
    struct sockaddr_in serverAddr;
    char buffer[1024];

    // 创建socket
    clientSocket = socket(AF_INET, SOCK_STREAM, 0);
    if (clientSocket == -1) {
        std::cerr << "Failed to create socket" << std::endl;
        return -1;
    }

    // 设置服务器地址
    serverAddr.sin_family = AF_INET;
    serverAddr.sin_port = htons(8888);
    if (inet_pton(AF_INET, "127.0.0.1", &(serverAddr.sin_addr)) <= 0) {
        std::cerr << "Invalid address" << std::endl;
        return -1;
    }

    // 连接服务器
    if (connect(clientSocket, (struct sockaddr *)&serverAddr, sizeof(serverAddr)) < 0) {
        std::cerr << "Failed to connect to server" << std::endl;
        return -1;
    }

    std::cout << "Connected to server" << std::endl;

    // 发送和接收数据
    while (true) {
        std::string message;
        std::cout << "Enter message: ";
        std::getline(std::cin, message);

        if (write(clientSocket, message.c_str(), message.length()) < 0) {
            std::cerr << "Failed to send message" << std::endl;
            break;
        }

        memset(buffer, 0, sizeof(buffer));
        int bytesRead = read(clientSocket, buffer, sizeof(buffer));
        if (bytesRead < 0) {
            std::cerr << "Failed to read data" << std::endl;
            break;
        }
        if (bytesRead == 0) {
            std::cout << "Server disconnected" << std::endl;
            break;
        }
        std::cout << "Received: " << buffer << std::endl;
    }

    // 关闭连接和socket
    close(clientSocket);

    return 0;
}

这个示例使用了C++的socket编程库来实现一个简单的服务器和客户端。服务器通过创建socket、绑定地址和端口、监听连接、接受连接、接收和发送数据来实现。客户端通过创建socket、设置服务器地址、连接服务器、发送和接收数据来实现。你可以根据自己的需求进行修改和扩展。