IOCP模型服务端c++代码

### 回答1：
下面是一个简单的基于IOCP模型的服务端C代码示例：

#include <stdio.h>
#include <stdlib.h>
#include <winsock2.h>
#include <windows.h>

#pragma comment(lib, "ws2_32.lib")

#define MAX_CLIENTS 64
#define BUFFER_SIZE 4096

// 客户端数据结构
typedef struct _CLIENT
{
    SOCKET socket;
    SOCKADDR_IN address;
    OVERLAPPED overlapped;
    WSABUF wsa_buffer;
    char buffer[BUFFER_SIZE];
} CLIENT, *PCLIENT;

// IO操作类型
typedef enum _IO_OPERATION_TYPE
{
    IO_READ,
    IO_WRITE
} IO_OPERATION_TYPE, *PIO_OPERATION_TYPE;

// IO操作数据结构
typedef struct _IO_OPERATION_DATA
{
    IO_OPERATION_TYPE type;
    PCLIENT client;
    DWORD bytes_transferred;
} IO_OPERATION_DATA, *PIO_OPERATION_DATA;

HANDLE completion_port;  // 完成端口句柄
PCLIENT clients[MAX_CLIENTS];  // 客户端数组
int client_count = 0;  // 客户端计数器

// 添加客户端到客户端数组
void add_client(PCLIENT client)
{
    int i;
    for (i = 0; i < MAX_CLIENTS; i++)
    {
        if (clients[i] == NULL)
        {
            clients[i] = client;
            client_count++;
            break;
        }
    }
}

// 从客户端数组中移除客户端
void remove_client(PCLIENT client)
{
    int i;
    for (i = 0; i < MAX_CLIENTS; i++)
    {
        if (clients[i] == client)
        {
            clients[i] = NULL;
            client_count--;
            break;
        }
    }
}

// 异步读取客户端数据
void start_io_read(PCLIENT client)
{
    DWORD flags = 0;
    IO_OPERATION_DATA* io_data = (IO_OPERATION_DATA*)malloc(sizeof(IO_OPERATION_DATA));
    memset(&io_data->overlapped, 0, sizeof(OVERLAPPED));
    io_data->type = IO_READ;
    io_data->client = client;
    io_data->bytes_transferred = 0;
    client->wsa_buffer.buf = client->buffer;
    client->wsa_buffer.len = BUFFER_SIZE;
    WSARecv(client->socket, &client->wsa_buffer, 1, &io_data->bytes_transferred, &flags, &io_data->overlapped, NULL);
}

// 异步写入数据到客户端
void start_io_write(PCLIENT client, char* buffer, int length)
{
    DWORD flags = 0;
    IO_OPERATION_DATA* io_data = (IO_OPERATION_DATA*)malloc(sizeof(IO_OPERATION_DATA));
    memset(&io_data->overlapped, 0, sizeof(OVERLAPPED));
    io_data->type = IO_WRITE;
    io_data->client = client;
    io_data->bytes_transferred = 0;
    client->wsa_buffer.buf = buffer;
    client->wsa_buffer.len = length;
    WSASend(client->socket, &client->wsa_buffer, 1, &io_data->bytes_transferred, flags, &io_data->overlapped, NULL);
}

// 完成端口线程函数
DWORD WINAPI completion_port_thread(LPVOID lpParam)
{
    PIO_OPERATION_DATA io_data;
    PCLIENT client;
    DWORD bytes_transferred;
    DWORD flags;

    while (TRUE)
    {
        if (GetQueuedCompletionStatus(completion_port,  

### 回答2：
IOCP（Input Output Completion Ports）模型是一种高效的异步IO模型，常用于高性能的服务器端开发。

下面是一个基于IOCP模型的服务端C代码的示例：

#include <stdio.h>
#include <stdlib.h>
#include <winsock2.h>
#include <windows.h>

#define MAX_CLIENTS 100
#define BUFFER_SIZE 1024

typedef struct {
OVERLAPPED overlapped;
SOCKET sock;
WSABUF dataBuf;
char buffer[BUFFER_SIZE];
DWORD bytesReceived;
DWORD bytesSent;
} PER_IO_DATA;

DWORD WINAPI WorkerThread(LPVOID lpParam);

int main() {
WSADATA wsaData;
SOCKET listenSock, clientSock;
SOCKADDR_IN serverAddr, clientAddr;
HANDLE hCompletionPort;
DWORD numOfWorkerThreads;
SYSTEM_INFO systemInfo;

// Initialize Winsock
if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0) {
printf("Failed to initialize winsock");
return 1;
}

// Create I/O completion port
hCompletionPort = CreateIoCompletionPort(INVALID_HANDLE_VALUE, NULL, 0, 0);

// Get the number of available worker threads
GetSystemInfo(&systemInfo);
numOfWorkerThreads = systemInfo.dwNumberOfProcessors * 2;

// Create worker threads
for (int i = 0; i < numOfWorkerThreads; i++) {
HANDLE hThread = CreateThread(NULL, 0, WorkerThread, hCompletionPort, 0, NULL);
CloseHandle(hThread);
}

// Create listening socket
listenSock = socket(AF_INET, SOCK_STREAM, 0);

// Bind and listen
serverAddr.sin_family = AF_INET;
serverAddr.sin_addr.s_addr = htonl(INADDR_ANY);
serverAddr.sin_port = htons(8888);
bind(listenSock, (SOCKADDR*)&serverAddr, sizeof(serverAddr));
listen(listenSock, SOMAXCONN);

// Accept incoming connections
while (1) {
int clientAddrSize = sizeof(clientAddr);
clientSock = accept(listenSock, (SOCKADDR*)&clientAddr, &clientAddrSize);

// Associate the client socket with the completion port
CreateIoCompletionPort((HANDLE)clientSock, hCompletionPort, (DWORD)clientSock, 0);

// Create IO operations structure
PER_IO_DATA* perIOData = (PER_IO_DATA*)malloc(sizeof(PER_IO_DATA));
ZeroMemory(perIOData, sizeof(PER_IO_DATA));
perIOData->sock = clientSock;
perIOData->dataBuf.len = BUFFER_SIZE;
perIOData->dataBuf.buf = perIOData->buffer;

// Start asynchronous receiving
DWORD bytesReceived;
if (WSARecv(clientSock, &(perIOData->dataBuf), 1, &bytesReceived, &(perIOData->flags), (LPOVERLAPPED)perIOData, NULL) == SOCKET_ERROR) {
if (WSAGetLastError() != ERROR_IO_PENDING) {
printf("Failed to start WSARecv: %d", WSAGetLastError());
closesocket(clientSock);
free(perIOData);
continue;
}
}
}

// Cleanup
closesocket(listenSock);
WSACleanup();

return 0;
}

DWORD WINAPI WorkerThread(LPVOID lpParam) {
HANDLE hCompletionPort = (HANDLE)lpParam;
DWORD bytesTransferred;
PER_IO_DATA* perIOData;

while (1) {
// Get the next completed IO operation
GetQueuedCompletionStatus(hCompletionPort, &bytesTransferred, (LPDWORD)&perIOData, (LPOVERLAPPED*)&perIOData, INFINITE);

// Handle the completed IO operation
if (bytesTransferred == 0) {
// Client has disconnected
closesocket(perIOData->sock);
free(perIOData);
continue;
}

// Process the received data
// ...

// Start asynchronous sending
DWORD bytesSent;
perIOData->bytesSent = bytesTransferred;
if (WSASend(perIOData->sock, &(perIOData->dataBuf), 1, &bytesSent, 0, (LPOVERLAPPED)perIOData, NULL) == SOCKET_ERROR) {
if (WSAGetLastError() != ERROR_IO_PENDING) {
printf("Failed to start WSASend: %d", WSAGetLastError());
closesocket(perIOData->sock);
free(perIOData);
continue;
}
}

// Start asynchronous receiving for the next data
perIOData->dataBuf.len = BUFFER_SIZE;
perIOData->dataBuf.buf = perIOData->buffer;
DWORD bytesReceived;
if (WSARecv(perIOData->sock, &(perIOData->dataBuf), 1, &bytesReceived, &(perIOData->flags), (LPOVERLAPPED)perIOData, NULL) == SOCKET_ERROR) {
if (WSAGetLastError() != ERROR_IO_PENDING) {
printf("Failed to start WSARecv: %d", WSAGetLastError());
closesocket(perIOData->sock);
free(perIOData);
continue;
}
}
}

return 0;
}

这个示例代码实现了一个使用IOCP模型的服务端，它首先初始化Winsock，并创建一个I/O完成端口。然后，它根据系统中可用的线程数量创建相应数量的工作线程。接下来，它创建一个监听套接字，并绑定到指定的端口上，然后开始接受客户端连接。对于每个连接，它会将客户端套接字与完成端口关联，并开始异步接收数据。在工作线程中，它通过GetQueuedCompletionStatus函数获取完成的I/O操作，然后根据操作类型进行相应的处理。在这个例子中，它处理接收到的数据，并通过异步发送响应。然后，它再次开始异步接收数据，以准备接收下一次请求。

这段代码基于Windows平台，使用了Winsock库来实现网络操作，通过WSARecv和WSASend函数来进行异步IO操作。每个I/O操作都使用了PER_IO_DATA结构体来保存相关的信息，并通过OVERLAPPED结构体进行异步操作的调度。主函数负责创建socket、绑定地址、监听连接等，然后将接受到的连接关联到完成端口并开启异步接收。

总结来说，IOCP模型通过异步IO操作和完成端口机制，能够高效处理并发的网络请求，提供了良好的可扩展性和性能。  

### 回答3：
IOCP（Input/Output Completion Port）模型是一种高效的异步I/O处理模型，它在Windows平台上常用于服务端程序的开发。下面是一个用C语言实现的基本IOCP模型服务端代码，代码如下：

#include <stdio.h>
#include <winsock2.h>

#define MAX_CLIENTS 1000

// 定义一个自定义结构体用于保存每个客户端的信息
typedef struct {
DWORD dwLastBytesRecv; // 上次接收的数据字节数
SOCKET socket; // 客户端套接字
// ...
} CLIENT_INFO;

int main() {
WSADATA wsaData;
if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0) {
printf("WSAStartup failed.\n");
return 1;
}

// 创建套接字
SOCKET listenSocket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
if (listenSocket == INVALID_SOCKET) {
printf("Failed to create socket.\n");
WSACleanup();
return 1;
}

// 绑定套接字到本地地址和端口
sockaddr_in serverAddress;
memset(&serverAddress, 0, sizeof(serverAddress));
serverAddress.sin_family = AF_INET;
serverAddress.sin_addr.s_addr = htonl(INADDR_ANY);
serverAddress.sin_port = htons(12345);

if (bind(listenSocket, (sockaddr*)&serverAddress, sizeof(serverAddress)) == SOCKET_ERROR) {
printf("Failed to bind socket.\n");
closesocket(listenSocket);
WSACleanup();
return 1;
}

// 监听套接字
if (listen(listenSocket, SOMAXCONN) == SOCKET_ERROR) {
printf("Failed to listen.\n");
closesocket(listenSocket);
WSACleanup();
return 1;
}

// 创建完成端口
HANDLE hCompletionPort = CreateIoCompletionPort(INVALID_HANDLE_VALUE, NULL, 0, 0);
if (hCompletionPort == NULL) {
printf("Failed to create completion port.\n");
closesocket(listenSocket);
WSACleanup();
return 1;
}

// 关联监听套接字和完成端口
if (CreateIoCompletionPort((HANDLE)listenSocket, hCompletionPort, 0, 0) == NULL) {
printf("Failed to create completion port association.\n");
CloseHandle(hCompletionPort);
closesocket(listenSocket);
WSACleanup();
return 1;
}

printf("Server started.\n");

// 循环接收客户端连接请求
while (1) {
// 等待客户端连接
sockaddr_in clientAddress;
int clientAddressSize = sizeof(clientAddress);
SOCKET clientSocket = accept(listenSocket, (sockaddr*)&clientAddress, &clientAddressSize);
if (clientSocket == INVALID_SOCKET) {
printf("Failed to accept client.\n");
closesocket(listenSocket);
CloseHandle(hCompletionPort);
WSACleanup();
return 1;
}

// 将新连接的客户端套接字关联到完成端口
if (CreateIoCompletionPort((HANDLE)clientSocket, hCompletionPort, 0, 0) == NULL) {
printf("Failed to create completion port association for client.\n");
closesocket(clientSocket);
closesocket(listenSocket);
CloseHandle(hCompletionPort);
WSACleanup();
return 1;
}

// 创建客户端信息结构体并初始化
CLIENT_INFO* clientInfo = (CLIENT_INFO*)malloc(sizeof(CLIENT_INFO));
if (clientInfo == NULL) {
printf("Failed to allocate memory for client info.\n");
closesocket(clientSocket);
closesocket(listenSocket);
CloseHandle(hCompletionPort);
WSACleanup();
return 1;
}
clientInfo->dwLastBytesRecv = 0;
clientInfo->socket = clientSocket;

// 启动异步接收操作
DWORD dwBytesRecv;
WSABUF dataBuff;
dataBuff.buf = NULL;
dataBuff.len = 0;
DWORD dwFlags = 0;
if (WSARecv(clientSocket, &dataBuff, 1, &dwBytesRecv, &dwFlags, NULL, NULL) == SOCKET_ERROR &&
WSAGetLastError() != WSA_IO_PENDING) {
printf("Failed to start asynchronous receive.\n");
free(clientInfo);
closesocket(clientSocket);
closesocket(listenSocket);
CloseHandle(hCompletionPort);
WSACleanup();
return 1;
}

printf("New client connected.\n");
}

// 清理资源
closesocket(listenSocket);
CloseHandle(hCompletionPort);
WSACleanup();

return 0;
}

这段代码实现了使用IOCP模型的服务端程序，包括创建监听套接字、绑定端口、监听连接、创建完成端口等操作。在接收到客户端连接请求后，将客户端套接字关联到完成端口上，并通过异步I/O的方式进行数据接收操作。

这只是一个基本的示例代码，实际应用中可能会有更多的功能和错误处理。需要注意的是，在使用这段代码时，需要在编译选项中加入 `-lws2_32` 参数，以链接 Windows Sockets 2 库。

希望以上回答对您有所帮助！