c++ 使用UDP协议实现广播

短命女 2022-04-23 06:36 378阅读 0赞

文章参考：  
Windows:[https://blog.csdn.net/great3779/article/details/5699986][https_blog.csdn.net_great3779_article_details_5699986]  
稍微替博主整理一下子/哈哈  
Linux: [https://blog.csdn.net/robertkun/article/details/8475843][https_blog.csdn.net_robertkun_article_details_8475843]  
**1. Windows 服务器端**

// 服务器端
    // Server.cpp : Defines the entry point for the console application.
    //
    
    #include "stdafx.h"
    #include <WinSock2.h>
    #include <stdio.h>
    #include <iostream>
    using namespace std;
    
    #pragma comment(lib, "ws2_32.lib")
    
    const int MAX_BUF_LEN = 255;
    
    int _tmain(int argc, _TCHAR* argv[])
    {
        
    	WORD wVersionRequested;
    	WSADATA wsaData;
    	int err;
    
    	// 启动socket api
    	wVersionRequested = MAKEWORD( 2, 2 );
    	err = WSAStartup( wVersionRequested, &wsaData );
    	if ( err != 0 )
    	{
        
    		return -1;
    	}
    
    	if ( LOBYTE( wsaData.wVersion ) != 2 ||
    		HIBYTE( wsaData.wVersion ) != 2 )
    	{
        
    			WSACleanup( );
    			return -1; 
    	}
    
    	// 创建socket
    	SOCKET connect_socket;
    	connect_socket = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
    	if(INVALID_SOCKET == connect_socket)
    	{
        
    		err = WSAGetLastError();
    		printf("/"socket/" error! error code is %d/n", err);
    		return -1;
    	}
    
    	SOCKADDR_IN sin;
    	sin.sin_family = AF_INET;
    	sin.sin_port = htons(3779);
    	sin.sin_addr.s_addr = INADDR_BROADCAST;
    
    	bool bOpt = true;
    	//设置该套接字为广播类型
    	setsockopt(connect_socket, SOL_SOCKET, SO_BROADCAST, (char*)&bOpt, sizeof(bOpt));
    
    	int nAddrLen = sizeof(SOCKADDR);
    
    	char buff[MAX_BUF_LEN] = "";
    	int nLoop = 0;
    	while(1)
    	{
        
    		nLoop++;
    		sprintf(buff, "%8d", nLoop);
    
    		// 发送数据
    		int nSendSize = sendto(connect_socket, buff, strlen(buff), 0, (SOCKADDR*)&sin, nAddrLen);
    		if(SOCKET_ERROR == nSendSize)
    		{
        
    			err = WSAGetLastError();
    			printf("/"sendto/" error!, error code is %d/n", err);
    			return -1;
    		}
    		printf("Send: %s/n", buff);
    		Sleep(500);
    	}
    
    	return 0;
    }

**2. Windows 客户端**

// 客户端
    // Client.cpp : Defines the entry point for the console application.
    //
    
    #include "stdafx.h"
    #include <WinSock2.h>
    #include <stdio.h>
    
    #pragma comment(lib, "ws2_32.lib")
    
    const int MAX_BUF_LEN = 255;
    
    int _tmain(int argc, _TCHAR* argv[])
    {
        
    	WORD wVersionRequested;
    	WSADATA wsaData;
    	int err;
    
    	// 启动socket api
    	wVersionRequested = MAKEWORD( 2, 2 );
    	err = WSAStartup( wVersionRequested, &wsaData );
    	if ( err != 0 )
    	{
        
    		return -1;
    	}
    
    	if ( LOBYTE( wsaData.wVersion ) != 2 ||	HIBYTE( wsaData.wVersion ) != 2 )
    	{
        
    			WSACleanup( );
    			return -1; 
    	}
    
    	// 创建socket
    	SOCKET connect_socket;
    	connect_socket = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
    	if(INVALID_SOCKET == connect_socket)
    	{
        
    		err = WSAGetLastError();
    		printf("/"socket/" error! error code is %d/n", err);
    		return -1;
    	}
    
    	// 用来绑定套接字
    	SOCKADDR_IN sin;
    	sin.sin_family = AF_INET;
    	sin.sin_port = htons(3779);
    	sin.sin_addr.s_addr = 0;
    
    	// 用来从网络上的广播地址接收数据
    	SOCKADDR_IN sin_from;
    	sin_from.sin_family = AF_INET;
    	sin_from.sin_port = htons(3779);
    	sin_from.sin_addr.s_addr = INADDR_BROADCAST;
    
    	//设置该套接字为广播类型，
    	bool bOpt = true;
    	setsockopt(connect_socket, SOL_SOCKET, SO_BROADCAST, (char*)&bOpt, sizeof(bOpt));
    
    	// 绑定套接字
    	err = bind(connect_socket, (SOCKADDR*)&sin, sizeof(SOCKADDR));
    	if(SOCKET_ERROR == err)
    	{
        
    		err = WSAGetLastError();
    		printf("/"bind/" error! error code is %d/n", err);
    		return -1;
    	}
    
    	int nAddrLen = sizeof(SOCKADDR);
    	char buff[MAX_BUF_LEN] = "";
    	int nLoop = 0;
    	while(1)
    	{
        
    		// 接收数据
    		int nSendSize = recvfrom(connect_socket, buff, MAX_BUF_LEN, 0, (SOCKADDR*)&sin_from, &nAddrLen);
    		if(SOCKET_ERROR == nSendSize)
    		{
        
    			err = WSAGetLastError();
    			printf("/"recvfrom/" error! error code is %d/n", err);
    			return -1;
    		}
    		buff[nSendSize] = '/0';
    		printf("Recv: %s/n", buff);
    	}
    
    	return 0;
    }

**3. Linux 客户端**

// 发送端
    #include <iostream>
    #include <stdio.h>
    #include <sys/socket.h>
    #include <unistd.h>
    #include <sys/types.h>
    #include <netdb.h>
    #include <netinet/in.h>
    #include <arpa/inet.h>
    #include <string.h>
     
     
    using namespace std;
     
    int main()
    {
        
    	setvbuf(stdout, NULL, _IONBF, 0); 
    	fflush(stdout); 
     
    	int sock = -1;
    	if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) == -1) 
    	{
           
    		cout<<"socket error"<<endl;	
    		return false;
    	}   
    	
    	const int opt = 1;
    	//设置该套接字为广播类型，
    	int nb = 0;
    	nb = setsockopt(sock, SOL_SOCKET, SO_BROADCAST, (char *)&opt, sizeof(opt));
    	if(nb == -1)
    	{
        
    		cout<<"set socket error..."<<endl;
    		return false;
    	}
     
    	struct sockaddr_in addrto;
    	bzero(&addrto, sizeof(struct sockaddr_in));
    	addrto.sin_family=AF_INET;
    	addrto.sin_addr.s_addr=htonl(INADDR_BROADCAST);
    	addrto.sin_port=htons(6000);
    	int nlen=sizeof(addrto);
     
    	while(1)
    	{
        
    		sleep(1);
    		//从广播地址发送消息
    		char smsg[] = {
        "abcdef"};
    		int ret=sendto(sock, smsg, strlen(smsg), 0, (sockaddr*)&addrto, nlen);
    		if(ret<0)
    		{
        
    			cout<<"send error...."<<ret<<endl;
    		}
    		else
    		{
        		
    			printf("ok ");	
    		}
    	}
     
    	return 0;
    }

**4. Linux 服务器端**

#include <iostream>
    #include <stdio.h>
    #include <sys/socket.h>
    #include <unistd.h>
    #include <sys/types.h>
    #include <netdb.h>
    #include <netinet/in.h>
    #include <arpa/inet.h>
    #include <string.h>
     
     
    using namespace std;
     
    int main()
    {
        
    	setvbuf(stdout, NULL, _IONBF, 0); 
    	fflush(stdout); 
     
    	// 绑定地址
    	struct sockaddr_in addrto;
    	bzero(&addrto, sizeof(struct sockaddr_in));
    	addrto.sin_family = AF_INET;
    	addrto.sin_addr.s_addr = htonl(INADDR_ANY);
    	addrto.sin_port = htons(6000);
    	
    	// 广播地址
    	struct sockaddr_in from;
    	bzero(&from, sizeof(struct sockaddr_in));
    	from.sin_family = AF_INET;
    	from.sin_addr.s_addr = htonl(INADDR_ANY);
    	from.sin_port = htons(6000);
    	
    	int sock = -1;
    	if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) == -1) 
    	{
           
    		cout<<"socket error"<<endl;	
    		return false;
    	}   
     
    	const int opt = 1;
    	//设置该套接字为广播类型，
    	int nb = 0;
    	nb = setsockopt(sock, SOL_SOCKET, SO_BROADCAST, (char *)&opt, sizeof(opt));
    	if(nb == -1)
    	{
        
    		cout<<"set socket error..."<<endl;
    		return false;
    	}
     
    	if(bind(sock,(struct sockaddr *)&(addrto), sizeof(struct sockaddr_in)) == -1) 
    	{
           
    		cout<<"bind error..."<<endl;
    		return false;
    	}
     
    	int len = sizeof(sockaddr_in);
    	char smsg[100] = {
        0};
     
    	while(1)
    	{
        
    		//从广播地址接受消息
    		int ret=recvfrom(sock, smsg, 100, 0, (struct sockaddr*)&from,(socklen_t*)&len);
    		if(ret<=0)
    		{
        
    			cout<<"read error...."<<sock<<endl;
    		}
    		else
    		{
        		
    			printf("%s\t", smsg);	
    		}
     
    		sleep(1);
    	}
     
    	return 0;
    }

[https_blog.csdn.net_great3779_article_details_5699986]: https://blog.csdn.net/great3779/article/details/5699986
[https_blog.csdn.net_robertkun_article_details_8475843]: https://blog.csdn.net/robertkun/article/details/8475843