C++网络协议实战：从HTTP到WebSocket，面试必考的协议实现与优化全解析引言网络协议是C++程序员的必修课，也是大厂面试的重点考察内容。从HTTP到WebSocket，从TCP到UDP，理解协议的本质和实现方式对于构建高性能网络应用至关重要。本文将深入讲解C++网络协议的实现细节，帮你掌握协议解析与优化的核心技巧。一、HTTP协议实现1.1 HTTP请求解析#includeiostream#includestring#includemap#includesstreamstructHttpRequest{std::string method;std::string path;std::string version;std::mapstd::string,std::stringheaders;std::string body;voidprint()const{std::cout"Method: "methodstd::endl;std::cout"Path: "pathstd::endl;std::cout"Version: "versionstd::endl;std::cout"Headers:"std::endl;for(constauto[k,v]:headers){std::cout" "k": "vstd::endl;}std::cout"Body: "bodystd::endl;}};classHttpParser{public:staticHttpRequestparse(conststd::stringraw){HttpRequest req;std::istringstreamstream(raw);std::string line;// 解析请求行if(std::getline(stream,line)){std::istringstreamlineStream(line);lineStreamreq.methodreq.pathreq.version;}// 解析头部while(std::getline(stream,line)line!="\r"){if(line.empty()||line=="\r")break;size_t pos=line.find(":");if(pos!=std::string::npos){std::string key=line.substr(0,pos);std::string value=line.substr(pos+1);// 去除前后空格value=value.substr(value.find_first_not_of(" "));if(!value.empty()value.back()=='\r')value.pop_back();req.headers[key]=value;}}// 解析bodystd::ostringstream bodyStream;bodyStreamstream.rdbuf();req.body=bodyStream.str();returnreq;}};intmain(){std::string rawRequest="GET /api/users HTTP/1.1\r\n""Host: example.com\r\n""User-Agent: Mozilla/5.0\r\n""Accept: application/json\r\n""\r\n";HttpRequest req=HttpParser::parse(rawRequest);req.print();return0;}1.2 HTTP响应构建#includeiostream#includestring#includemap#includesstreamstructHttpResponse{std::string version="HTTP/1.1";intstatusCode=200;std::string statusText="OK";std::mapstd::string,std::stringheaders;std::string body;std::stringbuild()const{std::ostringstream ss;ssversion" "statusCode" "statusText"\r\n";for(constauto[k,v]:headers){ssk": "v"\r\n";}if(!body.empty()){ss"Content-Length: "body.size()"\r\n";}ss"\r\n";ssbody;returnss.str()