基于 C++ 手写 HTTP 服务器：请求解析与响应构建 | 极客日志

基于 C++ 手写 HTTP 服务器：请求解析与响应构建 | 极客日志

协议名称	协议全称	默认端口	传输层协议	说明
HTTP	超文本传输协议	80	TCP	网页访问（明文）
HTTPS	安全超文本传输协议	443	TCP	加密网页
FTP	文件传输协议	21 / 20	TCP	文件上传下载
TFTP	简单文件传输协议	69	UDP	简单传输
SMTP	邮件发送协议	25	TCP	发送邮件
POP3	邮件接收协议	110	TCP	下载邮件
IMAP	邮件访问协议	143	TCP	管理邮件
DNS	域名系统	53	UDP/TCP	域名解析
DHCP	动态主机配置协议	67 / 68	UDP	自动分配 IP
Telnet	远程登录协议	23	TCP	不安全远程登录
SSH	安全远程登录	22	TCP	加密远程连接
SNMP	网络管理协议	161	UDP	网络设备管理
NTP	网络时间协议	123	UDP	时间同步

http://ip:port/

socket → bind → listen → accept ↓ 创建线程 ↓ read → 解析 → write

char buffer[1024]; ssize_t s = read(sockfd, buffer, sizeof(buffer) - 1);

GET /index.html HTTP/1.1 Host: xxx

std::stringstream ss(req_header[0]); std::string method, url, version; ss >> method >> url >> version;

std::string path; if (url == "/" || url == "/index.html") path = "./wwwroot/index.html"; else path = "./wwwroot" + url;

std::ifstream in(path); while (std::getline(in, line)) { content += line + "\n"; }

std::string response; response = "HTTP/1.0 200 OK\r\n"; response += "Content-Length: " + std::to_string(content.size()) + "\r\n"; response += "Content-Type: text/html\r\n"; response += "\r\n"; response += content;

write(sockfd, response.c_str(), response.size());

if (!in.is_open()) { std::string body = "<h1>404 Not Found</h1>"; response = "HTTP/1.0 404 Not Found\r\n"; response += "Content-Length: " + std::to_string(body.size()) + "\r\n"; response += "Content-Type: text/html\r\n"; response += "\r\n"; response += body; }

#include <iostream>
#include <string>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <arpa/inet.h>
#include <cstring>
enum Err {
    SocketErr = 1,
    BindErr,
    ListenErr
};
class Socket {
public:
    Socket() { }
    void Init() {
        sockfd_ = socket(AF_INET, SOCK_STREAM, 0);
        if (sockfd_ < 0) {
            std::cout << "socket fail!!!" << std::endl;
            exit(SocketErr);
        }
    }
    void Bind(uint16_t port, std::string ip) {
        struct sockaddr_in server;
        memset(&server, 0, sizeof server);
        server.sin_family = AF_INET;
        server.sin_port = htons(port);
        inet_pton(AF_INET, ip.c_str(), &server.sin_addr);
        if (bind(sockfd_, (struct sockaddr *)&server, sizeof server) < 0) {
            std::cout << "bind fail" << std::endl;
            exit(BindErr);
        }
    }
    void Listen() {
        if (listen(sockfd_, 10) < 0) {
            std::cout << "listen fail" << std::endl;
            exit(ListenErr);
        }
    }
    int Accept(uint16_t *client_port, std::string *client_ip) {
        struct sockaddr_in client;
        bzero(&client, sizeof client);
        socklen_t len = sizeof(client);
        int newfd = accept(sockfd_, (struct sockaddr *)&client, &len);
        if (newfd < 0) {
            return -1;
        }
        char ip[64];
        inet_ntop(AF_INET, &client.sin_addr, ip, sizeof ip);
        *client_port = ntohs(client.sin_port);
        *client_ip = ip;
        return newfd;
    }
    bool Connect(uint16_t server_port, std::string server_ip) {
        struct sockaddr_in server;
        bzero(&server, sizeof server);
        server.sin_family = AF_INET;
        server.sin_port = htons(server_port);
        inet_pton(AF_INET, server_ip.c_str(), &server.sin_addr);
        if (connect(sockfd_, (struct sockaddr *)&server, sizeof(server)) < 0) {
            return false;
        }
        return true;
    }
    ~Socket() {
        close(sockfd_);
    }
private:
    int sockfd_;
};

#include <iostream>
#include <unistd.h>
#include "Socket.hpp"
#include <fstream>
#include <vector>
#include <sstream>
const std::string wwwroot = "./wwwroot";
class HttpServer;
class ThreadData {
public:
    ThreadData(int sockfd, HttpServer *ts) : sockfd_(sockfd), ts_(ts) { }
public:
    int sockfd_;
    HttpServer *ts_;
};
class HttpServer {
public:
    HttpServer(uint16_t port, std::string ip) : port_(port), ip_(ip) { }
    void Init() {
        listenfd_.Init();
        listenfd_.Bind(port_, ip_);
        listenfd_.Listen();
    }
    void start() {
        while (1) {
            uint16_t client_port;
            std::string client_ip;
            int sockfd = listenfd_.Accept(&client_port, &client_ip);
            if (sockfd < 0) {
                continue;
            }
            ThreadData *td = new ThreadData(sockfd, this);
            pthread_t tid;
            pthread_create(&tid, nullptr, ThreadRun, td);
        }
    }
    static void *ThreadRun(void *arg) {
        pthread_detach(pthread_self());
        ThreadData *td = (ThreadData *)arg;
        td->ts_->HttpHandler(td->sockfd_);
        delete td;
        return nullptr;
    }
    std::string ReadHtmlContent(std::string &htmlpath) {
        std::string content;
        std::ifstream in(htmlpath.c_str());
        if (!in.is_open()) {
            return "404";
        }
        std::string line;
        while (std::getline(in, line)) {
            content += line;
        }
        in.close();
        return content;
    }
    void HttpHandler(int sockfd) {
        char buffer[1024];
        ssize_t s = read(sockfd, buffer, sizeof buffer - 1);
        std::string request;
        if (s > 0) {
            buffer[s] = 0;
            std::cout << buffer << std::endl;
            request = buffer;
            std::vector<std::string> req_header;
            while (!request.empty()) {
                ssize_t pos = request.find("\r\n", 0);
                if (pos == std::string::npos) {
                    break;
                }
                std::string line = request.substr(0, pos);
                if (line.empty()) {
                    break;
                }
                req_header.push_back(line);
                request.erase(0, pos + 2);
            }
            std::stringstream ss(req_header[0]);
            std::string method;
            std::string url;
            std::string http_version;
            ss >> method >> url >> http_version;
            std::string path = url;
            if (path == "/" || path == "/index.html") {
                path = wwwroot + "/index.html";
            } else {
                path = wwwroot + url;
            }
            std::string text = ReadHtmlContent(path);
            std::string response;
            if (text == "404") {
                std::string body = "<h1>404 Not Found</h1>";
                response = "HTTP/1.0 404 Not Found\r\n";
                response += "Content-Length: " + std::to_string(body.size()) + "\r\n";
                response += "Content-Type: text/html\r\n";
                response += "\r\n";
                response += body;
            } else {
                response = "HTTP/1.0 200 OK\r\n";
                response += "Content-Length: " + std::to_string(text.size()) + "\r\n";
                response += "Content-Type: text/html\r\n";
                response += "\r\n";
                response += text;
            }
            write(sockfd, response.c_str(), response.size());
        }
        close(sockfd);
    }
    ~HttpServer() { }
private:
    Socket listenfd_;
    uint16_t port_;
    std::string ip_;
};
int main(int argc, char *argv[]) {
    uint16_t port = std::stoi(argv[2]);
    std::string ip = argv[1];
    HttpServer *svr = new HttpServer(port, ip);
    svr->Init();
    svr->start();
    return 0;
}

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>index</title>
</head>
<body>
<h1>你是一个好人</h1>
<a href="http://127.0.0.1:8080/a/b/hello.html">下一页</a>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Hello World</title>
</head>
<body>
<h1>祝你幸福</h1>
<a href="http://127.0.0.1:8080/index.html">回到首页</a>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>index</title>
</head>
<body>
<h1>你是一个好人</h1>
<form action="http://127.0.0.1:8080/a/b/hello.html" method="GET">
银行卡账号：<input type="text" name="user"><br>
银行卡密码：<input type="password" name="pass"><br>
<input type="submit" value="登录">
</form>
<a href="http://127.0.0.1:8080/a/b/hello.html">下一页</a>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>index</title>
</head>
<body>
<h1>你是一个好人</h1>
<form action="http://127.0.0.1:8080/a/b/hello.html" method="POST">
银行卡账号：<input type="text" name="user"><br>
银行卡密码：<input type="password" name="pass"><br>
<input type="submit" value="登录">
</form>
<a href="http://127.0.0.1:8080/a/b/hello.html">下一页</a>
</body>
</html>