【在Linux世界中追寻伟大的One Piece】Socket编程UDP(续)

枫叶丹

发布于 2024-10-31 08:21:23

720

发布于 2024-10-31 08:21:23

文章被收录于专栏：C++

1 -> V3版本-实现简单聊天室

UdpServer.hpp

#pragma once

#include <iostream>
#include <string>
#include <cerrno>
#include <cstring>
#include <unistd.h>
#include <strings.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <functional>
#include <pthread.h>
// #include <mutex>
// #include <condition_variable>
#include "nocopy.hpp"
#include "Log.hpp"
#include "Comm.hpp"
#include "InetAddr.hpp"
#include "ThreadPool.hpp"

const static uint16_t defaultport = 8888;
const static int defaultfd = -1;
const static int defaultsize = 1024;
using task_t = std::function<void()>;

// using cb_t = std::function<std::string(std::string)>; // 定义了一个函数类型
// 聚焦在 IO 上
class UdpServer : public nocopy
{
public:
	// UdpServer(cb_t OnMessage, uint16_t port = defaultport)
	// : _port(port), _sockfd(defaultfd),
	_OnMessage(OnMessage)
		UdpServer(uint16_t port = defaultport) : _port(port),
		_sockfd(defaultfd)
	{
		pthread_mutex_init(&_user_mutex, nullptr);
	}

	void Init()
	{
		// 1. 创建 socket，就是创建了文件细节
		_sockfd = socket(AF_INET, SOCK_DGRAM, 0);
		if (_sockfd < 0)
		{
			lg.LogMessage(Fatal, "socket errr, %d : %s\n", errno,
				strerror(errno));
			exit(Socket_Err);
		}

		lg.LogMessage(Info, "socket success, sockfd: %d\n",
			_sockfd);
		// 2. 绑定，指定网络信息
		struct sockaddr_in local;
		bzero(&local, sizeof(local)); // memset
		local.sin_family = AF_INET;
		local.sin_port = htons(_port);
		local.sin_addr.s_addr = INADDR_ANY; // 0
		// local.sin_addr.s_addr = inet_addr(_ip.c_str()); // 1. 4字节 IP 2. 变成网络序列
		// 结构体填完，设置到内核中了吗？？没有
		int n = ::bind(_sockfd, (struct sockaddr*)&local,
			sizeof(local));
		if (n != 0)
		{
			lg.LogMessage(Fatal, "bind errr, %d : %s\n", errno,
				strerror(errno));
			exit(Bind_Err);
		}

		ThreadPool<task_t>::GetInstance()->Start();
	}

	void AddOnlineUser(InetAddr addr)
	{
		LockGuard lockguard(&_user_mutex);
		for (auto& user : _online_user)
		{
			if (addr == user)
				return;
		}

		_online_user.push_back(addr);
		lg.LogMessage(Debug, "%s:%d is add to onlineuser
			list...\n", addr.Ip().c_str(), addr.Port());
	}

	void Route(int sock, const std::string& message)
	{
		LockGuard lockguard(&_user_mutex);
		for (auto& user : _online_user)
		{
			sendto(sock, message.c_str(), message.size(), 0,
				(struct sockaddr*)&user.GetAddr(), sizeof(user.GetAddr()));
			lg.LogMessage(Debug, "server send message to %s:%d,
				message: % s\n", user.Ip().c_str(), user.Port(), message.c_str());
		}
	}

	void Start()
	{
		// 服务器永远不退出
		char buffer[defaultsize];
		for (;;)
		{
			struct sockaddr_in peer;

			socklen_t len = sizeof(peer); // 不能乱写
			ssize_t n = recvfrom(_sockfd, buffer, sizeof(buffer) -
				1, 0, (struct sockaddr*)&peer, &len);
			if (n > 0)
			{
				InetAddr addr(peer);
				AddOnlineUser(addr);
				buffer[n] = 0;
				std::string message = "[";

				message += addr.Ip();
				message += ":";
				message += std::to_string(addr.Port());
				message += "]# ";
				message += buffer;

				task_t task = std::bind(&UdpServer::Route, this,
					_sockfd, message);
				ThreadPool<task_t>::GetInstance()->Push(task);
				// 处理消息
				// std::string response = _OnMessage(buffer);
				// std::cout << "[" << addr.PrintDebug() << "]# "<< buffer << std::endl;
				// sendto(_sockfd, response.c_str(),
				response.size(), 0, (struct sockaddr*)&peer, len);
			}
		}
	}

	~UdpServer()
	{
		pthread_mutex_destroy(&_user_mutex);
	}

private:
	// std::string _ip; // 后面要调整
	uint16_t _port;
	int _sockfd;
	std::vector<InetAddr> _online_user; // 会被多个线程同时访问的
	pthread_mutex_t _user_mutex;
	// cb_t _OnMessage; // 回调
};

引入线程池

InetAddr.hpp

#pragma once

#include <iostream>
#include <string>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>

class InetAddr
{
public:
	InetAddr(struct sockaddr_in& addr) :_addr(addr)
	{
		_port = ntohs(_addr.sin_port);
		_ip = inet_ntoa(_addr.sin_addr);
	}

	std::string Ip() 
	{ 
		return _ip; 
	}

	uint16_t Port() 
	{ 
		return _port; 
	};

	std::string PrintDebug()
	{
		std::string info = _ip;
		info += ":";
		info += std::to_string(_port); // "127.0.0.1:4444"

		return info;
	}

	const struct sockaddr_in& GetAddr()
	{
		return _addr;
	}

	bool operator == (const InetAddr& addr)
	{
		//other code
		return this->_ip == addr._ip && this->_port == addr._port;
	}

	~InetAddr() {}

private:
	std::string _ip;
	uint16_t _port;
	struct sockaddr_in _addr;
};

在InetAddr中，重载一下==方便对用户是否是同一个进行比较。

UdpClient.hpp

#include <iostream>
#include <cerrno>
#include <cstring>
#include <string>
#include <unistd.h>
#include <sys/types.h> /* See NOTES */
#include <sys/socket.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include "Thread.hpp"
#include "InetAddr.hpp"

void Usage(const std::string& process)
{
	std::cout << "Usage: " << process << " server_ip server_port"
		<< std::endl;
}

class ThreadData
{
public:
	ThreadData(int sock, struct sockaddr_in& server) :
		_sockfd(sock), _serveraddr(server)
	{
	}

	~ThreadData()
	{
	}

public:
	int _sockfd;
	InetAddr _serveraddr;
};

void RecverRoutine(ThreadData& td)
{
	char buffer[4096];
	while (true)
	{
		struct sockaddr_in temp;
		socklen_t len = sizeof(temp);
		ssize_t n = recvfrom(td._sockfd, buffer, sizeof(buffer) -
			1, 0, (struct sockaddr*)&temp, &len); // 一般建议都是要填的.
		if (n > 0)
		{
			buffer[n] = 0;
			std::cerr << buffer << std::endl; // 方便一会查看效果
		}
		else
			break;
	}
}

// 该线程只负责发消息
void SenderRoutine(ThreadData& td)
{
	while (true)
	{
		// 我们要发的数据
		std::string inbuffer;
		std::cout << "Please Enter# ";
		std::getline(std::cin, inbuffer);
		auto server = td._serveraddr.GetAddr();

		// 我们要发给谁呀？server
		ssize_t n = sendto(td._sockfd, inbuffer.c_str(),
			inbuffer.size(), 0, (struct sockaddr*)&server, sizeof(server));
		if (n <= 0)
			std::cout << "send error" << std::endl;
	}
}

// ./udp_client server_ip server_port
int main(int argc, char* argv[])
{
	if (argc != 3)
	{
		Usage(argv[0]);
		return 1;
	}

	std::string serverip = argv[1];
	uint16_t serverport = std::stoi(argv[2]);
	// 1. 创建 socket
	// udp 是全双工的。既可以读，也可以写，可以同时读写，不会多线程读写的问题
	int sock = socket(AF_INET, SOCK_DGRAM, 0);
	if (sock < 0)
	{
		std::cerr << "socket error: " << strerror(errno) <<
			std::endl;

		return 2;
	}

	std::cout << "create socket success: " << sock << std::endl;
	// 2. client 要不要进行 bind? 一定要 bind 的！！但是，不需要显示bind，client 会在首次发送数据的时候会自动进行 bind
	// 为什么？server 端的端口号，一定是众所周知，不可改变的，client 需要 port，bind 随机端口.
	// 为什么？client 会非常多.
	// client 需要 bind，但是不需要显示 bind，让本地 OS 自动随机 bind，选择随机端口号
	// 2.1 填充一下 server 信息
	struct sockaddr_in server;
	memset(&server, 0, sizeof(server));
	server.sin_family = AF_INET;
	server.sin_port = htons(serverport);
	server.sin_addr.s_addr = inet_addr(serverip.c_str());

	ThreadData td(sock, server);
	Thread<ThreadData> recver("recver", RecverRoutine, td);
	Thread<ThreadData> sender("sender", SenderRoutine, td);

	recver.Start();
	sender.Start();
	recver.Join();
	sender.Join();
	close(sock);

	return 0;
}