Linux C/C++ 实现TCP服务器

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前言

今天我们主要来实现TCP并发网络编程，有2种方法，分别是一请求一线程的方法，还有一种就是io多路复用epoll的方法。

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提示：以下是本篇文章正文内容，下面案例可供参考

一、TCP网络并发

主要是多个客户端，一个服务器，多个客户端可以发送请求给服务器，服务端接受并显示出来。

我们下面就用2种方法来分别实现这个功能。

二、一请求一线程

代码如下（示例）：

#include 
#include
#include

#include
#include
#include

#include
#include


#define BUFFER_LENGTH		1024
#define EPOLL_SIZE			1024


void* client_routine(void* arg) {

	int clientfd = *(int*)arg;

	while (1) {

		char buffer[BUFFER_LENGTH] = { 0 };
		int len = recv(clientfd, buffer, BUFFER_LENGTH, 0);
		if (len < 0) {
			close(clientfd);
			break;
		}
		else if (len == 0) {
			close(clientfd);
			break;
		}
		else {
			printf("Recv: %s, %d byte(s)\n", buffer, len);
		}
	}
}


int main(int argc,char* argv[]) {

	if (argc < 2) {
		printf("Parm Error\n");
		return -1;
	}

	int port = atoi(argv[1]);

	int sockfd = socket(AF_INET, SOCK_STREAM, 0);

	struct sockaddr_in addr;
	memset(&addr, 0, sizeof(struct sockaddr_in));
	addr.sin_family = AF_INET;
	addr.sin_port = htons(port);
	addr.sin_addr.s_addr = INADDR_ANY;

	if (bind(sockfd, (struct sockaddr*)&addr, sizeof(struct sockaddr_in)) < 0) {
		perror("bind");
		return 2;
	}

	if (listen(sockfd, 5) < 0) {
		perror("listen");
		return 3;
	}


	while (1) {

		struct sockaddr_in client_addr;
		memset(&client_addr, 0, sizeof(struct sockaddr_in));
		socklen_t client_len = sizeof(client_addr);

		int clientfd = accept(sockfd, (struct sockaddr*)&client_addr, &client_len);

		pthread_t thread_id;
		pthread_create(&thread_id, NULL, client_routine, &clientfd);
		
	}
	return 0;
}

三、io多路复用epoll

代码如下（示例）：

#include 
#include
#include

#include
#include
#include

#include
#include

#include




#define BUFFER_LENGTH		1024
#define EPOLL_SIZE			1024



int main(int argc,char* argv[]) {

	if (argc < 2) {
		printf("Parm Error\n");
		return -1;
	}

	int port = atoi(argv[1]);

	int sockfd = socket(AF_INET, SOCK_STREAM, 0);

	struct sockaddr_in addr;
	memset(&addr, 0, sizeof(struct sockaddr_in));
	addr.sin_family = AF_INET;
	addr.sin_port = htons(port);
	addr.sin_addr.s_addr = INADDR_ANY;

	if (bind(sockfd, (struct sockaddr*)&addr, sizeof(struct sockaddr_in)) < 0) {
		perror("bind");
		return 2;
	}

	if (listen(sockfd, 5) < 0) {
		perror("listen");
		return 3;
	}

	int epfd = epoll_create(1);
	struct epoll_event events[EPOLL_SIZE] = { 0 };

	struct epoll_event ev;
	ev.events = EPOLLIN;
	ev.data.fd = sockfd;
	epoll_ctl(epfd, EPOLL_CTL_ADD, sockfd, &ev);


	while (1) {

		int nready = epoll_wait(epfd, events, EPOLL_SIZE, 5);
		if (nready == -1) continue;

		for (int i = 0; i < nready; ++i) {

			if (events[i].data.fd == sockfd) {//listen

				struct sockaddr_in client_addr;
				memset(&client_addr, 0, sizeof(struct sockaddr_in));
				socklen_t client_len = sizeof(client_addr);

				int clientfd = accept(sockfd, (struct sockaddr*)&client_addr, &client_len);

				ev.events = EPOLLIN | EPOLLET;
				ev.data.fd = clientfd;
				epoll_ctl(epfd, EPOLL_CTL_ADD, clientfd, &ev);

			}
			else {

				int clientfd = events[i].data.fd;

				char buffer[BUFFER_LENGTH] = { 0 };
				int len = recv(clientfd, buffer, BUFFER_LENGTH, 0);
				if (len < 0) {
					close(clientfd);
					ev.events = EPOLLIN | EPOLLET;
					ev.data.fd = clientfd;
					epoll_ctl(epfd, EPOLL_CTL_DEL, clientfd, &ev);
				}
				else if (len == 0) {
					close(clientfd);
					ev.events = EPOLLIN | EPOLLET;
					ev.data.fd = clientfd;
					epoll_ctl(epfd, EPOLL_CTL_DEL, clientfd, &ev);
				}
				else {
					printf("Recv: %s, %d byte(s)\n", buffer, len);

				}

			}

		}

	}

	return 0;
}

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总结

今天就主要给大家带来这些内容了，希望大家可以尝试自己去解决这些问题，并且成功实现。

参考资料

C/C++ Linux高级开发课程