Linux C/C++百万并发的服务器

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前言

具体内容看上一篇，这篇主要是代码的改进。
链接地址： 实现TCP服务器

一、服务器端代码

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#include <netinet/tcp.h>
#include <arpa/inet.h>
#include <pthread.h>

#include <errno.h>
#include <fcntl.h>

#include <sys/epoll.h>

#define BUFFER_LENGTH		1024
#define EPOLL_SIZE			1024

#define MAX_PORT			100

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) { // disconnect
			close(clientfd);
			break;
		} else {
			printf("Recv: %s, %d byte(s)\n", buffer, len);
		}

	}

}


int islistenfd(int fd, int *fds) {

	int i = 0;
	for (i = 0;i < MAX_PORT;i ++) {
		if (fd == *(fds+i)) return fd;
	}

	return 0;
}

// ./tcp_server 

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

	if (argc < 2) {
		printf("Param Error\n");
		return -1;
	}
	
	int port = atoi(argv[1]); // start 
	int sockfds[MAX_PORT] = {0}; // listen fd
	int epfd = epoll_create(1);  

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

		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+i); // 8888 8889 8890 8891 .... 8987
		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;
		}
		printf("tcp server listen on port : %d\n", port + i);

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

		sockfds[i] = sockfd;
	}
	// 

#if 0

	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);

	}
	
#else

	
	struct epoll_event events[EPOLL_SIZE] = {0};

	while (1) {

		int nready = epoll_wait(epfd, events, EPOLL_SIZE, 5); // -1, 0, 5
		if (nready == -1) continue;

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

			int sockfd = islistenfd(events[i].data.fd, sockfds);
			if (sockfd) { // listen 2

				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);

				fcntl(clientfd, F_SETFL, O_NONBLOCK);

				int reuse = 1;
				setsockopt(clientfd, SOL_SOCKET, SO_REUSEADDR, (char *)&reuse, sizeof(reuse));

				struct epoll_event ev;
				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);

					struct epoll_event ev;
					ev.events = EPOLLIN; 
					ev.data.fd = clientfd;
					epoll_ctl(epfd, EPOLL_CTL_DEL, clientfd, &ev);
					
				} else if (len == 0) { // disconnect
					close(clientfd);

					struct epoll_event ev;
					ev.events = EPOLLIN; 
					ev.data.fd = clientfd;
					epoll_ctl(epfd, EPOLL_CTL_DEL, clientfd, &ev);
					
				} else {
					printf("Recv: %s, %d byte(s), clientfd: %d\n", buffer, len, clientfd);
				}
				
				
			}

		}

	}
	

#endif
	
	return 0;
}

二、客户端代码

代码如下（示例）：

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#include <sys/types.h>
#include <sys/socket.h>
#include <sys/epoll.h>
#include <errno.h>
#include <netinet/tcp.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <fcntl.h>


#define MAX_BUFFER		128
#define MAX_EPOLLSIZE	(384*1024)
#define MAX_PORT		100

#define TIME_SUB_MS(tv1, tv2)  ((tv1.tv_sec - tv2.tv_sec) * 1000 + (tv1.tv_usec - tv2.tv_usec) / 1000)

int isContinue = 0;

static int ntySetNonblock(int fd) {
	int flags;

	flags = fcntl(fd, F_GETFL, 0);
	if (flags < 0) return flags;
	flags |= O_NONBLOCK;
	if (fcntl(fd, F_SETFL, flags) < 0) return -1;
	return 0;
}

static int ntySetReUseAddr(int fd) {
	int reuse = 1;
	return setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, (char *)&reuse, sizeof(reuse));
}



int main(int argc, char **argv) {
	if (argc <= 2) {
		printf("Usage: %s ip port\n", argv[0]);
		exit(0);
	}

	const char *ip = argv[1];
	int port = atoi(argv[2]);
	int connections = 0;
	char buffer[128] = {0};
	int i = 0, index = 0;

	struct epoll_event events[MAX_EPOLLSIZE];
	
	int epoll_fd = epoll_create(MAX_EPOLLSIZE);
	
	strcpy(buffer, " Data From MulClient\n");
		
	struct sockaddr_in addr;
	memset(&addr, 0, sizeof(struct sockaddr_in));
	
	addr.sin_family = AF_INET;
	addr.sin_addr.s_addr = inet_addr(ip);

	struct timeval tv_begin;
	gettimeofday(&tv_begin, NULL);

	while (1) {
		if (++index >= MAX_PORT) index = 0;
		
		struct epoll_event ev;
		int sockfd = 0;

		if (connections < 340000 && !isContinue) {
			sockfd = socket(AF_INET, SOCK_STREAM, 0);
			if (sockfd == -1) {
				perror("socket");
				goto err;
			}

			//ntySetReUseAddr(sockfd);
			addr.sin_port = htons(port+index);

			if (connect(sockfd, (struct sockaddr*)&addr, sizeof(struct sockaddr_in)) < 0) {
				perror("connect");
				goto err;
			}
			ntySetNonblock(sockfd);
			ntySetReUseAddr(sockfd);

			sprintf(buffer, "Hello Server: client --> %d\n", connections);
			send(sockfd, buffer, strlen(buffer), 0);

			ev.data.fd = sockfd;
			ev.events = EPOLLIN | EPOLLOUT;
			epoll_ctl(epoll_fd, EPOLL_CTL_ADD, sockfd, &ev);
		
			connections ++;
		}
		//connections ++;
		if (connections % 1000 == 999 || connections >= 340000) {
			struct timeval tv_cur;
			memcpy(&tv_cur, &tv_begin, sizeof(struct timeval));
			
			gettimeofday(&tv_begin, NULL);

			int time_used = TIME_SUB_MS(tv_begin, tv_cur);
			printf("connections: %d, sockfd:%d, time_used:%d\n", connections, sockfd, time_used);

			int nfds = epoll_wait(epoll_fd, events, connections, 100);
			for (i = 0;i < nfds;i ++) {
				int clientfd = events[i].data.fd;

				if (events[i].events & EPOLLOUT) {
					sprintf(buffer, "data from %d\n", clientfd);
					send(sockfd, buffer, strlen(buffer), 0);
				} else if (events[i].events & EPOLLIN) {
					char rBuffer[MAX_BUFFER] = {0};				
					ssize_t length = recv(sockfd, rBuffer, MAX_BUFFER, 0);
					if (length > 0) {
						printf(" RecvBuffer:%s\n", rBuffer);

						if (!strcmp(rBuffer, "quit")) {
							isContinue = 0;
						}
						
					} else if (length == 0) {
						printf(" Disconnect clientfd:%d\n", clientfd);
						connections --;
						close(clientfd);
					} else {
						if (errno == EINTR) continue;

						printf(" Error clientfd:%d, errno:%d\n", clientfd, errno);
						close(clientfd);
					}
				} else {
					printf(" clientfd:%d, errno:%d\n", clientfd, errno);
					close(clientfd);
				}
			}
		}

		usleep(1 * 1000);
	}

	return 0;

err:
	printf("error : %s\n", strerror(errno));
	return 0;
	
}

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总结

今天主要就是实现这些功能了，可以让服务器的运行量更大。

参考资料

C/C++ Linux高级开发课程