一个完整的稳定的,单线程的,有正确的收发功能的使用epoll的socket服务程序

去年纠结了很久,找了很多代码,也很了很多很多代码,也用了libevent,中间还转了python,都没有能实现一个支持高并发的socket服务程序

 

下面的代码已经在在线环境测试了8天了,负载可以忽略,贡献出来,给我一样曾经迷惑的人:

 

其中不少是借鉴的某大侠的代码,只是不记得地址了,就不写了

 

#include <stdio.h> #include <unistd.h> #include <string.h> #include <stdlib.h> #include <sys/epoll.h> #include <sys/types.h> #include <sys/socket.h> #include <arpa/inet.h> #include <fcntl.h> #include <errno.h> #include <sys/wait.h> #define PORT 3457 #define BACKLOG 100 #define BUF_EV_LEN 150 #define MAX_EPOLL_FD 8000 static char *policyXML="<cross-domain-policy><allow-access-from domain=/"*/" to-ports=/"*/"/></cross-domain-policy>"; static char *policeRequestStr="<policy-file-request/>"; int CreateTcpListenSocket(); int InitEpollFd(); void UseConnectFd(int sockfd); void setnonblocking(int sock); static int listenfd; int main() { signal(SIGPIPE, SIG_IGN); /**/pid_t pid; if((pid = fork()) < 0){ printf("End at: %d",__LINE__); exit(-1); } if (pid){ printf("End at: %d",__LINE__); exit(0); } run(); } int run(){ int epoll_fd; int nfds; int i; struct epoll_event events[BUF_EV_LEN]; struct epoll_event tempEvent; int sockConnect; struct sockaddr_in remoteAddr; int addrLen; addrLen = sizeof(struct sockaddr_in); epoll_fd = InitEpollFd(); if (epoll_fd == -1) { perror("init epoll fd error."); printf("End at: %d",__LINE__); exit(1); } printf("begin in loop./n"); while (1) { nfds = epoll_wait(epoll_fd, events, BUF_EV_LEN, 1000); //sleep(3); if(nfds>5) printf("connect num: %d/n", nfds); if (nfds == -1) { printf("End at: %d",__LINE__); perror("epoll_wait error."); continue; } for (i = 0; i < nfds; i++) { if (listenfd == events[i].data.fd) { //printf("connected success/n"); sockConnect = accept(events[i].data.fd, (struct sockaddr*)&remoteAddr, &addrLen); if (sockConnect == -1) { printf("End at: %d",__LINE__); perror("accept error."); continue; } setnonblocking(sockConnect); tempEvent.events = EPOLLIN | EPOLLET; tempEvent.data.fd = sockConnect; if (epoll_ctl(epoll_fd, EPOLL_CTL_ADD, sockConnect, &tempEvent) < 0) { perror("epoll ctl error."); printf("End at: %d",__LINE__); return -1; } } else { UseConnectFd(events[i].data.fd); } } } printf("---------------------------------/n/n"); } int CreateTcpListenSocket() { int sockfd; struct sockaddr_in localAddr; if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) { perror("create socket fail"); printf("End at: %d",__LINE__); return -1; } setnonblocking(sockfd); bzero(&localAddr, sizeof(localAddr)); localAddr.sin_family = AF_INET; localAddr.sin_port = htons(PORT); localAddr.sin_addr.s_addr = htonl(INADDR_ANY); unsigned int optval; //设置SO_REUSEADDR选项(服务器快速重起) optval = 0x1; setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &optval, 4); /* //设置SO_LINGER选项(防范CLOSE_WAIT挂住所有套接字) optval1.l_onoff = 0; optval1.l_linger = 1; setsockopt(listener, SOL_SOCKET, SO_LINGER, &optval1, sizeof(struct linger)); int nRecvBuf=320*1024;//设置为320K setsockopt(listener ,SOL_SOCKET, SO_RCVBUF,(const char*)&nRecvBuf,sizeof(int)); int nSendBuf=1024*1024;//设置为640K setsockopt(listener ,SOL_SOCKET, SO_SNDBUF,(const char*)&nSendBuf,sizeof(int)); */ if (bind(sockfd, (struct sockaddr*)&localAddr, sizeof(struct sockaddr)) == -1) { perror("bind error"); printf("End at: %d",__LINE__); return -1; } if (listen(sockfd, BACKLOG) == -1) { perror("listen error"); printf("End at: %d",__LINE__); return -1; } return sockfd; } int InitEpollFd() { struct rlimit rt; rt.rlim_max = rt.rlim_cur = MAX_EPOLL_FD; if (setrlimit(RLIMIT_NOFILE, &rt) == -1) { //perror("setrlimit"); printf("<br/> RLIMIT_NOFILE set FAILED: %s <br/>",strerror(errno)); //exit(1); } else { printf("设置系统资源参数成功！/n"); } //epoll descriptor int s_epfd; struct epoll_event ev; listenfd = CreateTcpListenSocket(); if (listenfd == -1) { perror("create tcp listen socket error"); printf("End at: %d",__LINE__); return -1; } s_epfd = epoll_create(MAX_EPOLL_FD); ev.events = EPOLLIN; ev.data.fd = listenfd; if (epoll_ctl(s_epfd, EPOLL_CTL_ADD, listenfd, &ev) < 0) { perror("epoll ctl error"); printf("End at: %d",__LINE__); return -1; } return s_epfd; } void UseConnectFd(int sockfd) { int buffer_size=256; char recvBuff[buffer_size+1]; int recvNum = 0; int buff_size = buffer_size*10; char *buff=calloc(1,buff_size); while(1){ //memset(recvBuff,'/0',buffer_size); recvNum = recv(sockfd, recvBuff, buffer_size, MSG_DONTWAIT); if ( recvNum< 0) { if (errno == ECONNRESET || errno==ETIMEDOUT) {//ETIMEDOUT可能导致SIGPIPE close(sockfd); } break; } else if (recvNum == 0) { close(sockfd); break; } //数据超过预定大小，则重新分配内存 if(recvNum+strlen(buff)>buff_size) { if((buff=realloc(buff,buff_size+strlen(buff)))==NULL) { break; } } recvBuff[recvNum]='/0'; sprintf(buff,"%s%s",buff,recvBuff); //printf("%s/n",recvBuff); if(recvNum<buffer_size) { break; } } if(recvBuff[0]=='0')printf("%s/n",buff); if(strcmp(buff,policeRequestStr)==0) { sendMsg(sockfd, policyXML); }else if(strlen(buff)>0){ sendMsg(sockfd,buff); } free(buff); //printf("message: %s /n", recvBuff); } void setnonblocking(int sock) { int opts; opts=fcntl(sock,F_GETFL); if(opts<0) { perror("fcntl(sock,GETFL)"); printf("End at: %d",__LINE__); exit(1); } opts = opts|O_NONBLOCK; if(fcntl(sock,F_SETFL,opts)<0) { perror("fcntl(sock,SETFL,opts)"); printf("End at: %d",__LINE__); exit(1); } } //发送消息给某个连接 int sendMsg(int fd,char *msg) { if(fd<1) return 0; while(1){ int l=send(fd,msg,strlen(msg)+1,MSG_DONTWAIT); if(l<0){ if(errno==EPIPE){ printf(">Send pipe error: %d/n",errno); printf("%d will close and removed at line %d!/n",fd,__LINE__); printf(">Send pipe error, %d closed!/n",fd); return -1; } break; } if (l <= strlen(msg)+1) { //printf("消息'%s'发送失败！错误代码是%d，错误信息是'%s'/n", msg, errno, strerror(errno)); //return -1; break; } } return 1; }