server：
1 #include <sys/socket.h> 2 #include <sys/epoll.h> 3 #include <netinet/in.h> 4 #include <arpa/inet.h> 5 #include <fcntl.h> 6 #include <unistd.h> 7 #include <stdio.h> 8 #include <errno.h> 9 #include <iostream> 10 #include <string.h> 11 #include <stdlib.h> 12 using namespace std; 13 #define MAX_EVENTS 500 14 struct myevent_s 15 { 16 int fd; 17 void (*call_back)(int fd, int events, void *arg); 18 int events; 19 void *arg; 20 int status; // 1: in epoll wait list, 0 not in 21 char buff[128]; // recv data buffer 22 int len, s_offset; 23 long last_active; // last active time 24 }; 25 // set event 26 void EventSet(myevent_s *ev, int fd, void (*call_back)(int, int, void*), void *arg) 27 { 28 ev->fd = fd; 29 ev->call_back = call_back; 30 ev->events = 0; 31 ev->arg = arg; 32 ev->status = 0; 33 bzero(ev->buff, sizeof(ev->buff)); 34 ev->s_offset = 0; 35 ev->len = 0; 36 ev->last_active = time(NULL); 37 } 38 // add/mod an event to epoll 39 void EventAdd(int epollFd, int events, myevent_s *ev) 40 { 41 struct epoll_event epv = {0, {0}}; 42 int op; 43 epv.data.ptr = ev; 44 epv.events = ev->events = events; 45 if(ev->status == 1){ 46 op = EPOLL_CTL_MOD; 47 } 48 else{ 49 op = EPOLL_CTL_ADD; 50 ev->status = 1; 51 } 52 if(epoll_ctl(epollFd, op, ev->fd, &epv) < 0) 53 printf("Event Add failed[fd=%d], evnets[%d] ", ev->fd, events); 54 else 55 printf("Event Add OK[fd=%d], op=%d, evnets[%0X] ", ev->fd, op, events); 56 } 57 // delete an event from epoll 58 void EventDel(int epollFd, myevent_s *ev) 59 { 60 struct epoll_event epv = {0, {0}}; 61 if(ev->status != 1) return; 62 epv.data.ptr = ev; 63 ev->status = 0; 64 epoll_ctl(epollFd, EPOLL_CTL_DEL, ev->fd, &epv); 65 } 66 int g_epollFd; 67 myevent_s g_Events[MAX_EVENTS+1]; // g_Events[MAX_EVENTS] is used by listen fd 68 void RecvData(int fd, int events, void *arg); 69 void SendData(int fd, int events, void *arg); 70 // accept new connections from clients 71 void AcceptConn(int fd, int events, void *arg) 72 { 73 struct sockaddr_in sin; 74 socklen_t len = sizeof(struct sockaddr_in); 75 int nfd, i; 76 // accept 77 if((nfd = accept(fd, (struct sockaddr*)&sin, &len)) == -1) 78 { 79 if(errno != EAGAIN && errno != EINTR) 80 { 81 } 82 printf("%s: accept, %d", __func__, errno); 83 return; 84 } 85 do 86 { 87 for(i = 0; i < MAX_EVENTS; i++) 88 { 89 if(g_Events[i].status == 0) 90 { 91 break; 92 } 93 } 94 if(i == MAX_EVENTS) 95 { 96 printf("%s:max connection limit[%d].", __func__, MAX_EVENTS); 97 break; 98 } 99 // set nonblocking 100 int iret = 0; 101 if((iret = fcntl(nfd, F_SETFL, O_NONBLOCK)) < 0) 102 { 103 printf("%s: fcntl nonblocking failed:%d", __func__, iret); 104 break; 105 } 106 // add a read event for receive data 107 EventSet(&g_Events[i], nfd, RecvData, &g_Events[i]); 108 EventAdd(g_epollFd, EPOLLIN, &g_Events[i]); 109 }while(0); 110 printf("new conn[%s:%d][time:%d], pos[%d] ", inet_ntoa(sin.sin_addr), 111 ntohs(sin.sin_port), g_Events[i].last_active, i); 112 } 113 // receive data 114 void RecvData(int fd, int events, void *arg) 115 { 116 struct myevent_s *ev = (struct myevent_s*)arg; 117 int len; 118 // receive data 119 len = recv(fd, ev->buff+ev->len, sizeof(ev->buff)-1-ev->len, 0); 120 EventDel(g_epollFd, ev); 121 if(len > 0) 122 { 123 ev->len += len; 124 ev->buff[ev->len] = ' '; 125 printf("C[%d]:%s ", fd, ev->buff); 126 // change to send event 127 EventSet(ev, fd, SendData, ev); 128 EventAdd(g_epollFd, EPOLLOUT, ev); 129 } 130 else if(len == 0) 131 { 132 close(ev->fd); 133 printf("[fd=%d] pos[%d], closed gracefully. ", fd, ev-g_Events); 134 } 135 else 136 { 137 close(ev->fd); 138 printf("recv[fd=%d] error[%d]:%s ", fd, errno, strerror(errno)); 139 } 140 } 141 // send data 142 void SendData(int fd, int events, void *arg) 143 { 144 struct myevent_s *ev = (struct myevent_s*)arg; 145 int len; 146 // send data 147 sprintf(ev->buff, "callback"); 148 ev->len = strlen(ev->buff); 149 len = send(fd, ev->buff + ev->s_offset, ev->len - ev->s_offset, 0); 150 if(len > 0) 151 { 152 printf("send[fd=%d], [%d<->%d]%s ", fd, len, ev->len, ev->buff); 153 ev->s_offset += len; 154 if(ev->s_offset == ev->len) 155 { 156 // change to receive event 157 EventDel(g_epollFd, ev); 158 EventSet(ev, fd, RecvData, ev); 159 EventAdd(g_epollFd, EPOLLIN, ev); 160 } 161 } 162 else 163 { 164 close(ev->fd); 165 EventDel(g_epollFd, ev); 166 printf("send[fd=%d] error[%d]:%s ", fd, errno, strerror(errno)); 167 } 168 } 169 void InitListenSocket(int epollFd, short port) 170 { 171 int listenFd = socket(AF_INET, SOCK_STREAM, 0); 172 fcntl(listenFd, F_SETFL, O_NONBLOCK); // set non-blocking 173 printf("server listen fd=%d ", listenFd); 174 EventSet(&g_Events[MAX_EVENTS], listenFd, AcceptConn, &g_Events[MAX_EVENTS]); 175 // add listen socket 176 EventAdd(epollFd, EPOLLIN, &g_Events[MAX_EVENTS]); 177 // bind & listen 178 sockaddr_in sin; 179 bzero(&sin, sizeof(sin)); 180 sin.sin_family = AF_INET; 181 sin.sin_addr.s_addr = INADDR_ANY; 182 sin.sin_port = htons(port); 183 bind(listenFd, (const sockaddr*)&sin, sizeof(sin)); 184 listen(listenFd, 5); 185 } 186 int main(int argc, char **argv) 187 { 188 unsigned short port = 12345; // default port 189 if(argc == 2){ 190 port = atoi(argv[1]); 191 } 192 // create epoll 193 g_epollFd = epoll_create(MAX_EVENTS); 194 if(g_epollFd <= 0) printf("create epoll failed.%d ", g_epollFd); 195 // create & bind listen socket, and add to epoll, set non-blocking 196 InitListenSocket(g_epollFd, port); 197 // event loop 198 struct epoll_event events[MAX_EVENTS]; 199 printf("server running:port[%d] ", port); 200 int checkPos = 0; 201 while(1){ 202 // a simple timeout check here, every time 100, better to use a mini-heap, and add timer event 203 long now = time(NULL); 204 for(int i = 0; i < 100; i++, checkPos++) // doesn't check listen fd 205 { 206 if(checkPos == MAX_EVENTS) checkPos = 0; // recycle 207 if(g_Events[checkPos].status != 1) continue; 208 long duration = now - g_Events[checkPos].last_active; 209 if(duration >= 60) // 60s timeout 210 { 211 close(g_Events[checkPos].fd); 212 printf("[fd=%d] timeout[%d--%d]. ", g_Events[checkPos].fd, g_Events[checkPos].last_active, now); 213 EventDel(g_epollFd, &g_Events[checkPos]); 214 } 215 } 216 // wait for events to happen 217 int fds = epoll_wait(g_epollFd, events, MAX_EVENTS, 1000); 218 if(fds < 0){ 219 printf("epoll_wait error, exit "); 220 break; 221 } 222 for(int i = 0; i < fds; i++){ 223 myevent_s *ev = (struct myevent_s*)events[i].data.ptr; 224 if((events[i].events&EPOLLIN)&&(ev->events&EPOLLIN)) // read event 225 { 226 ev->call_back(ev->fd, events[i].events, ev->arg); 227 } 228 if((events[i].events&EPOLLOUT)&&(ev->events&EPOLLOUT)) // write event 229 { 230 ev->call_back(ev->fd, events[i].events, ev->arg); 231 } 232 } 233 } 234 // free resource 235 return 0; 236 }
client：
1 /************************************************************************* 2 > File Name: epoll_echo_client.cpp 3 > Author: 4 > Mail: 5 > Created Time: Tue 05 Dec 2017 04:53:44 PM CST 6 ************************************************************************/ 7 8 #include<iostream> 9 using namespace std; 10 11 #include<stdio.h> 12 #include<stdlib.h> 13 #include<string.h> 14 #include<errno.h> 15 #include<sys/types.h> 16 #include<sys/socket.h> 17 #include<netinet/in.h> 18 #include<arpa/inet.h> 19 #include<unistd.h> 20 21 #define MAXLINE 4096 22 23 24 int main(int argc, char** argv) 25 { 26 int sockfd, n,rec_len; 27 char recvline[4096], sendline[4096]; 28 char buf[MAXLINE]; 29 struct sockaddr_in servaddr; 30 char* ip = "127.0.0.1"; 31 int port = 12345; 32 33 if( (sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0 ){ 34 printf("create socket error: %s(errno: %d) ", strerror(errno),errno); 35 exit(0); 36 } 37 38 39 memset(&servaddr, 0, sizeof(servaddr)); 40 servaddr.sin_family = AF_INET; 41 servaddr.sin_port = htons(port); 42 if( inet_pton(AF_INET, ip, &servaddr.sin_addr) <= 0 ){ 43 printf("inet_pton error for %s ",ip); 44 exit(0); 45 } 46 47 48 if( connect(sockfd, (struct sockaddr*)&servaddr, sizeof(servaddr)) < 0 ){ 49 printf("connect error: %s(errno: %d) ",strerror(errno),errno); 50 exit(0); 51 } 52 53 54 printf("send msg to server: "); 55 fgets(sendline, 4096, stdin); 56 if( send(sockfd, sendline, strlen(sendline), 0) < 0 ) 57 { 58 printf("send msg error: %s(errno: %d) ", strerror(errno), errno); 59 exit(0); 60 } 61 if((rec_len = recv(sockfd, buf, MAXLINE,0)) == -1) { 62 perror("recv error"); 63 exit(1); 64 } 65 buf[rec_len] = ' '; 66 printf("Received : %s ",buf); 67 close(sockfd); 68 exit(0); 69 }
