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??????????epoll????IO???????????????????????????????if???????????????????????????Reactor?????????epoll???????????????????????????????????????????????????

???????epoll??????

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                #define BUFFER_LENGTH 1024 #define EVENT_SIZE 1024 struct sockitem { int sockfd; int (*callback)(int events, void* arg); char recvbuffer[BUFFER_LENGTH]; char sendbuffer[BUFFER_LENGTH]; }; struct reactor { int epollfd; struct epoll_event events[EVENT_SIZE]; }; struct reactor *g_eventloop = NULL; int recv_cb(int events, void* arg) { if (!(events & EPOLLIN) || arg == NULL) { return -1; } struct sockitem* si = (struct sockitem*)arg; int clientfd = si->sockfd; int epoll_fd = g_eventloop->epollfd; char buffer[BUFFER_LENGTH] = {0}; struct epoll_event ev; int ret = recv(clientfd, buffer, BUFFER_LENGTH, 0); if (ret < 0) { if (errno == EAGAIN || errno == EWOULDBLOCK) { printf("read all data\n"); } close(clientfd); ev.events = EPOLLIN | EPOLLET; //ev->data.fd = clientfd; ev.data.ptr = NULL; free(si); epoll_ctl(epoll_fd, EPOLL_CTL_DEL, clientfd, &ev); } else if (ret == 0) { printf("disconnect clientfd:%d\n", clientfd); close(clientfd); ev.events = EPOLLIN | EPOLLET; //ev->data.fd = clientfd; ev.data.ptr = NULL; free(si); epoll_ctl(epoll_fd, EPOLL_CTL_DEL, clientfd, &ev); return 0; } else { printf("Recv: %s, %d Bytes\n", buffer, ret); ev.events = EPOLLOUT | EPOLLET; si->sockfd = clientfd; si->callback = send_cb; ev.data.ptr = si; epoll_ctl(epoll_fd, EPOLL_CTL_MOD, clientfd, &ev); return 0; } } int send_cb(int events, void* arg) { if (!(events & EPOLLOUT) || arg == NULL) { return -1; } struct sockitem* si = (struct sockitem*)arg; int clientfd = si->sockfd; int epoll_fd = g_eventloop->epollfd; if (send(clientfd, "Hello, you are connected!\n", 26, 0) == -1) { if (errno == EAGAIN || errno == EWOULDBLOCK) { return 0; } perror("send error"); close(clientfd); return -1; } ev.events = EPOLLIN | EPOLLET; si->callback = recv_cb; ev.data.ptr = si; epoll_ctl(epoll_fd, EPOLL_CTL_MOD, clientfd, &ev); return 0; } int accept_cb(int events, void* arg) { if (!(events & EPOLLIN) || arg == NULL) { return -1; } struct sockitem* psi = (struct sockitem*)arg; int epoll_fd = g_eventloop->epollfd; int sockfd = psi->sockfd; struct sockaddr_in client_addr; struct epoll_event ev; 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); if (clientfd <= 0) { return -1; } char str[INET_ADDRSTRLEN] = {0}; struct sockitem* si = (struct sockitem*)malloc(sizeof(struct sockitem)); si->sockfd = clientfd; si->callback = recv_cb; printf("received from %s at port:%d, sockfd:%d, clientfd:%d\n", inet_ntop(AF_INET, &client_addr.sin_addr, str, sizeof(str)), ntohs(client_addr.sin_port), sockfd, clientfd); ev.events = EPOLLIN | EPOLLET; ev.data.ptr = si; epoll_ctl(epoll_fd, EPOLL_CTL_ADD, clientfd, &ev); return 0; } int main(int argc, char* argv[]) { if (argc < 2) { printf("parameter error!\n"); return EXIT_FAILURE; } int port = atoi(argv[1]); int sockfd = socket(AF_INET, SOCK_STREAM, 0); if (sockfd < 0) { return -1; } 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) { exit(EXIT_FAILURE); } printf("start server and wait for connection...\n"); if (listen(sockfd, 5) < 0) { exit(EXIT_FAILURE); } g_eventloop = (struct reactor*)malloc(sizeof(struct reactor)); g_eventloop->epollfd = epoll_create(1); struct epoll_event ev; ev.events = EPOLLIN; struct sockitem* si = (struct sockitem*)malloc(sizeof(struct sockitem)); si->sockfd = sockfd; si->callback = accept_cb; ev.data.ptr = si; epoll_ctl(g_eventloop->epollfd, EPOLL_CTL_ADD, sockfd, &ev); while (1) { int nready = epoll_wait(g_eventloop->epollfd, g_eventloop->events, EVENT_SIZE, -1); if (nready < -1) { break; } int i = 0; for (i = 0; i < nready; i++) { if (g_eventloop->events[i].events & EPOLLIN) { struct sockitem* si = (struct sockitem*)g_eventloop->events[i].data.ptr; if (si && si->callback) { si->callback(g_eventloop->events[i].events, si); } } if (g_eventloop->events[i].events & EPOLLOUT) { struct sockitem* si = (struct sockitem*)g_eventloop->events[i].data.ptr; if (si && si->callback) { si->callback(g_eventloop->events[i].events, si); } } } } close(sockfd); exit(EXIT_SUCCESS); }
              
             
            
           
          
         
        
       
      
     
    
   

???????????epoll_wait????????recv_cb?send_cb???????epoll?????????????????reactor???????????????????????????????????????????