05Linux网络编程基础 ---- 定时器
1. socket的TIMEOUT
#include <sys/types.h> #include <sys/socket.h> #include <netinet/in.h> #include <arpa/inet.h> #include <stdlib.h> #include <assert.h> #include <stdio.h> #include <errno.h> #include <fcntl.h> #include <unistd.h> #include <string.h> int timeout_connect( const char* ip, int port, int time ) { int ret = 0; struct sockaddr_in address; bzero( &address, sizeof( address ) ); address.sin_family = AF_INET; inet_pton( AF_INET, ip, &address.sin_addr ); address.sin_port = htons( port ); int sockfd = socket( PF_INET, SOCK_STREAM, 0 ); assert( sockfd >= 0 ); int flags = fcntl(sockfd, F_GETFL, 0); if (flags < 0) { fprintf(stderr, "Get flags error:%s\n", strerror(errno)); close(sockfd); return -1; } flags |= O_NONBLOCK; // if (fcntl(sockfd, F_SETFL, flags) < 0) { // fprintf(stderr, "Set flags error:%s\n", strerror(errno)); // close(sockfd); // return -1; // } struct timeval timeout; timeout.tv_sec = time; timeout.tv_usec = 0; socklen_t len = sizeof( timeout ); ret = setsockopt( sockfd, SOL_SOCKET, SO_SNDTIMEO, &timeout, len ); assert( ret != -1 ); ret = connect( sockfd, ( struct sockaddr* )&address, sizeof( address ) ); if ( ret == -1 ) { if( errno == EINPROGRESS ) { printf( "connecting timeout\n" ); return -1; } printf( "error occur when connecting to server:%d.\n", errno); return -1; } return sockfd; } int main( int argc, char* argv[] ) { if( argc <= 2 ) { printf( "usage: %s ip_address port_number\n", basename( argv[0] ) ); return 1; } const char* ip = argv[1]; int port = atoi( argv[2] ); int sockfd = timeout_connect( ip, port, 5 ); if ( sockfd < 0 ) { return 1; } return 0; }
2. SIGALRM信号
lst_timer.h
#ifndef LST_TIMER #define LST_TIMER #include <time.h> #define BUFFER_SIZE 64 class util_timer; struct client_data { sockaddr_in address; int sockfd; char buf[ BUFFER_SIZE ]; util_timer* timer; }; class util_timer { public: util_timer() : prev( NULL ), next( NULL ){} public: time_t expire; void (*cb_func)( client_data* ); client_data* user_data; util_timer* prev; util_timer* next; }; class sort_timer_lst { public: sort_timer_lst() : head( NULL ), tail( NULL ) {} ~sort_timer_lst() { util_timer* tmp = head; while( tmp ) { head = tmp->next; delete tmp; tmp = head; } } void add_timer( util_timer* timer ) { if( !timer ) { return; } if( !head ) { head = tail = timer; return; } if( timer->expire < head->expire ) { timer->next = head; head->prev = timer; head = timer; return; } add_timer( timer, head ); } void adjust_timer( util_timer* timer ) { if( !timer ) { return; } util_timer* tmp = timer->next; if( !tmp || ( timer->expire < tmp->expire ) ) { return; } if( timer == head ) { head = head->next; head->prev = NULL; timer->next = NULL; add_timer( timer, head ); } else { timer->prev->next = timer->next; timer->next->prev = timer->prev; add_timer( timer, timer->next ); } } void del_timer( util_timer* timer ) { if( !timer ) { return; } if( ( timer == head ) && ( timer == tail ) ) { delete timer; head = NULL; tail = NULL; return; } if( timer == head ) { head = head->next; head->prev = NULL; delete timer; return; } if( timer == tail ) { tail = tail->prev; tail->next = NULL; delete timer; return; } timer->prev->next = timer->next; timer->next->prev = timer->prev; delete timer; } void tick() { if( !head ) { return; } printf( "timer tick\n" ); time_t cur = time( NULL ); util_timer* tmp = head; while( tmp ) { if( cur < tmp->expire ) { break; } tmp->cb_func( tmp->user_data ); head = tmp->next; if( head ) { head->prev = NULL; } delete tmp; tmp = head; } } private: void add_timer( util_timer* timer, util_timer* lst_head ) { util_timer* prev = lst_head; util_timer* tmp = prev->next; while( tmp ) { if( timer->expire < tmp->expire ) { prev->next = timer; timer->next = tmp; tmp->prev = timer; timer->prev = prev; break; } prev = tmp; tmp = tmp->next; } if( !tmp ) { prev->next = timer; timer->prev = prev; timer->next = NULL; tail = timer; } } private: util_timer* head; util_timer* tail; }; #endif
11-1connect_timeout.cpp
#include <sys/types.h> #include <sys/socket.h> #include <netinet/in.h> #include <arpa/inet.h> #include <assert.h> #include <stdio.h> #include <signal.h> #include <unistd.h> #include <errno.h> #include <string.h> #include <fcntl.h> #include <stdlib.h> #include <sys/epoll.h> #include <pthread.h> #include "lst_timer.h" #define FD_LIMIT 65535 #define MAX_EVENT_NUMBER 1024 #define TIMESLOT 5 static int pipefd[2]; static sort_timer_lst timer_lst; static int epollfd = 0; int setnonblocking( int fd ) { int old_option = fcntl( fd, F_GETFL ); int new_option = old_option | O_NONBLOCK; fcntl( fd, F_SETFL, new_option ); return old_option; } void addfd( int epollfd, int fd ) { epoll_event event; event.data.fd = fd; event.events = EPOLLIN | EPOLLET; epoll_ctl( epollfd, EPOLL_CTL_ADD, fd, &event ); setnonblocking( fd ); } void sig_handler( int sig ) { int save_errno = errno; int msg = sig; send( pipefd[1], ( char* )&msg, 1, 0 ); errno = save_errno; } void addsig( int sig ) { struct sigaction sa; memset( &sa, '\0', sizeof( sa ) ); sa.sa_handler = sig_handler; sa.sa_flags |= SA_RESTART; sigfillset( &sa.sa_mask ); assert( sigaction( sig, &sa, NULL ) != -1 ); } void timer_handler() { timer_lst.tick(); alarm( TIMESLOT ); } void cb_func( client_data* user_data ) { epoll_ctl( epollfd, EPOLL_CTL_DEL, user_data->sockfd, 0 ); assert( user_data ); close( user_data->sockfd ); printf( "close fd %d\n", user_data->sockfd ); } int main( int argc, char* argv[] ) { if( argc <= 2 ) { printf( "usage: %s ip_address port_number\n", basename( argv[0] ) ); return 1; } const char* ip = argv[1]; int port = atoi( argv[2] ); int ret = 0; struct sockaddr_in address; bzero( &address, sizeof( address ) ); address.sin_family = AF_INET; inet_pton( AF_INET, ip, &address.sin_addr ); address.sin_port = htons( port ); int listenfd = socket( PF_INET, SOCK_STREAM, 0 ); assert( listenfd >= 0 ); ret = bind( listenfd, ( struct sockaddr* )&address, sizeof( address ) ); assert( ret != -1 ); ret = listen( listenfd, 5 ); assert( ret != -1 ); epoll_event events[ MAX_EVENT_NUMBER ]; int epollfd = epoll_create( 5 ); assert( epollfd != -1 ); addfd( epollfd, listenfd ); ret = socketpair( PF_UNIX, SOCK_STREAM, 0, pipefd ); assert( ret != -1 ); setnonblocking( pipefd[1] ); addfd( epollfd, pipefd[0] ); // add all the interesting signals here addsig( SIGALRM ); addsig( SIGTERM ); bool stop_server = false; client_data* users = new client_data[FD_LIMIT]; bool timeout = false; alarm( TIMESLOT ); while( !stop_server ) { int number = epoll_wait( epollfd, events, MAX_EVENT_NUMBER, -1 ); if ( ( number < 0 ) && ( errno != EINTR ) ) { printf( "epoll failure\n" ); break; } for ( int i = 0; i < number; i++ ) { int sockfd = events[i].data.fd; if( sockfd == listenfd ) { struct sockaddr_in client_address; socklen_t client_addrlength = sizeof( client_address ); int connfd = accept( listenfd, ( struct sockaddr* )&client_address, &client_addrlength ); addfd( epollfd, connfd ); users[connfd].address = client_address; users[connfd].sockfd = connfd; util_timer* timer = new util_timer; timer->user_data = &users[connfd]; timer->cb_func = cb_func; time_t cur = time( NULL ); timer->expire = cur + 3 * TIMESLOT; users[connfd].timer = timer; timer_lst.add_timer( timer ); } else if( ( sockfd == pipefd[0] ) && ( events[i].events & EPOLLIN ) ) { int sig; char signals[1024]; ret = recv( pipefd[0], signals, sizeof( signals ), 0 ); if( ret == -1 ) { // handle the error continue; } else if( ret == 0 ) { continue; } else { for( int i = 0; i < ret; ++i ) { switch( signals[i] ) { case SIGALRM: { timeout = true; break; } case SIGTERM: { stop_server = true; } } } } } else if( events[i].events & EPOLLIN ) { memset( users[sockfd].buf, '\0', BUFFER_SIZE ); ret = recv( sockfd, users[sockfd].buf, BUFFER_SIZE-1, 0 ); printf( "get %d bytes of client data %s from %d\n", ret, users[sockfd].buf, sockfd ); util_timer* timer = users[sockfd].timer; if( ret < 0 ) { if( errno != EAGAIN ) { cb_func( &users[sockfd] ); if( timer ) { timer_lst.del_timer( timer ); } } } else if( ret == 0 ) { cb_func( &users[sockfd] ); if( timer ) { timer_lst.del_timer( timer ); } } else { //send( sockfd, users[sockfd].buf, BUFFER_SIZE-1, 0 ); if( timer ) { time_t cur = time( NULL ); timer->expire = cur + 3 * TIMESLOT; printf( "adjust timer once\n" ); timer_lst.adjust_timer( timer ); } } } else { // others } } if( timeout ) { timer_handler(); timeout = false; } } close( listenfd ); close( pipefd[1] ); close( pipefd[0] ); delete [] users; return 0; }
out
get 5 bytes of client data 222 from 7 adjust timer once timer tick timer tick timer tick close fd 7
