出处:
http://blog.csdn.net/luotuo44/article/details/39670221
本文从简单到复杂,展示如何使用libevent。网上的许多例子都是只有服务器端的,本文里面客户端和服务器端都有,以飨读者。
关于libevent编程时的一些疑问可以阅读《libevent编程疑难解答》。假如读者还想了解libevent的具体实现,可以阅读《libevent源码分析》系统文章。
不说这么多了,直接上代码。
初等:
客户端代码:
-
#include<sys/types.h>
-
#include<sys/socket.h>
-
#include<netinet/in.h>
-
#include<arpa/inet.h>
-
#include<errno.h>
-
#include<unistd.h>
-
-
#include<stdio.h>
-
#include<string.h>
-
#include<stdlib.h>
-
-
#include<event.h>
-
#include<event2/util.h>
-
-
-
-
-
int tcp_connect_server(const char* server_ip, int port);
-
-
-
void cmd_msg_cb(int fd, short events, void* arg);
-
void socket_read_cb(int fd, short events, void *arg);
-
-
int main(int argc, char** argv)
- {
- if( argc < 3 )
- {
- printf("please input 2 parameter\n");
- return -1;
- }
-
-
- //两个参数依次是服务器端的IP地址、端口号
- int sockfd = tcp_connect_server(argv[1], atoi(argv[2]));
- if( sockfd == -1)
- {
- perror("tcp_connect error ");
- return -1;
- }
-
- printf("connect to server successful\n");
-
- struct event_base* base = event_base_new();
-
- struct event *ev_sockfd = event_new(base, sockfd,
- EV_READ | EV_PERSIST,
- socket_read_cb, NULL);
- event_add(ev_sockfd, NULL);
-
- //监听终端输入事件
- struct event* ev_cmd = event_new(base, STDIN_FILENO,
- EV_READ | EV_PERSIST, cmd_msg_cb,
- (void*)&sockfd);
-
-
- event_add(ev_cmd, NULL);
-
- event_base_dispatch(base);
-
- printf("finished \n");
- return 0;
- }
-
-
-
-
-
-
-
void cmd_msg_cb(int fd, short events, void* arg)
- {
- char msg[1024];
-
- int ret = read(fd, msg, sizeof(msg));
- if( ret <= 0 )
- {
- perror("read fail ");
- exit(1);
- }
-
- int sockfd = *((int*)arg);
-
- //把终端的消息发送给服务器端
- //为了简单起见,不考虑写一半数据的情况
- write(sockfd, msg, ret);
- }
-
-
-
void socket_read_cb(int fd, short events, void *arg)
- {
- char msg[1024];
-
- //为了简单起见,不考虑读一半数据的情况
- int len = read(fd, msg, sizeof(msg)-1);
- if( len <= 0 )
- {
- perror("read fail ");
- exit(1);
- }
-
- msg[len] = '\0';
-
- printf("recv %s from server\n", msg);
- }
-
-
-
-
typedef struct sockaddr SA;
-
int tcp_connect_server(const char* server_ip, int port)
- {
- int sockfd, status, save_errno;
- struct sockaddr_in server_addr;
-
- memset(&server_addr, 0, sizeof(server_addr) );
-
- server_addr.sin_family = AF_INET;
- server_addr.sin_port = htons(port);
- status = inet_aton(server_ip, &server_addr.sin_addr);
-
- if( status == 0 ) //the server_ip is not valid value
- {
- errno = EINVAL;
- return -1;
- }
-
- sockfd = ::socket(PF_INET, SOCK_STREAM, 0);
- if( sockfd == -1 )
- return sockfd;
-
-
- status = ::connect(sockfd, (SA*)&server_addr, sizeof(server_addr) );
-
- if( status == -1 )
- {
- save_errno = errno;
- ::close(sockfd);
- errno = save_errno; //the close may be error
- return -1;
- }
-
- evutil_make_socket_nonblocking(sockfd);
-
- return sockfd;
- }
#include<sys/types.h>
#include<sys/socket.h>
#include<netinet/in.h>
#include<arpa/inet.h>
#include<errno.h>
#include<unistd.h>
#include<stdio.h>
#include<string.h>
#include<stdlib.h>
#include<event.h>
#include<event2/util.h>
int tcp_connect_server(const char* server_ip, int port);
void cmd_msg_cb(int fd, short events, void* arg);
void socket_read_cb(int fd, short events, void *arg);
int main(int argc, char** argv)
{
if( argc < 3 )
{
printf("please input 2 parameter\n");
return -1;
}
//两个参数依次是服务器端的IP地址、端口号
int sockfd = tcp_connect_server(argv[1], atoi(argv[2]));
if( sockfd == -1)
{
perror("tcp_connect error ");
return -1;
}
printf("connect to server successful\n");
struct event_base* base = event_base_new();
struct event *ev_sockfd = event_new(base, sockfd,
EV_READ | EV_PERSIST,
socket_read_cb, NULL);
event_add(ev_sockfd, NULL);
//监听终端输入事件
struct event* ev_cmd = event_new(base, STDIN_FILENO,
EV_READ | EV_PERSIST, cmd_msg_cb,
(void*)&sockfd);
event_add(ev_cmd, NULL);
event_base_dispatch(base);
printf("finished \n");
return 0;
}
void cmd_msg_cb(int fd, short events, void* arg)
{
char msg[1024];
int ret = read(fd, msg, sizeof(msg));
if( ret <= 0 )
{
perror("read fail ");
exit(1);
}
int sockfd = *((int*)arg);
//把终端的消息发送给服务器端
//为了简单起见,不考虑写一半数据的情况
write(sockfd, msg, ret);
}
void socket_read_cb(int fd, short events, void *arg)
{
char msg[1024];
//为了简单起见,不考虑读一半数据的情况
int len = read(fd, msg, sizeof(msg)-1);
if( len <= 0 )
{
perror("read fail ");
exit(1);
}
msg[len] = '\0';
printf("recv %s from server\n", msg);
}
typedef struct sockaddr SA;
int tcp_connect_server(const char* server_ip, int port)
{
int sockfd, status, save_errno;
struct sockaddr_in server_addr;
memset(&server_addr, 0, sizeof(server_addr) );
server_addr.sin_family = AF_INET;
server_addr.sin_port = htons(port);
status = inet_aton(server_ip, &server_addr.sin_addr);
if( status == 0 ) //the server_ip is not valid value
{
errno = EINVAL;
return -1;
}
sockfd = ::socket(PF_INET, SOCK_STREAM, 0);
if( sockfd == -1 )
return sockfd;
status = ::connect(sockfd, (SA*)&server_addr, sizeof(server_addr) );
if( status == -1 )
{
save_errno = errno;
::close(sockfd);
errno = save_errno; //the close may be error
return -1;
}
evutil_make_socket_nonblocking(sockfd);
return sockfd;
}
服务器端代码:
-
#include<stdio.h>
-
#include<string.h>
-
#include<errno.h>
-
-
#include<unistd.h>
-
#include<event.h>
-
-
-
-
void accept_cb(int fd, short events, void* arg);
-
void socket_read_cb(int fd, short events, void *arg);
-
-
int tcp_server_init(int port, int listen_num);
-
-
int main(int argc, char** argv)
- {
-
- int listener = tcp_server_init(9999, 10);
- if( listener == -1 )
- {
- perror(" tcp_server_init error ");
- return -1;
- }
-
- struct event_base* base = event_base_new();
-
- //添加监听客户端请求连接事件
- struct event* ev_listen = event_new(base, listener, EV_READ | EV_PERSIST,
- accept_cb, base);
- event_add(ev_listen, NULL);
-
-
- event_base_dispatch(base);
-
- return 0;
- }
-
-
-
-
void accept_cb(int fd, short events, void* arg)
- {
- evutil_socket_t sockfd;
-
- struct sockaddr_in client;
- socklen_t len = sizeof(client);
-
- sockfd = ::accept(fd, (struct sockaddr*)&client, &len );
- evutil_make_socket_nonblocking(sockfd);
-
- printf("accept a client %d\n", sockfd);
-
- struct event_base* base = (event_base*)arg;
-
- //仅仅是为了动态创建一个event结构体
- struct event *ev = event_new(NULL, -1, 0, NULL, NULL);
- //将动态创建的结构体作为event的回调参数
- event_assign(ev, base, sockfd, EV_READ | EV_PERSIST,
- socket_read_cb, (void*)ev);
-
- event_add(ev, NULL);
- }
-
-
-
void socket_read_cb(int fd, short events, void *arg)
- {
- char msg[4096];
- struct event *ev = (struct event*)arg;
- int len = read(fd, msg, sizeof(msg) - 1);
-
-
-
- if( len <= 0 )
- {
- printf("some error happen when read\n");
- event_free(ev);
- close(fd);
- return ;
- }
-
- msg[len] = '\0';
- printf("recv the client msg: %s", msg);
-
- char reply_msg[4096] = "I have recvieced the msg: ";
- strcat(reply_msg + strlen(reply_msg), msg);
-
- write(fd, reply_msg, strlen(reply_msg) );
- }
-
-
-
-
typedef struct sockaddr SA;
-
int tcp_server_init(int port, int listen_num)
- {
- int errno_save;
- evutil_socket_t listener;
-
- listener = ::socket(AF_INET, SOCK_STREAM, 0);
- if( listener == -1 )
- return -1;
-
- //允许多次绑定同一个地址。要用在socket和bind之间
- evutil_make_listen_socket_reuseable(listener);
-
- struct sockaddr_in sin;
- sin.sin_family = AF_INET;
- sin.sin_addr.s_addr = 0;
- sin.sin_port = htons(port);
-
- if( ::bind(listener, (SA*)&sin, sizeof(sin)) < 0 )
- goto error;
-
- if( ::listen(listener, listen_num) < 0)
- goto error;
-
-
- //跨平台统一接口,将套接字设置为非阻塞状态
- evutil_make_socket_nonblocking(listener);
-
- return listener;
-
- error:
- errno_save = errno;
- evutil_closesocket(listener);
- errno = errno_save;
-
- return -1;
- }
#include<stdio.h>
#include<string.h>
#include<errno.h>
#include<unistd.h>
#include<event.h>
void accept_cb(int fd, short events, void* arg);
void socket_read_cb(int fd, short events, void *arg);
int tcp_server_init(int port, int listen_num);
int main(int argc, char** argv)
{
int listener = tcp_server_init(9999, 10);
if( listener == -1 )
{
perror(" tcp_server_init error ");
return -1;
}
struct event_base* base = event_base_new();
//添加监听客户端请求连接事件
struct event* ev_listen = event_new(base, listener, EV_READ | EV_PERSIST,
accept_cb, base);
event_add(ev_listen, NULL);
event_base_dispatch(base);
return 0;
}
void accept_cb(int fd, short events, void* arg)
{
evutil_socket_t sockfd;
struct sockaddr_in client;
socklen_t len = sizeof(client);
sockfd = ::accept(fd, (struct sockaddr*)&client, &len );
evutil_make_socket_nonblocking(sockfd);
printf("accept a client %d\n", sockfd);
struct event_base* base = (event_base*)arg;
//仅仅是为了动态创建一个event结构体
struct event *ev = event_new(NULL, -1, 0, NULL, NULL);
//将动态创建的结构体作为event的回调参数
event_assign(ev, base, sockfd, EV_READ | EV_PERSIST,
socket_read_cb, (void*)ev);
event_add(ev, NULL);
}
void socket_read_cb(int fd, short events, void *arg)
{
char msg[4096];
struct event *ev = (struct event*)arg;
int len = read(fd, msg, sizeof(msg) - 1);
if( len <= 0 )
{
printf("some error happen when read\n");
event_free(ev);
close(fd);
return ;
}
msg[len] = '\0';
printf("recv the client msg: %s", msg);
char reply_msg[4096] = "I have recvieced the msg: ";
strcat(reply_msg + strlen(reply_msg), msg);
write(fd, reply_msg, strlen(reply_msg) );
}
typedef struct sockaddr SA;
int tcp_server_init(int port, int listen_num)
{
int errno_save;
evutil_socket_t listener;
listener = ::socket(AF_INET, SOCK_STREAM, 0);
if( listener == -1 )
return -1;
//允许多次绑定同一个地址。要用在socket和bind之间
evutil_make_listen_socket_reuseable(listener);
struct sockaddr_in sin;
sin.sin_family = AF_INET;
sin.sin_addr.s_addr = 0;
sin.sin_port = htons(port);
if( ::bind(listener, (SA*)&sin, sizeof(sin)) < 0 )
goto error;
if( ::listen(listener, listen_num) < 0)
goto error;
//跨平台统一接口,将套接字设置为非阻塞状态
evutil_make_socket_nonblocking(listener);
return listener;
error:
errno_save = errno;
evutil_closesocket(listener);
errno = errno_save;
return -1;
}
中等:
客户端代码:
-
#include<sys/types.h>
-
#include<sys/socket.h>
-
#include<netinet/in.h>
-
#include<arpa/inet.h>
-
#include<errno.h>
-
#include<unistd.h>
-
-
#include<stdio.h>
-
#include<string.h>
-
#include<stdlib.h>
-
-
#include<event.h>
-
#include<event2/bufferevent.h>
-
#include<event2/buffer.h>
-
#include<event2/util.h>
-
-
-
-
-
int tcp_connect_server(const char* server_ip, int port);
-
-
-
void cmd_msg_cb(int fd, short events, void* arg);
-
void server_msg_cb(struct bufferevent* bev, void* arg);
-
void event_cb(struct bufferevent *bev, short event, void *arg);
-
-
int main(int argc, char** argv)
- {
- if( argc < 3 )
- {
- printf("please input 2 parameter\n");
- return -1;
- }
-
-
- //两个参数依次是服务器端的IP地址、端口号
- int sockfd = tcp_connect_server(argv[1], atoi(argv[2]));
- if( sockfd == -1)
- {
- perror("tcp_connect error ");
- return -1;
- }
-
- printf("connect to server successful\n");
-
- struct event_base* base = event_base_new();
-
- struct bufferevent* bev = bufferevent_socket_new(base, sockfd,
- BEV_OPT_CLOSE_ON_FREE);
-
- //监听终端输入事件
- struct event* ev_cmd = event_new(base, STDIN_FILENO,
- EV_READ | EV_PERSIST, cmd_msg_cb,
- (void*)bev);
- event_add(ev_cmd, NULL);
-
- //当socket关闭时会用到回调参数
- bufferevent_setcb(bev, server_msg_cb, NULL, event_cb, (void*)ev_cmd);
- bufferevent_enable(bev, EV_READ | EV_PERSIST);
-
-
- event_base_dispatch(base);
-
- printf("finished \n");
- return 0;
- }
-
-
-
-
-
-
-
void cmd_msg_cb(int fd, short events, void* arg)
- {
- char msg[1024];
-
- int ret = read(fd, msg, sizeof(msg));
- if( ret < 0 )
- {
- perror("read fail ");
- exit(1);
- }
-
- struct bufferevent* bev = (struct bufferevent*)arg;
-
- //把终端的消息发送给服务器端
- bufferevent_write(bev, msg, ret);
- }
-
-
-
void server_msg_cb(struct bufferevent* bev, void* arg)
- {
- char msg[1024];
-
- size_t len = bufferevent_read(bev, msg, sizeof(msg));
- msg[len] = '\0';
-
- printf("recv %s from server\n", msg);
- }
-
-
-
void event_cb(struct bufferevent *bev, short event, void *arg)
- {
-
- if (event & BEV_EVENT_EOF)
- printf("connection closed\n");
- else if (event & BEV_EVENT_ERROR)
- printf("some other error\n");
-
- //这将自动close套接字和free读写缓冲区
- bufferevent_free(bev);
-
- struct event *ev = (struct event*)arg;
- //因为socket已经没有,所以这个event也没有存在的必要了
- event_free(ev);
- }
-
-
-
typedef struct sockaddr SA;
-
int tcp_connect_server(const char* server_ip, int port)
- {
- int sockfd, status, save_errno;
- struct sockaddr_in server_addr;
-
- memset(&server_addr, 0, sizeof(server_addr) );
-
- server_addr.sin_family = AF_INET;
- server_addr.sin_port = htons(port);
- status = inet_aton(server_ip, &server_addr.sin_addr);
-
- if( status == 0 ) //the server_ip is not valid value
- {
- errno = EINVAL;
- return -1;
- }
-
- sockfd = ::socket(PF_INET, SOCK_STREAM, 0);
- if( sockfd == -1 )
- return sockfd;
-
-
- status = ::connect(sockfd, (SA*)&server_addr, sizeof(server_addr) );
-
- if( status == -1 )
- {
- save_errno = errno;
- ::close(sockfd);
- errno = save_errno; //the close may be error
- return -1;
- }
-
- evutil_make_socket_nonblocking(sockfd);
-
- return sockfd;
- }
#include<sys/types.h>
#include<sys/socket.h>
#include<netinet/in.h>
#include<arpa/inet.h>
#include<errno.h>
#include<unistd.h>
#include<stdio.h>
#include<string.h>
#include<stdlib.h>
#include<event.h>
#include<event2/bufferevent.h>
#include<event2/buffer.h>
#include<event2/util.h>
int tcp_connect_server(const char* server_ip, int port);
void cmd_msg_cb(int fd, short events, void* arg);
void server_msg_cb(struct bufferevent* bev, void* arg);
void event_cb(struct bufferevent *bev, short event, void *arg);
int main(int argc, char** argv)
{
if( argc < 3 )
{
printf("please input 2 parameter\n");
return -1;
}
//两个参数依次是服务器端的IP地址、端口号
int sockfd = tcp_connect_server(argv[1], atoi(argv[2]));
if( sockfd == -1)
{
perror("tcp_connect error ");
return -1;
}
printf("connect to server successful\n");
struct event_base* base = event_base_new();
struct bufferevent* bev = bufferevent_socket_new(base, sockfd,
BEV_OPT_CLOSE_ON_FREE);
//监听终端输入事件
struct event* ev_cmd = event_new(base, STDIN_FILENO,
EV_READ | EV_PERSIST, cmd_msg_cb,
(void*)bev);
event_add(ev_cmd, NULL);
//当socket关闭时会用到回调参数
bufferevent_setcb(bev, server_msg_cb, NULL, event_cb, (void*)ev_cmd);
bufferevent_enable(bev, EV_READ | EV_PERSIST);
event_base_dispatch(base);
printf("finished \n");
return 0;
}
void cmd_msg_cb(int fd, short events, void* arg)
{
char msg[1024];
int ret = read(fd, msg, sizeof(msg));
if( ret < 0 )
{
perror("read fail ");
exit(1);
}
struct bufferevent* bev = (struct bufferevent*)arg;
//把终端的消息发送给服务器端
bufferevent_write(bev, msg, ret);
}
void server_msg_cb(struct bufferevent* bev, void* arg)
{
char msg[1024];
size_t len = bufferevent_read(bev, msg, sizeof(msg));
msg[len] = '\0';
printf("recv %s from server\n", msg);
}
void event_cb(struct bufferevent *bev, short event, void *arg)
{
if (event & BEV_EVENT_EOF)
printf("connection closed\n");
else if (event & BEV_EVENT_ERROR)
printf("some other error\n");
//这将自动close套接字和free读写缓冲区
bufferevent_free(bev);
struct event *ev = (struct event*)arg;
//因为socket已经没有,所以这个event也没有存在的必要了
event_free(ev);
}
typedef struct sockaddr SA;
int tcp_connect_server(const char* server_ip, int port)
{
int sockfd, status, save_errno;
struct sockaddr_in server_addr;
memset(&server_addr, 0, sizeof(server_addr) );
server_addr.sin_family = AF_INET;
server_addr.sin_port = htons(port);
status = inet_aton(server_ip, &server_addr.sin_addr);
if( status == 0 ) //the server_ip is not valid value
{
errno = EINVAL;
return -1;
}
sockfd = ::socket(PF_INET, SOCK_STREAM, 0);
if( sockfd == -1 )
return sockfd;
status = ::connect(sockfd, (SA*)&server_addr, sizeof(server_addr) );
if( status == -1 )
{
save_errno = errno;
::close(sockfd);
errno = save_errno; //the close may be error
return -1;
}
evutil_make_socket_nonblocking(sockfd);
return sockfd;
}
服务器端代码:
-
#include<stdio.h>
-
#include<string.h>
-
#include<errno.h>
-
-
#include<event.h>
-
#include<event2/bufferevent.h>
-
-
-
-
void accept_cb(int fd, short events, void* arg);
-
void socket_read_cb(bufferevent* bev, void* arg);
-
void event_cb(struct bufferevent *bev, short event, void *arg);
-
int tcp_server_init(int port, int listen_num);
-
-
int main(int argc, char** argv)
- {
-
- int listener = tcp_server_init(9999, 10);
- if( listener == -1 )
- {
- perror(" tcp_server_init error ");
- return -1;
- }
-
- struct event_base* base = event_base_new();
-
- //添加监听客户端请求连接事件
- struct event* ev_listen = event_new(base, listener, EV_READ | EV_PERSIST,
- accept_cb, base);
- event_add(ev_listen, NULL);
-
-
- event_base_dispatch(base);
- event_base_free(base);
-
-
- return 0;
- }
-
-
-
-
void accept_cb(int fd, short events, void* arg)
- {
- evutil_socket_t sockfd;
-
- struct sockaddr_in client;
- socklen_t len = sizeof(client);
-
- sockfd = ::accept(fd, (struct sockaddr*)&client, &len );
- evutil_make_socket_nonblocking(sockfd);
-
- printf("accept a client %d\n", sockfd);
-
- struct event_base* base = (event_base*)arg;
-
- bufferevent* bev = bufferevent_socket_new(base, sockfd, BEV_OPT_CLOSE_ON_FREE);
- bufferevent_setcb(bev, socket_read_cb, NULL, event_cb, arg);
-
- bufferevent_enable(bev, EV_READ | EV_PERSIST);
- }
-
-
-
-
void socket_read_cb(bufferevent* bev, void* arg)
- {
- char msg[4096];
-
- size_t len = bufferevent_read(bev, msg, sizeof(msg));
-
- msg[len] = '\0';
- printf("recv the client msg: %s", msg);
-
-
- char reply_msg[4096] = "I have recvieced the msg: ";
-
- strcat(reply_msg + strlen(reply_msg), msg);
- bufferevent_write(bev, reply_msg, strlen(reply_msg));
- }
-
-
-
-
void event_cb(struct bufferevent *bev, short event, void *arg)
- {
-
- if (event & BEV_EVENT_EOF)
- printf("connection closed\n");
- else if (event & BEV_EVENT_ERROR)
- printf("some other error\n");
-
- //这将自动close套接字和free读写缓冲区
- bufferevent_free(bev);
- }
-
-
-
typedef struct sockaddr SA;
-
int tcp_server_init(int port, int listen_num)
- {
- int errno_save;
- evutil_socket_t listener;
-
- listener = ::socket(AF_INET, SOCK_STREAM, 0);
- if( listener == -1 )
- return -1;
-
- //允许多次绑定同一个地址。要用在socket和bind之间
- evutil_make_listen_socket_reuseable(listener);
-
- struct sockaddr_in sin;
- sin.sin_family = AF_INET;
- sin.sin_addr.s_addr = 0;
- sin.sin_port = htons(port);
-
- if( ::bind(listener, (SA*)&sin, sizeof(sin)) < 0 )
- goto error;
-
- if( ::listen(listener, listen_num) < 0)
- goto error;
-
-
- //跨平台统一接口,将套接字设置为非阻塞状态
- evutil_make_socket_nonblocking(listener);
-
- return listener;
-
- error:
- errno_save = errno;
- evutil_closesocket(listener);
- errno = errno_save;
-
- return -1;
- }
#include<stdio.h>
#include<string.h>
#include<errno.h>
#include<event.h>
#include<event2/bufferevent.h>
void accept_cb(int fd, short events, void* arg);
void socket_read_cb(bufferevent* bev, void* arg);
void event_cb(struct bufferevent *bev, short event, void *arg);
int tcp_server_init(int port, int listen_num);
int main(int argc, char** argv)
{
int listener = tcp_server_init(9999, 10);
if( listener == -1 )
{
perror(" tcp_server_init error ");
return -1;
}
struct event_base* base = event_base_new();
//添加监听客户端请求连接事件
struct event* ev_listen = event_new(base, listener, EV_READ | EV_PERSIST,
accept_cb, base);
event_add(ev_listen, NULL);
event_base_dispatch(base);
event_base_free(base);
return 0;
}
void accept_cb(int fd, short events, void* arg)
{
evutil_socket_t sockfd;
struct sockaddr_in client;
socklen_t len = sizeof(client);
sockfd = ::accept(fd, (struct sockaddr*)&client, &len );
evutil_make_socket_nonblocking(sockfd);
printf("accept a client %d\n", sockfd);
struct event_base* base = (event_base*)arg;
bufferevent* bev = bufferevent_socket_new(base, sockfd, BEV_OPT_CLOSE_ON_FREE);
bufferevent_setcb(bev, socket_read_cb, NULL, event_cb, arg);
bufferevent_enable(bev, EV_READ | EV_PERSIST);
}
void socket_read_cb(bufferevent* bev, void* arg)
{
char msg[4096];
size_t len = bufferevent_read(bev, msg, sizeof(msg));
msg[len] = '\0';
printf("recv the client msg: %s", msg);
char reply_msg[4096] = "I have recvieced the msg: ";
strcat(reply_msg + strlen(reply_msg), msg);
bufferevent_write(bev, reply_msg, strlen(reply_msg));
}
void event_cb(struct bufferevent *bev, short event, void *arg)
{
if (event & BEV_EVENT_EOF)
printf("connection closed\n");
else if (event & BEV_EVENT_ERROR)
printf("some other error\n");
//这将自动close套接字和free读写缓冲区
bufferevent_free(bev);
}
typedef struct sockaddr SA;
int tcp_server_init(int port, int listen_num)
{
int errno_save;
evutil_socket_t listener;
listener = ::socket(AF_INET, SOCK_STREAM, 0);
if( listener == -1 )
return -1;
//允许多次绑定同一个地址。要用在socket和bind之间
evutil_make_listen_socket_reuseable(listener);
struct sockaddr_in sin;
sin.sin_family = AF_INET;
sin.sin_addr.s_addr = 0;
sin.sin_port = htons(port);
if( ::bind(listener, (SA*)&sin, sizeof(sin)) < 0 )
goto error;
if( ::listen(listener, listen_num) < 0)
goto error;
//跨平台统一接口,将套接字设置为非阻塞状态
evutil_make_socket_nonblocking(listener);
return listener;
error:
errno_save = errno;
evutil_closesocket(listener);
errno = errno_save;
return -1;
}
高等:
客户端代码:
-
#include<sys/types.h>
-
#include<sys/socket.h>
-
#include<netinet/in.h>
-
#include<arpa/inet.h>
-
#include<errno.h>
-
#include<unistd.h>
-
-
#include<stdio.h>
-
#include<string.h>
-
#include<stdlib.h>
-
-
#include<event.h>
-
#include<event2/bufferevent.h>
-
#include<event2/buffer.h>
-
#include<event2/util.h>
-
-
-
-
-
int tcp_connect_server(const char* server_ip, int port);
-
-
-
void cmd_msg_cb(int fd, short events, void* arg);
-
void server_msg_cb(struct bufferevent* bev, void* arg);
-
void event_cb(struct bufferevent *bev, short event, void *arg);
-
-
int main(int argc, char** argv)
- {
- if( argc < 3 )
- {
- //两个参数依次是服务器端的IP地址、端口号
- printf("please input 2 parameter\n");
- return -1;
- }
-
- struct event_base *base = event_base_new();
-
- struct bufferevent* bev = bufferevent_socket_new(base, -1,
- BEV_OPT_CLOSE_ON_FREE);
-
- //监听终端输入事件
- struct event* ev_cmd = event_new(base, STDIN_FILENO,
- EV_READ | EV_PERSIST,
- cmd_msg_cb, (void*)bev);
-
-
- event_add(ev_cmd, NULL);
-
- struct sockaddr_in server_addr;
-
- memset(&server_addr, 0, sizeof(server_addr) );
-
- server_addr.sin_family = AF_INET;
- server_addr.sin_port = htons(atoi(argv[2]));
- inet_aton(argv[1], &server_addr.sin_addr);
-
- bufferevent_socket_connect(bev, (struct sockaddr *)&server_addr,
- sizeof(server_addr));
-
-
- bufferevent_setcb(bev, server_msg_cb, NULL, event_cb, (void*)ev_cmd);
- bufferevent_enable(bev, EV_READ | EV_PERSIST);
-
-
-
- event_base_dispatch(base);
-
- printf("finished \n");
- return 0;
- }
-
-
-
-
-
-
void cmd_msg_cb(int fd, short events, void* arg)
- {
- char msg[1024];
-
- int ret = read(fd, msg, sizeof(msg));
- if( ret < 0 )
- {
- perror("read fail ");
- exit(1);
- }
-
- struct bufferevent* bev = (struct bufferevent*)arg;
-
- //把终端的消息发送给服务器端
- bufferevent_write(bev, msg, ret);
- }
-
-
-
void server_msg_cb(struct bufferevent* bev, void* arg)
- {
- char msg[1024];
-
- size_t len = bufferevent_read(bev, msg, sizeof(msg));
- msg[len] = '\0';
-
- printf("recv %s from server\n", msg);
- }
-
-
-
void event_cb(struct bufferevent *bev, short event, void *arg)
- {
-
- if (event & BEV_EVENT_EOF)
- printf("connection closed\n");
- else if (event & BEV_EVENT_ERROR)
- printf("some other error\n");
- else if( event & BEV_EVENT_CONNECTED)
- {
- printf("the client has connected to server\n");
- return ;
- }
-
- //这将自动close套接字和free读写缓冲区
- bufferevent_free(bev);
-
- struct event *ev = (struct event*)arg;
- event_free(ev);
- }
#include<sys/types.h>
#include<sys/socket.h>
#include<netinet/in.h>
#include<arpa/inet.h>
#include<errno.h>
#include<unistd.h>
#include<stdio.h>
#include<string.h>
#include<stdlib.h>
#include<event.h>
#include<event2/bufferevent.h>
#include<event2/buffer.h>
#include<event2/util.h>
int tcp_connect_server(const char* server_ip, int port);
void cmd_msg_cb(int fd, short events, void* arg);
void server_msg_cb(struct bufferevent* bev, void* arg);
void event_cb(struct bufferevent *bev, short event, void *arg);
int main(int argc, char** argv)
{
if( argc < 3 )
{
//两个参数依次是服务器端的IP地址、端口号
printf("please input 2 parameter\n");
return -1;
}
struct event_base *base = event_base_new();
struct bufferevent* bev = bufferevent_socket_new(base, -1,
BEV_OPT_CLOSE_ON_FREE);
//监听终端输入事件
struct event* ev_cmd = event_new(base, STDIN_FILENO,
EV_READ | EV_PERSIST,
cmd_msg_cb, (void*)bev);
event_add(ev_cmd, NULL);
struct sockaddr_in server_addr;
memset(&server_addr, 0, sizeof(server_addr) );
server_addr.sin_family = AF_INET;
server_addr.sin_port = htons(atoi(argv[2]));
inet_aton(argv[1], &server_addr.sin_addr);
bufferevent_socket_connect(bev, (struct sockaddr *)&server_addr,
sizeof(server_addr));
bufferevent_setcb(bev, server_msg_cb, NULL, event_cb, (void*)ev_cmd);
bufferevent_enable(bev, EV_READ | EV_PERSIST);
event_base_dispatch(base);
printf("finished \n");
return 0;
}
void cmd_msg_cb(int fd, short events, void* arg)
{
char msg[1024];
int ret = read(fd, msg, sizeof(msg));
if( ret < 0 )
{
perror("read fail ");
exit(1);
}
struct bufferevent* bev = (struct bufferevent*)arg;
//把终端的消息发送给服务器端
bufferevent_write(bev, msg, ret);
}
void server_msg_cb(struct bufferevent* bev, void* arg)
{
char msg[1024];
size_t len = bufferevent_read(bev, msg, sizeof(msg));
msg[len] = '\0';
printf("recv %s from server\n", msg);
}
void event_cb(struct bufferevent *bev, short event, void *arg)
{
if (event & BEV_EVENT_EOF)
printf("connection closed\n");
else if (event & BEV_EVENT_ERROR)
printf("some other error\n");
else if( event & BEV_EVENT_CONNECTED)
{
printf("the client has connected to server\n");
return ;
}
//这将自动close套接字和free读写缓冲区
bufferevent_free(bev);
struct event *ev = (struct event*)arg;
event_free(ev);
}
服务器端代码:
-
#include<netinet/in.h>
-
#include<sys/socket.h>
-
#include<unistd.h>
-
-
#include<stdio.h>
-
#include<string.h>
-
-
#include<event.h>
-
#include<listener.h>
-
#include<bufferevent.h>
-
#include<thread.h>
-
-
-
void listener_cb(evconnlistener *listener, evutil_socket_t fd,
- struct sockaddr *sock, int socklen, void *arg);
-
-
void socket_read_cb(bufferevent *bev, void *arg);
-
void socket_event_cb(bufferevent *bev, short events, void *arg);
-
-
int main()
- {
- //evthread_use_pthreads();//enable threads
-
- struct sockaddr_in sin;
- memset(&sin, 0, sizeof(struct sockaddr_in));
- sin.sin_family = AF_INET;
- sin.sin_port = htons(9999);
-
- event_base *base = event_base_new();
- evconnlistener *listener
- = evconnlistener_new_bind(base, listener_cb, base,
- LEV_OPT_REUSEABLE|LEV_OPT_CLOSE_ON_FREE,
- 10, (struct sockaddr*)&sin,
- sizeof(struct sockaddr_in));
-
- event_base_dispatch(base);
-
- evconnlistener_free(listener);
- event_base_free(base);
-
- return 0;
- }
-
-
-
//一个新客户端连接上服务器了
-
//当此函数被调用时,libevent已经帮我们accept了这个客户端。该客户端的
-
//文件描述符为fd
-
void listener_cb(evconnlistener *listener, evutil_socket_t fd,
- struct sockaddr *sock, int socklen, void *arg)
- {
- printf("accept a client %d\n", fd);
-
- event_base *base = (event_base*)arg;
-
- //为这个客户端分配一个bufferevent
- bufferevent *bev = bufferevent_socket_new(base, fd,
- BEV_OPT_CLOSE_ON_FREE);
-
- bufferevent_setcb(bev, socket_read_cb, NULL, socket_event_cb, NULL);
- bufferevent_enable(bev, EV_READ | EV_PERSIST);
- }
-
-
-
void socket_read_cb(bufferevent *bev, void *arg)
- {
- char msg[4096];
-
- size_t len = bufferevent_read(bev, msg, sizeof(msg)-1 );
-
- msg[len] = '\0';
- printf("server read the data %s\n", msg);
-
- char reply[] = "I has read your data";
- bufferevent_write(bev, reply, strlen(reply) );
- }
-
-
-
void socket_event_cb(bufferevent *bev, short events, void *arg)
- {
- if (events & BEV_EVENT_EOF)
- printf("connection closed\n");
- else if (events & BEV_EVENT_ERROR)
- printf("some other error\n");
-
- //这将自动close套接字和free读写缓冲区
- bufferevent_free(bev);
- }
#include<netinet/in.h>
#include<sys/socket.h>
#include<unistd.h>
#include<stdio.h>
#include<string.h>
#include<event.h>
#include<listener.h>
#include<bufferevent.h>
#include<thread.h>
void listener_cb(evconnlistener *listener, evutil_socket_t fd,
struct sockaddr *sock, int socklen, void *arg);
void socket_read_cb(bufferevent *bev, void *arg);
void socket_event_cb(bufferevent *bev, short events, void *arg);
int main()
{
//evthread_use_pthreads();//enable threads
struct sockaddr_in sin;
memset(&sin, 0, sizeof(struct sockaddr_in));
sin.sin_family = AF_INET;
sin.sin_port = htons(9999);
event_base *base = event_base_new();
evconnlistener *listener
= evconnlistener_new_bind(base, listener_cb, base,
LEV_OPT_REUSEABLE|LEV_OPT_CLOSE_ON_FREE,
10, (struct sockaddr*)&sin,
sizeof(struct sockaddr_in));
event_base_dispatch(base);
evconnlistener_free(listener);
event_base_free(base);
return 0;
}
//一个新客户端连接上服务器了
//当此函数被调用时,libevent已经帮我们accept了这个客户端。该客户端的
//文件描述符为fd
void listener_cb(evconnlistener *listener, evutil_socket_t fd,
struct sockaddr *sock, int socklen, void *arg)
{
printf("accept a client %d\n", fd);
event_base *base = (event_base*)arg;
//为这个客户端分配一个bufferevent
bufferevent *bev = bufferevent_socket_new(base, fd,
BEV_OPT_CLOSE_ON_FREE);
bufferevent_setcb(bev, socket_read_cb, NULL, socket_event_cb, NULL);
bufferevent_enable(bev, EV_READ | EV_PERSIST);
}
void socket_read_cb(bufferevent *bev, void *arg)
{
char msg[4096];
size_t len = bufferevent_read(bev, msg, sizeof(msg)-1 );
msg[len] = '\0';
printf("server read the data %s\n", msg);
char reply[] = "I has read your data";
bufferevent_write(bev, reply, strlen(reply) );
}
void socket_event_cb(bufferevent *bev, short events, void *arg)
{
if (events & BEV_EVENT_EOF)
printf("connection closed\n");
else if (events & BEV_EVENT_ERROR)
printf("some other error\n");
//这将自动close套接字和free读写缓冲区
bufferevent_free(bev);
}