ENet的目的是提供一个相对轻量、简单、稳定的基于UDP的网络通信。
主要特色就是提供了可选的、可靠的、顺序传送的数据包。
准备
下载：http://enet.bespin.org/Downloads.html
编译安装
./configure --prefix=/usr/local/enet
make
make install
示例代码
enet_server.cpp
代码：
#include <iostream>
#include <enet/enet.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
using namespace std;
void run()
{
ENetAddress address;
ENetHost * server;
/* Bind the server to the default localhost. */
/* A specific host address can be specified by */
/* enet_address_set_host (& address, "x.x.x.x"); */
address.host = ENET_HOST_ANY;
/* Bind the server to port 1234. */
address.port = 12345;
server = enet_host_create (& address /* the address to bind the server host to */,
32 /* allow up to 32 clients and/or outgoing connections */,
2 /* allow up to 2 channels to be used, 0 and 1 */,
0 /* assume any amount of incoming bandwidth */,
0 /* assume any amount of outgoing bandwidth */);
if (server == NULL)
{
fprintf (stderr,
"An error occurred while trying to create an ENet server host.
");
exit (EXIT_FAILURE);
}
ENetEvent event;
/* Wait up to 1000 milliseconds for an event. */
while (enet_host_service (server, & event, 1000) >= 0)
{
switch (event.type)
{
case ENET_EVENT_TYPE_CONNECT:
printf ("A new client connected from %x:%u.
",
event.peer -> address.host,
event.peer -> address.port);
/* Store any relevant client information here. */
//event.peer -> data = "Client information";
event.peer -> data = new char[10];
strcpy ((char*)(event.peer -> data), "foo1");
break;
case ENET_EVENT_TYPE_RECEIVE:
printf ("From %s,%u[len=%u]: %s
",
event.peer -> data,
event.channelID,
event.packet -> dataLength,
event.packet -> data);
/* Clean up the packet now that we're done using it. */
enet_peer_send (event.peer, 0, event.packet);
/* One could just use enet_host_service() instead. */
enet_host_flush (server);
enet_packet_destroy (event.packet);
break;
case ENET_EVENT_TYPE_DISCONNECT:
printf ("%s disconnected.
", event.peer -> data);
/* Reset the peer's client information. */
event.peer -> data = NULL;
}
}
}
int main()
{
if (enet_initialize () != 0)
{
fprintf (stderr, "An error occurred while initializing ENet.
");
return EXIT_FAILURE;
}
run();
return 0;
}
编译：
g++ -g e_server.cpp -o e_server -I /usr/local/enet/include/ /usr/local/enet/lib/libenet.a
enet_client
代码：
#include <iostream>
#include <enet/enet.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
using namespace std;
void run()
{
ENetHost * client;
client = enet_host_create (NULL /* create a client host */,
1 /* only allow 1 outgoing connection */,
2 /* allow up 2 channels to be used, 0 and 1 */,
0 /* assume any amount of incoming bandwidth */,
0 /* assume any amount of outgoing bandwidth */);
if (client == NULL)
{
fprintf (stderr,
"An error occurred while trying to create an ENet client host.
");
exit (EXIT_FAILURE);
}
ENetAddress address;
ENetEvent event;
ENetPeer *peer;
/* Connect to some.server.net:1234. */
enet_address_set_host (& address, "192.168.0.123");
address.port = 12345;
/* Initiate the connection, allocating the two channels 0 and 1. */
peer = enet_host_connect (client, & address, 2, 0);
if (peer == NULL)
{
fprintf (stderr,
"No available peers for initiating an ENet connection.
");
return ;
}
ENetPacket * packet = enet_packet_create ("packet",
strlen ("packet") + 1,
ENET_PACKET_FLAG_RELIABLE);
/* Extend the packet so and append the string "foo", so it now */
/* contains "packetfoo " */
enet_packet_resize (packet, strlen ("packetfoo") + 1);
strcpy ((char*)(& packet -> data [strlen ("packet")]), "foo");
/* Wait up to 5 seconds for the connection attempt to succeed. */
if (enet_host_service (client, & event, 5000) > 0 &&
event.type == ENET_EVENT_TYPE_CONNECT)
{
printf ("Connection to some.server.net:1234 succeeded.");
/* Create a reliable packet of size 7 containing "packet " */
/* Send the packet to the peer over channel id 0. */
/* One could also broadcast the packet by */
/* enet_host_broadcast (host, 0, packet); */
enet_peer_send (peer, 0, packet);
/* One could just use enet_host_service() instead. */
enet_host_flush (client);
event.peer -> data = new char[10];
strcpy ((char*)(event.peer -> data), "foo2");
}
else
{
enet_peer_reset (peer);
printf ("Connection to some.server.net:1234 failed.");
return ;
}
char msg[200] = {0};
/* Wait up to 5 seconds for the connection attempt to succeed. */
while (enet_host_service (client, & event, 5000) >= 0)
{
switch (event.type)
{
case ENET_EVENT_TYPE_RECEIVE:
printf ("From %s,%u[len=%u]: %s
",
event.peer -> data,
event.channelID,
event.packet -> dataLength,
event.packet -> data);
/* Clean up the packet now that we're done using it. */
//enet_packet_destroy (event.packet);
break;
case ENET_EVENT_TYPE_DISCONNECT:
printf ("%s disconnected.
", event.peer -> data);
/* Reset the peer's client information. */
event.peer -> data = NULL;
}
/*************
// enet应该放在单独的线程里跑,scanf阻塞后会,影响enet_host_service发送心跳
// 心跳1s一次,如果5s内没有心跳,服务端会提示连接断开
scanf("%s",msg);
enet_packet_resize (packet, strlen (msg) + 1);
strcpy ((char*)( packet -> data ), msg);
enet_peer_send (peer, 0, packet);
enet_host_flush (client);*/
}
}
int main()
{
if (enet_initialize () != 0)
{
fprintf (stderr, "An error occurred while initializing ENet.
");
return EXIT_FAILURE;
}
run();
return 0;
}
编译：
g++ -g e_client.cpp -o e_client -I /usr/local/enet/include/ /usr/local/enet/lib/libenet.a
执行结果
自己把IP“192.168.0.123”改一下,编译之后直接运行即可。
服务端：
$ ./e_server
A new client connected from 870fa8c0:41543.
From foo1,0[len=10]: packetfoo
From foo1,0[len=4]: ads
From foo1,0[len=6]: fadsf
客户端：
$ ./e_client
Connection to some.server.net:1234 succeeded.From foo2,0[len=10]: packetfoo
1
From foo2,0[len=2]: 1
1
From foo2,0[len=2]: 1