Library like ENet, but for TCP?
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by
Milo
on Game Development
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or by Milo
Published on 2012-05-09T01:55:31Z
Indexed on
2012/06/08
4:47 UTC
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Hit count: 437
c++
|networking
I'm not looking to use boost::asio, it is overly complex for my needs.
I'm building a game that is cross platform, for desktop, iPhone and Android.
I found a library called ENet which is pretty much what I need, but it uses UDP which does not seem to support encryption and a few other things. Given that the game is an event driven card game, TCP seems like the right fit.
However, all I have found is WINSOCK / berkley sockets and bost::asio.
Here is a sample client server application with ENet:
#include <enet/enet.h>
#include <stdlib.h>
#include <string>
#include <iostream>
class Host
{
ENetAddress address;
ENetHost * server;
ENetHost* client;
ENetEvent event;
public:
Host()
:server(NULL)
{
enet_initialize();
setupServer();
}
void setupServer()
{
if(server)
{
enet_host_destroy(server);
server = NULL;
}
address.host = ENET_HOST_ANY;
/* Bind the server to port 1234. */
address.port = 1721;
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 */);
}
void daLoop()
{
while(true)
{
/* Wait up to 1000 milliseconds for an event. */
while (enet_host_service (server, & event, 5000) > 0)
{
ENetPacket * packet;
switch (event.type)
{
case ENET_EVENT_TYPE_CONNECT:
printf ("A new client connected from %x:%u.\n",
event.peer -> address.host,
event.peer -> address.port);
/* Store any relevant client information here. */
event.peer -> data = "Client information";
/* Create a reliable packet of size 7 containing "packet\0" */
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\0" */
enet_packet_resize (packet, strlen ("packetfoo") + 1);
strcpy ((char*)& packet -> data [strlen ("packet")], "foo");
/* 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 (event.peer, 0, packet);
/* One could just use enet_host_service() instead. */
enet_host_flush (server);
break;
case ENET_EVENT_TYPE_RECEIVE:
printf ("A packet of length %u containing %s was received from %s on channel %u.\n",
event.packet -> dataLength,
event.packet -> data,
event.peer -> data,
event.channelID);
/* Clean up the packet now that we're done using it. */
enet_packet_destroy (event.packet);
break;
case ENET_EVENT_TYPE_DISCONNECT:
printf ("%s disconected.\n", event.peer -> data);
/* Reset the peer's client information. */
event.peer -> data = NULL;
}
}
}
}
~Host()
{
if(server)
{
enet_host_destroy(server);
server = NULL;
}
atexit (enet_deinitialize);
}
};
class Client
{
ENetAddress address;
ENetEvent event;
ENetPeer *peer;
ENetHost* client;
public:
Client()
:peer(NULL)
{
enet_initialize();
setupPeer();
}
void setupPeer()
{
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 */,
57600 / 8 /* 56K modem with 56 Kbps downstream bandwidth */,
14400 / 8 /* 56K modem with 14 Kbps upstream bandwidth */);
if (client == NULL)
{
fprintf (stderr,
"An error occurred while trying to create an ENet client host.\n");
exit (EXIT_FAILURE);
}
/* Connect to some.server.net:1234. */
enet_address_set_host (& address, "192.168.2.13");
address.port = 1721;
/* 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.\n");
exit (EXIT_FAILURE);
}
/* Wait up to 5 seconds for the connection attempt to succeed. */
if (enet_host_service (client, & event, 20000) > 0 &&
event.type == ENET_EVENT_TYPE_CONNECT)
{
std::cout << "Connection to some.server.net:1234 succeeded." << std::endl;
}
else
{
/* Either the 5 seconds are up or a disconnect event was */
/* received. Reset the peer in the event the 5 seconds */
/* had run out without any significant event. */
enet_peer_reset (peer);
puts ("Connection to some.server.net:1234 failed.");
}
}
void daLoop()
{
ENetPacket* packet;
/* Create a reliable packet of size 7 containing "packet\0" */
packet = enet_packet_create ("backet",
strlen ("backet") + 1,
ENET_PACKET_FLAG_RELIABLE);
/* Extend the packet so and append the string "foo", so it now */
/* contains "packetfoo\0" */
enet_packet_resize (packet, strlen ("backetfoo") + 1);
strcpy ((char*)& packet -> data [strlen ("backet")], "foo");
/* 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 (event.peer, 0, packet);
/* One could just use enet_host_service() instead. */
enet_host_flush (client);
while(true)
{
/* Wait up to 1000 milliseconds for an event. */
while (enet_host_service (client, & event, 1000) > 0)
{
ENetPacket * packet;
switch (event.type)
{
case ENET_EVENT_TYPE_RECEIVE:
printf ("A packet of length %u containing %s was received from %s on channel %u.\n",
event.packet -> dataLength,
event.packet -> data,
event.peer -> data,
event.channelID);
/* Clean up the packet now that we're done using it. */
enet_packet_destroy (event.packet);
break;
}
}
}
}
~Client()
{
atexit (enet_deinitialize);
}
};
int main()
{
std::string a;
std::cin >> a;
if(a == "host")
{
Host host;
host.daLoop();
}
else
{
Client c;
c.daLoop();
}
return 0;
}
I looked at some socket tutorials and they seemed a bit too low level.
I just need something that abstracts away the platform (eg, no WINSOCKS) and that has basic ability to keep track of connected clients and send them messages.
Thanks
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