GameNetworkingSockets/tests/test_p2p.cpp

#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <string>
#include <random>
#include <chrono>
#include <thread>

#include "test_common.h"

#include <steam/steamnetworkingsockets.h>
#include <steam/isteamnetworkingutils.h>
#include "../examples/trivial_signaling_client.h"

HSteamListenSocket g_hListenSock;
HSteamNetConnection g_hConnection;
enum ETestRole
{
	k_ETestRole_Undefined,
	k_ETestRole_Server,
	k_ETestRole_Client,
	k_ETestRole_Symmetric,
};
ETestRole g_eTestRole = k_ETestRole_Undefined;

int g_nVirtualPortLocal = 0; // Used when listening, and when connecting
int g_nVirtualPortRemote = 0; // Only used when connecting

void OnSteamNetConnectionStatusChanged( SteamNetConnectionStatusChangedCallback_t *pInfo )
{
	// What's the state of the connection?
	switch ( pInfo->m_info.m_eState )
	{
	case k_ESteamNetworkingConnectionState_ClosedByPeer:
	case k_ESteamNetworkingConnectionState_ProblemDetectedLocally:

		TEST_Printf( "[%s] %s, reason %d: %s\n",
			pInfo->m_info.m_szConnectionDescription,
			( pInfo->m_info.m_eState == k_ESteamNetworkingConnectionState_ClosedByPeer ? "closed by peer" : "problem detected locally" ),
			pInfo->m_info.m_eEndReason,
			pInfo->m_info.m_szEndDebug
		);

		// Close our end
		SteamNetworkingSockets()->CloseConnection( pInfo->m_hConn, 0, nullptr, false );

		if ( g_hConnection == pInfo->m_hConn )
		{
			g_hConnection = k_HSteamNetConnection_Invalid;
		}
		else
		{
			// Why are we hearing about any another connection?
			assert( false );
		}

		break;

	case k_ESteamNetworkingConnectionState_None:
		// Notification that a connection was destroyed.  (By us, presumably.)
		// We don't need this, so ignore it.
		break;

	case k_ESteamNetworkingConnectionState_Connecting:

		// Is this a connection we initiated, or one that we are receiving?
		if ( g_hListenSock != k_HSteamListenSocket_Invalid && pInfo->m_info.m_hListenSocket == g_hListenSock )
		{
			// Somebody's knocking
			TEST_Printf( "[%s] Accepting\n", pInfo->m_info.m_szConnectionDescription );
			g_hConnection = pInfo->m_hConn;
			SteamNetworkingSockets()->AcceptConnection( pInfo->m_hConn );
		}
		else
		{
			// Note that we will get notification when our own connection that
			// we initiate enters this state.
		}
		break;

	case k_ESteamNetworkingConnectionState_FindingRoute:
		// P2P connections will spend a bried time here where they swap addresses
		// and try to find a route.
		TEST_Printf( "[%s] finding route\n", pInfo->m_info.m_szConnectionDescription );
		break;

	case k_ESteamNetworkingConnectionState_Connected:
		// We got fully connected
		assert( pInfo->m_hConn == g_hConnection ); // We don't initiate or accept any other connections, so this should be out own connection
		TEST_Printf( "[%s] connected\n", pInfo->m_info.m_szConnectionDescription );
		break;

	default:
		assert( false );
		break;
	}
}


int main( int argc, const char **argv )
{
	SteamNetworkingIdentity identityLocal; identityLocal.Clear();
	SteamNetworkingIdentity identityRemote; identityRemote.Clear();
	const char *pszTrivialSignalingService = "localhost:10000";

	// Parse the command line
	for ( int idxArg = 1 ; idxArg < argc ; ++idxArg )
	{
		const char *pszSwitch = argv[idxArg];

		auto GetArg = [&]() -> const char * {
			if ( idxArg + 1 >= argc )
				TEST_Fatal( "Expected argument after %s", pszSwitch );
			return argv[++idxArg];
		};
		auto ParseIdentity = [&]( SteamNetworkingIdentity &x ) {
			const char *pszArg = GetArg();
			if ( !x.ParseString( pszArg ) )
				TEST_Fatal( "'%s' is not a valid identity string", pszArg );
		};

		if ( !strcmp( pszSwitch, "--identity-local" ) )
			ParseIdentity( identityLocal );
		else if ( !strcmp( pszSwitch, "--identity-remote" ) )
			ParseIdentity( identityRemote );
		else if ( !strcmp( pszSwitch, "--signaling-server" ) )
			pszTrivialSignalingService = GetArg();
		else if ( !strcmp( pszSwitch, "--client" ) )
			g_eTestRole = k_ETestRole_Client;
		else if ( !strcmp( pszSwitch, "--server" ) )
			g_eTestRole = k_ETestRole_Server;
		else if ( !strcmp( pszSwitch, "--symmetric" ) )
			g_eTestRole = k_ETestRole_Symmetric;
		else
			TEST_Fatal( "Unexpected command line argument '%s'", pszSwitch );
	}

	if ( g_eTestRole == k_ETestRole_Undefined )
		TEST_Fatal( "Must specify test role (--server, --client, or --symmetric" );
	if ( identityLocal.IsInvalid() )
		TEST_Fatal( "Must specify local identity using --identity-local" );
	if ( identityRemote.IsInvalid() && g_eTestRole != k_ETestRole_Server )
		TEST_Fatal( "Must specify remote identity using --identity-remote" );

	// Initialize library, with the desired local identity
	TEST_Init( &identityLocal );

	// Create the signaling service
	SteamNetworkingErrMsg errMsg;
	ITrivialSignalingClient *pSignaling = CreateTrivialSignalingClient( pszTrivialSignalingService, SteamNetworkingSockets(), errMsg );
	if ( pSignaling == nullptr )
		TEST_Fatal( "Failed to initializing signaling client.  %s", errMsg );

	SteamNetworkingUtils()->SetGlobalCallback_SteamNetConnectionStatusChanged( OnSteamNetConnectionStatusChanged );

	// Create listen socket to receive connections on, unless we are the client
	if ( g_eTestRole == k_ETestRole_Server )
	{
		TEST_Printf( "Creating listen socket, local virtual port %d\n", g_nVirtualPortLocal );
		g_hListenSock = SteamNetworkingSockets()->CreateListenSocketP2P( g_nVirtualPortLocal, 0, nullptr );
		assert( g_hListenSock != k_HSteamListemSocket_Invalid );
	}
	else if ( g_eTestRole == k_ETestRole_Symmetric )
	{

		// Currently you must create a listen socket to use symmetric mode,
		// even if you know that you will always create connections "both ways".
		// In the future we might try to remove this requirement.  It is a bit
		// less efficient, since it always triggered the race condition case
		// where both sides create their own connections, and then one side
		// decides to their theirs away.  If we have a listen socket, then
		// it can be the case that one peer will receive the incoming connection
		// from the other peer, and since he has a listen socket, can save
		// the connection, and then implicitly accept it when he initiates his
		// own connection.  Without the listen socket, if an incoming connection
		// request arrives before we have started connecting out, then we are forced
		// to ignore it, as the app has given no indication that it desires to
		// receive inbound connections at all.
		TEST_Printf( "Creating listen socket in symmetric mode, local virtual port %d\n", g_nVirtualPortLocal );
		SteamNetworkingConfigValue_t opt;
		opt.SetInt32( k_ESteamNetworkingConfig_SymmetricConnect, 1 ); // << Note we set symmetric mode on the listen socket
		g_hListenSock = SteamNetworkingSockets()->CreateListenSocketP2P( g_nVirtualPortLocal, 1, &opt );
		assert( g_hListenSock != k_HSteamListemSocket_Invalid );
	}

	// Begin connecting to peer, unless we are the server
	if ( g_eTestRole != k_ETestRole_Server )
	{
		std::vector< SteamNetworkingConfigValue_t > vecOpts;

		// If we want the local and virtual port to differ, we must set
		// an option.  This is a pretty rare use case, and usually not needed.
		// The local virtual port is only usually relevant for symmetric
		// connections, and then, it almost always matches.  Here we are
		// just showing in this example code how you could handle this if you
		// needed them to differ.
		if ( g_nVirtualPortRemote != g_nVirtualPortLocal )
		{
			SteamNetworkingConfigValue_t opt;
			opt.SetInt32( k_ESteamNetworkingConfig_LocalVirtualPort, g_nVirtualPortLocal );
			vecOpts.push_back( opt );
		}

		// Symmetric mode?  Noce that since we created a listen socket on this local
		// virtual port and tagged it for symmetric connect mode, any connections
		// we create that use the same local virtual port will automatically inherit
		// this setting.  However, this is really not recommended.  It is best to be
		// explicit.
		if ( g_eTestRole == k_ETestRole_Symmetric )
		{
			SteamNetworkingConfigValue_t opt;
			opt.SetInt32( k_ESteamNetworkingConfig_SymmetricConnect, 1 );
			vecOpts.push_back( opt );
			TEST_Printf( "Connecting to '%s' in symmetric mode, virtual port %d, from local virtual port %d.\n",
				SteamNetworkingIdentityRender( identityRemote ).c_str(), g_nVirtualPortRemote,
				g_nVirtualPortLocal );
		}
		else
		{
			TEST_Printf( "Connecting to '%s', virtual port %d, from local virtual port %d.\n",
				SteamNetworkingIdentityRender( identityRemote ).c_str(), g_nVirtualPortRemote,
				g_nVirtualPortLocal );
		}

		// Connect using the "custom signaling" path.  Note that when
		// you are using this path, the identity is actually optional,
		// since we don't need it.  (Your signaling object already
		// knows how to talk to the peer) and then the peer identity
		// will be confirmed via rendezvous.
		SteamNetworkingErrMsg errMsg;
		ISteamNetworkingConnectionCustomSignaling *pConnSignaling = pSignaling->CreateSignalingForConnection(
			identityRemote,
			nullptr,
			errMsg
		);
		assert( pConnSignaling );
		g_hConnection = SteamNetworkingSockets()->ConnectP2PCustomSignaling( pConnSignaling, &identityRemote, g_nVirtualPortRemote, (int)vecOpts.size(), vecOpts.data() );
	}

	// Main test loop
	for (;;)
	{
		// Check for incoming signals, and dispatch them
		pSignaling->Poll();

		// Check callbacks
		TEST_PumpCallbacks();
	}


	TEST_Kill();	
	return 0;
}