How to Network (Client and Server) Using a User-Defined Protocol

The following example demonstrates how to network (client and server) using a user-defined protocol. For an example of how to create a user-defined protocol, refer to How to Create a User-Defined Protocol.

The Server Side:

C Source

// To use the network protocol manager interface, use the following code 
// Note that the protocol manager interface will use the protocol 
// interface 
ILMNetProtocolManager* pProtocol; 
ILMNetConnectionPoint *pConnection = NULL; 
ILMNetConnection* pServerCon = NULL; 
BSTR strPeer; 
BYTE *pBuff = NULL; 
DWORD dSize; 
HRESULT hRes = CoCreateInstance(&CLSID_LMNetProtocolManager, NULL, CLSCTX_ALL, &IID_ILMNetProtocolManager, (void**)&pProtocol); 
if (FAILED(hRes)) 
   return; 
// Create the server connection point 
hRes = ILMNetProtocol_CreateConnectionPoint(pProtocol, L"myschema://10.0.4.2:27015", &pConnection); 
if (FAILED(hRes)) 
{ 
   ILMNetProtocol_Release(pProtocol); 
   return; 
} 
// Wait for the new incoming connection. 
do 
{ 
   ILMNetConnectionPoint_GetConnection(pConnection, &pServerCon, 1000); 
   Sleep(100); 
} while (pServerCon == NULL); 
// To check whether there is a connection, use the following code 
if (ILMNetConnection_IsConnected(pServerCon) != S_OK) 
{ 
   ILMNetConnection_Release(pServerCon); 
   ILMNetProtocol_Release(pProtocol); 
   return; 
} 
// Get the peer name (Client Name) 
ILMNetConnection_GetPeerName(pServerCon, &strPeer); 
// Free the string when no longer needed 
CoTaskMemFree(strPeer); 
// The server is now ready to send the data 
pBuff = (BYTE*)malloc(1024); 
dSize = 1024; 
ILMNetConnection_Send(pServerCon, pBuff, dSize, &dSize, 1000); 
// If there is any blocking call, call the CancelBlockingCall method 
ILMNetConnection_CancelBlockingCall(pServerCon); 
// To disconnect, call the Disconnect method 
ILMNetConnection_Disconnect(pServerCon); 
// Close the connection point 
ILMNetConnectionPoint_Close(pConnection); 
// Free the pointers 
free(pBuff); 
ILMNetConnection_Release(pServerCon); 
ILMNetProtocol_Release(pProtocol); 

C++ Source

// To use the network protocol manager interface, use the following code 
// Note that the protocol manager interface will use the protocol 
// interface 
ILMNetProtocolManager* pProtocol; 
HRESULT hRes = CoCreateInstance(CLSID_LMNetProtocolManager, NULL, CLSCTX_ALL, IID_ILMNetProtocolManager, (void**)&pProtocol); 
if (FAILED(hRes)) 
   return; 
// Create the server connection point 
ILMNetConnectionPoint *pConnection = NULL; 
hRes = pProtocol->CreateConnectionPoint(L"myschema://10.0.4.2:27015", &pConnection); 
if (FAILED(hRes)) 
{ 
   pProtocol->Release(); 
   return; 
} 
// Wait for the new incoming connection. 
ILMNetConnection* pServerCon = NULL; 
do 
{ 
   pConnection->GetConnection(&pServerCon, 1000); 
   Sleep(100); 
} while (pServerCon == NULL); 
// To check whether there is a connection, use the following code 
if (pServerCon->IsConnected() != S_OK) 
{ 
   pServerCon->Release(); 
   pProtocol->Release(); 
   return; 
} 
// Get the  peer name (Client Name) 
BSTR strPeer; 
pServerCon->GetPeerName(&strPeer); 
// Free the string when no longer needed 
CoTaskMemFree(strPeer); 
// The server is now ready to send the data 
BYTE *pBuff = new BYTE[1024]; 
DWORD dSize = 1024; 
pServerCon->Send(pBuff, dSize, &dSize, 1000); 
// If there is any blocking call, call the CancelBlockingCall method 
pServerCon->CancelBlockingCall(); 
// To disconnect, call the Disconnect method 
pServerCon->Disconnect(); 
// Close the connection point 
pConnection->Close(); 
// Free the pointers 
delete[] pBuff; 
pServerCon->Release(); 
pProtocol->Release(); 

The Client Side:

C Source

ILMNetProtocolManager* pProtocol; 
ILMNetConnection* pClientCon; 
BSTR strPeer; 
BYTE *pBuff; 
DWORD dSize; 
HRESULT hRes; 
// To use the network protocol manager interface, use the following code 
// Note that the protocol manager interface will use the protocol 
// interface 
hRes = CoCreateInstance(&CLSID_LMNetProtocolManager, NULL, CLSCTX_ALL, &IID_ILMNetProtocolManager, (void**)&pProtocol); 
if (FAILED(hRes)) 
   return; 
// Connect to the server 
hRes = ILMNetProtocol_Connect(pProtocol, L"myschema://10.0.4.2:27015", &pClientCon, 1000); 
if (FAILED(hRes)) 
{ 
   ILMNetProtocol_Release(pProtocol); 
   return; 
} 
// To check whether there is a connection, use the following code 
if (ILMNetConnection_IsConnected(pClientCon) != S_OK) 
{ 
   ILMNetConnection_Release(pClientCon); 
   ILMNetProtocol_Release(pProtocol); 
   return; 
} 
// Get the  peer name (Server Name) 
ILMNetConnection_GetPeerName(pClientCon, &strPeer); 
// Free the string when no longer needed 
CoTaskMemFree(strPeer); 
// The client is now ready to receive the data 
pBuff = (BYTE*)malloc(1024); 
dSize = 1024; 
ILMNetConnection_Recv(pClientCon, pBuff, dSize, &dSize, 1000); 
// If there is any blocking call, call the CancelBlockingCall method 
ILMNetConnection_CancelBlockingCall(pClientCon); 
// To disconnect, call the Disconnect method 
ILMNetConnection_Disconnect(pClientCon); 
// Free the pointers 
free(pBuff); 
ILMNetConnection_Release(pClientCon); 
ILMNetProtocol_Release(pProtocol); 

C++ Source

// To use the network protocol manager interface, use the following code 
// Note that the protocol manager interface will use the protocol 
// interface 
ILMNetProtocolManager* pProtocol; 
HRESULT hRes = CoCreateInstance(CLSID_LMNetProtocolManager, NULL, CLSCTX_ALL, IID_ILMNetProtocolManager, (void**)&pProtocol); 
if (FAILED(hRes)) 
   return; 
// Connect to the server 
ILMNetConnection* pClientCon; 
hRes = pProtocol->Connect(L"myschema://10.0.4.2:27015", &pClientCon, 1000); 
if (FAILED(hRes)) 
{ 
   pProtocol->Release(); 
   return; 
} 
// To check whether there is a connection, use the following code 
if (pClientCon->IsConnected() != S_OK) 
{ 
   pClientCon->Release(); 
   pProtocol->Release(); 
   return; 
} 
// Get the  peer name (Server Name) 
BSTR strPeer; 
pClientCon->GetPeerName(&strPeer); 
// Free the string when no longer needed 
CoTaskMemFree(strPeer); 
// The client is now ready to receive the data 
BYTE *pBuff = new BYTE[1024]; 
DWORD dSize = 1024; 
pClientCon->Recv(pBuff, dSize, &dSize, 1000); 
// If there is any blocking call, call the CancelBlockingCall method 
pClientCon->CancelBlockingCall(); 
// To disconnect, call the Disconnect method 
pClientCon->Disconnect(); 
// Free the pointers 
delete[] pBuff; 
pClientCon->Release(); 
pProtocol->Release(); 

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