Win32 CodeHook

Document of interface IErrorCodeHook

This interface is intended to main a global error code.
All other hook interfaces implement this interface so you can use this interface directly in other interfaces.

Delphi syntax:

IErrorCodeHook = interface
	function GetErrorCode: Cardinal; stdcall;
	function GetErrorMessage(AMessage: PChar; AMessageLen: Integer): Integer; stdcall;
end;

C++ syntax:

class ICodeHookError: public IUnknown {
public:
	virtual UINT _stdcall GetErrorCode() = 0;
	virtual int _stdcall GetErrorMessage(char * Message, int MessageLen) = 0;
};

Function:

GetErrorCode

Retrieve the last error code.
Delphi syntax:

function GetErrorCode: Cardinal; stdcall;

C++ syntax:

virtual UINT calltype GetErrorCode() = 0;

Params

This function has no parameters.

Return value

The last error code.

Remarks

There are constants defined for error code. HEC_NONE: No error occured. HEC_FUNCTION_TOO_SMALL: The target function is too small to be hooked. That's to say, a 'ret' or 'iret' instruction is met in the first serveral instructions of the target. HEC_UNKNOWN_INSTRUCTION: An instruction can not be recognized by current disassembly engine. HEC_ADDRESS_CANNOT_WRITE: The destination address is read only and can't be written. HEC_INVALID_HANDLE: The handle passed in as a parameter is invalid. HEC_INVALID_CC: The calling convention passed in as a parameter is invalid. HEC_TOO_MANY_EXTRA_PARAMS: The extra parameters exceed the maximum count. The maximum count is MAX_EXTRA_PARAM_COUNT. HEC_EXTEND_INFO_UNAVAILABLE: Can't find extend information. That usually means you require advanced mode operation on raw mode hooking.

Function:

GetErrorMessage

Retrieve the last error message.
Delphi syntax:

function GetErrorMessage(AMessage: PChar; AMessageLen: Integer): Integer; stdcall;

C++ syntax:

virtual int calltype GetErrorMessage(char * Message, int MessageLen) = 0;

Params

AMessage: Pointer to the buffer to retrieve the message.
AMessageLen: The buffer length.

Return value

The byte count that copied to the buffer. If the buffer is too small, the message will be truncated.