/********************************************************************

Copyright 2006-2008 ZHANG Luduo. All Rights Reserved.

Permission to use, copy, modify, distribute and sell this software
and its documentation for any purpose is hereby granted without fee,
provided that the above copyright notice appear in all copies and
that both that copyright notice and this permission notice appear
in supporting documentation.

********************************************************************/

/*

代碼說明 : 

	thunk - 動態替換CPU指令
	利用這個類可以將Windows API的回調函數封裝
	成C++類成員.這份代碼只能在x86的CPU上執行.

聯系方式:

	作者  - 張魯奪
	MSN   - zhangluduo@msn.com
	Email - zhangluduo@163.com
	QQ群  - 34064264, 56918155

為所有愛我的人和我愛的人努力!

*/

#ifndef _THUNK_H
#define _THUNK_H

class Thunk  
{
private:

//	unsigned char m_ThiscallCode[10];
//	unsigned char m_StdcallCode [16];

	#pragma pack(push, 1)

		typedef struct		_THUNK_THISCALL
		{
			unsigned char	Mov;		// 0xB9
			unsigned long	This;		// this pointer
			unsigned char	Jmp;		// 0xE9
			unsigned long	Adrr;		// target address
		}	THUNK_THISCALL, *PTHUNK_THISCALL;

		typedef struct		_THUNK_STDCALL
		{
			unsigned char	Push[3];	// push dword ptr[esp] ;
			unsigned long	Move;		// mov	dword ptr [esp + 4], ?? ?? ?? ?? ;
			unsigned long	This;		// this pointer
			unsigned char	Jmp;		// 0xE9
			unsigned long	Adrr;		// target address
		}	THUNK_STDCALL, *PTHUNK_STDCALL;

	#pragma pack(pop)

	THUNK_THISCALL	m_THISCALL;
	THUNK_STDCALL	m_STDCALL;

public:

	template <typename T> 
	static unsigned long GetMemberFxnAddr(T MemberFxnName)
	{
		union { T _f; unsigned long _t; } ut;
		ut._f = MemberFxnName;
		return ut._t;
	}

	void* Thiscall(void* pThis, unsigned long MemberFxnAddr);

	void* Stdcall (void* pThis, unsigned long MemberFxnAddr);
};

#endif