QTS no. 11 - Register logging detour

/*
-----------------------------------------
* Game hacking QTS ( Quickie Tip Series )
* no. 11 - Register logging detour
-----------------------------------------
* Author: SEGnosis  - GHAnon.net
* Thanks to:
* bitterbanana      - No known site
* Drunken Cheetah   - No known site
* fatboy88      - No known site
* Geek4Ever         - No known site
* learn_more        - www.uc-forum.com
* Novocaine         - http://ilsken.net/blog/?page_id=64
* Philly0494        - No known site
* Roverturbo        - www.uc-forum.com
* SilentKarma       - www.halocoders.com - offline
* Strife        - www.uc-forum.com
* Wieter20      - No known site
*/

DWORD dwRet     = 0x00000000; // return address
DWORD dwJumpAddress     = 0x00000000; // address to detour
//----------------------------------//
__declspec(naked) void DetourFunction() // naked to avoid precompiled header and footer
{
    __asm
    {
        // Original instructions here
        pushad // preserve state
        pushfd

        // log registers to variables here
    }

    // call functions here

    __asm
    {
        popfd // return states
        popad
        jmp [dwRet] // return flow to address indicated
    }
}//----------------------------------//

//----------------------------------//
void DetourLogger( void )
{
    BYTE cHook[ 5 ] = { 0xe9, 0, 0, 0, 0 }; // jump instruction with space for offset

    DWORD dwFunction = ( DWORD )DetourFunction - dwJumpAddress - 5; // offset for jump instruction
    memcpy( &cHook[ 1 ], &dwFunction, 4 ); // move offset into array

    DWORD dwOld;
    VirtualProtect( ( PVOID )dwJumpAddress, 5, PAGE_EXECUTE_READWRITE, &dwOld ); // open memory for modification
    memcpy( ( PVOID )dwJumpAddress, &cHook, 5 ); // move instruction
    VirtualProtect( ( PVOID )dwJumpAddress, 5, dwOld, 0 ); // return permissions
}
//----------------------------------//

// The best way to do this would be to make the function take parameters for function to detour
// Have it copy and append the original instructions before jumping to the actual detour function