Cheat Engine

[oib111]

Nobody caught it, but you declared the array as BYTE[5] varname instead of BYTE varname[5].

[rapion124]

What you are trying to do is called inline hooking. You modify the execution flow of a program by placing a jmp instruction. Placing the hook is the easy part. Your actual hook function needs to have a few things: a way to return execution flow to the original code, proper understanding of registers and stack, and restoration of the overwritten instructions. If you don't have those things, your hook will fail and the program just crashes.

Here's my code to install an inline hook:

[oib111]

I know what inline hooking was. I was just wondering if I could apply the hotpatching method (replacing the first five bytes with a jump) for program defined functions. And your code could use some cleaning. It works, but it has lots of code that isn't needed, and bad ways of doing things.

[Dark Byte]

my preferred method:
Add a disassembler/assembler to your hooker. (write it yourself, or use a dll. Sure, the package will grow several KB's, but who cares? not me!)
Disassemble the start of the routine till you have at least 5 bytes.

Then let the assembler write the following:
originalcode (reassembled, so all relative jumps will be written successfully)
jmp "after the bytesyoudisassembled"

And then you can safely assemble a "jmp toyourhook" at the spot you want to hook.

Sure, it's not really advanced, and it's taking the easy way out, but hey, it works...

Just find yourself a good assembler/disassembler dll (and if you're bored, the ce source compile the assembler ,disassembler and even auto assembler as a dll if you do some minor changes and make new project files)

[Ferocious]

@HalfPrime : i've already edited my previous post, i've said that im sorry for the misleading infomation.