Hooking a function

[JohnnyMapot]

Just want to call a function when another function is called.

Example:

OnFunctionRun(print, function()
print("Ran print!")
end)

print("Hello")

The function that appears to be the closest was debug.sethook() but seems like the wiki is outdated, arguments aren't valid.

[SneakySquid]

You'd have to detour the original function. Though I'm fairly certain this is an XY issue, what exactly are you trying to do with this?

[JohnnyMapot]

Oh yeah sorry, i forgot to mention. I can't detour the original function.

I know this is a lil stupid but i'm trying to test my anticheat. Wanted to do an anti-detour function.

[SneakySquid]

For that you could use debug.getinfo, jit.util.funcinfo, and check that all the arguments and returns are what they should be. You could also try to make the functions error inside a coroutine and use debug.traceback to see if it errored somewhere it shouldn't have.

[JohnnyMapot]

I already do that, but i additionally need to call a func whenever another func is called. Thanks still. :/

[Srlion]

local OwO = {}
local debug_getinfo = debug.getinfo
local function UwU()
local e = OwO[debug_getinfo(2, "f").func]
if (e) then
e()
end
end
debug.sethook(UwU, "c")

local OnFunctionRun = function(fn, callback)
OwO[fn] = callback
end

OnFunctionRun(print, function()
print("Ran print!")
end)

[JohnnyMapot]

Exactly what i needed, thanks a lot!

[maarvin]

Correct me if I'm wrong but when a function is jit compiled debug.sethook callbacks wont be invoked.

If that is the case a good solution would be to call 'jit.off' and 'jit.flush', then 'jit.on' when you're done.