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getfunctionhash

getfunctionhash returns the hex-represented SHA384 hash of a provided function's instructions (code) and constants.

C closures are not supported

This function will throw an error if called on a C closure, such as print, since C closures have no reliable information to hash. The error should be something along the lines of lua function expected

Notes on getfunctionhash

In order to have reliable knowledge over what the function changes, constants should also be added to the hash alongside the l.p->code. Add the constants at the beginning of the instructions, and hash that.

We suggest following this implementation in order to keep the same functionality across multiple executors, since it will be more convenient for the users not having to change their hashes if they do migrate to a different executor.

Full credits go to Dottik and Ragnar regarding the source provided above.

function getfunctionhash(functionToHash: (...any) -> (...any)): string

Parameters

Parameter Description
functionToHash The function to retrieve the hash of.

Example

Checking the SHA384 hash of functions with getfunctionhash
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local function is_sha384_hex(hash)
    return #hash == 96 and hash:match("^[0-9a-fA-F]+$") ~= nil
end

local dummy_function_0 = function() end
local dummy_function_1 = function(...) end
local dummy_function_2 = function() end
local dummy_function_3 = function() return "Constant" end
local dummy_function_4 = function() return "Constant2" end

print(is_sha384_hex(getfunctionhash(dummy_function_0))) -- Output: true
print(getfunctionhash(dummy_function_0) == getfunctionhash(dummy_function_1)) -- Output: false
print(getfunctionhash(dummy_function_0) == getfunctionhash(dummy_function_2)) -- Output: true
print(getfunctionhash(dummy_function_3) == getfunctionhash(dummy_function_4)) -- Output: false