gm_unrequire

C++ implementation of unrequire for GMod because its Lua variant doesn't work properly due to the removal of debug.getregistry

Lua variant

local is_windows = system.IsWindows()
local is_linux = system.IsLinux()
local is_osx = system.IsOSX()
local is_x64 = jit.arch == "x64"

local dll_prefix = CLIENT and "gmcl" or "gmsv"
local dll_suffix = assert(
    (is_windows and (is_x64 and "win64" or "win32")) or
    (is_linux and (is_x64 and "linux64" or "linux")) or
    (is_osx and (is_x64 and "osx64" or "osx"))
)

-- metaman (danielga) unrequire
do
    local _MODULES = _MODULES
    local package_loaded = package.loaded
    local _R = debug.getregistry()
    local _LOADLIB = _R._LOADLIB

    local separator = is_windows and "\\" or "/"

    local fmt = string.format(
        "^LOADLIB: .+%sgarrysmod%slua%sbin%s%s_%%s_%s.dll$",
        separator,
        separator,
        separator,
        separator,
        dll_prefix,
        dll_suffix
    )

    function unrequire(name)
        _MODULES[name] = nil
        package_loaded[name] = nil

        local loadlib = string.format(fmt, name)
        for name, mod in pairs(_R) do
            if type(name) == "string" and string.find(name, loadlib) then
                _LOADLIB.__gc(mod)
                _R[name] = nil
                break
            end
        end
    end
end