diff --git a/mesecons/util.lua b/mesecons/util.lua index e467aee..2514a87 100644 --- a/mesecons/util.lua +++ b/mesecons/util.lua @@ -234,6 +234,24 @@ function mesecon.tablecopy(obj) -- deep copy return obj end +-- Performs a deep copy of a table, changing the environment of any functions. +-- Adapted from the builtin table.copy() function. +function mesecon.tablecopy_change_env(t, env, seen) + local n = {} + seen = seen or {} + seen[t] = n + for k, v in pairs(t) do + if type(v) == "function" then + setfenv(v, env) + n[(type(k) == "table" and (seen[k] or mesecon.tablecopy_change_env(k, env, seen))) or k] = v + else + n[(type(k) == "table" and (seen[k] or mesecon.tablecopy_change_env(k, env, seen))) or k] = + (type(v) == "table" and (seen[v] or mesecon.tablecopy_change_env(v, env, seen))) or v + end + end + return n +end + -- Returns whether two values are equal. -- In tables, keys are compared for identity but values are compared recursively. -- There is no protection from infinite recursion. diff --git a/mesecons_luacontroller/init.lua b/mesecons_luacontroller/init.lua index 90516c0..21173d8 100644 --- a/mesecons_luacontroller/init.lua +++ b/mesecons_luacontroller/init.lua @@ -479,6 +479,24 @@ local function get_digiline_send(pos, itbl, send_warning) end end +-- Mods can place their own "libraries" in here to be loaded via require() from in a Luacontroller. +-- These can take two different forms: +-- Function (recommended for libraries adding new functionality): A function that, when called, returns something that will be passed to the LuaC code. +-- Function signature is getlibrary(env, pos) where 'env' is the environment that the Luacontroller code is running in, and 'pos' is the position of the controller. +-- Table (recommended for libraries containing mostly lookup tables): A table that will be copied, and the copy returned to the LuaC code. +-- When using the table format, any functions in the table will have their environment changed to that of the Luacontroller. +mesecon.luacontroller_libraries = {} + +local function get_require(pos, env) + return function(name) + if type(mesecon.luacontroller_libraries[name]) == "function" then + return mesecon.luacontroller_libraries[name](env, pos) + elseif type(mesecon.luacontroller_libraries[name]) == "table" then + return mesecon.tablecopy_change_env(mesecon.luacontroller_libraries[name], env) + end + end +end + local safe_globals = { -- Don't add pcall/xpcall unless willing to deal with the consequences (unless very careful, incredibly likely to allow killing server indirectly) "assert", "error", "ipairs", "next", "pairs", "select", @@ -572,6 +590,8 @@ local function create_environment(pos, mem, event, itbl, send_warning) for _, name in pairs(safe_globals) do env[name] = _G[name] end + + env.require = get_require(pos, env) return env end