mediawiki-extensions-Scribunto/engines/LuaCommon/lualib/package.lua
Tim Starling 441943bd9b Do not allow access to setfenv() and getfenv() by default
Optionally remove setfenv and getfenv from the global environment in
which user code runs. This will improve the forwards-compatibility of
user code with Lua 5.2.

Porting to Lua 5.2 would still be a daunting project, of questionable
value, but at least only the internal code would need updating, and not
thousands of on-wiki modules. Compared to the environment changes, the
rest of the Lua 5.2 changes are relatively easy to simulate for
backwards compatibility.

Removed module() from the package module, since it depends on setfenv().
The native version of it is deprecated in Lua 5.2 for that reason.

Change-Id: I978903ca98943ac941833da13fe5027949f6b429
2012-05-31 15:02:04 +02:00

138 lines
3.9 KiB
Lua

--[[
-- A package library similar to the one that comes with Lua 5.1, but without
-- the local filesystem access. Based on Compat-5.1 which comes with the
-- following license notice:
--
-- Copyright © 2004-2006 The Kepler Project.
--
-- Permission is hereby granted, free of charge, to any person obtaining a copy of
-- this software and associated documentation files (the "Software"), to deal in
-- the Software without restriction, including without limitation the rights to
-- use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
-- the Software, and to permit persons to whom the Software is furnished to do so,
-- subject to the following conditions:
--
-- The above copyright notice and this permission notice shall be included in all
-- copies or substantial portions of the Software.
--
-- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-- IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
-- FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
-- COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
-- IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
-- CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
--]]
local assert, error, ipairs, pairs, setmetatable, type = assert, error, ipairs, pairs, setmetatable, type
local find, format, gfind, gsub, sub = string.find, string.format, string.gfind, string.gsub, string.sub
--
-- avoid overwriting the package table if it's already there
--
package = package or {}
local _PACKAGE = package
package.loaded = package.loaded or {}
local _LOADED = package.loaded
--
-- avoid overwriting the package.preload table if it's already there
--
package.preload = package.preload or {}
local _PRELOAD = package.preload
--
-- check whether library is already loaded
--
local function loader_preload (name)
assert (type(name) == "string", format (
"bad argument #1 to `require' (string expected, got %s)", type(name)))
assert (type(_PRELOAD) == "table", "`package.preload' must be a table")
return _PRELOAD[name]
end
-- create `loaders' table
package.loaders = package.loaders or { loader_preload }
local _LOADERS = package.loaders
--
-- iterate over available loaders
--
local function load (name, loaders)
-- iterate over available loaders
assert (type (loaders) == "table", "`package.loaders' must be a table")
for i, loader in ipairs (loaders) do
local f = loader (name)
if f then
return f
end
end
error (format ("module `%s' not found", name))
end
-- sentinel
local sentinel = function () end
--
-- require
--
function _G.require (modname)
assert (type(modname) == "string", format (
"bad argument #1 to `require' (string expected, got %s)", type(name)))
local p = _LOADED[modname]
if p then -- is it there?
if p == sentinel then
error (format ("loop or previous error loading module '%s'", modname))
end
return p -- package is already loaded
end
local init = load (modname, _LOADERS)
_LOADED[modname] = sentinel
local actual_arg = _G.arg
_G.arg = { modname }
local res = init (modname)
if res then
_LOADED[modname] = res
end
_G.arg = actual_arg
if _LOADED[modname] == sentinel then
_LOADED[modname] = true
end
return _LOADED[modname]
end
-- findtable
local function findtable (t, f)
assert (type(f)=="string", "not a valid field name ("..tostring(f)..")")
local ff = f.."."
local ok, e, w = find (ff, '(.-)%.', 1)
while ok do
local nt = rawget (t, w)
if not nt then
nt = {}
t[w] = nt
elseif type(t) ~= "table" then
return sub (f, e+1)
end
t = nt
ok, e, w = find (ff, '(.-)%.', e+1)
end
return t
end
--
-- package.seeall function
--
function _PACKAGE.seeall (module)
local t = type(module)
assert (t == "table", "bad argument #1 to package.seeall (table expected, got "..t..")")
local meta = getmetatable (module)
if not meta then
meta = {}
setmetatable (module, meta)
end
meta.__index = _G
end