166 lines
5.3 KiB
Lua
166 lines
5.3 KiB
Lua
----------------
|
|
--- Lua 5.1/5.2/5.3 compatibility.
|
|
-- Ensures that `table.pack` and `package.searchpath` are available
|
|
-- for Lua 5.1 and LuaJIT.
|
|
-- The exported function `load` is Lua 5.2 compatible.
|
|
-- `compat.setfenv` and `compat.getfenv` are available for Lua 5.2, although
|
|
-- they are not always guaranteed to work.
|
|
-- @module pl.compat
|
|
|
|
local compat = {}
|
|
|
|
compat.lua51 = _VERSION == 'Lua 5.1'
|
|
|
|
local isJit = (tostring(assert):match('builtin') ~= nil)
|
|
if isJit then
|
|
-- 'goto' is a keyword when 52 compatibility is enabled in LuaJit
|
|
compat.jit52 = not loadstring("local goto = 1")
|
|
end
|
|
|
|
compat.dir_separator = _G.package.config:sub(1,1)
|
|
compat.is_windows = compat.dir_separator == '\\'
|
|
|
|
--- execute a shell command.
|
|
-- This is a compatibility function that returns the same for Lua 5.1 and Lua 5.2
|
|
-- @param cmd a shell command
|
|
-- @return true if successful
|
|
-- @return actual return code
|
|
function compat.execute (cmd)
|
|
local res1,_,res3 = os.execute(cmd)
|
|
if compat.lua51 and not compat.jit52 then
|
|
if compat.is_windows then
|
|
res1 = res1 > 255 and res1 % 256 or res1
|
|
return res1==0,res1
|
|
else
|
|
res1 = res1 > 255 and res1 / 256 or res1
|
|
return res1==0,res1
|
|
end
|
|
else
|
|
if compat.is_windows then
|
|
res3 = res3 > 255 and res3 % 256 or res3
|
|
return res3==0,res3
|
|
else
|
|
return not not res1,res3
|
|
end
|
|
end
|
|
end
|
|
|
|
----------------
|
|
-- Load Lua code as a text or binary chunk.
|
|
-- @param ld code string or loader
|
|
-- @param[opt] source name of chunk for errors
|
|
-- @param[opt] mode 'b', 't' or 'bt'
|
|
-- @param[opt] env environment to load the chunk in
|
|
-- @function compat.load
|
|
|
|
---------------
|
|
-- Get environment of a function.
|
|
-- With Lua 5.2, may return nil for a function with no global references!
|
|
-- Based on code by [Sergey Rozhenko](http://lua-users.org/lists/lua-l/2010-06/msg00313.html)
|
|
-- @param f a function or a call stack reference
|
|
-- @function compat.getfenv
|
|
|
|
---------------
|
|
-- Set environment of a function
|
|
-- @param f a function or a call stack reference
|
|
-- @param env a table that becomes the new environment of `f`
|
|
-- @function compat.setfenv
|
|
|
|
if compat.lua51 then -- define Lua 5.2 style load()
|
|
if not isJit then -- but LuaJIT's load _is_ compatible
|
|
local lua51_load = load
|
|
function compat.load(str,src,mode,env)
|
|
local chunk,err
|
|
if type(str) == 'string' then
|
|
if str:byte(1) == 27 and not (mode or 'bt'):find 'b' then
|
|
return nil,"attempt to load a binary chunk"
|
|
end
|
|
chunk,err = loadstring(str,src)
|
|
else
|
|
chunk,err = lua51_load(str,src)
|
|
end
|
|
if chunk and env then setfenv(chunk,env) end
|
|
return chunk,err
|
|
end
|
|
else
|
|
compat.load = load
|
|
end
|
|
compat.setfenv, compat.getfenv = setfenv, getfenv
|
|
else
|
|
compat.load = load
|
|
-- setfenv/getfenv replacements for Lua 5.2
|
|
-- by Sergey Rozhenko
|
|
-- http://lua-users.org/lists/lua-l/2010-06/msg00313.html
|
|
-- Roberto Ierusalimschy notes that it is possible for getfenv to return nil
|
|
-- in the case of a function with no globals:
|
|
-- http://lua-users.org/lists/lua-l/2010-06/msg00315.html
|
|
function compat.setfenv(f, t)
|
|
f = (type(f) == 'function' and f or debug.getinfo(f + 1, 'f').func)
|
|
local name
|
|
local up = 0
|
|
repeat
|
|
up = up + 1
|
|
name = debug.getupvalue(f, up)
|
|
until name == '_ENV' or name == nil
|
|
if name then
|
|
debug.upvaluejoin(f, up, function() return name end, 1) -- use unique upvalue
|
|
debug.setupvalue(f, up, t)
|
|
end
|
|
if f ~= 0 then return f end
|
|
end
|
|
|
|
function compat.getfenv(f)
|
|
local f = f or 0
|
|
f = (type(f) == 'function' and f or debug.getinfo(f + 1, 'f').func)
|
|
local name, val
|
|
local up = 0
|
|
repeat
|
|
up = up + 1
|
|
name, val = debug.getupvalue(f, up)
|
|
until name == '_ENV' or name == nil
|
|
return val
|
|
end
|
|
end
|
|
|
|
--- Lua 5.2 Functions Available for 5.1
|
|
-- @section lua52
|
|
|
|
--- pack an argument list into a table.
|
|
-- @param ... any arguments
|
|
-- @return a table with field n set to the length
|
|
-- @function table.pack
|
|
if not table.pack then
|
|
function table.pack (...) -- luacheck: ignore
|
|
return {n=select('#',...); ...}
|
|
end
|
|
end
|
|
|
|
--- unpack a table and return the elements.
|
|
-- @param t table to unpack
|
|
-- @param[opt] i index from which to start unpacking, defaults to 1
|
|
-- @param[opt] t index of the last element to unpack, defaults to #t
|
|
-- @return multiple returns values from the table
|
|
if not table.unpack then
|
|
table.unpack = unpack -- luacheck: ignore
|
|
end
|
|
|
|
------
|
|
-- return the full path where a Lua module name would be matched.
|
|
-- @param mod module name, possibly dotted
|
|
-- @param path a path in the same form as package.path or package.cpath
|
|
-- @see path.package_path
|
|
-- @function package.searchpath
|
|
if not package.searchpath then
|
|
local sep = package.config:sub(1,1)
|
|
function package.searchpath (mod,path) -- luacheck: ignore
|
|
mod = mod:gsub('%.',sep)
|
|
for m in path:gmatch('[^;]+') do
|
|
local nm = m:gsub('?',mod)
|
|
local f = io.open(nm,'r')
|
|
if f then f:close(); return nm end
|
|
end
|
|
end
|
|
end
|
|
|
|
return compat
|