PsychOSPackages/serialization.lua

51 lines
1.9 KiB
Lua

local serial = {}
local local_pairs=function(tbl)
local mt=getmetatable(tbl)
return (mt and mt.__pairs or pairs)(tbl)
end
function serial.serialize(value,af) -- boolean -- string -- serialize *value* into a string. If *af* is true, allow functions. This breaks unserialization.
local kw={["and"]=true,["break"]=true,["do"]=true,["else"]=true,["elseif"]=true,["end"]=true,["false"]=true,["for"]=true,["function"]=true,["goto"]=true,["if"]=true,["in"]=true,["local"]=true,["nil"]=true,["not"]=true,["or"]=true,["repeat"]=true,["return"]=true,["then"]=true,["true"]=true,["until"]=true,["while"]=true}
local id="^[%a_][%w_]*$"
local ts={}
local function s(v,l)
local t=type(v)
if t=="nil" then return "nil"
elseif t=="boolean" then return v and "true" or "false"
elseif t=="number" then
if v~=v then return "0/0"
elseif v==math.huge then return "math.huge"
elseif v==-math.huge then return "-math.huge"
else return tostring(v) end
elseif t=="string" then return string.format("%q",v):gsub("\\\n","\\n")
elseif t=="table" then
if ts[v] then error("tcyc") end
ts[v]=true
local i,r=1, nil
local f=table.pack(local_pairs(v))
for k,v in table.unpack(f) do
if r then r=r..","..(("\n"..string.rep(" ",l)) or "")
else r="{" end
local tk=type(k)
if tk=="number" and k==i then
i=i+1
r=r..s(v,l+1)
else
if tk == "string" and not kw[k] and string.match(k,id) then r=r..k
else r=r.."["..s(k,l+1).."]" end
r=r.."="..s(v,l+1) end end
ts[v]=nil
return (r or "{").."}"
elseif t=="function" and af then
return tostring(v)
else error("ut "..t) end end
return s(value, 1)
end
function serial.unserialize(data) -- string -- -- return *data*, but unserialized
local result, reason = load("return " .. data, "=data", _, {math={huge=math.huge}})
if not result then return nil, reason end
local ok, output = pcall(result)
if not ok then return nil, output end
return output
end
return serial