38 lines
1.1 KiB
Lua
38 lines
1.1 KiB
Lua
local b='ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/' -- You will need this for encoding/decoding
|
|
-- encoding
|
|
local function enc(data)
|
|
return ((data:gsub('.', function(x)
|
|
local r,b='',x:byte()
|
|
for i=8,1,-1 do r=r..(b%2^i-b%2^(i-1)>0 and '1' or '0') end
|
|
return r;
|
|
end)..'0000'):gsub('%d%d%d?%d?%d?%d?', function(x)
|
|
if (#x < 6) then return '' end
|
|
local c=0
|
|
for i=1,6 do c=c+(x:sub(i,i)=='1' and 2^(6-i) or 0) end
|
|
return b:sub(c+1,c+1)
|
|
end)..({ '', '==', '=' })[#data%3+1])
|
|
end
|
|
|
|
-- decoding
|
|
local function dec(data)
|
|
data = string.gsub(data, '[^'..b..'=]', '')
|
|
return (data:gsub('.', function(x)
|
|
if (x == '=') then return '' end
|
|
local r,f='',(b:find(x)-1)
|
|
for i=6,1,-1 do r=r..(f%2^i-f%2^(i-1)>0 and '1' or '0') end
|
|
return r;
|
|
end):gsub('%d%d%d?%d?%d?%d?%d?%d?', function(x)
|
|
if (#x ~= 8) then return '' end
|
|
local c=0
|
|
for i=1,8 do c=c+(x:sub(i,i)=='1' and 2^(8-i) or 0) end
|
|
return string.char(c)
|
|
end))
|
|
end
|
|
|
|
auBase64 =
|
|
{
|
|
encode = enc,
|
|
decode = dec
|
|
}
|
|
|
|
_G["base64"] = auBase64 |