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!Lua #!/usr/bin/env lua -- Lua 5.1+ base64 v3.0 (c) 2009 by Alex Kloss <> -- licensed under the terms of the LGPL2

-- character table string local b='ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'

-- encoding 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 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

-- command line if not called as library if (arg ~= nil) then

local func = 'enc'
for n,v in ipairs(arg) do
if (n > 0) then
if (v == "-h") then print "base64.lua [-e] [-d] text/data" break
elseif (v == "-e") then func = 'enc'
elseif (v == "-d") then func = 'dec'
else print(_G[func](v)) end
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Last edited September 6, 2014 4:18 am GMT (diff)