37 lines
829 B
Lua
37 lines
829 B
Lua
--this version actually works
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local tab = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'
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base64 = {
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enc = function(data)
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local l,out = 0,''
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local m = (3-data:len()%3)%3
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local d = data..string.rep('\0',m)
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for i=1,d:len() do
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l = bit.lshift(l,8)
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l = l+d:byte(i,i)
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if i%3==0 then
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for j=1,4 do
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local a = bit.rshift(l,18)+1
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out = out..tab:sub(a,a)
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l = bit.band(bit.lshift(l,6),0xFFFFFF)
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end
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end
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end
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return out:sub(1,-1-m)..string.rep('=',m)
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end,
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dec = function(data)
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local a,b = data:gsub('=','A')
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local out = ''
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local l = 0
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for i=1,a:len() do
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l=l+tab:find(a:sub(i,i))-1
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if i%4==0 then
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out=out..string.char(bit.rshift(l,16),bit.band(bit.rshift(l,8),255),bit.band(l,255))
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l=0
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end
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l=bit.lshift(l,6)
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end
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return out:sub(1,-b-1)
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end
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}
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