Module:Base64: Difference between revisions
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args = frame |
args = frame |
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end |
end |
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data = args.data |
data = frame.args.data |
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encode = args.encode |
encode = frame.args.encode |
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yesno(encode, false) |
yesno(encode, false) |
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return "Sorry, I gave up that time" |
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local index_table = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/' |
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function to_binary(integer) |
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local remaining = tonumber(integer) |
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local bin_bits = '' |
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for i = 7, 0, -1 do |
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local current_power = 2 ^ i |
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if remaining >= current_power then |
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bin_bits = bin_bits .. '1' |
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remaining = remaining - current_power |
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else |
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bin_bits = bin_bits .. '0' |
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end |
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end |
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return bin_bits |
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end |
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function from_binary(bin_bits) |
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return tonumber(bin_bits, 2) |
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end |
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function to_base64(to_encode) |
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local bit_pattern = '' |
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local encoded = '' |
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local trailing = '' |
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for i = 1, string.len(to_encode) do |
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bit_pattern = bit_pattern .. to_binary(string.byte(string.sub(to_encode, i, i))) |
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end |
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-- Check the number of bytes. If it's not evenly divisible by three, |
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-- zero-pad the ending & append on the correct number of ``=``s. |
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if string.len(bit_pattern) % 3 == 2 then |
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trailing = '==' |
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bit_pattern = bit_pattern .. '0000000000000000' |
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elseif string.len(bit_pattern) % 3 == 1 then |
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trailing = '=' |
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bit_pattern = bit_pattern .. '00000000' |
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end |
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for i = 1, string.len(bit_pattern), 6 do |
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local byte = string.sub(bit_pattern, i, i+5) |
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local offset = tonumber(from_binary(byte)) |
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encoded = encoded .. string.sub(index_table, offset+1, offset+1) |
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end |
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local result = string.sub(encoded, 1, -1 - string.len(trailing)) .. trailing |
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return(result) |
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end |
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function from_base64(to_decode) |
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local padded = to_decode:gsub("%s", "") |
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local unpadded = padded:gsub("=", "") |
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local bit_pattern = '' |
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local decoded = '' |
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for i = 1, string.len(unpadded) do |
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local char = string.sub(to_decode, i, i) |
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local offset, _ = string.find(index_table, char) |
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if offset == nil then |
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error("Invalid character '" .. char .. "' found.") |
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end |
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bit_pattern = bit_pattern .. string.sub(to_binary(offset-1), 3) |
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end |
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for i = 1, string.len(bit_pattern), 8 do |
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local byte = string.sub(bit_pattern, i, i+7) |
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decoded = decoded .. string.char(from_binary(byte)) |
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end |
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local padding_length = padded:len()-unpadded:len() |
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if (padding_length == 1 or padding_length == 2) then |
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decoded = decoded:sub(1,-2) |
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end |
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return decoded |
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end |
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if (encode == true) then |
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to_base64(data) |
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else |
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from_base64(data) |
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local result = data |
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return(result) |
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end |
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end |
end |
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Latest revision as of 15:48, 14 January 2021
Documentation for this module may be created at Module:Base64/doc
-- Made by [[User:Celeste]] - Licensed under GPLv3
local p = {}
local yesno = require('Module:Yesno') -- invoke Yesno
local b='ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/' -- You will need this for encoding/decoding
function p.base64(frame)
local args
local data
local encode
if frame == mw.getCurrentFrame() then
args = frame.args
else
args = frame
end
data = frame.args.data
encode = frame.args.encode
yesno(encode, false)
return "Sorry, I gave up that time"
end
return p