Write or draw as you like, then export to html and clear to write or draw again. There's no way to maintain more than one file. There's no way to reimport the exported html.
179 lines
6.3 KiB
Lua
179 lines
6.3 KiB
Lua
--[[
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base64 -- v1.5.3 public domain Lua base64 encoder/decoder
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no warranty implied; use at your own risk
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author: Ilya Kolbin (iskolbin@gmail.com)
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url: github.com/iskolbin/lbase64
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LICENSE
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See end of file for license information.
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--]]
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local base64 = {}
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function extract( v, from, width )
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local w = 0
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local flag = 2^from
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for i = 0, width-1 do
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local flag2 = flag + flag
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if v % flag2 >= flag then
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w = w + 2^i
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end
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flag = flag2
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end
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return w
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end
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function base64.makeencoder( s62, s63, spad )
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local encoder = {}
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for b64code, char in pairs{[0]='A','B','C','D','E','F','G','H','I','J',
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'K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y',
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'Z','a','b','c','d','e','f','g','h','i','j','k','l','m','n',
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'o','p','q','r','s','t','u','v','w','x','y','z','0','1','2',
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'3','4','5','6','7','8','9',s62 or '+',s63 or'/',spad or'='} do
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encoder[b64code] = char:byte()
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end
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return encoder
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end
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function base64.makedecoder( s62, s63, spad )
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local decoder = {}
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for b64code, charcode in pairs( base64.makeencoder( s62, s63, spad )) do
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decoder[charcode] = b64code
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end
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return decoder
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end
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local DEFAULT_ENCODER = base64.makeencoder()
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local DEFAULT_DECODER = base64.makedecoder()
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local char, concat = string.char, table.concat
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function base64.encode( str, encoder, usecaching )
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encoder = encoder or DEFAULT_ENCODER
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local t, k, n = {}, 1, #str
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local lastn = n % 3
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local cache = {}
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for i = 1, n-lastn, 3 do
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local a, b, c = str:byte( i, i+2 )
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local v = a*0x10000 + b*0x100 + c
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local s
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if usecaching then
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s = cache[v]
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if not s then
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s = char(encoder[extract(v,18,6)], encoder[extract(v,12,6)], encoder[extract(v,6,6)], encoder[extract(v,0,6)])
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cache[v] = s
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end
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else
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s = char(encoder[extract(v,18,6)], encoder[extract(v,12,6)], encoder[extract(v,6,6)], encoder[extract(v,0,6)])
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end
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t[k] = s
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k = k + 1
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end
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if lastn == 2 then
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local a, b = str:byte( n-1, n )
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local v = a*0x10000 + b*0x100
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t[k] = char(encoder[extract(v,18,6)], encoder[extract(v,12,6)], encoder[extract(v,6,6)], encoder[64])
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elseif lastn == 1 then
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local v = str:byte( n )*0x10000
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t[k] = char(encoder[extract(v,18,6)], encoder[extract(v,12,6)], encoder[64], encoder[64])
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end
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return concat( t )
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end
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function base64.decode( b64, decoder, usecaching )
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decoder = decoder or DEFAULT_DECODER
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local pattern = '[^%w%+%/%=]'
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if decoder then
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local s62, s63
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for charcode, b64code in pairs( decoder ) do
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if b64code == 62 then s62 = charcode
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elseif b64code == 63 then s63 = charcode
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end
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end
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pattern = ('[^%%w%%%s%%%s%%=]'):format( char(s62), char(s63) )
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end
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b64 = b64:gsub( pattern, '' )
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local cache = usecaching and {}
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local t, k = {}, 1
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local n = #b64
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local padding = b64:sub(-2) == '==' and 2 or b64:sub(-1) == '=' and 1 or 0
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for i = 1, padding > 0 and n-4 or n, 4 do
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local a, b, c, d = b64:byte( i, i+3 )
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local s
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if usecaching then
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local v0 = a*0x1000000 + b*0x10000 + c*0x100 + d
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s = cache[v0]
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if not s then
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local v = decoder[a]*0x40000 + decoder[b]*0x1000 + decoder[c]*0x40 + decoder[d]
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s = char( extract(v,16,8), extract(v,8,8), extract(v,0,8))
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cache[v0] = s
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end
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else
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local v = decoder[a]*0x40000 + decoder[b]*0x1000 + decoder[c]*0x40 + decoder[d]
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s = char( extract(v,16,8), extract(v,8,8), extract(v,0,8))
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end
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t[k] = s
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k = k + 1
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end
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if padding == 1 then
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local a, b, c = b64:byte( n-3, n-1 )
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local v = decoder[a]*0x40000 + decoder[b]*0x1000 + decoder[c]*0x40
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t[k] = char( extract(v,16,8), extract(v,8,8))
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elseif padding == 2 then
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local a, b = b64:byte( n-3, n-2 )
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local v = decoder[a]*0x40000 + decoder[b]*0x1000
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t[k] = char( extract(v,16,8))
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end
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return concat( t )
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end
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return base64
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--[[
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------------------------------------------------------------------------------
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This software is available under 2 licenses -- choose whichever you prefer.
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------------------------------------------------------------------------------
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ALTERNATIVE A - MIT License
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Copyright (c) 2018 Ilya Kolbin
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Permission is hereby granted, free of charge, to any person obtaining a copy of
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this software and associated documentation files (the "Software"), to deal in
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the Software without restriction, including without limitation the rights to
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use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
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of the Software, and to permit persons to whom the Software is furnished to do
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so, subject to the following conditions:
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The above copyright notice and this permission notice shall be included in all
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copies or substantial portions of the Software.
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THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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SOFTWARE.
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------------------------------------------------------------------------------
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ALTERNATIVE B - Public Domain (www.unlicense.org)
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This is free and unencumbered software released into the public domain.
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Anyone is free to copy, modify, publish, use, compile, sell, or distribute this
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software, either in source code form or as a compiled binary, for any purpose,
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commercial or non-commercial, and by any means.
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In jurisdictions that recognize copyright laws, the author or authors of this
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software dedicate any and all copyright interest in the software to the public
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domain. We make this dedication for the benefit of the public at large and to
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the detriment of our heirs and successors. We intend this dedication to be an
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overt act of relinquishment in perpetuity of all present and future rights to
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this software under copyright law.
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THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
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ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
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WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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------------------------------------------------------------------------------
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--]]
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