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Created February 23, 2022 13:16
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LibDeflate (by Haoqian He/SafeteeWoW), pared down for ComputerCraft usage. Use `LibDeflate_min.lua` as LibDeflate to save space.
Raw
LibDeflate.lua
--[[--
LibDeflate 1.0.2-release <br>
Pure Lua compressor and decompressor with high compression ratio using
DEFLATE/zlib format.
Based on the original by Haoqian He, pared down for ComputerCraft usage
by Robert "khuxkm/minerobber" Miles
]] --[[
zlib License
(C) 2018-2021 Haoqian He
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely, subject to the following restrictions:
1. The origin of this software must not be misrepresented; you must not
claim that you wrote the original software. If you use this software
in a product, an acknowledgment in the product documentation would be
appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be
misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
License History:
1. GNU General Public License Version 3 in v1.0.0 and earlier versions.
2. GNU Lesser General Public License Version 3 in v1.0.1
3. the zlib License since v1.0.2
Credits and Disclaimer:
This library rewrites the code from the algorithm
and the ideas of the following projects,
and uses their code to help to test the correctness of this library,
but their code is not included directly in the library itself.
Their original licenses shall be comply when used.
1. zlib, by Jean-loup Gailly (compression) and Mark Adler (decompression).
http://www.zlib.net/
Licensed under zlib License. http://www.zlib.net/zlib_license.html
For the compression algorithm.
2. puff, by Mark Adler. https://github.com/madler/zlib/tree/master/contrib/puff
Licensed under zlib License. http://www.zlib.net/zlib_license.html
For the decompression algorithm.
3. LibCompress, by jjsheets and Galmok of European Stormrage (Horde)
https://www.wowace.com/projects/libcompress
Licensed under GPLv2.
https://www.gnu.org/licenses/old-licenses/gpl-2.0.html
For the code to create customized codec.
4. WeakAuras2,
https://github.com/WeakAuras/WeakAuras2
Licensed under GPLv2.
For the 6bit encoding and decoding.
]]
local LibDeflate
do
-- Semantic version. all lowercase.
-- Suffix can be alpha1, alpha2, beta1, beta2, rc1, rc2, etc.
-- NOTE: Two version numbers needs to modify.
-- 1. On the top of LibDeflate.lua
-- 2. _VERSION
-- 3. _MINOR
-- version to store the official version of LibDeflate
local _VERSION = "1.0.2-release"
local _COPYRIGHT = "LibDeflate " .. _VERSION ..
" Copyright (C) 2018-2021 Haoqian He." ..
" Modifications (c) 2022 minerobber"..
" Licensed under the zlib License"
LibDeflate = {}
LibDeflate._VERSION = _VERSION
LibDeflate._COPYRIGHT = _COPYRIGHT
end
-- localize Lua api for faster access.
local assert = assert
local error = error
local pairs = pairs
local string_byte = string.byte
local string_char = string.char
local string_find = string.find
local string_gsub = string.gsub
local string_sub = string.sub
local table_concat = table.concat
local table_sort = table.sort
local tostring = tostring
local type = type
-- Converts i to 2^i, (0<=i<=32)
-- This is used to implement bit left shift and bit right shift.
-- "x >> y" in C: "(x-x%_pow2[y])/_pow2[y]" in Lua
-- "x << y" in C: "x*_pow2[y]" in Lua
local _pow2 = {}
-- Converts any byte to a character, (0<=byte<=255)
local _byte_to_char = {}
-- _reverseBitsTbl[len][val] stores the bit reverse of
-- the number with bit length "len" and value "val"
-- For example, decimal number 6 with bits length 5 is binary 00110
-- It's reverse is binary 01100,
-- which is decimal 12 and 12 == _reverseBitsTbl[5][6]
-- 1<=len<=9, 0<=val<=2^len-1
-- The reason for 1<=len<=9 is that the max of min bitlen of huffman code
-- of a huffman alphabet is 9?
local _reverse_bits_tbl = {}
-- Convert a LZ77 length (3<=len<=258) to
-- a deflate literal/LZ77_length code (257<=code<=285)
local _length_to_deflate_code = {}
-- convert a LZ77 length (3<=len<=258) to
-- a deflate literal/LZ77_length code extra bits.
local _length_to_deflate_extra_bits = {}
-- Convert a LZ77 length (3<=len<=258) to
-- a deflate literal/LZ77_length code extra bit length.
local _length_to_deflate_extra_bitlen = {}
-- Convert a small LZ77 distance (1<=dist<=256) to a deflate code.
local _dist256_to_deflate_code = {}
-- Convert a small LZ77 distance (1<=dist<=256) to
-- a deflate distance code extra bits.
local _dist256_to_deflate_extra_bits = {}
-- Convert a small LZ77 distance (1<=dist<=256) to
-- a deflate distance code extra bit length.
local _dist256_to_deflate_extra_bitlen = {}
-- Convert a literal/LZ77_length deflate code to LZ77 base length
-- The key of the table is (code - 256), 257<=code<=285
local _literal_deflate_code_to_base_len =
{
3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31, 35, 43, 51, 59, 67,
83, 99, 115, 131, 163, 195, 227, 258
}
-- Convert a literal/LZ77_length deflate code to base LZ77 length extra bits
-- The key of the table is (code - 256), 257<=code<=285
local _literal_deflate_code_to_extra_bitlen =
{
0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 5,
5, 5, 5, 0
}
-- Convert a distance deflate code to base LZ77 distance. (0<=code<=29)
local _dist_deflate_code_to_base_dist = {
[0] = 1,
2,
3,
4,
5,
7,
9,
13,
17,
25,
33,
49,
65,
97,
129,
193,
257,
385,
513,
769,
1025,
1537,
2049,
3073,
4097,
6145,
8193,
12289,
16385,
24577
}
-- Convert a distance deflate code to LZ77 bits length. (0<=code<=29)
local _dist_deflate_code_to_extra_bitlen =
{
[0] = 0,
0,
0,
0,
1,
1,
2,
2,
3,
3,
4,
4,
5,
5,
6,
6,
7,
7,
8,
8,
9,
9,
10,
10,
11,
11,
12,
12,
13,
13
}
-- The code order of the first huffman header in the dynamic deflate block.
-- See the page 12 of RFC1951
local _rle_codes_huffman_bitlen_order = {
16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15
}
-- The following tables are used by fixed deflate block.
-- The value of these tables are assigned at the bottom of the source.
-- The huffman code of the literal/LZ77_length deflate codes,
-- in fixed deflate block.
local _fix_block_literal_huffman_code
-- Convert huffman code of the literal/LZ77_length to deflate codes,
-- in fixed deflate block.
local _fix_block_literal_huffman_to_deflate_code
-- The bit length of the huffman code of literal/LZ77_length deflate codes,
-- in fixed deflate block.
local _fix_block_literal_huffman_bitlen
-- The count of each bit length of the literal/LZ77_length deflate codes,
-- in fixed deflate block.
local _fix_block_literal_huffman_bitlen_count
-- The huffman code of the distance deflate codes,
-- in fixed deflate block.
local _fix_block_dist_huffman_code
-- Convert huffman code of the distance to deflate codes,
-- in fixed deflate block.
local _fix_block_dist_huffman_to_deflate_code
-- The bit length of the huffman code of the distance deflate codes,
-- in fixed deflate block.
local _fix_block_dist_huffman_bitlen
-- The count of each bit length of the huffman code of
-- the distance deflate codes,
-- in fixed deflate block.
local _fix_block_dist_huffman_bitlen_count
for i = 0, 255 do _byte_to_char[i] = string_char(i) end
do
local pow = 1
for i = 0, 32 do
_pow2[i] = pow
pow = pow * 2
end
end
for i = 1, 9 do
_reverse_bits_tbl[i] = {}
for j = 0, _pow2[i + 1] - 1 do
local reverse = 0
local value = j
for _ = 1, i do
-- The following line is equivalent to "res | (code %2)" in C.
reverse = reverse - reverse % 2 +
(((reverse % 2 == 1) or (value % 2) == 1) and 1 or 0)
value = (value - value % 2) / 2
reverse = reverse * 2
end
_reverse_bits_tbl[i][j] = (reverse - reverse % 2) / 2
end
end
-- The source code is written according to the pattern in the numbers
-- in RFC1951 Page10.
do
local a = 18
local b = 16
local c = 265
local bitlen = 1
for len = 3, 258 do
if len <= 10 then
_length_to_deflate_code[len] = len + 254
_length_to_deflate_extra_bitlen[len] = 0
elseif len == 258 then
_length_to_deflate_code[len] = 285
_length_to_deflate_extra_bitlen[len] = 0
else
if len > a then
a = a + b
b = b * 2
c = c + 4
bitlen = bitlen + 1
end
local t = len - a - 1 + b / 2
_length_to_deflate_code[len] = (t - (t % (b / 8))) / (b / 8) + c
_length_to_deflate_extra_bitlen[len] = bitlen
_length_to_deflate_extra_bits[len] = t % (b / 8)
end
end
end
-- The source code is written according to the pattern in the numbers
-- in RFC1951 Page11.
do
_dist256_to_deflate_code[1] = 0
_dist256_to_deflate_code[2] = 1
_dist256_to_deflate_extra_bitlen[1] = 0
_dist256_to_deflate_extra_bitlen[2] = 0
local a = 3
local b = 4
local code = 2
local bitlen = 0
for dist = 3, 256 do
if dist > b then
a = a * 2
b = b * 2
code = code + 2
bitlen = bitlen + 1
end
_dist256_to_deflate_code[dist] = (dist <= a) and code or (code + 1)
_dist256_to_deflate_extra_bitlen[dist] = (bitlen < 0) and 0 or bitlen
if b >= 8 then
_dist256_to_deflate_extra_bits[dist] = (dist - b / 2 - 1) % (b / 4)
end
end
end
--- Calculate the Adler-32 checksum of the string. <br>
-- See RFC1950 Page 9 https://tools.ietf.org/html/rfc1950 for the
-- definition of Adler-32 checksum.
-- @param str [string] the input string to calcuate its Adler-32 checksum.
-- @return [integer] The Adler-32 checksum, which is greater or equal to 0,
-- and less than 2^32 (4294967296).
function LibDeflate:Adler32(str)
-- This function is loop unrolled by better performance.
--
-- Here is the minimum code:
--
-- local a = 1
-- local b = 0
-- for i=1, #str do
-- local s = string.byte(str, i, i)
-- a = (a+s)%65521
-- b = (b+a)%65521
-- end
-- return b*65536+a
if type(str) ~= "string" then
error(("Usage: LibDeflate:Adler32(str):" ..
" 'str' - string expected got '%s'."):format(type(str)), 2)
end
local strlen = #str
local i = 1
local a = 1
local b = 0
while i <= strlen - 15 do
local x1, x2, x3, x4, x5, x6, x7, x8, x9, x10, x11, x12, x13, x14, x15, x16 =
string_byte(str, i, i + 15)
b =
(b + 16 * a + 16 * x1 + 15 * x2 + 14 * x3 + 13 * x4 + 12 * x5 + 11 * x6 +
10 * x7 + 9 * x8 + 8 * x9 + 7 * x10 + 6 * x11 + 5 * x12 + 4 * x13 + 3 *
x14 + 2 * x15 + x16) % 65521
a =
(a + x1 + x2 + x3 + x4 + x5 + x6 + x7 + x8 + x9 + x10 + x11 + x12 + x13 +
x14 + x15 + x16) % 65521
i = i + 16
end
while (i <= strlen) do
local x = string_byte(str, i, i)
a = (a + x) % 65521
b = (b + a) % 65521
i = i + 1
end
return (b * 65536 + a) % 4294967296
end
-- Compare adler32 checksum.
-- adler32 should be compared with a mod to avoid sign problem
-- 4072834167 (unsigned) is the same adler32 as -222133129
local function IsEqualAdler32(actual, expected)
return (actual % 4294967296) == (expected % 4294967296)
end
--- Create a preset dictionary.
--
-- This function is not fast, and the memory consumption of the produced
-- dictionary is about 50 times of the input string. Therefore, it is suggestted
-- to run this function only once in your program.
--
-- It is very important to know that if you do use a preset dictionary,
-- compressors and decompressors MUST USE THE SAME dictionary. That is,
-- dictionary must be created using the same string. If you update your program
-- with a new dictionary, people with the old version won't be able to transmit
-- data with people with the new version. Therefore, changing the dictionary
-- must be very careful.
--
-- The parameters "strlen" and "adler32" add a layer of verification to ensure
-- the parameter "str" is not modified unintentionally during the program
-- development.
--
-- @usage local dict_str = "1234567890"
--
-- -- print(dict_str:len(), LibDeflate:Adler32(dict_str))
-- -- Hardcode the print result below to verify it to avoid acciently
-- -- modification of 'str' during the program development.
-- -- string length: 10, Adler-32: 187433486,
-- -- Don't calculate string length and its Adler-32 at run-time.
--
-- local dict = LibDeflate:CreateDictionary(dict_str, 10, 187433486)
--
-- @param str [string] The string used as the preset dictionary. <br>
-- You should put stuffs that frequently appears in the dictionary
-- string and preferablely put more frequently appeared stuffs toward the end
-- of the string. <br>
-- Empty string and string longer than 32768 bytes are not allowed.
-- @param strlen [integer] The length of 'str'. Please pass in this parameter
-- as a hardcoded constant, in order to verify the content of 'str'. The value
-- of this parameter should be known before your program runs.
-- @param adler32 [integer] The Adler-32 checksum of 'str'. Please pass in this
-- parameter as a hardcoded constant, in order to verify the content of 'str'.
-- The value of this parameter should be known before your program runs.
-- @return [table] The dictionary used for preset dictionary compression and
-- decompression.
-- @raise error if 'strlen' does not match the length of 'str',
-- or if 'adler32' does not match the Adler-32 checksum of 'str'.
function LibDeflate:CreateDictionary(str, strlen, adler32)
if type(str) ~= "string" then
error(("Usage: LibDeflate:CreateDictionary(str, strlen, adler32):" ..
" 'str' - string expected got '%s'."):format(type(str)), 2)
end
if type(strlen) ~= "number" then
error(("Usage: LibDeflate:CreateDictionary(str, strlen, adler32):" ..
" 'strlen' - number expected got '%s'."):format(type(strlen)), 2)
end
if type(adler32) ~= "number" then
error(("Usage: LibDeflate:CreateDictionary(str, strlen, adler32):" ..
" 'adler32' - number expected got '%s'."):format(type(adler32)), 2)
end
if strlen ~= #str then
error(("Usage: LibDeflate:CreateDictionary(str, strlen, adler32):" ..
" 'strlen' does not match the actual length of 'str'." ..
" 'strlen': %u, '#str': %u ." ..
" Please check if 'str' is modified unintentionally."):format(
strlen, #str))
end
if strlen == 0 then
error(("Usage: LibDeflate:CreateDictionary(str, strlen, adler32):" ..
" 'str' - Empty string is not allowed."), 2)
end
if strlen > 32768 then
error(("Usage: LibDeflate:CreateDictionary(str, strlen, adler32):" ..
" 'str' - string longer than 32768 bytes is not allowed." ..
" Got %d bytes."):format(strlen), 2)
end
local actual_adler32 = self:Adler32(str)
if not IsEqualAdler32(adler32, actual_adler32) then
error(("Usage: LibDeflate:CreateDictionary(str, strlen, adler32):" ..
" 'adler32' does not match the actual adler32 of 'str'." ..
" 'adler32': %u, 'Adler32(str)': %u ." ..
" Please check if 'str' is modified unintentionally."):format(
adler32, actual_adler32))
end
local dictionary = {}
dictionary.adler32 = adler32
dictionary.hash_tables = {}
dictionary.string_table = {}
dictionary.strlen = strlen
local string_table = dictionary.string_table
local hash_tables = dictionary.hash_tables
string_table[1] = string_byte(str, 1, 1)
string_table[2] = string_byte(str, 2, 2)
if strlen >= 3 then
local i = 1
local hash = string_table[1] * 256 + string_table[2]
while i <= strlen - 2 - 3 do
local x1, x2, x3, x4 = string_byte(str, i + 2, i + 5)
string_table[i + 2] = x1
string_table[i + 3] = x2
string_table[i + 4] = x3
string_table[i + 5] = x4
hash = (hash * 256 + x1) % 16777216
local t = hash_tables[hash]
if not t then
t = {};
hash_tables[hash] = t
end
t[#t + 1] = i - strlen
i = i + 1
hash = (hash * 256 + x2) % 16777216
t = hash_tables[hash]
if not t then
t = {};
hash_tables[hash] = t
end
t[#t + 1] = i - strlen
i = i + 1
hash = (hash * 256 + x3) % 16777216
t = hash_tables[hash]
if not t then
t = {};
hash_tables[hash] = t
end
t[#t + 1] = i - strlen
i = i + 1
hash = (hash * 256 + x4) % 16777216
t = hash_tables[hash]
if not t then
t = {};
hash_tables[hash] = t
end
t[#t + 1] = i - strlen
i = i + 1
end
while i <= strlen - 2 do
local x = string_byte(str, i + 2)
string_table[i + 2] = x
hash = (hash * 256 + x) % 16777216
local t = hash_tables[hash]
if not t then
t = {};
hash_tables[hash] = t
end
t[#t + 1] = i - strlen
i = i + 1
end
end
return dictionary
end
-- Check if the dictionary is valid.
-- @param dictionary The preset dictionary for compression and decompression.
-- @return true if valid, false if not valid.
-- @return if not valid, the error message.
local function IsValidDictionary(dictionary)
if type(dictionary) ~= "table" then
return false,
("'dictionary' - table expected got '%s'."):format(type(dictionary))
end
if type(dictionary.adler32) ~= "number" or type(dictionary.string_table) ~=
"table" or type(dictionary.strlen) ~= "number" or dictionary.strlen <= 0 or
dictionary.strlen > 32768 or dictionary.strlen ~= #dictionary.string_table or
type(dictionary.hash_tables) ~= "table" then
return false,
("'dictionary' - corrupted dictionary."):format(type(dictionary))
end
return true, ""
end
--[[
key of the configuration table is the compression level,
and its value stores the compression setting.
These numbers come from zlib source code.
Higher compression level usually means better compression.
(Because LibDeflate uses a simplified version of zlib algorithm,
there is no guarantee that higher compression level does not create
bigger file than lower level, but I can say it's 99% likely)
Be careful with the high compression level. This is a pure lua
implementation compressor/decompressor, which is significant slower than
a C/C++ equivalant compressor/decompressor. Very high compression level
costs significant more CPU time, and usually compression size won't be
significant smaller when you increase compression level by 1, when the
level is already very high. Benchmark yourself if you can afford it.
See also https://github.com/madler/zlib/blob/master/doc/algorithm.txt,
https://github.com/madler/zlib/blob/master/deflate.c for more information.
The meaning of each field:
@field 1 use_lazy_evaluation:
true/false. Whether the program uses lazy evaluation.
See what is "lazy evaluation" in the link above.
lazy_evaluation improves ratio, but relatively slow.
@field 2 good_prev_length:
Only effective if lazy is set, Only use 1/4 of max_chain,
if prev length of lazy match is above this.
@field 3 max_insert_length/max_lazy_match:
If not using lazy evaluation,
insert new strings in the hash table only if the match length is not
greater than this length.
If using lazy evaluation, only continue lazy evaluation,
if previous match length is strictly smaller than this value.
@field 4 nice_length:
Number. Don't continue to go down the hash chain,
if match length is above this.
@field 5 max_chain:
Number. The maximum number of hash chains we look.
--]]
local _compression_level_configs = {
[0] = {false, nil, 0, 0, 0}, -- level 0, no compression
[1] = {false, nil, 4, 8, 4}, -- level 1, similar to zlib level 1
[2] = {false, nil, 5, 18, 8}, -- level 2, similar to zlib level 2
[3] = {false, nil, 6, 32, 32}, -- level 3, similar to zlib level 3
[4] = {true, 4, 4, 16, 16}, -- level 4, similar to zlib level 4
[5] = {true, 8, 16, 32, 32}, -- level 5, similar to zlib level 5
[6] = {true, 8, 16, 128, 128}, -- level 6, similar to zlib level 6
[7] = {true, 8, 32, 128, 256}, -- (SLOW) level 7, similar to zlib level 7
[8] = {true, 32, 128, 258, 1024}, -- (SLOW) level 8,similar to zlib level 8
[9] = {true, 32, 258, 258, 4096}
-- (VERY SLOW) level 9, similar to zlib level 9
}
-- Check if the compression/decompression arguments is valid
-- @param str The input string.
-- @param check_dictionary if true, check if dictionary is valid.
-- @param dictionary The preset dictionary for compression and decompression.
-- @param check_configs if true, check if config is valid.
-- @param configs The compression configuration table
-- @return true if valid, false if not valid.
-- @return if not valid, the error message.
local function IsValidArguments(str, check_dictionary, dictionary,
check_configs, configs)
if type(str) ~= "string" then
return false, ("'str' - string expected got '%s'."):format(type(str))
end
if check_dictionary then
local dict_valid, dict_err = IsValidDictionary(dictionary)
if not dict_valid then return false, dict_err end
end
if check_configs then
local type_configs = type(configs)
if type_configs ~= "nil" and type_configs ~= "table" then
return false, ("'configs' - nil or table expected got '%s'."):format(
type(configs))
end
if type_configs == "table" then
for k, v in pairs(configs) do
if k ~= "level" and k ~= "strategy" then
return false,
("'configs' - unsupported table key in the configs: '%s'."):format(
k)
elseif k == "level" and not _compression_level_configs[v] then
return false,
("'configs' - unsupported 'level': %s."):format(tostring(v))
elseif k == "strategy" and v ~= "fixed" and v ~= "huffman_only" and v ~=
"dynamic" then
-- random_block_type is for testing purpose
return false, ("'configs' - unsupported 'strategy': '%s'."):format(
tostring(v))
end
end
end
end
return true, ""
end
--[[ --------------------------------------------------------------------------
Compress code
--]] --------------------------------------------------------------------------
-- partial flush to save memory
local _FLUSH_MODE_MEMORY_CLEANUP = 0
-- full flush with partial bytes
local _FLUSH_MODE_OUTPUT = 1
-- write bytes to get to byte boundary
local _FLUSH_MODE_BYTE_BOUNDARY = 2
-- no flush, just get num of bits written so far
local _FLUSH_MODE_NO_FLUSH = 3
--[[
Create an empty writer to easily write stuffs as the unit of bits.
Return values:
1. WriteBits(code, bitlen):
2. WriteString(str):
3. Flush(mode):
--]]
local function CreateWriter()
local buffer_size = 0
local cache = 0
local cache_bitlen = 0
local total_bitlen = 0
local buffer = {}
-- When buffer is big enough, flush into result_buffer to save memory.
local result_buffer = {}
-- Write bits with value "value" and bit length of "bitlen" into writer.
-- @param value: The value being written
-- @param bitlen: The bit length of "value"
-- @return nil
local function WriteBits(value, bitlen)
cache = cache + value * _pow2[cache_bitlen]
cache_bitlen = cache_bitlen + bitlen
total_bitlen = total_bitlen + bitlen
-- Only bulk to buffer every 4 bytes. This is quicker.
if cache_bitlen >= 32 then
buffer_size = buffer_size + 1
buffer[buffer_size] = _byte_to_char[cache % 256] ..
_byte_to_char[((cache - cache % 256) / 256 % 256)] ..
_byte_to_char[((cache - cache % 65536) / 65536 %
256)] ..
_byte_to_char[((cache - cache % 16777216) /
16777216 % 256)]
local rshift_mask = _pow2[32 - cache_bitlen + bitlen]
cache = (value - value % rshift_mask) / rshift_mask
cache_bitlen = cache_bitlen - 32
end
end
-- Write the entire string into the writer.
-- @param str The string being written
-- @return nil
local function WriteString(str)
for _ = 1, cache_bitlen, 8 do
buffer_size = buffer_size + 1
buffer[buffer_size] = string_char(cache % 256)
cache = (cache - cache % 256) / 256
end
cache_bitlen = 0
buffer_size = buffer_size + 1
buffer[buffer_size] = str
total_bitlen = total_bitlen + #str * 8
end
-- Flush current stuffs in the writer and return it.
-- This operation will free most of the memory.
-- @param mode See the descrtion of the constant and the source code.
-- @return The total number of bits stored in the writer right now.
-- for byte boundary mode, it includes the padding bits.
-- for output mode, it does not include padding bits.
-- @return Return the outputs if mode is output.
local function FlushWriter(mode)
if mode == _FLUSH_MODE_NO_FLUSH then return total_bitlen end
if mode == _FLUSH_MODE_OUTPUT or mode == _FLUSH_MODE_BYTE_BOUNDARY then
-- Full flush, also output cache.
-- Need to pad some bits if cache_bitlen is not multiple of 8.
local padding_bitlen = (8 - cache_bitlen % 8) % 8
if cache_bitlen > 0 then
-- padding with all 1 bits, mainly because "\000" is not
-- good to be tranmitted. I do this so "\000" is a little bit
-- less frequent.
cache = cache - _pow2[cache_bitlen] +
_pow2[cache_bitlen + padding_bitlen]
for _ = 1, cache_bitlen, 8 do
buffer_size = buffer_size + 1
buffer[buffer_size] = _byte_to_char[cache % 256]
cache = (cache - cache % 256) / 256
end
cache = 0
cache_bitlen = 0
end
if mode == _FLUSH_MODE_BYTE_BOUNDARY then
total_bitlen = total_bitlen + padding_bitlen
return total_bitlen
end
end
local flushed = table_concat(buffer)
buffer = {}
buffer_size = 0
result_buffer[#result_buffer + 1] = flushed
if mode == _FLUSH_MODE_MEMORY_CLEANUP then
return total_bitlen
else
return total_bitlen, table_concat(result_buffer)
end
end
return WriteBits, WriteString, FlushWriter
end
-- Push an element into a max heap
-- @param heap A max heap whose max element is at index 1.
-- @param e The element to be pushed. Assume element "e" is a table
-- and comparison is done via its first entry e[1]
-- @param heap_size current number of elements in the heap.
-- NOTE: There may be some garbage stored in
-- heap[heap_size+1], heap[heap_size+2], etc..
-- @return nil
local function MinHeapPush(heap, e, heap_size)
heap_size = heap_size + 1
heap[heap_size] = e
local value = e[1]
local pos = heap_size
local parent_pos = (pos - pos % 2) / 2
while (parent_pos >= 1 and heap[parent_pos][1] > value) do
local t = heap[parent_pos]
heap[parent_pos] = e
heap[pos] = t
pos = parent_pos
parent_pos = (parent_pos - parent_pos % 2) / 2
end
end
-- Pop an element from a max heap
-- @param heap A max heap whose max element is at index 1.
-- @param heap_size current number of elements in the heap.
-- @return the poped element
-- Note: This function does not change table size of "heap" to save CPU time.
local function MinHeapPop(heap, heap_size)
local top = heap[1]
local e = heap[heap_size]
local value = e[1]
heap[1] = e
heap[heap_size] = top
heap_size = heap_size - 1
local pos = 1
local left_child_pos = pos * 2
local right_child_pos = left_child_pos + 1
while (left_child_pos <= heap_size) do
local left_child = heap[left_child_pos]
if (right_child_pos <= heap_size and heap[right_child_pos][1] <
left_child[1]) then
local right_child = heap[right_child_pos]
if right_child[1] < value then
heap[right_child_pos] = e
heap[pos] = right_child
pos = right_child_pos
left_child_pos = pos * 2
right_child_pos = left_child_pos + 1
else
break
end
else
if left_child[1] < value then
heap[left_child_pos] = e
heap[pos] = left_child
pos = left_child_pos
left_child_pos = pos * 2
right_child_pos = left_child_pos + 1
else
break
end
end
end
return top
end
-- Deflate defines a special huffman tree, which is unique once the bit length
-- of huffman code of all symbols are known.
-- @param bitlen_count Number of symbols with a specific bitlen
-- @param symbol_bitlen The bit length of a symbol
-- @param max_symbol The max symbol among all symbols,
-- which is (number of symbols - 1)
-- @param max_bitlen The max huffman bit length among all symbols.
-- @return The huffman code of all symbols.
local function GetHuffmanCodeFromBitlen(bitlen_counts, symbol_bitlens,
max_symbol, max_bitlen)
local huffman_code = 0
local next_codes = {}
local symbol_huffman_codes = {}
for bitlen = 1, max_bitlen do
huffman_code = (huffman_code + (bitlen_counts[bitlen - 1] or 0)) * 2
next_codes[bitlen] = huffman_code
end
for symbol = 0, max_symbol do
local bitlen = symbol_bitlens[symbol]
if bitlen then
huffman_code = next_codes[bitlen]
next_codes[bitlen] = huffman_code + 1
-- Reverse the bits of huffman code,
-- because most signifant bits of huffman code
-- is stored first into the compressed data.
-- @see RFC1951 Page5 Section 3.1.1
if bitlen <= 9 then -- Have cached reverse for small bitlen.
symbol_huffman_codes[symbol] = _reverse_bits_tbl[bitlen][huffman_code]
else
local reverse = 0
for _ = 1, bitlen do
reverse = reverse - reverse % 2 +
(((reverse % 2 == 1) or (huffman_code % 2) == 1) and 1 or
0)
huffman_code = (huffman_code - huffman_code % 2) / 2
reverse = reverse * 2
end
symbol_huffman_codes[symbol] = (reverse - reverse % 2) / 2
end
end
end
return symbol_huffman_codes
end
-- A helper function to sort heap elements
-- a[1], b[1] is the huffman frequency
-- a[2], b[2] is the symbol value.
local function SortByFirstThenSecond(a, b)
return a[1] < b[1] or (a[1] == b[1] and a[2] < b[2])
end
-- Calculate the huffman bit length and huffman code.
-- @param symbol_count: A table whose table key is the symbol, and table value
-- is the symbol frenquency (nil means 0 frequency).
-- @param max_bitlen: See description of return value.
-- @param max_symbol: The maximum symbol
-- @return a table whose key is the symbol, and the value is the huffman bit
-- bit length. We guarantee that all bit length <= max_bitlen.
-- For 0<=symbol<=max_symbol, table value could be nil if the frequency
-- of the symbol is 0 or nil.
-- @return a table whose key is the symbol, and the value is the huffman code.
-- @return a number indicating the maximum symbol whose bitlen is not 0.
local function GetHuffmanBitlenAndCode(symbol_counts, max_bitlen, max_symbol)
local heap_size
local max_non_zero_bitlen_symbol = -1
local leafs = {}
local heap = {}
local symbol_bitlens = {}
local symbol_codes = {}
local bitlen_counts = {}
--[[
tree[1]: weight, temporarily used as parent and bitLengths
tree[2]: symbol
tree[3]: left child
tree[4]: right child
--]]
local number_unique_symbols = 0
for symbol, count in pairs(symbol_counts) do
number_unique_symbols = number_unique_symbols + 1
leafs[number_unique_symbols] = {count, symbol}
end
if (number_unique_symbols == 0) then
-- no code.
return {}, {}, -1
elseif (number_unique_symbols == 1) then
-- Only one code. In this case, its huffman code
-- needs to be assigned as 0, and bit length is 1.
-- This is the only case that the return result
-- represents an imcomplete huffman tree.
local symbol = leafs[1][2]
symbol_bitlens[symbol] = 1
symbol_codes[symbol] = 0
return symbol_bitlens, symbol_codes, symbol
else
table_sort(leafs, SortByFirstThenSecond)
heap_size = number_unique_symbols
for i = 1, heap_size do heap[i] = leafs[i] end
while (heap_size > 1) do
-- Note: pop does not change table size of heap
local leftChild = MinHeapPop(heap, heap_size)
heap_size = heap_size - 1
local rightChild = MinHeapPop(heap, heap_size)
heap_size = heap_size - 1
local newNode = {leftChild[1] + rightChild[1], -1, leftChild, rightChild}
MinHeapPush(heap, newNode, heap_size)
heap_size = heap_size + 1
end
-- Number of leafs whose bit length is greater than max_len.
local number_bitlen_overflow = 0
-- Calculate bit length of all nodes
local fifo = {heap[1], 0, 0, 0} -- preallocate some spaces.
local fifo_size = 1
local index = 1
heap[1][1] = 0
while (index <= fifo_size) do -- Breath first search
local e = fifo[index]
local bitlen = e[1]
local symbol = e[2]
local left_child = e[3]
local right_child = e[4]
if left_child then
fifo_size = fifo_size + 1
fifo[fifo_size] = left_child
left_child[1] = bitlen + 1
end
if right_child then
fifo_size = fifo_size + 1
fifo[fifo_size] = right_child
right_child[1] = bitlen + 1
end
index = index + 1
if (bitlen > max_bitlen) then
number_bitlen_overflow = number_bitlen_overflow + 1
bitlen = max_bitlen
end
if symbol >= 0 then
symbol_bitlens[symbol] = bitlen
max_non_zero_bitlen_symbol = (symbol > max_non_zero_bitlen_symbol) and
symbol or max_non_zero_bitlen_symbol
bitlen_counts[bitlen] = (bitlen_counts[bitlen] or 0) + 1
end
end
-- Resolve bit length overflow
-- @see ZLib/trees.c:gen_bitlen(s, desc), for reference
if (number_bitlen_overflow > 0) then
repeat
local bitlen = max_bitlen - 1
while ((bitlen_counts[bitlen] or 0) == 0) do bitlen = bitlen - 1 end
-- move one leaf down the tree
bitlen_counts[bitlen] = bitlen_counts[bitlen] - 1
-- move one overflow item as its brother
bitlen_counts[bitlen + 1] = (bitlen_counts[bitlen + 1] or 0) + 2
bitlen_counts[max_bitlen] = bitlen_counts[max_bitlen] - 1
number_bitlen_overflow = number_bitlen_overflow - 2
until (number_bitlen_overflow <= 0)
index = 1
for bitlen = max_bitlen, 1, -1 do
local n = bitlen_counts[bitlen] or 0
while (n > 0) do
local symbol = leafs[index][2]
symbol_bitlens[symbol] = bitlen
n = n - 1
index = index + 1
end
end
end
symbol_codes = GetHuffmanCodeFromBitlen(bitlen_counts, symbol_bitlens,
max_symbol, max_bitlen)
return symbol_bitlens, symbol_codes, max_non_zero_bitlen_symbol
end
end
-- Calculate the first huffman header in the dynamic huffman block
-- @see RFC1951 Page 12
-- @param lcode_bitlen: The huffman bit length of literal/LZ77_length.
-- @param max_non_zero_bitlen_lcode: The maximum literal/LZ77_length symbol
-- whose huffman bit length is not zero.
-- @param dcode_bitlen: The huffman bit length of LZ77 distance.
-- @param max_non_zero_bitlen_dcode: The maximum LZ77 distance symbol
-- whose huffman bit length is not zero.
-- @return The run length encoded codes.
-- @return The extra bits. One entry for each rle code that needs extra bits.
-- (code == 16 or 17 or 18).
-- @return The count of appearance of each rle codes.
local function RunLengthEncodeHuffmanBitlen(lcode_bitlens,
max_non_zero_bitlen_lcode,
dcode_bitlens,
max_non_zero_bitlen_dcode)
local rle_code_tblsize = 0
local rle_codes = {}
local rle_code_counts = {}
local rle_extra_bits_tblsize = 0
local rle_extra_bits = {}
local prev = nil
local count = 0
-- If there is no distance code, assume one distance code of bit length 0.
-- RFC1951: One distance code of zero bits means that
-- there are no distance codes used at all (the data is all literals).
max_non_zero_bitlen_dcode = (max_non_zero_bitlen_dcode < 0) and 0 or
max_non_zero_bitlen_dcode
local max_code = max_non_zero_bitlen_lcode + max_non_zero_bitlen_dcode + 1
for code = 0, max_code + 1 do
local len = (code <= max_non_zero_bitlen_lcode) and
(lcode_bitlens[code] or 0) or ((code <= max_code) and
(dcode_bitlens[code - max_non_zero_bitlen_lcode - 1] or 0) or
nil)
if len == prev then
count = count + 1
if len ~= 0 and count == 6 then
rle_code_tblsize = rle_code_tblsize + 1
rle_codes[rle_code_tblsize] = 16
rle_extra_bits_tblsize = rle_extra_bits_tblsize + 1
rle_extra_bits[rle_extra_bits_tblsize] = 3
rle_code_counts[16] = (rle_code_counts[16] or 0) + 1
count = 0
elseif len == 0 and count == 138 then
rle_code_tblsize = rle_code_tblsize + 1
rle_codes[rle_code_tblsize] = 18
rle_extra_bits_tblsize = rle_extra_bits_tblsize + 1
rle_extra_bits[rle_extra_bits_tblsize] = 127
rle_code_counts[18] = (rle_code_counts[18] or 0) + 1
count = 0
end
else
if count == 1 then
rle_code_tblsize = rle_code_tblsize + 1
rle_codes[rle_code_tblsize] = prev
rle_code_counts[prev] = (rle_code_counts[prev] or 0) + 1
elseif count == 2 then
rle_code_tblsize = rle_code_tblsize + 1
rle_codes[rle_code_tblsize] = prev
rle_code_tblsize = rle_code_tblsize + 1
rle_codes[rle_code_tblsize] = prev
rle_code_counts[prev] = (rle_code_counts[prev] or 0) + 2
elseif count >= 3 then
rle_code_tblsize = rle_code_tblsize + 1
local rleCode = (prev ~= 0) and 16 or (count <= 10 and 17 or 18)
rle_codes[rle_code_tblsize] = rleCode
rle_code_counts[rleCode] = (rle_code_counts[rleCode] or 0) + 1
rle_extra_bits_tblsize = rle_extra_bits_tblsize + 1
rle_extra_bits[rle_extra_bits_tblsize] =
(count <= 10) and (count - 3) or (count - 11)
end
prev = len
if len and len ~= 0 then
rle_code_tblsize = rle_code_tblsize + 1
rle_codes[rle_code_tblsize] = len
rle_code_counts[len] = (rle_code_counts[len] or 0) + 1
count = 0
else
count = 1
end
end
end
return rle_codes, rle_extra_bits, rle_code_counts
end
-- Load the string into a table, in order to speed up LZ77.
-- Loop unrolled 16 times to speed this function up.
-- @param str The string to be loaded.
-- @param t The load destination
-- @param start str[index] will be the first character to be loaded.
-- @param end str[index] will be the last character to be loaded
-- @param offset str[index] will be loaded into t[index-offset]
-- @return t
local function LoadStringToTable(str, t, start, stop, offset)
local i = start - offset
while i <= stop - 15 - offset do
t[i], t[i + 1], t[i + 2], t[i + 3], t[i + 4], t[i + 5], t[i + 6], t[i + 7], t[i +
8], t[i + 9], t[i + 10], t[i + 11], t[i + 12], t[i + 13], t[i + 14], t[i +
15] = string_byte(str, i + offset, i + 15 + offset)
i = i + 16
end
while (i <= stop - offset) do
t[i] = string_byte(str, i + offset, i + offset)
i = i + 1
end
return t
end
-- Do LZ77 process. This function uses the majority of the CPU time.
-- @see zlib/deflate.c:deflate_fast(), zlib/deflate.c:deflate_slow()
-- @see https://github.com/madler/zlib/blob/master/doc/algorithm.txt
-- This function uses the algorithms used above. You should read the
-- algorithm.txt above to understand what is the hash function and the
-- lazy evaluation.
--
-- The special optimization used here is hash functions used here.
-- The hash function is just the multiplication of the three consective
-- characters. So if the hash matches, it guarantees 3 characters are matched.
-- This optimization can be implemented because Lua table is a hash table.
--
-- @param level integer that describes compression level.
-- @param string_table table that stores the value of string to be compressed.
-- The index of this table starts from 1.
-- The caller needs to make sure all values needed by this function
-- are loaded.
-- Assume "str" is the origin input string into the compressor
-- str[block_start]..str[block_end+3] needs to be loaded into
-- string_table[block_start-offset]..string_table[block_end-offset]
-- If dictionary is presented, the last 258 bytes of the dictionary
-- needs to be loaded into sing_table[-257..0]
-- (See more in the description of offset.)
-- @param hash_tables. The table key is the hash value (0<=hash<=16777216=256^3)
-- The table value is an array0 that stores the indexes of the
-- input data string to be compressed, such that
-- hash == str[index]*str[index+1]*str[index+2]
-- Indexes are ordered in this array.
-- @param block_start The indexes of the input data string to be compressed.
-- that starts the LZ77 block.
-- @param block_end The indexes of the input data string to be compressed.
-- that stores the LZ77 block.
-- @param offset str[index] is stored in string_table[index-offset],
-- This offset is mainly an optimization to limit the index
-- of string_table, so lua can access this table quicker.
-- @param dictionary See LibDeflate:CreateDictionary
-- @return literal/LZ77_length deflate codes.
-- @return the extra bits of literal/LZ77_length deflate codes.
-- @return the count of each literal/LZ77 deflate code.
-- @return LZ77 distance deflate codes.
-- @return the extra bits of LZ77 distance deflate codes.
-- @return the count of each LZ77 distance deflate code.
local function GetBlockLZ77Result(level, string_table, hash_tables, block_start,
block_end, offset, dictionary)
local config = _compression_level_configs[level]
local config_use_lazy, config_good_prev_length, config_max_lazy_match,
config_nice_length, config_max_hash_chain = config[1], config[2],
config[3], config[4],
config[5]
local config_max_insert_length = (not config_use_lazy) and
config_max_lazy_match or 2147483646
local config_good_hash_chain =
(config_max_hash_chain - config_max_hash_chain % 4 / 4)
local hash
local dict_hash_tables
local dict_string_table
local dict_string_len = 0
if dictionary then
dict_hash_tables = dictionary.hash_tables
dict_string_table = dictionary.string_table
dict_string_len = dictionary.strlen
assert(block_start == 1)
if block_end >= block_start and dict_string_len >= 2 then
hash = dict_string_table[dict_string_len - 1] * 65536 +
dict_string_table[dict_string_len] * 256 + string_table[1]
local t = hash_tables[hash]
if not t then
t = {};
hash_tables[hash] = t
end
t[#t + 1] = -1
end
if block_end >= block_start + 1 and dict_string_len >= 1 then
hash =
dict_string_table[dict_string_len] * 65536 + string_table[1] * 256 +
string_table[2]
local t = hash_tables[hash]
if not t then
t = {};
hash_tables[hash] = t
end
t[#t + 1] = 0
end
end
local dict_string_len_plus3 = dict_string_len + 3
hash = (string_table[block_start - offset] or 0) * 256 +
(string_table[block_start + 1 - offset] or 0)
local lcodes = {}
local lcode_tblsize = 0
local lcodes_counts = {}
local dcodes = {}
local dcodes_tblsize = 0
local dcodes_counts = {}
local lextra_bits = {}
local lextra_bits_tblsize = 0
local dextra_bits = {}
local dextra_bits_tblsize = 0
local match_available = false
local prev_len
local prev_dist
local cur_len = 0
local cur_dist = 0
local index = block_start
local index_end = block_end + (config_use_lazy and 1 or 0)
-- the zlib source code writes separate code for lazy evaluation and
-- not lazy evaluation, which is easier to understand.
-- I put them together, so it is a bit harder to understand.
-- because I think this is easier for me to maintain it.
while (index <= index_end) do
local string_table_index = index - offset
local offset_minus_three = offset - 3
prev_len = cur_len
prev_dist = cur_dist
cur_len = 0
hash = (hash * 256 + (string_table[string_table_index + 2] or 0)) % 16777216
local chain_index
local cur_chain
local hash_chain = hash_tables[hash]
local chain_old_size
if not hash_chain then
chain_old_size = 0
hash_chain = {}
hash_tables[hash] = hash_chain
if dict_hash_tables then
cur_chain = dict_hash_tables[hash]
chain_index = cur_chain and #cur_chain or 0
else
chain_index = 0
end
else
chain_old_size = #hash_chain
cur_chain = hash_chain
chain_index = chain_old_size
end
if index <= block_end then hash_chain[chain_old_size + 1] = index end
if (chain_index > 0 and index + 2 <= block_end and
(not config_use_lazy or prev_len < config_max_lazy_match)) then
local depth =
(config_use_lazy and prev_len >= config_good_prev_length) and
config_good_hash_chain or config_max_hash_chain
local max_len_minus_one = block_end - index
max_len_minus_one = (max_len_minus_one >= 257) and 257 or
max_len_minus_one
max_len_minus_one = max_len_minus_one + string_table_index
local string_table_index_plus_three = string_table_index + 3
while chain_index >= 1 and depth > 0 do
local prev = cur_chain[chain_index]
if index - prev > 32768 then break end
if prev < index then
local sj = string_table_index_plus_three
if prev >= -257 then
local pj = prev - offset_minus_three
while (sj <= max_len_minus_one and string_table[pj] ==
string_table[sj]) do
sj = sj + 1
pj = pj + 1
end
else
local pj = dict_string_len_plus3 + prev
while (sj <= max_len_minus_one and dict_string_table[pj] ==
string_table[sj]) do
sj = sj + 1
pj = pj + 1
end
end
local j = sj - string_table_index
if j > cur_len then
cur_len = j
cur_dist = index - prev
end
if cur_len >= config_nice_length then break end
end
chain_index = chain_index - 1
depth = depth - 1
if chain_index == 0 and prev > 0 and dict_hash_tables then
cur_chain = dict_hash_tables[hash]
chain_index = cur_chain and #cur_chain or 0
end
end
end
if not config_use_lazy then prev_len, prev_dist = cur_len, cur_dist end
if ((not config_use_lazy or match_available) and
(prev_len > 3 or (prev_len == 3 and prev_dist < 4096)) and cur_len <=
prev_len) then
local code = _length_to_deflate_code[prev_len]
local length_extra_bits_bitlen = _length_to_deflate_extra_bitlen[prev_len]
local dist_code, dist_extra_bits_bitlen, dist_extra_bits
if prev_dist <= 256 then -- have cached code for small distance.
dist_code = _dist256_to_deflate_code[prev_dist]
dist_extra_bits = _dist256_to_deflate_extra_bits[prev_dist]
dist_extra_bits_bitlen = _dist256_to_deflate_extra_bitlen[prev_dist]
else
dist_code = 16
dist_extra_bits_bitlen = 7
local a = 384
local b = 512
while true do
if prev_dist <= a then
dist_extra_bits = (prev_dist - (b / 2) - 1) % (b / 4)
break
elseif prev_dist <= b then
dist_extra_bits = (prev_dist - (b / 2) - 1) % (b / 4)
dist_code = dist_code + 1
break
else
dist_code = dist_code + 2
dist_extra_bits_bitlen = dist_extra_bits_bitlen + 1
a = a * 2
b = b * 2
end
end
end
lcode_tblsize = lcode_tblsize + 1
lcodes[lcode_tblsize] = code
lcodes_counts[code] = (lcodes_counts[code] or 0) + 1
dcodes_tblsize = dcodes_tblsize + 1
dcodes[dcodes_tblsize] = dist_code
dcodes_counts[dist_code] = (dcodes_counts[dist_code] or 0) + 1
if length_extra_bits_bitlen > 0 then
local lenExtraBits = _length_to_deflate_extra_bits[prev_len]
lextra_bits_tblsize = lextra_bits_tblsize + 1
lextra_bits[lextra_bits_tblsize] = lenExtraBits
end
if dist_extra_bits_bitlen > 0 then
dextra_bits_tblsize = dextra_bits_tblsize + 1
dextra_bits[dextra_bits_tblsize] = dist_extra_bits
end
for i = index + 1, index + prev_len - (config_use_lazy and 2 or 1) do
hash = (hash * 256 + (string_table[i - offset + 2] or 0)) % 16777216
if prev_len <= config_max_insert_length then
hash_chain = hash_tables[hash]
if not hash_chain then
hash_chain = {}
hash_tables[hash] = hash_chain
end
hash_chain[#hash_chain + 1] = i
end
end
index = index + prev_len - (config_use_lazy and 1 or 0)
match_available = false
elseif (not config_use_lazy) or match_available then
local code = string_table[config_use_lazy and (string_table_index - 1) or
string_table_index]
lcode_tblsize = lcode_tblsize + 1
lcodes[lcode_tblsize] = code
lcodes_counts[code] = (lcodes_counts[code] or 0) + 1
index = index + 1
else
match_available = true
index = index + 1
end
end
-- Write "end of block" symbol
lcode_tblsize = lcode_tblsize + 1
lcodes[lcode_tblsize] = 256
lcodes_counts[256] = (lcodes_counts[256] or 0) + 1
return lcodes, lextra_bits, lcodes_counts, dcodes, dextra_bits, dcodes_counts
end
-- Get the header data of dynamic block.
-- @param lcodes_count The count of each literal/LZ77_length codes.
-- @param dcodes_count The count of each Lz77 distance codes.
-- @return a lots of stuffs.
-- @see RFC1951 Page 12
local function GetBlockDynamicHuffmanHeader(lcodes_counts, dcodes_counts)
local lcodes_huffman_bitlens, lcodes_huffman_codes, max_non_zero_bitlen_lcode =
GetHuffmanBitlenAndCode(lcodes_counts, 15, 285)
local dcodes_huffman_bitlens, dcodes_huffman_codes, max_non_zero_bitlen_dcode =
GetHuffmanBitlenAndCode(dcodes_counts, 15, 29)
local rle_deflate_codes, rle_extra_bits, rle_codes_counts =
RunLengthEncodeHuffmanBitlen(lcodes_huffman_bitlens,
max_non_zero_bitlen_lcode,
dcodes_huffman_bitlens,
max_non_zero_bitlen_dcode)
local rle_codes_huffman_bitlens, rle_codes_huffman_codes =
GetHuffmanBitlenAndCode(rle_codes_counts, 7, 18)
local HCLEN = 0
for i = 1, 19 do
local symbol = _rle_codes_huffman_bitlen_order[i]
local length = rle_codes_huffman_bitlens[symbol] or 0
if length ~= 0 then HCLEN = i end
end
HCLEN = HCLEN - 4
local HLIT = max_non_zero_bitlen_lcode + 1 - 257
local HDIST = max_non_zero_bitlen_dcode + 1 - 1
if HDIST < 0 then HDIST = 0 end
return HLIT, HDIST, HCLEN, rle_codes_huffman_bitlens, rle_codes_huffman_codes,
rle_deflate_codes, rle_extra_bits, lcodes_huffman_bitlens,
lcodes_huffman_codes, dcodes_huffman_bitlens, dcodes_huffman_codes
end
-- Get the size of dynamic block without writing any bits into the writer.
-- @param ... Read the source code of GetBlockDynamicHuffmanHeader()
-- @return the bit length of the dynamic block
local function GetDynamicHuffmanBlockSize(lcodes, dcodes, HCLEN,
rle_codes_huffman_bitlens,
rle_deflate_codes,
lcodes_huffman_bitlens,
dcodes_huffman_bitlens)
local block_bitlen = 17 -- 1+2+5+5+4
block_bitlen = block_bitlen + (HCLEN + 4) * 3
for i = 1, #rle_deflate_codes do
local code = rle_deflate_codes[i]
block_bitlen = block_bitlen + rle_codes_huffman_bitlens[code]
if code >= 16 then
block_bitlen = block_bitlen +
((code == 16) and 2 or (code == 17 and 3 or 7))
end
end
local length_code_count = 0
for i = 1, #lcodes do
local code = lcodes[i]
local huffman_bitlen = lcodes_huffman_bitlens[code]
block_bitlen = block_bitlen + huffman_bitlen
if code > 256 then -- Length code
length_code_count = length_code_count + 1
if code > 264 and code < 285 then -- Length code with extra bits
local extra_bits_bitlen = _literal_deflate_code_to_extra_bitlen[code -
256]
block_bitlen = block_bitlen + extra_bits_bitlen
end
local dist_code = dcodes[length_code_count]
local dist_huffman_bitlen = dcodes_huffman_bitlens[dist_code]
block_bitlen = block_bitlen + dist_huffman_bitlen
if dist_code > 3 then -- dist code with extra bits
local dist_extra_bits_bitlen = (dist_code - dist_code % 2) / 2 - 1
block_bitlen = block_bitlen + dist_extra_bits_bitlen
end
end
end
return block_bitlen
end
-- Write dynamic block.
-- @param ... Read the source code of GetBlockDynamicHuffmanHeader()
local function CompressDynamicHuffmanBlock(WriteBits, is_last_block, lcodes,
lextra_bits, dcodes, dextra_bits,
HLIT, HDIST, HCLEN,
rle_codes_huffman_bitlens,
rle_codes_huffman_codes,
rle_deflate_codes, rle_extra_bits,
lcodes_huffman_bitlens,
lcodes_huffman_codes,
dcodes_huffman_bitlens,
dcodes_huffman_codes)
WriteBits(is_last_block and 1 or 0, 1) -- Last block identifier
WriteBits(2, 2) -- Dynamic Huffman block identifier
WriteBits(HLIT, 5)
WriteBits(HDIST, 5)
WriteBits(HCLEN, 4)
for i = 1, HCLEN + 4 do
local symbol = _rle_codes_huffman_bitlen_order[i]
local length = rle_codes_huffman_bitlens[symbol] or 0
WriteBits(length, 3)
end
local rleExtraBitsIndex = 1
for i = 1, #rle_deflate_codes do
local code = rle_deflate_codes[i]
WriteBits(rle_codes_huffman_codes[code], rle_codes_huffman_bitlens[code])
if code >= 16 then
local extraBits = rle_extra_bits[rleExtraBitsIndex]
WriteBits(extraBits, (code == 16) and 2 or (code == 17 and 3 or 7))
rleExtraBitsIndex = rleExtraBitsIndex + 1
end
end
local length_code_count = 0
local length_code_with_extra_count = 0
local dist_code_with_extra_count = 0
for i = 1, #lcodes do
local deflate_codee = lcodes[i]
local huffman_code = lcodes_huffman_codes[deflate_codee]
local huffman_bitlen = lcodes_huffman_bitlens[deflate_codee]
WriteBits(huffman_code, huffman_bitlen)
if deflate_codee > 256 then -- Length code
length_code_count = length_code_count + 1
if deflate_codee > 264 and deflate_codee < 285 then
-- Length code with extra bits
length_code_with_extra_count = length_code_with_extra_count + 1
local extra_bits = lextra_bits[length_code_with_extra_count]
local extra_bits_bitlen =
_literal_deflate_code_to_extra_bitlen[deflate_codee - 256]
WriteBits(extra_bits, extra_bits_bitlen)
end
-- Write distance code
local dist_deflate_code = dcodes[length_code_count]
local dist_huffman_code = dcodes_huffman_codes[dist_deflate_code]
local dist_huffman_bitlen = dcodes_huffman_bitlens[dist_deflate_code]
WriteBits(dist_huffman_code, dist_huffman_bitlen)
if dist_deflate_code > 3 then -- dist code with extra bits
dist_code_with_extra_count = dist_code_with_extra_count + 1
local dist_extra_bits = dextra_bits[dist_code_with_extra_count]
local dist_extra_bits_bitlen = (dist_deflate_code - dist_deflate_code %
2) / 2 - 1
WriteBits(dist_extra_bits, dist_extra_bits_bitlen)
end
end
end
end
-- Get the size of fixed block without writing any bits into the writer.
-- @param lcodes literal/LZ77_length deflate codes
-- @param decodes LZ77 distance deflate codes
-- @return the bit length of the fixed block
local function GetFixedHuffmanBlockSize(lcodes, dcodes)
local block_bitlen = 3
local length_code_count = 0
for i = 1, #lcodes do
local code = lcodes[i]
local huffman_bitlen = _fix_block_literal_huffman_bitlen[code]
block_bitlen = block_bitlen + huffman_bitlen
if code > 256 then -- Length code
length_code_count = length_code_count + 1
if code > 264 and code < 285 then -- Length code with extra bits
local extra_bits_bitlen = _literal_deflate_code_to_extra_bitlen[code -
256]
block_bitlen = block_bitlen + extra_bits_bitlen
end
local dist_code = dcodes[length_code_count]
block_bitlen = block_bitlen + 5
if dist_code > 3 then -- dist code with extra bits
local dist_extra_bits_bitlen = (dist_code - dist_code % 2) / 2 - 1
block_bitlen = block_bitlen + dist_extra_bits_bitlen
end
end
end
return block_bitlen
end
-- Write fixed block.
-- @param lcodes literal/LZ77_length deflate codes
-- @param decodes LZ77 distance deflate codes
local function CompressFixedHuffmanBlock(WriteBits, is_last_block, lcodes,
lextra_bits, dcodes, dextra_bits)
WriteBits(is_last_block and 1 or 0, 1) -- Last block identifier
WriteBits(1, 2) -- Fixed Huffman block identifier
local length_code_count = 0
local length_code_with_extra_count = 0
local dist_code_with_extra_count = 0
for i = 1, #lcodes do
local deflate_code = lcodes[i]
local huffman_code = _fix_block_literal_huffman_code[deflate_code]
local huffman_bitlen = _fix_block_literal_huffman_bitlen[deflate_code]
WriteBits(huffman_code, huffman_bitlen)
if deflate_code > 256 then -- Length code
length_code_count = length_code_count + 1
if deflate_code > 264 and deflate_code < 285 then
-- Length code with extra bits
length_code_with_extra_count = length_code_with_extra_count + 1
local extra_bits = lextra_bits[length_code_with_extra_count]
local extra_bits_bitlen =
_literal_deflate_code_to_extra_bitlen[deflate_code - 256]
WriteBits(extra_bits, extra_bits_bitlen)
end
-- Write distance code
local dist_code = dcodes[length_code_count]
local dist_huffman_code = _fix_block_dist_huffman_code[dist_code]
WriteBits(dist_huffman_code, 5)
if dist_code > 3 then -- dist code with extra bits
dist_code_with_extra_count = dist_code_with_extra_count + 1
local dist_extra_bits = dextra_bits[dist_code_with_extra_count]
local dist_extra_bits_bitlen = (dist_code - dist_code % 2) / 2 - 1
WriteBits(dist_extra_bits, dist_extra_bits_bitlen)
end
end
end
end
-- Get the size of store block without writing any bits into the writer.
-- @param block_start The start index of the origin input string
-- @param block_end The end index of the origin input string
-- @param Total bit lens had been written into the compressed result before,
-- because store block needs to shift to byte boundary.
-- @return the bit length of the fixed block
local function GetStoreBlockSize(block_start, block_end, total_bitlen)
assert(block_end - block_start + 1 <= 65535)
local block_bitlen = 3
total_bitlen = total_bitlen + 3
local padding_bitlen = (8 - total_bitlen % 8) % 8
block_bitlen = block_bitlen + padding_bitlen
block_bitlen = block_bitlen + 32
block_bitlen = block_bitlen + (block_end - block_start + 1) * 8
return block_bitlen
end
-- Write the store block.
-- @param ... lots of stuffs
-- @return nil
local function CompressStoreBlock(WriteBits, WriteString, is_last_block, str,
block_start, block_end, total_bitlen)
assert(block_end - block_start + 1 <= 65535)
WriteBits(is_last_block and 1 or 0, 1) -- Last block identifer.
WriteBits(0, 2) -- Store block identifier.
total_bitlen = total_bitlen + 3
local padding_bitlen = (8 - total_bitlen % 8) % 8
if padding_bitlen > 0 then
WriteBits(_pow2[padding_bitlen] - 1, padding_bitlen)
end
local size = block_end - block_start + 1
WriteBits(size, 16)
-- Write size's one's complement
local comp = (255 - size % 256) + (255 - (size - size % 256) / 256) * 256
WriteBits(comp, 16)
WriteString(str:sub(block_start, block_end))
end
-- Do the deflate
-- Currently using a simple way to determine the block size
-- (This is why the compression ratio is little bit worse than zlib when
-- the input size is very large
-- The first block is 64KB, the following block is 32KB.
-- After each block, there is a memory cleanup operation.
-- This is not a fast operation, but it is needed to save memory usage, so
-- the memory usage does not grow unboundly. If the data size is less than
-- 64KB, then memory cleanup won't happen.
-- This function determines whether to use store/fixed/dynamic blocks by
-- calculating the block size of each block type and chooses the smallest one.
local function Deflate(configs, WriteBits, WriteString, FlushWriter, str,
dictionary)
local string_table = {}
local hash_tables = {}
local is_last_block = nil
local block_start
local block_end
local bitlen_written
local total_bitlen = FlushWriter(_FLUSH_MODE_NO_FLUSH)
local strlen = #str
local offset
local level
local strategy
if configs then
if configs.level then level = configs.level end
if configs.strategy then strategy = configs.strategy end
end
if not level then
if strlen < 2048 then
level = 7
elseif strlen > 65536 then
level = 3
else
level = 5
end
end
while not is_last_block do
if not block_start then
block_start = 1
block_end = 64 * 1024 - 1
offset = 0
else
block_start = block_end + 1
block_end = block_end + 32 * 1024
offset = block_start - 32 * 1024 - 1
end
if block_end >= strlen then
block_end = strlen
is_last_block = true
else
is_last_block = false
end
local lcodes, lextra_bits, lcodes_counts, dcodes, dextra_bits, dcodes_counts
local HLIT, HDIST, HCLEN, rle_codes_huffman_bitlens,
rle_codes_huffman_codes, rle_deflate_codes, rle_extra_bits,
lcodes_huffman_bitlens, lcodes_huffman_codes, dcodes_huffman_bitlens,
dcodes_huffman_codes
local dynamic_block_bitlen
local fixed_block_bitlen
local store_block_bitlen
if level ~= 0 then
-- GetBlockLZ77 needs block_start to block_end+3 to be loaded.
LoadStringToTable(str, string_table, block_start, block_end + 3, offset)
if block_start == 1 and dictionary then
local dict_string_table = dictionary.string_table
local dict_strlen = dictionary.strlen
for i = 0, (-dict_strlen + 1) < -257 and -257 or (-dict_strlen + 1), -1 do
string_table[i] = dict_string_table[dict_strlen + i]
end
end
if strategy == "huffman_only" then
lcodes = {}
LoadStringToTable(str, lcodes, block_start, block_end, block_start - 1)
lextra_bits = {}
lcodes_counts = {}
lcodes[block_end - block_start + 2] = 256 -- end of block
for i = 1, block_end - block_start + 2 do
local code = lcodes[i]
lcodes_counts[code] = (lcodes_counts[code] or 0) + 1
end
dcodes = {}
dextra_bits = {}
dcodes_counts = {}
else
lcodes, lextra_bits, lcodes_counts, dcodes, dextra_bits, dcodes_counts =
GetBlockLZ77Result(level, string_table, hash_tables, block_start,
block_end, offset, dictionary)
end
-- LuaFormatter off
HLIT, HDIST, HCLEN, rle_codes_huffman_bitlens, rle_codes_huffman_codes, rle_deflate_codes,
rle_extra_bits, lcodes_huffman_bitlens, lcodes_huffman_codes, dcodes_huffman_bitlens, dcodes_huffman_codes =
-- LuaFormatter on
GetBlockDynamicHuffmanHeader(lcodes_counts, dcodes_counts)
dynamic_block_bitlen = GetDynamicHuffmanBlockSize(lcodes, dcodes, HCLEN,
rle_codes_huffman_bitlens,
rle_deflate_codes,
lcodes_huffman_bitlens,
dcodes_huffman_bitlens)
fixed_block_bitlen = GetFixedHuffmanBlockSize(lcodes, dcodes)
end
store_block_bitlen = GetStoreBlockSize(block_start, block_end, total_bitlen)
local min_bitlen = store_block_bitlen
min_bitlen = (fixed_block_bitlen and fixed_block_bitlen < min_bitlen) and
fixed_block_bitlen or min_bitlen
min_bitlen =
(dynamic_block_bitlen and dynamic_block_bitlen < min_bitlen) and
dynamic_block_bitlen or min_bitlen
if level == 0 or
(strategy ~= "fixed" and strategy ~= "dynamic" and store_block_bitlen ==
min_bitlen) then
CompressStoreBlock(WriteBits, WriteString, is_last_block, str,
block_start, block_end, total_bitlen)
total_bitlen = total_bitlen + store_block_bitlen
elseif strategy ~= "dynamic" and
(strategy == "fixed" or fixed_block_bitlen == min_bitlen) then
CompressFixedHuffmanBlock(WriteBits, is_last_block, lcodes, lextra_bits,
dcodes, dextra_bits)
total_bitlen = total_bitlen + fixed_block_bitlen
elseif strategy == "dynamic" or dynamic_block_bitlen == min_bitlen then
CompressDynamicHuffmanBlock(WriteBits, is_last_block, lcodes, lextra_bits,
dcodes, dextra_bits, HLIT, HDIST, HCLEN,
rle_codes_huffman_bitlens,
rle_codes_huffman_codes, rle_deflate_codes,
rle_extra_bits, lcodes_huffman_bitlens,
lcodes_huffman_codes, dcodes_huffman_bitlens,
dcodes_huffman_codes)
total_bitlen = total_bitlen + dynamic_block_bitlen
end
if is_last_block then
bitlen_written = FlushWriter(_FLUSH_MODE_NO_FLUSH)
else
bitlen_written = FlushWriter(_FLUSH_MODE_MEMORY_CLEANUP)
end
assert(bitlen_written == total_bitlen)
-- Memory clean up, so memory consumption does not always grow linearly
-- , even if input string is > 64K.
-- Not a very efficient operation, but this operation won't happen
-- when the input data size is less than 64K.
if not is_last_block then
local j
if dictionary and block_start == 1 then
j = 0
while (string_table[j]) do
string_table[j] = nil
j = j - 1
end
end
dictionary = nil
j = 1
for i = block_end - 32767, block_end do
string_table[j] = string_table[i - offset]
j = j + 1
end
for k, t in pairs(hash_tables) do
local tSize = #t
if tSize > 0 and block_end + 1 - t[1] > 32768 then
if tSize == 1 then
hash_tables[k] = nil
else
local new = {}
local newSize = 0
for i = 2, tSize do
j = t[i]
if block_end + 1 - j <= 32768 then
newSize = newSize + 1
new[newSize] = j
end
end
hash_tables[k] = new
end
end
end
end
end
end
--- The description to compression configuration table. <br>
-- Any field can be nil to use its default. <br>
-- Table with keys other than those below is an invalid table.
-- @class table
-- @name compression_configs
-- @field level The compression level ranged from 0 to 9. 0 is no compression.
-- 9 is the slowest but best compression. Use nil for default level.
-- @field strategy The compression strategy. "fixed" to only use fixed deflate
-- compression block. "dynamic" to only use dynamic block. "huffman_only" to
-- do no LZ77 compression. Only do huffman compression.
-- @see LibDeflate:CompressDeflate(str, configs)
-- @see LibDeflate:CompressDeflateWithDict(str, dictionary, configs)
local function CompressDeflateInternal(str, dictionary, configs)
local WriteBits, WriteString, FlushWriter = CreateWriter()
Deflate(configs, WriteBits, WriteString, FlushWriter, str, dictionary)
local total_bitlen, result = FlushWriter(_FLUSH_MODE_OUTPUT)
local padding_bitlen = (8 - total_bitlen % 8) % 8
return result, padding_bitlen
end
-- @see LibDeflate:CompressZlib
-- @see LibDeflate:CompressZlibWithDict
local function CompressZlibInternal(str, dictionary, configs)
local WriteBits, WriteString, FlushWriter = CreateWriter()
local CM = 8 -- Compression method
local CINFO = 7 -- Window Size = 32K
local CMF = CINFO * 16 + CM
WriteBits(CMF, 8)
local FDIST = dictionary and 1 or 0
local FLEVEL = 2 -- Default compression
local FLG = FLEVEL * 64 + FDIST * 32
local FCHECK = (31 - (CMF * 256 + FLG) % 31)
-- The FCHECK value must be such that CMF and FLG,
-- when viewed as a 16-bit unsigned integer stored
-- in MSB order (CMF*256 + FLG), is a multiple of 31.
FLG = FLG + FCHECK
WriteBits(FLG, 8)
if FDIST == 1 then
local adler32 = dictionary.adler32
local byte0 = adler32 % 256
adler32 = (adler32 - byte0) / 256
local byte1 = adler32 % 256
adler32 = (adler32 - byte1) / 256
local byte2 = adler32 % 256
adler32 = (adler32 - byte2) / 256
local byte3 = adler32 % 256
WriteBits(byte3, 8)
WriteBits(byte2, 8)
WriteBits(byte1, 8)
WriteBits(byte0, 8)
end
Deflate(configs, WriteBits, WriteString, FlushWriter, str, dictionary)
FlushWriter(_FLUSH_MODE_BYTE_BOUNDARY)
local adler32 = LibDeflate:Adler32(str)
-- Most significant byte first
local byte3 = adler32 % 256
adler32 = (adler32 - byte3) / 256
local byte2 = adler32 % 256
adler32 = (adler32 - byte2) / 256
local byte1 = adler32 % 256
adler32 = (adler32 - byte1) / 256
local byte0 = adler32 % 256
WriteBits(byte0, 8)
WriteBits(byte1, 8)
WriteBits(byte2, 8)
WriteBits(byte3, 8)
local total_bitlen, result = FlushWriter(_FLUSH_MODE_OUTPUT)
local padding_bitlen = (8 - total_bitlen % 8) % 8
return result, padding_bitlen
end
--- Compress using the raw deflate format.
-- @param str [string] The data to be compressed.
-- @param configs [table/nil] The configuration table to control the compression
-- . If nil, use the default configuration.
-- @return [string] The compressed data.
-- @return [integer] The number of bits padded at the end of output.
-- 0 <= bits < 8 <br>
-- This means the most significant "bits" of the last byte of the returned
-- compressed data are padding bits and they don't affect decompression.
-- You don't need to use this value unless you want to do some postprocessing
-- to the compressed data.
-- @see compression_configs
-- @see LibDeflate:DecompressDeflate
function LibDeflate:CompressDeflate(str, configs)
local arg_valid, arg_err = IsValidArguments(str, false, nil, true, configs)
if not arg_valid then
error(("Usage: LibDeflate:CompressDeflate(str, configs): " .. arg_err), 2)
end
return CompressDeflateInternal(str, nil, configs)
end
--- Compress using the raw deflate format with a preset dictionary.
-- @param str [string] The data to be compressed.
-- @param dictionary [table] The preset dictionary produced by
-- LibDeflate:CreateDictionary
-- @param configs [table/nil] The configuration table to control the compression
-- . If nil, use the default configuration.
-- @return [string] The compressed data.
-- @return [integer] The number of bits padded at the end of output.
-- 0 <= bits < 8 <br>
-- This means the most significant "bits" of the last byte of the returned
-- compressed data are padding bits and they don't affect decompression.
-- You don't need to use this value unless you want to do some postprocessing
-- to the compressed data.
-- @see compression_configs
-- @see LibDeflate:CreateDictionary
-- @see LibDeflate:DecompressDeflateWithDict
function LibDeflate:CompressDeflateWithDict(str, dictionary, configs)
local arg_valid, arg_err = IsValidArguments(str, true, dictionary, true,
configs)
if not arg_valid then
error(("Usage: LibDeflate:CompressDeflateWithDict" ..
"(str, dictionary, configs): " .. arg_err), 2)
end
return CompressDeflateInternal(str, dictionary, configs)
end
--- Compress using the zlib format.
-- @param str [string] the data to be compressed.
-- @param configs [table/nil] The configuration table to control the compression
-- . If nil, use the default configuration.
-- @return [string] The compressed data.
-- @return [integer] The number of bits padded at the end of output.
-- Should always be 0.
-- Zlib formatted compressed data never has padding bits at the end.
-- @see compression_configs
-- @see LibDeflate:DecompressZlib
function LibDeflate:CompressZlib(str, configs)
local arg_valid, arg_err = IsValidArguments(str, false, nil, true, configs)
if not arg_valid then
error(("Usage: LibDeflate:CompressZlib(str, configs): " .. arg_err), 2)
end
return CompressZlibInternal(str, nil, configs)
end
--- Compress using the zlib format with a preset dictionary.
-- @param str [string] the data to be compressed.
-- @param dictionary [table] A preset dictionary produced
-- by LibDeflate:CreateDictionary()
-- @param configs [table/nil] The configuration table to control the compression
-- . If nil, use the default configuration.
-- @return [string] The compressed data.
-- @return [integer] The number of bits padded at the end of output.
-- Should always be 0.
-- Zlib formatted compressed data never has padding bits at the end.
-- @see compression_configs
-- @see LibDeflate:CreateDictionary
-- @see LibDeflate:DecompressZlibWithDict
function LibDeflate:CompressZlibWithDict(str, dictionary, configs)
local arg_valid, arg_err = IsValidArguments(str, true, dictionary, true,
configs)
if not arg_valid then
error(("Usage: LibDeflate:CompressZlibWithDict" ..
"(str, dictionary, configs): " .. arg_err), 2)
end
return CompressZlibInternal(str, dictionary, configs)
end
--[[ --------------------------------------------------------------------------
Decompress code
--]] --------------------------------------------------------------------------
--[[
Create a reader to easily reader stuffs as the unit of bits.
Return values:
1. ReadBits(bitlen)
2. ReadBytes(bytelen, buffer, buffer_size)
3. Decode(huffman_bitlen_count, huffman_symbol, min_bitlen)
4. ReaderBitlenLeft()
5. SkipToByteBoundary()
--]]
local function CreateReader(input_string)
local input = input_string
local input_strlen = #input_string
local input_next_byte_pos = 1
local cache_bitlen = 0
local cache = 0
-- Read some bits.
-- To improve speed, this function does not
-- check if the input has been exhausted.
-- Use ReaderBitlenLeft() < 0 to check it.
-- @param bitlen the number of bits to read
-- @return the data is read.
local function ReadBits(bitlen)
local rshift_mask = _pow2[bitlen]
local code
if bitlen <= cache_bitlen then
code = cache % rshift_mask
cache = (cache - code) / rshift_mask
cache_bitlen = cache_bitlen - bitlen
else -- Whether input has been exhausted is not checked.
local lshift_mask = _pow2[cache_bitlen]
local byte1, byte2, byte3, byte4 =
string_byte(input, input_next_byte_pos, input_next_byte_pos + 3)
-- This requires lua number to be at least double ()
cache = cache +
((byte1 or 0) + (byte2 or 0) * 256 + (byte3 or 0) * 65536 +
(byte4 or 0) * 16777216) * lshift_mask
input_next_byte_pos = input_next_byte_pos + 4
cache_bitlen = cache_bitlen + 32 - bitlen
code = cache % rshift_mask
cache = (cache - code) / rshift_mask
end
return code
end
-- Read some bytes from the reader.
-- Assume reader is on the byte boundary.
-- @param bytelen The number of bytes to be read.
-- @param buffer The byte read will be stored into this buffer.
-- @param buffer_size The buffer will be modified starting from
-- buffer[buffer_size+1], ending at buffer[buffer_size+bytelen-1]
-- @return the new buffer_size
local function ReadBytes(bytelen, buffer, buffer_size)
assert(cache_bitlen % 8 == 0)
local byte_from_cache =
(cache_bitlen / 8 < bytelen) and (cache_bitlen / 8) or bytelen
for _ = 1, byte_from_cache do
local byte = cache % 256
buffer_size = buffer_size + 1
buffer[buffer_size] = string_char(byte)
cache = (cache - byte) / 256
end
cache_bitlen = cache_bitlen - byte_from_cache * 8
bytelen = bytelen - byte_from_cache
if (input_strlen - input_next_byte_pos - bytelen + 1) * 8 + cache_bitlen < 0 then
return -1 -- out of input
end
for i = input_next_byte_pos, input_next_byte_pos + bytelen - 1 do
buffer_size = buffer_size + 1
buffer[buffer_size] = string_sub(input, i, i)
end
input_next_byte_pos = input_next_byte_pos + bytelen
return buffer_size
end
-- Decode huffman code
-- To improve speed, this function does not check
-- if the input has been exhausted.
-- Use ReaderBitlenLeft() < 0 to check it.
-- Credits for Mark Adler. This code is from puff:Decode()
-- @see puff:Decode(...)
-- @param huffman_bitlen_count
-- @param huffman_symbol
-- @param min_bitlen The minimum huffman bit length of all symbols
-- @return The decoded deflate code.
-- Negative value is returned if decoding fails.
local function Decode(huffman_bitlen_counts, huffman_symbols, min_bitlen)
local code = 0
local first = 0
local index = 0
local count
if min_bitlen > 0 then
if cache_bitlen < 15 and input then
local lshift_mask = _pow2[cache_bitlen]
local byte1, byte2, byte3, byte4 =
string_byte(input, input_next_byte_pos, input_next_byte_pos + 3)
-- This requires lua number to be at least double ()
cache = cache +
((byte1 or 0) + (byte2 or 0) * 256 + (byte3 or 0) * 65536 +
(byte4 or 0) * 16777216) * lshift_mask
input_next_byte_pos = input_next_byte_pos + 4
cache_bitlen = cache_bitlen + 32
end
local rshift_mask = _pow2[min_bitlen]
cache_bitlen = cache_bitlen - min_bitlen
code = cache % rshift_mask
cache = (cache - code) / rshift_mask
-- Reverse the bits
code = _reverse_bits_tbl[min_bitlen][code]
count = huffman_bitlen_counts[min_bitlen]
if code < count then return huffman_symbols[code] end
index = count
first = count * 2
code = code * 2
end
for bitlen = min_bitlen + 1, 15 do
local bit
bit = cache % 2
cache = (cache - bit) / 2
cache_bitlen = cache_bitlen - 1
code = (bit == 1) and (code + 1 - code % 2) or code
count = huffman_bitlen_counts[bitlen] or 0
local diff = code - first
if diff < count then return huffman_symbols[index + diff] end
index = index + count
first = first + count
first = first * 2
code = code * 2
end
-- invalid literal/length or distance code
-- in fixed or dynamic block (run out of code)
return -10
end
local function ReaderBitlenLeft()
return (input_strlen - input_next_byte_pos + 1) * 8 + cache_bitlen
end
local function SkipToByteBoundary()
local skipped_bitlen = cache_bitlen % 8
local rshift_mask = _pow2[skipped_bitlen]
cache_bitlen = cache_bitlen - skipped_bitlen
cache = (cache - cache % rshift_mask) / rshift_mask
end
return ReadBits, ReadBytes, Decode, ReaderBitlenLeft, SkipToByteBoundary
end
-- Create a deflate state, so I can pass in less arguments to functions.
-- @param str the whole string to be decompressed.
-- @param dictionary The preset dictionary. nil if not provided.
-- This dictionary should be produced by LibDeflate:CreateDictionary(str)
-- @return The decomrpess state.
local function CreateDecompressState(str, dictionary)
local ReadBits, ReadBytes, Decode, ReaderBitlenLeft, SkipToByteBoundary =
CreateReader(str)
local state = {
ReadBits = ReadBits,
ReadBytes = ReadBytes,
Decode = Decode,
ReaderBitlenLeft = ReaderBitlenLeft,
SkipToByteBoundary = SkipToByteBoundary,
buffer_size = 0,
buffer = {},
result_buffer = {},
dictionary = dictionary
}
return state
end
-- Get the stuffs needed to decode huffman codes
-- @see puff.c:construct(...)
-- @param huffman_bitlen The huffman bit length of the huffman codes.
-- @param max_symbol The maximum symbol
-- @param max_bitlen The min huffman bit length of all codes
-- @return zero or positive for success, negative for failure.
-- @return The count of each huffman bit length.
-- @return A table to convert huffman codes to deflate codes.
-- @return The minimum huffman bit length.
local function GetHuffmanForDecode(huffman_bitlens, max_symbol, max_bitlen)
local huffman_bitlen_counts = {}
local min_bitlen = max_bitlen
for symbol = 0, max_symbol do
local bitlen = huffman_bitlens[symbol] or 0
min_bitlen = (bitlen > 0 and bitlen < min_bitlen) and bitlen or min_bitlen
huffman_bitlen_counts[bitlen] = (huffman_bitlen_counts[bitlen] or 0) + 1
end
if huffman_bitlen_counts[0] == max_symbol + 1 then -- No Codes
return 0, huffman_bitlen_counts, {}, 0 -- Complete, but decode will fail
end
local left = 1
for len = 1, max_bitlen do
left = left * 2
left = left - (huffman_bitlen_counts[len] or 0)
if left < 0 then
return left -- Over-subscribed, return negative
end
end
-- Generate offsets info symbol table for each length for sorting
local offsets = {}
offsets[1] = 0
for len = 1, max_bitlen - 1 do
offsets[len + 1] = offsets[len] + (huffman_bitlen_counts[len] or 0)
end
local huffman_symbols = {}
for symbol = 0, max_symbol do
local bitlen = huffman_bitlens[symbol] or 0
if bitlen ~= 0 then
local offset = offsets[bitlen]
huffman_symbols[offset] = symbol
offsets[bitlen] = offsets[bitlen] + 1
end
end
-- Return zero for complete set, positive for incomplete set.
return left, huffman_bitlen_counts, huffman_symbols, min_bitlen
end
-- Decode a fixed or dynamic huffman blocks, excluding last block identifier
-- and block type identifer.
-- @see puff.c:codes()
-- @param state decompression state that will be modified by this function.
-- @see CreateDecompressState
-- @param ... Read the source code
-- @return 0 on success, other value on failure.
local function DecodeUntilEndOfBlock(state, lcodes_huffman_bitlens,
lcodes_huffman_symbols,
lcodes_huffman_min_bitlen,
dcodes_huffman_bitlens,
dcodes_huffman_symbols,
dcodes_huffman_min_bitlen)
local buffer, buffer_size, ReadBits, Decode, ReaderBitlenLeft, result_buffer =
state.buffer, state.buffer_size, state.ReadBits, state.Decode,
state.ReaderBitlenLeft, state.result_buffer
local dictionary = state.dictionary
local dict_string_table
local dict_strlen
local buffer_end = 1
if dictionary and not buffer[0] then
-- If there is a dictionary, copy the last 258 bytes into
-- the string_table to make the copy in the main loop quicker.
-- This is done only once per decompression.
dict_string_table = dictionary.string_table
dict_strlen = dictionary.strlen
buffer_end = -dict_strlen + 1
for i = 0, (-dict_strlen + 1) < -257 and -257 or (-dict_strlen + 1), -1 do
buffer[i] = _byte_to_char[dict_string_table[dict_strlen + i]]
end
end
repeat
local symbol = Decode(lcodes_huffman_bitlens, lcodes_huffman_symbols,
lcodes_huffman_min_bitlen)
if symbol < 0 or symbol > 285 then
-- invalid literal/length or distance code in fixed or dynamic block
return -10
elseif symbol < 256 then -- Literal
buffer_size = buffer_size + 1
buffer[buffer_size] = _byte_to_char[symbol]
elseif symbol > 256 then -- Length code
symbol = symbol - 256
local bitlen = _literal_deflate_code_to_base_len[symbol]
bitlen = (symbol >= 8) and
(bitlen +
ReadBits(_literal_deflate_code_to_extra_bitlen[symbol])) or
bitlen
symbol = Decode(dcodes_huffman_bitlens, dcodes_huffman_symbols,
dcodes_huffman_min_bitlen)
if symbol < 0 or symbol > 29 then
-- invalid literal/length or distance code in fixed or dynamic block
return -10
end
local dist = _dist_deflate_code_to_base_dist[symbol]
dist = (dist > 4) and
(dist + ReadBits(_dist_deflate_code_to_extra_bitlen[symbol])) or
dist
local char_buffer_index = buffer_size - dist + 1
if char_buffer_index < buffer_end then
-- distance is too far back in fixed or dynamic block
return -11
end
if char_buffer_index >= -257 then
for _ = 1, bitlen do
buffer_size = buffer_size + 1
buffer[buffer_size] = buffer[char_buffer_index]
char_buffer_index = char_buffer_index + 1
end
else
char_buffer_index = dict_strlen + char_buffer_index
for _ = 1, bitlen do
buffer_size = buffer_size + 1
buffer[buffer_size] =
_byte_to_char[dict_string_table[char_buffer_index]]
char_buffer_index = char_buffer_index + 1
end
end
end
if ReaderBitlenLeft() < 0 then
return 2 -- available inflate data did not terminate
end
if buffer_size >= 65536 then
result_buffer[#result_buffer + 1] = table_concat(buffer, "", 1, 32768)
for i = 32769, buffer_size do buffer[i - 32768] = buffer[i] end
buffer_size = buffer_size - 32768
buffer[buffer_size + 1] = nil
-- NOTE: buffer[32769..end] and buffer[-257..0] are not cleared.
-- This is why "buffer_size" variable is needed.
end
until symbol == 256
state.buffer_size = buffer_size
return 0
end
-- Decompress a store block
-- @param state decompression state that will be modified by this function.
-- @return 0 if succeeds, other value if fails.
local function DecompressStoreBlock(state)
local buffer, buffer_size, ReadBits, ReadBytes, ReaderBitlenLeft,
SkipToByteBoundary, result_buffer = state.buffer, state.buffer_size,
state.ReadBits, state.ReadBytes,
state.ReaderBitlenLeft,
state.SkipToByteBoundary,
state.result_buffer
SkipToByteBoundary()
local bytelen = ReadBits(16)
if ReaderBitlenLeft() < 0 then
return 2 -- available inflate data did not terminate
end
local bytelenComp = ReadBits(16)
if ReaderBitlenLeft() < 0 then
return 2 -- available inflate data did not terminate
end
if bytelen % 256 + bytelenComp % 256 ~= 255 then
return -2 -- Not one's complement
end
if (bytelen - bytelen % 256) / 256 + (bytelenComp - bytelenComp % 256) / 256 ~=
255 then
return -2 -- Not one's complement
end
-- Note that ReadBytes will skip to the next byte boundary first.
buffer_size = ReadBytes(bytelen, buffer, buffer_size)
if buffer_size < 0 then
return 2 -- available inflate data did not terminate
end
-- memory clean up when there are enough bytes in the buffer.
if buffer_size >= 65536 then
result_buffer[#result_buffer + 1] = table_concat(buffer, "", 1, 32768)
for i = 32769, buffer_size do buffer[i - 32768] = buffer[i] end
buffer_size = buffer_size - 32768
buffer[buffer_size + 1] = nil
end
state.buffer_size = buffer_size
return 0
end
-- Decompress a fixed block
-- @param state decompression state that will be modified by this function.
-- @return 0 if succeeds other value if fails.
local function DecompressFixBlock(state)
return DecodeUntilEndOfBlock(state, _fix_block_literal_huffman_bitlen_count,
_fix_block_literal_huffman_to_deflate_code, 7,
_fix_block_dist_huffman_bitlen_count,
_fix_block_dist_huffman_to_deflate_code, 5)
end
-- Decompress a dynamic block
-- @param state decompression state that will be modified by this function.
-- @return 0 if success, other value if fails.
local function DecompressDynamicBlock(state)
local ReadBits, Decode = state.ReadBits, state.Decode
local nlen = ReadBits(5) + 257
local ndist = ReadBits(5) + 1
local ncode = ReadBits(4) + 4
if nlen > 286 or ndist > 30 then
-- dynamic block code description: too many length or distance codes
return -3
end
local rle_codes_huffman_bitlens = {}
for i = 1, ncode do
rle_codes_huffman_bitlens[_rle_codes_huffman_bitlen_order[i]] = ReadBits(3)
end
local rle_codes_err, rle_codes_huffman_bitlen_counts,
rle_codes_huffman_symbols, rle_codes_huffman_min_bitlen =
GetHuffmanForDecode(rle_codes_huffman_bitlens, 18, 7)
if rle_codes_err ~= 0 then -- Require complete code set here
-- dynamic block code description: code lengths codes incomplete
return -4
end
local lcodes_huffman_bitlens = {}
local dcodes_huffman_bitlens = {}
-- Read length/literal and distance code length tables
local index = 0
while index < nlen + ndist do
local symbol -- Decoded value
local bitlen -- Last length to repeat
symbol = Decode(rle_codes_huffman_bitlen_counts, rle_codes_huffman_symbols,
rle_codes_huffman_min_bitlen)
if symbol < 0 then
return symbol -- Invalid symbol
elseif symbol < 16 then
if index < nlen then
lcodes_huffman_bitlens[index] = symbol
else
dcodes_huffman_bitlens[index - nlen] = symbol
end
index = index + 1
else
bitlen = 0
if symbol == 16 then
if index == 0 then
-- dynamic block code description: repeat lengths
-- with no first length
return -5
end
if index - 1 < nlen then
bitlen = lcodes_huffman_bitlens[index - 1]
else
bitlen = dcodes_huffman_bitlens[index - nlen - 1]
end
symbol = 3 + ReadBits(2)
elseif symbol == 17 then -- Repeat zero 3..10 times
symbol = 3 + ReadBits(3)
else -- == 18, repeat zero 11.138 times
symbol = 11 + ReadBits(7)
end
if index + symbol > nlen + ndist then
-- dynamic block code description:
-- repeat more than specified lengths
return -6
end
while symbol > 0 do -- Repeat last or zero symbol times
symbol = symbol - 1
if index < nlen then
lcodes_huffman_bitlens[index] = bitlen
else
dcodes_huffman_bitlens[index - nlen] = bitlen
end
index = index + 1
end
end
end
if (lcodes_huffman_bitlens[256] or 0) == 0 then
-- dynamic block code description: missing end-of-block code
return -9
end
local lcodes_err, lcodes_huffman_bitlen_counts, lcodes_huffman_symbols,
lcodes_huffman_min_bitlen = GetHuffmanForDecode(lcodes_huffman_bitlens,
nlen - 1, 15)
-- dynamic block code description: invalid literal/length code lengths,
-- Incomplete code ok only for single length 1 code
if (lcodes_err ~= 0 and
(lcodes_err < 0 or nlen ~= (lcodes_huffman_bitlen_counts[0] or 0) +
(lcodes_huffman_bitlen_counts[1] or 0))) then return -7 end
local dcodes_err, dcodes_huffman_bitlen_counts, dcodes_huffman_symbols,
dcodes_huffman_min_bitlen = GetHuffmanForDecode(dcodes_huffman_bitlens,
ndist - 1, 15)
-- dynamic block code description: invalid distance code lengths,
-- Incomplete code ok only for single length 1 code
if (dcodes_err ~= 0 and
(dcodes_err < 0 or ndist ~= (dcodes_huffman_bitlen_counts[0] or 0) +
(dcodes_huffman_bitlen_counts[1] or 0))) then return -8 end
-- Build buffman table for literal/length codes
return DecodeUntilEndOfBlock(state, lcodes_huffman_bitlen_counts,
lcodes_huffman_symbols,
lcodes_huffman_min_bitlen,
dcodes_huffman_bitlen_counts,
dcodes_huffman_symbols, dcodes_huffman_min_bitlen)
end
-- Decompress a deflate stream
-- @param state: a decompression state
-- @return the decompressed string if succeeds. nil if fails.
local function Inflate(state)
local ReadBits = state.ReadBits
local is_last_block
while not is_last_block do
is_last_block = (ReadBits(1) == 1)
local block_type = ReadBits(2)
local status
if block_type == 0 then
status = DecompressStoreBlock(state)
elseif block_type == 1 then
status = DecompressFixBlock(state)
elseif block_type == 2 then
status = DecompressDynamicBlock(state)
else
return nil, -1 -- invalid block type (type == 3)
end
if status ~= 0 then return nil, status end
end
state.result_buffer[#state.result_buffer + 1] =
table_concat(state.buffer, "", 1, state.buffer_size)
local result = table_concat(state.result_buffer)
return result
end
-- @see LibDeflate:DecompressDeflate(str)
-- @see LibDeflate:DecompressDeflateWithDict(str, dictionary)
local function DecompressDeflateInternal(str, dictionary)
local state = CreateDecompressState(str, dictionary)
local result, status = Inflate(state)
if not result then return nil, status end
local bitlen_left = state.ReaderBitlenLeft()
local bytelen_left = (bitlen_left - bitlen_left % 8) / 8
return result, bytelen_left
end
-- @see LibDeflate:DecompressZlib(str)
-- @see LibDeflate:DecompressZlibWithDict(str)
local function DecompressZlibInternal(str, dictionary)
local state = CreateDecompressState(str, dictionary)
local ReadBits = state.ReadBits
local CMF = ReadBits(8)
if state.ReaderBitlenLeft() < 0 then
return nil, 2 -- available inflate data did not terminate
end
local CM = CMF % 16
local CINFO = (CMF - CM) / 16
if CM ~= 8 then
return nil, -12 -- invalid compression method
end
if CINFO > 7 then
return nil, -13 -- invalid window size
end
local FLG = ReadBits(8)
if state.ReaderBitlenLeft() < 0 then
return nil, 2 -- available inflate data did not terminate
end
if (CMF * 256 + FLG) % 31 ~= 0 then
return nil, -14 -- invalid header checksum
end
local FDIST = ((FLG - FLG % 32) / 32 % 2)
local FLEVEL = ((FLG - FLG % 64) / 64 % 4) -- luacheck: ignore FLEVEL
if FDIST == 1 then
if not dictionary then
return nil, -16 -- need dictonary, but dictionary is not provided.
end
local byte3 = ReadBits(8)
local byte2 = ReadBits(8)
local byte1 = ReadBits(8)
local byte0 = ReadBits(8)
local actual_adler32 = byte3 * 16777216 + byte2 * 65536 + byte1 * 256 +
byte0
if state.ReaderBitlenLeft() < 0 then
return nil, 2 -- available inflate data did not terminate
end
if not IsEqualAdler32(actual_adler32, dictionary.adler32) then
return nil, -17 -- dictionary adler32 does not match
end
end
local result, status = Inflate(state)
if not result then return nil, status end
state.SkipToByteBoundary()
local adler_byte0 = ReadBits(8)
local adler_byte1 = ReadBits(8)
local adler_byte2 = ReadBits(8)
local adler_byte3 = ReadBits(8)
if state.ReaderBitlenLeft() < 0 then
return nil, 2 -- available inflate data did not terminate
end
local adler32_expected = adler_byte0 * 16777216 + adler_byte1 * 65536 +
adler_byte2 * 256 + adler_byte3
local adler32_actual = LibDeflate:Adler32(result)
if not IsEqualAdler32(adler32_expected, adler32_actual) then
return nil, -15 -- Adler32 checksum does not match
end
local bitlen_left = state.ReaderBitlenLeft()
local bytelen_left = (bitlen_left - bitlen_left % 8) / 8
return result, bytelen_left
end
--- Decompress a raw deflate compressed data.
-- @param str [string] The data to be decompressed.
-- @return [string/nil] If the decompression succeeds, return the decompressed
-- data. If the decompression fails, return nil. You should check if this return
-- value is non-nil to know if the decompression succeeds.
-- @return [integer] If the decompression succeeds, return the number of
-- unprocessed bytes in the input compressed data. This return value is a
-- positive integer if the input data is a valid compressed data appended by an
-- arbitary non-empty string. This return value is 0 if the input data does not
-- contain any extra bytes.<br>
-- If the decompression fails (The first return value of this function is nil),
-- this return value is undefined.
-- @see LibDeflate:CompressDeflate
function LibDeflate:DecompressDeflate(str)
local arg_valid, arg_err = IsValidArguments(str)
if not arg_valid then
error(("Usage: LibDeflate:DecompressDeflate(str): " .. arg_err), 2)
end
return DecompressDeflateInternal(str)
end
--- Decompress a raw deflate compressed data with a preset dictionary.
-- @param str [string] The data to be decompressed.
-- @param dictionary [table] The preset dictionary used by
-- LibDeflate:CompressDeflateWithDict when the compressed data is produced.
-- Decompression and compression must use the same dictionary.
-- Otherwise wrong decompressed data could be produced without generating any
-- error.
-- @return [string/nil] If the decompression succeeds, return the decompressed
-- data. If the decompression fails, return nil. You should check if this return
-- value is non-nil to know if the decompression succeeds.
-- @return [integer] If the decompression succeeds, return the number of
-- unprocessed bytes in the input compressed data. This return value is a
-- positive integer if the input data is a valid compressed data appended by an
-- arbitary non-empty string. This return value is 0 if the input data does not
-- contain any extra bytes.<br>
-- If the decompression fails (The first return value of this function is nil),
-- this return value is undefined.
-- @see LibDeflate:CompressDeflateWithDict
function LibDeflate:DecompressDeflateWithDict(str, dictionary)
local arg_valid, arg_err = IsValidArguments(str, true, dictionary)
if not arg_valid then
error(("Usage: LibDeflate:DecompressDeflateWithDict(str, dictionary): " ..
arg_err), 2)
end
return DecompressDeflateInternal(str, dictionary)
end
--- Decompress a zlib compressed data.
-- @param str [string] The data to be decompressed
-- @return [string/nil] If the decompression succeeds, return the decompressed
-- data. If the decompression fails, return nil. You should check if this return
-- value is non-nil to know if the decompression succeeds.
-- @return [integer] If the decompression succeeds, return the number of
-- unprocessed bytes in the input compressed data. This return value is a
-- positive integer if the input data is a valid compressed data appended by an
-- arbitary non-empty string. This return value is 0 if the input data does not
-- contain any extra bytes.<br>
-- If the decompression fails (The first return value of this function is nil),
-- this return value is undefined.
-- @see LibDeflate:CompressZlib
function LibDeflate:DecompressZlib(str)
local arg_valid, arg_err = IsValidArguments(str)
if not arg_valid then
error(("Usage: LibDeflate:DecompressZlib(str): " .. arg_err), 2)
end
return DecompressZlibInternal(str)
end
--- Decompress a zlib compressed data with a preset dictionary.
-- @param str [string] The data to be decompressed
-- @param dictionary [table] The preset dictionary used by
-- LibDeflate:CompressDeflateWithDict when the compressed data is produced.
-- Decompression and compression must use the same dictionary.
-- Otherwise wrong decompressed data could be produced without generating any
-- error.
-- @return [string/nil] If the decompression succeeds, return the decompressed
-- data. If the decompression fails, return nil. You should check if this return
-- value is non-nil to know if the decompression succeeds.
-- @return [integer] If the decompression succeeds, return the number of
-- unprocessed bytes in the input compressed data. This return value is a
-- positive integer if the input data is a valid compressed data appended by an
-- arbitary non-empty string. This return value is 0 if the input data does not
-- contain any extra bytes.<br>
-- If the decompression fails (The first return value of this function is nil),
-- this return value is undefined.
-- @see LibDeflate:CompressZlibWithDict
function LibDeflate:DecompressZlibWithDict(str, dictionary)
local arg_valid, arg_err = IsValidArguments(str, true, dictionary)
if not arg_valid then
error(("Usage: LibDeflate:DecompressZlibWithDict(str, dictionary): " ..
arg_err), 2)
end
return DecompressZlibInternal(str, dictionary)
end
-- Calculate the huffman code of fixed block
do
_fix_block_literal_huffman_bitlen = {}
for sym = 0, 143 do _fix_block_literal_huffman_bitlen[sym] = 8 end
for sym = 144, 255 do _fix_block_literal_huffman_bitlen[sym] = 9 end
for sym = 256, 279 do _fix_block_literal_huffman_bitlen[sym] = 7 end
for sym = 280, 287 do _fix_block_literal_huffman_bitlen[sym] = 8 end
_fix_block_dist_huffman_bitlen = {}
for dist = 0, 31 do _fix_block_dist_huffman_bitlen[dist] = 5 end
local status
status, _fix_block_literal_huffman_bitlen_count, _fix_block_literal_huffman_to_deflate_code =
GetHuffmanForDecode(_fix_block_literal_huffman_bitlen, 287, 9)
assert(status == 0)
status, _fix_block_dist_huffman_bitlen_count, _fix_block_dist_huffman_to_deflate_code =
GetHuffmanForDecode(_fix_block_dist_huffman_bitlen, 31, 5)
assert(status == 0)
_fix_block_literal_huffman_code = GetHuffmanCodeFromBitlen(
_fix_block_literal_huffman_bitlen_count,
_fix_block_literal_huffman_bitlen, 287, 9)
_fix_block_dist_huffman_code = GetHuffmanCodeFromBitlen(
_fix_block_dist_huffman_bitlen_count,
_fix_block_dist_huffman_bitlen, 31, 5)
end
-- While the codec stuff is neat, it's unnecessary for ComputerCraft files
-- which can store and transmit data of any type with no restrictions on
-- content.
-- For test. Don't use the functions in this table for real application.
-- Stuffs in this table is subject to change.
-- Since you aren't supposed to use this stuff anyways, I'm just gonna comment
-- it out.
--[[LibDeflate.internals = {
LoadStringToTable = LoadStringToTable,
IsValidDictionary = IsValidDictionary,
IsEqualAdler32 = IsEqualAdler32,
_byte_to_6bit_char = _byte_to_6bit_char,
_6bit_to_byte = _6bit_to_byte,
InternalClearCache = InternalClearCache
}]]
-- Also removed the command line thing
return LibDeflate
Raw
LibDeflate_min.lua
--[[--
LibDeflate 1.0.2-release <br>
Pure Lua compressor and decompressor with high compression ratio using
DEFLATE/zlib format.
Based on the original by Haoqian He, pared down for ComputerCraft usage
by Robert "khuxkm/minerobber" Miles
]] --[[
zlib License
(C) 2018-2021 Haoqian He
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely, subject to the following restrictions:
1. The origin of this software must not be misrepresented; you must not
claim that you wrote the original software. If you use this software
in a product, an acknowledgment in the product documentation would be
appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be
misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
License History:
1. GNU General Public License Version 3 in v1.0.0 and earlier versions.
2. GNU Lesser General Public License Version 3 in v1.0.1
3. the zlib License since v1.0.2
Credits and Disclaimer:
This library rewrites the code from the algorithm
and the ideas of the following projects,
and uses their code to help to test the correctness of this library,
but their code is not included directly in the library itself.
Their original licenses shall be comply when used.
1. zlib, by Jean-loup Gailly (compression) and Mark Adler (decompression).
http://www.zlib.net/
Licensed under zlib License. http://www.zlib.net/zlib_license.html
For the compression algorithm.
2. puff, by Mark Adler. https://github.com/madler/zlib/tree/master/contrib/puff
Licensed under zlib License. http://www.zlib.net/zlib_license.html
For the decompression algorithm.
3. LibCompress, by jjsheets and Galmok of European Stormrage (Horde)
https://www.wowace.com/projects/libcompress
Licensed under GPLv2.
https://www.gnu.org/licenses/old-licenses/gpl-2.0.html
For the code to create customized codec.
4. WeakAuras2,
https://github.com/WeakAuras/WeakAuras2
Licensed under GPLv2.
For the 6bit encoding and decoding.
]]
local JtAjijkG
do local YKA7cU="1.0.2-release"
local mCsewfX="LibDeflate "..YKA7cU..
" Copyright (C) 2018-2021 Haoqian He.".." Modifications (c) 2022 minerobber"..
" Licensed under the zlib License"JtAjijkG={}JtAjijkG._VERSION=YKA7cU;JtAjijkG._COPYRIGHT=mCsewfX end;local s=assert;local YAtG_LV3=error;local LfEJbh_=pairs;local JD=string.byte;local u=string.char
local pzDMZwG=string.find;local XPoQB=string.gsub;local XxJ=string.sub;local o5sms=table.concat
local JQi1jg=table.sort;local wVzn=tostring;local pE=type;local RSjapQ={}local QJf={}local zC={}local pfZ3SPy_={}local pDNa2ox6={}local Do6yo7nm={}
local y06X3k={}local ivnJjrA={}local d3fMjkg={}
local el={3,4,5,6,7,8,9,10,11,13,15,17,19,23,27,31,35,43,51,59,67,83,99,115,131,163,195,227,258}
local Wu_uIt={0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0}
local w={[0]=1,2,3,4,5,7,9,13,17,25,33,49,65,97,129,193,257,385,513,769,1025,1537,2049,3073,4097,6145,8193,12289,16385,24577}
local sgeP={[0]=0,0,0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13}local CM={16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15}local Qlmlet
local _;local RkGFh6;local hw18;local nvCiFt7r;local xSebv5Jc;local mMp;local rDtVf;for yY=0,255 do QJf[yY]=u(yY)end
do local Xf=1;for UlFdiZ7v=0,32
do RSjapQ[UlFdiZ7v]=Xf;Xf=Xf*2 end end
for U=1,9 do zC[U]={}
for wFeA=0,RSjapQ[U+1]-1 do local JQgI=0;local N=wFeA;for fs52REi=1,U do JQgI=JQgI-JQgI%2+
((
(JQgI%2 ==1)or(N%2)==1)and 1 or 0)N=(N-N%2)/2;JQgI=
JQgI*2 end;zC[U][wFeA]=(JQgI-
JQgI%2)/2 end end
do local PUNkgaiM=18;local s6FbB=16;local X=265;local dc61=1
for aguhyl=3,258 do
if aguhyl<=10 then
pfZ3SPy_[aguhyl]=aguhyl+254;Do6yo7nm[aguhyl]=0 elseif aguhyl==258 then pfZ3SPy_[aguhyl]=285
Do6yo7nm[aguhyl]=0 else if aguhyl>PUNkgaiM then PUNkgaiM=PUNkgaiM+s6FbB;s6FbB=s6FbB*2;X=X+4
dc61=dc61+1 end
local p=aguhyl-PUNkgaiM-1+s6FbB/2;pfZ3SPy_[aguhyl]=
(p- (p% (s6FbB/8)))/ (s6FbB/8)+X;Do6yo7nm[aguhyl]=dc61;pDNa2ox6[aguhyl]=
p% (s6FbB/8)end end end
do y06X3k[1]=0;y06X3k[2]=1;d3fMjkg[1]=0;d3fMjkg[2]=0;local gOPDv=3;local aSdZU3=4
local YKDL=2;local oFyb6OLp=0
for oGdh_mv=3,256 do if oGdh_mv>aSdZU3 then gOPDv=gOPDv*2;aSdZU3=aSdZU3*2;YKDL=YKDL+2;oFyb6OLp=
oFyb6OLp+1 end
y06X3k[oGdh_mv]=(
oGdh_mv<=gOPDv)and YKDL or(YKDL+1)
d3fMjkg[oGdh_mv]=(oFyb6OLp<0)and 0 or oFyb6OLp;if aSdZU3 >=8 then
ivnJjrA[oGdh_mv]=(oGdh_mv-aSdZU3/2-1)% (aSdZU3/4)end end end
function JtAjijkG:Adler32(WjvvK)if pE(WjvvK)~="string"then
YAtG_LV3(("Usage: LibDeflate:Adler32(str):".." 'str' - string expected got '%s'."):format(pE(WjvvK)),2)end
local TASVwBgU=#WjvvK;local KjUncMB=1;local XkT=1;local c3dr=0
while KjUncMB<=TASVwBgU-15 do
local NGH,tIc,MD2O,HQ,cng,lE,nI2F0id,N4aMD_P,pCi,NzeoQJ,AwGfFV,wCRY,d0uKSVw1,lNOqUk8,YAnZNei,h8YWR44E=JD(WjvvK,KjUncMB,KjUncMB+15)
c3dr=
(
c3dr+16*XkT+16*NGH+15*tIc+14*MD2O+13*HQ+12*cng+11*lE+10*nI2F0id+9*N4aMD_P+8*pCi+7*NzeoQJ+6*AwGfFV+5*wCRY+4*d0uKSVw1+3*lNOqUk8+2*
YAnZNei+h8YWR44E)%65521
XkT=
(
XkT+NGH+tIc+MD2O+HQ+cng+lE+nI2F0id+N4aMD_P+pCi+NzeoQJ+AwGfFV+wCRY+d0uKSVw1+lNOqUk8+YAnZNei+h8YWR44E)%65521;KjUncMB=KjUncMB+16 end;while(KjUncMB<=TASVwBgU)do local VF=JD(WjvvK,KjUncMB,KjUncMB)XkT=
(XkT+VF)%65521;c3dr=(c3dr+XkT)%65521
KjUncMB=KjUncMB+1 end;return
(c3dr*65536+XkT)%4294967296 end;local function vj(fTrMe,ypDndT8)
return(fTrMe%4294967296)== (ypDndT8%4294967296)end
function JtAjijkG:CreateDictionary(MV65,Y3D66Ym9,q)
if
pE(MV65)~="string"then
YAtG_LV3(("Usage: LibDeflate:CreateDictionary(str, strlen, adler32):".." 'str' - string expected got '%s'."):format(pE(MV65)),2)end
if pE(Y3D66Ym9)~="number"then
YAtG_LV3(("Usage: LibDeflate:CreateDictionary(str, strlen, adler32):"..
" 'strlen' - number expected got '%s'."):format(pE(Y3D66Ym9)),2)end
if pE(q)~="number"then
YAtG_LV3(("Usage: LibDeflate:CreateDictionary(str, strlen, adler32):".." 'adler32' - number expected got '%s'."):format(pE(q)),2)end
if Y3D66Ym9 ~=#MV65 then
YAtG_LV3(("Usage: LibDeflate:CreateDictionary(str, strlen, adler32):"..
" 'strlen' does not match the actual length of 'str'."..
" 'strlen': %u, '#str': %u .".." Please check if 'str' is modified unintentionally."):format(Y3D66Ym9,
#MV65))end;if Y3D66Ym9 ==0 then
YAtG_LV3(("Usage: LibDeflate:CreateDictionary(str, strlen, adler32):".." 'str' - Empty string is not allowed."),2)end
if Y3D66Ym9 >
32768 then
YAtG_LV3(("Usage: LibDeflate:CreateDictionary(str, strlen, adler32):".." 'str' - string longer than 32768 bytes is not allowed."..
" Got %d bytes."):format(Y3D66Ym9),2)end;local PhJ=self:Adler32(MV65)
if not vj(q,PhJ)then
YAtG_LV3((
"Usage: LibDeflate:CreateDictionary(str, strlen, adler32):"..
" 'adler32' does not match the actual adler32 of 'str'."..
" 'adler32': %u, 'Adler32(str)': %u .".." Please check if 'str' is modified unintentionally."):format(q,PhJ))end;local h={}h.adler32=q;h.hash_tables={}h.string_table={}h.strlen=Y3D66Ym9
local j2K=h.string_table;local r8hgwQ=h.hash_tables;j2K[1]=JD(MV65,1,1)j2K[2]=JD(MV65,2,2)
if
Y3D66Ym9 >=3 then local _6U=1;local GLSzBQs=j2K[1]*256+j2K[2]
while _6U<=Y3D66Ym9-2-3 do local c,xg,Id2KoP_G,Y2or=JD(MV65,
_6U+2,_6U+5)j2K[_6U+2]=c
j2K[_6U+3]=xg;j2K[_6U+4]=Id2KoP_G;j2K[_6U+5]=Y2or;GLSzBQs=(GLSzBQs*256+c)%
16777216;local zN8ASHV5=r8hgwQ[GLSzBQs]if not zN8ASHV5 then
zN8ASHV5={}r8hgwQ[GLSzBQs]=zN8ASHV5 end;zN8ASHV5[#zN8ASHV5+1]=
_6U-Y3D66Ym9;_6U=_6U+1
GLSzBQs=(GLSzBQs*256+xg)%16777216;zN8ASHV5=r8hgwQ[GLSzBQs]if not zN8ASHV5 then zN8ASHV5={}
r8hgwQ[GLSzBQs]=zN8ASHV5 end
zN8ASHV5[#zN8ASHV5+1]=_6U-Y3D66Ym9;_6U=_6U+1
GLSzBQs=(GLSzBQs*256+Id2KoP_G)%16777216;zN8ASHV5=r8hgwQ[GLSzBQs]if not zN8ASHV5 then zN8ASHV5={}
r8hgwQ[GLSzBQs]=zN8ASHV5 end
zN8ASHV5[#zN8ASHV5+1]=_6U-Y3D66Ym9;_6U=_6U+1
GLSzBQs=(GLSzBQs*256+Y2or)%16777216;zN8ASHV5=r8hgwQ[GLSzBQs]if not zN8ASHV5 then zN8ASHV5={}
r8hgwQ[GLSzBQs]=zN8ASHV5 end
zN8ASHV5[#zN8ASHV5+1]=_6U-Y3D66Ym9;_6U=_6U+1 end
while _6U<=Y3D66Ym9-2 do local iju=JD(MV65,_6U+2)j2K[_6U+2]=iju;GLSzBQs=(
GLSzBQs*256+iju)%16777216
local XsWgh=r8hgwQ[GLSzBQs]if not XsWgh then XsWgh={}r8hgwQ[GLSzBQs]=XsWgh end;XsWgh[#XsWgh+
1]=_6U-Y3D66Ym9;_6U=_6U+1 end end;return h end
local function z(l4Hdz)
if pE(l4Hdz)~="table"then return false,
("'dictionary' - table expected got '%s'."):format(pE(l4Hdz))end
if
pE(l4Hdz.adler32)~="number"or
pE(l4Hdz.string_table)~="table"or pE(l4Hdz.strlen)~="number"or l4Hdz.strlen<=0 or
l4Hdz.strlen>32768 or l4Hdz.strlen~=#l4Hdz.string_table or pE(l4Hdz.hash_tables)~="table"then return false,
("'dictionary' - corrupted dictionary."):format(pE(l4Hdz))end;return true,""end
local Zg={[0]={false,nil,0,0,0},[1]={false,nil,4,8,4},[2]={false,nil,5,18,8},[3]={false,nil,6,32,32},[4]={true,4,4,16,16},[5]={true,8,16,32,32},[6]={true,8,16,128,128},[7]={true,8,32,128,256},[8]={true,32,128,258,1024},[9]={true,32,258,258,4096}}
local function ykRppH(NSXCgSH,Wq,SbOQ,IiuHGo,cGqxtYr)
if pE(NSXCgSH)~="string"then return false,
("'str' - string expected got '%s'."):format(pE(NSXCgSH))end
if Wq then local bgJFKeeZ,yu9fg0nN=z(SbOQ)if not bgJFKeeZ then return false,yu9fg0nN end end
if IiuHGo then local wgx=pE(cGqxtYr)
if wgx~="nil"and wgx~="table"then return false,
("'configs' - nil or table expected got '%s'."):format(pE(cGqxtYr))end
if wgx=="table"then
for zlU7X,t in LfEJbh_(cGqxtYr)do
if zlU7X~="level"and zlU7X~="strategy"then return false,
("'configs' - unsupported table key in the configs: '%s'."):format(zlU7X)elseif
zlU7X=="level"and not Zg[t]then return false,
("'configs' - unsupported 'level': %s."):format(wVzn(t))elseif
zlU7X=="strategy"and t~="fixed"and t~="huffman_only"and t~="dynamic"then return false,
("'configs' - unsupported 'strategy': '%s'."):format(wVzn(t))end end end end;return true,""end;local WQ6=0;local y36Aetn=1;local iPL3B4cr=2;local GI2hz6SK=3
local function Oh()local f6qbO=0;local kk=0;local QrubIAv=0;local bLHDW=0;local YjFd7b={}
local jZgPYb={}
local function zN2(OWJ,WtalJw)kk=kk+OWJ*RSjapQ[QrubIAv]
QrubIAv=QrubIAv+WtalJw;bLHDW=bLHDW+WtalJw
if QrubIAv>=32 then f6qbO=f6qbO+1
YjFd7b[f6qbO]=QJf[kk%256]..QJf[((
kk-kk%256)/256%256)]..
QJf[(
(kk-kk%65536)/65536%256)]..QJf[(
(kk-kk%16777216)/16777216%256)]local JYrf2=RSjapQ[32-QrubIAv+WtalJw]kk=
(OWJ-OWJ%JYrf2)/JYrf2;QrubIAv=QrubIAv-32 end end
local function IN69pa5(KHDOUlRY)for I0JvPpn=1,QrubIAv,8 do f6qbO=f6qbO+1;YjFd7b[f6qbO]=u(kk%256)
kk=(kk-kk%256)/256 end;QrubIAv=0;f6qbO=f6qbO+1
YjFd7b[f6qbO]=KHDOUlRY;bLHDW=bLHDW+#KHDOUlRY*8 end
local function U(Ce4ZE)if Ce4ZE==GI2hz6SK then return bLHDW end
if
Ce4ZE==y36Aetn or Ce4ZE==iPL3B4cr then local lB=(8-QrubIAv%8)%8
if QrubIAv>0 then kk=kk-RSjapQ[QrubIAv]+RSjapQ[
QrubIAv+lB]
for byE=1,QrubIAv,8 do
f6qbO=f6qbO+1;YjFd7b[f6qbO]=QJf[kk%256]kk=(kk-kk%256)/256 end;kk=0;QrubIAv=0 end;if Ce4ZE==iPL3B4cr then bLHDW=bLHDW+lB;return bLHDW end end;local OVx_mN=o5sms(YjFd7b)YjFd7b={}f6qbO=0
jZgPYb[#jZgPYb+1]=OVx_mN
if Ce4ZE==WQ6 then return bLHDW else return bLHDW,o5sms(jZgPYb)end end;return zN2,IN69pa5,U end
local function PG(bITCI,K,F5dtVpnN)F5dtVpnN=F5dtVpnN+1;bITCI[F5dtVpnN]=K;local kxeBp=K[1]local a=F5dtVpnN;local kQ=
(a-a%2)/2
while(kQ>=1 and bITCI[kQ][1]>kxeBp)do
local EE9LAE=bITCI[kQ]bITCI[kQ]=K;bITCI[a]=EE9LAE;a=kQ;kQ=(kQ-kQ%2)/2 end end
local function n(iVx,eg)local AQviNt=iVx[1]local T6=iVx[eg]local NviN0i=T6[1]iVx[1]=T6;iVx[eg]=AQviNt
eg=eg-1;local BlMQce=1;local o=BlMQce*2;local dpRE=o+1
while(o<=eg)do local fEiXwWq=iVx[o]
if(dpRE<=eg and
iVx[dpRE][1]<fEiXwWq[1])then
local r3JzMga6=iVx[dpRE]if r3JzMga6[1]<NviN0i then iVx[dpRE]=T6;iVx[BlMQce]=r3JzMga6;BlMQce=dpRE;o=BlMQce*
2;dpRE=o+1 else break end else if
fEiXwWq[1]<NviN0i then iVx[o]=T6;iVx[BlMQce]=fEiXwWq;BlMQce=o;o=BlMQce*2;dpRE=o+1 else
break end end end;return AQviNt end
local function O(Tuyw,FYLcr2nu,ioS69,AiP)local S2jwpoi=0;local _WX9u={}local u0riyU={}
for U=1,AiP do S2jwpoi=
(S2jwpoi+ (Tuyw[U-1]or 0))*2;_WX9u[U]=S2jwpoi end
for H=0,ioS69 do local WNph=FYLcr2nu[H]
if WNph then S2jwpoi=_WX9u[WNph]
_WX9u[WNph]=S2jwpoi+1
if WNph<=9 then u0riyU[H]=zC[WNph][S2jwpoi]else local ytF=0
for d=1,WNph do ytF=ytF-ytF%2+
((
(ytF%2 ==1)or(S2jwpoi%2)==1)and 1 or 0)S2jwpoi=
(S2jwpoi-S2jwpoi%2)/2;ytF=ytF*2 end;u0riyU[H]=(ytF-ytF%2)/2 end end end;return u0riyU end
local function N5UjTN(gRm,LPX0)return gRm[1]<LPX0[1]or
(gRm[1]==LPX0[1]and gRm[2]<LPX0[2])end
local function qLH5(g,_l,qao)local ipUPIzc;local N8=-1;local Gzk={}local J7nsK={}local dXbd={}local vQj={}local sVBxyy={}local N9d=0;for S7,bJtvRSR in LfEJbh_(g)do
N9d=N9d+1;Gzk[N9d]={bJtvRSR,S7}end
if(N9d==0)then
return{},{},-1 elseif(N9d==1)then local aBhZK5=Gzk[1][2]dXbd[aBhZK5]=1;vQj[aBhZK5]=0
return dXbd,vQj,aBhZK5 else JQi1jg(Gzk,N5UjTN)ipUPIzc=N9d
for UYQF=1,ipUPIzc do J7nsK[UYQF]=Gzk[UYQF]end
while(ipUPIzc>1)do local WXx=n(J7nsK,ipUPIzc)ipUPIzc=ipUPIzc-1
local W4EuxJXi=n(J7nsK,ipUPIzc)ipUPIzc=ipUPIzc-1
local BlYNd61h={WXx[1]+W4EuxJXi[1],-1,WXx,W4EuxJXi}PG(J7nsK,BlYNd61h,ipUPIzc)ipUPIzc=ipUPIzc+1 end;local Jz8JUscj=0;local OtGmbAgE={J7nsK[1],0,0,0}local oU_r=1;local n_lv=1;J7nsK[1][1]=0
while(
n_lv<=oU_r)do local XDPndG=OtGmbAgE[n_lv]local sJYFQIP4=XDPndG[1]
local Ogq0S2=XDPndG[2]local n8Cw3SR=XDPndG[3]local GJqd7gt=XDPndG[4]if n8Cw3SR then oU_r=oU_r+1
OtGmbAgE[oU_r]=n8Cw3SR;n8Cw3SR[1]=sJYFQIP4+1 end
if GJqd7gt then
oU_r=oU_r+1;OtGmbAgE[oU_r]=GJqd7gt;GJqd7gt[1]=sJYFQIP4+1 end;n_lv=n_lv+1
if(sJYFQIP4 >_l)then Jz8JUscj=Jz8JUscj+1;sJYFQIP4=_l end;if Ogq0S2 >=0 then dXbd[Ogq0S2]=sJYFQIP4
N8=(Ogq0S2 >N8)and Ogq0S2 or N8
sVBxyy[sJYFQIP4]=(sVBxyy[sJYFQIP4]or 0)+1 end end
if(Jz8JUscj>0)then
repeat local slE5aDm2=_l-1;while
((sVBxyy[slE5aDm2]or 0)==0)do slE5aDm2=slE5aDm2-1 end;sVBxyy[slE5aDm2]=
sVBxyy[slE5aDm2]-1;sVBxyy[slE5aDm2+1]=
(sVBxyy[slE5aDm2+1]or 0)+2;sVBxyy[_l]=sVBxyy[_l]-1;Jz8JUscj=
Jz8JUscj-2 until(Jz8JUscj<=0)n_lv=1;for aL_g=_l,1,-1 do local IMUI10L=sVBxyy[aL_g]or 0
while(IMUI10L>0)do
local vPA=Gzk[n_lv][2]dXbd[vPA]=aL_g;IMUI10L=IMUI10L-1;n_lv=n_lv+1 end end end;vQj=O(sVBxyy,dXbd,qao,_l)return dXbd,vQj,N8 end end
local function tE(pUXZ6G4,mk,OeQex1U4,i0cV9)local EGD=0;local VWiGCreH={}local B_kkL={}local uEO6Y=0;local i_053JPY={}local l=nil;local UK=0;i0cV9=(i0cV9 <0)and 0 or
i0cV9;local NzaICo=mk+i0cV9+1
for k1X83nYm=0,NzaICo+1 do
local xxzxfj=
(k1X83nYm<=mk)and(pUXZ6G4[k1X83nYm]or 0)or(
(k1X83nYm<=NzaICo)and(OeQex1U4[k1X83nYm-mk-1]or 0)or nil)
if xxzxfj==l then UK=UK+1
if xxzxfj~=0 and UK==6 then EGD=EGD+1;VWiGCreH[EGD]=16
uEO6Y=uEO6Y+1;i_053JPY[uEO6Y]=3
B_kkL[16]=(B_kkL[16]or 0)+1;UK=0 elseif xxzxfj==0 and UK==138 then EGD=EGD+1;VWiGCreH[EGD]=18;uEO6Y=uEO6Y+1
i_053JPY[uEO6Y]=127;B_kkL[18]=(B_kkL[18]or 0)+1;UK=0 end else
if UK==1 then EGD=EGD+1;VWiGCreH[EGD]=l
B_kkL[l]=(B_kkL[l]or 0)+1 elseif UK==2 then EGD=EGD+1;VWiGCreH[EGD]=l;EGD=EGD+1;VWiGCreH[EGD]=l;B_kkL[l]=(
B_kkL[l]or 0)+2 elseif UK>=3 then EGD=EGD+1;local _ad1m4I=(l~=0)and 16 or(
UK<=10 and 17 or 18)
VWiGCreH[EGD]=_ad1m4I
B_kkL[_ad1m4I]=(B_kkL[_ad1m4I]or 0)+1;uEO6Y=uEO6Y+1
i_053JPY[uEO6Y]=(UK<=10)and(UK-3)or(UK-11)end;l=xxzxfj
if xxzxfj and xxzxfj~=0 then EGD=EGD+1;VWiGCreH[EGD]=xxzxfj;B_kkL[xxzxfj]=(
B_kkL[xxzxfj]or 0)+1;UK=0 else UK=1 end end end;return VWiGCreH,i_053JPY,B_kkL end
local function VcV0EuD(H1QsS,rIMx,TiA,Y51P,ichL)local NOK=TiA-ichL
while NOK<=Y51P-15-ichL do
rIMx[NOK],rIMx[NOK+1],rIMx[NOK+2],rIMx[
NOK+3],rIMx[NOK+4],rIMx[NOK+5],rIMx[NOK+6],rIMx[NOK+7],rIMx[NOK+8],rIMx[NOK+9],rIMx[
NOK+10],rIMx[NOK+11],rIMx[NOK+12],rIMx[NOK+13],rIMx[NOK+14],rIMx[NOK+15]=JD(H1QsS,
NOK+ichL,NOK+15+ichL)NOK=NOK+16 end;while(NOK<=Y51P-ichL)do
rIMx[NOK]=JD(H1QsS,NOK+ichL,NOK+ichL)NOK=NOK+1 end;return rIMx end
local function pX4gCR(Alv,YeLO2,CkrmO,ooovsSJe,s5IsD,KvYEVoXt,VWWD_P)local zsMuNkv=Zg[Alv]
local aXxi,Q18a7QTy,K5Rp6,GTIA,gdPUe=zsMuNkv[1],zsMuNkv[2],zsMuNkv[3],zsMuNkv[4],zsMuNkv[5]local _bxEn=(not aXxi)and K5Rp6 or 2147483646;local pcN_ceXY=(gdPUe-
gdPUe%4/4)local _P;local rq;local mo;local I=0
if VWWD_P then
rq=VWWD_P.hash_tables;mo=VWWD_P.string_table;I=VWWD_P.strlen;s(ooovsSJe==1)if
s5IsD>=ooovsSJe and I>=2 then
_P=mo[I-1]*65536+mo[I]*256+YeLO2[1]local r3=CkrmO[_P]if not r3 then r3={}CkrmO[_P]=r3 end
r3[#r3+1]=-1 end
if s5IsD>=
ooovsSJe+1 and I>=1 then _P=mo[I]*65536+YeLO2[1]*256+
YeLO2[2]local p=CkrmO[_P]
if not p then p={}CkrmO[_P]=p end;p[#p+1]=0 end end;local RAAJAsR=I+3
_P=
(YeLO2[ooovsSJe-KvYEVoXt]or 0)*256+ (YeLO2[ooovsSJe+1-KvYEVoXt]or 0)local c1pjj7={}local BMv=0;local NQh8={}local P={}local bkTe=0;local ohmPbyDd={}local D={}local DfDLWkT=0;local MTU8HP4d={}
local hIM_cG0i=0;local jD=false;local me;local sgU5HAMG;local FDydY=0;local PEZ_=0;local c=ooovsSJe
local ElbTbcZG=s5IsD+ (aXxi and 1 or 0)
while(c<=ElbTbcZG)do local UiVYRok=c-KvYEVoXt;local jvPsY9=KvYEVoXt-3;me=FDydY
sgU5HAMG=PEZ_;FDydY=0;_P=
(_P*256+ (YeLO2[UiVYRok+2]or 0))%16777216;local tEBmuypm;local hW
local iOcgdUx=CkrmO[_P]local kCwLIk
if not iOcgdUx then kCwLIk=0;iOcgdUx={}CkrmO[_P]=iOcgdUx;if rq then hW=rq[_P]tEBmuypm=
hW and#hW or 0 else tEBmuypm=0 end else
kCwLIk=#iOcgdUx;hW=iOcgdUx;tEBmuypm=kCwLIk end;if c<=s5IsD then iOcgdUx[kCwLIk+1]=c end
if
(tEBmuypm>0 and
c+2 <=s5IsD and(not aXxi or me<K5Rp6))then
local _l=(aXxi and me>=Q18a7QTy)and pcN_ceXY or gdPUe;local rjQ=s5IsD-c;rjQ=(rjQ>=257)and 257 or rjQ
rjQ=rjQ+UiVYRok;local Euo0=UiVYRok+3
while tEBmuypm>=1 and _l>0 do local LIV=hW[tEBmuypm]if
c-LIV>32768 then break end
if LIV<c then local vydlAbZ3=Euo0
if LIV>=-257 then local mKLU=LIV-jvPsY9
while
(vydlAbZ3 <=rjQ and
YeLO2[mKLU]==YeLO2[vydlAbZ3])do vydlAbZ3=vydlAbZ3+1;mKLU=mKLU+1 end else local Him=RAAJAsR+LIV
while
(vydlAbZ3 <=rjQ and mo[Him]==YeLO2[vydlAbZ3])do vydlAbZ3=vydlAbZ3+1;Him=Him+1 end end;local BXxv5z=vydlAbZ3-UiVYRok
if BXxv5z>FDydY then FDydY=BXxv5z;PEZ_=c-LIV end;if FDydY>=GTIA then break end end;tEBmuypm=tEBmuypm-1;_l=_l-1;if tEBmuypm==0 and LIV>0 and rq then
hW=rq[_P]tEBmuypm=hW and#hW or 0 end end end;if not aXxi then me,sgU5HAMG=FDydY,PEZ_ end
if
(
(not aXxi or jD)and(me>3 or(
me==3 and sgU5HAMG<4096))and FDydY<=me)then local cPDhu=pfZ3SPy_[me]local UQnOS=Do6yo7nm[me]local tRWU,X2Zy_nb,ITtw3N7E
if sgU5HAMG<=256 then
tRWU=y06X3k[sgU5HAMG]ITtw3N7E=ivnJjrA[sgU5HAMG]X2Zy_nb=d3fMjkg[sgU5HAMG]else tRWU=16
X2Zy_nb=7;local yozOp=384;local wxU=512
while true do
if sgU5HAMG<=yozOp then ITtw3N7E=
(sgU5HAMG- (wxU/2)-1)% (wxU/4)break elseif sgU5HAMG<=wxU then ITtw3N7E=(
sgU5HAMG- (wxU/2)-1)% (wxU/4)
tRWU=tRWU+1;break else tRWU=tRWU+2;X2Zy_nb=X2Zy_nb+1;yozOp=yozOp*2;wxU=wxU*2 end end end;BMv=BMv+1;c1pjj7[BMv]=cPDhu
NQh8[cPDhu]=(NQh8[cPDhu]or 0)+1;bkTe=bkTe+1;P[bkTe]=tRWU
ohmPbyDd[tRWU]=(ohmPbyDd[tRWU]or 0)+1
if UQnOS>0 then local kOmS5sy=pDNa2ox6[me]DfDLWkT=DfDLWkT+1;D[DfDLWkT]=kOmS5sy end
if X2Zy_nb>0 then hIM_cG0i=hIM_cG0i+1;MTU8HP4d[hIM_cG0i]=ITtw3N7E end
for CLSdD=c+1,c+me- (aXxi and 2 or 1)do
_P=(_P*256+ (
YeLO2[CLSdD-KvYEVoXt+2]or 0))%16777216
if me<=_bxEn then iOcgdUx=CkrmO[_P]
if not iOcgdUx then iOcgdUx={}CkrmO[_P]=iOcgdUx end;iOcgdUx[#iOcgdUx+1]=CLSdD end end;c=c+me- (aXxi and 1 or 0)jD=false elseif
(not aXxi)or jD then
local Fh=YeLO2[aXxi and(UiVYRok-1)or UiVYRok]BMv=BMv+1;c1pjj7[BMv]=Fh
NQh8[Fh]=(NQh8[Fh]or 0)+1;c=c+1 else jD=true;c=c+1 end end;BMv=BMv+1;c1pjj7[BMv]=256
NQh8[256]=(NQh8[256]or 0)+1;return c1pjj7,D,NQh8,P,MTU8HP4d,ohmPbyDd end
local function gad4ZcL(IlAPA,jLKMpQuK)local sUQpby,mbA,_qPhpaFx=qLH5(IlAPA,15,285)
local zex,pPGcdu,rjp=qLH5(jLKMpQuK,15,29)local cT2z,zke1tWps,gRFA=tE(sUQpby,_qPhpaFx,zex,rjp)
local jX9a0tJX,YFy4TGc=qLH5(gRFA,7,18)local YjpbYkCb=0
for WpOZ=1,19 do local fD2289=CM[WpOZ]local folfO=jX9a0tJX[fD2289]or 0;if
folfO~=0 then YjpbYkCb=WpOZ end end;YjpbYkCb=YjpbYkCb-4;local L1p7luJ=_qPhpaFx+1-257;local eH=rjp+1-1;if eH<0 then
eH=0 end
return L1p7luJ,eH,YjpbYkCb,jX9a0tJX,YFy4TGc,cT2z,zke1tWps,sUQpby,mbA,zex,pPGcdu end
local function dk(vtsK,E1p4Mv,IHap,rDvV,RX1L2q,bCBtWguf,q)local e1sXUN4f=17;e1sXUN4f=e1sXUN4f+ (IHap+4)*3
for VP=1,#RX1L2q do
local IQwqq=RX1L2q[VP]e1sXUN4f=e1sXUN4f+rDvV[IQwqq]
if IQwqq>=16 then e1sXUN4f=e1sXUN4f+
(
(IQwqq==16)and 2 or(IQwqq==17 and 3 or 7))end end;local x=0
for Xcc4=1,#vtsK do local fqw5=vtsK[Xcc4]local qnVfOeRE=bCBtWguf[fqw5]
e1sXUN4f=e1sXUN4f+qnVfOeRE
if fqw5 >256 then x=x+1;if fqw5 >264 and fqw5 <285 then local qeJtG=Wu_uIt[fqw5-256]e1sXUN4f=
e1sXUN4f+qeJtG end
local YIiSKsxK=E1p4Mv[x]local Ua=q[YIiSKsxK]e1sXUN4f=e1sXUN4f+Ua;if YIiSKsxK>3 then local pdpNgBcZ=
(YIiSKsxK-YIiSKsxK%2)/2-1
e1sXUN4f=e1sXUN4f+pdpNgBcZ end end end;return e1sXUN4f end
local function E(wV,rLd,z8oF,DB6A7N,VhYX,Ha7ErH,rjU95v,sxBl,m,nD4LhX6z,iN,Lq,s9tW,R61K,Jf4os,a4xc,e)wV(rLd and 1 or 0,1)wV(2,2)wV(rjU95v,5)wV(sxBl,5)
wV(m,4)for Yw8Yxix=1,m+4 do local iVoXG=CM[Yw8Yxix]local JL0I04c=nD4LhX6z[iVoXG]or 0
wV(JL0I04c,3)end;local la5=1
for En6r_K97=1,#Lq do
local T4AA=Lq[En6r_K97]wV(iN[T4AA],nD4LhX6z[T4AA])if T4AA>=16 then local VnuCKTdu=s9tW[la5]
wV(VnuCKTdu,(
T4AA==16)and 2 or(T4AA==17 and 3 or 7))la5=la5+1 end end;local i=0;local R=0;local xWVu=0
for XnNgn=1,#z8oF do local H1JD=z8oF[XnNgn]local gEEa9I=Jf4os[H1JD]
local ULLLDUm=R61K[H1JD]wV(gEEa9I,ULLLDUm)
if H1JD>256 then i=i+1
if H1JD>264 and H1JD<285 then R=R+1
local YWPfQKb2=DB6A7N[R]local r=Wu_uIt[H1JD-256]wV(YWPfQKb2,r)end;local e4F3=VhYX[i]local GsfNt7=e[e4F3]local fF0=a4xc[e4F3]wV(GsfNt7,fF0)if
e4F3 >3 then xWVu=xWVu+1;local OS0Zp3i=Ha7ErH[xWVu]
local BK=(e4F3-e4F3%2)/2-1;wV(OS0Zp3i,BK)end end end end
local function OO(Idjbe70,B)local nDjt=3;local NVWt=0
for efuUGMh=1,#Idjbe70 do local p4nNp=Idjbe70[efuUGMh]local VW=RkGFh6[p4nNp]nDjt=
nDjt+VW
if p4nNp>256 then NVWt=NVWt+1;if p4nNp>264 and p4nNp<285 then
local V=Wu_uIt[p4nNp-256]nDjt=nDjt+V end;local Zt=B[NVWt]
nDjt=nDjt+5
if Zt>3 then local mzeTI=(Zt-Zt%2)/2-1;nDjt=nDjt+mzeTI end end end;return nDjt end
local function y(sy4J,ztJhP_u8,D,XIcl,ys,rMQ1um8)sy4J(ztJhP_u8 and 1 or 0,1)sy4J(1,2)local U2=0;local X=0
local zLtWO09=0
for Z=1,#D do local ZDICnKE=D[Z]local L=Qlmlet[ZDICnKE]local B58=RkGFh6[ZDICnKE]
sy4J(L,B58)
if ZDICnKE>256 then U2=U2+1
if ZDICnKE>264 and ZDICnKE<285 then X=X+1;local Pa=XIcl[X]local bmK=Wu_uIt[
ZDICnKE-256]sy4J(Pa,bmK)end;local PYVzrNl=ys[U2]local KTVmRC=nvCiFt7r[PYVzrNl]sy4J(KTVmRC,5)
if PYVzrNl>3 then zLtWO09=
zLtWO09+1;local OJPc3R=rMQ1um8[zLtWO09]local j=
(PYVzrNl-PYVzrNl%2)/2-1;sy4J(OJPc3R,j)end end end end
local function cR6rJlAl(vMgKnGj,M9K,Zeu)s(M9K-vMgKnGj+1 <=65535)local Q2_d=3;Zeu=Zeu+3;local W0iTcMIt=(8-
Zeu%8)%8;Q2_d=Q2_d+W0iTcMIt;Q2_d=Q2_d+32;Q2_d=Q2_d+ (M9K-
vMgKnGj+1)*8;return Q2_d end
local function M6ilzGJ(N,Hald6SO,Dq,y3Ur,GL70F7uL,lqANrrJA,WUFTXBy6)s(lqANrrJA-GL70F7uL+1 <=65535)N(
Dq and 1 or 0,1)N(0,2)WUFTXBy6=WUFTXBy6+3;local aEZf=
(8-WUFTXBy6%8)%8
if aEZf>0 then N(RSjapQ[aEZf]-1,aEZf)end;local QjQ_o=lqANrrJA-GL70F7uL+1;N(QjQ_o,16)local wDiq_=
(255-QjQ_o%256)+
(255- (QjQ_o-QjQ_o%256)/256)*256;N(wDiq_,16)
Hald6SO(y3Ur:sub(GL70F7uL,lqANrrJA))end
local function iW6CD(QYA5WJOY,yliV8,rjpKFl,YUGQovw,XZt7GyF,Zn3SC)local D4={}local crA9EKx={}local IcsJ=nil;local A;local Wp9xT;local P;local o0_XG8FI=YUGQovw(GI2hz6SK)
local jLsxpw=#XZt7GyF;local x;local AXNfV;local cX
if QYA5WJOY then if QYA5WJOY.level then AXNfV=QYA5WJOY.level end;if
QYA5WJOY.strategy then cX=QYA5WJOY.strategy end end;if not AXNfV then
if jLsxpw<2048 then AXNfV=7 elseif jLsxpw>65536 then AXNfV=3 else AXNfV=5 end end
while not IcsJ do
if not A then A=1
Wp9xT=64*1024-1;x=0 else A=Wp9xT+1;Wp9xT=Wp9xT+32*1024;x=A-32*1024-1 end;if Wp9xT>=jLsxpw then Wp9xT=jLsxpw;IcsJ=true else IcsJ=false end
local iyx,bxvn,mWYrzB,O7kX,Q4XSpdY,fzTyrQ9F;local fAumJ0i,i0,tZliF4,jlmopoj,R,uS_N6,o5SLRA,ztwXaCR,M2WtMgiq,FgfME,ylH9o;local CC4Kfjh;local k;local eUQ0x
if AXNfV~=0 then
VcV0EuD(XZt7GyF,D4,A,Wp9xT+3,x)
if A==1 and Zn3SC then local pYHkv=Zn3SC.string_table;local hxZHlgP=Zn3SC.strlen;for zct=0,
(-hxZHlgP+1)<-257 and-257 or(-hxZHlgP+1),-1 do D4[zct]=pYHkv[
hxZHlgP+zct]end end
if cX=="huffman_only"then iyx={}VcV0EuD(XZt7GyF,iyx,A,Wp9xT,A-1)bxvn={}
mWYrzB={}iyx[Wp9xT-A+2]=256
for WQk6Wkd=1,Wp9xT-A+2 do local t=iyx[WQk6Wkd]mWYrzB[t]=(
mWYrzB[t]or 0)+1 end;O7kX={}Q4XSpdY={}fzTyrQ9F={}else
iyx,bxvn,mWYrzB,O7kX,Q4XSpdY,fzTyrQ9F=pX4gCR(AXNfV,D4,crA9EKx,A,Wp9xT,x,Zn3SC)end
fAumJ0i,i0,tZliF4,jlmopoj,R,uS_N6,o5SLRA,ztwXaCR,M2WtMgiq,FgfME,ylH9o=gad4ZcL(mWYrzB,fzTyrQ9F)CC4Kfjh=dk(iyx,O7kX,tZliF4,jlmopoj,uS_N6,ztwXaCR,FgfME)
k=OO(iyx,O7kX)end;eUQ0x=cR6rJlAl(A,Wp9xT,o0_XG8FI)local r0OR=eUQ0x;r0OR=
(k and k<r0OR)and k or r0OR;r0OR=(CC4Kfjh and CC4Kfjh<r0OR)and
CC4Kfjh or r0OR
if AXNfV==0 or
(
cX~="fixed"and cX~="dynamic"and eUQ0x==r0OR)then
M6ilzGJ(yliV8,rjpKFl,IcsJ,XZt7GyF,A,Wp9xT,o0_XG8FI)o0_XG8FI=o0_XG8FI+eUQ0x elseif cX~="dynamic"and
(cX=="fixed"or k==r0OR)then y(yliV8,IcsJ,iyx,bxvn,O7kX,Q4XSpdY)o0_XG8FI=
o0_XG8FI+k elseif cX=="dynamic"or CC4Kfjh==r0OR then
E(yliV8,IcsJ,iyx,bxvn,O7kX,Q4XSpdY,fAumJ0i,i0,tZliF4,jlmopoj,R,uS_N6,o5SLRA,ztwXaCR,M2WtMgiq,FgfME,ylH9o)o0_XG8FI=o0_XG8FI+CC4Kfjh end;if IcsJ then P=YUGQovw(GI2hz6SK)else P=YUGQovw(WQ6)end;s(P==
o0_XG8FI)
if not IcsJ then local pRCHPl
if Zn3SC and A==1 then pRCHPl=0;while(D4[pRCHPl])do D4[pRCHPl]=
nil;pRCHPl=pRCHPl-1 end end;Zn3SC=nil;pRCHPl=1;for sCffg4HK=Wp9xT-32767,Wp9xT do D4[pRCHPl]=D4[sCffg4HK-x]
pRCHPl=pRCHPl+1 end
for EyljhkFp,uGDn542 in LfEJbh_(crA9EKx)do local DQ=#uGDn542
if DQ>0 and
Wp9xT+1-uGDn542[1]>32768 then
if DQ==1 then
crA9EKx[EyljhkFp]=nil else local s6Ahlni_={}local T6dNu=0
for H=2,DQ do pRCHPl=uGDn542[H]if Wp9xT+1-pRCHPl<=32768 then
T6dNu=T6dNu+1;s6Ahlni_[T6dNu]=pRCHPl end end;crA9EKx[EyljhkFp]=s6Ahlni_ end end end end end end
local function wZdg(YlzZm,vj9879b5,cotcYZ1f)local FRcmT,zfl,itxD=Oh()
iW6CD(cotcYZ1f,FRcmT,zfl,itxD,YlzZm,vj9879b5)local JPHs7A,yzYgnMtr=itxD(y36Aetn)local o=(8-JPHs7A%8)%8
return yzYgnMtr,o end
local function BaX(wmkJ,I1,gXu5hG)local R60Ru4bj,eQWRf,WT2AX=Oh()local _AvO=8;local qEO=7;local q=qEO*16+_AvO;R60Ru4bj(q,8)local WUY7=
I1 and 1 or 0;local _puepou=2;local DYLeJ=_puepou*64+WUY7*32;local udbF=(31- (q*256+
DYLeJ)%31)
DYLeJ=DYLeJ+udbF;R60Ru4bj(DYLeJ,8)
if WUY7 ==1 then local IPPy=I1.adler32;local zYGA2q2=IPPy%256;IPPy=
(IPPy-zYGA2q2)/256;local I9Mw=IPPy%256;IPPy=(IPPy-I9Mw)/256;local e=
IPPy%256;IPPy=(IPPy-e)/256;local BUtIET=IPPy%256
R60Ru4bj(BUtIET,8)R60Ru4bj(e,8)R60Ru4bj(I9Mw,8)R60Ru4bj(zYGA2q2,8)end;iW6CD(gXu5hG,R60Ru4bj,eQWRf,WT2AX,wmkJ,I1)
WT2AX(iPL3B4cr)local dt1=JtAjijkG:Adler32(wmkJ)local V7eMEiVW=dt1%256;dt1=
(dt1-V7eMEiVW)/256;local Co1tUVas=dt1%256
dt1=(dt1-Co1tUVas)/256;local B=dt1%256;dt1=(dt1-B)/256;local UjlBMb=dt1%256
R60Ru4bj(UjlBMb,8)R60Ru4bj(B,8)R60Ru4bj(Co1tUVas,8)R60Ru4bj(V7eMEiVW,8)
local PKWIJ9,rQYWEt=WT2AX(y36Aetn)local nCwsa=(8-PKWIJ9%8)%8;return rQYWEt,nCwsa end
function JtAjijkG:CompressDeflate(NvAj,Icg)local PzMsk,axLuO=ykRppH(NvAj,false,nil,true,Icg)if
not PzMsk then
YAtG_LV3(("Usage: LibDeflate:CompressDeflate(str, configs): "..axLuO),2)end;return wZdg(NvAj,nil,Icg)end
function JtAjijkG:CompressDeflateWithDict(j,As,JmCzKm)local Mwhc,A6z=ykRppH(j,true,As,true,JmCzKm)if not Mwhc then
YAtG_LV3((
"Usage: LibDeflate:CompressDeflateWithDict".."(str, dictionary, configs): "..A6z),2)end
return wZdg(j,As,JmCzKm)end
function JtAjijkG:CompressZlib(_Mk,PXrrrSid)local L9,_KZPScl=ykRppH(_Mk,false,nil,true,PXrrrSid)if
not L9 then
YAtG_LV3(("Usage: LibDeflate:CompressZlib(str, configs): ".._KZPScl),2)end
return BaX(_Mk,nil,PXrrrSid)end
function JtAjijkG:CompressZlibWithDict(dbTwy,R4f819q,Kj1I)
local nTUMgqomA,Id5sIM=ykRppH(dbTwy,true,R4f819q,true,Kj1I)if not nTUMgqomA then
YAtG_LV3(("Usage: LibDeflate:CompressZlibWithDict".."(str, dictionary, configs): "..Id5sIM),2)end;return
BaX(dbTwy,R4f819q,Kj1I)end
local function SJsW11k(gZM2ANLt)local aC72qEnu=gZM2ANLt;local B60J=#gZM2ANLt;local Y4=1;local f=0;local yeCnvcd6=0
local function Iq93c6cA(m54tY2)
local WJWMdKI=RSjapQ[m54tY2]local AhbP
if m54tY2 <=f then AhbP=yeCnvcd6%WJWMdKI
yeCnvcd6=(yeCnvcd6-AhbP)/WJWMdKI;f=f-m54tY2 else local QHFgYUN=RSjapQ[f]
local RoEsr7So,dX,Rz,j177r=JD(aC72qEnu,Y4,Y4+3)
yeCnvcd6=yeCnvcd6+
((RoEsr7So or 0)+ (dX or 0)*256+
(Rz or 0)*65536+ (j177r or 0)*16777216)*QHFgYUN;Y4=Y4+4;f=f+32-m54tY2;AhbP=yeCnvcd6%WJWMdKI;yeCnvcd6=
(yeCnvcd6-AhbP)/WJWMdKI end;return AhbP end
local function nsM0h(j,qCaFw,syvPi)s(f%8 ==0)local NrgSK2=(f/8 <j)and(f/8)or j
for wIH=1,NrgSK2 do local TYWkpc=yeCnvcd6%
256;syvPi=syvPi+1;qCaFw[syvPi]=u(TYWkpc)yeCnvcd6=(yeCnvcd6-
TYWkpc)/256 end;f=f-NrgSK2*8;j=j-NrgSK2;if
(B60J-Y4-j+1)*8+f<0 then return-1 end;for k=Y4,Y4+j-1 do syvPi=syvPi+1
qCaFw[syvPi]=XxJ(aC72qEnu,k,k)end;Y4=Y4+j;return syvPi end
local function Czi(J,gtlO9,Lun)local beUJXhjw=0;local zY7adu=0;local Nlvw=0;local K55
if Lun>0 then
if f<15 and aC72qEnu then local f1MKKJ=RSjapQ[f]
local nFf,EIqL41,iv,rfmMR4=JD(aC72qEnu,Y4,Y4+3)
yeCnvcd6=yeCnvcd6+
((nFf or 0)+ (EIqL41 or 0)*256+
(iv or 0)*65536+ (rfmMR4 or 0)*16777216)*f1MKKJ;Y4=Y4+4;f=f+32 end;local BJcMTdMi=RSjapQ[Lun]f=f-Lun;beUJXhjw=yeCnvcd6%BJcMTdMi;yeCnvcd6=(yeCnvcd6-
beUJXhjw)/BJcMTdMi
beUJXhjw=zC[Lun][beUJXhjw]K55=J[Lun]if beUJXhjw<K55 then return gtlO9[beUJXhjw]end
Nlvw=K55;zY7adu=K55*2;beUJXhjw=beUJXhjw*2 end
for Tq2I=Lun+1,15 do local GNo;GNo=yeCnvcd6%2;yeCnvcd6=(yeCnvcd6-GNo)/2
f=f-1
beUJXhjw=(GNo==1)and(beUJXhjw+1-beUJXhjw%2)or beUJXhjw;K55=J[Tq2I]or 0;local e5x=beUJXhjw-zY7adu;if e5x<K55 then
return gtlO9[Nlvw+e5x]end;Nlvw=Nlvw+K55;zY7adu=zY7adu+K55
zY7adu=zY7adu*2;beUJXhjw=beUJXhjw*2 end;return-10 end;local function IlxN()return(B60J-Y4+1)*8+f end
local function EA_3x01A()
local QrONvWGq=f%8;local D94fnZaa=RSjapQ[QrONvWGq]f=f-QrONvWGq;yeCnvcd6=
(yeCnvcd6-yeCnvcd6%D94fnZaa)/D94fnZaa end;return Iq93c6cA,nsM0h,Czi,IlxN,EA_3x01A end
local function Ki1HJT(XI,FNi)local pRW2nEmK,OR,Arww,BYH,o7E8TLH=SJsW11k(XI)
local N5N27Jd={ReadBits=pRW2nEmK,ReadBytes=OR,Decode=Arww,ReaderBitlenLeft=BYH,SkipToByteBoundary=o7E8TLH,buffer_size=0,buffer={},result_buffer={},dictionary=FNi}return N5N27Jd end
local function wjim8xCV(m,nK,_zr)local f5={}local UAc=_zr
for GYVN=0,nK do local DNlB1V=m[GYVN]or 0;UAc=
(DNlB1V>0 and DNlB1V<UAc)and DNlB1V or UAc;f5[DNlB1V]=(
f5[DNlB1V]or 0)+1 end;if f5[0]==nK+1 then return 0,f5,{},0 end;local Ef=1
for erb6G_E=1,_zr do Ef=Ef*2;Ef=Ef-
(f5[erb6G_E]or 0)if Ef<0 then return Ef end end;local P={}P[1]=0;for QFUU10K=1,_zr-1 do
P[QFUU10K+1]=P[QFUU10K]+ (f5[QFUU10K]or 0)end;local F4AWvI={}for xNPDtul=0,nK do local k8=m[xNPDtul]or 0
if
k8 ~=0 then local HmgRk=P[k8]F4AWvI[HmgRk]=xNPDtul;P[k8]=P[k8]+1 end end
return Ef,f5,F4AWvI,UAc end
local function EQLam(UuCdpVi,fghe,vFXf,CA0uX7n,ze5Vpc3,vwK8,Sk_SiC)
local X0bgPvA,M9CyqH,z0x4qSAN,X0GTupeV,rQ,k=UuCdpVi.buffer,UuCdpVi.buffer_size,UuCdpVi.ReadBits,UuCdpVi.Decode,UuCdpVi.ReaderBitlenLeft,UuCdpVi.result_buffer;local Oc=UuCdpVi.dictionary;local IHovU;local e_wDQjk;local ClglY=1
if Oc and not X0bgPvA[0]then
IHovU=Oc.string_table;e_wDQjk=Oc.strlen;ClglY=-e_wDQjk+1;for S=0,(-e_wDQjk+1)<-257 and
-257 or(-e_wDQjk+1),-1 do
X0bgPvA[S]=QJf[IHovU[e_wDQjk+S]]end end
repeat local NKetZhs=X0GTupeV(fghe,vFXf,CA0uX7n)
if
NKetZhs<0 or NKetZhs>285 then return-10 elseif NKetZhs<256 then M9CyqH=M9CyqH+1;X0bgPvA[M9CyqH]=QJf[NKetZhs]elseif
NKetZhs>256 then NKetZhs=NKetZhs-256;local EFLZ0N1=el[NKetZhs]EFLZ0N1=
(NKetZhs>=8)and(
EFLZ0N1+z0x4qSAN(Wu_uIt[NKetZhs]))or EFLZ0N1
NKetZhs=X0GTupeV(ze5Vpc3,vwK8,Sk_SiC)if NKetZhs<0 or NKetZhs>29 then return-10 end
local gL=w[NKetZhs]gL=
(gL>4)and(gL+z0x4qSAN(sgeP[NKetZhs]))or gL;local m4=M9CyqH-gL+1;if
m4 <ClglY then return-11 end
if m4 >=-257 then for rNOL8G=1,EFLZ0N1 do M9CyqH=M9CyqH+1
X0bgPvA[M9CyqH]=X0bgPvA[m4]m4=m4+1 end else m4=e_wDQjk+m4
for q=1,EFLZ0N1 do
M9CyqH=M9CyqH+1;X0bgPvA[M9CyqH]=QJf[IHovU[m4]]m4=m4+1 end end end;if rQ()<0 then return 2 end
if M9CyqH>=65536 then
k[#k+1]=o5sms(X0bgPvA,"",1,32768)
for lKO=32769,M9CyqH do X0bgPvA[lKO-32768]=X0bgPvA[lKO]end;M9CyqH=M9CyqH-32768;X0bgPvA[M9CyqH+1]=nil end until NKetZhs==256;UuCdpVi.buffer_size=M9CyqH;return 0 end
local function qTDt(hcwgu)
local omgCdqp8,X17eHTx,SGF,myIHU,xxNCdF,_cl1b,Xz18nk=hcwgu.buffer,hcwgu.buffer_size,hcwgu.ReadBits,hcwgu.ReadBytes,hcwgu.ReaderBitlenLeft,hcwgu.SkipToByteBoundary,hcwgu.result_buffer;_cl1b()local P=SGF(16)if xxNCdF()<0 then return 2 end;local sTX4=SGF(16)if
xxNCdF()<0 then return 2 end
if P%256+sTX4%256 ~=255 then return-2 end;if
(P-P%256)/256+ (sTX4-sTX4%256)/256 ~=255 then return-2 end
X17eHTx=myIHU(P,omgCdqp8,X17eHTx)if X17eHTx<0 then return 2 end
if X17eHTx>=65536 then
Xz18nk[#Xz18nk+1]=o5sms(omgCdqp8,"",1,32768)
for A0TJx=32769,X17eHTx do omgCdqp8[A0TJx-32768]=omgCdqp8[A0TJx]end;X17eHTx=X17eHTx-32768;omgCdqp8[X17eHTx+1]=nil end;hcwgu.buffer_size=X17eHTx;return 0 end
local function v(Nqdkw)return EQLam(Nqdkw,hw18,_,7,rDtVf,xSebv5Jc,5)end
local function Ta(t)local QbMO,wYZ=t.ReadBits,t.Decode;local aMd=QbMO(5)+257;local o0pf=QbMO(5)+1;local tx1LD=
QbMO(4)+4;if aMd>286 or o0pf>30 then return-3 end;local N3ROeR={}for LOBqxO=1,tx1LD do
N3ROeR[CM[LOBqxO]]=QbMO(3)end;local I1oQVnUd,oTX,WZlF4,IxqPDOWH=wjim8xCV(N3ROeR,18,7)if
I1oQVnUd~=0 then return-4 end;local GZqV={}local OVubrDw_={}local G2_TeR8=0
while G2_TeR8 <aMd+o0pf do
local m8;local mcoAHO;m8=wYZ(oTX,WZlF4,IxqPDOWH)
if m8 <0 then return m8 elseif m8 <16 then if G2_TeR8 <aMd then
GZqV[G2_TeR8]=m8 else OVubrDw_[G2_TeR8-aMd]=m8 end;G2_TeR8=
G2_TeR8+1 else mcoAHO=0
if m8 ==16 then if G2_TeR8 ==0 then return-5 end;if
G2_TeR8-1 <aMd then mcoAHO=GZqV[G2_TeR8-1]else
mcoAHO=OVubrDw_[G2_TeR8-aMd-1]end;m8=3+QbMO(2)elseif m8 ==17 then
m8=3+QbMO(3)else m8=11+QbMO(7)end;if G2_TeR8+m8 >aMd+o0pf then return-6 end
while m8 >0 do m8=m8-1
if
G2_TeR8 <aMd then GZqV[G2_TeR8]=mcoAHO else OVubrDw_[G2_TeR8-aMd]=mcoAHO end;G2_TeR8=G2_TeR8+1 end end end;if(GZqV[256]or 0)==0 then return-9 end
local yk,OPSPMfr_,QnNOl,aQs=wjim8xCV(GZqV,aMd-1,15)if
(yk~=0 and(yk<0 or aMd~=
(OPSPMfr_[0]or 0)+ (OPSPMfr_[1]or 0)))then return-7 end
local uow_0tb,tykg,C_pPyW,mgb4b=wjim8xCV(OVubrDw_,o0pf-1,15)if
(uow_0tb~=0 and(uow_0tb<0 or
o0pf~= (tykg[0]or 0)+ (tykg[1]or 0)))then return-8 end;return
EQLam(t,OPSPMfr_,QnNOl,aQs,tykg,C_pPyW,mgb4b)end
local function unArcvQl(d3gFWO)local D=d3gFWO.ReadBits;local obodPKnu
while not obodPKnu do obodPKnu=(D(1)==1)local oVSp=D(2)
local uBJ;if oVSp==0 then uBJ=qTDt(d3gFWO)elseif oVSp==1 then uBJ=v(d3gFWO)elseif oVSp==2 then uBJ=Ta(d3gFWO)else
return nil,-1 end;if uBJ~=0 then
return nil,uBJ end end
d3gFWO.result_buffer[#d3gFWO.result_buffer+1]=o5sms(d3gFWO.buffer,"",1,d3gFWO.buffer_size)local kgdzk=o5sms(d3gFWO.result_buffer)return kgdzk end
local function h6Ub7U(A,MP)local jb=Ki1HJT(A,MP)local uKSj,YXgXQB=unArcvQl(jb)
if not uKSj then return nil,YXgXQB end;local bvL1X4=jb.ReaderBitlenLeft()
local PPNahh=(bvL1X4-bvL1X4%8)/8;return uKSj,PPNahh end
local function Gm(z2g,m9JTkVv6)local Q=Ki1HJT(z2g,m9JTkVv6)local bWkP=Q.ReadBits;local JtFj=bWkP(8)if
Q.ReaderBitlenLeft()<0 then return nil,2 end;local PQ3=JtFj%16
local _xCtN=(JtFj-PQ3)/16;if PQ3 ~=8 then return nil,-12 end;if _xCtN>7 then return nil,-13 end
local JVpe=bWkP(8)if Q.ReaderBitlenLeft()<0 then return nil,2 end;if
(JtFj*256+JVpe)%31 ~=0 then return nil,-14 end;local nG36XmZC=(
(JVpe-JVpe%32)/32%2)local Vf26=(
(JVpe-JVpe%64)/64%4)
if nG36XmZC==1 then
if not m9JTkVv6 then return nil,-16 end;local I7=bWkP(8)local Upw=bWkP(8)local nqBfKL=bWkP(8)local gs3a=bWkP(8)
local AkKaBC=I7*16777216+
Upw*65536+nqBfKL*256+gs3a;if Q.ReaderBitlenLeft()<0 then return nil,2 end;if not
vj(AkKaBC,m9JTkVv6.adler32)then return nil,-17 end end;local xUGt,_U=unArcvQl(Q)if not xUGt then return nil,_U end
Q.SkipToByteBoundary()local hkI39=bWkP(8)local MwwN=bWkP(8)local oZ9=bWkP(8)local OXlT0=bWkP(8)if
Q.ReaderBitlenLeft()<0 then return nil,2 end;local V=
hkI39*16777216+MwwN*65536+oZ9*256+OXlT0
local zIYNIXy1=JtAjijkG:Adler32(xUGt)if not vj(V,zIYNIXy1)then return nil,-15 end
local c=Q.ReaderBitlenLeft()local mReHt4h=(c-c%8)/8;return xUGt,mReHt4h end
function JtAjijkG:DecompressDeflate(OmRH8)local GY,oukM79R=ykRppH(OmRH8)if not GY then
YAtG_LV3(("Usage: LibDeflate:DecompressDeflate(str): "..
oukM79R),2)end;return h6Ub7U(OmRH8)end
function JtAjijkG:DecompressDeflateWithDict(D_j,mZPe4w)local OvZ,cBOpf=ykRppH(D_j,true,mZPe4w)if not OvZ then
YAtG_LV3((
"Usage: LibDeflate:DecompressDeflateWithDict(str, dictionary): "..cBOpf),2)end
return h6Ub7U(D_j,mZPe4w)end
function JtAjijkG:DecompressZlib(KZYA5y)local YoCAN7OU,FoP=ykRppH(KZYA5y)if not YoCAN7OU then
YAtG_LV3((
"Usage: LibDeflate:DecompressZlib(str): "..FoP),2)end;return Gm(KZYA5y)end
function JtAjijkG:DecompressZlibWithDict(jqtWXY,XgRb)local G3e,GoP6=ykRppH(jqtWXY,true,XgRb)if not G3e then
YAtG_LV3((
"Usage: LibDeflate:DecompressZlibWithDict(str, dictionary): "..GoP6),2)end;return Gm(jqtWXY,XgRb)end
do RkGFh6={}for NYc8=0,143 do RkGFh6[NYc8]=8 end
for Dff8=144,255 do RkGFh6[Dff8]=9 end;for lEYwsOG9=256,279 do RkGFh6[lEYwsOG9]=7 end
for M=280,287 do RkGFh6[M]=8 end;mMp={}for Vt95q2G=0,31 do mMp[Vt95q2G]=5 end;local cZ_
cZ_,hw18,_=wjim8xCV(RkGFh6,287,9)s(cZ_==0)cZ_,rDtVf,xSebv5Jc=wjim8xCV(mMp,31,5)s(cZ_==0)
Qlmlet=O(hw18,RkGFh6,287,9)nvCiFt7r=O(rDtVf,mMp,31,5)end;return JtAjijkG
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