mirror of
https://github.com/0x5eal/luau-unzip.git
synced 2025-04-20 05:23:46 +01:00
refactor: minor sylistic changes
Swaps places with the pattern: ```luau x = x + 1 ``` to use: ```luau x += 1 ```
This commit is contained in:
parent
c2e638cbec
commit
10a399c91f
GPG key ID:
429EF1C337871656
2 changed files with 255 additions and 256 deletions
453
lib/inflate.luau
453
lib/inflate.luau
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@ -2,49 +2,49 @@ local Tree = {}
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export type Tree = typeof(setmetatable({} :: TreeInner, { __index = Tree }))
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export type Tree = typeof(setmetatable({} :: TreeInner, { __index = Tree }))
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type TreeInner = {
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type TreeInner = {
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table: { number }, -- len: 16 (🏳️⚧️❓)
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table: { number }, -- len: 16
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trans: { number }, -- len: 288
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trans: { number }, -- len: 288
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}
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}
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function Tree.new(): Tree
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function Tree.new(): Tree
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return setmetatable(
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return setmetatable(
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{
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{
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table = table.create(16, 0),
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table = table.create(16, 0),
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trans = table.create(288, 0),
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trans = table.create(288, 0),
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} :: TreeInner,
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} :: TreeInner,
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{ __index = Tree }
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{ __index = Tree }
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)
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)
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end
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end
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local Data = {}
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local Data = {}
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export type Data = typeof(setmetatable({} :: DataInner, { __index = Data }))
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export type Data = typeof(setmetatable({} :: DataInner, { __index = Data }))
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export type DataInner = {
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export type DataInner = {
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source: buffer,
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source: buffer,
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sourceIndex: number,
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sourceIndex: number,
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tag: number,
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tag: number,
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bitcount: number,
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bitcount: number,
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dest: buffer,
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dest: buffer,
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destLen: number,
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destLen: number,
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ltree: Tree,
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ltree: Tree,
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dtree: Tree,
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dtree: Tree,
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}
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}
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function Data.new(source: buffer, dest: buffer): Data
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function Data.new(source: buffer, dest: buffer): Data
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return setmetatable(
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return setmetatable(
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{
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{
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source = source,
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source = source,
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sourceIndex = 0,
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sourceIndex = 0,
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tag = 0,
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tag = 0,
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bitcount = 0,
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bitcount = 0,
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dest = dest,
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dest = dest,
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destLen = 0,
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destLen = 0,
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ltree = Tree.new(),
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ltree = Tree.new(),
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dtree = Tree.new(),
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dtree = Tree.new(),
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} :: DataInner,
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} :: DataInner,
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{ __index = Data }
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{ __index = Data }
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)
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)
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end
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end
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-- Static structures
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-- Static structures
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@ -58,7 +58,6 @@ local distBits = table.create(30, 0)
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local distBase = table.create(30, 0)
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local distBase = table.create(30, 0)
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-- Special ordering of code length codes
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-- Special ordering of code length codes
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-- stylua: ignore
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local clcIndex = {
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local clcIndex = {
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16, 17, 18, 0, 8, 7, 9, 6,
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16, 17, 18, 0, 8, 7, 9, 6,
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10, 5, 11, 4, 12, 3, 13, 2,
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10, 5, 11, 4, 12, 3, 13, 2,
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@ -69,270 +68,270 @@ local codeTree = Tree.new()
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local lengths = table.create(288 + 32, 0)
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local lengths = table.create(288 + 32, 0)
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local function buildBitsBase(bits: { number }, base: { number }, delta: number, first: number)
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local function buildBitsBase(bits: { number }, base: { number }, delta: number, first: number)
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local sum = first
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local sum = first
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-- build bits table
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-- build bits table
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for i = 0, delta - 1 do
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for i = 0, delta - 1 do
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bits[i] = 0
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bits[i] = 0
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end
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end
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for i = 0, 29 - delta do
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for i = 0, 29 - delta do
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bits[i + delta] = math.floor(i / delta)
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bits[i + delta] = math.floor(i / delta)
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end
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end
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-- build base table
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-- build base table
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for i = 0, 29 do
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for i = 0, 29 do
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base[i] = sum
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base[i] = sum
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sum = sum + bit32.lshift(1, bits[i])
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sum += bit32.lshift(1, bits[i])
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end
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end
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end
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end
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local function buildFixedTrees(lengthTree: Tree, distTree: Tree)
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local function buildFixedTrees(lengthTree: Tree, distTree: Tree)
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-- build fixed length tree
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-- build fixed length tree
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for i = 0, 6 do
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for i = 0, 6 do
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lengthTree.table[i] = 0
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lengthTree.table[i] = 0
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end
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end
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lengthTree.table[7] = 24
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lengthTree.table[7] = 24
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lengthTree.table[8] = 152
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lengthTree.table[8] = 152
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lengthTree.table[9] = 112
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lengthTree.table[9] = 112
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for i = 0, 23 do
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for i = 0, 23 do
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lengthTree.trans[i] = 256 + i
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lengthTree.trans[i] = 256 + i
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end
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end
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for i = 0, 143 do
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for i = 0, 143 do
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lengthTree.trans[24 + i] = i
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lengthTree.trans[24 + i] = i
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end
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end
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for i = 0, 7 do
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for i = 0, 7 do
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lengthTree.trans[24 + 144 + i] = 280 + i
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lengthTree.trans[24 + 144 + i] = 280 + i
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end
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end
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for i = 0, 111 do
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for i = 0, 111 do
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lengthTree.trans[24 + 144 + 8 + i] = 144 + i
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lengthTree.trans[24 + 144 + 8 + i] = 144 + i
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end
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end
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-- build fixed distance tree
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-- build fixed distance tree
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for i = 0, 4 do
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for i = 0, 4 do
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distTree.table[i] = 0
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distTree.table[i] = 0
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end
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end
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distTree.table[5] = 32
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distTree.table[5] = 32
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for i = 0, 31 do
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for i = 0, 31 do
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distTree.trans[i] = i
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distTree.trans[i] = i
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end
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end
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end
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end
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local offs = table.create(16, 0)
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local offs = table.create(16, 0)
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local function buildTree(t: Tree, lengths: { number }, off: number, num: number)
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local function buildTree(t: Tree, lengths: { number }, off: number, num: number)
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-- clear code length count table
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-- clear code length count table
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for i = 0, 15 do
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for i = 0, 15 do
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t.table[i] = 0
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t.table[i] = 0
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end
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end
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-- scan symbol lengths, and sum code length counts
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-- scan symbol lengths, and sum code length counts
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for i = 0, num - 1 do
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for i = 0, num - 1 do
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t.table[lengths[off + i]] += 1
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t.table[lengths[off + i]] += 1
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end
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end
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t.table[0] = 0
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t.table[0] = 0
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-- compute offset table for distribution sort
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-- compute offset table for distribution sort
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local sum = 0
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local sum = 0
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for i = 0, 15 do
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for i = 0, 15 do
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offs[i] = sum
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offs[i] = sum
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sum = sum + t.table[i]
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sum += t.table[i]
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end
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end
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-- create code->symbol translation table
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-- create code->symbol translation table
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for i = 0, num - 1 do
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for i = 0, num - 1 do
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local len = lengths[off + i]
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local len = lengths[off + i]
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if len > 0 then
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if len > 0 then
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t.trans[offs[len]] = i
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t.trans[offs[len]] = i
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offs[len] += 1
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offs[len] += 1
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end
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end
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end
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end
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end
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end
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local function getBit(d: Data): number
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local function getBit(d: Data): number
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if d.bitcount <= 0 then
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if d.bitcount <= 0 then
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d.tag = buffer.readu8(d.source, d.sourceIndex)
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d.tag = buffer.readu8(d.source, d.sourceIndex)
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d.sourceIndex += 1
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d.sourceIndex += 1
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d.bitcount = 8
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d.bitcount = 8
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end
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end
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local bit = bit32.band(d.tag, 1)
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local bit = bit32.band(d.tag, 1)
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d.tag = bit32.rshift(d.tag, 1)
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d.tag = bit32.rshift(d.tag, 1)
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d.bitcount -= 1
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d.bitcount -= 1
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return bit
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return bit
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end
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end
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local function readBits(d: Data, num: number?, base: number): number
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local function readBits(d: Data, num: number?, base: number): number
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if not num then
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if not num then
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return base
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return base
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end
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end
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while d.bitcount < 24 and d.sourceIndex < buffer.len(d.source) do
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while d.bitcount < 24 and d.sourceIndex < buffer.len(d.source) do
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d.tag = bit32.bor(d.tag, bit32.lshift(buffer.readu8(d.source, d.sourceIndex), d.bitcount))
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d.tag = bit32.bor(d.tag, bit32.lshift(buffer.readu8(d.source, d.sourceIndex), d.bitcount))
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d.sourceIndex += 1
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d.sourceIndex += 1
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d.bitcount += 8
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d.bitcount += 8
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end
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end
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local val = bit32.band(d.tag, bit32.rshift(0xffff, 16 - num))
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local val = bit32.band(d.tag, bit32.rshift(0xffff, 16 - num))
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d.tag = bit32.rshift(d.tag, num)
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d.tag = bit32.rshift(d.tag, num)
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d.bitcount -= num
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d.bitcount -= num
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return val + base
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return val + base
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end
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end
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local function decodeSymbol(d: Data, t: Tree): number
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local function decodeSymbol(d: Data, t: Tree): number
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while d.bitcount < 24 and d.sourceIndex < buffer.len(d.source) do
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while d.bitcount < 24 and d.sourceIndex < buffer.len(d.source) do
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d.tag = bit32.bor(d.tag, bit32.lshift(buffer.readu8(d.source, d.sourceIndex), d.bitcount))
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d.tag = bit32.bor(d.tag, bit32.lshift(buffer.readu8(d.source, d.sourceIndex), d.bitcount))
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d.sourceIndex += 1
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d.sourceIndex += 1
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d.bitcount += 8
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d.bitcount += 8
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end
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end
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local sum, cur, len = 0, 0, 0
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local sum, cur, len = 0, 0, 0
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local tag = d.tag
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local tag = d.tag
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repeat
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repeat
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cur = 2 * cur + bit32.band(tag, 1)
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cur = 2 * cur + bit32.band(tag, 1)
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tag = bit32.rshift(tag, 1)
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tag = bit32.rshift(tag, 1)
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len += 1
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len += 1
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sum += t.table[len]
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sum += t.table[len]
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cur -= t.table[len]
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cur -= t.table[len]
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until cur < 0
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until cur < 0
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d.tag = tag
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d.tag = tag
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d.bitcount -= len
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d.bitcount -= len
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return t.trans[sum + cur]
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return t.trans[sum + cur]
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end
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end
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local function decodeTrees(d: Data, lengthTree: Tree, distTree: Tree)
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local function decodeTrees(d: Data, lengthTree: Tree, distTree: Tree)
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local hlit = readBits(d, 5, 257)
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local hlit = readBits(d, 5, 257)
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local hdist = readBits(d, 5, 1)
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local hdist = readBits(d, 5, 1)
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local hclen = readBits(d, 4, 4)
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local hclen = readBits(d, 4, 4)
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for i = 0, 18 do
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for i = 0, 18 do
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lengths[i] = 0
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lengths[i] = 0
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end
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end
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for i = 0, hclen - 1 do
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for i = 0, hclen - 1 do
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lengths[clcIndex[i + 1]] = readBits(d, 3, 0)
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lengths[clcIndex[i + 1]] = readBits(d, 3, 0)
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end
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end
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buildTree(codeTree, lengths, 0, 19)
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buildTree(codeTree, lengths, 0, 19)
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local num = 0
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local num = 0
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while num < hlit + hdist do
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while num < hlit + hdist do
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local sym = decodeSymbol(d, codeTree)
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local sym = decodeSymbol(d, codeTree)
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if sym == 16 then
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if sym == 16 then
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local prev = lengths[num - 1]
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local prev = lengths[num - 1]
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for _ = 1, readBits(d, 2, 3) do
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for _ = 1, readBits(d, 2, 3) do
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lengths[num] = prev
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lengths[num] = prev
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num += 1
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num += 1
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end
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end
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elseif sym == 17 then
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elseif sym == 17 then
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for _ = 1, readBits(d, 3, 3) do
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for _ = 1, readBits(d, 3, 3) do
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lengths[num] = 0
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lengths[num] = 0
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num += 1
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num += 1
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end
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end
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elseif sym == 18 then
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elseif sym == 18 then
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for _ = 1, readBits(d, 7, 11) do
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for _ = 1, readBits(d, 7, 11) do
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lengths[num] = 0
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lengths[num] = 0
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num += 1
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num += 1
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end
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end
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else
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else
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lengths[num] = sym
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lengths[num] = sym
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num += 1
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num += 1
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end
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end
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end
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end
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buildTree(lengthTree, lengths, 0, hlit)
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buildTree(lengthTree, lengths, 0, hlit)
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buildTree(distTree, lengths, hlit, hdist)
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buildTree(distTree, lengths, hlit, hdist)
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end
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end
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local function inflateBlockData(d: Data, lengthTree: Tree, distTree: Tree)
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local function inflateBlockData(d: Data, lengthTree: Tree, distTree: Tree)
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while true do
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while true do
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local sym = decodeSymbol(d, lengthTree)
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local sym = decodeSymbol(d, lengthTree)
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if sym == 256 then
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if sym == 256 then
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return
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return
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end
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end
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if sym < 256 then
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if sym < 256 then
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buffer.writeu8(d.dest, d.destLen, sym)
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buffer.writeu8(d.dest, d.destLen, sym)
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d.destLen += 1
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d.destLen += 1
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else
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else
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sym -= 257
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sym -= 257
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local length = readBits(d, lengthBits[sym], lengthBase[sym])
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local length = readBits(d, lengthBits[sym], lengthBase[sym])
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local dist = decodeSymbol(d, distTree)
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local dist = decodeSymbol(d, distTree)
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local offs = d.destLen - readBits(d, distBits[dist], distBase[dist])
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local offs = d.destLen - readBits(d, distBits[dist], distBase[dist])
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for i = offs, offs + length - 1 do
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for i = offs, offs + length - 1 do
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buffer.writeu8(d.dest, d.destLen, buffer.readu8(d.dest, i))
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buffer.writeu8(d.dest, d.destLen, buffer.readu8(d.dest, i))
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d.destLen += 1
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d.destLen += 1
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end
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end
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end
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end
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end
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end
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end
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end
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local function inflateUncompressedBlock(d: Data)
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local function inflateUncompressedBlock(d: Data)
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while d.bitcount > 8 do
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while d.bitcount > 8 do
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d.sourceIndex -= 1
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d.sourceIndex -= 1
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d.bitcount -= 8
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d.bitcount -= 8
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end
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end
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local length = buffer.readu8(d.source, d.sourceIndex + 1)
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local length = buffer.readu8(d.source, d.sourceIndex + 1)
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length = 256 * length + buffer.readu8(d.source, d.sourceIndex)
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length = 256 * length + buffer.readu8(d.source, d.sourceIndex)
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local invlength = buffer.readu8(d.source, d.sourceIndex + 3)
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local invlength = buffer.readu8(d.source, d.sourceIndex + 3)
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invlength = 256 * invlength + buffer.readu8(d.source, d.sourceIndex + 2)
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invlength = 256 * invlength + buffer.readu8(d.source, d.sourceIndex + 2)
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if length ~= bit32.bxor(invlength, 0xffff) then
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if length ~= bit32.bxor(invlength, 0xffff) then
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error("Invalid block length")
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error("Invalid block length")
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end
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end
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d.sourceIndex += 4
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d.sourceIndex += 4
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for _ = 1, length do
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for _ = 1, length do
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buffer.writeu8(d.dest, d.destLen, buffer.readu8(d.source, d.sourceIndex))
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buffer.writeu8(d.dest, d.destLen, buffer.readu8(d.source, d.sourceIndex))
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d.destLen += 1
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d.destLen += 1
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||||||
d.sourceIndex += 1
|
d.sourceIndex += 1
|
||||||
end
|
end
|
||||||
|
|
||||||
d.bitcount = 0
|
d.bitcount = 0
|
||||||
end
|
end
|
||||||
|
|
||||||
local function uncompress(source: buffer): buffer
|
local function uncompress(source: buffer): buffer
|
||||||
local dest = buffer.create(buffer.len(source) * 4)
|
local dest = buffer.create(buffer.len(source) * 4)
|
||||||
local d = Data.new(source, dest)
|
local d = Data.new(source, dest)
|
||||||
|
|
||||||
repeat
|
repeat
|
||||||
local bfinal = getBit(d)
|
local bfinal = getBit(d)
|
||||||
local btype = readBits(d, 2, 0)
|
local btype = readBits(d, 2, 0)
|
||||||
|
|
||||||
if btype == 0 then
|
if btype == 0 then
|
||||||
inflateUncompressedBlock(d)
|
inflateUncompressedBlock(d)
|
||||||
elseif btype == 1 then
|
elseif btype == 1 then
|
||||||
inflateBlockData(d, staticLengthTree, staticDistTree)
|
inflateBlockData(d, staticLengthTree, staticDistTree)
|
||||||
elseif btype == 2 then
|
elseif btype == 2 then
|
||||||
decodeTrees(d, d.ltree, d.dtree)
|
decodeTrees(d, d.ltree, d.dtree)
|
||||||
inflateBlockData(d, d.ltree, d.dtree)
|
inflateBlockData(d, d.ltree, d.dtree)
|
||||||
else
|
else
|
||||||
error("Invalid block type")
|
error("Invalid block type")
|
||||||
end
|
end
|
||||||
until bfinal == 1
|
until bfinal == 1
|
||||||
|
|
||||||
if d.destLen < buffer.len(dest) then
|
if d.destLen < buffer.len(dest) then
|
||||||
local result = buffer.create(d.destLen)
|
local result = buffer.create(d.destLen)
|
||||||
buffer.copy(result, 0, dest, 0, d.destLen)
|
buffer.copy(result, 0, dest, 0, d.destLen)
|
||||||
return result
|
return result
|
||||||
end
|
end
|
||||||
|
|
||||||
return dest
|
return dest
|
||||||
end
|
end
|
||||||
|
|
||||||
-- Initialize static trees and tables
|
-- Initialize static trees and tables
|
||||||
|
|
|
||||||
|
|
@ -127,7 +127,7 @@ function ZipReader.parseCentralDirectory(self: ZipReader): ()
|
||||||
if buffer.readu32(self.data, pos) == SIGNATURES.END_OF_CENTRAL_DIR then
|
if buffer.readu32(self.data, pos) == SIGNATURES.END_OF_CENTRAL_DIR then
|
||||||
break
|
break
|
||||||
end
|
end
|
||||||
pos = pos - 1
|
pos -= 1
|
||||||
end
|
end
|
||||||
|
|
||||||
-- Central Directory offset is stored 16 bytes into the EoCD record
|
-- Central Directory offset is stored 16 bytes into the EoCD record
|
||||||
|
|
@ -373,12 +373,12 @@ function ZipReader.getStats(self: ZipReader): ZipStatistics
|
||||||
-- Iterate through the entries, updating stats
|
-- Iterate through the entries, updating stats
|
||||||
for _, entry in self.entries do
|
for _, entry in self.entries do
|
||||||
if entry.isDirectory then
|
if entry.isDirectory then
|
||||||
stats.dirCount = stats.dirCount + 1
|
stats.dirCount += 1
|
||||||
continue
|
continue
|
||||||
end
|
end
|
||||||
|
|
||||||
stats.fileCount = stats.fileCount + 1
|
stats.fileCount += 1
|
||||||
stats.totalSize = stats.totalSize + entry.size
|
stats.totalSize += entry.size
|
||||||
end
|
end
|
||||||
|
|
||||||
return stats
|
return stats
|
||||||
|
|
|
||||||
Loading…
Add table
Reference in a new issue