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-rw-r--r--lua/mason-vendor/zzlib/inflate-bit32.lua285
1 files changed, 285 insertions, 0 deletions
diff --git a/lua/mason-vendor/zzlib/inflate-bit32.lua b/lua/mason-vendor/zzlib/inflate-bit32.lua
new file mode 100644
index 00000000..fc426018
--- /dev/null
+++ b/lua/mason-vendor/zzlib/inflate-bit32.lua
@@ -0,0 +1,285 @@
+-- stylua: ignore start
+
+-- zzlib-bit32 - zlib decompression in Lua - version using bit/bit32 libraries
+
+-- Copyright (c) 2016-2023 Francois Galea <fgalea at free.fr>
+-- This program is free software. It comes without any warranty, to
+-- the extent permitted by applicable law. You can redistribute it
+-- and/or modify it under the terms of the Do What The Fuck You Want
+-- To Public License, Version 2, as published by Sam Hocevar. See
+-- the COPYING file or http://www.wtfpl.net/ for more details.
+
+
+local inflate = {}
+
+local bit = bit32 or bit
+
+inflate.band = bit.band
+inflate.rshift = bit.rshift
+
+function inflate.bitstream_init(file)
+ local bs = {
+ file = file, -- the open file handle
+ buf = nil, -- character buffer
+ len = nil, -- length of character buffer
+ pos = 1, -- position in char buffer, next to be read
+ b = 0, -- bit buffer
+ n = 0, -- number of bits in buffer
+ }
+ -- get rid of n first bits
+ function bs:flushb(n)
+ self.n = self.n - n
+ self.b = bit.rshift(self.b,n)
+ end
+ -- returns the next byte from the stream, excluding any half-read bytes
+ function bs:next_byte()
+ if self.pos > self.len then
+ self.buf = self.file:read(4096)
+ self.len = self.buf:len()
+ self.pos = 1
+ end
+ local pos = self.pos
+ self.pos = pos + 1
+ return self.buf:byte(pos)
+ end
+ -- peek a number of n bits from stream
+ function bs:peekb(n)
+ while self.n < n do
+ self.b = self.b + bit.lshift(self:next_byte(),self.n)
+ self.n = self.n + 8
+ end
+ return bit.band(self.b,bit.lshift(1,n)-1)
+ end
+ -- get a number of n bits from stream
+ function bs:getb(n)
+ local ret = bs:peekb(n)
+ self.n = self.n - n
+ self.b = bit.rshift(self.b,n)
+ return ret
+ end
+ -- get next variable-size of maximum size=n element from stream, according to Huffman table
+ function bs:getv(hufftable,n)
+ local e = hufftable[bs:peekb(n)]
+ local len = bit.band(e,15)
+ local ret = bit.rshift(e,4)
+ self.n = self.n - len
+ self.b = bit.rshift(self.b,len)
+ return ret
+ end
+ function bs:close()
+ if self.file then
+ self.file:close()
+ end
+ end
+ if type(file) == "string" then
+ bs.file = nil
+ bs.buf = file
+ else
+ bs.buf = file:read(4096)
+ end
+ bs.len = bs.buf:len()
+ return bs
+end
+
+local function hufftable_create(depths)
+ local nvalues = #depths
+ local nbits = 1
+ local bl_count = {}
+ local next_code = {}
+ for i=1,nvalues do
+ local d = depths[i]
+ if d > nbits then
+ nbits = d
+ end
+ bl_count[d] = (bl_count[d] or 0) + 1
+ end
+ local table = {}
+ local code = 0
+ bl_count[0] = 0
+ for i=1,nbits do
+ code = (code + (bl_count[i-1] or 0)) * 2
+ next_code[i] = code
+ end
+ for i=1,nvalues do
+ local len = depths[i] or 0
+ if len > 0 then
+ local e = (i-1)*16 + len
+ local code = next_code[len]
+ local rcode = 0
+ for j=1,len do
+ rcode = rcode + bit.lshift(bit.band(1,bit.rshift(code,j-1)),len-j)
+ end
+ for j=0,2^nbits-1,2^len do
+ table[j+rcode] = e
+ end
+ next_code[len] = next_code[len] + 1
+ end
+ end
+ return table,nbits
+end
+
+local function block_loop(out,bs,nlit,ndist,littable,disttable)
+ local lit
+ repeat
+ lit = bs:getv(littable,nlit)
+ if lit < 256 then
+ table.insert(out,lit)
+ elseif lit > 256 then
+ local nbits = 0
+ local size = 3
+ local dist = 1
+ if lit < 265 then
+ size = size + lit - 257
+ elseif lit < 285 then
+ nbits = bit.rshift(lit-261,2)
+ size = size + bit.lshift(bit.band(lit-261,3)+4,nbits)
+ else
+ size = 258
+ end
+ if nbits > 0 then
+ size = size + bs:getb(nbits)
+ end
+ local v = bs:getv(disttable,ndist)
+ if v < 4 then
+ dist = dist + v
+ else
+ nbits = bit.rshift(v-2,1)
+ dist = dist + bit.lshift(bit.band(v,1)+2,nbits)
+ dist = dist + bs:getb(nbits)
+ end
+ local p = #out-dist+1
+ while size > 0 do
+ table.insert(out,out[p])
+ p = p + 1
+ size = size - 1
+ end
+ end
+ until lit == 256
+end
+
+local function block_dynamic(out,bs)
+ local order = { 17, 18, 19, 1, 9, 8, 10, 7, 11, 6, 12, 5, 13, 4, 14, 3, 15, 2, 16 }
+ local hlit = 257 + bs:getb(5)
+ local hdist = 1 + bs:getb(5)
+ local hclen = 4 + bs:getb(4)
+ local depths = {}
+ for i=1,hclen do
+ local v = bs:getb(3)
+ depths[order[i]] = v
+ end
+ for i=hclen+1,19 do
+ depths[order[i]] = 0
+ end
+ local lengthtable,nlen = hufftable_create(depths)
+ local i=1
+ while i<=hlit+hdist do
+ local v = bs:getv(lengthtable,nlen)
+ if v < 16 then
+ depths[i] = v
+ i = i + 1
+ elseif v < 19 then
+ local nbt = {2,3,7}
+ local nb = nbt[v-15]
+ local c = 0
+ local n = 3 + bs:getb(nb)
+ if v == 16 then
+ c = depths[i-1]
+ elseif v == 18 then
+ n = n + 8
+ end
+ for j=1,n do
+ depths[i] = c
+ i = i + 1
+ end
+ else
+ error("wrong entry in depth table for literal/length alphabet: "..v);
+ end
+ end
+ local litdepths = {} for i=1,hlit do table.insert(litdepths,depths[i]) end
+ local littable,nlit = hufftable_create(litdepths)
+ local distdepths = {} for i=hlit+1,#depths do table.insert(distdepths,depths[i]) end
+ local disttable,ndist = hufftable_create(distdepths)
+ block_loop(out,bs,nlit,ndist,littable,disttable)
+end
+
+local function block_static(out,bs)
+ local cnt = { 144, 112, 24, 8 }
+ local dpt = { 8, 9, 7, 8 }
+ local depths = {}
+ for i=1,4 do
+ local d = dpt[i]
+ for j=1,cnt[i] do
+ table.insert(depths,d)
+ end
+ end
+ local littable,nlit = hufftable_create(depths)
+ depths = {}
+ for i=1,32 do
+ depths[i] = 5
+ end
+ local disttable,ndist = hufftable_create(depths)
+ block_loop(out,bs,nlit,ndist,littable,disttable)
+end
+
+local function block_uncompressed(out,bs)
+ bs:flushb(bit.band(bs.n,7))
+ local len = bs:getb(16)
+ if bs.n > 0 then
+ error("Unexpected.. should be zero remaining bits in buffer.")
+ end
+ local nlen = bs:getb(16)
+ if bit.bxor(len,nlen) ~= 65535 then
+ error("LEN and NLEN don't match")
+ end
+ for i=1,len do
+ table.insert(out,bs:next_byte())
+ end
+end
+
+function inflate.main(bs)
+ local last,type
+ local output = {}
+ repeat
+ local block
+ last = bs:getb(1)
+ type = bs:getb(2)
+ if type == 0 then
+ block_uncompressed(output,bs)
+ elseif type == 1 then
+ block_static(output,bs)
+ elseif type == 2 then
+ block_dynamic(output,bs)
+ else
+ error("unsupported block type")
+ end
+ until last == 1
+ bs:flushb(bit.band(bs.n,7))
+ return output
+end
+
+local crc32_table
+function inflate.crc32(s,crc)
+ if not crc32_table then
+ crc32_table = {}
+ for i=0,255 do
+ local r=i
+ for j=1,8 do
+ r = bit.bxor(bit.rshift(r,1),bit.band(0xedb88320,bit.bnot(bit.band(r,1)-1)))
+ end
+ crc32_table[i] = r
+ end
+ end
+ crc = bit.bnot(crc or 0)
+ for i=1,#s do
+ local c = s:byte(i)
+ crc = bit.bxor(crc32_table[bit.bxor(c,bit.band(crc,0xff))],bit.rshift(crc,8))
+ end
+ crc = bit.bnot(crc)
+ if crc<0 then
+ -- in Lua < 5.2, sign extension was performed
+ crc = crc + 4294967296
+ end
+ return crc
+end
+
+return inflate