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- local lz = require "lzss"
- local buffer = require "buffer"
-
- lz16 = {}
-
- local function readBuffer(fi)
- local stream = {}
- if fi:read(4) ~= "lz16" then
- return false, "not an lz16 archive"
- end
- function stream.read()
- local len = string.unpack(">I2", fi:read(2) or "\0\0")
- if len < 1 then
- return nil
- end
- if os.sleep then os.sleep(0) else coroutine.yield() end
- return lz.decompress(fi:read(len))
- end
- function stream.close()
- fi:close()
- end
- return buffer.new("rb",stream)
- end
-
- local function writeBuffer(fo)
- local stream = {}
- function stream:write(data)
- local cblock = lz.compress(data)
- fo:write(string.pack(">I2", cblock:len()) .. cblock)
- return cblock:len()+2
- end
- function stream.close()
- fo:close()
- end
- fo:write("lz16") -- write header
- return buffer.new("wb",stream)
- end
-
- function lz16.buffer(stream) -- table -- table -- Wrap a stream to read or write LZ16.
- if stream.mode.w then
- return writeBuffer(stream)
- end
- return readBuffer(stream)
- end
-
- function lz16.open(fname, mode) -- string string -- table -- Open file *fname* to read or write LZ16-compressed data depending on *mode*
- local f = io.open(fname, mode)
- if not f then return false end
- f.mode.b = true
- return lz16.buffer(f)
- end
-
- return lz16
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