*************************************************************************
* Author    : Tiago Dionizio <tiago.dionizio@gmail.com>                 *
* Library   : lzlib - Lua 5.1 interface to access zlib library functions*
*                                                                       *
* Permission is hereby granted, free of charge, to any person obtaining *
* a copy of this software and associated documentation files (the       *
* "Software"), to deal in the Software without restriction, including   *
* without limitation the rights to use, copy, modify, merge, publish,   *
* distribute, sublicense, and/or sell copies of the Software, and to    *
* permit persons to whom the Software is furnished to do so, subject to *
* the following conditions:                                             *
*                                                                       *
* The above copyright notice and this permission notice shall be        *
* included in all copies or substantial portions of the Software.       *
*                                                                       *
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       *
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    *
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*
* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  *
* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  *
* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     *
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                *
*************************************************************************

To use this library you need zlib library.
You can get it from http://www.gzip.org/zlib/


Loading the library:

    If you built the library as a loadable package
        [local] zlib = require 'zlib'

    If you compiled the package statically into your application, call
    the function "luaopen_zlib(L)". It will create a table with the zlib
    functions and leave it on the stack.

Definitions:

    ds  = deflate stream
    is  = inflate stream
    int = number (integer)
    *   = (any type)

    [...] represent optional parameters that may be omited or nil, in wich case
    will be replaced by their default values

-- zlib functions --

string      zlib.version()
int         zlib.compile_flags()
int         zlib.adler32(int adler, string buf)
int         zlib.crc32(int crc, string buf)

string      zlib.compress(string buf [, int level] [, int method] [, int windowBits] [, int memLevel] [, int strategy])
string      zlib.uncompress(string buf [, int windowBits])

ds          zlib.deflate_init([int level] [, int method] [, int windowBits] [, int memLevel] [, int strategy])
is          zlib.inflate_init([int windowBits])

-- deflate stream methods --

int         ds:adler()
int         ds:data_type()
int         ds:total_in()
int         ds:total_out()
int, int    df:process(string [, int flush])
void        ds:done()
void        ds:callback(function callback, * userdata)
int         ds:set_dictionary(string dictionary)
ds [,int]   ds:clone()
int         ds:reset()
int         ds:params(int level, int strategy)
int         ds:prime(int bits, int value)

-- inflate stream methods --

int         is:adler()
int         is:data_type()
int         is:total_in()
int         is:total_out()
int, int    if:process(string [, int flush])
void        if:done()
void        is:callback([function callback] [, * userdata])
void        is:dictionary([function callback] [, * userdata])
int         is:set_dictionary(string dictionary)
is [,int]   is:clone()
int         is:reset()
int, int    is:sync(string buf)

-- callbacks --
void        callback(string buf, * userdata)
void        dictionary(* userdata)

-- general description --
most functions/methods correspond to the original function in the zlib
library, the main differences are:

when (de)compressing blocks, the generated output is sent to the callback
function, this is done to prevent passing too much meaningful result values
from the process method

deflate/inflate zlib functions are interfaced through the process method

ds:params may invoke the output callback

process method returns the error value and the number of input bytes
processed

clone method returns a copy of the stream (also copies callbacks) and
returns a new stream object or nil plus an error code

dictionary callback is not strictly necessary, but may avoid extra process
calls if used, only needed when compressed stream also used a custom
dictionary. when using it you must call is:set_dictionary as needed, if not
you will have to watch the return code for zlib.

is:sync returns an error code and the number of input bytes processed


** for more information please refer to zlib.h **