__init__.c

// This file is part of the CircuitPython project: https://circuitpython.org
//
// SPDX-FileCopyrightText: Copyright (c) 2022 Mark Komus
//
// SPDX-License-Identifier: MIT

#include <stdint.h>
#include <assert.h>
#include <string.h>

#include "py/obj.h"
#include "py/runtime.h"
#include "py/stream.h"
#include "py/mperrno.h"
#include "py/builtin.h"
#include "py/objtuple.h"
#include "py/binary.h"
#include "py/parsenum.h"

#include "shared-bindings/zlib/__init__.h"

//| """zlib decompression functionality
//|
//| The `zlib` module allows limited functionality similar to the CPython zlib library.
//| This module allows to decompress binary data compressed with DEFLATE algorithm
//| (commonly used in zlib library and gzip archiver). Compression is not yet implemented."""
//|

//| def decompress(data: bytes, wbits: Optional[int] = 0, bufsize: Optional[int] = 0) -> bytes:
//|     """Return decompressed *data* as bytes. *wbits* is DEFLATE dictionary window
//|     size used during compression (8-15, the dictionary size is power of 2 of
//|     that value). Additionally, if value is positive, *data* is assumed to be
//|     zlib stream (with zlib header). Otherwise, if it's negative, it's assumed
//|     to be raw DEFLATE stream.
//|
//|     The wbits parameter controls the size of the history buffer (or “window size”), and what header
//|     and trailer format is expected.
//|
//|     Common wbits values:
//|
//|     * To decompress deflate format, use wbits = -15
//|     * To decompress zlib format, use wbits = 15
//|     * To decompress gzip format, use wbits = 31
//|
//|     :param bytes data: data to be decompressed
//|     :param int wbits: DEFLATE dictionary window size used during compression. See above.
//|     :param int bufsize: ignored for compatibility with CPython only
//|     """
//|     ...
//|
static mp_obj_t zlib_decompress(size_t n_args, const mp_obj_t *args) {
    mp_int_t wbits = 0;
    if (n_args > 1) {
        wbits = MP_OBJ_SMALL_INT_VALUE(args[1]);
    }

    return common_hal_zlib_decompress(args[0], wbits);
}
static MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(zlib_decompress_obj, 1, 3, zlib_decompress);

static const mp_rom_map_elem_t zlib_globals_table[] = {
    { MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_zlib) },
    { MP_ROM_QSTR(MP_QSTR_decompress), MP_ROM_PTR(&zlib_decompress_obj) },
};

static MP_DEFINE_CONST_DICT(zlib_globals, zlib_globals_table);

const mp_obj_module_t zlib_module = {
    .base = { &mp_type_module },
    .globals = (mp_obj_dict_t *)&zlib_globals,
};

MP_REGISTER_MODULE(MP_QSTR_zlib, zlib_module);