Merge pull request #5969 from Life-Imaging-Services/crc32

crc32() code moved into binascii
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Dan Halbert 2022-02-02 18:07:02 -05:00 committed by GitHub
commit 0129735dbe
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2 changed files with 66 additions and 6 deletions

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@ -1,5 +1,6 @@
// Copyright (c) 2014 Paul Sokolovsky
// SPDX-FileCopyrightText: 2014 MicroPython & CircuitPython contributors (https://github.com/adafruit/circuitpython/graphs/contributors)
// SPDX-FileCopyrightText: 2022 Beat Ludin for Adafruit Industries
//
// SPDX-License-Identifier: MIT
@ -204,19 +205,78 @@ STATIC mp_obj_t mod_binascii_b2a_base64(mp_obj_t data) {
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_binascii_b2a_base64_obj, mod_binascii_b2a_base64);
#if MICROPY_PY_UBINASCII_CRC32
#include "lib/uzlib/tinf.h"
/*
* CRC32 checksum
*
* Copyright (c) 1998-2003 by Joergen Ibsen / Jibz
* All Rights Reserved
*
* http://www.ibsensoftware.com/
*
* This software is provided 'as-is', without any express
* or implied warranty. In no event will the authors be
* held liable for any damages arising from the use of
* this software.
*
* Permission is granted to anyone to use this software
* for any purpose, including commercial applications,
* and to alter it and redistribute it freely, subject to
* the following restrictions:
*
* 1. The origin of this software must not be
* misrepresented; you must not claim that you
* wrote the original software. If you use this
* software in a product, an acknowledgment in
* the product documentation would be appreciated
* but is not required.
*
* 2. Altered source versions must be plainly marked
* as such, and must not be misrepresented as
* being the original software.
*
* 3. This notice may not be removed or altered from
* any source distribution.
*/
/*
* CRC32 algorithm taken from the zlib source, which is
* Copyright (C) 1995-1998 Jean-loup Gailly and Mark Adler
*/
static const unsigned int tinf_crc32tab[16] = {
0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac, 0x76dc4190,
0x6b6b51f4, 0x4db26158, 0x5005713c, 0xedb88320, 0xf00f9344,
0xd6d6a3e8, 0xcb61b38c, 0x9b64c2b0, 0x86d3d2d4, 0xa00ae278,
0xbdbdf21c
};
/* crc is previous value for incremental computation, 0xffffffff initially */
static uint32_t from_uzlib_crc32(const void *data, unsigned int length, uint32_t crc) {
const unsigned char *buf = (const unsigned char *)data;
unsigned int i;
for (i = 0; i < length; ++i)
{
crc ^= buf[i];
crc = tinf_crc32tab[crc & 0x0f] ^ (crc >> 4);
crc = tinf_crc32tab[crc & 0x0f] ^ (crc >> 4);
}
// return value suitable for passing in next time, for final value invert it
return crc /* ^ 0xffffffff*/;
}
STATIC mp_obj_t mod_binascii_crc32(size_t n_args, const mp_obj_t *args) {
mp_buffer_info_t bufinfo;
check_not_unicode(args[0]);
mp_get_buffer_raise(args[0], &bufinfo, MP_BUFFER_READ);
uint32_t crc = (n_args > 1) ? mp_obj_get_int_truncated(args[1]) : 0;
crc = uzlib_crc32(bufinfo.buf, bufinfo.len, crc ^ 0xffffffff);
crc = from_uzlib_crc32(bufinfo.buf, bufinfo.len, crc ^ 0xffffffff);
return mp_obj_new_int_from_uint(crc ^ 0xffffffff);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mod_binascii_crc32_obj, 1, 2, mod_binascii_crc32);
#endif
STATIC const mp_rom_map_elem_t mp_module_binascii_globals_table[] = {
{ MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_binascii) },
@ -224,9 +284,7 @@ STATIC const mp_rom_map_elem_t mp_module_binascii_globals_table[] = {
{ MP_ROM_QSTR(MP_QSTR_unhexlify), MP_ROM_PTR(&mod_binascii_unhexlify_obj) },
{ MP_ROM_QSTR(MP_QSTR_a2b_base64), MP_ROM_PTR(&mod_binascii_a2b_base64_obj) },
{ MP_ROM_QSTR(MP_QSTR_b2a_base64), MP_ROM_PTR(&mod_binascii_b2a_base64_obj) },
#if MICROPY_PY_UBINASCII_CRC32
{ MP_ROM_QSTR(MP_QSTR_crc32), MP_ROM_PTR(&mod_binascii_crc32_obj) },
#endif
};
STATIC MP_DEFINE_CONST_DICT(mp_module_binascii_globals, mp_module_binascii_globals_table);

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@ -9,3 +9,5 @@ CHIP_FAMILY = samd21
INTERNAL_FLASH_FILESYSTEM = 1
LONGINT_IMPL = NONE
CIRCUITPY_FULL_BUILD = 0
CIRCUITPY_ONEWIREIO = 0