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Fix crc32 duplication

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This commit is contained in:
Jeff Epler 2023-09-22 13:38:17 -05:00
parent 6b5c7b6ce6
commit 23ad19fc5c
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1 changed files with 2 additions and 29 deletions
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31
extmod/modubinascii.c
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@ -32,6 +32,8 @@
#include "py/binary.h"
#include "py/objstr.h"
#include "lib/uzlib/tinf.h"
#if MICROPY_PY_UBINASCII
static void check_not_unicode(const mp_obj_t arg) {
@ -217,35 +219,6 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_KW(mod_binascii_b2a_base64_obj, 1, mod_binascii_b
* 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*/;
}
#if MICROPY_PY_UBINASCII_CRC32
STATIC mp_obj_t mod_binascii_crc32(size_t n_args, const mp_obj_t *args) {
mp_buffer_info_t bufinfo;