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Date: Thu, 1 Sep 2022 11:54:30 +0100
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Subject: Re: [edk2-devel] [PATCH] [edk2-basetools]GenCrc32:Convert the C tool of calculating the crc32 into a python tool
To: devel@edk2.groups.io, wenzhao1.li@intel.com
Cc: Bob Feng <bob.c.feng@intel.com>, Liming Gao <gaoliming@byosoft.com.cn>,
 Yuwei Chen <yuwei.chen@intel.com>
References: <20220901065702.2412-1-wenzhao1.li@intel.com>
From: "Michael Brown" <mcb30@ipxe.org>
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On 01/09/2022 07:57, liwenzha wrote:
> This patch converts the C tool of calculating the crc32 value of file into
> a python file. To realize this,after reading the data into the file in
> binary form from an original file,a lookup table is listed to do XOR and
> shifting calculation for each bit in the file.

Python has binascii.crc32 as part of the standard library.  You can 
throw away the mCrcTable and all of the open-coded CRC32 calculation 
logic, and just do:

   from binascii import crc32

   CrcOut = crc32(filebytes)

HTH,

Michael