open-ath9k-htc-firmware/target_firmware/firmware-crc.pl

#!/usr/bin/env perl
##
 # Copyright (c) 2013 Qualcomm Atheros, Inc.
 #
 # All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted (subject to the limitations in the
 # disclaimer below) provided that the following conditions are met:
 #
 #  * Redistributions of source code must retain the above copyright
 #    notice, this list of conditions and the following disclaimer.
 #
 #  * Redistributions in binary form must reproduce the above copyright
 #    notice, this list of conditions and the following disclaimer in the
 #    documentation and/or other materials provided with the
 #    distribution.
 #
 #  * Neither the name of Qualcomm Atheros nor the names of its
 #    contributors may be used to endorse or promote products derived
 #    from this software without specific prior written permission.
 #
 # NO EXPRESS OR IMPLIED LICENSES TO ANY PARTY'S PATENT RIGHTS ARE
 # GRANTED BY THIS LICENSE.  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT
 # HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED
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 ##

use strict;
my $crc = 0;
my $bytes;
my $buf;
while (($bytes = read(STDIN, $buf, 4)) == 4) {
	print $buf;
	my $v = unpack("N", $buf);
	$crc = $crc ^ $v;
}
print pack("N", $crc);