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74 lines
1.5 KiB
C
74 lines
1.5 KiB
C
/*
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* COPYRIGHT: See COPYING in the top level directory
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* PROJECT: ReactOS system libraries
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* FILE: lib/sdk/crt/stdlib/rot.c
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* PURPOSE: Performs a bitwise rotation
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* PROGRAMER: Ariadne
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* UPDATE HISTORY:
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* 03/04/99: Created
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*/
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#include <stdlib.h>
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#ifdef _MSC_VER
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#pragma function(_rotr, _rotl, _rotr, _lrotl, _lrotr)
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#endif
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unsigned int _rotr( unsigned int value, int shift );
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/*
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* @implemented
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*/
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unsigned int _rotl( unsigned int value, int shift )
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{
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int max_bits = sizeof(unsigned int)<<3;
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if ( shift < 0 )
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return _rotr(value,-shift);
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if ( shift > max_bits )
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shift = shift % max_bits;
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return (value << shift) | (value >> (max_bits-shift));
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}
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/*
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* @implemented
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*/
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unsigned int _rotr( unsigned int value, int shift )
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{
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int max_bits = sizeof(unsigned int)<<3;
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if ( shift < 0 )
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return _rotl(value,-shift);
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if ( shift > max_bits )
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shift = shift % max_bits;
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return (value >> shift) | (value << (max_bits-shift));
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}
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/*
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* @implemented
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*/
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unsigned long _lrotl( unsigned long value, int shift )
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{
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int max_bits = sizeof(unsigned long)<<3;
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if ( shift < 0 )
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return _lrotr(value,-shift);
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if ( shift > max_bits )
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shift = shift % max_bits;
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return (value << shift) | (value >> (max_bits-shift));
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}
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/*
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* @implemented
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*/
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unsigned long _lrotr( unsigned long value, int shift )
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{
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int max_bits = sizeof(unsigned long)<<3;
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if ( shift < 0 )
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return _lrotl(value,-shift);
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if ( shift > max_bits )
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shift = shift % max_bits;
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return (value >> shift) | (value << (max_bits-shift));
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}
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