postgresql/src/backend/lib/bit.c

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/*-------------------------------------------------------------------------
*
* bit.c--
* Standard bit array code.
*
* Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/lib/Attic/bit.c,v 1.1.1.1 1996/07/09 06:21:28 scrappy Exp $
*
*-------------------------------------------------------------------------
*/
/*
* utils/memutils.h contains declarations of the functions in this file
*/
#include "utils/memutils.h"
void
BitArraySetBit(BitArray bitArray, BitIndex bitIndex)
{
bitArray[bitIndex/BitsPerByte]
|= (1 << (BitsPerByte - (bitIndex % BitsPerByte) - 1));
return;
}
void
BitArrayClearBit(BitArray bitArray, BitIndex bitIndex)
{
bitArray[bitIndex/BitsPerByte]
&= ~(1 << (BitsPerByte - (bitIndex % BitsPerByte) - 1));
return;
}
bool
BitArrayBitIsSet(BitArray bitArray, BitIndex bitIndex)
{
return( (bool) (((bitArray[bitIndex / BitsPerByte] &
(1 << (BitsPerByte - (bitIndex % BitsPerByte)
- 1)
)
) != 0 ) ? 1 : 0) );
}