windows-nt/Source/XPSP1/NT/com/rpc/runtime/mtrt/bitset.cxx
2020-09-26 16:20:57 +08:00

105 lines
2.4 KiB
C++

//+-------------------------------------------------------------------------
//
// Microsoft Windows
//
// Copyright (C) Microsoft Corporation, 1990 - 1999
//
// File: bitset.cxx
//
//--------------------------------------------------------------------------
/* --------------------------------------------------------------------
Microsoft OS/2 LAN Manager
Copyright(c) Microsoft Corp., 1990
-------------------------------------------------------------------- */
/* --------------------------------------------------------------------
File : bitset.cxx
Title : Bit vector implementation of a set.
History :
mikemon ??-??-?? Beginning of recorded history.
mikemon 11-13-90 Commented the source.
-------------------------------------------------------------------- */
#include <precomp.hxx>
#include <bitset.hxx>
int
BITSET::Insert (
IN int Key
)
{
unsigned int * pNewBits;
int cCount;
//
// Check if the Key will fit into the current bit vector.
//
if ((int) ((Key/(sizeof(int)*8))+1) > cBits)
{
//
// We need more space in the bit vector, so allocate enough space
// to hold the bit for the specified key, copy the old bit vector into the
// new bit vector, and then free the old one.
//
pNewBits = new unsigned int [Key/(sizeof(int)*8)+1];
if (pNewBits == (unsigned int *) 0)
return(1);
for (cCount = 0; cCount < cBits; cCount++)
pNewBits[cCount] = pBits[cCount];
cBits = Key/(sizeof(int)*8) + 1;
for ( ; cCount < cBits; cCount++)
pNewBits[cCount] = 0;
if (pBits != &InitialStorage)
delete pBits;
pBits = pNewBits;
}
//
// Turn on the appropriate bit, by ORing it in.
//
pBits[Key/(sizeof(int)*8)] |= (1 << (Key % (sizeof(int)*8)));
return(0);
}
void
BITSET::Delete (
IN int Key
)
{
if ((int) (Key/(sizeof(int)*8)) > cBits-1)
return;
//
// Turn off the appropriate bit, by ANDing in the complement.
//
pBits[Key/(sizeof(int)*8)] &= ~(1 << (Key % (sizeof(int)*8)));
}
int
BITSET::MemberP (
IN int Key
)
{
if ((int) (Key/(sizeof(int)*8)) > cBits-1)
return(0);
//
// Test for the appropriate bit
//
return(((pBits[Key/(sizeof(int)*8)]
& (1 << (Key % (sizeof(int)*8)))) ? 1 : 0));
}