//GNU Library General Public License (LGPL)
//http://dac.codeplex.com/license
using System;
using System.Security;
namespace RaisingStudio.Collections.Generic
{
internal class BitHelper
{
private const byte IntSize = 0x20;
private int[] m_array;
private unsafe int* m_arrayPtr;
private int m_length;
private const byte MarkedBitFlag = 1;
private bool useStackAlloc;
#if (PocketPC || Smartphone)
#else
[SecurityCritical]
#endif
internal unsafe BitHelper(int* bitArrayPtr, int length)
{
this.m_arrayPtr = bitArrayPtr;
this.m_length = length;
this.useStackAlloc = true;
}
internal BitHelper(int[] bitArray, int length)
{
this.m_array = bitArray;
this.m_length = length;
}
[SecurityCritical]
internal unsafe bool IsMarked(int bitPosition)
{
if (this.useStackAlloc)
{
int num = bitPosition / 0x20;
return (((num < this.m_length) && (num >= 0)) && ((this.m_arrayPtr[num] & (((int)1) << (bitPosition % 0x20))) != 0));
}
int index = bitPosition / 0x20;
return (((index < this.m_length) && (index >= 0)) && ((this.m_array[index] & (((int)1) << (bitPosition % 0x20))) != 0));
}
[SecurityCritical]
internal unsafe void MarkBit(int bitPosition)
{
if (this.useStackAlloc)
{
int num = bitPosition / 0x20;
if ((num < this.m_length) && (num >= 0))
{
int* numPtr1 = this.m_arrayPtr + num;
numPtr1[0] |= ((int)1) << (bitPosition % 0x20);
}
}
else
{
int index = bitPosition / 0x20;
if ((index < this.m_length) && (index >= 0))
{
this.m_array[index] |= ((int)1) << (bitPosition % 0x20);
}
}
}
internal static int ToIntArrayLength(int n)
{
if (n <= 0)
{
return 0;
}
return (((n - 1) / 0x20) + 1);
}
}
}
|
