source-engine/tier1/utlbinaryblock.cpp

//====== Copyright 1996-2004, Valve Corporation, All rights reserved. =======
//
// Purpose: 
//
//=============================================================================

#include "tier1/utlbinaryblock.h"

//-----------------------------------------------------------------------------
// Base class, containing simple memory management
//-----------------------------------------------------------------------------
CUtlBinaryBlock::CUtlBinaryBlock( int growSize, int initSize ) : m_Memory( growSize, initSize )
{
	m_nActualLength = 0;
}

CUtlBinaryBlock::CUtlBinaryBlock( void* pMemory, int nSizeInBytes, int nInitialLength ) : m_Memory( (unsigned char*)pMemory, nSizeInBytes )
{
	m_nActualLength = nInitialLength;
}

CUtlBinaryBlock::CUtlBinaryBlock( const void* pMemory, int nSizeInBytes ) : m_Memory( (const unsigned char*)pMemory, nSizeInBytes )
{
	m_nActualLength = nSizeInBytes;
}

CUtlBinaryBlock::CUtlBinaryBlock( const CUtlBinaryBlock& src )
{
	Set( src.Get(), src.Length() );
}

void CUtlBinaryBlock::Get( void *pValue, int nLen ) const
{
	Assert( nLen > 0 );
	if ( m_nActualLength < nLen )
	{
		nLen = m_nActualLength;
	}

	if ( nLen > 0 )
	{
		memcpy( pValue, m_Memory.Base(), nLen );
	}
}

void CUtlBinaryBlock::SetLength( int nLength )
{
	Assert( !m_Memory.IsReadOnly() );

	m_nActualLength = nLength;
	if ( nLength > m_Memory.NumAllocated() )
	{
		int nOverFlow = nLength - m_Memory.NumAllocated();
		m_Memory.Grow( nOverFlow );

		// If the reallocation failed, clamp length
		if ( nLength > m_Memory.NumAllocated() )
		{
			m_nActualLength = m_Memory.NumAllocated();
		}
	}

#ifdef _DEBUG
	if ( m_Memory.NumAllocated() > m_nActualLength )
	{
		memset( ( ( char * )m_Memory.Base() ) + m_nActualLength, 0xEB, m_Memory.NumAllocated() - m_nActualLength );
	}
#endif
}


void CUtlBinaryBlock::Set( const void *pValue, int nLen )
{
	Assert( !m_Memory.IsReadOnly() );

	if ( !pValue )
	{
		nLen = 0;
	}

	SetLength( nLen );

	if ( m_nActualLength )
	{
		if ( ( ( const char * )m_Memory.Base() ) >= ( ( const char * )pValue ) + nLen ||
			 ( ( const char * )m_Memory.Base() ) + m_nActualLength <= ( ( const char * )pValue ) )
		{
			memcpy( m_Memory.Base(), pValue, m_nActualLength );
		}
		else
		{
			memmove( m_Memory.Base(), pValue, m_nActualLength );
		}
	}
}


CUtlBinaryBlock &CUtlBinaryBlock::operator=( const CUtlBinaryBlock &src )
{
	Assert( !m_Memory.IsReadOnly() );
	Set( src.Get(), src.Length() );
	return *this;
}


bool CUtlBinaryBlock::operator==( const CUtlBinaryBlock &src ) const
{
	if ( src.Length() != Length() )
		return false;

	return !memcmp( src.Get(), Get(), Length() );
}