xash3d-fwgs/vgui_support/utlmemory.h

369 lines
8.5 KiB
C++

//=========== (C) Copyright 1999 Valve, L.L.C. All rights reserved. ===========
//
// The copyright to the contents herein is the property of Valve, L.L.C.
// The contents may be used and/or copied only with the written permission of
// Valve, L.L.C., or in accordance with the terms and conditions stipulated in
// the agreement/contract under which the contents have been supplied.
//
// $Header: $
// $NoKeywords: $
//
// A growable memory class.
//=============================================================================
#ifndef UTLMEMORY_H
#define UTLMEMORY_H
#ifdef _WIN32
#pragma once
#endif
#include "port.h"
#include <string.h>
#ifdef NO_STL
template <class T>
void *operator new(size_t count, T *ptr) {
return ptr;
}
#elif defined _WIN32
#include <new.h>
#else
#include <new>
#endif
#include <stdlib.h>
#include <math.h>
//-----------------------------------------------------------------------------
// Methods to invoke the constructor, copy constructor, and destructor
//-----------------------------------------------------------------------------
template <class T>
inline void Construct( T* pMemory )
{
new( pMemory ) T;
}
template <class T>
inline void CopyConstruct( T* pMemory, T const& src )
{
new( pMemory ) T(src);
}
template <class T>
inline void Destruct( T* pMemory )
{
pMemory->~T();
#ifdef _DEBUG
memset( pMemory, 0xDD, sizeof(T) );
#endif
}
#pragma warning (disable:4100)
#pragma warning (disable:4514)
//-----------------------------------------------------------------------------
// The CUtlMemory class:
// A growable memory class which doubles in size by default.
//-----------------------------------------------------------------------------
template< class T >
class CUtlMemory
{
public:
// constructor, destructor
CUtlMemory( int nGrowSize = 0, int nInitSize = 0 );
CUtlMemory( T* pMemory, int numElements );
~CUtlMemory();
// element access
T& operator[]( int i );
T const& operator[]( int i ) const;
T& Element( int i );
T const& Element( int i ) const;
// Can we use this index?
bool IsIdxValid( int i ) const;
// Gets the base address (can change when adding elements!)
T* Base();
T const* Base() const;
// Attaches the buffer to external memory....
void SetExternalBuffer( T* pMemory, int numElements );
// Size
int NumAllocated() const;
int Count() const;
// Grows the memory, so that at least allocated + num elements are allocated
void Grow( int num = 1 );
// Makes sure we've got at least this much memory
void EnsureCapacity( int num );
// Memory deallocation
void Purge();
// is the memory externally allocated?
bool IsExternallyAllocated() const;
// Set the size by which the memory grows
void SetGrowSize( int size );
private:
enum
{
EXTERNAL_BUFFER_MARKER = -1
};
T* m_pMemory;
int m_nAllocationCount;
int m_nGrowSize;
};
//-----------------------------------------------------------------------------
// constructor, destructor
//-----------------------------------------------------------------------------
template< class T >
CUtlMemory<T>::CUtlMemory( int nGrowSize, int nInitAllocationCount ) : m_pMemory(0),
m_nAllocationCount( nInitAllocationCount ), m_nGrowSize( nGrowSize )
{
Assert( (nGrowSize >= 0) && (nGrowSize != EXTERNAL_BUFFER_MARKER) );
if (m_nAllocationCount)
{
m_pMemory = (T*)malloc( m_nAllocationCount * sizeof(T) );
}
}
template< class T >
CUtlMemory<T>::CUtlMemory( T* pMemory, int numElements ) : m_pMemory(pMemory),
m_nAllocationCount( numElements )
{
// Special marker indicating externally supplied memory
m_nGrowSize = EXTERNAL_BUFFER_MARKER;
}
template< class T >
CUtlMemory<T>::~CUtlMemory()
{
Purge();
}
//-----------------------------------------------------------------------------
// Attaches the buffer to external memory....
//-----------------------------------------------------------------------------
template< class T >
void CUtlMemory<T>::SetExternalBuffer( T* pMemory, int numElements )
{
// Blow away any existing allocated memory
Purge();
m_pMemory = pMemory;
m_nAllocationCount = numElements;
// Indicate that we don't own the memory
m_nGrowSize = EXTERNAL_BUFFER_MARKER;
}
//-----------------------------------------------------------------------------
// element access
//-----------------------------------------------------------------------------
template< class T >
inline T& CUtlMemory<T>::operator[]( int i )
{
Assert( IsIdxValid(i) );
return m_pMemory[i];
}
template< class T >
inline T const& CUtlMemory<T>::operator[]( int i ) const
{
Assert( IsIdxValid(i) );
return m_pMemory[i];
}
template< class T >
inline T& CUtlMemory<T>::Element( int i )
{
Assert( IsIdxValid(i) );
return m_pMemory[i];
}
template< class T >
inline T const& CUtlMemory<T>::Element( int i ) const
{
Assert( IsIdxValid(i) );
return m_pMemory[i];
}
//-----------------------------------------------------------------------------
// is the memory externally allocated?
//-----------------------------------------------------------------------------
template< class T >
bool CUtlMemory<T>::IsExternallyAllocated() const
{
return m_nGrowSize == EXTERNAL_BUFFER_MARKER;
}
template< class T >
void CUtlMemory<T>::SetGrowSize( int nSize )
{
Assert( (nSize >= 0) && (nSize != EXTERNAL_BUFFER_MARKER) );
m_nGrowSize = nSize;
}
//-----------------------------------------------------------------------------
// Gets the base address (can change when adding elements!)
//-----------------------------------------------------------------------------
template< class T >
inline T* CUtlMemory<T>::Base()
{
return m_pMemory;
}
template< class T >
inline T const* CUtlMemory<T>::Base() const
{
return m_pMemory;
}
//-----------------------------------------------------------------------------
// Size
//-----------------------------------------------------------------------------
template< class T >
inline int CUtlMemory<T>::NumAllocated() const
{
return m_nAllocationCount;
}
template< class T >
inline int CUtlMemory<T>::Count() const
{
return m_nAllocationCount;
}
//-----------------------------------------------------------------------------
// Is element index valid?
//-----------------------------------------------------------------------------
template< class T >
inline bool CUtlMemory<T>::IsIdxValid( int i ) const
{
return (i >= 0) && (i < m_nAllocationCount);
}
//-----------------------------------------------------------------------------
// Grows the memory
//-----------------------------------------------------------------------------
template< class T >
void CUtlMemory<T>::Grow( int num )
{
Assert( num > 0 );
if (IsExternallyAllocated())
{
// Can't grow a buffer whose memory was externally allocated
Assert(0);
return;
}
// Make sure we have at least numallocated + num allocations.
// Use the grow rules specified for this memory (in m_nGrowSize)
int nAllocationRequested = m_nAllocationCount + num;
while (m_nAllocationCount < nAllocationRequested)
{
if ( m_nAllocationCount != 0 )
{
if (m_nGrowSize)
{
m_nAllocationCount += m_nGrowSize;
}
else
{
m_nAllocationCount += m_nAllocationCount;
}
}
else
{
// Compute an allocation which is at least as big as a cache line...
m_nAllocationCount = (31 + sizeof(T)) / sizeof(T);
Assert(m_nAllocationCount != 0);
}
}
if (m_pMemory)
{
T* pTempMemory = ( T* )realloc( m_pMemory, m_nAllocationCount * sizeof( T ) );
if( !pTempMemory )
return;
m_pMemory = pTempMemory;
}
else
{
m_pMemory = (T*)malloc( m_nAllocationCount * sizeof(T) );
}
}
//-----------------------------------------------------------------------------
// Makes sure we've got at least this much memory
//-----------------------------------------------------------------------------
template< class T >
inline void CUtlMemory<T>::EnsureCapacity( int num )
{
if (m_nAllocationCount >= num)
return;
if (IsExternallyAllocated())
{
// Can't grow a buffer whose memory was externally allocated
Assert(0);
return;
}
m_nAllocationCount = num;
if (m_pMemory)
{
T* pTempMemory = ( T* )realloc( m_pMemory, m_nAllocationCount * sizeof( T ) );
if( !pTempMemory )
return;
m_pMemory = pTempMemory;
}
else
{
m_pMemory = (T*)malloc( m_nAllocationCount * sizeof(T) );
}
}
//-----------------------------------------------------------------------------
// Memory deallocation
//-----------------------------------------------------------------------------
template< class T >
void CUtlMemory<T>::Purge()
{
if (!IsExternallyAllocated())
{
if (m_pMemory)
{
free( (void*)m_pMemory );
m_pMemory = 0;
}
m_nAllocationCount = 0;
}
}
#endif//UTLMEMORY_H