gecko-dev/js/tamarin/MMgc/GCStack.h

129 строки
3.2 KiB
C++

/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is [Open Source Virtual Machine.].
*
* The Initial Developer of the Original Code is
* Adobe System Incorporated.
* Portions created by the Initial Developer are Copyright (C) 2004-2006
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Adobe AS3 Team
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#ifndef __GCStack__
#define __GCStack__
namespace MMgc
{
template<typename T, int defSize=512>
class GCStack
{
enum { kDefSize = defSize };
public:
GCStack(int defaultSize=kDefSize) : m_iCount(0), m_iAllocSize(defaultSize), m_items(NULL)
{
Alloc();
}
~GCStack()
{
if ( m_items )
{
delete [] m_items;
m_items = NULL;
}
m_iCount = m_iAllocSize = 0;
}
void Push(T item)
{
if ( ( m_iCount + 1 ) > m_iAllocSize )
{
// need to allocate a new block first
m_iAllocSize = m_iAllocSize ? m_iAllocSize*2 : kDefSize;
Alloc();
}
m_items[m_iCount++] = item;
}
T Pop()
{
T t = m_items[--m_iCount];
#ifdef _DEBUG
GCAssert(m_iCount>=0);
memset(&m_items[m_iCount], 0, sizeof(T));
#endif
return t;
}
T Peek()
{
#ifdef _DEBUG
GCAssert(m_iCount>=0);
#endif
T t = m_items[m_iCount-1];
return t;
}
unsigned int Count() { return m_iCount; }
void Keep(unsigned int num)
{
GCAssert(num <= m_iCount);
m_iCount = num;
}
T* GetData() { return m_items; }
protected:
// no impl
GCStack(const GCStack& other);
GCStack& operator=(const GCStack& other);
private:
void Alloc()
{
// need to allocate a new block first
if(m_iAllocSize) {
T* items = new T[ m_iAllocSize ];
if ( items )
{
::memcpy(items, m_items, m_iCount * sizeof(T));
}
delete [] m_items;
m_items = items;
}
}
unsigned int m_iCount, m_iAllocSize;
T *m_items;
};
}
#endif /* __GCStack__ */