File indexing completed on 2024-05-19 14:56:23

 /*
 * Copyright (c) 2006-2009 Erin Catto http://www.box2d.org
 *
 * This software is provided 'as-is', without any express or implied
 * warranty.  In no event will the authors be held liable for any damages
 * arising from the use of this software.
 * Permission is granted to anyone to use this software for any purpose,
 * including commercial applications, and to alter it and redistribute it
 * freely, subject to the following restrictions:
 * 1. The origin of this software must not be misrepresented; you must not
 * claim that you wrote the original software. If you use this software
 * in a product, an acknowledgment in the product documentation would be
 * appreciated but is not required.
 * 2. Altered source versions must be plainly marked as such, and must not be
 * misrepresented as being the original software.
 * 3. This notice may not be removed or altered from any source distribution.
 */
 
 #include <Box2D/Common/b2StackAllocator.h>
 #include <Box2D/Common/b2Math.h>
 
 b2StackAllocator::b2StackAllocator()
 {
     m_index = 0;
     m_allocation = 0;
     m_maxAllocation = 0;
     m_entryCount = 0;
 }
 
 b2StackAllocator::~b2StackAllocator()
 {
     b2Assert(m_index == 0);
     b2Assert(m_entryCount == 0);
 }
 
 void* b2StackAllocator::Allocate(int32 size)
 {
     b2Assert(m_entryCount < b2_maxStackEntries);
 
     b2StackEntry* entry = m_entries + m_entryCount;
     entry->size = size;
     if (m_index + size > b2_stackSize)
     {
         entry->data = (char*)b2Alloc(size);
         entry->usedMalloc = true;
     }
     else
     {
         entry->data = m_data + m_index;
         entry->usedMalloc = false;
         m_index += size;
     }
 
     m_allocation += size;
     m_maxAllocation = b2Max(m_maxAllocation, m_allocation);
     ++m_entryCount;
 
     return entry->data;
 }
 
 void b2StackAllocator::Free(void* p)
 {
     b2Assert(m_entryCount > 0);
     b2StackEntry* entry = m_entries + m_entryCount - 1;
     b2Assert(p == entry->data);
     if (entry->usedMalloc)
     {
         b2Free(p);
     }
     else
     {
         m_index -= entry->size;
     }
     m_allocation -= entry->size;
     --m_entryCount;
 
     p = NULL;
 }
 
 int32 b2StackAllocator::GetMaxAllocation() const
 {
     return m_maxAllocation;
 }