fixed_pool_eastl.cpp

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*/

// EASTL/fixed_pool.cpp
//
// Copyright (c) 2005, Electronic Arts. All rights reserved.
// Written and maintained by Paul Pedriana.



#include <stk_util/util/fixed_pool_eastl.h>
#include <stk_util/util/fixed_allocator_eastl.h>



namespace eastl
{


    void fixed_pool_base::init(void* pMemory, size_t memorySize, size_t nodeSize,
                               size_t alignment, size_t /*alignmentOffset*/)
    {
        // To do: Support alignmentOffset.

        #if EASTL_FIXED_SIZE_TRACKING_ENABLED
            mnCurrentSize = 0;
            mnPeakSize    = 0;
        #endif

        if(pMemory)
        {
            // Assert that alignment is a power of 2 value (e.g. 1, 2, 4, 8, 16, etc.)
            EASTL_ASSERT((alignment & (alignment - 1)) == 0);

            // Make sure alignment is a valid value.
            if(alignment < 1)
                alignment = 1;

            mpNext      = (Link*)(((uintptr_t)pMemory + (alignment - 1)) & ~(alignment - 1));
            memorySize -= (uintptr_t)mpNext - (uintptr_t)pMemory;
            pMemory     = mpNext;

            // The node size must be at least as big as a Link, which itself is sizeof(void*).
            if(nodeSize < sizeof(Link))
                nodeSize = ((sizeof(Link) + (alignment - 1))) & ~(alignment - 1);

            // If the user passed in a memory size that wasn't a multiple of the node size,
            // we need to chop down the memory size so that the last node is not a whole node.
            memorySize = (memorySize / nodeSize) * nodeSize;

            mpCapacity = (Link*)((uintptr_t)pMemory + memorySize);
            mpHead     = NULL;
            mnNodeSize = nodeSize;
        }
    }


} // namespace eastl