arena.cpp

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/* Copyright (c) 2011 Wildfire Games
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

/*
 * arena allocator (variable-size blocks, no deallocation).
 */

#include "precompiled.h"
#include "lib/allocators/arena.h"

namespace Allocators {

template<class Storage>
struct BasicArenaTest
{
    void operator()() const
    {
        Arena<Storage> a(100);
        const size_t initialSpace = a.RemainingBytes();
        void* p = a.allocate(100);
        ENSURE(p != 0);
        ENSURE(a.Contains(uintptr_t(p)));
        ENSURE(a.RemainingBytes() == initialSpace-100);
        ENSURE(a.Contains(uintptr_t(p)+1));
        ENSURE(a.Contains(uintptr_t(p)+99));
        ENSURE(!a.Contains(uintptr_t(p)-1));
        ENSURE(!a.Contains(uintptr_t(p)+100));
        if(a.RemainingBytes() == 0)
            ENSURE(a.allocate(1) == 0); // full
        else
            ENSURE(a.allocate(1) != 0); // can still expand
        a.DeallocateAll();
        ENSURE(!a.Contains(uintptr_t(p)));

        p = a.allocate(36);
        ENSURE(p != 0);
        ENSURE(a.Contains(uintptr_t(p)));
        ENSURE(a.RemainingBytes() == initialSpace-36);
        void* p2 = a.allocate(64);
        ENSURE(p2 != 0);
        ENSURE(a.Contains(uintptr_t(p2)));
        ENSURE(a.RemainingBytes() == initialSpace-36-64);
        ENSURE(p2 == (void*)(uintptr_t(p)+36));
        if(a.RemainingBytes() == 0)
            ENSURE(a.allocate(1) == 0); // full
        else
            ENSURE(a.allocate(1) != 0); // can still expand
    }
};

void TestArena()
{
    ForEachStorage<BasicArenaTest>();
}

}   // namespace Allocators