ArenaBlock.hpp

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/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#if !defined(ARENABLOCK_INCLUDE_GUARD_1357924680)
#define ARENABLOCK_INCLUDE_GUARD_1357924680



#include <xalanc/PlatformSupport/ArenaBlockBase.hpp>




XALAN_CPP_NAMESPACE_BEGIN


template<class ObjectType,
#if defined(XALAN_NO_DEFAULT_TEMPLATE_ARGUMENTS)
         class SizeType>
#else
         class SizeType = size_t>
#endif
class ArenaBlock : public ArenaBlockBase<ObjectType, SizeType>
{
public:

    typedef ArenaBlockBase<ObjectType, SizeType>    BaseClassType;

    typedef ArenaBlock<ObjectType, SizeType>        ThisType;

    typedef typename BaseClassType::size_type       size_type;

    /*
     * Construct an ArenaBlock of the specified size
     * of objects.
     *
     * @param theManager The memory manager instance for the block.
     * @param theBlockSize The size of the block (the number of objects it can contain).
     */
    ArenaBlock(
                MemoryManager&  theManager,
                size_type           theBlockSize) : 
        BaseClassType(theManager, theBlockSize)
    {
    }

    ~ArenaBlock()
    {   
        assert( this->m_objectCount <= this->m_blockSize );
        
        for ( size_type i = 0; i < this->m_objectCount  ; ++i )
        {
            XalanDestroy(this->m_objectBlock[i]);
        }
    }

    static ThisType*
    create(
                MemoryManager&  theManager,
                size_type           theBlockSize)
    {
        ThisType* theInstance;

        return XalanConstruct(
                    theManager,
                    theInstance,
                    theManager,
                    theBlockSize);
    }

    /*
     * Allocate a block.  Once the object is constructed, you must call
     * commitAllocation().
     *
     * @return a pointer to the new block.
     */
    ObjectType*
    allocateBlock()
    {
        // Any space left?
        if (this->m_objectCount == this->m_blockSize)
        {
            return 0;
        }
        else
        {
            assert(this->m_objectBlock != 0);

            return this->m_objectBlock + this->m_objectCount;
        }
    }

    /*
     * Commit the previous allocation.
     *
     * @param theBlock the address that was returned by allocateBlock()
     */
    void
#if defined (NDEBUG)
    commitAllocation(ObjectType*    /* theBlock */)
#else
    commitAllocation(ObjectType*    theBlock)
#endif
    {
        assert(theBlock == this->m_objectBlock + this->m_objectCount);
        assert(this->m_objectCount < this->m_blockSize);

        ++this->m_objectCount;
    }

    /*
     * Determine if this block owns the specified object.  Note
     * that even if the object address is within our block, this
     * call will return false if no object currently occupies the
     * block.  See also ownsBlock().
     *
     * @param theObject the address of the object.
     * @return true if we own the object, false if not.
     */
    bool
    ownsObject(const ObjectType*    theObject) const
    {
        return this->isInBorders(theObject, this->m_objectCount);
    }

private:

    // Not implemented...
    ArenaBlock(const ArenaBlock<ObjectType, SizeType>&);

    ArenaBlock<ObjectType, SizeType>&
    operator=(const ArenaBlock<ObjectType, SizeType>&);

    bool
    operator==(const ArenaBlock<ObjectType, SizeType>&) const;
};



XALAN_CPP_NAMESPACE_END



#endif  // !defined(ARENABLOCK_INCLUDE_GUARD_1357924680)