pool.hpp

来自「开放源码的编译器open watcom 1.6.0版的源代码」· HPP 代码 · 共 102 行

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#ifndef _POOL_HPP
#define _POOL_HPP

#define POOL_START      256
#define POOL_INC        256

//
// Pool         --Data allocation class (i.e. a carver).
//

enum    PoolIds {       // for debugging
    AvlLinkPool = 0x00,
    AvlStackPool,
    DeclPool,
    DefnPool,
    HashLinkPool,
    LListBlockPool,
    U32PairPool,
    ScopePool,
    StrLinkPool,
    TypePool,
    UsagePool
};

class Pool {
    private:
        static const unsigned   BLOCK_LEN;

    public:
        Pool( PoolIds id, size_t size, unsigned blockLen=BLOCK_LEN );
        ~Pool();

        void *Get();
        void Release( void * p );

        enum Severity {
            Low,        // Organize the free list
            Medium,     // Collect unused blocks
            High        // Delete unused blocks
        };
        void CleanUp( Severity s );

        unsigned        MemUsed();      // for debugging

    private:
        // Assignment of Pool's is not permitted.
        Pool( Pool const & )
        {
            // empty
        }
        Pool & operator=( Pool const & )
        {
            return *this;
        }

    private:
        uint_8                  *_array;
        void                    *_pfree;
        unsigned                _blockCount;    // for debugging
        PoolIds                 _idNum;         // for debugging

        uint_8                  *_freeBlocks;

        const unsigned          _blockLen;
        const size_t            _size;
};


#endif  // _POOL_HPP