/****************************************************************************

 *  This file is part of PPMd project                                       *

 *  Written and distributed to public domain by Dmitry Shkarin 1997,        *

 *  1999-2000                                                               *

 *  Contents: interface to memory allocation routines                       *

 ****************************************************************************/

#if !defined(_SUBALLOC_H_)

#define _SUBALLOC_H_

#if defined(__GNUC__) && defined(ALLOW_MISALIGNED)

#define RARPPM_PACK_ATTR __attribute__ ((packed))

#else

#define RARPPM_PACK_ATTR

#endif /* defined(__GNUC__) */

#ifdef ALLOW_MISALIGNED

#pragma pack(1)

#endif

struct RARPPM_MEM_BLK 

{

  ushort Stamp, NU;

  RARPPM_MEM_BLK* next, * prev;

  void insertAt(RARPPM_MEM_BLK* p) 

  {

    next=(prev=p)->next;

    p->next=next->prev=this;

  }

  void remove() 

  {

    prev->next=next;

    next->prev=prev;

  }

} RARPPM_PACK_ATTR;

#ifdef ALLOW_MISALIGNED

#ifdef _AIX

#pragma pack(pop)

#else

#pragma pack()

#endif

#endif

class SubAllocator

{

  private:

    static const int N1=4, N2=4, N3=4, N4=(128+3-1*N1-2*N2-3*N3)/4;

    static const int N_INDEXES=N1+N2+N3+N4;

    struct RAR_NODE

    {

      RAR_NODE* next;

    };

    inline void InsertNode(void* p,int indx);

    inline void* RemoveNode(int indx);

    inline uint U2B(int NU);

    inline void SplitBlock(void* pv,int OldIndx,int NewIndx);

    inline void GlueFreeBlocks();

    void* AllocUnitsRare(int indx);

    inline RARPPM_MEM_BLK* MBPtr(RARPPM_MEM_BLK *BasePtr,int Items);

    long SubAllocatorSize;

    byte Indx2Units[N_INDEXES], Units2Indx[128], GlueCount;

    byte *HeapStart,*LoUnit, *HiUnit;

    struct RAR_NODE FreeList[N_INDEXES];

  public:

    SubAllocator();

    ~SubAllocator() {StopSubAllocator();}

    void Clean();

    bool StartSubAllocator(int SASize);

    void StopSubAllocator();

    void  InitSubAllocator();

    inline void* AllocContext();

    inline void* AllocUnits(int NU);

    inline void* ExpandUnits(void* ptr,int OldNU);

    inline void* ShrinkUnits(void* ptr,int OldNU,int NewNU);

    inline void  FreeUnits(void* ptr,int OldNU);

    long GetAllocatedMemory() {return(SubAllocatorSize);}

    byte *pText, *UnitsStart,*HeapEnd,*FakeUnitsStart;

};

#endif /* !defined(_SUBALLOC_H_) */