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#ifndef CYGONCE_MEMALLOC_MVARIMPL_HXX

#define CYGONCE_MEMALLOC_MVARIMPL_HXX

//==========================================================================

//

//      mvarimpl.hxx

//

//      Memory pool with variable block class declarations

//

//==========================================================================

// ####ECOSGPLCOPYRIGHTBEGIN####

// -------------------------------------------

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// Copyright (C) 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc.

//

// eCos is free software; you can redistribute it and/or modify it under

// the terms of the GNU General Public License as published by the Free

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// version.

//

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// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

// for more details.

//

// You should have received a copy of the GNU General Public License

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// 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

//

// As a special exception, if other files instantiate templates or use

// macros or inline functions from this file, or you compile this file

// and link it with other works to produce a work based on this file,

// this file does not by itself cause the resulting work to be covered by

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// must still be made available in accordance with section (3) of the GNU

// General Public License v2.

//

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// on this file might be covered by the GNU General Public License.

// -------------------------------------------

// ####ECOSGPLCOPYRIGHTEND####

//==========================================================================

//#####DESCRIPTIONBEGIN####

//

// Author(s):    dsm, jlarmour

// Contributors:

// Date:         2000-06-12

// Purpose:      Define Mvarimpl class interface

// Description:  Inline class for constructing a variable block allocator

// Usage:        #include 

//

//

//####DESCRIPTIONEND####

//

//==========================================================================

#include 

#include 

#include      // Common memory allocator infra

class Cyg_Mempool_Variable_Implementation {

protected:

    // these constructors are explicitly disallowed

    Cyg_Mempool_Variable_Implementation() {};

//    Cyg_Mempool_Variable_Implementation( Cyg_Mempool_Variable_Implementation &ref )

//    {};

    Cyg_Mempool_Variable_Implementation &

    operator=( Cyg_Mempool_Variable_Implementation &ref )

    { return ref; };

    struct memdq {

        struct memdq *prev, *next;

        cyg_int32 size;

    };

    struct memdq head;

    cyg_uint8  *obase;

    cyg_int32  osize;

    cyg_uint8  *bottom;

    cyg_uint8  *top;

    cyg_int32  alignment;

    cyg_int32  freemem;

    // round up size passed to alloc/free to a size that will be used

    // for allocation

    cyg_int32

    roundup(cyg_int32 size);

    struct memdq *

    addr2memdq( cyg_uint8 *addr );

    struct memdq *

    alloc2memdq( cyg_uint8 *addr );

    cyg_uint8 *

    memdq2alloc( struct memdq *dq );

    void

    insert_free_block( struct memdq *freedq );

public:

    // THIS is the public API of memory pools generally that can have the

    // kernel oriented thread-safe package layer atop.

    // Constructor: gives the base and size of the arena in which memory is

    // to be carved out.

    Cyg_Mempool_Variable_Implementation(

        cyg_uint8 *  /* base */,

        cyg_int32    /* size */,

        CYG_ADDRWORD /* alignment */ = 8 );

    // Destructor

    ~Cyg_Mempool_Variable_Implementation();

    // get size bytes of memory

    cyg_uint8 *

    try_alloc( cyg_int32 /* size */ );

    // resize existing allocation, if oldsize is non-NULL, previous

    // allocation size is placed into it. If previous size not available,

    // it is set to 0. NB previous allocation size may have been rounded up.

    // Occasionally the allocation can be adjusted *backwards* as well as,

    // or instead of forwards, therefore the address of the resized

    // allocation is returned, or NULL if no resizing was possible.

    // Note that this differs from ::realloc() in that no attempt is

    // made to call malloc() if resizing is not possible - that is left

    // to higher layers. The data is copied from old to new though.

    // The effects of alloc_ptr==NULL or newsize==0 are undefined

    cyg_uint8 *

    resize_alloc( cyg_uint8 *alloc_ptr, cyg_int32 newsize,

                  cyg_int32 *oldsize );

    // free size bytes of memory back to the pool

    // returns true on success

    cyg_bool

    free( cyg_uint8 * /* ptr */,

          cyg_int32   /* size */ );

    // Get memory pool status

    // flags is a bitmask of requested fields to fill in. The flags are

    // defined in common.hxx

    void

    get_status( cyg_mempool_status_flag_t /* flags */,

                Cyg_Mempool_Status & /* status */ );

};

#include 

// -------------------------------------------------------------------------

#endif // ifndef CYGONCE_MEMALLOC_MVARIMPL_HXX

// EOF mvarimpl.hxx