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#ifndef CYGONCE_MEMALLOC_DLMALLOCIMPL_HXX

#define CYGONCE_MEMALLOC_DLMALLOCIMPL_HXX

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

//

//      dlmallocimpl.hxx

//

//      Interface to the port of Doug Lea's malloc implementation

//

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

// ####ECOSGPLCOPYRIGHTBEGIN####

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

// This file is part of eCos, the Embedded Configurable Operating System.

// 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

// Software Foundation; either version 2 or (at your option) any later

// version.

//

// eCos is distributed in the hope that it will be useful, but WITHOUT

// 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

// along with eCos; if not, write to the Free Software Foundation, Inc.,

// 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

// the GNU General Public License. However the source code for this file

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

// General Public License v2.

//

// This exception does not invalidate any other reasons why a work based

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

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

// ####ECOSGPLCOPYRIGHTEND####

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

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

//

// Author(s):    jlarmour

// Contributors:

// Date:         2000-06-18

// Purpose:      Define standard interface to Doug Lea's malloc implementation

// Description:  Doug Lea's malloc has been ported to eCos. This file provides

//               the interface between the implementation and the standard

//               memory allocator interface required by eCos

// Usage:        #include 

//

//

//####DESCRIPTIONEND####

//

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

// CONFIGURATION

#include 

// INCLUDES

#include                     // size_t, ptrdiff_t

#include         // types

#include      // Common memory allocator infra

// As a special case, override CYGIMP_MEMALLOC_ALLOCATOR_DLMALLOC_SAFE_MULTIPLE

// if the malloc config says so

#ifdef CYGIMP_MEMALLOC_MALLOC_DLMALLOC

// forward declaration to prevent header dependency problems

class Cyg_Mempool_dlmalloc;

# include 

# if (CYGMEM_HEAP_COUNT > 1) && \

     !defined(CYGIMP_MEMALLOC_ALLOCATOR_DLMALLOC_SAFE_MULTIPLE)

#  define CYGIMP_MEMALLOC_ALLOCATOR_DLMALLOC_SAFE_MULTIPLE 1

# endif

#endif

// CONSTANTS

// number of bins - but changing this alone will not change the number of

// bins!

#define CYGPRI_MEMALLOC_ALLOCATOR_DLMALLOC_NAV 128

// TYPE DEFINITIONS

class Cyg_Mempool_dlmalloc_Implementation

{

public:

    /* cyg_dlmalloc_size_t is the word-size used for internal bookkeeping

       of chunk sizes. On a 64-bit machine, you can reduce malloc

       overhead, especially for very small chunks, by defining

       cyg_dlmalloc_size_t to be a 32-bit type at the expense of not

       being able to handle requests greater than 2^31. This limitation is

       hardly ever a concern; you are encouraged to set this. However, the

       default version is the same as size_t. */

    typedef size_t Cyg_dlmalloc_size_t;

    struct malloc_chunk

    {

        Cyg_dlmalloc_size_t prev_size; /* Size of previous chunk (if free). */

        Cyg_dlmalloc_size_t size;      /* Size in bytes, including overhead. */

        struct malloc_chunk* fd;   /* double links -- used only if free. */

        struct malloc_chunk* bk;

    };

protected:

    /* The first value returned from sbrk */

    cyg_uint8 *arenabase;

    /* The total memory in the pool */

    cyg_int32 arenasize;

#ifdef CYGIMP_MEMALLOC_ALLOCATOR_DLMALLOC_SAFE_MULTIPLE

    struct Cyg_Mempool_dlmalloc_Implementation::malloc_chunk *

    av_[ CYGPRI_MEMALLOC_ALLOCATOR_DLMALLOC_NAV * 2 + 2 ];

#endif

#ifdef CYGDBG_MEMALLOC_ALLOCATOR_DLMALLOC_DEBUG

    void

    do_check_chunk( struct malloc_chunk * );

    void

    do_check_free_chunk( struct malloc_chunk * );

    void

    do_check_inuse_chunk( struct malloc_chunk * );

    void

    do_check_malloced_chunk( struct malloc_chunk *, Cyg_dlmalloc_size_t );

#endif

public:

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

    // to be carved out, note that management structures are taken from the

    // same arena.

    Cyg_Mempool_dlmalloc_Implementation( cyg_uint8 *  /* base */,

                                         cyg_int32    /* size */,

                                         CYG_ADDRWORD /* argthru */ );

    // Destructor

    ~Cyg_Mempool_dlmalloc_Implementation() {}

    // get some memory, return NULL if none available

    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 the memory back to the pool

    // returns true on success

    cyg_bool

    free( cyg_uint8 * /* ptr */, cyg_int32 /* size */ =0 );

    // 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 */ );

};

#endif // ifndef CYGONCE_MEMALLOC_DLMALLOCIMPL_HXX

// EOF dlmallocimpl.hxx