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#ifndef CYGONCE_MEMALLOC_MEMVAR_HXX

#define CYGONCE_MEMALLOC_MEMVAR_HXX

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

//

//      memvar.hxx

//

//      Memory pool with variable block class declarations

//

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

// ####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):    dsm, jlarmour

// Contributors:

// Date:         2000-06-12

// Purpose:      Define Memvar class interface

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

// Usage:        #include 

//

//

//####DESCRIPTIONEND####

//

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

// CONFIGURATION

#include 

#ifdef CYGSEM_MEMALLOC_ALLOCATOR_VARIABLE_THREADAWARE

# include 

# ifdef CYGPKG_KERNEL

#  include 

# endif

#endif

// when used as an implementation for malloc, we need the following

// to let the system know the name of the class

#define CYGCLS_MEMALLOC_MALLOC_IMPL Cyg_Mempool_Variable

// if the implementation is all that's required, don't output anything else

#ifndef __MALLOC_IMPL_WANTED

// INCLUDES

#include         // types

#include          // assertion macros

#ifdef CYGFUN_KERNEL_THREADS_TIMER

# include         // cyg_tick_count

#endif

#ifdef CYGSEM_MEMALLOC_ALLOCATOR_VARIABLE_THREADAWARE

# include   // kernel safe mempool template

#endif

#include    // implementation of a variable mem pool

#include      // Common memory allocator infra

// TYPE DEFINITIONS

class Cyg_Mempool_Variable

{

protected:

#ifdef CYGSEM_MEMALLOC_ALLOCATOR_VARIABLE_THREADAWARE

    Cyg_Mempolt2 mypool;

#else

    Cyg_Mempool_Variable_Implementation mypool;

#endif

public:

    // This API makes concrete a class which implements a thread-safe

    // kernel-savvy memory pool which manages variable size blocks.

    // 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_Variable( cyg_uint8 * /* base */, cyg_int32  /* size */,

                          cyg_int32 /* alignment */=8);

    // Destructor

    ~Cyg_Mempool_Variable();

    // get some memory; wait if none available

    // if we aren't configured to be thread-aware this is irrelevant

#ifdef CYGSEM_MEMALLOC_ALLOCATOR_VARIABLE_THREADAWARE

    cyg_uint8 *

    alloc( cyg_int32 /* size */ );

# ifdef CYGFUN_KERNEL_THREADS_TIMER

    // get some memory with a timeout

    cyg_uint8 *

    alloc( cyg_int32 /* size */, cyg_tick_count /* delay_timeout */ );

# endif

#endif

    // 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 */ =NULL );

    // 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 */ );

    CYGDBG_DEFINE_CHECK_THIS

};

#endif // ifndef __MALLOC_IMPL_WANTED

#endif // ifndef CYGONCE_MEMALLOC_MEMVAR_HXX

// EOF memvar.hxx