view packages/services/memalloc/common/current/include/dlmalloc.hxx @ 115:6ed91473a1cd ecos-sw-2000-08-21

Merge from eCos master repository on 2000-08-21-22:40:54-BST
author jlarmour
date Fri, 25 Aug 2000 17:32:38 +0000
parents
children e0c0827131d1
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#ifndef CYGONCE_MEMALLOC_DLMALLOC_HXX
#define CYGONCE_MEMALLOC_DLMALLOC_HXX

//==========================================================================
//
//      dlmalloc.hxx
//
//      Interface to the port of Doug Lea's malloc implementation
//
//==========================================================================
//####COPYRIGHTBEGIN####
//                                                                          
// -------------------------------------------                              
// The contents of this file are subject to the Red Hat eCos Public License 
// Version 1.1 (the "License"); you may not use this file except in         
// compliance with the License.  You may obtain a copy of the License at    
// http://www.redhat.com/                                                   
//                                                                          
// Software distributed under the License is distributed on an "AS IS"      
// basis, WITHOUT WARRANTY OF ANY KIND, either express or implied.  See the 
// License for the specific language governing rights and limitations under 
// the License.                                                             
//                                                                          
// The Original Code is eCos - Embedded Configurable Operating System,      
// released September 30, 1998.                                             
//                                                                          
// The Initial Developer of the Original Code is Red Hat.                   
// Portions created by Red Hat are                                          
// Copyright (C) 1998, 1999, 2000 Red Hat, Inc.                             
// All Rights Reserved.                                                     
// -------------------------------------------                              
//                                                                          
//####COPYRIGHTEND####
//==========================================================================
//#####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 <cyg/memalloc/dlmalloc.hxx>
//              
//
//####DESCRIPTIONEND####
//
//==========================================================================

// CONFIGURATION

#include <pkgconf/memalloc.h>

#ifdef CYGIMP_MEMALLOC_ALLOCATOR_DLMALLOC_THREADAWARE
# include <pkgconf/system.h>
# ifdef CYGPKG_KERNEL
#  include <pkgconf/kernel.h>
# 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_dlmalloc

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

// INCLUDES

#include <stddef.h>                      // size_t, ptrdiff_t
#include <cyg/infra/cyg_type.h>          // types
#ifdef CYGIMP_MEMALLOC_ALLOCATOR_DLMALLOC_THREADAWARE
# include <cyg/memalloc/mempolt2.hxx>    // kernel safe mempool template
#endif
#include <cyg/memalloc/dlmallocimpl.hxx> // dlmalloc implementation
#include <cyg/memalloc/common.hxx>       // Common memory allocator infra
#ifdef CYGFUN_KERNEL_THREADS_TIMER
# include <cyg/kernel/ktypes.h>          // cyg_tick_count
#endif


// TYPE DEFINITIONS


class Cyg_Mempool_dlmalloc
{
protected:
#ifdef CYGIMP_MEMALLOC_ALLOCATOR_DLMALLOC_THREADAWARE
    Cyg_Mempolt2<Cyg_Mempool_dlmalloc_Implementation> mypool;
#else
    Cyg_Mempool_dlmalloc_Implementation mypool;
#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( cyg_uint8 *base, cyg_int32 size, 
                          CYG_ADDRWORD argthru=0 )
        : mypool( base, size, argthru ) {}

    // Destructor
    ~Cyg_Mempool_dlmalloc() {}

    // get some memory; wait if none available
    // if we aren't configured to be thread-aware this is irrelevant
#ifdef CYGIMP_MEMALLOC_ALLOCATOR_DLMALLOC_THREADAWARE
    cyg_uint8 *
    alloc( cyg_int32 size ) { return mypool.alloc( size ); }
    
# ifdef CYGFUN_KERNEL_THREADS_TIMER
    // get some memory with a timeout
    cyg_uint8 *
    alloc( cyg_int32 size, cyg_tick_count delay_timeout ) {
        return mypool.alloc( size, delay_timeout );
    }
# endif
#endif

    // get some memory, return NULL if none available
    cyg_uint8 *
    try_alloc( cyg_int32 size ) { return mypool.try_alloc( 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 ) { 
        return mypool.resize_alloc( alloc_ptr, newsize, oldsize);
    }

    // free the memory back to the pool
    // returns true on success
    cyg_bool
    free( cyg_uint8 *ptr, cyg_int32 size=0 ) { return mypool.free(ptr, 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 ) {
        // set to 0 - if there's anything really waiting, it will be set to
        // 1 later
        status.waiting = 0;
        mypool.get_status( flags, status );
    }
};

#endif // ifndef __MALLOC_IMPL_WANTED

#endif // ifndef CYGONCE_MEMALLOC_DLMALLOC_HXX
// EOF dlmalloc.hxx