osd-contiki/core/lib/mmem.h
2008-10-15 14:17:28 +00:00

95 lines
3.2 KiB
C
Raw Blame History

/*
* Copyright (c) 2005, Swedish Institute of Computer Science
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* This file is part of the Contiki operating system.
*
* @(#)$Id: mmem.h,v 1.2 2008/10/15 14:17:28 nvt-se Exp $
*/
/**
* \addtogroup mem
* @{
*/
/**
* \defgroup mmem Managed memory allocator
*
* The managed memory allocator is a fragmentation-free memory
* manager. It keeps the allocated memory free from fragmentation by
* compacting the memory when blocks are freed. A program that uses
* the managed memory module cannot be sure that allocated memory
* stays in place. Therefore, a level of indirection is used: access
* to allocated memory must always be done using a special macro.
*
* \note This module has not been heavily tested.
* @{
*/
/**
* \file
* Header file for the managed memory allocator
* \author
* Adam Dunkels <adam@sics.se>
*
*/
#ifndef __MMEM_H__
#define __MMEM_H__
/*---------------------------------------------------------------------------*/
/**
* \brief Get a pointer to the managed memory
* \param m A pointer to the struct mmem
* \return A pointer to the memory block, or NULL if memory could
* not be allocated.
* \author Adam Dunkels
*
* This macro is used to get a pointer to a memory block
* allocated with mmem_alloc().
*
* \hideinitializer
*/
#define MMEM_PTR(m) (struct mmem *)(m)->ptr
struct mmem {
struct mmem *next;
unsigned int size;
void *ptr;
};
/* XXX: tagga minne med "interrupt usage", vilke g<>r att man <20>r
speciellt varsam under free(). */
int mmem_alloc(struct mmem *m, unsigned int size);
void mmem_free(struct mmem *);
void mmem_init(void);
#endif /* __MMEM_H__ */
/** @} */
/** @} */