/* | |
FreeRTOS.org V5.1.2 - Copyright (C) 2003-2009 Richard Barry. | |
This file is part of the FreeRTOS.org distribution. | |
FreeRTOS.org 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 of the License, or | |
(at your option) any later version. | |
FreeRTOS.org 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 FreeRTOS.org; if not, write to the Free Software | |
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
A special exception to the GPL can be applied should you wish to distribute | |
a combined work that includes FreeRTOS.org, without being obliged to provide | |
the source code for any proprietary components. See the licensing section | |
of http://www.FreeRTOS.org for full details of how and when the exception | |
can be applied. | |
*************************************************************************** | |
*************************************************************************** | |
* * | |
* Get the FreeRTOS eBook! See http://www.FreeRTOS.org/Documentation * | |
* * | |
* This is a concise, step by step, 'hands on' guide that describes both * | |
* general multitasking concepts and FreeRTOS specifics. It presents and * | |
* explains numerous examples that are written using the FreeRTOS API. * | |
* Full source code for all the examples is provided in an accompanying * | |
* .zip file. * | |
* * | |
*************************************************************************** | |
*************************************************************************** | |
Please ensure to read the configuration and relevant port sections of the | |
online documentation. | |
http://www.FreeRTOS.org - Documentation, latest information, license and | |
contact details. | |
http://www.SafeRTOS.com - A version that is certified for use in safety | |
critical systems. | |
http://www.OpenRTOS.com - Commercial support, development, porting, | |
licensing and training services. | |
*/ | |
/* | |
Changes between V2.5.1 and V2.5.1 | |
+ The memory pool has been defined within a struct to ensure correct memory | |
alignment on 32bit systems. | |
Changes between V2.6.1 and V3.0.0 | |
+ An overflow check has been added to ensure the next free byte variable | |
does not wrap around. | |
*/ | |
/* | |
* The simplest possible implementation of pvPortMalloc(). Note that this | |
* implementation does NOT allow allocated memory to be freed again. | |
* | |
* See heap_2.c and heap_3.c for alternative implementations, and the memory | |
* management pages of http://www.FreeRTOS.org for more information. | |
*/ | |
#include <stdlib.h> | |
#include "FreeRTOS.h" | |
#include "task.h" | |
/* Setup the correct byte alignment mask for the defined byte alignment. */ | |
#if portBYTE_ALIGNMENT == 8 | |
#define heapBYTE_ALIGNMENT_MASK ( ( size_t ) 0x0007 ) | |
#endif | |
#if portBYTE_ALIGNMENT == 4 | |
#define heapBYTE_ALIGNMENT_MASK ( ( size_t ) 0x0003 ) | |
#endif | |
#if portBYTE_ALIGNMENT == 2 | |
#define heapBYTE_ALIGNMENT_MASK ( ( size_t ) 0x0001 ) | |
#endif | |
#if portBYTE_ALIGNMENT == 1 | |
#define heapBYTE_ALIGNMENT_MASK ( ( size_t ) 0x0000 ) | |
#endif | |
#ifndef heapBYTE_ALIGNMENT_MASK | |
#error "Invalid portBYTE_ALIGNMENT definition" | |
#endif | |
/* Allocate the memory for the heap. The struct is used to force byte | |
alignment without using any non-portable code. */ | |
static struct xRTOS_HEAP | |
{ | |
unsigned portLONG ulDummy; | |
unsigned portCHAR ucHeap[ configTOTAL_HEAP_SIZE ]; | |
} xHeap; | |
static size_t xNextFreeByte = ( size_t ) 0; | |
/*-----------------------------------------------------------*/ | |
void *pvPortMalloc( size_t xWantedSize ) | |
{ | |
void *pvReturn = NULL; | |
/* Ensure that blocks are always aligned to the required number of bytes. */ | |
#if portBYTE_ALIGNMENT != 1 | |
if( xWantedSize & heapBYTE_ALIGNMENT_MASK ) | |
{ | |
/* Byte alignment required. */ | |
xWantedSize += ( portBYTE_ALIGNMENT - ( xWantedSize & heapBYTE_ALIGNMENT_MASK ) ); | |
} | |
#endif | |
vTaskSuspendAll(); | |
{ | |
/* Check there is enough room left for the allocation. */ | |
if( ( ( xNextFreeByte + xWantedSize ) < configTOTAL_HEAP_SIZE ) && | |
( ( xNextFreeByte + xWantedSize ) > xNextFreeByte ) )/* Check for overflow. */ | |
{ | |
/* Return the next free byte then increment the index past this | |
block. */ | |
pvReturn = &( xHeap.ucHeap[ xNextFreeByte ] ); | |
xNextFreeByte += xWantedSize; | |
} | |
} | |
xTaskResumeAll(); | |
return pvReturn; | |
} | |
/*-----------------------------------------------------------*/ | |
void vPortFree( void *pv ) | |
{ | |
/* Memory cannot be freed using this scheme. See heap_2.c and heap_3.c | |
for alternative implementations, and the memory management pages of | |
http://www.FreeRTOS.org for more information. */ | |
( void ) pv; | |
} | |
/*-----------------------------------------------------------*/ | |
void vPortInitialiseBlocks( void ) | |
{ | |
/* Only required when static memory is not cleared. */ | |
xNextFreeByte = ( size_t ) 0; | |
} | |