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[/] [openrisc/] [trunk/] [rtos/] [freertos-6.1.1/] [Demo/] [CORTEX_LM3S811_KEIL/] [heap/] [heap_1.c] - Blame information for rev 581

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1 581 jeremybenn
/*
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    FreeRTOS V6.1.1 - Copyright (C) 2011 Real Time Engineers Ltd.
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    ***************************************************************************
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    *                                                                         *
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    * If you are:                                                             *
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    *                                                                         *
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    *    + New to FreeRTOS,                                                   *
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    *    + Wanting to learn FreeRTOS or multitasking in general quickly       *
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    *    + Looking for basic training,                                        *
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    *    + Wanting to improve your FreeRTOS skills and productivity           *
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    *                                                                         *
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    * then take a look at the FreeRTOS books - available as PDF or paperback  *
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    *                                                                         *
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    *        "Using the FreeRTOS Real Time Kernel - a Practical Guide"        *
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    *                  http://www.FreeRTOS.org/Documentation                  *
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    *                                                                         *
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    * A pdf reference manual is also available.  Both are usually delivered   *
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    * to your inbox within 20 minutes to two hours when purchased between 8am *
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    * and 8pm GMT (although please allow up to 24 hours in case of            *
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    * exceptional circumstances).  Thank you for your support!                *
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    *                                                                         *
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    ***************************************************************************
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    This file is part of the FreeRTOS distribution.
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    FreeRTOS is free software; you can redistribute it and/or modify it under
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    the terms of the GNU General Public License (version 2) as published by the
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    Free Software Foundation AND MODIFIED BY the FreeRTOS exception.
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    ***NOTE*** The exception to the GPL is included to allow you to distribute
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    a combined work that includes FreeRTOS without being obliged to provide the
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    source code for proprietary components outside of the FreeRTOS kernel.
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    FreeRTOS is distributed in the hope that it will be useful, but WITHOUT
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    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
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    more details. You should have received a copy of the GNU General Public
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    License and the FreeRTOS license exception along with FreeRTOS; if not it
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    can be viewed here: http://www.freertos.org/a00114.html and also obtained
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    by writing to Richard Barry, contact details for whom are available on the
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    FreeRTOS WEB site.
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    1 tab == 4 spaces!
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    http://www.FreeRTOS.org - Documentation, latest information, license and
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    contact details.
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    http://www.SafeRTOS.com - A version that is certified for use in safety
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    critical systems.
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    http://www.OpenRTOS.com - Commercial support, development, porting,
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    licensing and training services.
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*/
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/*
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 * The simplest possible implementation of pvPortMalloc().  Note that this
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 * implementation does NOT allow allocated memory to be freed again.
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 *
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 * See heap_2.c and heap_3.c for alternative implementations, and the memory
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 * management pages of http://www.FreeRTOS.org for more information.
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 */
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#include <stdlib.h>
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#include "FreeRTOS.h"
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#include "task.h"
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/* Setup the correct byte alignment mask for the defined byte alignment. */
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#if portBYTE_ALIGNMENT == 4
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        #define heapBYTE_ALIGNMENT_MASK ( ( size_t ) 0x0003 )
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#endif
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#if portBYTE_ALIGNMENT == 2
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        #define heapBYTE_ALIGNMENT_MASK ( ( size_t ) 0x0001 )
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#endif
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#if portBYTE_ALIGNMENT == 1 
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        #define heapBYTE_ALIGNMENT_MASK ( ( size_t ) 0x0000 )
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#endif
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#ifndef heapBYTE_ALIGNMENT_MASK
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        #error "Invalid portBYTE_ALIGNMENT definition"
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#endif
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/* Allocate the memory for the heap.  The struct is used to force byte
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alignment without using any non-portable code. */
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extern struct xRTOS_HEAP
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{
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        unsigned long ulDummy;
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        unsigned char ucHeap[ configTOTAL_HEAP_SIZE ];
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} xHeap;
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static size_t xNextFreeByte = ( size_t ) 0;
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/*-----------------------------------------------------------*/
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void *pvPortMalloc( size_t xWantedSize )
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{
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void *pvReturn = NULL;
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        /* Ensure that blocks are always aligned to the required number of bytes. */
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        #if portBYTE_ALIGNMENT != 1
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                if( xWantedSize & heapBYTE_ALIGNMENT_MASK )
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                {
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                        /* Byte alignment required. */
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                        xWantedSize += ( portBYTE_ALIGNMENT - ( xWantedSize & heapBYTE_ALIGNMENT_MASK ) );
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                }
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        #endif
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        vTaskSuspendAll();
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        {
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                /* Check there is enough room left for the allocation. */
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                if( ( ( xNextFreeByte + xWantedSize ) < configTOTAL_HEAP_SIZE ) &&
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                        ( ( xNextFreeByte + xWantedSize ) > xNextFreeByte )     )/* Check for overflow. */
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                {
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                        /* Return the next free byte then increment the index past this
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                        block. */
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                        pvReturn = &( xHeap.ucHeap[ xNextFreeByte ] );
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                        xNextFreeByte += xWantedSize;
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                }
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        }
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        xTaskResumeAll();
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        return pvReturn;
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}
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/*-----------------------------------------------------------*/
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void vPortFree( void *pv )
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{
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        /* Memory cannot be freed using this scheme.  See heap_2.c and heap_3.c
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        for alternative implementations, and the memory management pages of
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        http://www.FreeRTOS.org for more information. */
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        ( void ) pv;
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}
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/*-----------------------------------------------------------*/
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void vPortInitialiseBlocks( void )
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{
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        /* Only required when static memory is not cleared. */
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        xNextFreeByte = ( size_t ) 0;
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}
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