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/*
* FreeRTOS V202104.00
* Copyright (C) 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of
* this software and associated documentation files (the "Software"), to deal in
* the Software without restriction, including without limitation the rights to
* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
* the Software, and to permit persons to whom the Software is furnished to do so,
* subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
* FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
* COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
* IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
* http://www.FreeRTOS.org
* http://aws.amazon.com/freertos
*
* 1 tab == 4 spaces!
*/
/*
* 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"
/* Allocate the memory for the heap. The struct is used to force byte
alignment without using any non-portable code. */
extern struct xRTOS_HEAP
{
unsigned long ulDummy;
unsigned char 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 & portBYTE_ALIGNMENT_MASK )
{
/* Byte alignment required. */
xWantedSize += ( portBYTE_ALIGNMENT - ( xWantedSize & portBYTE_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;
}
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