heap_1.c File Reference

#include <stdlib.h>
#include "FreeRTOS.h"
#include "task.h"

Go to the source code of this file.

Data Structures
union	xRTOS_HEAP
Defines
#define	MPU_WRAPPERS_INCLUDED_FROM_API_FILE
Functions
void *	pvPortMalloc (size_t xWantedSize)
void	vPortFree (void *pv)
void	vPortInitialiseBlocks (void)
size_t	xPortGetFreeHeapSize (void)
Variables
static union xRTOS_HEAP	xHeap
static size_t	xNextFreeByte = ( size_t ) 0

---

Define Documentation

#define MPU_WRAPPERS_INCLUDED_FROM_API_FILE

Definition at line 67 of file heap_1.c.

---

Function Documentation

void* pvPortMalloc

(

size_t

xWantedSize

)

Definition at line 89 of file heap_1.c.

References configTOTAL_HEAP_SIZE, portBYTE_ALIGNMENT, xRTOS_HEAP::ucHeap, vTaskSuspendAll(), xHeap, xNextFreeByte, and xTaskResumeAll().

{
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();
    
    #if( configUSE_MALLOC_FAILED_HOOK == 1 )
    {
        if( pvReturn == NULL )
        {
            extern void vApplicationMallocFailedHook( void );
            vApplicationMallocFailedHook();
        }
    }
    #endif  

    return pvReturn;
}

void vPortFree

(

void *

pv

)

Definition at line 130 of file heap_1.c.

{
    /* 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

)

Definition at line 139 of file heap_1.c.

References xNextFreeByte.

{
    /* Only required when static memory is not cleared. */
    xNextFreeByte = ( size_t ) 0;
}

size_t xPortGetFreeHeapSize

(

void

)

Definition at line 146 of file heap_1.c.

References configTOTAL_HEAP_SIZE, and xNextFreeByte.

{
    return ( configTOTAL_HEAP_SIZE - xNextFreeByte );
}

---

Variable Documentation

union xRTOS_HEAP xHeap [static]

Referenced by pvPortMalloc().

size_t xNextFreeByte = ( size_t ) 0 [static]

Definition at line 86 of file heap_1.c.

Referenced by pvPortMalloc(), vPortInitialiseBlocks(), and xPortGetFreeHeapSize().