CMSIS FreeRTOS dynamic allocation - embedded

Question

I'm working on an embedded system that has CMSIS FreeRtos with heap4 as memory management scheme.
Now I'm trying to port the mbedTls to my system and I must provide dynamic allocation functions like alloc and free.
mbedTLS require two function to allocate and free memory.
These are the function prototypes required by mbedTLS:
void * (*mbedtls_calloc)( size_t, size_t ) = MBEDTLS_PLATFORM_STD_CALLOC;
void (*mbedtls_free)( void * ) = MBEDTLS_PLATFORM_STD_FREE;
int mbedtls_platform_set_calloc_free( void * (*calloc_func)( size_t, size_t ),
void (*free_func)( void * ) )
Which is the best way to use correctly the heap provided by FreeRTOS?
Memory pool for example.
Heap4 does not provide function like calloc and free. So, which function should I wrap to allow mbedTls to allocate memory?
Thanks in advance for the help.
Federico

Answer 1

STEP 1:
Make a wrapper of calloc and free functions in your source as shown below.
void *pvWrap_mbedtls_calloc( size_t sNb, size_t sSize )
{
void *vPtr = NULL;
if (sSize > 0) {
vPtr = pvPortMalloc(sSize * sNb); // Call FreeRTOS or other standard API
if(vPtr)
memset(vPtr, 0, (sSize * sNb)); // Must required
}
return vPtr;
}
void vWrap_mbedtls_free( void *vPtr )
{
if (vPtr) {
vPortFree(vPtr); // Call FreeRTOS or other standard API
}
}
STEP 2: Register these API at initialization time of you application as shown below.
void Custom_MBEDTLS_Init(void)
{
mbedtls_platform_set_calloc_free(&pvWrap_mbedtls_calloc, &vWrap_mbedtls_free);
}