Memory Manager

Memory Manager for the nRFXX SDK. More...

Functions
uint32_t	nrf_mem_init (void)
	Initializes Memory Manager. More...
uint32_t	nrf_mem_reserve (uint8_t **pp_buffer, uint32_t *p_size)
	Reserves a block of memory for the application. More...
void *	nrf_malloc (uint32_t size)
	'malloc' styled memory allocation function. More...
void *	nrf_calloc (uint32_t nmemb, uint32_t size)
	'calloc' styled memory allocation function. More...
void	nrf_free (void *p_buffer)
	Free allocated memory - standard 'free' styles API. More...
void *	nrf_realloc (void *p_buffer, uint32_t size)
	Memory reallocation (trim) function. More...

Detailed Description

Memory Manager for the nRFXX SDK.

This module allows for dynamic use of memory. Currently, this module can be used only to allocate and free memory in the RAM.

The Memory Manager manages static memory blocks of fixed sizes. These blocks can be requested for usage, and freed when the application no longer needs them. A maximum of seven block categories can be managed by the module. These block categories are identified by xxsmall, xmall, small, medium, large, xlarge, and xxlarge. They are ordered in increasing block sizes. The size and the count of each of the block categories can be configured based on the application requirements in the configuration file sdk_config.h. To use fewer than seven buffer pools, do not define the count for the unwanted block or explicitly set it to zero. At least one block category must be configured for this module to function as expected.

Function Documentation

void* nrf_calloc	(	uint32_t	nmemb,
		uint32_t	size
	)

'calloc' styled memory allocation function.

API to allocate zero-initialized memory of size count*size.

Parameters

[in]	nmemb	Number of elements of 'size' bytes.
[in]	size	Size of each element allocated.

Return values

Valid,zero-initialized

memory location if the procedure was successful, else, NULL.

void nrf_free

(

void *

p_buffer

)

Free allocated memory - standard 'free' styles API.

API to resubmit memory allocated, same in functionality nrf_free.

Parameters

[out]

p_buffer

Pointer to the memory block that is being freed.

void* nrf_malloc

(

uint32_t

size

)

'malloc' styled memory allocation function.

API to allocate memory, same as nrf_mem_reserve but uses malloc signature.

Parameters

[in]

size

Requested memory size.

Return values

Valid

memory location if the procedure was successful, else, NULL.

uint32_t nrf_mem_init

(

void

)

Initializes Memory Manager.

API to initialize the Memory Manager. Always call this API before using any of the other APIs of the module. This API should be called only once.

Return values

NRF_SUCCESS

If initialization was successful. Otherwise, an error code that indicates the reason for the failure is returned.

Warning

If this API fails, the application shall not proceed with using other APIs of this module.

uint32_t nrf_mem_reserve	(	uint8_t **	pp_buffer,
		uint32_t *	p_size
	)

Reserves a block of memory for the application.

API to request a contiguous memory block of the given length. If the memory allocation succeeds, pp_buffer points to the memory block. If the memory allocation fails, pp_buffer points to NULL and the return value of the API indicates the reason for the failure. The memory block reserved using this API can be freed using the nrf_free function.

Parameters

[out]	pp_buffer	Pointer to the allocated memory block if memory allocation succeeds; otherwise points to NULL.
[in,out]	p_size	Requested memory size. This parameter returns the actual size allocated. If the procedure was successful, the actual size returned is always greater than or equal to requested size, never less.

Return values

NRF_SUCCESS	If memory was successfully allocated. Otherwise, an error code indicating the reason for failure.
NRF_ERROR_INVALID_PARAM	If the requested memory size is zero or greater than the largest memory block that the module is configured to support.
NRF_ERROR_NO_MEM	If there is no memory available of the requested size.

void* nrf_realloc	(	void *	p_buffer,
		uint32_t	size
	)

Memory reallocation (trim) function.

API to reallocate memory or to trim it. Trim is mentioned here to avoid use of API to request memory size larger than original memory allocated.

Parameters

[in]	p_buffer	Pointer to the memory block that needs to be trimmed.
[in]	size	Size of memory at the beginning of the buffer to be left untrimmed.

Return values

Pointer

to memory location with trimmed size, else, NULL.