Espressif ESP32-S2 User Manual

Chapter 2. API Reference
Functions
esp_err_t heap_caps_register_failed_alloc_callback(esp_alloc_failed_hook_t callback)
registers a callback function to be invoked if a memory allocation operation fails
Return ESP_OK if callback was registered.
Parameters
• callback: caller defined callback to be invoked
void *heap_caps_malloc(size_t size, uint32_t caps)
Allocate a chunk of memory which has the given capabilities.
Equivalent semantics to libc malloc(), for capability-aware memory.
In IDF, malloc(p) is equivalent to heap_caps_malloc(p, MALLOC_CAP_8BIT).
Return A pointer to the memory allocated on success, NULL on failure
Parameters
• size: Size, in bytes, of the amount of memory to allocate
• caps: Bitwise OR of MALLOC_CAP_* flags indicating the type of memory to be returned
void heap_caps_free(void *ptr)
Free memory previously allocated via heap_caps_malloc() or heap_caps_realloc().
Equivalent semantics to libc free(), for capability-aware memory.
In IDF, free(p) is equivalent to heap_caps_free(p).
Parameters
• ptr: Pointer to memory previously returned from heap_caps_malloc() or heap_caps_realloc(). Can
be NULL.
void *heap_caps_realloc(void *ptr, size_t size, uint32_t caps)
Reallocate memory previously allocated via heap_caps_malloc() or heap_caps_realloc().
Equivalent semantics to libc realloc(), for capability-aware memory.
In IDF, realloc(p, s) is equivalent to heap_caps_realloc(p, s, MALLOC_CAP_8BIT).
‘caps’parameter can be different to the capabilities that any original ‘ptr’was allocated with. In this way,
realloc can be used to “move”a buffer if necessary to ensure it meets a new set of capabilities.
Return Pointer to a new buffer of size ‘size’with capabilities ‘caps’, or NULL if allocation failed.
Parameters
• ptr: Pointer to previously allocated memory, or NULL for a new allocation.
• size: Size of the new buffer requested, or 0 to free the buffer.
• caps: Bitwise OR of MALLOC_CAP_* flags indicating the type of memory desired for the new
allocation.
void *heap_caps_aligned_alloc(size_t alignment, size_t size, uint32_t caps)
Allocate a aligned chunk of memory which has the given capabilities.
Equivalent semantics to libc aligned_alloc(), for capability-aware memory.
Return A pointer to the memory allocated on success, NULL on failure
Parameters
• alignment: How the pointer received needs to be aligned must be a power of two
• size: Size, in bytes, of the amount of memory to allocate
• caps: Bitwise OR of MALLOC_CAP_* flags indicating the type of memory to be returned
void heap_caps_aligned_free(void *ptr)
Used to deallocate memory previously allocated with heap_caps_aligned_alloc.
Note This function is deprecated, plase consider using heap_caps_free() instead
Parameters
• ptr: Pointer to the memory allocated
void *heap_caps_aligned_calloc(size_t alignment, size_t n, size_t size, uint32_t caps)
Allocate a aligned chunk of memory which has the given capabilities. The initialized value in the memory is
set to zero.
Espressif Systems 974
Submit Document Feedback
Release v4.4

Espressif ESP32-S2 Specifications

General

Brand	Espressif
Model	ESP32-S2
Category	Single board computers
Language	English