# lv_mem.h (/api/stdlib/lv_mem_h) Functions [#functions] lv_mem_init [#lv_mem_init] Initialize to use malloc/free/realloc etc ```c title=" " lineNumbers=1 void lv_mem_init(void) ``` lv_mem_deinit [#lv_mem_deinit] Drop all dynamically allocated memory and reset the memory pools' state ```c title=" " lineNumbers=1 void lv_mem_deinit(void) ``` lv_mem_add_pool [#lv_mem_add_pool] ```c title=" " lineNumbers=1 lv_mem_pool_t lv_mem_add_pool(void *mem, size_t bytes) ``` Parameters | Name | Type | | ------- | ------------------------- | | `mem` | `void *` | | `bytes` | | lv_mem_remove_pool [#lv_mem_remove_pool] ```c title=" " lineNumbers=1 void lv_mem_remove_pool(lv_mem_pool_t pool) ``` Parameters | Name | Type | | ------ | -------------------------------- | | `pool` | | lv_malloc [#lv_malloc] Allocate memory dynamically ```c title=" " lineNumbers=1 void * lv_malloc(size_t size) ``` Parameters | Name | Type | Description | | ------ | ------------------------- | ----------------------- | | `size` | | requested size in bytes | **Returns:** `void *` — pointer to allocated uninitialized memory, or NULL on failure lv_calloc [#lv_calloc] Allocate a block of zeroed memory dynamically ```c title=" " lineNumbers=1 void * lv_calloc(size_t num, size_t size) ``` Parameters | Name | Type | Description | | ------ | ------------------------- | -------------------------------------------- | | `num` | | requested number of element to be allocated. | | `size` | | requested size of each element in bytes. | **Returns:** `void *` — pointer to allocated zeroed memory, or NULL on failure lv_zalloc [#lv_zalloc] Allocate zeroed memory dynamically ```c title=" " lineNumbers=1 void * lv_zalloc(size_t size) ``` Parameters | Name | Type | Description | | ------ | ------------------------- | ----------------------- | | `size` | | requested size in bytes | **Returns:** `void *` — pointer to allocated zeroed memory, or NULL on failure lv_malloc_zeroed [#lv_malloc_zeroed] Allocate zeroed memory dynamically ```c title=" " lineNumbers=1 void * lv_malloc_zeroed(size_t size) ``` Parameters | Name | Type | Description | | ------ | ------------------------- | ----------------------- | | `size` | | requested size in bytes | **Returns:** `void *` — pointer to allocated zeroed memory, or NULL on failure lv_free [#lv_free] Free an allocated data ```c title=" " lineNumbers=1 void lv_free(void *data) ``` Parameters | Name | Type | Description | | ------ | -------- | ------------------------------ | | `data` | `void *` | pointer to an allocated memory | lv_realloc [#lv_realloc] Reallocate a memory with a new size. The old content will be kept. ```c title=" " lineNumbers=1 void * lv_realloc(void *data_p, size_t new_size) ``` Parameters | Name | Type | Description | | ---------- | ------------------------- | -------------------------------------------------------------------------------------------- | | `data_p` | `void *` | pointer to an allocated memory. Its content will be copied to the new memory block and freed | | `new_size` | | the desired new size in byte | **Returns:** `void *` — pointer to the new memory, NULL on failure lv_reallocf [#lv_reallocf] Reallocate a memory with a new size. The old content will be kept. In case of failure, the old pointer is free'd. ```c title=" " lineNumbers=1 void * lv_reallocf(void *data_p, size_t new_size) ``` Parameters | Name | Type | Description | | ---------- | ------------------------- | -------------------------------------------------------------------------------------------- | | `data_p` | `void *` | pointer to an allocated memory. Its content will be copied to the new memory block and freed | | `new_size` | | the desired new size in byte | **Returns:** `void *` — pointer to the new memory, NULL on failure lv_malloc_core [#lv_malloc_core] Used internally to execute a plain `malloc` operation ```c title=" " lineNumbers=1 void * lv_malloc_core(size_t size) ``` Parameters | Name | Type | Description | | ------ | ------------------------- | ------------------------- | | `size` | | size in bytes to `malloc` | lv_free_core [#lv_free_core] Used internally to execute a plain `free` operation ```c title=" " lineNumbers=1 void lv_free_core(void *p) ``` Parameters | Name | Type | Description | | ---- | -------- | ---------------------- | | `p` | `void *` | memory address to free | lv_realloc_core [#lv_realloc_core] Used internally to execute a plain realloc operation ```c title=" " lineNumbers=1 void * lv_realloc_core(void *p, size_t new_size) ``` Parameters | Name | Type | Description | | ---------- | ------------------------- | ------------------------- | | `p` | `void *` | memory address to realloc | | `new_size` | | size in bytes to realloc | lv_mem_monitor_core [#lv_mem_monitor_core] Used internally by to gather LVGL heap state information. ```c title=" " lineNumbers=1 void lv_mem_monitor_core(lv_mem_monitor_t *mon_p) ``` Parameters | Name | Type | Description | | ------- | ---------------------------------------------------------------- | ---------------------------------------------------------------------- | | `mon_p` | | pointer to object to be populated. | lv_mem_test_core [#lv_mem_test_core] ```c title=" " lineNumbers=1 lv_result_t lv_mem_test_core(void) ``` lv_mem_test [#lv_mem_test] Tests the memory allocation system by allocating and freeing a block of memory. ```c title=" " lineNumbers=1 lv_result_t lv_mem_test(void) ``` **Returns:** — LV\_RESULT\_OK if the memory allocation system is working properly, or LV\_RESULT\_INVALID if there is an error. lv_mem_monitor [#lv_mem_monitor] Give information about the work memory of dynamic allocation ```c title=" " lineNumbers=1 void lv_mem_monitor(lv_mem_monitor_t *mon_p) ``` Parameters | Name | Type | Description | | ------- | ---------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------- | | `mon_p` | | pointer to a variable, the result of the analysis will be stored here | Structs [#structs] lv_mem_monitor_t [#lv_mem_monitor_t] Heap information structure. | Member | Type | Description | | ------------------- | -------------------------- | ---------------------------- | | `total_size` | | Total heap size | | `free_cnt` | | | | `free_size` | | Size of available memory | | `free_biggest_size` | | | | `used_cnt` | | | | `max_used` | | Max size of Heap memory used | | `used_pct` | | Percentage used | | `frag_pct` | | Amount of fragmentation | * `lv_mem_monitor_core` — param `mon_p` * `lv_mem_monitor` — param `mon_p` Typedefs [#typedefs] lv_mem_pool_t [#lv_mem_pool_t] ```c title=" " lineNumbers=1 typedef void* lv_mem_pool_t ``` * `lv_mem_remove_pool` — param `pool` Dependencies [#dependencies]