lv_cache_private.h

Typedefs

typedef struct _lv_cache_ops_t lv_cache_ops_t

typedef struct _lv_cache_class_t lv_cache_class_t

typedef int8_t lv_cache_compare_res_t

typedef bool (*lv_cache_create_cb_t)(void *node, void *user_data)

typedef void (*lv_cache_free_cb_t)(void *node, void *user_data)

typedef lv_cache_compare_res_t (*lv_cache_compare_cb_t)(const void *a, const void *b)

typedef void *(*lv_cache_alloc_cb_t)(void)

The cache instance allocation function, used by the cache class to allocate memory for cache instances.

Return:

It should return a pointer to the allocated instance.

typedef bool (*lv_cache_init_cb_t)(lv_cache_t *cache)

The cache instance initialization function, used by the cache class to initialize the cache instance.

Return:

It should return true if the initialization is successful, false otherwise.

typedef void (*lv_cache_destroy_cb_t)(lv_cache_t *cache, void *user_data)

The cache instance destruction function, used by the cache class to destroy the cache instance.

typedef lv_cache_entry_t *(*lv_cache_get_cb_t)(lv_cache_t *cache, const void *key, void *user_data)

The cache get function, used by the cache class to get a cache entry by its key.

Return:

NULL if the key is not found.

typedef lv_cache_entry_t *(*lv_cache_add_cb_t)(lv_cache_t *cache, const void *key, void *user_data)

The cache add function, used by the cache class to add a cache entry with a given key. This function only cares about how to add the entry, it doesn't check if the entry already exists and doesn't care about is it a victim or not.

Return:

the added cache entry, or NULL if the entry is not added.

typedef void (*lv_cache_remove_cb_t)(lv_cache_t *cache, lv_cache_entry_t *entry, void *user_data)

The cache remove function, used by the cache class to remove a cache entry from the cache but doesn't free the memory.. This function only cares about how to remove the entry, it doesn't care about is it a victim or not.

typedef void (*lv_cache_drop_cb_t)(lv_cache_t *cache, const void *key, void *user_data)

The cache drop function, used by the cache class to remove a cache entry from the cache and free the memory.

typedef void (*lv_cache_drop_all_cb_t)(lv_cache_t *cache, void *user_data)

The cache drop all function, used by the cache class to remove all cache entries from the cache and free the memory.

typedef lv_cache_entry_t *(*lv_cache_get_victim_cb)(lv_cache_t *cache, void *user_data)

The cache get victim function, used by the cache class to get a victim entry to be evicted.

typedef lv_cache_reserve_cond_res_t (*lv_cache_reserve_cond_cb)(lv_cache_t *cache, const void *key, size_t size, void *user_data)

The cache reserve condition function, used by the cache class to check if a new entry can be added to the cache without exceeding its maximum size. See lv_cache_reserve_cond_res_t for the possible results.

typedef lv_iter_t *(*lv_cache_iter_create_cb)(lv_cache_t *cache)

The cache iterator creation function, used by the cache class to create an iterator for the cache.

Return:

A pointer to the created iterator, or NULL if the iterator cannot be created.

typedef struct _lv_cache_slot_size_t lv_cache_slot_size_t

Enums

enum lv_cache_reserve_cond_res_t

The result of the cache reserve condition callback

Values:

enumerator LV_CACHE_RESERVE_COND_OK

The condition is met and no entries need to be evicted

enumerator LV_CACHE_RESERVE_COND_TOO_LARGE

The condition is not met and the reserve size is too large

enumerator LV_CACHE_RESERVE_COND_NEED_VICTIM

The condition is not met and a victim is needed to be evicted

enumerator LV_CACHE_RESERVE_COND_ERROR

An error occurred while checking the condition

struct _lv_cache_ops_t

#include <lv_cache_private.h>

The cache operations struct

Public Members

lv_cache_compare_cb_t compare_cb

Compare function for keys

lv_cache_create_cb_t create_cb

Create function for nodes

lv_cache_free_cb_t free_cb

Free function for nodes

struct _lv_cache_t

#include <lv_cache_private.h>

The cache entry struct

Public Members

const lv_cache_class_t *clz

Cache class. There are two built-in classes:

• lv_cache_class_lru_rb_count for LRU-based cache with count-based eviction policy.

• lv_cache_class_lru_rb_size for LRU-based cache with size-based eviction policy.

uint32_t node_size

Size of a node

uint32_t max_size

Maximum size of the cache

uint32_t size

Current size of the cache

lv_cache_ops_t ops

Cache operations struct _lv_cache_ops_t

lv_mutex_t lock

Cache lock used to protect the cache in multithreading environments

const char *name

Name of the cache

struct _lv_cache_class_t

#include <lv_cache_private.h>

Cache class struct for building custom cache classes

Examples:

• lv_cache_class_lru_rb_count for LRU-based cache with count-based eviction policy.

• lv_cache_class_lru_rb_size for LRU-based cache with size-based eviction policy.

Public Members

lv_cache_alloc_cb_t alloc_cb

The allocation function for cache entries

lv_cache_init_cb_t init_cb

The initialization function for cache entries

lv_cache_destroy_cb_t destroy_cb

The destruction function for cache entries

lv_cache_get_cb_t get_cb

The get function for cache entries

lv_cache_add_cb_t add_cb

The add function for cache entries

lv_cache_remove_cb_t remove_cb

The remove function for cache entries

lv_cache_drop_cb_t drop_cb

The drop function for cache entries

lv_cache_drop_all_cb_t drop_all_cb

The drop all function for cache entries

lv_cache_get_victim_cb get_victim_cb

The get victim function for cache entries

lv_cache_reserve_cond_cb reserve_cond_cb

The reserve condition function for cache entries

lv_cache_iter_create_cb iter_create_cb

The iterator creation function for cache entries

struct _lv_cache_slot_size_t

#include <lv_cache_private.h>

Cache entry slot struct

To add new fields to the cache entry, add them to a new struct and add it to the first field of the cache data struct. And this one is a size slot for the cache entry.

Public Members

size_t size