ref: 21ffcc74db3077b2cf298ace7445e5993300b2fe
dir: /include/hashmap.h/
/* * This file is part of RGBDS. * * Copyright (c) 1997-2019, Carsten Sorensen and RGBDS contributors. * * SPDX-License-Identifier: MIT */ /* Generic hashmap implementation (C++ templates are calling...) */ #ifndef RGBDS_LINK_HASHMAP_H #define RGBDS_LINK_HASHMAP_H #include <assert.h> #define HASH_NB_BITS 32 #define HALF_HASH_NB_BITS 16 _Static_assert(HALF_HASH_NB_BITS * 2 == HASH_NB_BITS, ""); #define HASHMAP_NB_BUCKETS (1 << HALF_HASH_NB_BITS) /* HashMapEntry is internal, please do not attempt to use it */ typedef struct HashMapEntry *HashMap[HASHMAP_NB_BUCKETS]; /** * Adds an element to a hashmap. * @warning Adding a new element with an already-present key will not cause an * error, this must be handled externally. * @warning Inserting a NULL will make `hash_GetElement`'s return ambiguous! * @param map The HashMap to add the element to * @param key The key with which the element will be stored and retrieved * @param element The element to add * @return True if a collision occurred (for statistics) */ bool hash_AddElement(HashMap map, char const *key, void *element); /** * Removes an element from a hashmap. * @param map The HashMap to remove the element from * @param key The key to search the element with * @return True if the element was found and removed */ bool hash_RemoveElement(HashMap map, char const *key); /** * Finds an element in a hashmap. * @param map The map to consider the elements of * @param key The key to search an element for * @return A pointer to the element, or NULL if not found. (NULL can be returned * if such an element was added, but that sounds pretty silly.) */ void *hash_GetElement(HashMap const map, char const *key); /** * Executes a function on each element in a hashmap. * @param map The map to consider the elements of * @param func The function to run. The first argument will be the element, * the second will be `arg`. * @param arg An argument to be passed to all function calls */ void hash_ForEach(HashMap const map, void (*func)(void *, void *), void *arg); /** * Cleanly empties a hashmap from its contents. * This does not `free` the data structure itself! * @param map The map to empty */ void hash_EmptyMap(HashMap map); #endif /* RGBDS_LINK_HASHMAP_H */