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Diffstat (limited to 'src/libbasic/hashmap.h')
| -rw-r--r-- | src/libbasic/hashmap.h | 372 |
1 files changed, 372 insertions, 0 deletions
diff --git a/src/libbasic/hashmap.h b/src/libbasic/hashmap.h new file mode 100644 index 0000000000..6d1ae48b21 --- /dev/null +++ b/src/libbasic/hashmap.h @@ -0,0 +1,372 @@ +#pragma once + +/*** + This file is part of systemd. + + Copyright 2010 Lennart Poettering + Copyright 2014 Michal Schmidt + + systemd is free software; you can redistribute it and/or modify it + under the terms of the GNU Lesser General Public License as published by + the Free Software Foundation; either version 2.1 of the License, or + (at your option) any later version. + + systemd is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with systemd; If not, see <http://www.gnu.org/licenses/>. +***/ + +#include <limits.h> +#include <stdbool.h> +#include <stddef.h> + +#include "hash-funcs.h" +#include "macro.h" +#include "util.h" + +/* + * A hash table implementation. As a minor optimization a NULL hashmap object + * will be treated as empty hashmap for all read operations. That way it is not + * necessary to instantiate an object for each Hashmap use. + * + * If ENABLE_DEBUG_HASHMAP is defined (by configuring with --enable-debug=hashmap), + * the implemention will: + * - store extra data for debugging and statistics (see tools/gdb-sd_dump_hashmaps.py) + * - perform extra checks for invalid use of iterators + */ + +#define HASH_KEY_SIZE 16 + +/* The base type for all hashmap and set types. Many functions in the + * implementation take (HashmapBase*) parameters and are run-time polymorphic, + * though the API is not meant to be polymorphic (do not call functions + * internal_*() directly). */ +typedef struct HashmapBase HashmapBase; + +/* Specific hashmap/set types */ +typedef struct Hashmap Hashmap; /* Maps keys to values */ +typedef struct OrderedHashmap OrderedHashmap; /* Like Hashmap, but also remembers entry insertion order */ +typedef struct Set Set; /* Stores just keys */ + +/* Ideally the Iterator would be an opaque struct, but it is instantiated + * by hashmap users, so the definition has to be here. Do not use its fields + * directly. */ +typedef struct { + unsigned idx; /* index of an entry to be iterated next */ + const void *next_key; /* expected value of that entry's key pointer */ +#ifdef ENABLE_DEBUG_HASHMAP + unsigned put_count; /* hashmap's put_count recorded at start of iteration */ + unsigned rem_count; /* hashmap's rem_count in previous iteration */ + unsigned prev_idx; /* idx in previous iteration */ +#endif +} Iterator; + +#define _IDX_ITERATOR_FIRST (UINT_MAX - 1) +#define ITERATOR_FIRST ((Iterator) { .idx = _IDX_ITERATOR_FIRST, .next_key = NULL }) + +/* Macros for type checking */ +#define PTR_COMPATIBLE_WITH_HASHMAP_BASE(h) \ + (__builtin_types_compatible_p(typeof(h), HashmapBase*) || \ + __builtin_types_compatible_p(typeof(h), Hashmap*) || \ + __builtin_types_compatible_p(typeof(h), OrderedHashmap*) || \ + __builtin_types_compatible_p(typeof(h), Set*)) + +#define PTR_COMPATIBLE_WITH_PLAIN_HASHMAP(h) \ + (__builtin_types_compatible_p(typeof(h), Hashmap*) || \ + __builtin_types_compatible_p(typeof(h), OrderedHashmap*)) \ + +#define HASHMAP_BASE(h) \ + __builtin_choose_expr(PTR_COMPATIBLE_WITH_HASHMAP_BASE(h), \ + (HashmapBase*)(h), \ + (void)0) + +#define PLAIN_HASHMAP(h) \ + __builtin_choose_expr(PTR_COMPATIBLE_WITH_PLAIN_HASHMAP(h), \ + (Hashmap*)(h), \ + (void)0) + +#ifdef ENABLE_DEBUG_HASHMAP +# define HASHMAP_DEBUG_PARAMS , const char *func, const char *file, int line +# define HASHMAP_DEBUG_SRC_ARGS , __func__, __FILE__, __LINE__ +# define HASHMAP_DEBUG_PASS_ARGS , func, file, line +#else +# define HASHMAP_DEBUG_PARAMS +# define HASHMAP_DEBUG_SRC_ARGS +# define HASHMAP_DEBUG_PASS_ARGS +#endif + +Hashmap *internal_hashmap_new(const struct hash_ops *hash_ops HASHMAP_DEBUG_PARAMS); +OrderedHashmap *internal_ordered_hashmap_new(const struct hash_ops *hash_ops HASHMAP_DEBUG_PARAMS); +#define hashmap_new(ops) internal_hashmap_new(ops HASHMAP_DEBUG_SRC_ARGS) +#define ordered_hashmap_new(ops) internal_ordered_hashmap_new(ops HASHMAP_DEBUG_SRC_ARGS) + +HashmapBase *internal_hashmap_free(HashmapBase *h); +static inline Hashmap *hashmap_free(Hashmap *h) { + return (void*)internal_hashmap_free(HASHMAP_BASE(h)); +} +static inline OrderedHashmap *ordered_hashmap_free(OrderedHashmap *h) { + return (void*)internal_hashmap_free(HASHMAP_BASE(h)); +} + +HashmapBase *internal_hashmap_free_free(HashmapBase *h); +static inline Hashmap *hashmap_free_free(Hashmap *h) { + return (void*)internal_hashmap_free_free(HASHMAP_BASE(h)); +} +static inline OrderedHashmap *ordered_hashmap_free_free(OrderedHashmap *h) { + return (void*)internal_hashmap_free_free(HASHMAP_BASE(h)); +} + +Hashmap *hashmap_free_free_free(Hashmap *h); +static inline OrderedHashmap *ordered_hashmap_free_free_free(OrderedHashmap *h) { + return (void*)hashmap_free_free_free(PLAIN_HASHMAP(h)); +} + +HashmapBase *internal_hashmap_copy(HashmapBase *h); +static inline Hashmap *hashmap_copy(Hashmap *h) { + return (Hashmap*) internal_hashmap_copy(HASHMAP_BASE(h)); +} +static inline OrderedHashmap *ordered_hashmap_copy(OrderedHashmap *h) { + return (OrderedHashmap*) internal_hashmap_copy(HASHMAP_BASE(h)); +} + +int internal_hashmap_ensure_allocated(Hashmap **h, const struct hash_ops *hash_ops HASHMAP_DEBUG_PARAMS); +int internal_ordered_hashmap_ensure_allocated(OrderedHashmap **h, const struct hash_ops *hash_ops HASHMAP_DEBUG_PARAMS); +#define hashmap_ensure_allocated(h, ops) internal_hashmap_ensure_allocated(h, ops HASHMAP_DEBUG_SRC_ARGS) +#define ordered_hashmap_ensure_allocated(h, ops) internal_ordered_hashmap_ensure_allocated(h, ops HASHMAP_DEBUG_SRC_ARGS) + +int hashmap_put(Hashmap *h, const void *key, void *value); +static inline int ordered_hashmap_put(OrderedHashmap *h, const void *key, void *value) { + return hashmap_put(PLAIN_HASHMAP(h), key, value); +} + +int hashmap_update(Hashmap *h, const void *key, void *value); +static inline int ordered_hashmap_update(OrderedHashmap *h, const void *key, void *value) { + return hashmap_update(PLAIN_HASHMAP(h), key, value); +} + +int hashmap_replace(Hashmap *h, const void *key, void *value); +static inline int ordered_hashmap_replace(OrderedHashmap *h, const void *key, void *value) { + return hashmap_replace(PLAIN_HASHMAP(h), key, value); +} + +void *internal_hashmap_get(HashmapBase *h, const void *key); +static inline void *hashmap_get(Hashmap *h, const void *key) { + return internal_hashmap_get(HASHMAP_BASE(h), key); +} +static inline void *ordered_hashmap_get(OrderedHashmap *h, const void *key) { + return internal_hashmap_get(HASHMAP_BASE(h), key); +} + +void *hashmap_get2(Hashmap *h, const void *key, void **rkey); +static inline void *ordered_hashmap_get2(OrderedHashmap *h, const void *key, void **rkey) { + return hashmap_get2(PLAIN_HASHMAP(h), key, rkey); +} + +bool internal_hashmap_contains(HashmapBase *h, const void *key); +static inline bool hashmap_contains(Hashmap *h, const void *key) { + return internal_hashmap_contains(HASHMAP_BASE(h), key); +} +static inline bool ordered_hashmap_contains(OrderedHashmap *h, const void *key) { + return internal_hashmap_contains(HASHMAP_BASE(h), key); +} + +void *internal_hashmap_remove(HashmapBase *h, const void *key); +static inline void *hashmap_remove(Hashmap *h, const void *key) { + return internal_hashmap_remove(HASHMAP_BASE(h), key); +} +static inline void *ordered_hashmap_remove(OrderedHashmap *h, const void *key) { + return internal_hashmap_remove(HASHMAP_BASE(h), key); +} + +void *hashmap_remove2(Hashmap *h, const void *key, void **rkey); +static inline void *ordered_hashmap_remove2(OrderedHashmap *h, const void *key, void **rkey) { + return hashmap_remove2(PLAIN_HASHMAP(h), key, rkey); +} + +void *hashmap_remove_value(Hashmap *h, const void *key, void *value); +static inline void *ordered_hashmap_remove_value(OrderedHashmap *h, const void *key, void *value) { + return hashmap_remove_value(PLAIN_HASHMAP(h), key, value); +} + +int hashmap_remove_and_put(Hashmap *h, const void *old_key, const void *new_key, void *value); +static inline int ordered_hashmap_remove_and_put(OrderedHashmap *h, const void *old_key, const void *new_key, void *value) { + return hashmap_remove_and_put(PLAIN_HASHMAP(h), old_key, new_key, value); +} + +int hashmap_remove_and_replace(Hashmap *h, const void *old_key, const void *new_key, void *value); +static inline int ordered_hashmap_remove_and_replace(OrderedHashmap *h, const void *old_key, const void *new_key, void *value) { + return hashmap_remove_and_replace(PLAIN_HASHMAP(h), old_key, new_key, value); +} + +/* Since merging data from a OrderedHashmap into a Hashmap or vice-versa + * should just work, allow this by having looser type-checking here. */ +int internal_hashmap_merge(Hashmap *h, Hashmap *other); +#define hashmap_merge(h, other) internal_hashmap_merge(PLAIN_HASHMAP(h), PLAIN_HASHMAP(other)) +#define ordered_hashmap_merge(h, other) hashmap_merge(h, other) + +int internal_hashmap_reserve(HashmapBase *h, unsigned entries_add); +static inline int hashmap_reserve(Hashmap *h, unsigned entries_add) { + return internal_hashmap_reserve(HASHMAP_BASE(h), entries_add); +} +static inline int ordered_hashmap_reserve(OrderedHashmap *h, unsigned entries_add) { + return internal_hashmap_reserve(HASHMAP_BASE(h), entries_add); +} + +int internal_hashmap_move(HashmapBase *h, HashmapBase *other); +/* Unlike hashmap_merge, hashmap_move does not allow mixing the types. */ +static inline int hashmap_move(Hashmap *h, Hashmap *other) { + return internal_hashmap_move(HASHMAP_BASE(h), HASHMAP_BASE(other)); +} +static inline int ordered_hashmap_move(OrderedHashmap *h, OrderedHashmap *other) { + return internal_hashmap_move(HASHMAP_BASE(h), HASHMAP_BASE(other)); +} + +int internal_hashmap_move_one(HashmapBase *h, HashmapBase *other, const void *key); +static inline int hashmap_move_one(Hashmap *h, Hashmap *other, const void *key) { + return internal_hashmap_move_one(HASHMAP_BASE(h), HASHMAP_BASE(other), key); +} +static inline int ordered_hashmap_move_one(OrderedHashmap *h, OrderedHashmap *other, const void *key) { + return internal_hashmap_move_one(HASHMAP_BASE(h), HASHMAP_BASE(other), key); +} + +unsigned internal_hashmap_size(HashmapBase *h) _pure_; +static inline unsigned hashmap_size(Hashmap *h) { + return internal_hashmap_size(HASHMAP_BASE(h)); +} +static inline unsigned ordered_hashmap_size(OrderedHashmap *h) { + return internal_hashmap_size(HASHMAP_BASE(h)); +} + +static inline bool hashmap_isempty(Hashmap *h) { + return hashmap_size(h) == 0; +} +static inline bool ordered_hashmap_isempty(OrderedHashmap *h) { + return ordered_hashmap_size(h) == 0; +} + +unsigned internal_hashmap_buckets(HashmapBase *h) _pure_; +static inline unsigned hashmap_buckets(Hashmap *h) { + return internal_hashmap_buckets(HASHMAP_BASE(h)); +} +static inline unsigned ordered_hashmap_buckets(OrderedHashmap *h) { + return internal_hashmap_buckets(HASHMAP_BASE(h)); +} + +bool internal_hashmap_iterate(HashmapBase *h, Iterator *i, void **value, const void **key); +static inline bool hashmap_iterate(Hashmap *h, Iterator *i, void **value, const void **key) { + return internal_hashmap_iterate(HASHMAP_BASE(h), i, value, key); +} +static inline bool ordered_hashmap_iterate(OrderedHashmap *h, Iterator *i, void **value, const void **key) { + return internal_hashmap_iterate(HASHMAP_BASE(h), i, value, key); +} + +void internal_hashmap_clear(HashmapBase *h); +static inline void hashmap_clear(Hashmap *h) { + internal_hashmap_clear(HASHMAP_BASE(h)); +} +static inline void ordered_hashmap_clear(OrderedHashmap *h) { + internal_hashmap_clear(HASHMAP_BASE(h)); +} + +void internal_hashmap_clear_free(HashmapBase *h); +static inline void hashmap_clear_free(Hashmap *h) { + internal_hashmap_clear_free(HASHMAP_BASE(h)); +} +static inline void ordered_hashmap_clear_free(OrderedHashmap *h) { + internal_hashmap_clear_free(HASHMAP_BASE(h)); +} + +void hashmap_clear_free_free(Hashmap *h); +static inline void ordered_hashmap_clear_free_free(OrderedHashmap *h) { + hashmap_clear_free_free(PLAIN_HASHMAP(h)); +} + +/* + * Note about all *_first*() functions + * + * For plain Hashmaps and Sets the order of entries is undefined. + * The functions find whatever entry is first in the implementation + * internal order. + * + * Only for OrderedHashmaps the order is well defined and finding + * the first entry is O(1). + */ + +void *internal_hashmap_steal_first(HashmapBase *h); +static inline void *hashmap_steal_first(Hashmap *h) { + return internal_hashmap_steal_first(HASHMAP_BASE(h)); +} +static inline void *ordered_hashmap_steal_first(OrderedHashmap *h) { + return internal_hashmap_steal_first(HASHMAP_BASE(h)); +} + +void *internal_hashmap_steal_first_key(HashmapBase *h); +static inline void *hashmap_steal_first_key(Hashmap *h) { + return internal_hashmap_steal_first_key(HASHMAP_BASE(h)); +} +static inline void *ordered_hashmap_steal_first_key(OrderedHashmap *h) { + return internal_hashmap_steal_first_key(HASHMAP_BASE(h)); +} + +void *internal_hashmap_first_key(HashmapBase *h) _pure_; +static inline void *hashmap_first_key(Hashmap *h) { + return internal_hashmap_first_key(HASHMAP_BASE(h)); +} +static inline void *ordered_hashmap_first_key(OrderedHashmap *h) { + return internal_hashmap_first_key(HASHMAP_BASE(h)); +} + +void *internal_hashmap_first(HashmapBase *h) _pure_; +static inline void *hashmap_first(Hashmap *h) { + return internal_hashmap_first(HASHMAP_BASE(h)); +} +static inline void *ordered_hashmap_first(OrderedHashmap *h) { + return internal_hashmap_first(HASHMAP_BASE(h)); +} + +/* no hashmap_next */ +void *ordered_hashmap_next(OrderedHashmap *h, const void *key); + +char **internal_hashmap_get_strv(HashmapBase *h); +static inline char **hashmap_get_strv(Hashmap *h) { + return internal_hashmap_get_strv(HASHMAP_BASE(h)); +} +static inline char **ordered_hashmap_get_strv(OrderedHashmap *h) { + return internal_hashmap_get_strv(HASHMAP_BASE(h)); +} + +/* + * Hashmaps are iterated in unpredictable order. + * OrderedHashmaps are an exception to this. They are iterated in the order + * the entries were inserted. + * It is safe to remove the current entry. + */ +#define HASHMAP_FOREACH(e, h, i) \ + for ((i) = ITERATOR_FIRST; hashmap_iterate((h), &(i), (void**)&(e), NULL); ) + +#define ORDERED_HASHMAP_FOREACH(e, h, i) \ + for ((i) = ITERATOR_FIRST; ordered_hashmap_iterate((h), &(i), (void**)&(e), NULL); ) + +#define HASHMAP_FOREACH_KEY(e, k, h, i) \ + for ((i) = ITERATOR_FIRST; hashmap_iterate((h), &(i), (void**)&(e), (const void**) &(k)); ) + +#define ORDERED_HASHMAP_FOREACH_KEY(e, k, h, i) \ + for ((i) = ITERATOR_FIRST; ordered_hashmap_iterate((h), &(i), (void**)&(e), (const void**) &(k)); ) + +DEFINE_TRIVIAL_CLEANUP_FUNC(Hashmap*, hashmap_free); +DEFINE_TRIVIAL_CLEANUP_FUNC(Hashmap*, hashmap_free_free); +DEFINE_TRIVIAL_CLEANUP_FUNC(Hashmap*, hashmap_free_free_free); +DEFINE_TRIVIAL_CLEANUP_FUNC(OrderedHashmap*, ordered_hashmap_free); +DEFINE_TRIVIAL_CLEANUP_FUNC(OrderedHashmap*, ordered_hashmap_free_free); +DEFINE_TRIVIAL_CLEANUP_FUNC(OrderedHashmap*, ordered_hashmap_free_free_free); + +#define _cleanup_hashmap_free_ _cleanup_(hashmap_freep) +#define _cleanup_hashmap_free_free_ _cleanup_(hashmap_free_freep) +#define _cleanup_hashmap_free_free_free_ _cleanup_(hashmap_free_free_freep) +#define _cleanup_ordered_hashmap_free_ _cleanup_(ordered_hashmap_freep) +#define _cleanup_ordered_hashmap_free_free_ _cleanup_(ordered_hashmap_free_freep) +#define _cleanup_ordered_hashmap_free_free_free_ _cleanup_(ordered_hashmap_free_free_freep) |