summaryrefslogtreecommitdiff
path: root/src/libbasic/include/basic/hashmap.h
blob: 6d1ae48b213b76fbe4da1b4c01fc5ebb3d8e13e9 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
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)