src/util/hash_table.h

   1 /*
   2  * Copyright © 2009,2012 Intel Corporation
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  21  * IN THE SOFTWARE.
  22  *
  23  * Authors:
  24  *    Eric Anholt <eric@anholt.net>
  25  *
  26  */
  27
  28 #ifndef _HASH_TABLE_H
  29 #define _HASH_TABLE_H
  30
  31 #include <stdlib.h>
  32 #include <inttypes.h>
  33 #include <stdbool.h>
  34 #include "c99_compat.h"
  35 #include "macros.h"
  36
  37 #ifdef __cplusplus
  38 extern "C" {
  39 #endif
  40
  41 struct hash_entry {
  42    uint32_t hash;
  43    const void *key;
  44    void *data;
  45 };
  46
  47 struct hash_table {
  48    struct hash_entry *table;
  49    uint32_t (*key_hash_function)(const void *key);
  50    bool (*key_equals_function)(const void *a, const void *b);
  51    const void *deleted_key;
  52    uint32_t size;
  53    uint32_t rehash;
  54    uint64_t size_magic;
  55    uint64_t rehash_magic;
  56    uint32_t max_entries;
  57    uint32_t size_index;
  58    uint32_t entries;
  59    uint32_t deleted_entries;
  60 };
  61
  62 struct hash_table *
  63 _mesa_hash_table_create(void *mem_ctx,
  64                         uint32_t (*key_hash_function)(const void *key),
  65                         bool (*key_equals_function)(const void *a,
  66                                                     const void *b));
  67
  68 bool
  69 _mesa_hash_table_init(struct hash_table *ht,
  70                       void *mem_ctx,
  71                       uint32_t (*key_hash_function)(const void *key),
  72                       bool (*key_equals_function)(const void *a,
  73                                                   const void *b));
  74
  75 struct hash_table *
  76 _mesa_hash_table_clone(struct hash_table *src, void *dst_mem_ctx);
  77 void _mesa_hash_table_destroy(struct hash_table *ht,
  78                               void (*delete_function)(struct hash_entry *entry));
  79 void _mesa_hash_table_clear(struct hash_table *ht,
  80                             void (*delete_function)(struct hash_entry *entry));
  81 void _mesa_hash_table_set_deleted_key(struct hash_table *ht,
  82                                       const void *deleted_key);
  83
  84 static inline uint32_t _mesa_hash_table_num_entries(struct hash_table *ht)
  85 {
  86    return ht->entries;
  87 }
  88
  89 struct hash_entry *
  90 _mesa_hash_table_insert(struct hash_table *ht, const void *key, void *data);
  91 struct hash_entry *
  92 _mesa_hash_table_insert_pre_hashed(struct hash_table *ht, uint32_t hash,
  93                                    const void *key, void *data);
  94 struct hash_entry *
  95 _mesa_hash_table_search(struct hash_table *ht, const void *key);
  96 struct hash_entry *
  97 _mesa_hash_table_search_pre_hashed(struct hash_table *ht, uint32_t hash,
  98                                   const void *key);
  99 void _mesa_hash_table_remove(struct hash_table *ht,
 100                              struct hash_entry *entry);
 101 void _mesa_hash_table_remove_key(struct hash_table *ht,
 102                                  const void *key);
 103
 104 struct hash_entry *_mesa_hash_table_next_entry(struct hash_table *ht,
 105                                                struct hash_entry *entry);
 106 struct hash_entry *
 107 _mesa_hash_table_random_entry(struct hash_table *ht,
 108                               bool (*predicate)(struct hash_entry *entry));
 109
 110 uint32_t _mesa_hash_data(const void *data, size_t size);
 111 uint32_t _mesa_hash_string(const void *key);
 112 bool _mesa_key_string_equal(const void *a, const void *b);
 113 bool _mesa_key_pointer_equal(const void *a, const void *b);
 114
 115 static inline uint32_t _mesa_key_hash_string(const void *key)
 116 {
 117    return _mesa_hash_string((const char *)key);
 118 }
 119
 120 static inline uint32_t _mesa_hash_pointer(const void *pointer)
 121 {
 122    uintptr_t num = (uintptr_t) pointer;
 123    return (uint32_t) ((num >> 2) ^ (num >> 6) ^ (num >> 10) ^ (num >> 14));
 124 }
 125
 126 struct hash_table *
 127 _mesa_pointer_hash_table_create(void *mem_ctx);
 128
 129 enum {
 130    _mesa_fnv32_1a_offset_bias = 2166136261u,
 131 };
 132
 133 static inline uint32_t
 134 _mesa_fnv32_1a_accumulate_block(uint32_t hash, const void *data, size_t size)
 135 {
 136    const uint8_t *bytes = (const uint8_t *)data;
 137
 138    while (size-- != 0) {
 139       hash ^= *bytes;
 140       hash = hash * 0x01000193;
 141       bytes++;
 142    }
 143
 144    return hash;
 145 }
 146
 147 #define _mesa_fnv32_1a_accumulate(hash, expr) \
 148    _mesa_fnv32_1a_accumulate_block(hash, &(expr), sizeof(expr))
 149
 150 /**
 151  * This foreach function is safe against deletion (which just replaces
 152  * an entry's data with the deleted marker), but not against insertion
 153  * (which may rehash the table, making entry a dangling pointer).
 154  */
 155 #define hash_table_foreach(ht, entry)                                      \
 156    for (struct hash_entry *entry = _mesa_hash_table_next_entry(ht, NULL);  \
 157         entry != NULL;                                                     \
 158         entry = _mesa_hash_table_next_entry(ht, entry))
 159
 160 static inline void
 161 hash_table_call_foreach(struct hash_table *ht,
 162                         void (*callback)(const void *key,
 163                                          void *data,
 164                                          void *closure),
 165                         void *closure)
 166 {
 167    hash_table_foreach(ht, entry)
 168       callback(entry->key, entry->data, closure);
 169 }
 170
 171 /**
 172  * Hash table wrapper which supports 64-bit keys.
 173  */
 174 struct hash_table_u64 {
 175    struct hash_table *table;
 176    void *freed_key_data;
 177    void *deleted_key_data;
 178 };
 179
 180 struct hash_table_u64 *
 181 _mesa_hash_table_u64_create(void *mem_ctx);
 182
 183 void
 184 _mesa_hash_table_u64_destroy(struct hash_table_u64 *ht,
 185                              void (*delete_function)(struct hash_entry *entry));
 186
 187 void
 188 _mesa_hash_table_u64_insert(struct hash_table_u64 *ht, uint64_t key,
 189                             void *data);
 190
 191 void *
 192 _mesa_hash_table_u64_search(struct hash_table_u64 *ht, uint64_t key);
 193
 194 void
 195 _mesa_hash_table_u64_remove(struct hash_table_u64 *ht, uint64_t key);
 196
 197 void
 198 _mesa_hash_table_u64_clear(struct hash_table_u64 *ht,
 199                            void (*delete_function)(struct hash_entry *entry));
 200
 201 #ifdef __cplusplus
 202 } /* extern C */
 203 #endif
 204
 205 #endif /* _HASH_TABLE_H */