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 "fnv1a.h"
  36 #include "macros.h"
  37
  38 #ifdef __cplusplus
  39 extern "C" {
  40 #endif
  41
  42 struct hash_entry {
  43    uint32_t hash;
  44    const void *key;
  45    void *data;
  46 };
  47
  48 struct hash_table {
  49    struct hash_entry *table;
  50    uint32_t (*key_hash_function)(const void *key);
  51    bool (*key_equals_function)(const void *a, const void *b);
  52    const void *deleted_key;
  53    uint32_t size;
  54    uint32_t rehash;
  55    uint64_t size_magic;
  56    uint64_t rehash_magic;
  57    uint32_t max_entries;
  58    uint32_t size_index;
  59    uint32_t entries;
  60    uint32_t deleted_entries;
  61 };
  62
  63 struct hash_table *
  64 _mesa_hash_table_create(void *mem_ctx,
  65                         uint32_t (*key_hash_function)(const void *key),
  66                         bool (*key_equals_function)(const void *a,
  67                                                     const void *b));
  68
  69 bool
  70 _mesa_hash_table_init(struct hash_table *ht,
  71                       void *mem_ctx,
  72                       uint32_t (*key_hash_function)(const void *key),
  73                       bool (*key_equals_function)(const void *a,
  74                                                   const void *b));
  75
  76 struct hash_table *
  77 _mesa_hash_table_clone(struct hash_table *src, void *dst_mem_ctx);
  78 void _mesa_hash_table_destroy(struct hash_table *ht,
  79                               void (*delete_function)(struct hash_entry *entry));
  80 void _mesa_hash_table_clear(struct hash_table *ht,
  81                             void (*delete_function)(struct hash_entry *entry));
  82 void _mesa_hash_table_set_deleted_key(struct hash_table *ht,
  83                                       const void *deleted_key);
  84
  85 static inline uint32_t _mesa_hash_table_num_entries(struct hash_table *ht)
  86 {
  87    return ht->entries;
  88 }
  89
  90 struct hash_entry *
  91 _mesa_hash_table_insert(struct hash_table *ht, const void *key, void *data);
  92 struct hash_entry *
  93 _mesa_hash_table_insert_pre_hashed(struct hash_table *ht, uint32_t hash,
  94                                    const void *key, void *data);
  95 struct hash_entry *
  96 _mesa_hash_table_search(struct hash_table *ht, const void *key);
  97 struct hash_entry *
  98 _mesa_hash_table_search_pre_hashed(struct hash_table *ht, uint32_t hash,
  99                                   const void *key);
 100 void _mesa_hash_table_remove(struct hash_table *ht,
 101                              struct hash_entry *entry);
 102 void _mesa_hash_table_remove_key(struct hash_table *ht,
 103                                  const void *key);
 104
 105 struct hash_entry *_mesa_hash_table_next_entry(struct hash_table *ht,
 106                                                struct hash_entry *entry);
 107 struct hash_entry *
 108 _mesa_hash_table_random_entry(struct hash_table *ht,
 109                               bool (*predicate)(struct hash_entry *entry));
 110
 111 uint32_t _mesa_hash_data(const void *data, size_t size);
 112 uint32_t _mesa_hash_string(const void *key);
 113 bool _mesa_key_string_equal(const void *a, const void *b);
 114 bool _mesa_key_pointer_equal(const void *a, const void *b);
 115
 116 static inline uint32_t _mesa_key_hash_string(const void *key)
 117 {
 118    return _mesa_hash_string((const char *)key);
 119 }
 120
 121 static inline uint32_t _mesa_hash_pointer(const void *pointer)
 122 {
 123    uintptr_t num = (uintptr_t) pointer;
 124    return (uint32_t) ((num >> 2) ^ (num >> 6) ^ (num >> 10) ^ (num >> 14));
 125 }
 126
 127 struct hash_table *
 128 _mesa_pointer_hash_table_create(void *mem_ctx);
 129
 130 /**
 131  * This foreach function is safe against deletion (which just replaces
 132  * an entry's data with the deleted marker), but not against insertion
 133  * (which may rehash the table, making entry a dangling pointer).
 134  */
 135 #define hash_table_foreach(ht, entry)                                      \
 136    for (struct hash_entry *entry = _mesa_hash_table_next_entry(ht, NULL);  \
 137         entry != NULL;                                                     \
 138         entry = _mesa_hash_table_next_entry(ht, entry))
 139
 140 static inline void
 141 hash_table_call_foreach(struct hash_table *ht,
 142                         void (*callback)(const void *key,
 143                                          void *data,
 144                                          void *closure),
 145                         void *closure)
 146 {
 147    hash_table_foreach(ht, entry)
 148       callback(entry->key, entry->data, closure);
 149 }
 150
 151 /**
 152  * Hash table wrapper which supports 64-bit keys.
 153  */
 154 struct hash_table_u64 {
 155    struct hash_table *table;
 156    void *freed_key_data;
 157    void *deleted_key_data;
 158 };
 159
 160 struct hash_table_u64 *
 161 _mesa_hash_table_u64_create(void *mem_ctx);
 162
 163 void
 164 _mesa_hash_table_u64_destroy(struct hash_table_u64 *ht,
 165                              void (*delete_function)(struct hash_entry *entry));
 166
 167 void
 168 _mesa_hash_table_u64_insert(struct hash_table_u64 *ht, uint64_t key,
 169                             void *data);
 170
 171 void *
 172 _mesa_hash_table_u64_search(struct hash_table_u64 *ht, uint64_t key);
 173
 174 void
 175 _mesa_hash_table_u64_remove(struct hash_table_u64 *ht, uint64_t key);
 176
 177 void
 178 _mesa_hash_table_u64_clear(struct hash_table_u64 *ht,
 179                            void (*delete_function)(struct hash_entry *entry));
 180
 181 #ifdef __cplusplus
 182 } /* extern C */
 183 #endif
 184
 185 #endif /* _HASH_TABLE_H */