librb/include/rb_dictionary.h

   1 /*
   2  * Solanum: a slightly advanced ircd
   3  * rb_dictionary.h: Dictionary-based storage.
   4  *
   5  * Copyright (c) 2007 William Pitcock <nenolod -at- sacredspiral.co.uk>
   6  * Copyright (c) 2007 Jilles Tjoelker <jilles -at- stack.nl>
   7  *
   8  * Permission to use, copy, modify, and/or distribute this software for any
   9  * purpose with or without fee is hereby granted, provided that the above
  10  * copyright notice and this permission notice is present in all copies.
  11  *
  12  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  13  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  14  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  15  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
  16  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  17  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  18  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  19  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  20  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  21  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  22  * POSSIBILITY OF SUCH DAMAGE.
  23  */
  24
  25 #ifndef __RB_DICTIONARY_H__
  26 #define __RB_DICTIONARY_H__
  27
  28 #include "librb-config.h"
  29
  30 typedef struct rb_dictionary rb_dictionary;
  31 typedef struct rb_dictionary_element rb_dictionary_element;
  32 typedef struct rb_dictionary_iter rb_dictionary_iter;
  33
  34 struct rb_dictionary;
  35
  36 typedef int (*DCF)(/* const void *a, const void *b */);
  37
  38 struct rb_dictionary_element
  39 {
  40         rb_dictionary_element *left, *right, *prev, *next;
  41         void *data;
  42         const void *key;
  43         int position;
  44 };
  45
  46 struct rb_dictionary_iter
  47 {
  48         rb_dictionary_element *cur, *next;
  49 };
  50
  51 /*
  52  * this is a convenience macro for inlining iteration of dictionaries.
  53  */
  54 #define RB_DICTIONARY_FOREACH(element, state, dict) for (rb_dictionary_foreach_start((dict), (state)); (element = rb_dictionary_foreach_cur((dict), (state))); rb_dictionary_foreach_next((dict), (state)))
  55
  56 /*
  57  * rb_dictionary_create_named() creates a new dictionary tree which has a name.
  58  * name is the name, compare_cb is the comparator.
  59  */
  60 extern rb_dictionary *rb_dictionary_create(const char *name, DCF compare_cb);
  61
  62 /*
  63  * rb_dictionary_set_comparator_func() resets the comparator used for lookups and
  64  * insertions in the DTree structure.
  65  */
  66 extern void rb_dictionary_set_comparator_func(rb_dictionary *dict,
  67         DCF compare_cb);
  68
  69 /*
  70  * rb_dictionary_get_comparator_func() returns the comparator used for lookups and
  71  * insertions in the DTree structure.
  72  */
  73 extern DCF rb_dictionary_get_comparator_func(rb_dictionary *dict);
  74
  75 /*
  76  * rb_dictionary_get_linear_index() returns the linear index of an object in the
  77  * DTree structure.
  78  */
  79 extern int rb_dictionary_get_linear_index(rb_dictionary *dict, const void *key);
  80
  81 /*
  82  * rb_dictionary_destroy() destroys all entries in a dtree, and also optionally calls
  83  * a defined callback function to destroy any data attached to it.
  84  */
  85 extern void rb_dictionary_destroy(rb_dictionary *dtree,
  86         void (*destroy_cb)(rb_dictionary_element *delem, void *privdata),
  87         void *privdata);
  88
  89 /*
  90  * rb_dictionary_foreach() iterates all entries in a dtree, and also optionally calls
  91  * a defined callback function to use any data attached to it.
  92  *
  93  * To shortcircuit iteration, return non-zero from the callback function.
  94  */
  95 extern void rb_dictionary_foreach(rb_dictionary *dtree,
  96         int (*foreach_cb)(rb_dictionary_element *delem, void *privdata),
  97         void *privdata);
  98
  99 /*
 100  * rb_dictionary_search() iterates all entries in a dtree, and also optionally calls
 101  * a defined callback function to use any data attached to it.
 102  *
 103  * When the object is found, a non-NULL is returned from the callback, which results
 104  * in that object being returned to the user.
 105  */
 106 extern void *rb_dictionary_search(rb_dictionary *dtree,
 107         void *(*foreach_cb)(rb_dictionary_element *delem, void *privdata),
 108         void *privdata);
 109
 110 /*
 111  * rb_dictionary_foreach_start() begins an iteration over all items
 112  * keeping state in the given struct. If there is only one iteration
 113  * in progress at a time, it is permitted to remove the current element
 114  * of the iteration (but not any other element).
 115  */
 116 extern void rb_dictionary_foreach_start(rb_dictionary *dtree,
 117         rb_dictionary_iter *state);
 118
 119 /*
 120  * rb_dictionary_foreach_cur() returns the current element of the iteration,
 121  * or NULL if there are no more elements.
 122  */
 123 extern void *rb_dictionary_foreach_cur(rb_dictionary *dtree,
 124         rb_dictionary_iter *state);
 125
 126 /*
 127  * rb_dictionary_foreach_next() moves to the next element.
 128  */
 129 extern void rb_dictionary_foreach_next(rb_dictionary *dtree,
 130         rb_dictionary_iter *state);
 131
 132 /*
 133  * rb_dictionary_add() adds a key->value entry to the dictionary tree.
 134  */
 135 extern rb_dictionary_element *rb_dictionary_add(rb_dictionary *dtree, const void *key, void *data);
 136
 137 /*
 138  * rb_dictionary_find() returns a rb_dictionary_element container from a dtree for key 'key'.
 139  */
 140 extern rb_dictionary_element *rb_dictionary_find(rb_dictionary *dtree, const void *key);
 141
 142 /*
 143  * rb_dictionary_find() returns data from a dtree for key 'key'.
 144  */
 145 extern void *rb_dictionary_retrieve(rb_dictionary *dtree, const void *key);
 146
 147 /*
 148  * rb_dictionary_delete() deletes a key->value entry from the dictionary tree.
 149  */
 150 extern void *rb_dictionary_delete(rb_dictionary *dtree, const void *key);
 151
 152 /*
 153  * rb_dictionary_size() returns the number of elements in a dictionary tree.
 154  */
 155 extern unsigned int rb_dictionary_size(rb_dictionary *dtree);
 156
 157 void rb_dictionary_stats(rb_dictionary *dict, void (*cb)(const char *line, void *privdata), void *privdata);
 158 void rb_dictionary_stats_walk(void (*cb)(const char *line, void *privdata), void *privdata);
 159
 160 #ifndef _WIN32
 161
 162 #define RB_POINTER_TO_INT(x)            ((int32_t) (long) (x))
 163 #define RB_INT_TO_POINTER(x)            ((void *) (long) (int32_t) (x))
 164
 165 #define RB_POINTER_TO_UINT(x)           ((uint32_t) (unsigned long) (x))
 166 #define RB_UINT_TO_POINTER(x)           ((void *) (unsigned long) (uint32_t) (x))
 167
 168 #else
 169
 170 #define RB_POINTER_TO_INT(x)            ((int32_t) (unsigned long long) (x))
 171 #define RB_INT_TO_POINTER(x)            ((void *) (unsigned long long) (int32_t) (x))
 172
 173 #define RB_POINTER_TO_UINT(x)           ((uint32_t) (unsigned long long) (x))
 174 #define RB_UINT_TO_POINTER(x)           ((void *) (unsigned long long) (uint32_t) (x))
 175
 176 #endif
 177
 178 static inline int rb_int32cmp(const void *a, const void *b)
 179 {
 180         return RB_POINTER_TO_INT(b) - RB_POINTER_TO_INT(a);
 181 }
 182
 183 static inline int rb_uint32cmp(const void *a, const void *b)
 184 {
 185         return RB_POINTER_TO_UINT(b) - RB_POINTER_TO_UINT(a);
 186 }
 187
 188 #endif