include/irc_dictionary.h

   1 /*
   2  * charybdis: an advanced ircd.
   3  * irc_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 __IRC_DICTIONARY_H__
  26 #define __IRC_DICTIONARY_H__
  27
  28 struct Dictionary; /* defined in src/dictionary.c */
  29
  30 typedef int (*DCF)(const char *a, const char *b);
  31
  32 struct DictionaryElement
  33 {
  34         struct DictionaryElement *left, *right, *prev, *next;
  35         void *data;
  36         const char *key;
  37         int position;
  38 };
  39
  40 struct DictionaryIter
  41 {
  42         struct DictionaryElement *cur, *next;
  43 };
  44
  45 /*
  46  * this is a convenience macro for inlining iteration of dictionaries.
  47  */
  48 #define DICTIONARY_FOREACH(element, state, dict) for (irc_dictionary_foreach_start((dict), (state)); (element = irc_dictionary_foreach_cur((dict), (state))); irc_dictionary_foreach_next((dict), (state)))
  49
  50 /*
  51  * irc_dictionary_create() creates a new dictionary tree.
  52  * compare_cb is the comparison function, typically strcmp, strcasecmp or
  53  * irccasecmp.
  54  */
  55 extern struct Dictionary *irc_dictionary_create(DCF compare_cb);
  56
  57 /*
  58  * irc_dictionary_create_named() creates a new dictionary tree which has a name.
  59  * name is the name, compare_cb is the comparator.
  60  */
  61 extern struct Dictionary *irc_dictionary_create_named(const char *name, DCF compare_cb);
  62
  63 /*
  64  * irc_dictionary_set_comparator_func() resets the comparator used for lookups and
  65  * insertions in the DTree structure.
  66  */
  67 extern void irc_dictionary_set_comparator_func(struct Dictionary *dict,
  68         DCF compare_cb);
  69
  70 /*
  71  * irc_dictionary_get_comparator_func() returns the comparator used for lookups and
  72  * insertions in the DTree structure.
  73  */
  74 extern DCF irc_dictionary_get_comparator_func(struct Dictionary *dict);
  75
  76 /*
  77  * irc_dictionary_get_linear_index() returns the linear index of an object in the
  78  * DTree structure.
  79  */
  80 extern int irc_dictionary_get_linear_index(struct Dictionary *dict, const char *key);
  81
  82 /*
  83  * irc_dictionary_destroy() destroys all entries in a dtree, and also optionally calls
  84  * a defined callback function to destroy any data attached to it.
  85  */
  86 extern void irc_dictionary_destroy(struct Dictionary *dtree,
  87         void (*destroy_cb)(struct DictionaryElement *delem, void *privdata),
  88         void *privdata);
  89
  90 /*
  91  * irc_dictionary_foreach() iterates all entries in a dtree, and also optionally calls
  92  * a defined callback function to use any data attached to it.
  93  *
  94  * To shortcircuit iteration, return non-zero from the callback function.
  95  */
  96 extern void irc_dictionary_foreach(struct Dictionary *dtree,
  97         int (*foreach_cb)(struct DictionaryElement *delem, void *privdata),
  98         void *privdata);
  99
 100 /*
 101  * irc_dictionary_search() iterates all entries in a dtree, and also optionally calls
 102  * a defined callback function to use any data attached to it.
 103  *
 104  * When the object is found, a non-NULL is returned from the callback, which results
 105  * in that object being returned to the user.
 106  */
 107 extern void *irc_dictionary_search(struct Dictionary *dtree,
 108         void *(*foreach_cb)(struct DictionaryElement *delem, void *privdata),
 109         void *privdata);
 110
 111 /*
 112  * irc_dictionary_foreach_start() begins an iteration over all items
 113  * keeping state in the given struct. If there is only one iteration
 114  * in progress at a time, it is permitted to remove the current element
 115  * of the iteration (but not any other element).
 116  */
 117 extern void irc_dictionary_foreach_start(struct Dictionary *dtree,
 118         struct DictionaryIter *state);
 119
 120 /*
 121  * irc_dictionary_foreach_cur() returns the current element of the iteration,
 122  * or NULL if there are no more elements.
 123  */
 124 extern void *irc_dictionary_foreach_cur(struct Dictionary *dtree,
 125         struct DictionaryIter *state);
 126
 127 /*
 128  * irc_dictionary_foreach_next() moves to the next element.
 129  */
 130 extern void irc_dictionary_foreach_next(struct Dictionary *dtree,
 131         struct DictionaryIter *state);
 132
 133 /*
 134  * irc_dictionary_add() adds a key->value entry to the dictionary tree.
 135  */
 136 extern struct DictionaryElement *irc_dictionary_add(struct Dictionary *dtree, const char *key, void *data);
 137
 138 /*
 139  * irc_dictionary_find() returns a struct DictionaryElement container from a dtree for key 'key'.
 140  */
 141 extern struct DictionaryElement *irc_dictionary_find(struct Dictionary *dtree, const char *key);
 142
 143 /*
 144  * irc_dictionary_find() returns data from a dtree for key 'key'.
 145  */
 146 extern void *irc_dictionary_retrieve(struct Dictionary *dtree, const char *key);
 147
 148 /*
 149  * irc_dictionary_delete() deletes a key->value entry from the dictionary tree.
 150  */
 151 extern void *irc_dictionary_delete(struct Dictionary *dtree, const char *key);
 152
 153 /*
 154  * irc_dictionary_size() returns the number of elements in a dictionary tree.
 155  */
 156 extern unsigned int irc_dictionary_size(struct Dictionary *dtree);
 157
 158 void irc_dictionary_stats(struct Dictionary *dict, void (*cb)(const char *line, void *privdata), void *privdata);
 159
 160 #endif