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jfr.im git - irc/evilnet/x3.git/blob - src/dict-splay.c
1 /* dict-splay.c - Abstract dictionary type
2 * Copyright 2000-2004 srvx Development Team
4 * This file is part of srvx.
6 * srvx is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
21 * Create new dictionary.
26 dict_t dict
= calloc(1, sizeof(*dict
));
31 * Return number of entries in the dictionary.
34 dict_size(dict_t dict
)
40 * Set the function to be called when freeing a key structure.
41 * If the function is NULL, just forget about the pointer.
44 dict_set_free_keys(dict_t dict
, free_f free_keys
)
46 dict
->free_keys
= free_keys
;
50 * Set the function to free data.
51 * If the function is NULL, just forget about the pointer.
54 dict_set_free_data(dict_t dict
, free_f free_data
)
56 dict
->free_data
= free_data
;
60 dict_foreach(dict_t dict
, dict_iterator_f it_f
, void *extra
)
64 for (it
=dict_first(dict
); it
; it
=iter_next(it
)) {
65 if (it_f(iter_key(it
), iter_data(it
), extra
)) return iter_key(it
);
71 * This function finds a node and pulls it to the top of the tree.
72 * This helps balance the tree and auto-cache things you search for.
74 static struct dict_node
*
75 dict_splay(struct dict_node
*node
, const char *key
)
77 struct dict_node N
, *l
, *r
, *y
;
78 if (!node
) return NULL
;
83 int res
= irccasecmp(key
, node
->key
);
87 res
= irccasecmp(key
, node
->l
->key
);
98 } else { /* res > 0 */
100 res
= irccasecmp(key
, node
->r
->key
);
121 * Free node. Free data/key using free_f functions.
124 dict_dispose_node(struct dict_node
*node
, free_f free_keys
, free_f free_data
)
126 if (free_keys
&& node
->key
)
127 free_keys((void*)node
->key
);
128 if (free_data
&& node
->data
)
129 free_data(node
->data
);
134 * Insert an entry into the dictionary.
135 * Key ordering (and uniqueness) is determined by case-insensitive
139 dict_insert(dict_t dict
, const char *key
, void *data
)
141 struct dict_node
*new_node
;
144 new_node
= malloc(sizeof(struct dict_node
));
146 new_node
->data
= data
;
149 dict
->root
= dict_splay(dict
->root
, key
);
150 res
= irccasecmp(key
, dict
->root
->key
);
152 /* insert just "before" current root */
153 new_node
->l
= dict
->root
->l
;
154 new_node
->r
= dict
->root
;
155 dict
->root
->l
= NULL
;
156 if (dict
->root
->prev
) {
157 dict
->root
->prev
->next
= new_node
;
159 dict
->first
= new_node
;
161 new_node
->prev
= dict
->root
->prev
;
162 new_node
->next
= dict
->root
;
163 dict
->root
->prev
= new_node
;
164 dict
->root
= new_node
;
165 } else if (res
> 0) {
166 /* insert just "after" current root */
167 new_node
->r
= dict
->root
->r
;
168 new_node
->l
= dict
->root
;
169 dict
->root
->r
= NULL
;
170 if (dict
->root
->next
) {
171 dict
->root
->next
->prev
= new_node
;
173 dict
->last
= new_node
;
175 new_node
->next
= dict
->root
->next
;
176 new_node
->prev
= dict
->root
;
177 dict
->root
->next
= new_node
;
178 dict
->root
= new_node
;
180 /* maybe we don't want to overwrite it .. oh well */
181 if (dict
->free_data
) dict
->free_data(dict
->root
->data
);
182 if (dict
->free_keys
) dict
->free_keys((void*)dict
->root
->key
);
184 dict
->root
->key
= key
;
185 dict
->root
->data
= data
;
186 /* decrement the count since we dropped the node */
190 new_node
->l
= new_node
->r
= NULL
;
191 new_node
->next
= new_node
->prev
= NULL
;
192 dict
->root
= dict
->first
= dict
->last
= new_node
;
198 * Remove an entry from the dictionary.
199 * Return non-zero if it was found, or zero if the key was not in the
203 dict_remove2(dict_t dict
, const char *key
, int no_dispose
)
205 struct dict_node
*new_root
, *old_root
;
209 dict
->root
= dict_splay(dict
->root
, key
);
210 if (irccasecmp(key
, dict
->root
->key
))
213 if (!dict
->root
->l
) {
214 new_root
= dict
->root
->r
;
216 new_root
= dict_splay(dict
->root
->l
, key
);
217 new_root
->r
= dict
->root
->r
;
219 if (dict
->root
->prev
) dict
->root
->prev
->next
= dict
->root
->next
;
220 if (dict
->first
== dict
->root
) dict
->first
= dict
->first
->next
;
221 if (dict
->root
->next
) dict
->root
->next
->prev
= dict
->root
->prev
;
222 if (dict
->last
== dict
->root
) dict
->last
= dict
->last
->prev
;
223 old_root
= dict
->root
;
224 dict
->root
= new_root
;
229 dict_dispose_node(old_root
, dict
->free_keys
, dict
->free_data
);
235 * Find an entry in the dictionary.
236 * If "found" is non-NULL, set it to non-zero if the key was found.
237 * Return the data associated with the key (or NULL if the key was
241 dict_find(dict_t dict
, const char *key
, int *found
)
244 if (!dict
|| !dict
->root
|| !key
) {
249 dict
->root
= dict_splay(dict
->root
, key
);
250 was_found
= !irccasecmp(key
, dict
->root
->key
);
253 return was_found
? dict
->root
->data
: NULL
;
257 * Delete an entire dictionary.
260 dict_delete(dict_t dict
)
262 dict_iterator_t it
, next
;
265 for (it
=dict_first(dict
); it
; it
=next
) {
266 next
= iter_next(it
);
267 dict_dispose_node(it
, dict
->free_keys
, dict
->free_data
);
272 struct dict_sanity_struct
{
273 unsigned int node_count
;
274 struct dict_node
*bad_node
;
279 dict_sanity_check_node(struct dict_node
*node
, struct dict_sanity_struct
*dss
)
282 snprintf(dss
->error
, sizeof(dss
->error
), "Node %p had null key", node
);
286 if (dict_sanity_check_node(node
->l
, dss
)) return 1;
287 if (irccasecmp(node
->l
->key
, node
->key
) >= 0) {
288 snprintf(dss
->error
, sizeof(dss
->error
), "Node %p's left child's key '%s' >= its key '%s'", node
, node
->l
->key
, node
->key
);
293 if (dict_sanity_check_node(node
->r
, dss
)) return 1;
294 if (irccasecmp(node
->key
, node
->r
->key
) >= 0) {
295 snprintf(dss
->error
, sizeof(dss
->error
), "Node %p's right child's key '%s' <= its key '%s'", node
, node
->r
->key
, node
->key
);
304 * Perform sanity checks on the dict's internal structure.
307 dict_sanity_check(dict_t dict
)
309 struct dict_sanity_struct dss
;
313 if (dict
->root
&& dict_sanity_check_node(dict
->root
, &dss
)) {
314 return strdup(dss
.error
);
315 } else if (dss
.node_count
!= dict
->count
) {
316 snprintf(dss
.error
, sizeof(dss
.error
), "Counted %d nodes but expected %d.", dss
.node_count
, dict
->count
);
317 return strdup(dss
.error
);