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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 x3.
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
;
80 if (!node
) return NULL
;
86 res
= irccasecmp(key
, node
->key
);
90 res
= irccasecmp(key
, node
->l
->key
);
101 } else { /* res > 0 */
103 res
= irccasecmp(key
, node
->r
->key
);
124 * Free node. Free data/key using free_f functions.
127 dict_dispose_node(struct dict_node
*node
, free_f free_keys
, free_f free_data
)
129 if (free_keys
&& node
->key
) {
130 if (free_keys
== free
)
131 free((void*)node
->key
);
133 free_keys((void*)node
->key
);
135 if (free_data
&& node
->data
) {
136 if (free_data
== free
)
139 free_data(node
->data
);
145 * Insert an entry into the dictionary.
146 * Key ordering (and uniqueness) is determined by case-insensitive
150 dict_insert(dict_t dict
, const char *key
, void *data
)
152 struct dict_node
*new_node
;
156 new_node
= malloc(sizeof(struct dict_node
));
158 new_node
->data
= data
;
161 dict
->root
= dict_splay(dict
->root
, key
);
162 res
= irccasecmp(key
, dict
->root
->key
);
164 /* insert just "before" current root */
165 new_node
->l
= dict
->root
->l
;
166 new_node
->r
= dict
->root
;
167 dict
->root
->l
= NULL
;
168 if (dict
->root
->prev
) {
169 dict
->root
->prev
->next
= new_node
;
171 dict
->first
= new_node
;
173 new_node
->prev
= dict
->root
->prev
;
174 new_node
->next
= dict
->root
;
175 dict
->root
->prev
= new_node
;
176 dict
->root
= new_node
;
177 } else if (res
> 0) {
178 /* insert just "after" current root */
179 new_node
->r
= dict
->root
->r
;
180 new_node
->l
= dict
->root
;
181 dict
->root
->r
= NULL
;
182 if (dict
->root
->next
) {
183 dict
->root
->next
->prev
= new_node
;
185 dict
->last
= new_node
;
187 new_node
->next
= dict
->root
->next
;
188 new_node
->prev
= dict
->root
;
189 dict
->root
->next
= new_node
;
190 dict
->root
= new_node
;
192 /* maybe we don't want to overwrite it .. oh well */
193 if (dict
->free_data
) {
194 if (dict
->free_data
== free
)
195 free(dict
->root
->data
);
197 dict
->free_data(dict
->root
->data
);
199 if (dict
->free_keys
) {
200 if (dict
->free_keys
== free
)
201 free((void*)dict
->root
->key
);
203 dict
->free_keys((void*)dict
->root
->key
);
206 dict
->root
->key
= key
;
207 dict
->root
->data
= data
;
208 /* decrement the count since we dropped the node */
212 new_node
->l
= new_node
->r
= NULL
;
213 new_node
->next
= new_node
->prev
= NULL
;
214 dict
->root
= dict
->first
= dict
->last
= new_node
;
220 * Remove an entry from the dictionary.
221 * Return non-zero if it was found, or zero if the key was not in the
225 dict_remove2(dict_t dict
, const char *key
, int no_dispose
)
227 struct dict_node
*new_root
, *old_root
;
232 dict
->root
= dict_splay(dict
->root
, key
);
233 if (irccasecmp(key
, dict
->root
->key
))
236 if (!dict
->root
->l
) {
237 new_root
= dict
->root
->r
;
239 new_root
= dict_splay(dict
->root
->l
, key
);
240 new_root
->r
= dict
->root
->r
;
242 if (dict
->root
->prev
) dict
->root
->prev
->next
= dict
->root
->next
;
243 if (dict
->first
== dict
->root
) dict
->first
= dict
->first
->next
;
244 if (dict
->root
->next
) dict
->root
->next
->prev
= dict
->root
->prev
;
245 if (dict
->last
== dict
->root
) dict
->last
= dict
->last
->prev
;
246 old_root
= dict
->root
;
247 dict
->root
= new_root
;
252 dict_dispose_node(old_root
, dict
->free_keys
, dict
->free_data
);
258 * Find an entry in the dictionary.
259 * If "found" is non-NULL, set it to non-zero if the key was found.
260 * Return the data associated with the key (or NULL if the key was
264 dict_find(dict_t dict
, const char *key
, int *found
)
267 if (!dict
|| !dict
->root
|| !key
) {
273 dict
->root
= dict_splay(dict
->root
, key
);
274 was_found
= !irccasecmp(key
, dict
->root
->key
);
277 return was_found
? dict
->root
->data
: NULL
;
281 * Delete an entire dictionary.
284 dict_delete(dict_t dict
)
286 dict_iterator_t it
, next
;
289 for (it
=dict_first(dict
); it
; it
=next
) {
290 next
= iter_next(it
);
291 dict_dispose_node(it
, dict
->free_keys
, dict
->free_data
);
296 struct dict_sanity_struct
{
297 unsigned int node_count
;
298 struct dict_node
*bad_node
;
303 dict_sanity_check_node(struct dict_node
*node
, struct dict_sanity_struct
*dss
)
307 snprintf(dss
->error
, sizeof(dss
->error
), "Node %p had null key", node
);
311 if (dict_sanity_check_node(node
->l
, dss
)) return 1;
312 if (irccasecmp(node
->l
->key
, node
->key
) >= 0) {
313 snprintf(dss
->error
, sizeof(dss
->error
), "Node %p's left child's key '%s' >= its key '%s'", node
, node
->l
->key
, node
->key
);
318 if (dict_sanity_check_node(node
->r
, dss
)) return 1;
319 if (irccasecmp(node
->key
, node
->r
->key
) >= 0) {
320 snprintf(dss
->error
, sizeof(dss
->error
), "Node %p's right child's key '%s' <= its key '%s'", node
, node
->r
->key
, node
->key
);
329 * Perform sanity checks on the dict's internal structure.
332 dict_sanity_check(dict_t dict
)
334 struct dict_sanity_struct dss
;
339 if (dict
->root
&& dict_sanity_check_node(dict
->root
, &dss
)) {
340 return strdup(dss
.error
);
341 } else if (dss
.node_count
!= dict
->count
) {
342 snprintf(dss
.error
, sizeof(dss
.error
), "Counted %d nodes but expected %d.", dss
.node_count
, dict
->count
);
343 return strdup(dss
.error
);