BIND: update vendor tree to 9.5.2-P2
[dragonfly.git] / contrib / bind / lib / isccc / symtab.c
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1/*
2 * Portions Copyright (C) 2004, 2005, 2007 Internet Systems Consortium, Inc. ("ISC")
3 * Portions Copyright (C) 2001 Internet Software Consortium.
4 *
5 * Permission to use, copy, modify, and/or distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC AND NOMINUM DISCLAIMS ALL
10 * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
11 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY
12 * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 *
17 * Portions Copyright (C) 2001 Nominum, Inc.
18 *
19 * Permission to use, copy, modify, and/or distribute this software for any
20 * purpose with or without fee is hereby granted, provided that the above
21 * copyright notice and this permission notice appear in all copies.
22 *
23 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC AND NOMINUM DISCLAIMS ALL
24 * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
25 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY
26 * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
27 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
28 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
29 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
30 */
31
32/* $Id: symtab.c,v 1.11 2007/09/13 04:45:18 each Exp $ */
33
34/*! \file */
35
36#include <config.h>
37
38#include <ctype.h>
39#include <stdlib.h>
40
41#include <isc/assertions.h>
42#include <isc/magic.h>
43#include <isc/string.h>
44
45#include <isccc/result.h>
46#include <isccc/symtab.h>
47#include <isccc/util.h>
48
49typedef struct elt {
50 char * key;
51 unsigned int type;
52 isccc_symvalue_t value;
53 ISC_LINK(struct elt) link;
54} elt_t;
55
56typedef ISC_LIST(elt_t) eltlist_t;
57
58#define SYMTAB_MAGIC ISC_MAGIC('S', 'y', 'm', 'T')
59#define VALID_SYMTAB(st) ISC_MAGIC_VALID(st, SYMTAB_MAGIC)
60
61struct isccc_symtab {
62 unsigned int magic;
63 unsigned int size;
64 eltlist_t * table;
65 isccc_symtabundefaction_t undefine_action;
66 void * undefine_arg;
67 isc_boolean_t case_sensitive;
68};
69
70isc_result_t
71isccc_symtab_create(unsigned int size,
72 isccc_symtabundefaction_t undefine_action,
73 void *undefine_arg,
74 isc_boolean_t case_sensitive,
75 isccc_symtab_t **symtabp)
76{
77 isccc_symtab_t *symtab;
78 unsigned int i;
79
80 REQUIRE(symtabp != NULL && *symtabp == NULL);
81 REQUIRE(size > 0); /* Should be prime. */
82
83 symtab = malloc(sizeof(*symtab));
84 if (symtab == NULL)
85 return (ISC_R_NOMEMORY);
86 symtab->table = malloc(size * sizeof(eltlist_t));
87 if (symtab->table == NULL) {
88 free(symtab);
89 return (ISC_R_NOMEMORY);
90 }
91 for (i = 0; i < size; i++)
92 ISC_LIST_INIT(symtab->table[i]);
93 symtab->size = size;
94 symtab->undefine_action = undefine_action;
95 symtab->undefine_arg = undefine_arg;
96 symtab->case_sensitive = case_sensitive;
97 symtab->magic = SYMTAB_MAGIC;
98
99 *symtabp = symtab;
100
101 return (ISC_R_SUCCESS);
102}
103
104static inline void
105free_elt(isccc_symtab_t *symtab, unsigned int bucket, elt_t *elt) {
106 ISC_LIST_UNLINK(symtab->table[bucket], elt, link);
107 if (symtab->undefine_action != NULL)
108 (symtab->undefine_action)(elt->key, elt->type, elt->value,
109 symtab->undefine_arg);
110 free(elt);
111}
112
113void
114isccc_symtab_destroy(isccc_symtab_t **symtabp) {
115 isccc_symtab_t *symtab;
116 unsigned int i;
117 elt_t *elt, *nelt;
118
119 REQUIRE(symtabp != NULL);
120 symtab = *symtabp;
121 REQUIRE(VALID_SYMTAB(symtab));
122
123 for (i = 0; i < symtab->size; i++) {
124 for (elt = ISC_LIST_HEAD(symtab->table[i]);
125 elt != NULL;
126 elt = nelt) {
127 nelt = ISC_LIST_NEXT(elt, link);
128 free_elt(symtab, i, elt);
129 }
130 }
131 free(symtab->table);
132 symtab->magic = 0;
133 free(symtab);
134
135 *symtabp = NULL;
136}
137
138static inline unsigned int
139hash(const char *key, isc_boolean_t case_sensitive) {
140 const char *s;
141 unsigned int h = 0;
142 unsigned int g;
143 int c;
144
145 /*
146 * P. J. Weinberger's hash function, adapted from p. 436 of
147 * _Compilers: Principles, Techniques, and Tools_, Aho, Sethi
148 * and Ullman, Addison-Wesley, 1986, ISBN 0-201-10088-6.
149 */
150
151 if (case_sensitive) {
152 for (s = key; *s != '\0'; s++) {
153 h = ( h << 4 ) + *s;
154 if ((g = ( h & 0xf0000000 )) != 0) {
155 h = h ^ (g >> 24);
156 h = h ^ g;
157 }
158 }
159 } else {
160 for (s = key; *s != '\0'; s++) {
161 c = *s;
162 c = tolower((unsigned char)c);
163 h = ( h << 4 ) + c;
164 if ((g = ( h & 0xf0000000 )) != 0) {
165 h = h ^ (g >> 24);
166 h = h ^ g;
167 }
168 }
169 }
170
171 return (h);
172}
173
174#define FIND(s, k, t, b, e) \
175 b = hash((k), (s)->case_sensitive) % (s)->size; \
176 if ((s)->case_sensitive) { \
177 for (e = ISC_LIST_HEAD((s)->table[b]); \
178 e != NULL; \
179 e = ISC_LIST_NEXT(e, link)) { \
180 if (((t) == 0 || e->type == (t)) && \
181 strcmp(e->key, (k)) == 0) \
182 break; \
183 } \
184 } else { \
185 for (e = ISC_LIST_HEAD((s)->table[b]); \
186 e != NULL; \
187 e = ISC_LIST_NEXT(e, link)) { \
188 if (((t) == 0 || e->type == (t)) && \
189 strcasecmp(e->key, (k)) == 0) \
190 break; \
191 } \
192 }
193
194isc_result_t
195isccc_symtab_lookup(isccc_symtab_t *symtab, const char *key, unsigned int type,
196 isccc_symvalue_t *value)
197{
198 unsigned int bucket;
199 elt_t *elt;
200
201 REQUIRE(VALID_SYMTAB(symtab));
202 REQUIRE(key != NULL);
203
204 FIND(symtab, key, type, bucket, elt);
205
206 if (elt == NULL)
207 return (ISC_R_NOTFOUND);
208
209 if (value != NULL)
210 *value = elt->value;
211
212 return (ISC_R_SUCCESS);
213}
214
215isc_result_t
216isccc_symtab_define(isccc_symtab_t *symtab, char *key, unsigned int type,
217 isccc_symvalue_t value, isccc_symexists_t exists_policy)
218{
219 unsigned int bucket;
220 elt_t *elt;
221
222 REQUIRE(VALID_SYMTAB(symtab));
223 REQUIRE(key != NULL);
224 REQUIRE(type != 0);
225
226 FIND(symtab, key, type, bucket, elt);
227
228 if (exists_policy != isccc_symexists_add && elt != NULL) {
229 if (exists_policy == isccc_symexists_reject)
230 return (ISC_R_EXISTS);
231 INSIST(exists_policy == isccc_symexists_replace);
232 ISC_LIST_UNLINK(symtab->table[bucket], elt, link);
233 if (symtab->undefine_action != NULL)
234 (symtab->undefine_action)(elt->key, elt->type,
235 elt->value,
236 symtab->undefine_arg);
237 } else {
238 elt = malloc(sizeof(*elt));
239 if (elt == NULL)
240 return (ISC_R_NOMEMORY);
241 ISC_LINK_INIT(elt, link);
242 }
243
244 elt->key = key;
245 elt->type = type;
246 elt->value = value;
247
248 /*
249 * We prepend so that the most recent definition will be found.
250 */
251 ISC_LIST_PREPEND(symtab->table[bucket], elt, link);
252
253 return (ISC_R_SUCCESS);
254}
255
256isc_result_t
257isccc_symtab_undefine(isccc_symtab_t *symtab, const char *key, unsigned int type) {
258 unsigned int bucket;
259 elt_t *elt;
260
261 REQUIRE(VALID_SYMTAB(symtab));
262 REQUIRE(key != NULL);
263
264 FIND(symtab, key, type, bucket, elt);
265
266 if (elt == NULL)
267 return (ISC_R_NOTFOUND);
268
269 free_elt(symtab, bucket, elt);
270
271 return (ISC_R_SUCCESS);
272}
273
274void
275isccc_symtab_foreach(isccc_symtab_t *symtab, isccc_symtabforeachaction_t action,
276 void *arg)
277{
278 unsigned int i;
279 elt_t *elt, *nelt;
280
281 REQUIRE(VALID_SYMTAB(symtab));
282 REQUIRE(action != NULL);
283
284 for (i = 0; i < symtab->size; i++) {
285 for (elt = ISC_LIST_HEAD(symtab->table[i]);
286 elt != NULL;
287 elt = nelt) {
288 nelt = ISC_LIST_NEXT(elt, link);
289 if ((action)(elt->key, elt->type, elt->value, arg))
290 free_elt(symtab, i, elt);
291 }
292 }
293}