1 /* $NetBSD: citrus_db.c,v 1.5 2008/02/09 14:56:20 junyoung Exp $ */
2
3 /*-
4 * SPDX-License-Identifier: BSD-2-Clause
5 *
6 * Copyright (c)2003 Citrus Project,
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 */
30
31 #include <sys/endian.h>
32 #include <sys/types.h>
33
34 #include <assert.h>
35 #include <errno.h>
36 #include <limits.h>
37 #include <stdio.h>
38 #include <stdlib.h>
39 #include <string.h>
40
41 #include "citrus_namespace.h"
42 #include "citrus_bcs.h"
43 #include "citrus_region.h"
44 #include "citrus_memstream.h"
45 #include "citrus_mmap.h"
46 #include "citrus_db.h"
47 #include "citrus_db_factory.h"
48 #include "citrus_db_file.h"
49
50 struct _citrus_db {
51 struct _region db_region;
52 _citrus_db_hash_func_t db_hashfunc;
53 void *db_hashfunc_closure;
54 };
55
56 int
_citrus_db_open(struct _citrus_db ** rdb,struct _region * r,const char * magic,_citrus_db_hash_func_t hashfunc,void * hashfunc_closure)57 _citrus_db_open(struct _citrus_db **rdb, struct _region *r, const char *magic,
58 _citrus_db_hash_func_t hashfunc, void *hashfunc_closure)
59 {
60 struct _citrus_db *db;
61 struct _citrus_db_header_x *dhx;
62 struct _memstream ms;
63
64 _memstream_bind(&ms, r);
65
66 /* sanity check */
67 dhx = _memstream_getregion(&ms, NULL, sizeof(*dhx));
68 if (dhx == NULL)
69 return (EFTYPE);
70 if (strncmp(dhx->dhx_magic, magic, _CITRUS_DB_MAGIC_SIZE) != 0)
71 return (EFTYPE);
72 if (_memstream_seek(&ms, be32toh(dhx->dhx_entry_offset), SEEK_SET))
73 return (EFTYPE);
74
75 if (be32toh(dhx->dhx_num_entries)*_CITRUS_DB_ENTRY_SIZE >
76 _memstream_remainder(&ms))
77 return (EFTYPE);
78
79 db = malloc(sizeof(*db));
80 if (db == NULL)
81 return (errno);
82 db->db_region = *r;
83 db->db_hashfunc = hashfunc;
84 db->db_hashfunc_closure = hashfunc_closure;
85 *rdb = db;
86
87 return (0);
88 }
89
90 void
_citrus_db_close(struct _citrus_db * db)91 _citrus_db_close(struct _citrus_db *db)
92 {
93
94 free(db);
95 }
96
97 int
_citrus_db_lookup(struct _citrus_db * db,struct _citrus_region * key,struct _citrus_region * data,struct _citrus_db_locator * dl)98 _citrus_db_lookup(struct _citrus_db *db, struct _citrus_region *key,
99 struct _citrus_region *data, struct _citrus_db_locator *dl)
100 {
101 struct _citrus_db_entry_x *dex;
102 struct _citrus_db_header_x *dhx;
103 struct _citrus_region r;
104 struct _memstream ms;
105 uint32_t hashval, num_entries;
106 size_t offset;
107
108 _memstream_bind(&ms, &db->db_region);
109
110 dhx = _memstream_getregion(&ms, NULL, sizeof(*dhx));
111 num_entries = be32toh(dhx->dhx_num_entries);
112 if (num_entries == 0)
113 return (ENOENT);
114
115 if (dl != NULL && dl->dl_offset>0) {
116 hashval = dl->dl_hashval;
117 offset = dl->dl_offset;
118 if (offset >= _region_size(&db->db_region))
119 return (ENOENT);
120 } else {
121 hashval = db->db_hashfunc(key)%num_entries;
122 offset = be32toh(dhx->dhx_entry_offset) +
123 hashval * _CITRUS_DB_ENTRY_SIZE;
124 if (dl)
125 dl->dl_hashval = hashval;
126 }
127 do {
128 /* seek to the next entry */
129 if (_citrus_memory_stream_seek(&ms, offset, SEEK_SET))
130 return (EFTYPE);
131 /* get the entry record */
132 dex = _memstream_getregion(&ms, NULL, _CITRUS_DB_ENTRY_SIZE);
133 if (dex == NULL)
134 return (EFTYPE);
135
136 /* jump to next entry having the same hash value. */
137 offset = be32toh(dex->dex_next_offset);
138
139 /* save the current position */
140 if (dl) {
141 dl->dl_offset = offset;
142 if (offset == 0)
143 dl->dl_offset = _region_size(&db->db_region);
144 }
145
146 /* compare hash value. */
147 if (be32toh(dex->dex_hash_value) != hashval)
148 /* not found */
149 break;
150 /* compare key length */
151 if (be32toh(dex->dex_key_size) == _region_size(key)) {
152 /* seek to the head of the key. */
153 if (_memstream_seek(&ms, be32toh(dex->dex_key_offset),
154 SEEK_SET))
155 return (EFTYPE);
156 /* get the region of the key */
157 if (_memstream_getregion(&ms, &r,
158 _region_size(key)) == NULL)
159 return (EFTYPE);
160 /* compare key byte stream */
161 if (memcmp(_region_head(&r), _region_head(key),
162 _region_size(key)) == 0) {
163 /* match */
164 if (_memstream_seek(
165 &ms, be32toh(dex->dex_data_offset),
166 SEEK_SET))
167 return (EFTYPE);
168 if (_memstream_getregion(
169 &ms, data,
170 be32toh(dex->dex_data_size)) == NULL)
171 return (EFTYPE);
172 return (0);
173 }
174 }
175 } while (offset != 0);
176
177 return (ENOENT);
178 }
179
180 int
_citrus_db_lookup_by_string(struct _citrus_db * db,const char * key,struct _citrus_region * data,struct _citrus_db_locator * dl)181 _citrus_db_lookup_by_string(struct _citrus_db *db, const char *key,
182 struct _citrus_region *data, struct _citrus_db_locator *dl)
183 {
184 struct _region r;
185
186 _region_init(&r, __DECONST(void *, key), strlen(key));
187
188 return (_citrus_db_lookup(db, &r, data, dl));
189 }
190
191 int
_citrus_db_lookup8_by_string(struct _citrus_db * db,const char * key,uint8_t * rval,struct _citrus_db_locator * dl)192 _citrus_db_lookup8_by_string(struct _citrus_db *db, const char *key,
193 uint8_t *rval, struct _citrus_db_locator *dl)
194 {
195 struct _region r;
196 int ret;
197
198 ret = _citrus_db_lookup_by_string(db, key, &r, dl);
199 if (ret)
200 return (ret);
201
202 if (_region_size(&r) != 1)
203 return (EFTYPE);
204
205 if (rval)
206 memcpy(rval, _region_head(&r), 1);
207
208 return (0);
209 }
210
211 int
_citrus_db_lookup16_by_string(struct _citrus_db * db,const char * key,uint16_t * rval,struct _citrus_db_locator * dl)212 _citrus_db_lookup16_by_string(struct _citrus_db *db, const char *key,
213 uint16_t *rval, struct _citrus_db_locator *dl)
214 {
215 struct _region r;
216 int ret;
217 uint16_t val;
218
219 ret = _citrus_db_lookup_by_string(db, key, &r, dl);
220 if (ret)
221 return (ret);
222
223 if (_region_size(&r) != 2)
224 return (EFTYPE);
225
226 if (rval) {
227 memcpy(&val, _region_head(&r), 2);
228 *rval = be16toh(val);
229 }
230
231 return (0);
232 }
233
234 int
_citrus_db_lookup32_by_string(struct _citrus_db * db,const char * key,uint32_t * rval,struct _citrus_db_locator * dl)235 _citrus_db_lookup32_by_string(struct _citrus_db *db, const char *key,
236 uint32_t *rval, struct _citrus_db_locator *dl)
237 {
238 struct _region r;
239 uint32_t val;
240 int ret;
241
242 ret = _citrus_db_lookup_by_string(db, key, &r, dl);
243 if (ret)
244 return (ret);
245
246 if (_region_size(&r) != 4)
247 return (EFTYPE);
248
249 if (rval) {
250 memcpy(&val, _region_head(&r), 4);
251 *rval = be32toh(val);
252 }
253
254 return (0);
255 }
256
257 int
_citrus_db_lookup_string_by_string(struct _citrus_db * db,const char * key,const char ** rdata,struct _citrus_db_locator * dl)258 _citrus_db_lookup_string_by_string(struct _citrus_db *db, const char *key,
259 const char **rdata, struct _citrus_db_locator *dl)
260 {
261 struct _region r;
262 int ret;
263
264 ret = _citrus_db_lookup_by_string(db, key, &r, dl);
265 if (ret)
266 return (ret);
267
268 /* check whether the string is null terminated */
269 if (_region_size(&r) == 0)
270 return (EFTYPE);
271 if (*((const char*)_region_head(&r)+_region_size(&r)-1) != '\0')
272 return (EFTYPE);
273
274 if (rdata)
275 *rdata = _region_head(&r);
276
277 return (0);
278 }
279
280 int
_citrus_db_get_number_of_entries(struct _citrus_db * db)281 _citrus_db_get_number_of_entries(struct _citrus_db *db)
282 {
283 struct _citrus_db_header_x *dhx;
284 struct _memstream ms;
285
286 _memstream_bind(&ms, &db->db_region);
287
288 dhx = _memstream_getregion(&ms, NULL, sizeof(*dhx));
289 return ((int)be32toh(dhx->dhx_num_entries));
290 }
291
292 int
_citrus_db_get_entry(struct _citrus_db * db,int idx,struct _region * key,struct _region * data)293 _citrus_db_get_entry(struct _citrus_db *db, int idx, struct _region *key,
294 struct _region *data)
295 {
296 struct _citrus_db_entry_x *dex;
297 struct _citrus_db_header_x *dhx;
298 struct _memstream ms;
299 uint32_t num_entries;
300 size_t offset;
301
302 _memstream_bind(&ms, &db->db_region);
303
304 dhx = _memstream_getregion(&ms, NULL, sizeof(*dhx));
305 num_entries = be32toh(dhx->dhx_num_entries);
306 if (idx < 0 || (uint32_t)idx >= num_entries)
307 return (EINVAL);
308
309 /* seek to the next entry */
310 offset = be32toh(dhx->dhx_entry_offset) + idx * _CITRUS_DB_ENTRY_SIZE;
311 if (_citrus_memory_stream_seek(&ms, offset, SEEK_SET))
312 return (EFTYPE);
313 /* get the entry record */
314 dex = _memstream_getregion(&ms, NULL, _CITRUS_DB_ENTRY_SIZE);
315 if (dex == NULL)
316 return (EFTYPE);
317 /* seek to the head of the key. */
318 if (_memstream_seek(&ms, be32toh(dex->dex_key_offset), SEEK_SET))
319 return (EFTYPE);
320 /* get the region of the key. */
321 if (_memstream_getregion(&ms, key, be32toh(dex->dex_key_size))==NULL)
322 return (EFTYPE);
323 /* seek to the head of the data. */
324 if (_memstream_seek(&ms, be32toh(dex->dex_data_offset), SEEK_SET))
325 return (EFTYPE);
326 /* get the region of the data. */
327 if (_memstream_getregion(&ms, data, be32toh(dex->dex_data_size))==NULL)
328 return (EFTYPE);
329
330 return (0);
331 }
332