citrus_db.c revision 1.2
1 /* $NetBSD: citrus_db.c,v 1.2 2003/07/16 08:13:51 tshiozak Exp $ */ 2 3 /*- 4 * Copyright (c)2003 Citrus Project, 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 #if defined(LIBC_SCCS) && !defined(lint) 31 __RCSID("$NetBSD: citrus_db.c,v 1.2 2003/07/16 08:13:51 tshiozak Exp $"); 32 #endif /* LIBC_SCCS and not lint */ 33 34 #include "namespace.h" 35 #include <assert.h> 36 #include <stdio.h> 37 #include <stdlib.h> 38 #include <string.h> 39 #include <errno.h> 40 #include <limits.h> 41 #include <sys/types.h> 42 43 #include "citrus_namespace.h" 44 #include "citrus_bcs.h" 45 #include "citrus_region.h" 46 #include "citrus_memstream.h" 47 #include "citrus_mmap.h" 48 #include "citrus_db.h" 49 #include "citrus_db_file.h" 50 51 struct _citrus_db { 52 /* private */ 53 struct _region db_region; 54 u_int32_t (*db_hashfunc)(void *, struct _citrus_region *); 55 void *db_hashfunc_closure; 56 }; 57 58 int 59 _citrus_db_open(struct _citrus_db **rdb, struct _region *r, const char *magic, 60 u_int32_t (*hashfunc)(void *, struct _citrus_region *), 61 void *hashfunc_closure) 62 { 63 struct _memstream ms; 64 struct _citrus_db *db; 65 struct _citrus_db_header_x *dhx; 66 67 _memstream_bind(&ms, r); 68 69 /* sanity check */ 70 dhx = _memstream_getregion(&ms, NULL, sizeof(*dhx)); 71 if (dhx == NULL) 72 return EFTYPE; 73 if (strncmp(dhx->dhx_magic, magic, _CITRUS_DB_MAGIC_SIZE) != 0) 74 return EFTYPE; 75 if (_memstream_seek(&ms, be32toh(dhx->dhx_entry_offset), SEEK_SET)) 76 return EFTYPE; 77 78 if (be32toh(dhx->dhx_num_entries)*_CITRUS_DB_ENTRY_SIZE > 79 _memstream_remainder(&ms)) 80 return EFTYPE; 81 82 db = malloc(sizeof(*db)); 83 if (db==NULL) 84 return errno; 85 db->db_region = *r; 86 db->db_hashfunc = hashfunc; 87 db->db_hashfunc_closure = hashfunc_closure; 88 *rdb = db; 89 90 return 0; 91 } 92 93 void 94 _citrus_db_close(struct _citrus_db *db) 95 { 96 free(db); 97 } 98 99 int 100 _citrus_db_lookup(struct _citrus_db *db, struct _citrus_region *key, 101 struct _citrus_region *data, struct _citrus_db_locator *dl) 102 { 103 u_int32_t hashval, num_entries; 104 size_t offset; 105 struct _memstream ms; 106 struct _citrus_db_header_x *dhx; 107 struct _citrus_db_entry_x *dex; 108 struct _citrus_region r; 109 110 _memstream_bind(&ms, &db->db_region); 111 112 dhx = _memstream_getregion(&ms, NULL, sizeof(*dhx)); 113 _DIAGASSERT(dhx); 114 num_entries = be32toh(dhx->dhx_num_entries); 115 if (num_entries == 0) 116 return ENOENT; 117 118 if (dl != NULL && dl->dl_offset>0) { 119 hashval = dl->dl_hashval; 120 offset = dl->dl_offset; 121 if (offset >= _region_size(&db->db_region)) 122 return ENOENT; 123 } else { 124 hashval = 125 db->db_hashfunc(db->db_hashfunc_closure, key)%num_entries; 126 offset = 127 be32toh(dhx->dhx_entry_offset) + 128 hashval * _CITRUS_DB_ENTRY_SIZE; 129 if (dl) 130 dl->dl_hashval = hashval; 131 } 132 do { 133 /* seek to the next entry */ 134 if (_citrus_memory_stream_seek(&ms, offset, SEEK_SET)) 135 return EFTYPE; 136 /* get the entry record */ 137 dex = _memstream_getregion(&ms, NULL, _CITRUS_DB_ENTRY_SIZE); 138 if (dex == NULL) 139 return EFTYPE; 140 141 /* jump to next entry having the same hash value. */ 142 offset = be32toh(dex->dex_next_offset); 143 144 /* save the current position */ 145 if (dl) { 146 dl->dl_offset = offset; 147 if (offset==0) 148 dl->dl_offset = _region_size(&db->db_region); 149 } 150 151 /* compare hash value. */ 152 if (be32toh(dex->dex_hash_value) != hashval) 153 /* not found */ 154 break; 155 /* compare key length */ 156 if (be32toh(dex->dex_key_size) == _region_size(key)) { 157 /* seek to the head of the key. */ 158 if (_memstream_seek(&ms, be32toh(dex->dex_key_offset), 159 SEEK_SET)) 160 return EFTYPE; 161 /* get the region of the key */ 162 if (_memstream_getregion(&ms, &r, 163 _region_size(key)) == NULL) 164 return EFTYPE; 165 /* compare key byte stream */ 166 if (memcmp(_region_head(&r), _region_head(key), 167 _region_size(key)) == 0) { 168 /* match */ 169 if (_memstream_seek( 170 &ms, be32toh(dex->dex_data_offset), 171 SEEK_SET)) 172 return EFTYPE; 173 if (_memstream_getregion( 174 &ms, data, 175 be32toh(dex->dex_data_size)) == NULL) 176 return EFTYPE; 177 return 0; 178 } 179 } 180 } while (offset != 0); 181 182 return ENOENT; 183 } 184 185 int 186 _citrus_db_lookup_by_string(struct _citrus_db *db, const char *key, 187 struct _citrus_region *data, 188 struct _citrus_db_locator *dl) 189 { 190 struct _region r; 191 192 /* LINTED: discard const */ 193 _region_init(&r, (char *)key, strlen(key)); 194 195 return _citrus_db_lookup(db, &r, data, dl); 196 } 197 198 int 199 _citrus_db_lookup8_by_string(struct _citrus_db *db, const char *key, 200 u_int8_t *rval, struct _citrus_db_locator *dl) 201 { 202 int ret; 203 struct _region r; 204 205 ret = _citrus_db_lookup_by_string(db, key, &r, dl); 206 if (ret) 207 return ret; 208 209 if (_region_size(&r) != 1) 210 return EFTYPE; 211 212 if (rval) 213 memcpy(rval, _region_head(&r), 1); 214 215 return 0; 216 } 217 218 int 219 _citrus_db_lookup16_by_string(struct _citrus_db *db, const char *key, 220 u_int16_t *rval, struct _citrus_db_locator *dl) 221 { 222 int ret; 223 struct _region r; 224 u_int16_t val; 225 226 ret = _citrus_db_lookup_by_string(db, key, &r, dl); 227 if (ret) 228 return ret; 229 230 if (_region_size(&r) != 2) 231 return EFTYPE; 232 233 if (rval) { 234 memcpy(&val, _region_head(&r), 2); 235 *rval = be16toh(val); 236 } 237 238 return 0; 239 } 240 241 int 242 _citrus_db_lookup32_by_string(struct _citrus_db *db, const char *key, 243 u_int32_t *rval, struct _citrus_db_locator *dl) 244 { 245 int ret; 246 struct _region r; 247 u_int32_t val; 248 249 ret = _citrus_db_lookup_by_string(db, key, &r, dl); 250 if (ret) 251 return ret; 252 253 if (_region_size(&r) != 4) 254 return EFTYPE; 255 256 if (rval) { 257 memcpy(&val, _region_head(&r), 4); 258 *rval = be32toh(val); 259 } 260 261 return 0; 262 } 263 264 int 265 _citrus_db_lookup_string_by_string(struct _citrus_db *db, const char *key, 266 const char **rdata, 267 struct _citrus_db_locator *dl) 268 { 269 int ret; 270 struct _region r; 271 272 ret = _citrus_db_lookup_by_string(db, key, &r, dl); 273 if (ret) 274 return ret; 275 276 /* check whether the string is null terminated */ 277 if (_region_size(&r) == 0) 278 return EFTYPE; 279 if (*((const char*)_region_head(&r)+_region_size(&r)-1) != '\0') 280 return EFTYPE; 281 282 if (rdata) 283 *rdata = _region_head(&r); 284 285 return 0; 286 } 287 288 int 289 _citrus_db_get_number_of_entries(struct _citrus_db *db) 290 { 291 struct _memstream ms; 292 struct _citrus_db_header_x *dhx; 293 294 _memstream_bind(&ms, &db->db_region); 295 296 dhx = _memstream_getregion(&ms, NULL, sizeof(*dhx)); 297 _DIAGASSERT(dhx); 298 return (int)be32toh(dhx->dhx_num_entries); 299 } 300 301 int 302 _citrus_db_get_entry(struct _citrus_db *db, int idx, 303 struct _region *key, struct _region *data) 304 { 305 u_int32_t num_entries; 306 size_t offset; 307 struct _memstream ms; 308 struct _citrus_db_header_x *dhx; 309 struct _citrus_db_entry_x *dex; 310 311 _memstream_bind(&ms, &db->db_region); 312 313 dhx = _memstream_getregion(&ms, NULL, sizeof(*dhx)); 314 _DIAGASSERT(dhx); 315 num_entries = be32toh(dhx->dhx_num_entries); 316 if (idx<0 || (u_int32_t)idx>=num_entries) 317 return EINVAL; 318 319 /* seek to the next entry */ 320 offset = be32toh(dhx->dhx_entry_offset) + idx * _CITRUS_DB_ENTRY_SIZE; 321 if (_citrus_memory_stream_seek(&ms, offset, SEEK_SET)) 322 return EFTYPE; 323 /* get the entry record */ 324 dex = _memstream_getregion(&ms, NULL, _CITRUS_DB_ENTRY_SIZE); 325 if (dex == NULL) 326 return EFTYPE; 327 /* seek to the head of the key. */ 328 if (_memstream_seek(&ms, be32toh(dex->dex_key_offset), SEEK_SET)) 329 return EFTYPE; 330 /* get the region of the key. */ 331 if (_memstream_getregion(&ms, key, be32toh(dex->dex_key_size))==NULL) 332 return EFTYPE; 333 /* seek to the head of the data. */ 334 if (_memstream_seek(&ms, be32toh(dex->dex_data_offset), SEEK_SET)) 335 return EFTYPE; 336 /* get the region of the data. */ 337 if (_memstream_getregion(&ms, data, be32toh(dex->dex_data_size))==NULL) 338 return EFTYPE; 339 340 return 0; 341 } 342
Indexes created Fri Sep 26 08:10:20 GMT 2025