1 /* $NetBSD: src/lib/libc/citrus/citrus_db.c,v 1.3 2004/01/02 21:49:35 itojun Exp $ */ 2 /* $DragonFly: src/lib/libc/citrus/citrus_db.c,v 1.1 2005/03/11 23:33:53 joerg Exp $ */ 3 4 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/types.h> 32 #include <sys/endian.h> 33 #include <assert.h> 34 #include <errno.h> 35 #include <limits.h> 36 #include <stdio.h> 37 #include <stdlib.h> 38 #include <string.h> 39 40 #include "citrus_namespace.h" 41 #include "citrus_bcs.h" 42 #include "citrus_region.h" 43 #include "citrus_memstream.h" 44 #include "citrus_mmap.h" 45 #include "citrus_db.h" 46 #include "citrus_db_file.h" 47 48 struct _citrus_db { 49 /* private */ 50 struct _region db_region; 51 uint32_t (*db_hashfunc)(void *, struct _citrus_region *); 52 void *db_hashfunc_closure; 53 }; 54 55 int 56 _citrus_db_open(struct _citrus_db **rdb, struct _region *r, const char *magic, 57 uint32_t (*hashfunc)(void *, struct _citrus_region *), 58 void *hashfunc_closure) 59 { 60 struct _memstream ms; 61 struct _citrus_db *db; 62 struct _citrus_db_header_x *dhx; 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 91 _citrus_db_close(struct _citrus_db *db) 92 { 93 free(db); 94 } 95 96 int 97 _citrus_db_lookup(struct _citrus_db *db, struct _citrus_region *key, 98 struct _citrus_region *data, struct _citrus_db_locator *dl) 99 { 100 uint32_t hashval, num_entries; 101 size_t offset; 102 struct _memstream ms; 103 struct _citrus_db_header_x *dhx; 104 struct _citrus_db_entry_x *dex; 105 struct _citrus_region r; 106 107 _memstream_bind(&ms, &db->db_region); 108 109 dhx = _memstream_getregion(&ms, NULL, sizeof(*dhx)); 110 _DIAGASSERT(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 = 122 db->db_hashfunc(db->db_hashfunc_closure, key)%num_entries; 123 offset = 124 be32toh(dhx->dhx_entry_offset) + 125 hashval * _CITRUS_DB_ENTRY_SIZE; 126 if (dl) 127 dl->dl_hashval = hashval; 128 } 129 do { 130 /* seek to the next entry */ 131 if (_citrus_memory_stream_seek(&ms, offset, SEEK_SET)) 132 return EFTYPE; 133 /* get the entry record */ 134 dex = _memstream_getregion(&ms, NULL, _CITRUS_DB_ENTRY_SIZE); 135 if (dex == NULL) 136 return EFTYPE; 137 138 /* jump to next entry having the same hash value. */ 139 offset = be32toh(dex->dex_next_offset); 140 141 /* save the current position */ 142 if (dl) { 143 dl->dl_offset = offset; 144 if (offset==0) 145 dl->dl_offset = _region_size(&db->db_region); 146 } 147 148 /* compare hash value. */ 149 if (be32toh(dex->dex_hash_value) != hashval) 150 /* not found */ 151 break; 152 /* compare key length */ 153 if (be32toh(dex->dex_key_size) == _region_size(key)) { 154 /* seek to the head of the key. */ 155 if (_memstream_seek(&ms, be32toh(dex->dex_key_offset), 156 SEEK_SET)) 157 return EFTYPE; 158 /* get the region of the key */ 159 if (_memstream_getregion(&ms, &r, 160 _region_size(key)) == NULL) 161 return EFTYPE; 162 /* compare key byte stream */ 163 if (memcmp(_region_head(&r), _region_head(key), 164 _region_size(key)) == 0) { 165 /* match */ 166 if (_memstream_seek( 167 &ms, be32toh(dex->dex_data_offset), 168 SEEK_SET)) 169 return EFTYPE; 170 if (_memstream_getregion( 171 &ms, data, 172 be32toh(dex->dex_data_size)) == NULL) 173 return EFTYPE; 174 return 0; 175 } 176 } 177 } while (offset != 0); 178 179 return ENOENT; 180 } 181 182 int 183 _citrus_db_lookup_by_string(struct _citrus_db *db, const char *key, 184 struct _citrus_region *data, 185 struct _citrus_db_locator *dl) 186 { 187 struct _region r; 188 189 /* LINTED: discard const */ 190 _region_init(&r, (char *)key, strlen(key)); 191 192 return _citrus_db_lookup(db, &r, data, dl); 193 } 194 195 int 196 _citrus_db_lookup8_by_string(struct _citrus_db *db, const char *key, 197 uint8_t *rval, struct _citrus_db_locator *dl) 198 { 199 int ret; 200 struct _region r; 201 202 ret = _citrus_db_lookup_by_string(db, key, &r, dl); 203 if (ret) 204 return ret; 205 206 if (_region_size(&r) != 1) 207 return EFTYPE; 208 209 if (rval) 210 memcpy(rval, _region_head(&r), 1); 211 212 return 0; 213 } 214 215 int 216 _citrus_db_lookup16_by_string(struct _citrus_db *db, const char *key, 217 uint16_t *rval, struct _citrus_db_locator *dl) 218 { 219 int ret; 220 struct _region r; 221 uint16_t val; 222 223 ret = _citrus_db_lookup_by_string(db, key, &r, dl); 224 if (ret) 225 return ret; 226 227 if (_region_size(&r) != 2) 228 return EFTYPE; 229 230 if (rval) { 231 memcpy(&val, _region_head(&r), 2); 232 *rval = be16toh(val); 233 } 234 235 return 0; 236 } 237 238 int 239 _citrus_db_lookup32_by_string(struct _citrus_db *db, const char *key, 240 uint32_t *rval, struct _citrus_db_locator *dl) 241 { 242 int ret; 243 struct _region r; 244 uint32_t val; 245 246 ret = _citrus_db_lookup_by_string(db, key, &r, dl); 247 if (ret) 248 return ret; 249 250 if (_region_size(&r) != 4) 251 return EFTYPE; 252 253 if (rval) { 254 memcpy(&val, _region_head(&r), 4); 255 *rval = be32toh(val); 256 } 257 258 return 0; 259 } 260 261 int 262 _citrus_db_lookup_string_by_string(struct _citrus_db *db, const char *key, 263 const char **rdata, 264 struct _citrus_db_locator *dl) 265 { 266 int ret; 267 struct _region r; 268 269 ret = _citrus_db_lookup_by_string(db, key, &r, dl); 270 if (ret) 271 return ret; 272 273 /* check whether the string is null terminated */ 274 if (_region_size(&r) == 0) 275 return EFTYPE; 276 if (*((const char*)_region_head(&r)+_region_size(&r)-1) != '\0') 277 return EFTYPE; 278 279 if (rdata) 280 *rdata = _region_head(&r); 281 282 return 0; 283 } 284 285 int 286 _citrus_db_get_number_of_entries(struct _citrus_db *db) 287 { 288 struct _memstream ms; 289 struct _citrus_db_header_x *dhx; 290 291 _memstream_bind(&ms, &db->db_region); 292 293 dhx = _memstream_getregion(&ms, NULL, sizeof(*dhx)); 294 _DIAGASSERT(dhx); 295 return (int)be32toh(dhx->dhx_num_entries); 296 } 297 298 int 299 _citrus_db_get_entry(struct _citrus_db *db, int idx, 300 struct _region *key, struct _region *data) 301 { 302 uint32_t num_entries; 303 size_t offset; 304 struct _memstream ms; 305 struct _citrus_db_header_x *dhx; 306 struct _citrus_db_entry_x *dex; 307 308 _memstream_bind(&ms, &db->db_region); 309 310 dhx = _memstream_getregion(&ms, NULL, sizeof(*dhx)); 311 _DIAGASSERT(dhx); 312 num_entries = be32toh(dhx->dhx_num_entries); 313 if (idx < 0 || (uint32_t)idx >= num_entries) 314 return EINVAL; 315 316 /* seek to the next entry */ 317 offset = be32toh(dhx->dhx_entry_offset) + idx * _CITRUS_DB_ENTRY_SIZE; 318 if (_citrus_memory_stream_seek(&ms, offset, SEEK_SET)) 319 return EFTYPE; 320 /* get the entry record */ 321 dex = _memstream_getregion(&ms, NULL, _CITRUS_DB_ENTRY_SIZE); 322 if (dex == NULL) 323 return EFTYPE; 324 /* seek to the head of the key. */ 325 if (_memstream_seek(&ms, be32toh(dex->dex_key_offset), SEEK_SET)) 326 return EFTYPE; 327 /* get the region of the key. */ 328 if (_memstream_getregion(&ms, key, be32toh(dex->dex_key_size))==NULL) 329 return EFTYPE; 330 /* seek to the head of the data. */ 331 if (_memstream_seek(&ms, be32toh(dex->dex_data_offset), SEEK_SET)) 332 return EFTYPE; 333 /* get the region of the data. */ 334 if (_memstream_getregion(&ms, data, be32toh(dex->dex_data_size))==NULL) 335 return EFTYPE; 336 337 return 0; 338 } 339