lib/libc/citrus/citrus_db.c

   1 /* $FreeBSD: head/lib/libc/iconv/citrus_db.c 219019 2011-02-25 00:04:39Z gabor $ */
   2 /* $NetBSD: citrus_db.c,v 1.5 2008/02/09 14:56:20 junyoung Exp $ */
   3
   4 /*-
   5  * Copyright (c)2003 Citrus Project,
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29
  30 #include <sys/cdefs.h>
  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
  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
  91 _citrus_db_close(struct _citrus_db *db)
  92 {
  93
  94         free(db);
  95 }
  96
  97 int
  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
 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
 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
 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
 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
 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
 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
 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 }