lib/libc/citrus/citrus_lookup.c

   1 /*      $NetBSD: src/lib/libc/citrus/citrus_lookup.c,v 1.3 2004/07/21 14:16:34 tshiozak Exp $   */
   2 /*      $DragonFly: src/lib/libc/citrus/citrus_lookup.c,v 1.2 2005/03/16 06:13:24 joerg 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 <assert.h>
  31 #include <stdio.h>
  32 #include <stdlib.h>
  33 #include <string.h>
  34 #include <errno.h>
  35 #include <limits.h>
  36 #include <unistd.h>
  37 #include <fcntl.h>
  38 #include <paths.h>
  39 #include <dirent.h>
  40 #include <sys/types.h>
  41
  42 #include "citrus_namespace.h"
  43 #include "citrus_bcs.h"
  44 #include "citrus_region.h"
  45 #include "citrus_memstream.h"
  46 #include "citrus_mmap.h"
  47 #include "citrus_db.h"
  48 #include "citrus_db_hash.h"
  49 #include "citrus_lookup.h"
  50 #include "citrus_lookup_file.h"
  51
  52 struct _citrus_lookup {
  53         union {
  54                 struct {
  55                         struct _citrus_db *db;
  56                         struct _citrus_region file;
  57                         int num, idx;
  58                         struct _db_locator locator;
  59                 } db;
  60                 struct {
  61                         struct _region r;
  62                         struct _memstream ms;
  63                 } plain;
  64         } u;
  65 #define cl_db           u.db.db
  66 #define cl_dbidx        u.db.idx
  67 #define cl_dbfile       u.db.file
  68 #define cl_dbnum        u.db.num
  69 #define cl_dblocator    u.db.locator
  70 #define cl_plainr       u.plain.r
  71 #define cl_plainms      u.plain.ms
  72         int cl_ignore_case;
  73         int cl_rewind;
  74         char *cl_key;
  75         size_t cl_keylen;
  76         int (*cl_next)(struct _citrus_lookup *, struct _region *,
  77                        struct _region *);
  78         int (*cl_lookup)(struct _citrus_lookup *, const char *,
  79                          struct _region *);
  80         int (*cl_num_entries)(struct _citrus_lookup *);
  81         void (*cl_close)(struct _citrus_lookup *);
  82 };
  83
  84 static int
  85 seq_get_num_entries_db(struct _citrus_lookup *cl)
  86 {
  87         return cl->cl_dbnum;
  88 }
  89
  90 static int
  91 seq_next_db(struct _citrus_lookup *cl,
  92             struct _region *key, struct _region *data)
  93 {
  94
  95         if (cl->cl_key) {
  96                 if (key)
  97                         _region_init(key, cl->cl_key, cl->cl_keylen);
  98                 return _db_lookup_by_s(cl->cl_db, cl->cl_key, data,
  99                                        &cl->cl_dblocator);
 100         }
 101
 102         if (cl->cl_rewind) {
 103                 cl->cl_dbidx = 0;
 104         }
 105         cl->cl_rewind = 0;
 106         if (cl->cl_dbidx >= cl->cl_dbnum)
 107                 return ENOENT;
 108
 109         return _db_get_entry(cl->cl_db, cl->cl_dbidx++, key, data);
 110 }
 111
 112 static int
 113 seq_lookup_db(struct _citrus_lookup *cl, const char *key,
 114               struct _region *data)
 115 {
 116         cl->cl_rewind = 0;
 117         free(cl->cl_key);
 118         cl->cl_key = strdup(key);
 119         if (cl->cl_ignore_case)
 120                 _bcs_convert_to_lower(cl->cl_key);
 121         cl->cl_keylen = strlen(cl->cl_key);
 122         _db_locator_init(&cl->cl_dblocator);
 123         return _db_lookup_by_s(cl->cl_db, cl->cl_key, data, &cl->cl_dblocator);
 124 }
 125
 126 static void
 127 seq_close_db(struct _citrus_lookup *cl)
 128 {
 129         _db_close(cl->cl_db);
 130         _unmap_file(&cl->cl_dbfile);
 131 }
 132
 133 static int
 134 seq_open_db(struct _citrus_lookup *cl, const char *name)
 135 {
 136         int ret;
 137         struct _region r;
 138         char path[PATH_MAX];
 139
 140         snprintf(path, sizeof(path), "%s.db", name);
 141         ret = _map_file(&r, path);
 142         if (ret)
 143                 return ret;
 144
 145         ret = _db_open(&cl->cl_db, &r, _CITRUS_LOOKUP_MAGIC,
 146                        _db_hash_std, NULL);
 147         if (ret) {
 148                 _unmap_file(&r);
 149                 return ret;
 150         }
 151
 152         cl->cl_dbfile = r;
 153         cl->cl_dbnum = _db_get_num_entries(cl->cl_db);
 154         cl->cl_dbidx = 0;
 155         cl->cl_rewind = 1;
 156         cl->cl_lookup = &seq_lookup_db;
 157         cl->cl_next = &seq_next_db;
 158         cl->cl_num_entries = &seq_get_num_entries_db;
 159         cl->cl_close = &seq_close_db;
 160
 161         return 0;
 162 }
 163
 164 #define T_COMM '#'
 165 static int
 166 seq_next_plain(struct _citrus_lookup *cl, struct _region *key,
 167                struct _region *data)
 168 {
 169         const char *p, *q;
 170         size_t len;
 171
 172         if (cl->cl_rewind)
 173                 _memstream_bind(&cl->cl_plainms, &cl->cl_plainr);
 174         cl->cl_rewind = 0;
 175
 176 retry:
 177         p = _memstream_getln(&cl->cl_plainms, &len);
 178         if (p == NULL)
 179                 return ENOENT;
 180         /* ignore comment */
 181         q = memchr(p, T_COMM, len);
 182         if (q) {
 183                 len = q-p;
 184         }
 185         /* ignore trailing spaces */
 186         _bcs_trunc_rws_len(p, &len);
 187         p = _bcs_skip_ws_len(p, &len);
 188         q = _bcs_skip_nonws_len(p, &len);
 189         if (p==q)
 190                 goto retry;
 191         if (cl->cl_key && ((size_t)(q-p) != cl->cl_keylen ||
 192                            memcmp(p, cl->cl_key, (size_t)(q-p)) != 0))
 193                 goto retry;
 194
 195         /* found a entry */
 196         if (key)
 197                 _region_init(key, __DECONST(char *, p), q-p);
 198         p = _bcs_skip_ws_len(q, &len);
 199         if (data)
 200                 _region_init(data, len ? __DECONST(char *, p) : NULL, len);
 201
 202         return 0;
 203 }
 204
 205 static int
 206 seq_get_num_entries_plain(struct _citrus_lookup *cl)
 207 {
 208         int num;
 209
 210         num = 0;
 211         while (seq_next_plain(cl, NULL, NULL) == 0)
 212                 num++;
 213
 214         return num;
 215 }
 216
 217 static int
 218 seq_lookup_plain(struct _citrus_lookup *cl, const char *key,
 219                  struct _region *data)
 220 {
 221         size_t len;
 222         const char *p;
 223
 224         cl->cl_rewind = 0;
 225         free(cl->cl_key);
 226         cl->cl_key = strdup(key);
 227         if (cl->cl_ignore_case)
 228                 _bcs_convert_to_lower(cl->cl_key);
 229         cl->cl_keylen = strlen(cl->cl_key);
 230         _memstream_bind(&cl->cl_plainms, &cl->cl_plainr);
 231         p = _memstream_matchline(&cl->cl_plainms, cl->cl_key, &len, 0);
 232         if (p == NULL)
 233                 return ENOENT;
 234         if (data)
 235                 _region_init(data, __DECONST(char *, p), len);
 236
 237         return 0;
 238 }
 239
 240 static void
 241 seq_close_plain(struct _citrus_lookup *cl)
 242 {
 243         _unmap_file(&cl->cl_plainr);
 244 }
 245
 246 static int
 247 seq_open_plain(struct _citrus_lookup *cl, const char *name)
 248 {
 249         int ret;
 250
 251         /* open read stream */
 252         ret = _map_file(&cl->cl_plainr, name);
 253         if (ret)
 254                 return ret;
 255
 256         cl->cl_rewind = 1;
 257         cl->cl_next = &seq_next_plain;
 258         cl->cl_lookup = &seq_lookup_plain;
 259         cl->cl_num_entries = &seq_get_num_entries_plain;
 260         cl->cl_close = &seq_close_plain;
 261
 262         return 0;
 263 }
 264
 265 int
 266 _citrus_lookup_seq_open(struct _citrus_lookup **rcl, const char *name,
 267                         int ignore_case)
 268 {
 269         int ret;
 270         struct _citrus_lookup *cl;
 271
 272         cl = malloc(sizeof(*cl));
 273         if (cl == NULL)
 274                 return errno;
 275
 276         cl->cl_key = NULL;
 277         cl->cl_keylen = 0;
 278         cl->cl_ignore_case = ignore_case;
 279         ret = seq_open_db(cl, name);
 280         if (ret == ENOENT)
 281                 ret = seq_open_plain(cl, name);
 282         if (!ret)
 283                 *rcl = cl;
 284         else
 285                 free(cl);
 286
 287         return ret;
 288 }
 289
 290 void
 291 _citrus_lookup_seq_rewind(struct _citrus_lookup *cl)
 292 {
 293         cl->cl_rewind = 1;
 294         free(cl->cl_key);
 295         cl->cl_key = NULL;
 296         cl->cl_keylen = 0;
 297 }
 298
 299 int
 300 _citrus_lookup_seq_next(struct _citrus_lookup *cl,
 301                         struct _region *key, struct _region *data)
 302 {
 303         return (*cl->cl_next)(cl, key, data);
 304 }
 305
 306 int
 307 _citrus_lookup_seq_lookup(struct _citrus_lookup *cl, const char *key,
 308                           struct _region *data)
 309 {
 310         return (*cl->cl_lookup)(cl, key, data);
 311 }
 312
 313 int
 314 _citrus_lookup_get_number_of_entries(struct _citrus_lookup *cl)
 315 {
 316         return (*cl->cl_num_entries)(cl);
 317 }
 318
 319 void
 320 _citrus_lookup_seq_close(struct _citrus_lookup *cl)
 321 {
 322         free(cl->cl_key);
 323         (*cl->cl_close)(cl);
 324 }
 325
 326 char *
 327 _citrus_lookup_simple(const char *name, const char *key,
 328                       char *linebuf, size_t linebufsize, int ignore_case)
 329 {
 330         int ret;
 331         struct _citrus_lookup *cl;
 332         struct _region data;
 333
 334         ret = _citrus_lookup_seq_open(&cl, name, ignore_case);
 335         if (ret)
 336                 return NULL;
 337
 338         ret = _citrus_lookup_seq_lookup(cl, key, &data);
 339         if (ret) {
 340                 _citrus_lookup_seq_close(cl);
 341                 return NULL;
 342         }
 343
 344         snprintf(linebuf, linebufsize, "%.*s",
 345                  (int)_region_size(&data), (const char *)_region_head(&data));
 346
 347         _citrus_lookup_seq_close(cl);
 348
 349         return linebuf;
 350 }