src/intl/gettext/localealias.c

   1 /* Handle aliases for locale names.
   2    Copyright (C) 1995-1999, 2000, 2001 Free Software Foundation, Inc.
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 2, or (at your option)
   7    any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program; if not, write to the Free Software Foundation,
  16    Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  17
  18 /* Tell glibc's <string.h> to provide a prototype for mempcpy().
  19    This must come before <config.h> because <config.h> may include
  20    <features.h>, and once <features.h> has been included, it's too late.  */
  21 #ifndef _GNU_SOURCE
  22 #define _GNU_SOURCE    1
  23 #endif
  24
  25 #ifdef HAVE_CONFIG_H
  26 #include "config.h"
  27 #endif
  28
  29 #include <ctype.h>
  30 #include <stdio.h>
  31 #include <sys/types.h>
  32 #include <stdlib.h>
  33 #include <string.h>
  34
  35 #include "elinks.h"
  36
  37 #include "intl/gettext/gettextP.h"
  38 #include "util/memory.h"
  39 #include "util/string.h"
  40
  41 #ifdef HAVE_FGETS_UNLOCKED
  42 #undef fgets
  43 #define fgets(buf, len, s) fgets_unlocked (buf, len, s)
  44 #endif
  45 #ifdef HAVE_FEOF_UNLOCKED
  46 #undef feof
  47 #define feof(s) feof_unlocked (s)
  48 #endif
  49
  50 struct alias_map {
  51         const unsigned char *alias;
  52         const unsigned char *value;
  53 };
  54
  55 static unsigned char *string_space;
  56 static size_t string_space_act;
  57 static size_t string_space_max;
  58 static struct alias_map *map;
  59 static size_t nmap;
  60 static size_t maxmap;
  61
  62 /* Prototypes for local functions.  */
  63 static size_t read_alias_file(const unsigned char *fname, int fname_len);
  64 static int extend_alias_table(void);
  65 static int alias_compare(const struct alias_map * map1,
  66                          const struct alias_map * map2);
  67
  68 const unsigned char *
  69 _nl_expand_alias(const unsigned char *name)
  70 {
  71         static const unsigned char *locale_alias_path = LOCALEDIR;
  72         struct alias_map *retval;
  73         const unsigned char *result = NULL;
  74         size_t added;
  75
  76         do {
  77                 struct alias_map item;
  78
  79                 item.alias = name;
  80
  81                 if (nmap > 0)
  82                         retval = (struct alias_map *) bsearch(&item, map, nmap,
  83                                                               sizeof(struct
  84                                                                      alias_map),
  85                                                               (int (*)
  86                                                                (const void *,
  87                                                                 const void *)
  88                                                               ) alias_compare);
  89                 else
  90                         retval = NULL;
  91
  92                 /* We really found an alias.  Return the value.  */
  93                 if (retval != NULL) {
  94                         result = retval->value;
  95                         break;
  96                 }
  97
  98                 /* Perhaps we can find another alias file.  */
  99                 added = 0;
 100                 while (added == 0 && locale_alias_path[0] != '\0') {
 101                         const unsigned char *start;
 102
 103                         while (locale_alias_path[0] == PATH_SEPARATOR)
 104                                 ++locale_alias_path;
 105                         start = locale_alias_path;
 106
 107                         while (locale_alias_path[0] != '\0'
 108                                && locale_alias_path[0] != PATH_SEPARATOR)
 109                                 ++locale_alias_path;
 110
 111                         if (start < locale_alias_path)
 112                                 added = read_alias_file(start,
 113                                                         locale_alias_path -
 114                                                         start);
 115                 }
 116         }
 117         while (added != 0);
 118
 119         return result;
 120 }
 121
 122 static size_t
 123 read_alias_file(const unsigned char *fname, int fname_len)
 124 {
 125         FILE *fp;
 126         unsigned char *full_fname;
 127         size_t added;
 128         static const unsigned char aliasfile[] = "/locale.alias";
 129
 130         full_fname = (unsigned char *) fmem_alloc(fname_len + sizeof(aliasfile));
 131         mempcpy(mempcpy(full_fname, fname, fname_len),
 132                 aliasfile, sizeof(aliasfile));
 133
 134         fp = fopen(full_fname, "rb");
 135         fmem_free(full_fname);
 136         if (fp == NULL)
 137                 return 0;
 138
 139         added = 0;
 140         while (!feof(fp)) {
 141                 /* It is a reasonable approach to use a fix buffer here because
 142                    a) we are only interested in the first two fields
 143                    b) these fields must be usable as file names and so must not
 144                    be that long
 145                  */
 146                 unsigned char buf[BUFSIZ];
 147                 unsigned char *alias;
 148                 unsigned char *value;
 149                 unsigned char *cp;
 150
 151                 if (fgets(buf, sizeof(buf), fp) == NULL)
 152                         /* EOF reached.  */
 153                         break;
 154
 155                 /* Possibly not the whole line fits into the buffer.  Ignore
 156                    the rest of the line.  */
 157                 if (strchr(buf, '\n') == NULL) {
 158                         unsigned char altbuf[BUFSIZ];
 159
 160                         do
 161                                 if (fgets(altbuf, sizeof(altbuf), fp) == NULL)
 162                                         /* Make sure the inner loop will be left.  The outer loop
 163                                            will exit at the `feof' test.  */
 164                                         break;
 165                         while (strchr(altbuf, '\n') == NULL);
 166                 }
 167
 168                 cp = buf;
 169                 /* Ignore leading white space.  */
 170                 skip_space(cp);
 171
 172                 /* A leading '#' signals a comment line.  */
 173                 if (cp[0] != '\0' && cp[0] != '#') {
 174                         alias = cp++;
 175                         skip_nonspace(cp);
 176                         /* Terminate alias name.  */
 177                         if (cp[0] != '\0')
 178                                 *cp++ = '\0';
 179
 180                         /* Now look for the beginning of the value.  */
 181                         skip_space(cp);
 182
 183                         if (cp[0] != '\0') {
 184                                 size_t alias_len;
 185                                 size_t value_len;
 186
 187                                 value = cp++;
 188                                 skip_nonspace(cp);
 189                                 /* Terminate value.  */
 190                                 if (cp[0] == '\n') {
 191                                         /* This has to be done to make the following test
 192                                            for the end of line possible.  We are looking for
 193                                            the terminating '\n' which do not overwrite here.  */
 194                                         *cp++ = '\0';
 195                                         *cp = '\n';
 196                                 } else if (cp[0] != '\0')
 197                                         *cp++ = '\0';
 198
 199                                 if (nmap >= maxmap)
 200                                         if (extend_alias_table())
 201                                                 return added;
 202
 203                                 alias_len = strlen(alias) + 1;
 204                                 value_len = strlen(value) + 1;
 205
 206                                 if (string_space_act + alias_len + value_len >
 207                                     string_space_max) {
 208                                         /* Increase size of memory pool.  */
 209                                         size_t new_size = (string_space_max
 210                                                            + (alias_len +
 211                                                               value_len >
 212                                                               1024 ? alias_len +
 213                                                               value_len :
 214                                                               1024));
 215                                         unsigned char *new_pool =
 216                                                 (unsigned char *) realloc(string_space,
 217                                                                  new_size);
 218                                         if (new_pool == NULL)
 219                                                 return added;
 220
 221                                         if (string_space != new_pool) {
 222                                                 size_t i;
 223
 224                                                 for (i = 0; i < nmap; i++) {
 225                                                         map[i].alias +=
 226                                                                 new_pool -
 227                                                                 string_space;
 228                                                         map[i].value +=
 229                                                                 new_pool -
 230                                                                 string_space;
 231                                                 }
 232                                         }
 233
 234                                         string_space = new_pool;
 235                                         string_space_max = new_size;
 236                                 }
 237
 238                                 map[nmap].alias =
 239                                         memcpy(&string_space[string_space_act],
 240                                                alias, alias_len);
 241                                 string_space_act += alias_len;
 242
 243                                 map[nmap].value =
 244                                         memcpy(&string_space[string_space_act],
 245                                                value, value_len);
 246                                 string_space_act += value_len;
 247
 248                                 ++nmap;
 249                                 ++added;
 250                         }
 251                 }
 252         }
 253
 254         /* Should we test for ferror()?  I think we have to silently ignore
 255            errors.  --drepper  */
 256         fclose(fp);
 257
 258         if (added > 0)
 259                 qsort(map, nmap, sizeof(struct alias_map),
 260                       (int (*)(const void *, const void *))
 261                       alias_compare);
 262
 263         return added;
 264 }
 265
 266 static int
 267 extend_alias_table(void)
 268 {
 269         size_t new_size;
 270         struct alias_map *new_map;
 271
 272         new_size = maxmap == 0 ? 100 : 2 * maxmap;
 273         new_map = (struct alias_map *) realloc(map, (new_size
 274                                                      *
 275                                                      sizeof(struct alias_map)));
 276         if (new_map == NULL)
 277                 /* Simply don't extend: we don't have any more core.  */
 278                 return -1;
 279
 280         map = new_map;
 281         maxmap = new_size;
 282         return 0;
 283 }
 284
 285 static int
 286 alias_compare(const struct alias_map *map1, const struct alias_map *map2)
 287 {
 288         return c_strcasecmp(map1->alias, map2->alias);
 289 }