locale/loadlocale.c

   1 /* Functions to read locale data files.
   2 Copyright (C) 1996 Free Software Foundation, Inc.
   3 This file is part of the GNU C Library.
   4 Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1996.
   5
   6 The GNU C Library is free software; you can redistribute it and/or
   7 modify it under the terms of the GNU Library General Public License as
   8 published by the Free Software Foundation; either version 2 of the
   9 License, or (at your option) any later version.
  10
  11 The GNU C Library is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 Library General Public License for more details.
  15
  16 You should have received a copy of the GNU Library General Public
  17 License along with the GNU C Library; see the file COPYING.LIB.  If
  18 not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21 #include <errno.h>
  22 #include <fcntl.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <unistd.h>
  26 #include <sys/mman.h>
  27 #include <sys/stat.h>
  28
  29 #include "localeinfo.h"
  30
  31
  32 static const size_t _nl_category_num_items[] =
  33 {
  34 #define DEFINE_CATEGORY(category, category_name, items, a, b, c, d) \
  35   [category] = _NL_ITEM_INDEX (_NL_NUM_##category),
  36 #include "categories.def"
  37 #undef  DEFINE_CATEGORY
  38 };
  39
  40
  41 #define NO_PAREN(arg, rest...) arg, ##rest
  42
  43 #define DEFINE_CATEGORY(category, category_name, items, a, b, c, d) \
  44 static const enum value_type _nl_value_type_##category[] = { NO_PAREN items };
  45 #define DEFINE_ELEMENT(element, element_name, optstd, type, rest...) \
  46   [_NL_ITEM_INDEX (element)] = type,
  47 #include "categories.def"
  48 #undef DEFINE_CATEGORY
  49
  50 static const enum value_type *_nl_value_types[] =
  51 {
  52 #define DEFINE_CATEGORY(category, category_name, items, a, b, c, d) \
  53   [category] = _nl_value_type_##category,
  54 #include "categories.def"
  55 #undef DEFINE_CATEGORY
  56 };
  57
  58
  59 void
  60 _nl_load_locale (struct loaded_l10nfile *file, int category)
  61 {
  62   int fd;
  63   struct
  64     {
  65       unsigned int magic;
  66       unsigned int nstrings;
  67       unsigned int strindex[0];
  68     } *filedata;
  69   struct stat st;
  70   struct locale_data *newdata;
  71   int save_err;
  72   int swap = 0;
  73   size_t cnt;
  74   inline unsigned int SWAP (const unsigned int *inw)
  75     {
  76       const unsigned char *inc = (const unsigned char *) inw;
  77       if (!swap)
  78         return *inw;
  79       return (inc[3] << 24) | (inc[2] << 16) | (inc[1] << 8) | inc[0];
  80     }
  81
  82   file->decided = 1;
  83   file->data = NULL;
  84
  85   fd = __open (file->filename, O_RDONLY);
  86   if (fd < 0)
  87     /* Cannot open the file.  */
  88     return;
  89
  90   if (__fstat (fd, &st) < 0)
  91     goto puntfd;
  92   if (S_ISDIR (st.st_mode))
  93     {
  94       /* LOCALE/LC_foo is a directory; open LOCALE/LC_foo/SYS_LC_foo
  95            instead.  */
  96       char *newp;
  97
  98       __close (fd);
  99
 100       newp = (char *) alloca (strlen (file->filename)
 101                               + 5 + _nl_category_name_sizes[category] + 1);
 102       __stpcpy (__stpcpy (__stpcpy (newp, file->filename), "/SYS_"),
 103                 _nl_category_names[category]);
 104
 105       fd = __open (newp, O_RDONLY);
 106       if (fd < 0)
 107         return;
 108
 109       if (__fstat (fd, &st) < 0)
 110         goto puntfd;
 111     }
 112
 113   /* Map in the file's data.  */
 114   save_err = errno;
 115 #ifndef MAP_COPY
 116   /* Linux seems to lack read-only copy-on-write.  */
 117 #define MAP_COPY MAP_PRIVATE
 118 #endif
 119 #ifndef MAP_FILE
 120   /* Some systems do not have this flag; it is superfluous.  */
 121 #define MAP_FILE 0
 122 #endif
 123 #ifndef MAP_INHERIT
 124   /* Some systems might lack this; they lose.  */
 125 #define MAP_INHERIT 0
 126 #endif
 127   filedata = (void *) __mmap ((caddr_t) 0, st.st_size, PROT_READ,
 128                               MAP_FILE|MAP_COPY|MAP_INHERIT, fd, 0);
 129   if (filedata == (void *) -1)
 130     {
 131       if (errno == ENOSYS)
 132         {
 133           /* No mmap; allocate a buffer and read from the file.  */
 134           filedata = malloc (st.st_size);
 135           if (filedata != NULL)
 136             {
 137               off_t to_read = st.st_size;
 138               ssize_t nread;
 139               char *p = (char *) filedata;
 140               while (to_read > 0)
 141                 {
 142                   nread = __read (fd, p, to_read);
 143                   if (nread <= 0)
 144                     {
 145                       free (filedata);
 146                       if (nread == 0)
 147                         __set_errno (EINVAL); /* Bizarreness going on.  */
 148                       goto puntfd;
 149                     }
 150                   p += nread;
 151                   to_read -= nread;
 152                 }
 153             }
 154           else
 155             goto puntfd;
 156           __set_errno (save_err);
 157         }
 158       else
 159         goto puntfd;
 160     }
 161
 162   if (filedata->magic == LIMAGIC (category))
 163     /* Good data file in our byte order.  */
 164     swap = 0;
 165   else
 166     {
 167       /* Try the other byte order.  */
 168       swap = 1;
 169       if (SWAP (&filedata->magic) != LIMAGIC (category))
 170         /* Bad data file in either byte order.  */
 171         {
 172         puntmap:
 173           __munmap ((caddr_t) filedata, st.st_size);
 174         puntfd:
 175           __close (fd);
 176           return;
 177         }
 178     }
 179
 180 #define W(word) SWAP (&(word))
 181
 182   if (W (filedata->nstrings) < _nl_category_num_items[category] ||
 183       (sizeof *filedata + W (filedata->nstrings) * sizeof (unsigned int)
 184        >= (size_t) st.st_size))
 185     {
 186       /* Insufficient data.  */
 187       __set_errno (EINVAL);
 188       goto puntmap;
 189     }
 190
 191   newdata = malloc (sizeof *newdata +
 192                     (_nl_category_num_items[category]
 193                      * sizeof (union locale_data_value)));
 194   if (! newdata)
 195     goto puntmap;
 196
 197   newdata->name = NULL; /* This will be filled if necessary in findlocale.c. */
 198   newdata->filedata = (void *) filedata;
 199   newdata->filesize = st.st_size;
 200   newdata->nstrings = _nl_category_num_items[category];
 201   for (cnt = 0; cnt < newdata->nstrings; ++cnt)
 202     {
 203       off_t idx = W (filedata->strindex[cnt]);
 204       if (idx >= newdata->filesize)
 205         {
 206           free (newdata);
 207           __set_errno (EINVAL);
 208           goto puntmap;
 209         }
 210       if (_nl_value_types[category][cnt] == word)
 211         newdata->values[cnt].word = W (*((u_int32_t *) (newdata->filedata
 212                                                         + idx)));
 213       else
 214         newdata->values[cnt].string = newdata->filedata + idx;
 215     }
 216
 217   __close (fd);
 218   file->data = newdata;
 219 }