locale/loadlocale.c

   1 /* Functions to read locale data files.
   2    Copyright (C) 1996, 1997, 1998, 1999 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Ulrich Drepper <drepper@cygnus.com>, 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 not,
  18    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 #include <byteswap.h>
  22 #include <errno.h>
  23 #include <fcntl.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <unistd.h>
  27 #include <sys/mman.h>
  28 #include <sys/stat.h>
  29
  30 #include "localeinfo.h"
  31
  32
  33 static const size_t _nl_category_num_items[] =
  34 {
  35 #define DEFINE_CATEGORY(category, category_name, items, a) \
  36   [category] = _NL_ITEM_INDEX (_NL_NUM_##category),
  37 #include "categories.def"
  38 #undef  DEFINE_CATEGORY
  39 };
  40
  41
  42 #define NO_PAREN(arg, rest...) arg, ##rest
  43
  44 #define DEFINE_CATEGORY(category, category_name, items, a) \
  45 static const enum value_type _nl_value_type_##category[] = { NO_PAREN items };
  46 #define DEFINE_ELEMENT(element, element_name, optstd, type, rest...) \
  47   [_NL_ITEM_INDEX (element)] = type,
  48 #include "categories.def"
  49 #undef DEFINE_CATEGORY
  50
  51 static const enum value_type *_nl_value_types[] =
  52 {
  53 #define DEFINE_CATEGORY(category, category_name, items, a) \
  54   [category] = _nl_value_type_##category,
  55 #include "categories.def"
  56 #undef DEFINE_CATEGORY
  57 };
  58
  59
  60 void
  61 _nl_load_locale (struct loaded_l10nfile *file, int category)
  62 {
  63   int fd;
  64   struct
  65     {
  66       unsigned int magic;
  67       unsigned int nstrings;
  68       unsigned int strindex[0];
  69     } *filedata;
  70   struct stat st;
  71   struct locale_data *newdata;
  72   int save_err;
  73   int swap = 0;
  74   int mmaped = 1;
  75   size_t cnt;
  76   inline unsigned int SWAP (const unsigned int *inw)
  77     {
  78       if (!swap)
  79         return *inw;
  80       return bswap_32 (*inw);
  81     }
  82
  83   file->decided = 1;
  84   file->data = NULL;
  85
  86   fd = __open (file->filename, O_RDONLY);
  87   if (fd < 0)
  88     /* Cannot open the file.  */
  89     return;
  90
  91   if (__fstat (fd, &st) < 0)
  92     goto puntfd;
  93   if (S_ISDIR (st.st_mode))
  94     {
  95       /* LOCALE/LC_foo is a directory; open LOCALE/LC_foo/SYS_LC_foo
  96            instead.  */
  97       char *newp;
  98
  99       __close (fd);
 100
 101       newp = (char *) alloca (strlen (file->filename)
 102                               + 5 + _nl_category_name_sizes[category] + 1);
 103       __stpcpy (__stpcpy (__stpcpy (newp, file->filename), "/SYS_"),
 104                 _nl_category_names[category]);
 105
 106       fd = __open (newp, O_RDONLY);
 107       if (fd < 0)
 108         return;
 109
 110       if (__fstat (fd, &st) < 0)
 111         goto puntfd;
 112     }
 113
 114   /* Map in the file's data.  */
 115   save_err = errno;
 116 #ifndef MAP_COPY
 117   /* Linux seems to lack read-only copy-on-write.  */
 118 #define MAP_COPY MAP_PRIVATE
 119 #endif
 120 #ifndef MAP_FILE
 121   /* Some systems do not have this flag; it is superfluous.  */
 122 #define MAP_FILE 0
 123 #endif
 124 #ifndef MAP_INHERIT
 125   /* Some systems might lack this; they lose.  */
 126 #define MAP_INHERIT 0
 127 #endif
 128   filedata = (void *) __mmap ((caddr_t) 0, st.st_size, PROT_READ,
 129                               MAP_FILE|MAP_COPY|MAP_INHERIT, fd, 0);
 130   if ((void *) filedata == MAP_FAILED)
 131     {
 132       if (errno == ENOSYS)
 133         {
 134           /* No mmap; allocate a buffer and read from the file.  */
 135           mmaped = 0;
 136           filedata = malloc (st.st_size);
 137           if (filedata != NULL)
 138             {
 139               off_t to_read = st.st_size;
 140               ssize_t nread;
 141               char *p = (char *) filedata;
 142               while (to_read > 0)
 143                 {
 144                   nread = __read (fd, p, to_read);
 145                   if (nread <= 0)
 146                     {
 147                       free (filedata);
 148                       if (nread == 0)
 149                         __set_errno (EINVAL); /* Bizarreness going on.  */
 150                       goto puntfd;
 151                     }
 152                   p += nread;
 153                   to_read -= nread;
 154                 }
 155             }
 156           else
 157             goto puntfd;
 158           __set_errno (save_err);
 159         }
 160       else
 161         goto puntfd;
 162     }
 163   else if (st.st_size < sizeof (*filedata))
 164     /* This cannot be a locale data file since it's too small.  */
 165     goto puntfd;
 166
 167   if (filedata->magic == LIMAGIC (category))
 168     /* Good data file in our byte order.  */
 169     swap = 0;
 170   else
 171     {
 172       /* Try the other byte order.  */
 173       swap = 1;
 174       if (SWAP (&filedata->magic) != LIMAGIC (category))
 175         /* Bad data file in either byte order.  */
 176         {
 177         puntmap:
 178           __munmap ((caddr_t) filedata, st.st_size);
 179         puntfd:
 180           __close (fd);
 181           return;
 182         }
 183     }
 184
 185 #define W(word) SWAP (&(word))
 186
 187   if (W (filedata->nstrings) < _nl_category_num_items[category] ||
 188       (sizeof *filedata + W (filedata->nstrings) * sizeof (unsigned int)
 189        >= (size_t) st.st_size))
 190     {
 191       /* Insufficient data.  */
 192       __set_errno (EINVAL);
 193       goto puntmap;
 194     }
 195
 196   newdata = malloc (sizeof *newdata
 197                     + (_nl_category_num_items[category]
 198                        * sizeof (union locale_data_value)));
 199   if (! newdata)
 200     goto puntmap;
 201
 202   newdata->name = NULL; /* This will be filled if necessary in findlocale.c. */
 203   newdata->filedata = (void *) filedata;
 204   newdata->filesize = st.st_size;
 205   newdata->mmaped = mmaped;
 206   newdata->usage_count = 0;
 207   newdata->nstrings = _nl_category_num_items[category];
 208   for (cnt = 0; cnt < newdata->nstrings; ++cnt)
 209     {
 210       off_t idx = W (filedata->strindex[cnt]);
 211       if (idx >= newdata->filesize)
 212         {
 213           free (newdata);
 214           __set_errno (EINVAL);
 215           goto puntmap;
 216         }
 217       if (_nl_value_types[category][cnt] == word)
 218         newdata->values[cnt].word = W (*((u_int32_t *) (newdata->filedata
 219                                                         + idx)));
 220       else
 221         newdata->values[cnt].string = newdata->filedata + idx;
 222     }
 223
 224   __close (fd);
 225   file->data = newdata;
 226 }
 227
 228 void
 229 _nl_unload_locale (struct locale_data *locale)
 230 {
 231   if (locale->mmaped)
 232     __munmap ((caddr_t) locale->filedata, locale->filesize);
 233   else
 234     free ((void *) locale->filedata);
 235
 236   free (locale);
 237 }