locale/loadlocale.c

   1 /* Functions to read locale data files.
   2    Copyright (C) 1996, 1997, 1998 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 not,
  18    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 #ifdef _POSIX_MAPPED_FILES
  27 # include <sys/mman.h>
  28 #endif
  29 #include <sys/stat.h>
  30
  31 #include "localeinfo.h"
  32
  33
  34 static const size_t _nl_category_num_items[] =
  35 {
  36 #define DEFINE_CATEGORY(category, category_name, items, a, b, c, d) \
  37   [category] = _NL_ITEM_INDEX (_NL_NUM_##category),
  38 #include "categories.def"
  39 #undef  DEFINE_CATEGORY
  40 };
  41
  42
  43 #define NO_PAREN(arg, rest...) arg, ##rest
  44
  45 #define DEFINE_CATEGORY(category, category_name, items, a, b, c, d) \
  46 static const enum value_type _nl_value_type_##category[] = { NO_PAREN items };
  47 #define DEFINE_ELEMENT(element, element_name, optstd, type, rest...) \
  48   [_NL_ITEM_INDEX (element)] = type,
  49 #include "categories.def"
  50 #undef DEFINE_CATEGORY
  51
  52 static const enum value_type *_nl_value_types[] =
  53 {
  54 #define DEFINE_CATEGORY(category, category_name, items, a, b, c, d) \
  55   [category] = _nl_value_type_##category,
  56 #include "categories.def"
  57 #undef DEFINE_CATEGORY
  58 };
  59
  60
  61 void
  62 _nl_load_locale (struct loaded_l10nfile *file, int category)
  63 {
  64   int fd;
  65   struct
  66     {
  67       unsigned int magic;
  68       unsigned int nstrings;
  69       unsigned int strindex[0];
  70     } *filedata;
  71   struct stat st;
  72   struct locale_data *newdata;
  73   int save_err;
  74   int swap = 0;
  75   int mmaped = 1;
  76   size_t cnt;
  77   inline unsigned int SWAP (const unsigned int *inw)
  78     {
  79       const unsigned char *inc = (const unsigned char *) inw;
  80       if (!swap)
  81         return *inw;
  82       return (inc[3] << 24) | (inc[2] << 16) | (inc[1] << 8) | inc[0];
  83     }
  84
  85   file->decided = 1;
  86   file->data = NULL;
  87
  88   fd = __open (file->filename, O_RDONLY);
  89   if (fd < 0)
  90     /* Cannot open the file.  */
  91     return;
  92
  93   if (__fstat (fd, &st) < 0)
  94     goto puntfd;
  95   if (S_ISDIR (st.st_mode))
  96     {
  97       /* LOCALE/LC_foo is a directory; open LOCALE/LC_foo/SYS_LC_foo
  98            instead.  */
  99       char *newp;
 100
 101       __close (fd);
 102
 103       newp = (char *) alloca (strlen (file->filename)
 104                               + 5 + _nl_category_name_sizes[category] + 1);
 105       __stpcpy (__stpcpy (__stpcpy (newp, file->filename), "/SYS_"),
 106                 _nl_category_names[category]);
 107
 108       fd = __open (newp, O_RDONLY);
 109       if (fd < 0)
 110         return;
 111
 112       if (__fstat (fd, &st) < 0)
 113         goto puntfd;
 114     }
 115
 116   /* Map in the file's data.  */
 117   save_err = errno;
 118 #ifdef _POSIX_MAPPED_FILES
 119 # ifndef MAP_COPY
 120   /* Linux seems to lack read-only copy-on-write.  */
 121 #  define MAP_COPY MAP_PRIVATE
 122 # endif
 123 # ifndef MAP_FILE
 124   /* Some systems do not have this flag; it is superfluous.  */
 125 #  define MAP_FILE 0
 126 # endif
 127 # ifndef MAP_INHERIT
 128   /* Some systems might lack this; they lose.  */
 129 #  define MAP_INHERIT 0
 130 # endif
 131   filedata = (void *) __mmap ((caddr_t) 0, st.st_size, PROT_READ,
 132                               MAP_FILE|MAP_COPY|MAP_INHERIT, fd, 0);
 133   if ((void *) filedata != MAP_FAILED)
 134     {
 135       if (st.st_size < sizeof (*filedata))
 136         /* This cannot be a locale data file since it's too small.  */
 137         goto puntfd;
 138     }
 139   else
 140     {
 141       if (errno == ENOSYS)
 142         {
 143 #endif  /* _POSIX_MAPPED_FILES */
 144           /* No mmap; allocate a buffer and read from the file.  */
 145           mmaped = 0;
 146           filedata = malloc (st.st_size);
 147           if (filedata != NULL)
 148             {
 149               off_t to_read = st.st_size;
 150               ssize_t nread;
 151               char *p = (char *) filedata;
 152               while (to_read > 0)
 153                 {
 154                   nread = __read (fd, p, to_read);
 155                   if (nread <= 0)
 156                     {
 157                       free (filedata);
 158                       if (nread == 0)
 159                         __set_errno (EINVAL); /* Bizarreness going on.  */
 160                       goto puntfd;
 161                     }
 162                   p += nread;
 163                   to_read -= nread;
 164                 }
 165             }
 166           else
 167             goto puntfd;
 168           __set_errno (save_err);
 169 #ifdef _POSIX_MAPPED_FILES
 170         }
 171       else
 172         goto puntfd;
 173     }
 174 #endif  /* _POSIX_MAPPED_FILES */
 175
 176   if (filedata->magic == LIMAGIC (category))
 177     /* Good data file in our byte order.  */
 178     swap = 0;
 179   else
 180     {
 181       /* Try the other byte order.  */
 182       swap = 1;
 183       if (SWAP (&filedata->magic) != LIMAGIC (category))
 184         /* Bad data file in either byte order.  */
 185         {
 186         puntmap:
 187 #ifdef _POSIX_MAPPED_FILES
 188           if (mmaped)
 189             __munmap ((caddr_t) filedata, st.st_size);
 190           else
 191 #endif  /* _POSIX_MAPPED_FILES */
 192             free (filedata);
 193         puntfd:
 194           __close (fd);
 195           return;
 196         }
 197     }
 198
 199 #define W(word) SWAP (&(word))
 200
 201   if (W (filedata->nstrings) < _nl_category_num_items[category] ||
 202       (sizeof *filedata + W (filedata->nstrings) * sizeof (unsigned int)
 203        >= (size_t) st.st_size))
 204     {
 205       /* Insufficient data.  */
 206       __set_errno (EINVAL);
 207       goto puntmap;
 208     }
 209
 210   newdata = malloc (sizeof *newdata +
 211                     (_nl_category_num_items[category]
 212                      * sizeof (union locale_data_value)));
 213   if (! newdata)
 214     goto puntmap;
 215
 216   newdata->name = NULL; /* This will be filled if necessary in findlocale.c. */
 217   newdata->filedata = (void *) filedata;
 218   newdata->filesize = st.st_size;
 219   newdata->mmaped = mmaped;
 220   newdata->usage_count = 0;
 221   newdata->nstrings = _nl_category_num_items[category];
 222   for (cnt = 0; cnt < newdata->nstrings; ++cnt)
 223     {
 224       off_t idx = W (filedata->strindex[cnt]);
 225       if (idx >= newdata->filesize)
 226         {
 227           free (newdata);
 228           __set_errno (EINVAL);
 229           goto puntmap;
 230         }
 231       if (_nl_value_types[category][cnt] == word)
 232         newdata->values[cnt].word = W (*((u_int32_t *) (newdata->filedata
 233                                                         + idx)));
 234       else
 235         newdata->values[cnt].string = newdata->filedata + idx;
 236     }
 237
 238   __close (fd);
 239   file->data = newdata;
 240 }
 241
 242 void
 243 _nl_unload_locale (struct locale_data *locale)
 244 {
 245 #ifdef _POSIX_MAPPED_FILES
 246   if (locale->mmaped)
 247     __munmap ((caddr_t) locale->filedata, locale->filesize);
 248   else
 249 #endif
 250     free ((void *) locale->filedata);
 251
 252   free (locale);
 253 }