wcsmbs/wcsmbsload.c

   1 /* Copyright (C) 1998, 1999, 2000 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include <ctype.h>
  21 #include <langinfo.h>
  22 #include <limits.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25
  26 #include <locale/localeinfo.h>
  27 #include <wcsmbsload.h>
  28 #include <bits/libc-lock.h>
  29 #include <iconv/gconv_int.h>
  30
  31
  32 /* Last loaded locale for LC_CTYPE.  We initialize for the C locale
  33    which is enabled at startup.  */
  34 extern const struct locale_data _nl_C_LC_CTYPE;
  35 const struct locale_data *__wcsmbs_last_locale = &_nl_C_LC_CTYPE;
  36
  37
  38 /* These are the descriptions for the default conversion functions.  */
  39 static struct __gconv_step to_wc =
  40 {
  41   .__shlib_handle = NULL,
  42   .__modname = NULL,
  43   .__counter = INT_MAX,
  44   .__from_name = "ANSI_X3.4-1968//TRANSLIT",
  45   .__to_name = "INTERNAL",
  46   .__fct = __gconv_transform_ascii_internal,
  47   .__init_fct = NULL,
  48   .__end_fct = NULL,
  49   .__min_needed_from = 1,
  50   .__max_needed_from = 1,
  51   .__min_needed_to = 4,
  52   .__max_needed_to = 4,
  53   .__stateful = 0,
  54   .__data = NULL
  55 };
  56
  57 static struct __gconv_step to_mb =
  58 {
  59   .__shlib_handle = NULL,
  60   .__modname = NULL,
  61   .__counter = INT_MAX,
  62   .__from_name = "INTERNAL",
  63   .__to_name = "ANSI_X3.4-1968//TRANSLIT",
  64   .__fct = __gconv_transform_internal_ascii,
  65   .__init_fct = NULL,
  66   .__end_fct = NULL,
  67   .__min_needed_from = 4,
  68   .__max_needed_from = 4,
  69   .__min_needed_to = 1,
  70   .__max_needed_to = 1,
  71   .__stateful = 0,
  72   .__data = NULL
  73 };
  74
  75
  76 /* For the default locale we only have to handle ANSI_X3.4-1968.  */
  77 struct gconv_fcts __wcsmbs_gconv_fcts =
  78 {
  79   .towc = &to_wc,
  80   .tomb = &to_mb
  81 };
  82
  83
  84 static inline struct __gconv_step *
  85 getfct (const char *to, const char *from)
  86 {
  87   size_t nsteps;
  88   struct __gconv_step *result;
  89   size_t nstateful;
  90   size_t cnt;
  91
  92   if (__gconv_find_transform (to, from, &result, &nsteps, 0) != __GCONV_OK)
  93     /* Loading the conversion step is not possible.  */
  94     return NULL;
  95
  96   /* Count the number of stateful conversions.  Since we will only
  97      have one 'mbstate_t' object available we can only deal with one
  98      stateful conversion.  */
  99   nstateful = 0;
 100   for (cnt = 0; cnt < nsteps; ++cnt)
 101     if (result[cnt].__stateful)
 102       ++nstateful;
 103   if (nstateful > 1)
 104     {
 105       /* We cannot handle this case.  */
 106       __gconv_close_transform (result, nsteps);
 107       result = NULL;
 108     }
 109
 110   return result;
 111 }
 112
 113
 114 /* Extract from the given locale name the character set portion.  Since
 115    only the XPG form of the name includes this information we don't have
 116    to take care for the CEN form.  */
 117 #define extract_charset_name(str) \
 118   ({                                                                          \
 119     const char *cp = str;                                                     \
 120     char *result = NULL;                                                      \
 121                                                                               \
 122     cp += strcspn (cp, "@.+,");                                               \
 123     if (*cp == '.')                                                           \
 124       {                                                                       \
 125         const char *endp = ++cp;                                              \
 126         while (*endp != '\0' && *endp != '@')                                 \
 127           ++endp;                                                             \
 128         if (endp != cp)                                                       \
 129           result = strndupa (cp, endp - cp);                                  \
 130       }                                                                       \
 131     result;                                                                   \
 132   })
 133
 134
 135 /* We must modify global data.  */
 136 __libc_lock_define_initialized (static, lock)
 137
 138
 139 /* Load conversion functions for the currently selected locale.  */
 140 void
 141 internal_function
 142 __wcsmbs_load_conv (const struct locale_data *new_category)
 143 {
 144   /* Acquire the lock.  */
 145   __libc_lock_lock (lock);
 146
 147   /* We should repeat the test since while we waited some other thread
 148      might have run this function.  */
 149   if (__builtin_expect (__wcsmbs_last_locale != new_category, 1))
 150     {
 151       if (new_category->name == _nl_C_name)     /* Yes, pointer comparison.  */
 152         {
 153         failed:
 154           __wcsmbs_gconv_fcts.towc = &to_wc;
 155           __wcsmbs_gconv_fcts.tomb = &to_mb;
 156         }
 157       else
 158         {
 159           /* We must find the real functions.  */
 160           const char *charset_name;
 161           const char *complete_name;
 162           struct __gconv_step *new_towc;
 163           struct __gconv_step *new_tomb;
 164           int use_translit;
 165
 166           /* Free the old conversions.  */
 167           __gconv_close_transform (__wcsmbs_gconv_fcts.tomb, 1);
 168           __gconv_close_transform (__wcsmbs_gconv_fcts.towc, 1);
 169
 170           /* Get name of charset of the locale.  */
 171           charset_name = new_category->values[_NL_ITEM_INDEX(CODESET)].string;
 172
 173           /* Does the user want transliteration?  */
 174           use_translit = new_category->use_translit;
 175
 176           /* Normalize the name and add the slashes necessary for a
 177              complete lookup.  */
 178           complete_name = norm_add_slashes (charset_name,
 179                                             use_translit ? "TRANSLIT" : NULL);
 180
 181           /* It is not necessary to use transliteration in this direction
 182              since the internal character set is supposed to be able to
 183              represent all others.  */
 184           new_towc = getfct ("INTERNAL", complete_name);
 185           new_tomb = (new_towc != NULL
 186                       ? getfct (complete_name, "INTERNAL") : NULL);
 187
 188           /* If any of the conversion functions is not available we don't
 189              use any since this would mean we cannot convert back and
 190              forth.*/
 191           if (new_towc == NULL || new_tomb == NULL)
 192             {
 193               if (new_towc != NULL)
 194                 __gconv_close_transform (new_towc, 1);
 195
 196               goto failed;
 197             }
 198
 199           __wcsmbs_gconv_fcts.tomb = new_tomb;
 200           __wcsmbs_gconv_fcts.towc = new_towc;
 201         }
 202
 203       /* Set last-used variable for current locale.  */
 204       __wcsmbs_last_locale = new_category;
 205     }
 206
 207   __libc_lock_unlock (lock);
 208 }
 209
 210
 211 /* Clone the current conversion function set.  */
 212 void
 213 internal_function
 214 __wcsmbs_clone_conv (struct gconv_fcts *copy)
 215 {
 216   /* First make sure the function table is up-to-date.  */
 217   update_conversion_ptrs ();
 218
 219   /* Make sure the data structures remain the same until we are finished.  */
 220   __libc_lock_lock (lock);
 221
 222   /* Copy the data.  */
 223   *copy = __wcsmbs_gconv_fcts;
 224
 225   /* Now increment the usage counters.  */
 226   if (copy->towc->__shlib_handle != NULL)
 227     ++copy->towc->__counter;
 228   if (copy->tomb->__shlib_handle != NULL)
 229     ++copy->tomb->__counter;
 230
 231   __libc_lock_unlock (lock);
 232 }
 233
 234
 235 /* Clone the current conversion function set.  */
 236 int
 237 internal_function
 238 __wcsmbs_named_conv (struct gconv_fcts *copy, const char *name)
 239 {
 240   copy->towc = getfct ("INTERNAL", name);
 241   if (copy->towc != NULL)
 242     {
 243       copy->tomb = getfct (name, "INTERNAL");
 244       if (copy->tomb == NULL)
 245         __gconv_close_transform (copy->towc, 1);
 246     }
 247
 248   if (copy->towc == NULL || copy->tomb == NULL)
 249     return 1;
 250
 251   /* Now increment the usage counters.  */
 252   if (copy->towc->__shlib_handle != NULL)
 253     ++copy->towc->__counter;
 254   if (copy->tomb->__shlib_handle != NULL)
 255     ++copy->tomb->__counter;
 256
 257   return 0;
 258 }