time/alt_digit.c

   1 /* Helper functions used by strftime/strptime to handle alternate digits.
   2    Copyright (C) 1995-2002, 2008, 2010 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   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, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include "../locale/localeinfo.h"
  20 #include <bits/libc-lock.h>
  21 #include <stdlib.h>
  22 #include <wchar.h>
  23 #include <string.h>
  24
  25 /* Some of the functions here must not be used while setlocale is called.  */
  26 __libc_rwlock_define (extern, __libc_setlocale_lock attribute_hidden)
  27
  28 #define CURRENT(item) (current->values[_NL_ITEM_INDEX (item)].string)
  29 #define CURRENT_WSTR(item) \
  30   ((wchar_t *) current->values[_NL_ITEM_INDEX (item)].wstr)
  31
  32 static void
  33 _nl_init_alt_digit (struct __locale_data *current)
  34 {
  35   struct lc_time_data *data;
  36
  37   if (current->private.time == NULL)
  38     {
  39       current->private.time = malloc (sizeof *current->private.time);
  40       if (current->private.time == NULL)
  41         return;
  42       memset (current->private.time, 0, sizeof *current->private.time);
  43       current->private.cleanup = &_nl_cleanup_time;
  44     }
  45   data = current->private.time;
  46
  47   if (! data->alt_digits_initialized)
  48     {
  49       const char *ptr = CURRENT (ALT_DIGITS);
  50       size_t cnt;
  51
  52       data->alt_digits_initialized = 1;
  53
  54       if (ptr != NULL)
  55         {
  56           data->alt_digits = malloc (100 * sizeof (const char *));
  57           if (data->alt_digits != NULL)
  58             for (cnt = 0; cnt < 100; ++cnt)
  59               {
  60                 data->alt_digits[cnt] = ptr;
  61
  62                 /* Skip digit format. */
  63                 ptr = strchr (ptr, '\0') + 1;
  64               }
  65         }
  66     }
  67
  68 }
  69
  70 const char *
  71 internal_function
  72 _nl_get_alt_digit (unsigned int number, struct __locale_data *current)
  73 {
  74   const char *result;
  75
  76   if (number >= 100 || CURRENT (ALT_DIGITS)[0] == '\0')
  77     return NULL;
  78
  79   __libc_rwlock_wrlock (__libc_setlocale_lock);
  80
  81   if (current->private.time == NULL
  82       || ! current->private.time->alt_digits_initialized)
  83     _nl_init_alt_digit (current);
  84
  85   result = ((current->private.time != NULL
  86              && current->private.time->alt_digits != NULL)
  87             ? current->private.time->alt_digits[number]
  88             : NULL);
  89
  90   __libc_rwlock_unlock (__libc_setlocale_lock);
  91
  92   return result;
  93 }
  94
  95
  96 const wchar_t *
  97 internal_function
  98 _nl_get_walt_digit (unsigned int number, struct __locale_data *current)
  99 {
 100   const wchar_t *result = NULL;
 101   struct lc_time_data *data;
 102
 103   if (number >= 100 || CURRENT_WSTR (_NL_WALT_DIGITS)[0] == L'\0')
 104     return NULL;
 105
 106   __libc_rwlock_wrlock (__libc_setlocale_lock);
 107
 108   if (current->private.time == NULL)
 109     {
 110       current->private.time = malloc (sizeof *current->private.time);
 111       if (current->private.time == NULL)
 112         goto out;
 113       memset (current->private.time, 0, sizeof *current->private.time);
 114       current->private.cleanup = &_nl_cleanup_time;
 115     }
 116   data = current->private.time;
 117
 118   if (! data->walt_digits_initialized)
 119     {
 120       const wchar_t *ptr = CURRENT_WSTR (_NL_WALT_DIGITS);
 121       size_t cnt;
 122
 123       data->walt_digits_initialized = 1;
 124
 125       if (ptr != NULL)
 126         {
 127           data->walt_digits = malloc (100 * sizeof (const uint32_t *));
 128           if (data->walt_digits != NULL)
 129             for (cnt = 0; cnt < 100; ++cnt)
 130               {
 131                 data->walt_digits[cnt] = ptr;
 132
 133                 /* Skip digit format. */
 134                 ptr = wcschr (ptr, L'\0') + 1;
 135               }
 136         }
 137     }
 138
 139   if (data->walt_digits != NULL)
 140     result = data->walt_digits[number];
 141
 142  out:
 143   __libc_rwlock_unlock (__libc_setlocale_lock);
 144
 145   return (wchar_t *) result;
 146 }
 147
 148
 149 int
 150 internal_function
 151 _nl_parse_alt_digit (const char **strp, struct __locale_data *current)
 152 {
 153   const char *str = *strp;
 154   int result = -1;
 155   size_t cnt;
 156   size_t maxlen = 0;
 157
 158   if (CURRENT_WSTR (_NL_WALT_DIGITS)[0] == L'\0')
 159     return result;
 160
 161   __libc_rwlock_wrlock (__libc_setlocale_lock);
 162
 163   if (current->private.time == NULL
 164       || ! current->private.time->alt_digits_initialized)
 165     _nl_init_alt_digit (current);
 166
 167   if (current->private.time != NULL &&
 168       current->private.time->alt_digits != NULL)
 169     /* Matching is not unambiguous.  The alternative digits could be like
 170        I, II, III, ... and the first one is a substring of the second
 171        and third.  Therefore we must keep on searching until we found
 172        the longest possible match.  Note that this is not specified in
 173        the standard.  */
 174     for (cnt = 0; cnt < 100; ++cnt)
 175       {
 176         const char *const dig = current->private.time->alt_digits[cnt];
 177         size_t len = strlen (dig);
 178
 179         if (len > maxlen && strncmp (dig, str, len) == 0)
 180           {
 181             maxlen = len;
 182             result = (int) cnt;
 183           }
 184       }
 185
 186   __libc_rwlock_unlock (__libc_setlocale_lock);
 187
 188   if (result != -1)
 189     *strp += maxlen;
 190
 191   return result;
 192 }