1  /* Copyright (C) 2000-2023 Free Software Foundation, Inc.
       2     This file is part of the GNU C Library.
       3  
       4     The GNU C Library is free software; you can redistribute it and/or
       5     modify it under the terms of the GNU Lesser General Public
       6     License as published by the Free Software Foundation; either
       7     version 2.1 of the License, or (at your option) any later version.
       8  
       9     The GNU C Library is distributed in the hope that it will be useful,
      10     but WITHOUT ANY WARRANTY; without even the implied warranty of
      11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      12     Lesser General Public License for more details.
      13  
      14     You should have received a copy of the GNU Lesser General Public
      15     License along with the GNU C Library; if not, see
      16     <https://www.gnu.org/licenses/>.  */
      17  
      18  #include <assert.h>
      19  #include <langinfo.h>
      20  
      21  /* Look up the value of the next multibyte character and return its numerical
      22     value if it is one of the digits known in the locale.  If *DECIDED is
      23     -1 this means it is not yet decided which form it is and we have to
      24     search through all available digits.  Otherwise we know which script
      25     the digits are from.  */
      26  static inline int
      27  indigitwc_value (wchar_t wc, int *decided)
      28  {
      29    int from_level;
      30    int to_level;
      31    const wchar_t *wcdigits[10];
      32    int n;
      33  
      34    if (*decided != -1)
      35      from_level = to_level = *decided;
      36    else
      37      {
      38        from_level = 0;
      39        to_level = _NL_CURRENT_WORD (LC_CTYPE, _NL_CTYPE_INDIGITS_WC_LEN) - 1;
      40        assert (from_level <= to_level);
      41      }
      42  
      43    /* In this round we get the pointer to the digit strings and also perform
      44       the first round of comparisons.  */
      45    for (n = 0; n < 10; ++n)
      46      {
      47        /* Get the string for the digits with value N.  */
      48        wcdigits[n] = _NL_CURRENT (LC_CTYPE, _NL_CTYPE_INDIGITS0_WC + n);
      49        wcdigits[n] += from_level;
      50  
      51        if (wc == *wcdigits[n])
      52  	{
      53  	  /* Found it.  */
      54  	  if (*decided == -1)
      55  	    *decided = 0;
      56  	  return n;
      57  	}
      58  
      59        /* Advance the pointer to the next string.  */
      60        ++wcdigits[n];
      61      }
      62  
      63    /* Now perform the remaining tests.  */
      64    while (++from_level <= to_level)
      65      {
      66        /* Search all ten digits of this level.  */
      67        for (n = 0; n < 10; ++n)
      68  	{
      69  	  if (wc == *wcdigits[n])
      70  	    {
      71  	      /* Found it.  */
      72  	      if (*decided == -1)
      73  		*decided = from_level;
      74  	      return n;
      75  	    }
      76  
      77  	  /* Advance the pointer to the next string.  */
      78  	  ++wcdigits[n];
      79  	}
      80      }
      81  
      82    /* If we reach this point no matching digit was found.  */
      83    return -1;
      84  }