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  #include <string.h>
      21  
      22  /* Look up the value of the next multibyte character and return its numerical
      23     value if it is one of the digits known in the locale.  If *DECIDED is
      24     -1 this means it is not yet decided which form it is and we have to
      25     search through all available digits.  Otherwise we know which script
      26     the digits are from.  */
      27  static inline int
      28  indigit_value (const char **s, size_t *len, int *decided)
      29  {
      30    int from_level;
      31    int to_level;
      32    const char *mbdigits[10];
      33    int i;
      34    int n;
      35  
      36    if (*decided != -1)
      37      from_level = to_level = *decided;
      38    else
      39      {
      40        from_level = 0;
      41        to_level = _NL_CURRENT_WORD (LC_CTYPE, _NL_CTYPE_INDIGITS_MB_LEN) - 1;
      42        assert (from_level <= to_level);
      43      }
      44  
      45    /* In this round we get the pointer to the digit strings and also perform
      46       the first round of comparisons.  */
      47    for (n = 0; n < 10; ++n)
      48      {
      49        size_t dlen;
      50  
      51        /* Get the string for the digits with value N.  */
      52        mbdigits[n] = _NL_CURRENT (LC_CTYPE, _NL_CTYPE_INDIGITS0_MB + n);
      53        dlen = strlen (mbdigits[n]);
      54  
      55        if (from_level == 0 && dlen <= *len
      56  	  && memcmp (*s, mbdigits[n], dlen) == 0)
      57  	{
      58  	  /* Found it.  */
      59  	  *s += dlen;
      60  	  *len -= dlen;
      61  	  if (*decided == -1)
      62  	    *decided = 0;
      63  	  return n;
      64  	}
      65  
      66        /* Advance the pointer to the next string.  */
      67        mbdigits[n] += dlen + 1;
      68      }
      69  
      70    /* Now perform the remaining tests.  */
      71    for (i = 1; i <= to_level; ++i)
      72      {
      73        /* Search all ten digits of this level.  */
      74        for (n = 0; n < 10; ++n)
      75  	{
      76  	  size_t dlen = strlen (mbdigits[n]);
      77  
      78  	  if (i >= from_level && dlen <= *len
      79  	      && memcmp (*s, mbdigits[n], dlen) == 0)
      80  	    {
      81  	      /* Found it.  */
      82  	      *s += dlen;
      83  	      *len -= dlen;
      84  	      if (*decided == -1)
      85  		*decided = from_level;
      86  	      return n;
      87  	    }
      88  
      89  	  /* Advance the pointer to the next string.  */
      90  	  mbdigits[n] += dlen + 1;
      91  	}
      92      }
      93  
      94    /* If we reach this point no matching digit was found.  */
      95    return -1;
      96  }