1  /* Compute the printf width of a sequence of ASCII digits.
       2     Copyright (C) 2022-2023 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     <https://www.gnu.org/licenses/>.  */
      18  
      19  #include <assert.h>
      20  #include <limits.h>
      21  #include <locale/localeinfo.h>
      22  #include <printf.h>
      23  
      24  int
      25  __translated_number_width (locale_t loc, const char *first, const char *last)
      26  {
      27    struct lc_ctype_data *ctype = loc->__locales[LC_CTYPE]->private;
      28  
      29    if (ctype->outdigit_bytes_all_equal > 0)
      30      return (last - first) * ctype->outdigit_bytes_all_equal;
      31    else
      32      {
      33        /* Digits have varying length, so the fast path cannot be used.  */
      34        int digits = 0;
      35        for (const char *p = first; p < last; ++p)
      36          {
      37            assert ('0' <= *p && *p <= '9');
      38            digits += ctype->outdigit_bytes[*p - '0'];
      39          }
      40        return digits;
      41      }
      42  }