root/maint/gnulib/lib/unistr/u-strcoll.h

/* */

INCLUDED FROM

DEFINITIONS

1. FUNC

   1 /* Compare UTF-8/UTF-16/UTF-32 strings using the collation rules of the current
   2    locale.
   3    Copyright (C) 2009-2021 Free Software Foundation, Inc.
   4    Written by Bruno Haible <bruno@clisp.org>, 2009.
   5 
   6    This file is free software.
   7    It is dual-licensed under "the GNU LGPLv3+ or the GNU GPLv2+".
   8    You can redistribute it and/or modify it under either
   9      - the terms of the GNU Lesser General Public License as published
  10        by the Free Software Foundation; either version 3, or (at your
  11        option) any later version, or
  12      - the terms of the GNU General Public License as published by the
  13        Free Software Foundation; either version 2, or (at your option)
  14        any later version, or
  15      - the same dual license "the GNU LGPLv3+ or the GNU GPLv2+".
  16 
  17    This file is distributed in the hope that it will be useful,
  18    but WITHOUT ANY WARRANTY; without even the implied warranty of
  19    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  20    Lesser General Public License and the GNU General Public License
  21    for more details.
  22 
  23    You should have received a copy of the GNU Lesser General Public
  24    License and of the GNU General Public License along with this
  25    program.  If not, see <https://www.gnu.org/licenses/>.  */
  26 
  27 int
  28 FUNC (const UNIT *s1, const UNIT *s2)
     /*  */
  29 {
  30   /* When this function succeeds, it sets errno back to its original value.
  31      When it fails, it sets errno, but also returns a meaningful return value,
  32      for the sake of callers which ignore errno.  */
  33   int final_errno = errno;
  34   const char *encoding = locale_charset ();
  35   char *sl1;
  36   char *sl2;
  37   int result;
  38 
  39   /* Pass iconveh_error here, not iconveh_question_mark.  Otherwise the
  40      conversion to locale encoding can do transliteration or map some
  41      characters to question marks, leading to results that depend on the
  42      iconv() implementation and are not obvious.  */
  43   sl1 = U_STRCONV_TO_ENCODING (s1, encoding, iconveh_error);
  44   if (sl1 != NULL)
  45     {
  46       sl2 = U_STRCONV_TO_ENCODING (s2, encoding, iconveh_error);
  47       if (sl2 != NULL)
  48         {
  49           /* Compare sl1 and sl2.  */
  50           errno = 0;
  51           result = strcoll (sl1, sl2);
  52           if (errno == 0)
  53             {
  54               /* strcoll succeeded.  */
  55               free (sl1);
  56               free (sl2);
  57               /* The conversion to locale encoding can drop Unicode TAG
  58                  characters.  Therefore sl1 and sl2 may be equal when s1
  59                  and s2 were in fact different.  Return a nonzero result
  60                  in this case.  */
  61               if (result == 0)
  62                 result = U_STRCMP (s1, s2);
  63             }
  64           else
  65             {
  66               /* strcoll failed.  */
  67               final_errno = errno;
  68               free (sl1);
  69               free (sl2);
  70               result = U_STRCMP (s1, s2);
  71             }
  72         }
  73       else
  74         {
  75           /* s1 could be converted to locale encoding, s2 not.  */
  76           final_errno = errno;
  77           free (sl1);
  78           result = -1;
  79         }
  80     }
  81   else
  82     {
  83       final_errno = errno;
  84       sl2 = U_STRCONV_TO_ENCODING (s2, encoding, iconveh_error);
  85       if (sl2 != NULL)
  86         {
  87           /* s2 could be converted to locale encoding, s1 not.  */
  88           free (sl2);
  89           result = 1;
  90         }
  91       else
  92         {
  93           /* Neither s1 nor s2 could be converted to locale encoding.  */
  94           result = U_STRCMP (s1, s2);
  95         }
  96     }
  97 
  98   errno = final_errno;
  99   return result;
 100 }

/* */