1  /* Dispatching based on the current locale's character encoding.
       2     Copyright (C) 2018-2023 Free Software Foundation, Inc.
       3  
       4     This file is free software: you can redistribute it and/or modify
       5     it under the terms of the GNU Lesser General Public License as
       6     published by the Free Software Foundation; either version 2.1 of the
       7     License, or (at your option) any later version.
       8  
       9     This file 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
      12     GNU Lesser General Public License for more details.
      13  
      14     You should have received a copy of the GNU Lesser General Public License
      15     along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
      16  
      17  /* Written by Bruno Haible <bruno@clisp.org>, 2018.  */
      18  
      19  #include <config.h>
      20  
      21  /* Specification.  */
      22  #include "lc-charset-dispatch.h"
      23  
      24  #if GNULIB_defined_mbstate_t
      25  
      26  # include "localcharset.h"
      27  # include "streq.h"
      28  
      29  # if GNULIB_WCHAR_SINGLE_LOCALE
      30  /* When we know that the locale does not change, provide a speedup by
      31     caching the value of locale_encoding_classification.  */
      32  #  define locale_encoding_classification_cached locale_encoding_classification
      33  # else
      34  /* By default, don't make assumptions, hence no caching.  */
      35  #  define locale_encoding_classification_uncached locale_encoding_classification
      36  # endif
      37  
      38  # if GNULIB_WCHAR_SINGLE_LOCALE
      39  static inline
      40  # endif
      41  enc_t
      42  locale_encoding_classification_uncached (void)
      43  {
      44    const char *encoding = locale_charset ();
      45    if (STREQ_OPT (encoding, "UTF-8", 'U', 'T', 'F', '-', '8', 0, 0, 0, 0))
      46      return enc_utf8;
      47    if (STREQ_OPT (encoding, "EUC-JP", 'E', 'U', 'C', '-', 'J', 'P', 0, 0, 0))
      48      return enc_eucjp;
      49    if (STREQ_OPT (encoding, "EUC-KR", 'E', 'U', 'C', '-', 'K', 'R', 0, 0, 0)
      50        || STREQ_OPT (encoding, "GB2312", 'G', 'B', '2', '3', '1', '2', 0, 0, 0)
      51        || STREQ_OPT (encoding, "BIG5", 'B', 'I', 'G', '5', 0, 0, 0, 0, 0))
      52      return enc_94;
      53    if (STREQ_OPT (encoding, "EUC-TW", 'E', 'U', 'C', '-', 'T', 'W', 0, 0, 0))
      54      return enc_euctw;
      55    if (STREQ_OPT (encoding, "GB18030", 'G', 'B', '1', '8', '0', '3', '0', 0, 0))
      56      return enc_gb18030;
      57    if (STREQ_OPT (encoding, "SJIS", 'S', 'J', 'I', 'S', 0, 0, 0, 0, 0))
      58      return enc_sjis;
      59    return enc_other;
      60  }
      61  
      62  # if GNULIB_WCHAR_SINGLE_LOCALE
      63  
      64  static int cached_locale_enc = -1;
      65  
      66  enc_t
      67  locale_encoding_classification_cached (void)
      68  {
      69    if (cached_locale_enc < 0)
      70      cached_locale_enc = locale_encoding_classification_uncached ();
      71    return cached_locale_enc;
      72  }
      73  
      74  # endif
      75  
      76  #else
      77  
      78  /* This declaration is solely to ensure that after preprocessing
      79     this file is never empty.  */
      80  typedef int dummy;
      81  
      82  #endif