RE: [PATCH] codecvt<wchar_t, char, mbstate_t>

[Pétur Runólfsson <peturr02 at ru dot is>]

Hi,

> Perhaps we need to scan the list of installed locales to find
> something with the needed charset (these tests only depend on
> the charset used by the locale, the language doesn't matter).

This seems to work, and doesn't depend on named locales working:

bool is_locale_available(const char* s)
{
  bool ret = false;
  const char* orig = std::setlocale(LC_ALL, NULL);
  char* saved = new char[std::strlen(orig) + 1];
  std::strcpy(saved, orig);

  if (std::setlocale(LC_ALL, s))
    ret = true;

  std::setlocale(LC_ALL, saved);
  delete [] saved;
  return ret;
}

std::locale create_locale_from_charset(const char* s)
{
  const char* const languages[] = {
    "da_DK",
    "de_DE",
    "en_AU", "en_GB", "en_HK", "en_IE", "en_US",
    "es_AR", "es_ES", "es_MX",
    "fi_FI",
    "fr_BE", "fr_CA", "fr_CH", "fr_FR", "fr_LU",
    "is_IS",
    "it_CH", "it_IT",
    "ja_JP",
    "nn_NO",
    "no_NO",
    "pt_BR", "pt_PT",
    "ru_RU", "ru_UA",
    "sv_FI", "sv_SE",
    "zh_CN", "zh_HK", "zh_SG", "zh_TW"
  };

  int buflen = std::strlen("aa_AA.") +
    std::strlen(s) +
    std::strlen("@euro") + 1;
  char* buffer = new char[buflen];

  const int n = sizeof(languages) / sizeof(languages[0]);
  for (int i = 0; i < n; ++i)
    {
      std::strcpy(buffer, languages[i]);
      std::strcat(buffer, ".");
      std::strcat(buffer, s);

      if (!is_locale_available(buffer))
	{
	  std::strcat(buffer, "@euro");
	  if (!is_locale_available(buffer))
	    continue;
	}

      std::locale loc (buffer);
      delete [] buffer;
      return loc;
    }

  delete [] buffer;
  std::printf("Could not find any locale for charset %s, bailing out\n", s);
  std::exit(1);
}

The codecvt testsuite can then use:

locale loc (create_locale_from_charset("ISO-8859-15"));

instead of

locale loc ("en_US.ISO-8859-15");

And for the rest of the testsuite, this generates a useful log
message when a locale needed by a testsuite is missing:

std::locale create_named_locale(const char* s)
{
  if (!is_locale_available(s))
    {
      std::printf("Locale %s is not available, bailing out\n", s);
      std::exit(1);
    }
  return std::locale(s);
}

Petur