/**********************************************************************

locale.cpp - Handle internal numeric locale issues -- parse data in "C"

Copyright (C) 2008 by Geoffrey R. Hutchison

This file is part of the Open Babel project.

For more information, see <http://openbabel.org/>

This program is free software; you can redistribute it and/or modify

it under the terms of the GNU General Public License as published by

the Free Software Foundation version 2 of the License.

This program is distributed in the hope that it will be useful,

but WITHOUT ANY WARRANTY; without even the implied warranty of

MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

GNU General Public License for more details.

***********************************************************************/

#include <cstdlib>

#include <cstring>

#include <openbabel/locale.h>

#if HAVE_XLOCALE_H

#include <xlocale.h>

#endif

#if HAVE_LOCALE_H

#include <locale.h>

#endif

namespace OpenBabel

{

  class OBLocalePrivate {

  public:

    char *old_locale_string;

#if HAVE_USELOCALE

    locale_t new_c_num_locale;

    locale_t old_locale;

#endif

    unsigned int counter; // Reference counter -- ensures balance in SetLocale/RestoreLocale calls

    OBLocalePrivate(): counter(0)

    {

#if HAVE_USELOCALE

      new_c_num_locale = newlocale(LC_NUMERIC_MASK, NULL, NULL);

#endif

    }

    ~OBLocalePrivate()

    {    }

  }; // class definition for OBLocalePrivate

  /** \class OBLocale locale.h <openbabel/locale.h>

   *

   * Many users will utilize Open Babel and tools built on top of the library

   * in non-English locales. In particular, the numeric locale (LC_NUMERIC)

   * is used to determine the parsing of numeric data in files, reference data,

   * etc.

   *

   * The OBLocale class, and its global variable obLocale handle both internal

   * parsing of data through the ANSI-C numeric locale and can be used for

   * external use as well.

   *

   * In particular, where available, OBLocale will use the enhanced uselocale()

   * interface, which sets the locale for a particular thread, rather

   * for the entire process. (This is available on Linux, Mac OS X,

   * and other platforms.)

   *

   * \code

   * obLocale.SetLocale(); // set the numeric locale before reading data

   * ... // your data processing here

   * obLocale.RestoreLocale(); // restore the numeric locale

   * \endcode

   *

   * To prevent errors, OBLocale will handle reference counting.

   * If nested function calls all set the locale, only the first call

   * to SetLocale() and the last call to RestoreLocale() will do any work.

   **/

  OBLocale::OBLocale()

  {

    d = new OBLocalePrivate;

  }

  OBLocale::~OBLocale()

  {

    if (d) {

      delete d;

      d = nullptr;

    }

  }

  void OBLocale::SetLocale()

  {

    if (d->counter == 0) {

      // Set the locale for number parsing to avoid locale issues: PR#1785463

#if HAVE_USELOCALE

      // Extended per-thread interface

      d->old_locale = uselocale(d->new_c_num_locale);

#else

#ifndef ANDROID

      // Original global POSIX interface

      // regular UNIX, no USELOCALE, no ANDROID

      d->old_locale_string = strdup(setlocale(LC_NUMERIC, nullptr));

#else

      // ANDROID should stay as "C" -- Igor Filippov

      d->old_locale_string = "C";

#endif

      setlocale(LC_NUMERIC, "C");

#endif

    }

    ++d->counter;

  }

  void OBLocale::RestoreLocale()

  {

    --d->counter;

    if(d->counter == 0) {

      // return the locale to the original one

#ifdef HAVE_USELOCALE

      uselocale(d->old_locale);

#else

      setlocale(LC_NUMERIC, d->old_locale_string);

#ifndef ANDROID

      // Don't free on Android because "C" is a static ctring constant

      free (d->old_locale_string);

#endif

#endif

    }

  }

  //global definitions

  // Global OBLocale for setting and restoring locale information

  OBLocale   obLocale;

} // namespace OpenBabel

//! \file locale.cpp

//! \brief Handle internal numeric locale issues -- parse data in "C"