ios_base.h

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// Iostreams base classes -*- C++ -*-

// Copyright (C) 1997-2013 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library.  This library 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; either version 3, or (at your option)
// any later version.

// This library 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.

// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.

// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
// <http://www.gnu.org/licenses/>.

//
// ISO C++ 14882: 27.4  Iostreams base classes
//

#ifndef _IOS_BASE_H
#define _IOS_BASE_H 1

#pragma GCC system_header

#include <ext/atomicity.h>
#include <bits/localefwd.h>
#include <bits/locale_classes.h>

namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION

  // The following definitions of bitmask types are enums, not ints,
  // as permitted (but not required) in the standard, in order to provide
  // better type safety in iostream calls.  A side effect is that
  // expressions involving them are no longer compile-time constants.
  enum _Ios_Fmtflags 
    { 
      _S_boolalpha  = 1L << 0,
      _S_dec        = 1L << 1,
      _S_fixed      = 1L << 2,
      _S_hex        = 1L << 3,
      _S_internal   = 1L << 4,
      _S_left       = 1L << 5,
      _S_oct        = 1L << 6,
      _S_right      = 1L << 7,
      _S_scientific     = 1L << 8,
      _S_showbase   = 1L << 9,
      _S_showpoint  = 1L << 10,
      _S_showpos    = 1L << 11,
      _S_skipws     = 1L << 12,
      _S_unitbuf    = 1L << 13,
      _S_uppercase  = 1L << 14,
      _S_adjustfield    = _S_left | _S_right | _S_internal,
      _S_basefield  = _S_dec | _S_oct | _S_hex,
      _S_floatfield     = _S_scientific | _S_fixed,
      _S_ios_fmtflags_end = 1L << 16,
      _S_ios_fmtflags_max = __INT_MAX__,
      _S_ios_fmtflags_min = ~__INT_MAX__
    };

  inline _GLIBCXX_CONSTEXPR _Ios_Fmtflags
  operator&(_Ios_Fmtflags __a, _Ios_Fmtflags __b)
  { return _Ios_Fmtflags(static_cast<int>(__a) & static_cast<int>(__b)); }

  inline _GLIBCXX_CONSTEXPR _Ios_Fmtflags
  operator|(_Ios_Fmtflags __a, _Ios_Fmtflags __b)
  { return _Ios_Fmtflags(static_cast<int>(__a) | static_cast<int>(__b)); }

  inline _GLIBCXX_CONSTEXPR _Ios_Fmtflags
  operator^(_Ios_Fmtflags __a, _Ios_Fmtflags __b)
  { return _Ios_Fmtflags(static_cast<int>(__a) ^ static_cast<int>(__b)); }

  inline _GLIBCXX_CONSTEXPR _Ios_Fmtflags
  operator~(_Ios_Fmtflags __a)
  { return _Ios_Fmtflags(~static_cast<int>(__a)); }

  inline const _Ios_Fmtflags&
  operator|=(_Ios_Fmtflags& __a, _Ios_Fmtflags __b)
  { return __a = __a | __b; }

  inline const _Ios_Fmtflags&
  operator&=(_Ios_Fmtflags& __a, _Ios_Fmtflags __b)
  { return __a = __a & __b; }

  inline const _Ios_Fmtflags&
  operator^=(_Ios_Fmtflags& __a, _Ios_Fmtflags __b)
  { return __a = __a ^ __b; }


  enum _Ios_Openmode 
    { 
      _S_app        = 1L << 0,
      _S_ate        = 1L << 1,
      _S_bin        = 1L << 2,
      _S_in         = 1L << 3,
      _S_out        = 1L << 4,
      _S_trunc      = 1L << 5,
      _S_ios_openmode_end = 1L << 16,
      _S_ios_openmode_max = __INT_MAX__,
      _S_ios_openmode_min = ~__INT_MAX__
    };

  inline _GLIBCXX_CONSTEXPR _Ios_Openmode
  operator&(_Ios_Openmode __a, _Ios_Openmode __b)
  { return _Ios_Openmode(static_cast<int>(__a) & static_cast<int>(__b)); }

  inline _GLIBCXX_CONSTEXPR _Ios_Openmode
  operator|(_Ios_Openmode __a, _Ios_Openmode __b)
  { return _Ios_Openmode(static_cast<int>(__a) | static_cast<int>(__b)); }

  inline _GLIBCXX_CONSTEXPR _Ios_Openmode
  operator^(_Ios_Openmode __a, _Ios_Openmode __b)
  { return _Ios_Openmode(static_cast<int>(__a) ^ static_cast<int>(__b)); }

  inline _GLIBCXX_CONSTEXPR _Ios_Openmode
  operator~(_Ios_Openmode __a)
  { return _Ios_Openmode(~static_cast<int>(__a)); }

  inline const _Ios_Openmode&
  operator|=(_Ios_Openmode& __a, _Ios_Openmode __b)
  { return __a = __a | __b; }

  inline const _Ios_Openmode&
  operator&=(_Ios_Openmode& __a, _Ios_Openmode __b)
  { return __a = __a & __b; }

  inline const _Ios_Openmode&
  operator^=(_Ios_Openmode& __a, _Ios_Openmode __b)
  { return __a = __a ^ __b; }


  enum _Ios_Iostate
    { 
      _S_goodbit        = 0,
      _S_badbit         = 1L << 0,
      _S_eofbit         = 1L << 1,
      _S_failbit        = 1L << 2,
      _S_ios_iostate_end = 1L << 16,
      _S_ios_iostate_max = __INT_MAX__,
      _S_ios_iostate_min = ~__INT_MAX__
    };

  inline _GLIBCXX_CONSTEXPR _Ios_Iostate
  operator&(_Ios_Iostate __a, _Ios_Iostate __b)
  { return _Ios_Iostate(static_cast<int>(__a) & static_cast<int>(__b)); }

  inline _GLIBCXX_CONSTEXPR _Ios_Iostate
  operator|(_Ios_Iostate __a, _Ios_Iostate __b)
  { return _Ios_Iostate(static_cast<int>(__a) | static_cast<int>(__b)); }

  inline _GLIBCXX_CONSTEXPR _Ios_Iostate
  operator^(_Ios_Iostate __a, _Ios_Iostate __b)
  { return _Ios_Iostate(static_cast<int>(__a) ^ static_cast<int>(__b)); }

  inline _GLIBCXX_CONSTEXPR _Ios_Iostate
  operator~(_Ios_Iostate __a)
  { return _Ios_Iostate(~static_cast<int>(__a)); }

  inline const _Ios_Iostate&
  operator|=(_Ios_Iostate& __a, _Ios_Iostate __b)
  { return __a = __a | __b; }

  inline const _Ios_Iostate&
  operator&=(_Ios_Iostate& __a, _Ios_Iostate __b)
  { return __a = __a & __b; }

  inline const  _Ios_Iostate&
  operator^=(_Ios_Iostate& __a, _Ios_Iostate __b)
  { return __a = __a ^ __b; }


  enum _Ios_Seekdir 
    { 
      _S_beg = 0,
      _S_cur = _GLIBCXX_STDIO_SEEK_CUR,
      _S_end = _GLIBCXX_STDIO_SEEK_END,
      _S_ios_seekdir_end = 1L << 16 
    };

  // 27.4.2  Class ios_base
  class ios_base
  {
  public:

    class failure : public exception
    {
    public:
      // _GLIBCXX_RESOLVE_LIB_DEFECTS
      // 48.  Use of non-existent exception constructor
      explicit
      failure(const string& __str) throw();

      // This declaration is not useless:
      // http://gcc.gnu.org/onlinedocs/gcc-4.3.2/gcc/Vague-Linkage.html
      virtual
      ~failure() throw();

      virtual const char*
      what() const throw();

    private:
      string _M_msg;
    };

    // 27.4.2.1.2  Type ios_base::fmtflags
    typedef _Ios_Fmtflags fmtflags;

    static const fmtflags boolalpha =   _S_boolalpha;

    static const fmtflags dec =         _S_dec;

    static const fmtflags fixed =       _S_fixed;

    static const fmtflags hex =         _S_hex;

    static const fmtflags internal =    _S_internal;

    static const fmtflags left =        _S_left;

    static const fmtflags oct =         _S_oct;

    static const fmtflags right =       _S_right;

    static const fmtflags scientific =  _S_scientific;

    static const fmtflags showbase =    _S_showbase;

    static const fmtflags showpoint =   _S_showpoint;

    static const fmtflags showpos =     _S_showpos;

    static const fmtflags skipws =      _S_skipws;

    static const fmtflags unitbuf =     _S_unitbuf;

    static const fmtflags uppercase =   _S_uppercase;

    static const fmtflags adjustfield = _S_adjustfield;

    static const fmtflags basefield =   _S_basefield;

    static const fmtflags floatfield =  _S_floatfield;

    // 27.4.2.1.3  Type ios_base::iostate
    typedef _Ios_Iostate iostate;

    static const iostate badbit =   _S_badbit;

    static const iostate eofbit =   _S_eofbit;

    static const iostate failbit =  _S_failbit;

    static const iostate goodbit =  _S_goodbit;

    // 27.4.2.1.4  Type ios_base::openmode
    typedef _Ios_Openmode openmode;

    static const openmode app =     _S_app;

    static const openmode ate =     _S_ate;

    static const openmode binary =  _S_bin;

    static const openmode in =      _S_in;

    static const openmode out =     _S_out;

    static const openmode trunc =   _S_trunc;

    // 27.4.2.1.5  Type ios_base::seekdir
    typedef _Ios_Seekdir seekdir;

    static const seekdir beg =      _S_beg;

    static const seekdir cur =      _S_cur;

    static const seekdir end =      _S_end;

    // Annex D.6
    typedef int io_state;
    typedef int open_mode;
    typedef int seek_dir;

    typedef std::streampos streampos;
    typedef std::streamoff streamoff;

    // Callbacks;
    enum event
    {
      erase_event,
      imbue_event,
      copyfmt_event
    };

    typedef void (*event_callback) (event __e, ios_base& __b, int __i);

    void
    register_callback(event_callback __fn, int __index);

  protected:
    streamsize      _M_precision;
    streamsize      _M_width;
    fmtflags        _M_flags;
    iostate     _M_exception;
    iostate     _M_streambuf_state;

    // 27.4.2.6  Members for callbacks
    // 27.4.2.6  ios_base callbacks
    struct _Callback_list
    {
      // Data Members
      _Callback_list*       _M_next;
      ios_base::event_callback  _M_fn;
      int           _M_index;
      _Atomic_word      _M_refcount;  // 0 means one reference.

      _Callback_list(ios_base::event_callback __fn, int __index,
             _Callback_list* __cb)
      : _M_next(__cb), _M_fn(__fn), _M_index(__index), _M_refcount(0) { }

      void
      _M_add_reference() { __gnu_cxx::__atomic_add_dispatch(&_M_refcount, 1); }

      // 0 => OK to delete.
      int
      _M_remove_reference() 
      {
        // Be race-detector-friendly.  For more info see bits/c++config.
        _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE(&_M_refcount);
        int __res = __gnu_cxx::__exchange_and_add_dispatch(&_M_refcount, -1);
        if (__res == 0)
          {
            _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER(&_M_refcount);
          }
        return __res;
      }
    };

     _Callback_list*    _M_callbacks;

    void
    _M_call_callbacks(event __ev) throw();

    void
    _M_dispose_callbacks(void) throw();

    // 27.4.2.5  Members for iword/pword storage
    struct _Words
    {
      void* _M_pword;
      long  _M_iword;
      _Words() : _M_pword(0), _M_iword(0) { }
    };

    // Only for failed iword/pword calls.
    _Words      _M_word_zero;

    // Guaranteed storage.
    // The first 5 iword and pword slots are reserved for internal use.
    enum { _S_local_word_size = 8 };
    _Words      _M_local_word[_S_local_word_size];

    // Allocated storage.
    int         _M_word_size;
    _Words*     _M_word;

    _Words&
    _M_grow_words(int __index, bool __iword);

    // Members for locale and locale caching.
    locale      _M_ios_locale;

    void
    _M_init() throw();

  public:

    // 27.4.2.1.6  Class ios_base::Init
    // Used to initialize standard streams. In theory, g++ could use
    // -finit-priority to order this stuff correctly without going
    // through these machinations.
    class Init
    {
      friend class ios_base;
    public:
      Init();
      ~Init();

    private:
      static _Atomic_word   _S_refcount;
      static bool       _S_synced_with_stdio;
    };

    // [27.4.2.2] fmtflags state functions
    fmtflags
    flags() const
    { return _M_flags; }

    fmtflags
    flags(fmtflags __fmtfl)
    {
      fmtflags __old = _M_flags;
      _M_flags = __fmtfl;
      return __old;
    }

    fmtflags
    setf(fmtflags __fmtfl)
    {
      fmtflags __old = _M_flags;
      _M_flags |= __fmtfl;
      return __old;
    }

    fmtflags
    setf(fmtflags __fmtfl, fmtflags __mask)
    {
      fmtflags __old = _M_flags;
      _M_flags &= ~__mask;
      _M_flags |= (__fmtfl & __mask);
      return __old;
    }

    void
    unsetf(fmtflags __mask)
    { _M_flags &= ~__mask; }

    streamsize
    precision() const
    { return _M_precision; }

    streamsize
    precision(streamsize __prec)
    {
      streamsize __old = _M_precision;
      _M_precision = __prec;
      return __old;
    }

    streamsize
    width() const
    { return _M_width; }

    streamsize
    width(streamsize __wide)
    {
      streamsize __old = _M_width;
      _M_width = __wide;
      return __old;
    }

    // [27.4.2.4] ios_base static members
    static bool
    sync_with_stdio(bool __sync = true);

    // [27.4.2.3] ios_base locale functions
    locale
    imbue(const locale& __loc) throw();

    locale
    getloc() const
    { return _M_ios_locale; }

    const locale&
    _M_getloc() const
    { return _M_ios_locale; }

    // [27.4.2.5] ios_base storage functions
    static int
    xalloc() throw();

    long&
    iword(int __ix)
    {
      _Words& __word = (__ix < _M_word_size)
            ? _M_word[__ix] : _M_grow_words(__ix, true);
      return __word._M_iword;
    }

    void*&
    pword(int __ix)
    {
      _Words& __word = (__ix < _M_word_size)
            ? _M_word[__ix] : _M_grow_words(__ix, false);
      return __word._M_pword;
    }

    // Destructor
    virtual ~ios_base();

  protected:
    ios_base() throw ();

  // _GLIBCXX_RESOLVE_LIB_DEFECTS
  // 50.  Copy constructor and assignment operator of ios_base
  private:
    ios_base(const ios_base&);

    ios_base&
    operator=(const ios_base&);
  };

  // [27.4.5.1] fmtflags manipulators
  inline ios_base&
  boolalpha(ios_base& __base)
  {
    __base.setf(ios_base::boolalpha);
    return __base;
  }

  inline ios_base&
  noboolalpha(ios_base& __base)
  {
    __base.unsetf(ios_base::boolalpha);
    return __base;
  }

  inline ios_base&
  showbase(ios_base& __base)
  {
    __base.setf(ios_base::showbase);
    return __base;
  }

  inline ios_base&
  noshowbase(ios_base& __base)
  {
    __base.unsetf(ios_base::showbase);
    return __base;
  }

  inline ios_base&
  showpoint(ios_base& __base)
  {
    __base.setf(ios_base::showpoint);
    return __base;
  }

  inline ios_base&
  noshowpoint(ios_base& __base)
  {
    __base.unsetf(ios_base::showpoint);
    return __base;
  }

  inline ios_base&
  showpos(ios_base& __base)
  {
    __base.setf(ios_base::showpos);
    return __base;
  }

  inline ios_base&
  noshowpos(ios_base& __base)
  {
    __base.unsetf(ios_base::showpos);
    return __base;
  }

  inline ios_base&
  skipws(ios_base& __base)
  {
    __base.setf(ios_base::skipws);
    return __base;
  }

  inline ios_base&
  noskipws(ios_base& __base)
  {
    __base.unsetf(ios_base::skipws);
    return __base;
  }

  inline ios_base&
  uppercase(ios_base& __base)
  {
    __base.setf(ios_base::uppercase);
    return __base;
  }

  inline ios_base&
  nouppercase(ios_base& __base)
  {
    __base.unsetf(ios_base::uppercase);
    return __base;
  }

  inline ios_base&
  unitbuf(ios_base& __base)
  {
     __base.setf(ios_base::unitbuf);
     return __base;
  }

  inline ios_base&
  nounitbuf(ios_base& __base)
  {
     __base.unsetf(ios_base::unitbuf);
     return __base;
  }

  // [27.4.5.2] adjustfield manipulators
  inline ios_base&
  internal(ios_base& __base)
  {
     __base.setf(ios_base::internal, ios_base::adjustfield);
     return __base;
  }

  inline ios_base&
  left(ios_base& __base)
  {
    __base.setf(ios_base::left, ios_base::adjustfield);
    return __base;
  }

  inline ios_base&
  right(ios_base& __base)
  {
    __base.setf(ios_base::right, ios_base::adjustfield);
    return __base;
  }

  // [27.4.5.3] basefield manipulators
  inline ios_base&
  dec(ios_base& __base)
  {
    __base.setf(ios_base::dec, ios_base::basefield);
    return __base;
  }

  inline ios_base&
  hex(ios_base& __base)
  {
    __base.setf(ios_base::hex, ios_base::basefield);
    return __base;
  }

  inline ios_base&
  oct(ios_base& __base)
  {
    __base.setf(ios_base::oct, ios_base::basefield);
    return __base;
  }

  // [27.4.5.4] floatfield manipulators
  inline ios_base&
  fixed(ios_base& __base)
  {
    __base.setf(ios_base::fixed, ios_base::floatfield);
    return __base;
  }

  inline ios_base&
  scientific(ios_base& __base)
  {
    __base.setf(ios_base::scientific, ios_base::floatfield);
    return __base;
  }

_GLIBCXX_END_NAMESPACE_VERSION
} // namespace

#endif /* _IOS_BASE_H */