C++ “ostream“

ostream.hpp

// Output streams -*- C++ -*-

// Copyright (C) 1997-2021 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
// .



//
// ISO C++ 14882: 27.6.2  Output streams
//

#ifndef _GLIBCXX_OSTREAM
#define _GLIBCXX_OSTREAM 1

#pragma GCC system_header

#include 
#include 

namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION

  
  template
    class basic_ostream : virtual public basic_ios<_CharT, _Traits>
    {
    public:
      // Types (inherited from basic_ios):
      typedef _CharT			 		char_type;
      typedef typename _Traits::int_type 		int_type;
      typedef typename _Traits::pos_type 		pos_type;
      typedef typename _Traits::off_type 		off_type;
      typedef _Traits			 		traits_type;

      // Non-standard Types:
      typedef basic_streambuf<_CharT, _Traits> 		__streambuf_type;
      typedef basic_ios<_CharT, _Traits>		__ios_type;
      typedef basic_ostream<_CharT, _Traits>		__ostream_type;
      typedef num_put<_CharT, ostreambuf_iterator<_CharT, _Traits> >
      							__num_put_type;
      typedef ctype<_CharT>	      			__ctype_type;

      
      explicit
      basic_ostream(__streambuf_type* __sb)
      { this->init(__sb); }

      
      virtual
      ~basic_ostream() { }

      /// Safe prefix/suffix operations.
      class sentry;
      friend class sentry;

      ///@{
      
      __ostream_type&
      operator<<(__ostream_type& (*__pf)(__ostream_type&))
      {
	// _GLIBCXX_RESOLVE_LIB_DEFECTS
	// DR 60. What is a formatted input function?
	// The inserters for manipulators are *not* formatted output functions.
	return __pf(*this);
      }

      __ostream_type&
      operator<<(__ios_type& (*__pf)(__ios_type&))
      {
	// _GLIBCXX_RESOLVE_LIB_DEFECTS
	// DR 60. What is a formatted input function?
	// The inserters for manipulators are *not* formatted output functions.
	__pf(*this);
	return *this;
      }

      __ostream_type&
      operator<<(ios_base& (*__pf) (ios_base&))
      {
	// _GLIBCXX_RESOLVE_LIB_DEFECTS
	// DR 60. What is a formatted input function?
	// The inserters for manipulators are *not* formatted output functions.
	__pf(*this);
	return *this;
      }
      ///@}

      ///@{
      

      ///@{
      
      __ostream_type&
      operator<<(long __n)
      { return _M_insert(__n); }

      __ostream_type&
      operator<<(unsigned long __n)
      { return _M_insert(__n); }

      __ostream_type&
      operator<<(bool __n)
      { return _M_insert(__n); }

      __ostream_type&
      operator<<(short __n);

      __ostream_type&
      operator<<(unsigned short __n)
      {
	// _GLIBCXX_RESOLVE_LIB_DEFECTS
	// 117. basic_ostream uses nonexistent num_put member functions.
	return _M_insert(static_cast(__n));
      }

      __ostream_type&
      operator<<(int __n);

      __ostream_type&
      operator<<(unsigned int __n)
      {
	// _GLIBCXX_RESOLVE_LIB_DEFECTS
	// 117. basic_ostream uses nonexistent num_put member functions.
	return _M_insert(static_cast(__n));
      }

#ifdef _GLIBCXX_USE_LONG_LONG
      __ostream_type&
      operator<<(long long __n)
      { return _M_insert(__n); }

      __ostream_type&
      operator<<(unsigned long long __n)
      { return _M_insert(__n); }
#endif
      ///@}

      ///@{
      
      __ostream_type&
      operator<<(double __f)
      { return _M_insert(__f); }

      __ostream_type&
      operator<<(float __f)
      {
	// _GLIBCXX_RESOLVE_LIB_DEFECTS
	// 117. basic_ostream uses nonexistent num_put member functions.
	return _M_insert(static_cast(__f));
      }

      __ostream_type&
      operator<<(long double __f)
      { return _M_insert(__f); }
      ///@}

      
      __ostream_type&
      operator<<(const void* __p)
      { return _M_insert(__p); }

#if __cplusplus >= 201703L
      __ostream_type&
      operator<<(nullptr_t)
      { return *this << "nullptr"; }
#endif

      
      __ostream_type&
      operator<<(__streambuf_type* __sb);
      ///@}

      ///@{
      

      
      __ostream_type&
      put(char_type __c);

      
      void
      _M_write(const char_type* __s, streamsize __n)
      {
	const streamsize __put = this->rdbuf()->sputn(__s, __n);
	if (__put != __n)
	  this->setstate(ios_base::badbit);
      }

      
      __ostream_type&
      write(const char_type* __s, streamsize __n);
      ///@}

      
      __ostream_type&
      flush();

      
      pos_type
      tellp();

      
      __ostream_type&
      seekp(pos_type);

      
       __ostream_type&
      seekp(off_type, ios_base::seekdir);

    protected:
      basic_ostream()
      { this->init(0); }

#if __cplusplus >= 201103L
      // Non-standard constructor that does not call init()
      basic_ostream(basic_iostream<_CharT, _Traits>&) { }

      basic_ostream(const basic_ostream&) = delete;

      basic_ostream(basic_ostream&& __rhs)
      : __ios_type()
      { __ios_type::move(__rhs); }

      // 27.7.3.3 Assign/swap

      basic_ostream& operator=(const basic_ostream&) = delete;

      basic_ostream&
      operator=(basic_ostream&& __rhs)
      {
	swap(__rhs);
	return *this;
      }

      void
      swap(basic_ostream& __rhs)
      { __ios_type::swap(__rhs); }
#endif

      template
	__ostream_type&
	_M_insert(_ValueT __v);
    };

  
  template 
    class basic_ostream<_CharT, _Traits>::sentry
    {
      // Data Members.
      bool 				_M_ok;
      basic_ostream<_CharT, _Traits>& 	_M_os;

    public:
      
      explicit
      sentry(basic_ostream<_CharT, _Traits>& __os);

#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
      
      ~sentry()
      {
	// XXX MT
	if (bool(_M_os.flags() & ios_base::unitbuf) && !uncaught_exception())
	  {
	    // Can't call flush directly or else will get into recursive lock.
	    if (_M_os.rdbuf() && _M_os.rdbuf()->pubsync() == -1)
	      _M_os.setstate(ios_base::badbit);
	  }
      }
#pragma GCC diagnostic pop

      
#if __cplusplus >= 201103L
      explicit
#endif
      operator bool() const
      { return _M_ok; }
    };

  ///@{
  
  template
    inline basic_ostream<_CharT, _Traits>&
    operator<<(basic_ostream<_CharT, _Traits>& ___out, _CharT __c)
    { return __ostream_insert(___out, &__c, 1); }

  template
    inline basic_ostream<_CharT, _Traits>&
    operator<<(basic_ostream<_CharT, _Traits>& ___out, char __c)
    { return (___out << ___out.widen(__c)); }

  // Specialization
  template
    inline basic_ostream&
    operator<<(basic_ostream& ___out, char __c)
    { return __ostream_insert(___out, &__c, 1); }

  // Signed and unsigned
  template
    inline basic_ostream&
    operator<<(basic_ostream& ___out, signed char __c)
    { return (___out << static_cast(__c)); }

  template
    inline basic_ostream&
    operator<<(basic_ostream& ___out, unsigned char __c)
    { return (___out << static_cast(__c)); }

#if __cplusplus > 201703L
  // The following deleted overloads prevent formatting character values as
  // numeric values.

#ifdef _GLIBCXX_USE_WCHAR_T
  template
    basic_ostream&
    operator<<(basic_ostream&, wchar_t) = delete;
#endif // _GLIBCXX_USE_WCHAR_T

#ifdef _GLIBCXX_USE_CHAR8_T
  template
    basic_ostream&
    operator<<(basic_ostream&, char8_t) = delete;
#endif

  template
    basic_ostream&
    operator<<(basic_ostream&, char16_t) = delete;

  template
    basic_ostream&
    operator<<(basic_ostream&, char32_t) = delete;

#ifdef _GLIBCXX_USE_WCHAR_T
#ifdef _GLIBCXX_USE_CHAR8_T
  template
    basic_ostream&
    operator<<(basic_ostream&, char8_t) = delete;
#endif // _GLIBCXX_USE_CHAR8_T

  template
    basic_ostream&
    operator<<(basic_ostream&, char16_t) = delete;

  template
    basic_ostream&
    operator<<(basic_ostream&, char32_t) = delete;
#endif // _GLIBCXX_USE_WCHAR_T
#endif // C++20
  ///@}

  ///@{
  
  template
    inline basic_ostream<_CharT, _Traits>&
    operator<<(basic_ostream<_CharT, _Traits>& ___out, const _CharT* __s)
    {
      if (!__s)
	___out.setstate(ios_base::badbit);
      else
	__ostream_insert(___out, __s,
			 static_cast(_Traits::length(__s)));
      return ___out;
    }

  template
    basic_ostream<_CharT, _Traits> &
    operator<<(basic_ostream<_CharT, _Traits>& ___out, const char* __s);

  // Partial specializations
  template
    inline basic_ostream&
    operator<<(basic_ostream& ___out, const char* __s)
    {
      if (!__s)
	___out.setstate(ios_base::badbit);
      else
	__ostream_insert(___out, __s,
			 static_cast(_Traits::length(__s)));
      return ___out;
    }

  // Signed and unsigned
  template
    inline basic_ostream&
    operator<<(basic_ostream& ___out, const signed char* __s)
    { return (___out << reinterpret_cast(__s)); }

  template
    inline basic_ostream &
    operator<<(basic_ostream& ___out, const unsigned char* __s)
    { return (___out << reinterpret_cast(__s)); }

#if __cplusplus > 201703L
   // The following deleted overloads prevent formatting strings as
   // pointer values.

#ifdef _GLIBCXX_USE_WCHAR_T
  template
    basic_ostream&
    operator<<(basic_ostream&, const wchar_t*) = delete;
#endif // _GLIBCXX_USE_WCHAR_T

#ifdef _GLIBCXX_USE_CHAR8_T
  template
    basic_ostream&
    operator<<(basic_ostream&, const char8_t*) = delete;
#endif // _GLIBCXX_USE_CHAR8_T

  template
    basic_ostream&
    operator<<(basic_ostream&, const char16_t*) = delete;

  template
    basic_ostream&
    operator<<(basic_ostream&, const char32_t*) = delete;

#ifdef _GLIBCXX_USE_WCHAR_T
#ifdef _GLIBCXX_USE_CHAR8_T
  template
    basic_ostream&
    operator<<(basic_ostream&, const char8_t*) = delete;
#endif

  template
    basic_ostream&
    operator<<(basic_ostream&, const char16_t*) = delete;

  template
    basic_ostream&
    operator<<(basic_ostream&, const char32_t*) = delete;
#endif // _GLIBCXX_USE_WCHAR_T
#endif // C++20
  ///@}

  // Standard basic_ostream manipulators

  
  template
    inline basic_ostream<_CharT, _Traits>&
    endl(basic_ostream<_CharT, _Traits>& __os)
    { return flush(__os.put(__os.widen('n'))); }

  
  template
    inline basic_ostream<_CharT, _Traits>&
    ends(basic_ostream<_CharT, _Traits>& __os)
    { return __os.put(_CharT()); }

  
  template
    inline basic_ostream<_CharT, _Traits>&
    flush(basic_ostream<_CharT, _Traits>& __os)
    { return __os.flush(); }

#if __cplusplus >= 201103L
  // C++11 27.7.3.9 Rvalue stream insertion [ostream.rvalue]
  // _GLIBCXX_RESOLVE_LIB_DEFECTS
  // 1203. More useful rvalue stream insertion

#if __cpp_lib_concepts
  // Use concepts if possible because they're cheaper to evaluate.
  template
    concept __derived_from_ios_base = is_class_v<_Tp>
      && (!is_same_v<_Tp, ios_base>)
      && requires (_Tp* __t, ios_base* __b) { __b = __t; };

  template
    requires __derived_from_ios_base<_Os>
      && requires (_Os& __os, const _Tp& __t) { __os << __t; }
    using __rvalue_stream_insertion_t = _Os&&;
#else
  template
    using _Require_derived_from_ios_base
      = _Require, __not_>,
		 is_convertible::type, ios_base*>>;

  template,
	   typename
	     = decltype(std::declval<_Os&>() << std::declval())>
    using __rvalue_stream_insertion_t = _Os&&;
#endif

  
  template
    inline __rvalue_stream_insertion_t<_Ostream, _Tp>
    operator<<(_Ostream&& __os, const _Tp& __x)
    {
      __os << __x;
      return std::move(__os);
    }

#if __cplusplus > 201703L && _GLIBCXX_USE_CXX11_ABI
  template
    class __syncbuf_base : public basic_streambuf<_CharT, _Traits>
    {
    public:
      static bool*
      _S_get(basic_streambuf<_CharT, _Traits>* __buf [[maybe_unused]]) noexcept
      {
#if __cpp_rtti
	if (auto __p = dynamic_cast<__syncbuf_base*>(__buf))
	  return &__p->_M_emit_on_sync;
#endif
	return nullptr;
      }

    protected:
      __syncbuf_base(basic_streambuf<_CharT, _Traits>* __w = nullptr)
      : _M_wrapped(__w)
      { }

      basic_streambuf<_CharT, _Traits>* _M_wrapped = nullptr;
      bool _M_emit_on_sync = false;
      bool _M_needs_sync = false;
    };

  template
    inline basic_ostream<_CharT, _Traits>&
    emit_on_flush(basic_ostream<_CharT, _Traits>& __os)
    {
      if (bool* __flag = __syncbuf_base<_CharT, _Traits>::_S_get(__os.rdbuf()))
	*__flag = true;
      return __os;
    }

  template
    inline basic_ostream<_CharT, _Traits>&
    noemit_on_flush(basic_ostream<_CharT, _Traits>& __os)
    {
      if (bool* __flag = __syncbuf_base<_CharT, _Traits>::_S_get(__os.rdbuf()))
	*__flag = false;
      return __os;
    }

  template
    inline basic_ostream<_CharT, _Traits>&
    flush_emit(basic_ostream<_CharT, _Traits>& __os)
    {
      struct _Restore
      {
	~_Restore() { *_M_flag = _M_prev; }

	bool _M_prev = false;
	bool* _M_flag = &_M_prev;
      } __restore;

      if (bool* __flag = __syncbuf_base<_CharT, _Traits>::_S_get(__os.rdbuf()))
	{
	  __restore._M_prev = *__flag;
	  __restore._M_flag = __flag;
	  *__flag = true;
	}

      __os.flush();
      return __os;
    }

#endif // C++20

#endif // C++11

_GLIBCXX_END_NAMESPACE_VERSION
} // namespace std

#include 

#endif