// String based streams -*- 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/>.
	
	/** @file include/sstream
	 *  This is a Standard C++ Library header.
	 */
	
	//
	// ISO C++ 14882: 27.7  String-based streams
	//
	
	#ifndef _GLIBCXX_SSTREAM
	#define _GLIBCXX_SSTREAM 1
	
	#pragma GCC system_header
	
	#include <istream>
	#include <ostream>
	
	namespace std _GLIBCXX_VISIBILITY(default)
	{
	_GLIBCXX_BEGIN_NAMESPACE_VERSION
	
	  // [27.7.1] template class basic_stringbuf
	  /**
	   *  @brief  The actual work of input and output (for std::string).
	   *  @ingroup io
	   *
	   *  @tparam _CharT  Type of character stream.
	   *  @tparam _Traits  Traits for character type, defaults to
	   *                   char_traits<_CharT>.
	   *  @tparam _Alloc  Allocator type, defaults to allocator<_CharT>.
	   *
	   *  This class associates either or both of its input and output sequences
	   *  with a sequence of characters, which can be initialized from, or made
	   *  available as, a @c std::basic_string.  (Paraphrased from [27.7.1]/1.)
	   *
	   *  For this class, open modes (of type @c ios_base::openmode) have
	   *  @c in set if the input sequence can be read, and @c out set if the
	   *  output sequence can be written.
	  */
	  template<typename _CharT, typename _Traits, typename _Alloc>
	    class basic_stringbuf : public basic_streambuf<_CharT, _Traits>
	    {
	    public:
	      // Types:
	      typedef _CharT 					char_type;
	      typedef _Traits 					traits_type;
	      // _GLIBCXX_RESOLVE_LIB_DEFECTS
	      // 251. basic_stringbuf missing allocator_type
	      typedef _Alloc				       	allocator_type;
	      typedef typename traits_type::int_type 		int_type;
	      typedef typename traits_type::pos_type 		pos_type;
	      typedef typename traits_type::off_type 		off_type;
	
	      typedef basic_streambuf<char_type, traits_type>  	__streambuf_type;
	      typedef basic_string<char_type, _Traits, _Alloc> 	__string_type;
	      typedef typename __string_type::size_type		__size_type;
	
	    protected:
	      /// Place to stash in || out || in | out settings for current stringbuf.
	      ios_base::openmode 	_M_mode;
	
	      // Data Members:
	      __string_type 		_M_string;
	
	    public:
	      // Constructors:
	      /**
	       *  @brief  Starts with an empty string buffer.
	       *  @param  __mode  Whether the buffer can read, or write, or both.
	       *
	       *  The default constructor initializes the parent class using its
	       *  own default ctor.
	      */
	      explicit
	      basic_stringbuf(ios_base::openmode __mode = ios_base::in | ios_base::out)
	      : __streambuf_type(), _M_mode(__mode), _M_string()
	      { }
	
	      /**
	       *  @brief  Starts with an existing string buffer.
	       *  @param  __str  A string to copy as a starting buffer.
	       *  @param  __mode  Whether the buffer can read, or write, or both.
	       *
	       *  This constructor initializes the parent class using its
	       *  own default ctor.
	      */
	      explicit
	      basic_stringbuf(const __string_type& __str,
			      ios_base::openmode __mode = ios_base::in | ios_base::out)
	      : __streambuf_type(), _M_mode(), _M_string(__str.data(), __str.size())
	      { _M_stringbuf_init(__mode); }
	
	      // Get and set:
	      /**
	       *  @brief  Copying out the string buffer.
	       *  @return  A copy of one of the underlying sequences.
	       *
	       *  <em>If the buffer is only created in input mode, the underlying
	       *  character sequence is equal to the input sequence; otherwise, it
	       *  is equal to the output sequence.</em> [27.7.1.2]/1
	      */
	      __string_type
	      str() const
	      {
		__string_type __ret;
		if (this->pptr())
		  {
		    // The current egptr() may not be the actual string end.
		    if (this->pptr() > this->egptr())
		      __ret = __string_type(this->pbase(), this->pptr());
		    else
	 	      __ret = __string_type(this->pbase(), this->egptr());
		  }
		else
		  __ret = _M_string;
		return __ret;
	      }
	
	      /**
	       *  @brief  Setting a new buffer.
	       *  @param  __s  The string to use as a new sequence.
	       *
	       *  Deallocates any previous stored sequence, then copies @a s to
	       *  use as a new one.
	      */
	      void
	      str(const __string_type& __s)
	      {
		// Cannot use _M_string = __s, since v3 strings are COW.
		_M_string.assign(__s.data(), __s.size());
		_M_stringbuf_init(_M_mode);
	      }
	
	    protected:
	      // Common initialization code goes here.
	      void
	      _M_stringbuf_init(ios_base::openmode __mode)
	      {
		_M_mode = __mode;
		__size_type __len = 0;
		if (_M_mode & (ios_base::ate | ios_base::app))
		  __len = _M_string.size();
		_M_sync(const_cast<char_type*>(_M_string.data()), 0, __len);
	      }
	
	      virtual streamsize
	      showmanyc()
	      { 
		streamsize __ret = -1;
		if (_M_mode & ios_base::in)
		  {
		    _M_update_egptr();
		    __ret = this->egptr() - this->gptr();
		  }
		return __ret;
	      }
	
	      virtual int_type
	      underflow();
	
	      virtual int_type
	      pbackfail(int_type __c = traits_type::eof());
	
	      virtual int_type
	      overflow(int_type __c = traits_type::eof());
	
	      /**
	       *  @brief  Manipulates the buffer.
	       *  @param  __s  Pointer to a buffer area.
	       *  @param  __n  Size of @a __s.
	       *  @return  @c this
	       *
	       *  If no buffer has already been created, and both @a __s and @a __n are
	       *  non-zero, then @c __s is used as a buffer; see
	       *  http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt11ch25s02.html
	       *  for more.
	      */
	      virtual __streambuf_type*
	      setbuf(char_type* __s, streamsize __n)
	      {
		if (__s && __n >= 0)
		  {
		    // This is implementation-defined behavior, and assumes
		    // that an external char_type array of length __n exists
		    // and has been pre-allocated. If this is not the case,
		    // things will quickly blow up.
		    
		    // Step 1: Destroy the current internal array.
		    _M_string.clear();
		    
		    // Step 2: Use the external array.
		    _M_sync(__s, __n, 0);
		  }
		return this;
	      }
	
	      virtual pos_type
	      seekoff(off_type __off, ios_base::seekdir __way,
		      ios_base::openmode __mode = ios_base::in | ios_base::out);
	
	      virtual pos_type
	      seekpos(pos_type __sp,
		      ios_base::openmode __mode = ios_base::in | ios_base::out);
	
	      // Internal function for correctly updating the internal buffer
	      // for a particular _M_string, due to initialization or re-sizing
	      // of an existing _M_string.
	      void
	      _M_sync(char_type* __base, __size_type __i, __size_type __o);
	
	      // Internal function for correctly updating egptr() to the actual
	      // string end.
	      void
	      _M_update_egptr()
	      {
		const bool __testin = _M_mode & ios_base::in;
		if (this->pptr() && this->pptr() > this->egptr())
		  {
		    if (__testin)
		      this->setg(this->eback(), this->gptr(), this->pptr());
		    else
		      this->setg(this->pptr(), this->pptr(), this->pptr());
		  }
	      }
	
	      // Works around the issue with pbump, part of the protected
	      // interface of basic_streambuf, taking just an int.
	      void
	      _M_pbump(char_type* __pbeg, char_type* __pend, off_type __off);
	    };
	
	
	  // [27.7.2] Template class basic_istringstream
	  /**
	   *  @brief  Controlling input for std::string.
	   *  @ingroup io
	   *
	   *  @tparam _CharT  Type of character stream.
	   *  @tparam _Traits  Traits for character type, defaults to
	   *                   char_traits<_CharT>.
	   *  @tparam _Alloc  Allocator type, defaults to allocator<_CharT>.
	   *
	   *  This class supports reading from objects of type std::basic_string,
	   *  using the inherited functions from std::basic_istream.  To control
	   *  the associated sequence, an instance of std::basic_stringbuf is used,
	   *  which this page refers to as @c sb.
	  */
	  template<typename _CharT, typename _Traits, typename _Alloc>
	    class basic_istringstream : public basic_istream<_CharT, _Traits>
	    {
	    public:
	      // Types:
	      typedef _CharT 					char_type;
	      typedef _Traits 					traits_type;
	      // _GLIBCXX_RESOLVE_LIB_DEFECTS
	      // 251. basic_stringbuf missing allocator_type
	      typedef _Alloc				       	allocator_type;
	      typedef typename traits_type::int_type 		int_type;
	      typedef typename traits_type::pos_type 		pos_type;
	      typedef typename traits_type::off_type 		off_type;
	
	      // Non-standard types:
	      typedef basic_string<_CharT, _Traits, _Alloc> 	__string_type;
	      typedef basic_stringbuf<_CharT, _Traits, _Alloc> 	__stringbuf_type;
	      typedef basic_istream<char_type, traits_type>	__istream_type;
	
	    private:
	      __stringbuf_type	_M_stringbuf;
	
	    public:
	      // Constructors:
	      /**
	       *  @brief  Default constructor starts with an empty string buffer.
	       *  @param  __mode  Whether the buffer can read, or write, or both.
	       *
	       *  @c ios_base::in is automatically included in @a __mode.
	       *
	       *  Initializes @c sb using @c __mode|in, and passes @c &sb to the base
	       *  class initializer.  Does not allocate any buffer.
	       *
	       *  That's a lie.  We initialize the base class with NULL, because the
	       *  string class does its own memory management.
	      */
	      explicit
	      basic_istringstream(ios_base::openmode __mode = ios_base::in)
	      : __istream_type(), _M_stringbuf(__mode | ios_base::in)
	      { this->init(&_M_stringbuf); }
	
	      /**
	       *  @brief  Starts with an existing string buffer.
	       *  @param  __str  A string to copy as a starting buffer.
	       *  @param  __mode  Whether the buffer can read, or write, or both.
	       *
	       *  @c ios_base::in is automatically included in @a mode.
	       *
	       *  Initializes @c sb using @a str and @c mode|in, and passes @c &sb
	       *  to the base class initializer.
	       *
	       *  That's a lie.  We initialize the base class with NULL, because the
	       *  string class does its own memory management.
	      */
	      explicit
	      basic_istringstream(const __string_type& __str,
				  ios_base::openmode __mode = ios_base::in)
	      : __istream_type(), _M_stringbuf(__str, __mode | ios_base::in)
	      { this->init(&_M_stringbuf); }
	
	      /**
	       *  @brief  The destructor does nothing.
	       *
	       *  The buffer is deallocated by the stringbuf object, not the
	       *  formatting stream.
	      */
	      ~basic_istringstream()
	      { }
	
	      // Members:
	      /**
	       *  @brief  Accessing the underlying buffer.
	       *  @return  The current basic_stringbuf buffer.
	       *
	       *  This hides both signatures of std::basic_ios::rdbuf().
	      */
	      __stringbuf_type*
	      rdbuf() const
	      { return const_cast<__stringbuf_type*>(&_M_stringbuf); }
	
	      /**
	       *  @brief  Copying out the string buffer.
	       *  @return  @c rdbuf()->str()
	      */
	      __string_type
	      str() const
	      { return _M_stringbuf.str(); }
	
	      /**
	       *  @brief  Setting a new buffer.
	       *  @param  __s  The string to use as a new sequence.
	       *
	       *  Calls @c rdbuf()->str(s).
	      */
	      void
	      str(const __string_type& __s)
	      { _M_stringbuf.str(__s); }
	    };
	
	
	  // [27.7.3] Template class basic_ostringstream
	  /**
	   *  @brief  Controlling output for std::string.
	   *  @ingroup io
	   *
	   *  @tparam _CharT  Type of character stream.
	   *  @tparam _Traits  Traits for character type, defaults to
	   *                   char_traits<_CharT>.
	   *  @tparam _Alloc  Allocator type, defaults to allocator<_CharT>.
	   *
	   *  This class supports writing to objects of type std::basic_string,
	   *  using the inherited functions from std::basic_ostream.  To control
	   *  the associated sequence, an instance of std::basic_stringbuf is used,
	   *  which this page refers to as @c sb.
	  */
	  template <typename _CharT, typename _Traits, typename _Alloc>
	    class basic_ostringstream : public basic_ostream<_CharT, _Traits>
	    {
	    public:
	      // Types:
	      typedef _CharT 					char_type;
	      typedef _Traits 					traits_type;
	      // _GLIBCXX_RESOLVE_LIB_DEFECTS
	      // 251. basic_stringbuf missing allocator_type
	      typedef _Alloc				       	allocator_type;
	      typedef typename traits_type::int_type 		int_type;
	      typedef typename traits_type::pos_type 		pos_type;
	      typedef typename traits_type::off_type 		off_type;
	
	      // Non-standard types:
	      typedef basic_string<_CharT, _Traits, _Alloc> 	__string_type;
	      typedef basic_stringbuf<_CharT, _Traits, _Alloc> 	__stringbuf_type;
	      typedef basic_ostream<char_type, traits_type>	__ostream_type;
	
	    private:
	      __stringbuf_type	_M_stringbuf;
	
	    public:
	      // Constructors/destructor:
	      /**
	       *  @brief  Default constructor starts with an empty string buffer.
	       *  @param  __mode  Whether the buffer can read, or write, or both.
	       *
	       *  @c ios_base::out is automatically included in @a mode.
	       *
	       *  Initializes @c sb using @c mode|out, and passes @c &sb to the base
	       *  class initializer.  Does not allocate any buffer.
	       *
	       *  That's a lie.  We initialize the base class with NULL, because the
	       *  string class does its own memory management.
	      */
	      explicit
	      basic_ostringstream(ios_base::openmode __mode = ios_base::out)
	      : __ostream_type(), _M_stringbuf(__mode | ios_base::out)
	      { this->init(&_M_stringbuf); }
	
	      /**
	       *  @brief  Starts with an existing string buffer.
	       *  @param  __str  A string to copy as a starting buffer.
	       *  @param  __mode  Whether the buffer can read, or write, or both.
	       *
	       *  @c ios_base::out is automatically included in @a mode.
	       *
	       *  Initializes @c sb using @a str and @c mode|out, and passes @c &sb
	       *  to the base class initializer.
	       *
	       *  That's a lie.  We initialize the base class with NULL, because the
	       *  string class does its own memory management.
	      */
	      explicit
	      basic_ostringstream(const __string_type& __str,
				  ios_base::openmode __mode = ios_base::out)
	      : __ostream_type(), _M_stringbuf(__str, __mode | ios_base::out)
	      { this->init(&_M_stringbuf); }
	
	      /**
	       *  @brief  The destructor does nothing.
	       *
	       *  The buffer is deallocated by the stringbuf object, not the
	       *  formatting stream.
	      */
	      ~basic_ostringstream()
	      { }
	
	      // Members:
	      /**
	       *  @brief  Accessing the underlying buffer.
	       *  @return  The current basic_stringbuf buffer.
	       *
	       *  This hides both signatures of std::basic_ios::rdbuf().
	      */
	      __stringbuf_type*
	      rdbuf() const
	      { return const_cast<__stringbuf_type*>(&_M_stringbuf); }
	
	      /**
	       *  @brief  Copying out the string buffer.
	       *  @return  @c rdbuf()->str()
	      */
	      __string_type
	      str() const
	      { return _M_stringbuf.str(); }
	
	      /**
	       *  @brief  Setting a new buffer.
	       *  @param  __s  The string to use as a new sequence.
	       *
	       *  Calls @c rdbuf()->str(s).
	      */
	      void
	      str(const __string_type& __s)
	      { _M_stringbuf.str(__s); }
	    };
	
	
	  // [27.7.4] Template class basic_stringstream
	  /**
	   *  @brief  Controlling input and output for std::string.
	   *  @ingroup io
	   *
	   *  @tparam _CharT  Type of character stream.
	   *  @tparam _Traits  Traits for character type, defaults to
	   *                   char_traits<_CharT>.
	   *  @tparam _Alloc  Allocator type, defaults to allocator<_CharT>.
	   *
	   *  This class supports reading from and writing to objects of type
	   *  std::basic_string, using the inherited functions from
	   *  std::basic_iostream.  To control the associated sequence, an instance
	   *  of std::basic_stringbuf is used, which this page refers to as @c sb.
	  */
	  template <typename _CharT, typename _Traits, typename _Alloc>
	    class basic_stringstream : public basic_iostream<_CharT, _Traits>
	    {
	    public:
	      // Types:
	      typedef _CharT 					char_type;
	      typedef _Traits 					traits_type;
	      // _GLIBCXX_RESOLVE_LIB_DEFECTS
	      // 251. basic_stringbuf missing allocator_type
	      typedef _Alloc				       	allocator_type;
	      typedef typename traits_type::int_type 		int_type;
	      typedef typename traits_type::pos_type 		pos_type;
	      typedef typename traits_type::off_type 		off_type;
	
	      // Non-standard Types:
	      typedef basic_string<_CharT, _Traits, _Alloc> 	__string_type;
	      typedef basic_stringbuf<_CharT, _Traits, _Alloc> 	__stringbuf_type;
	      typedef basic_iostream<char_type, traits_type>	__iostream_type;
	
	    private:
	      __stringbuf_type	_M_stringbuf;
	
	    public:
	      // Constructors/destructors
	      /**
	       *  @brief  Default constructor starts with an empty string buffer.
	       *  @param  __m  Whether the buffer can read, or write, or both.
	       *
	       *  Initializes @c sb using the mode from @c __m, and passes @c
	       *  &sb to the base class initializer.  Does not allocate any
	       *  buffer.
	       *
	       *  That's a lie.  We initialize the base class with NULL, because the
	       *  string class does its own memory management.
	      */
	      explicit
	      basic_stringstream(ios_base::openmode __m = ios_base::out | ios_base::in)
	      : __iostream_type(), _M_stringbuf(__m)
	      { this->init(&_M_stringbuf); }
	
	      /**
	       *  @brief  Starts with an existing string buffer.
	       *  @param  __str  A string to copy as a starting buffer.
	       *  @param  __m  Whether the buffer can read, or write, or both.
	       *
	       *  Initializes @c sb using @a __str and @c __m, and passes @c &sb
	       *  to the base class initializer.
	       *
	       *  That's a lie.  We initialize the base class with NULL, because the
	       *  string class does its own memory management.
	      */
	      explicit
	      basic_stringstream(const __string_type& __str,
				 ios_base::openmode __m = ios_base::out | ios_base::in)
	      : __iostream_type(), _M_stringbuf(__str, __m)
	      { this->init(&_M_stringbuf); }
	
	      /**
	       *  @brief  The destructor does nothing.
	       *
	       *  The buffer is deallocated by the stringbuf object, not the
	       *  formatting stream.
	      */
	      ~basic_stringstream()
	      { }
	
	      // Members:
	      /**
	       *  @brief  Accessing the underlying buffer.
	       *  @return  The current basic_stringbuf buffer.
	       *
	       *  This hides both signatures of std::basic_ios::rdbuf().
	      */
	      __stringbuf_type*
	      rdbuf() const
	      { return const_cast<__stringbuf_type*>(&_M_stringbuf); }
	
	      /**
	       *  @brief  Copying out the string buffer.
	       *  @return  @c rdbuf()->str()
	      */
	      __string_type
	      str() const
	      { return _M_stringbuf.str(); }
	
	      /**
	       *  @brief  Setting a new buffer.
	       *  @param  __s  The string to use as a new sequence.
	       *
	       *  Calls @c rdbuf()->str(s).
	      */
	      void
	      str(const __string_type& __s)
	      { _M_stringbuf.str(__s); }
	    };
	
	_GLIBCXX_END_NAMESPACE_VERSION
	} // namespace
	
	#include <bits/sstream.tcc>
	
	#endif /* _GLIBCXX_SSTREAM */