libstdc++-v3/include/bits/sstream.tcc - gcc - Git at Google


            
            // String based streams -*- C++ -*-


            // Copyright (C) 1997-2026 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 bits/sstream.tcc

            
             *  This is an internal header file, included by other library headers.

            
             *  Do not attempt to use it directly. @headername{sstream}

            
             */


            //

            
            // ISO C++ 14882: 27.7  String-based streams

            
            //


            #ifndef _SSTREAM_TCC

            
            #define _SSTREAM_TCC 1


            #ifdef _GLIBCXX_SYSHDR

            
            #pragma GCC system_header

            
            #endif

            
            #pragma GCC diagnostic push

            
            #pragma GCC diagnostic ignored "-Wc++11-extensions" // extern template


            namespace std _GLIBCXX_VISIBILITY(default)

            
            {

            
            _GLIBCXX_BEGIN_NAMESPACE_VERSION


              template <class _CharT, class _Traits, class _Alloc>

            
                typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type

            
                basic_stringbuf<_CharT, _Traits, _Alloc>::

            
                pbackfail(int_type __c)

            
                {

            
                  int_type __ret = traits_type::eof();

            
                  if (this->eback() < this->gptr())

            
            	{

            
            	  // Try to put back __c into input sequence in one of three ways.

            
            	  // Order these tests done in is unspecified by the standard.

            
            	  const bool __testeof = traits_type::eq_int_type(__c, __ret);

            
            	  if (!__testeof)

            
            	    {

            
            	      const bool __testeq = traits_type::eq(traits_type::

            
            						    to_char_type(__c),

            
            						    this->gptr()[-1]);

            
            	      const bool __testout = this->_M_mode & ios_base::out;

            
            	      if (__testeq || __testout)

            
            		{

            
            		  this->gbump(-1);

            
            		  if (!__testeq)

            
            		    *this->gptr() = traits_type::to_char_type(__c);

            
            		  __ret = __c;

            
            		}

            
            	    }

            
            	  else

            
            	    {

            
            	      this->gbump(-1);

            
            	      __ret = traits_type::not_eof(__c);

            
            	    }

            
            	}

            
                  return __ret;

            
                }


              template <class _CharT, class _Traits, class _Alloc>

            
                typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type

            
                basic_stringbuf<_CharT, _Traits, _Alloc>::

            
                overflow(int_type __c)

            
                {

            
                  const bool __testout = this->_M_mode & ios_base::out;

            
                  if (__builtin_expect(!__testout, false))

            
            	return traits_type::eof();


                  const bool __testeof = traits_type::eq_int_type(__c, traits_type::eof());

            
                  if (__builtin_expect(__testeof, false))

            
            	return traits_type::not_eof(__c);


                  const __size_type __capacity = _M_string.capacity();


            #if _GLIBCXX_USE_CXX11_ABI

            
                  if (size_t(this->epptr() - this->pbase()) < __capacity)

            
            	{

            
            	  // There is additional capacity in _M_string that can be used.

            
            	  char_type* __base = const_cast<char_type*>(_M_string.data());

            
            	  _M_pbump(__base, __base + __capacity, this->pptr() - this->pbase());

            
            	  if (_M_mode & ios_base::in)

            
            	    {

            
            	      const __size_type __nget = this->gptr() - this->eback();

            
            	      const __size_type __eget = this->egptr() - this->eback();

            
            	      this->setg(__base, __base + __nget, __base + __eget + 1);

            
            	    }

            
            	  *this->pptr() = traits_type::to_char_type(__c);

            
            	  this->pbump(1);

            
            	  return __c;

            
            	}

            
            #endif


                  const __size_type __max_size = _M_string.max_size();

            
                  const bool __testput = this->pptr() < this->epptr();

            
                  if (__builtin_expect(!__testput && __capacity == __max_size, false))

            
            	return traits_type::eof();


                  // Try to append __c into output sequence in one of two ways.

            
                  // Order these tests done in is unspecified by the standard.

            
                  const char_type __conv = traits_type::to_char_type(__c);

            
                  if (!__testput)

            
            	{

            
            	  // NB: Start ostringstream buffers at 512 chars.  This is an

            
            	  // experimental value (pronounced "arbitrary" in some of the

            
            	  // hipper English-speaking countries), and can be changed to

            
            	  // suit particular needs.

            
            	  //

            
            	  // _GLIBCXX_RESOLVE_LIB_DEFECTS

            
            	  // 169. Bad efficiency of overflow() mandated

            
            	  // 432. stringbuf::overflow() makes only one write position

            
            	  //      available

            
            	  const __size_type __opt_len = std::max(__size_type(2 * __capacity),

            
            						 __size_type(512));

            
            	  const __size_type __len = std::min(__opt_len, __max_size);

            
            	  __string_type __tmp(_M_string.get_allocator());

            
            	  __tmp.reserve(__len);

            
            	  if (this->pbase())

            
            	    __tmp.assign(this->pbase(), this->epptr() - this->pbase());

            
            	  __tmp.push_back(__conv);

            
            	  _M_string.swap(__tmp);

            
            	  _M_sync(const_cast<char_type*>(_M_string.data()),

            
            		  this->gptr() - this->eback(), this->pptr() - this->pbase());

            
            	}

            
                  else

            
            	*this->pptr() = __conv;

            
                  this->pbump(1);

            
                  return __c;

            
                }


              template <class _CharT, class _Traits, class _Alloc>

            
                typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type

            
                basic_stringbuf<_CharT, _Traits, _Alloc>::

            
                underflow()

            
                {

            
                  int_type __ret = traits_type::eof();

            
                  const bool __testin = this->_M_mode & ios_base::in;

            
                  if (__testin)

            
            	{

            
            	  // Update egptr() to match the actual string end.

            
            	  _M_update_egptr();


            	  if (this->gptr() < this->egptr())

            
            	    __ret = traits_type::to_int_type(*this->gptr());

            
            	}

            
                  return __ret;

            
                }


              template <class _CharT, class _Traits, class _Alloc>

            
                typename basic_stringbuf<_CharT, _Traits, _Alloc>::pos_type

            
                basic_stringbuf<_CharT, _Traits, _Alloc>::

            
                seekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode __mode)

            
                {

            
                  pos_type __ret =  pos_type(off_type(-1));

            
                  bool __testin = (ios_base::in & this->_M_mode & __mode) != 0;

            
                  bool __testout = (ios_base::out & this->_M_mode & __mode) != 0;

            
                  const bool __testboth = __testin && __testout && __way != ios_base::cur;

            
                  __testin &= !(__mode & ios_base::out);

            
                  __testout &= !(__mode & ios_base::in);


                  // _GLIBCXX_RESOLVE_LIB_DEFECTS

            
                  // 453. basic_stringbuf::seekoff need not always fail for an empty stream.

            
                  const char_type* __beg = __testin ? this->eback() : this->pbase();

            
                  if ((__beg || !__off) && (__testin || __testout || __testboth))

            
            	{

            
            	  _M_update_egptr();


            	  off_type __newoffi = __off;

            
            	  off_type __newoffo = __newoffi;

            
            	  if (__way == ios_base::cur)

            
            	    {

            
            	      __newoffi += this->gptr() - __beg;

            
            	      __newoffo += this->pptr() - __beg;

            
            	    }

            
            	  else if (__way == ios_base::end)

            
            	    __newoffo = __newoffi += this->egptr() - __beg;


            	  if ((__testin || __testboth)

            
            	      && __newoffi >= 0

            
            	      && this->egptr() - __beg >= __newoffi)

            
            	    {

            
            	      this->setg(this->eback(), this->eback() + __newoffi,

            
            			 this->egptr());

            
            	      __ret = pos_type(__newoffi);

            
            	    }

            
            	  if ((__testout || __testboth)

            
            	      && __newoffo >= 0

            
            	      && this->egptr() - __beg >= __newoffo)

            
            	    {

            
            	      _M_pbump(this->pbase(), this->epptr(), __newoffo);

            
            	      __ret = pos_type(__newoffo);

            
            	    }

            
            	}

            
                  return __ret;

            
                }


              template <class _CharT, class _Traits, class _Alloc>

            
                typename basic_stringbuf<_CharT, _Traits, _Alloc>::pos_type

            
                basic_stringbuf<_CharT, _Traits, _Alloc>::

            
                seekpos(pos_type __sp, ios_base::openmode __mode)

            
                {

            
                  pos_type __ret =  pos_type(off_type(-1));

            
                  const bool __testin = (ios_base::in & this->_M_mode & __mode) != 0;

            
                  const bool __testout = (ios_base::out & this->_M_mode & __mode) != 0;


                  const char_type* __beg = __testin ? this->eback() : this->pbase();

            
                  if ((__beg || !off_type(__sp)) && (__testin || __testout))

            
            	{

            
            	  _M_update_egptr();


            	  const off_type __pos(__sp);

            
            	  const bool __testpos = (0 <= __pos

            
            				  && __pos <= this->egptr() - __beg);

            
            	  if (__testpos)

            
            	    {

            
            	      if (__testin)

            
            		this->setg(this->eback(), this->eback() + __pos,

            
            			   this->egptr());

            
            	      if (__testout)

            
            		_M_pbump(this->pbase(), this->epptr(), __pos);

            
            	      __ret = __sp;

            
            	    }

            
            	}

            
                  return __ret;

            
                }


              template <class _CharT, class _Traits, class _Alloc>

            
                void

            
                basic_stringbuf<_CharT, _Traits, _Alloc>::

            
                _M_sync(char_type* __base, __size_type __i, __size_type __o)

            
                {

            
                  const bool __testin = _M_mode & ios_base::in;

            
                  const bool __testout = _M_mode & ios_base::out;

            
                  char_type* __endg = __base + _M_string.size();

            
                  char_type* __endp = __base + _M_string.capacity();


                  if (__base != _M_string.data())

            
            	{

            
            	  // setbuf: __i == size of buffer area (_M_string.size() == 0).

            
            	  __endg += __i;

            
            	  __i = 0;

            
            	  __endp = __endg;

            
            	}


                  if (__testin)

            
            	this->setg(__base, __base + __i, __endg);

            
                  if (__testout)

            
            	{

            
            	  _M_pbump(__base, __endp, __o);

            
            	  // egptr() always tracks the string end.  When !__testin,

            
            	  // for the correct functioning of the streambuf inlines

            
            	  // the other get area pointers are identical.

            
            	  if (!__testin)

            
            	    this->setg(__endg, __endg, __endg);

            
            	}

            
                }


              template <class _CharT, class _Traits, class _Alloc>

            
                void

            
                basic_stringbuf<_CharT, _Traits, _Alloc>::

            
                _M_pbump(char_type* __pbeg, char_type* __pend, off_type __off)

            
                {

            
                  this->setp(__pbeg, __pend);

            
                  while (__off > __gnu_cxx::__numeric_traits<int>::__max)

            
            	{

            
            	  this->pbump(__gnu_cxx::__numeric_traits<int>::__max);

            
            	  __off -= __gnu_cxx::__numeric_traits<int>::__max;

            
            	}

            
                  this->pbump(__off);

            
                }


              // Inhibit implicit instantiations for required instantiations,

            
              // which are defined via explicit instantiations elsewhere.

            
            #if _GLIBCXX_EXTERN_TEMPLATE

            
              extern template class basic_stringbuf<char>;

            
              extern template class basic_istringstream<char>;

            
              extern template class basic_ostringstream<char>;

            
              extern template class basic_stringstream<char>;


            #ifdef _GLIBCXX_USE_WCHAR_T

            
              extern template class basic_stringbuf<wchar_t>;

            
              extern template class basic_istringstream<wchar_t>;

            
              extern template class basic_ostringstream<wchar_t>;

            
              extern template class basic_stringstream<wchar_t>;

            
            #endif

            
            #endif


            _GLIBCXX_END_NAMESPACE_VERSION

            
            } // namespace std


            #pragma GCC diagnostic pop

            
            #endif
	// String based streams -- C++ --

	// Copyright (C) 1997-2026 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 bits/sstream.tcc
	* This is an internal header file, included by other library headers.
	* Do not attempt to use it directly. @headername{sstream}
	*/

	//
	// ISO C++ 14882: 27.7 String-based streams
	//

	#ifndef _SSTREAM_TCC
	#define _SSTREAM_TCC 1

	#ifdef _GLIBCXX_SYSHDR
	#pragma GCC system_header
	#endif
	#pragma GCC diagnostic push
	#pragma GCC diagnostic ignored "-Wc++11-extensions" // extern template

	namespace std _GLIBCXX_VISIBILITY(default)
	{
	_GLIBCXX_BEGIN_NAMESPACE_VERSION

	template <class _CharT, class _Traits, class _Alloc>
	typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type
	basic_stringbuf<_CharT, _Traits, _Alloc>::
	pbackfail(int_type __c)
	{
	int_type __ret = traits_type::eof();
	if (this->eback() < this->gptr())
	{
	// Try to put back __c into input sequence in one of three ways.
	// Order these tests done in is unspecified by the standard.
	const bool __testeof = traits_type::eq_int_type(__c, __ret);
	if (!__testeof)
	{
	const bool __testeq = traits_type::eq(traits_type::
	to_char_type(__c),
	this->gptr()[-1]);
	const bool __testout = this->_M_mode & ios_base::out;
	if (__testeq \|\| __testout)
	{
	this->gbump(-1);
	if (!__testeq)
	*this->gptr() = traits_type::to_char_type(__c);
	__ret = __c;
	}
	}
	else
	{
	this->gbump(-1);
	__ret = traits_type::not_eof(__c);
	}
	}
	return __ret;
	}

	template <class _CharT, class _Traits, class _Alloc>
	typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type
	basic_stringbuf<_CharT, _Traits, _Alloc>::
	overflow(int_type __c)
	{
	const bool __testout = this->_M_mode & ios_base::out;
	if (__builtin_expect(!__testout, false))
	return traits_type::eof();

	const bool __testeof = traits_type::eq_int_type(__c, traits_type::eof());
	if (__builtin_expect(__testeof, false))
	return traits_type::not_eof(__c);

	const __size_type __capacity = _M_string.capacity();

	#if _GLIBCXX_USE_CXX11_ABI
	if (size_t(this->epptr() - this->pbase()) < __capacity)
	{
	// There is additional capacity in _M_string that can be used.
	char_type* __base = const_cast<char_type*>(_M_string.data());
	_M_pbump(__base, __base + __capacity, this->pptr() - this->pbase());
	if (_M_mode & ios_base::in)
	{
	const __size_type __nget = this->gptr() - this->eback();
	const __size_type __eget = this->egptr() - this->eback();
	this->setg(__base, __base + __nget, __base + __eget + 1);
	}
	*this->pptr() = traits_type::to_char_type(__c);
	this->pbump(1);
	return __c;
	}
	#endif

	const __size_type __max_size = _M_string.max_size();
	const bool __testput = this->pptr() < this->epptr();
	if (__builtin_expect(!__testput && __capacity == __max_size, false))
	return traits_type::eof();

	// Try to append __c into output sequence in one of two ways.
	// Order these tests done in is unspecified by the standard.
	const char_type __conv = traits_type::to_char_type(__c);
	if (!__testput)
	{
	// NB: Start ostringstream buffers at 512 chars. This is an
	// experimental value (pronounced "arbitrary" in some of the
	// hipper English-speaking countries), and can be changed to
	// suit particular needs.
	//
	// _GLIBCXX_RESOLVE_LIB_DEFECTS
	// 169. Bad efficiency of overflow() mandated
	// 432. stringbuf::overflow() makes only one write position
	// available
	const __size_type __opt_len = std::max(__size_type(2 * __capacity),
	__size_type(512));
	const __size_type __len = std::min(__opt_len, __max_size);
	__string_type __tmp(_M_string.get_allocator());
	__tmp.reserve(__len);
	if (this->pbase())
	__tmp.assign(this->pbase(), this->epptr() - this->pbase());
	__tmp.push_back(__conv);
	_M_string.swap(__tmp);
	_M_sync(const_cast<char_type*>(_M_string.data()),
	this->gptr() - this->eback(), this->pptr() - this->pbase());
	}
	else
	*this->pptr() = __conv;
	this->pbump(1);
	return __c;
	}

	template <class _CharT, class _Traits, class _Alloc>
	typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type
	basic_stringbuf<_CharT, _Traits, _Alloc>::
	underflow()
	{
	int_type __ret = traits_type::eof();
	const bool __testin = this->_M_mode & ios_base::in;
	if (__testin)
	{
	// Update egptr() to match the actual string end.
	_M_update_egptr();

	if (this->gptr() < this->egptr())
	__ret = traits_type::to_int_type(*this->gptr());
	}
	return __ret;
	}

	template <class _CharT, class _Traits, class _Alloc>
	typename basic_stringbuf<_CharT, _Traits, _Alloc>::pos_type
	basic_stringbuf<_CharT, _Traits, _Alloc>::
	seekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode __mode)
	{
	pos_type __ret = pos_type(off_type(-1));
	bool __testin = (ios_base::in & this->_M_mode & __mode) != 0;
	bool __testout = (ios_base::out & this->_M_mode & __mode) != 0;
	const bool __testboth = __testin && __testout && __way != ios_base::cur;
	__testin &= !(__mode & ios_base::out);
	__testout &= !(__mode & ios_base::in);

	// _GLIBCXX_RESOLVE_LIB_DEFECTS
	// 453. basic_stringbuf::seekoff need not always fail for an empty stream.
	const char_type* __beg = __testin ? this->eback() : this->pbase();
	if ((__beg \|\| !__off) && (__testin \|\| __testout \|\| __testboth))
	{
	_M_update_egptr();

	off_type __newoffi = __off;
	off_type __newoffo = __newoffi;
	if (__way == ios_base::cur)
	{
	__newoffi += this->gptr() - __beg;
	__newoffo += this->pptr() - __beg;
	}
	else if (__way == ios_base::end)
	__newoffo = __newoffi += this->egptr() - __beg;

	if ((__testin \|\| __testboth)
	&& __newoffi >= 0
	&& this->egptr() - __beg >= __newoffi)
	{
	this->setg(this->eback(), this->eback() + __newoffi,
	this->egptr());
	__ret = pos_type(__newoffi);
	}
	if ((__testout \|\| __testboth)
	&& __newoffo >= 0
	&& this->egptr() - __beg >= __newoffo)
	{
	_M_pbump(this->pbase(), this->epptr(), __newoffo);
	__ret = pos_type(__newoffo);
	}
	}
	return __ret;
	}

	template <class _CharT, class _Traits, class _Alloc>
	typename basic_stringbuf<_CharT, _Traits, _Alloc>::pos_type
	basic_stringbuf<_CharT, _Traits, _Alloc>::
	seekpos(pos_type __sp, ios_base::openmode __mode)
	{
	pos_type __ret = pos_type(off_type(-1));
	const bool __testin = (ios_base::in & this->_M_mode & __mode) != 0;
	const bool __testout = (ios_base::out & this->_M_mode & __mode) != 0;

	const char_type* __beg = __testin ? this->eback() : this->pbase();
	if ((__beg \|\| !off_type(__sp)) && (__testin \|\| __testout))
	{
	_M_update_egptr();

	const off_type __pos(__sp);
	const bool __testpos = (0 <= __pos
	&& __pos <= this->egptr() - __beg);
	if (__testpos)
	{
	if (__testin)
	this->setg(this->eback(), this->eback() + __pos,
	this->egptr());
	if (__testout)
	_M_pbump(this->pbase(), this->epptr(), __pos);
	__ret = __sp;
	}
	}
	return __ret;
	}

	template <class _CharT, class _Traits, class _Alloc>
	void
	basic_stringbuf<_CharT, _Traits, _Alloc>::
	_M_sync(char_type* __base, __size_type __i, __size_type __o)
	{
	const bool __testin = _M_mode & ios_base::in;
	const bool __testout = _M_mode & ios_base::out;
	char_type* __endg = __base + _M_string.size();
	char_type* __endp = __base + _M_string.capacity();

	if (__base != _M_string.data())
	{
	// setbuf: __i == size of buffer area (_M_string.size() == 0).
	__endg += __i;
	__i = 0;
	__endp = __endg;
	}

	if (__testin)
	this->setg(__base, __base + __i, __endg);
	if (__testout)
	{
	_M_pbump(__base, __endp, __o);
	// egptr() always tracks the string end. When !__testin,
	// for the correct functioning of the streambuf inlines
	// the other get area pointers are identical.
	if (!__testin)
	this->setg(__endg, __endg, __endg);
	}
	}

	template <class _CharT, class _Traits, class _Alloc>
	void
	basic_stringbuf<_CharT, _Traits, _Alloc>::
	_M_pbump(char_type* __pbeg, char_type* __pend, off_type __off)
	{
	this->setp(__pbeg, __pend);
	while (__off > __gnu_cxx::__numeric_traits<int>::__max)
	{
	this->pbump(__gnu_cxx::__numeric_traits<int>::__max);
	__off -= __gnu_cxx::__numeric_traits<int>::__max;
	}
	this->pbump(__off);
	}

	// Inhibit implicit instantiations for required instantiations,
	// which are defined via explicit instantiations elsewhere.
	#if _GLIBCXX_EXTERN_TEMPLATE
	extern template class basic_stringbuf<char>;
	extern template class basic_istringstream<char>;
	extern template class basic_ostringstream<char>;
	extern template class basic_stringstream<char>;

	#ifdef _GLIBCXX_USE_WCHAR_T
	extern template class basic_stringbuf<wchar_t>;
	extern template class basic_istringstream<wchar_t>;
	extern template class basic_ostringstream<wchar_t>;
	extern template class basic_stringstream<wchar_t>;
	#endif
	#endif

	_GLIBCXX_END_NAMESPACE_VERSION
	} // namespace std

	#pragma GCC diagnostic pop
	#endif