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- // String based streams -*- C++ -*-
-
- // Copyright (C) 1997-2020 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
-
- #pragma GCC system_header
-
- 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 ((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
-
- #endif
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