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- // String based streams -*- C++ -*-
-
- // Copyright (C) 1997, 1998, 1999, 2002, 2003, 2004
- // 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 2, 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.
-
- // You should have received a copy of the GNU General Public License along
- // with this library; see the file COPYING. If not, write to the Free
- // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
- // USA.
-
- // As a special exception, you may use this file as part of a free software
- // library without restriction. Specifically, if other files instantiate
- // templates or use macros or inline functions from this file, or you compile
- // this file and link it with other files to produce an executable, this
- // file does not by itself cause the resulting executable to be covered by
- // the GNU General Public License. This exception does not however
- // invalidate any other reasons why the executable file might be covered by
- // the GNU General Public License.
-
- //
- // ISO C++ 14882: 27.7 String-based streams
- //
-
- /** @file sstream
- * This is a Standard C++ Library header. You should @c #include this header
- * in your programs, rather than any of the "st[dl]_*.h" implementation files.
- */
-
- #ifndef _GLIBCXX_SSTREAM
- #define _GLIBCXX_SSTREAM 1
-
- #pragma GCC system_header
-
- #include <istream>
- #include <ostream>
-
- namespace std
- {
- // [27.7.1] template class basic_stringbuf
- /**
- * @brief The actual work of input and output (for std::string).
- *
- * 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;
-
- //@{
- /**
- * @if maint
- * @doctodo
- * @endif
- */
- 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:
- /**
- * @if maint
- * Place to stash in || out || in | out settings for current stringbuf.
- * @endif
- */
- ios_base::openmode _M_mode;
-
- // Data Members:
- /**
- * @if maint
- * @doctodo
- * @endif
- */
- __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(), _M_string()
- { _M_stringbuf_init(__mode); }
-
- /**
- * @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.
- *
- * "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." [27.7.1.2]/1
- */
- __string_type
- str() const
- {
- const bool __testout = this->_M_mode & ios_base::out;
- if (__testout)
- {
- // The current egptr() may not be the actual string end.
- if (this->pptr() > this->egptr())
- return __string_type(this->pbase(), this->pptr());
- else
- return __string_type(this->pbase(), this->egptr());
- }
- else
- return _M_string;
- }
-
- /**
- * @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(this->_M_mode);
- }
-
- protected:
- // Common initialization code for both ctors goes here.
- /**
- * @if maint
- * @doctodo
- * @endif
- */
- void
- _M_stringbuf_init(ios_base::openmode __mode)
- {
- this->_M_mode = __mode;
-
- __size_type __len = 0;
- if (this->_M_mode & (ios_base::ate | ios_base::app))
- __len = _M_string.size();
- _M_sync(const_cast<char_type*>(_M_string.data()), 0, __len);
- }
-
- // [documentation is inherited]
- virtual int_type
- underflow();
-
- // [documentation is inherited]
- virtual int_type
- pbackfail(int_type __c = traits_type::eof());
-
- // [documentation is inherited]
- 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++/27_io/howto.html#2
- * 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 = __string_type(__s, __n);
-
- // Step 2: Use the external array.
- _M_sync(__s, 0, 0);
- }
- return this;
- }
-
- // [documentation is inherited]
- virtual pos_type
- seekoff(off_type __off, ios_base::seekdir __way,
- ios_base::openmode __mode = ios_base::in | ios_base::out);
-
- // [documentation is inherited]
- 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.
- // Assumes: contents of _M_string and internal buffer match exactly.
- // __i == _M_in_cur - _M_in_beg
- // __o == _M_out_cur - _M_out_beg
- /**
- * @if maint
- * @doctodo
- * @endif
- */
- void
- _M_sync(char_type* __base, __size_type __i, __size_type __o)
- {
- const bool __testin = this->_M_mode & ios_base::in;
- const bool __testout = this->_M_mode & ios_base::out;
- const __size_type __len = _M_string.size();
-
- if (__testin)
- this->setg(__base, __base + __i, __base + __len);
- if (__testout)
- {
- this->setp(__base, __base + _M_string.capacity());
- this->pbump(__o);
- // We need a pointer to the string end anyway, even when
- // !__testin: in that case, however, for the correct
- // functioning of the streambuf inlines all the get area
- // pointers must be identical.
- if (!__testin)
- this->setg(__base + __len, __base + __len, __base + __len);
- }
- }
-
- // Internal function for correctly updating egptr() to the actual
- // string end.
- void
- _M_update_egptr()
- {
- const bool __testin = this->_M_mode & ios_base::in;
- const bool __testout = this->_M_mode & ios_base::out;
-
- if (__testout && this->pptr() > this->egptr())
- if (__testin)
- this->setg(this->eback(), this->gptr(), this->pptr());
- else
- this->setg(this->pptr(), this->pptr(), this->pptr());
- }
- };
-
-
- // [27.7.2] Template class basic_istringstream
- /**
- * @brief Controlling input for std::string.
- *
- * 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:
- /**
- * @if maint
- * @doctodo
- * @endif
- */
- __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.
- *
- * @if maint
- * That's a lie. We initialize the base class with NULL, because the
- * string class does its own memory management.
- * @endif
- */
- 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.
- *
- * @if maint
- * That's a lie. We initialize the base class with NULL, because the
- * string class does its own memory management.
- * @endif
- */
- 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.
- *
- * 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:
- /**
- * @if maint
- * @doctodo
- * @endif
- */
- __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.
- *
- * @if maint
- * That's a lie. We initialize the base class with NULL, because the
- * string class does its own memory management.
- * @endif
- */
- 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.
- *
- * @if maint
- * That's a lie. We initialize the base class with NULL, because the
- * string class does its own memory management.
- * @endif
- */
- 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.
- *
- * 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:
- /**
- * @if maint
- * @doctodo
- * @endif
- */
- __stringbuf_type _M_stringbuf;
-
- public:
- // Constructors/destructors
- /**
- * @brief Default constructor starts with an empty string buffer.
- * @param mode Whether the buffer can read, or write, or both.
- *
- * Initializes @c sb using @c mode, and passes @c &sb to the base
- * class initializer. Does not allocate any buffer.
- *
- * @if maint
- * That's a lie. We initialize the base class with NULL, because the
- * string class does its own memory management.
- * @endif
- */
- 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 mode Whether the buffer can read, or write, or both.
- *
- * Initializes @c sb using @a str and @c mode, and passes @c &sb
- * to the base class initializer.
- *
- * @if maint
- * That's a lie. We initialize the base class with NULL, because the
- * string class does its own memory management.
- * @endif
- */
- 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); }
- };
- } // namespace std
-
- #ifndef _GLIBCXX_EXPORT_TEMPLATE
- # include <bits/sstream.tcc>
- #endif
-
- #endif /* _GLIBCXX_SSTREAM */
-