// String based streams -*- C++ -*- // Copyright (C) 1997, 1998, 1999, 2002, 2003 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 _CPP_SSTREAM #define _CPP_SSTREAM 1 #pragma GCC system_header #include #include 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 class basic_stringbuf : public basic_streambuf<_CharT, _Traits> { public: // Types: typedef _CharT char_type; typedef _Traits traits_type; #ifdef _GLIBCPP_RESOLVE_LIB_DEFECTS // 251. basic_stringbuf missing allocator_type typedef _Alloc allocator_type; #endif 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 __streambuf_type; typedef basic_string __string_type; typedef typename __string_type::size_type __size_type; //@} protected: // 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_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_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 { if (this->_M_mode & ios_base::out) { // This is the deal: _M_string.size() is a value that // represents the size of the initial string that makes // _M_string, and may not be the correct size of the // current stringbuf internal buffer. __size_type __len = _M_string.size(); if (this->_M_out_cur > this->_M_out_beg) __len = std::max(__size_type(this->_M_out_end - this->_M_out_beg), __len); return __string_type(this->_M_out_beg, this->_M_out_beg + __len); } 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) { // _M_buf_size is a convenient alias for "what the streambuf // thinks the allocated size of the string really is." This is // necessary as ostringstreams are implemented with the // streambufs having control of the allocation and // re-allocation of the internal string object, _M_string. this->_M_buf_size = _M_string.size(); // NB: Start ostringstream buffers at 512 bytes. This is an // experimental value (pronounced "arbitrary" in some of the // hipper english-speaking countries), and can be changed to // suit particular needs. this->_M_buf_size_opt = 512; this->_M_mode = __mode; if (this->_M_mode & (ios_base::ate | ios_base::app)) _M_really_sync(0, this->_M_buf_size); else _M_really_sync(0, 0); } // Overridden virtual functions: // [documentation is inherited] virtual int_type underflow() { if (this->_M_in_cur && this->_M_in_cur < this->_M_in_end) return traits_type::to_int_type(*gptr()); else return traits_type::eof(); } // [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) { _M_string = __string_type(__s, __n); _M_really_sync(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 */ virtual int _M_really_sync(__size_type __i, __size_type __o) { char_type* __base = const_cast(_M_string.data()); bool __testin = this->_M_mode & ios_base::in; bool __testout = this->_M_mode & ios_base::out; __size_type __len = _M_string.size(); this->_M_buf = __base; if (__testin) this->setg(__base, __base + __i, __base + __len); if (__testout) { this->setp(__base, __base + __len); this->_M_out_cur += __o; } return 0; } }; // [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 class basic_istringstream : public basic_istream<_CharT, _Traits> { public: // Types: typedef _CharT char_type; typedef _Traits traits_type; #ifdef _GLIBCPP_RESOLVE_LIB_DEFECTS // 251. basic_stringbuf missing allocator_type typedef _Alloc allocator_type; #endif 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 __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(NULL), _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(NULL), _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 class basic_ostringstream : public basic_ostream<_CharT, _Traits> { public: // Types: typedef _CharT char_type; typedef _Traits traits_type; #ifdef _GLIBCPP_RESOLVE_LIB_DEFECTS // 251. basic_stringbuf missing allocator_type typedef _Alloc allocator_type; #endif 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 __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(NULL), _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(NULL), _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 class basic_stringstream : public basic_iostream<_CharT, _Traits> { public: // Types: typedef _CharT char_type; typedef _Traits traits_type; #ifdef _GLIBCPP_RESOLVE_LIB_DEFECTS // 251. basic_stringbuf missing allocator_type typedef _Alloc allocator_type; #endif 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 __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(NULL), _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(NULL), _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 #ifdef _GLIBCPP_NO_TEMPLATE_EXPORT # define export #endif #ifdef _GLIBCPP_FULLY_COMPLIANT_HEADERS # include #endif #endif