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Diffstat (limited to 'gcc-4.4.3/libstdc++-v3/include/bits/basic_ios.h')
| -rw-r--r-- | gcc-4.4.3/libstdc++-v3/include/bits/basic_ios.h | 474 |
1 files changed, 474 insertions, 0 deletions
diff --git a/gcc-4.4.3/libstdc++-v3/include/bits/basic_ios.h b/gcc-4.4.3/libstdc++-v3/include/bits/basic_ios.h new file mode 100644 index 000000000..ee1b64650 --- /dev/null +++ b/gcc-4.4.3/libstdc++-v3/include/bits/basic_ios.h @@ -0,0 +1,474 @@ +// Iostreams base classes -*- C++ -*- + +// Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, +// 2006, 2007, 2008, 2009 +// 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 basic_ios.h + * This is an internal header file, included by other library headers. + * You should not attempt to use it directly. + */ + +#ifndef _BASIC_IOS_H +#define _BASIC_IOS_H 1 + +#pragma GCC system_header + +#include <bits/localefwd.h> +#include <bits/locale_classes.h> +#include <bits/locale_facets.h> +#include <bits/streambuf_iterator.h> + +_GLIBCXX_BEGIN_NAMESPACE(std) + + template<typename _Facet> + inline const _Facet& + __check_facet(const _Facet* __f) + { + if (!__f) + __throw_bad_cast(); + return *__f; + } + + // 27.4.5 Template class basic_ios + /** + * @brief Virtual base class for all stream classes. + * @ingroup io + * + * Most of the member functions called dispatched on stream objects + * (e.g., @c std::cout.foo(bar);) are consolidated in this class. + */ + template<typename _CharT, typename _Traits> + class basic_ios : public ios_base + { + public: + //@{ + /** + * These are standard types. They permit a standardized way of + * referring to names of (or names dependant on) the template + * parameters, which are specific to the implementation. + */ + typedef _CharT char_type; + typedef typename _Traits::int_type int_type; + typedef typename _Traits::pos_type pos_type; + typedef typename _Traits::off_type off_type; + typedef _Traits traits_type; + //@} + + //@{ + /** + * These are non-standard types. + */ + typedef ctype<_CharT> __ctype_type; + typedef num_put<_CharT, ostreambuf_iterator<_CharT, _Traits> > + __num_put_type; + typedef num_get<_CharT, istreambuf_iterator<_CharT, _Traits> > + __num_get_type; + //@} + + // Data members: + protected: + basic_ostream<_CharT, _Traits>* _M_tie; + mutable char_type _M_fill; + mutable bool _M_fill_init; + basic_streambuf<_CharT, _Traits>* _M_streambuf; + + // Cached use_facet<ctype>, which is based on the current locale info. + const __ctype_type* _M_ctype; + // For ostream. + const __num_put_type* _M_num_put; + // For istream. + const __num_get_type* _M_num_get; + + public: + //@{ + /** + * @brief The quick-and-easy status check. + * + * This allows you to write constructs such as + * "if (!a_stream) ..." and "while (a_stream) ..." + */ + operator void*() const + { return this->fail() ? 0 : const_cast<basic_ios*>(this); } + + bool + operator!() const + { return this->fail(); } + //@} + + /** + * @brief Returns the error state of the stream buffer. + * @return A bit pattern (well, isn't everything?) + * + * See std::ios_base::iostate for the possible bit values. Most + * users will call one of the interpreting wrappers, e.g., good(). + */ + iostate + rdstate() const + { return _M_streambuf_state; } + + /** + * @brief [Re]sets the error state. + * @param state The new state flag(s) to set. + * + * See std::ios_base::iostate for the possible bit values. Most + * users will not need to pass an argument. + */ + void + clear(iostate __state = goodbit); + + /** + * @brief Sets additional flags in the error state. + * @param state The additional state flag(s) to set. + * + * See std::ios_base::iostate for the possible bit values. + */ + void + setstate(iostate __state) + { this->clear(this->rdstate() | __state); } + + // Flip the internal state on for the proper state bits, then re + // throws the propagated exception if bit also set in + // exceptions(). + void + _M_setstate(iostate __state) + { + // 27.6.1.2.1 Common requirements. + // Turn this on without causing an ios::failure to be thrown. + _M_streambuf_state |= __state; + if (this->exceptions() & __state) + __throw_exception_again; + } + + /** + * @brief Fast error checking. + * @return True if no error flags are set. + * + * A wrapper around rdstate. + */ + bool + good() const + { return this->rdstate() == 0; } + + /** + * @brief Fast error checking. + * @return True if the eofbit is set. + * + * Note that other iostate flags may also be set. + */ + bool + eof() const + { return (this->rdstate() & eofbit) != 0; } + + /** + * @brief Fast error checking. + * @return True if either the badbit or the failbit is set. + * + * Checking the badbit in fail() is historical practice. + * Note that other iostate flags may also be set. + */ + bool + fail() const + { return (this->rdstate() & (badbit | failbit)) != 0; } + + /** + * @brief Fast error checking. + * @return True if the badbit is set. + * + * Note that other iostate flags may also be set. + */ + bool + bad() const + { return (this->rdstate() & badbit) != 0; } + + /** + * @brief Throwing exceptions on errors. + * @return The current exceptions mask. + * + * This changes nothing in the stream. See the one-argument version + * of exceptions(iostate) for the meaning of the return value. + */ + iostate + exceptions() const + { return _M_exception; } + + /** + * @brief Throwing exceptions on errors. + * @param except The new exceptions mask. + * + * By default, error flags are set silently. You can set an + * exceptions mask for each stream; if a bit in the mask becomes set + * in the error flags, then an exception of type + * std::ios_base::failure is thrown. + * + * If the error flag is already set when the exceptions mask is + * added, the exception is immediately thrown. Try running the + * following under GCC 3.1 or later: + * @code + * #include <iostream> + * #include <fstream> + * #include <exception> + * + * int main() + * { + * std::set_terminate (__gnu_cxx::__verbose_terminate_handler); + * + * std::ifstream f ("/etc/motd"); + * + * std::cerr << "Setting badbit\n"; + * f.setstate (std::ios_base::badbit); + * + * std::cerr << "Setting exception mask\n"; + * f.exceptions (std::ios_base::badbit); + * } + * @endcode + */ + void + exceptions(iostate __except) + { + _M_exception = __except; + this->clear(_M_streambuf_state); + } + + // Constructor/destructor: + /** + * @brief Constructor performs initialization. + * + * The parameter is passed by derived streams. + */ + explicit + basic_ios(basic_streambuf<_CharT, _Traits>* __sb) + : ios_base(), _M_tie(0), _M_fill(), _M_fill_init(false), _M_streambuf(0), + _M_ctype(0), _M_num_put(0), _M_num_get(0) + { this->init(__sb); } + + /** + * @brief Empty. + * + * The destructor does nothing. More specifically, it does not + * destroy the streambuf held by rdbuf(). + */ + virtual + ~basic_ios() { } + + // Members: + /** + * @brief Fetches the current @e tied stream. + * @return A pointer to the tied stream, or NULL if the stream is + * not tied. + * + * A stream may be @e tied (or synchronized) to a second output + * stream. When this stream performs any I/O, the tied stream is + * first flushed. For example, @c std::cin is tied to @c std::cout. + */ + basic_ostream<_CharT, _Traits>* + tie() const + { return _M_tie; } + + /** + * @brief Ties this stream to an output stream. + * @param tiestr The output stream. + * @return The previously tied output stream, or NULL if the stream + * was not tied. + * + * This sets up a new tie; see tie() for more. + */ + basic_ostream<_CharT, _Traits>* + tie(basic_ostream<_CharT, _Traits>* __tiestr) + { + basic_ostream<_CharT, _Traits>* __old = _M_tie; + _M_tie = __tiestr; + return __old; + } + + /** + * @brief Accessing the underlying buffer. + * @return The current stream buffer. + * + * This does not change the state of the stream. + */ + basic_streambuf<_CharT, _Traits>* + rdbuf() const + { return _M_streambuf; } + + /** + * @brief Changing the underlying buffer. + * @param sb The new stream buffer. + * @return The previous stream buffer. + * + * Associates a new buffer with the current stream, and clears the + * error state. + * + * Due to historical accidents which the LWG refuses to correct, the + * I/O library suffers from a design error: this function is hidden + * in derived classes by overrides of the zero-argument @c rdbuf(), + * which is non-virtual for hysterical raisins. As a result, you + * must use explicit qualifications to access this function via any + * derived class. For example: + * + * @code + * std::fstream foo; // or some other derived type + * std::streambuf* p = .....; + * + * foo.ios::rdbuf(p); // ios == basic_ios<char> + * @endcode + */ + basic_streambuf<_CharT, _Traits>* + rdbuf(basic_streambuf<_CharT, _Traits>* __sb); + + /** + * @brief Copies fields of __rhs into this. + * @param __rhs The source values for the copies. + * @return Reference to this object. + * + * All fields of __rhs are copied into this object except that rdbuf() + * and rdstate() remain unchanged. All values in the pword and iword + * arrays are copied. Before copying, each callback is invoked with + * erase_event. After copying, each (new) callback is invoked with + * copyfmt_event. The final step is to copy exceptions(). + */ + basic_ios& + copyfmt(const basic_ios& __rhs); + + /** + * @brief Retrieves the "empty" character. + * @return The current fill character. + * + * It defaults to a space (' ') in the current locale. + */ + char_type + fill() const + { + if (!_M_fill_init) + { + _M_fill = this->widen(' '); + _M_fill_init = true; + } + return _M_fill; + } + + /** + * @brief Sets a new "empty" character. + * @param ch The new character. + * @return The previous fill character. + * + * The fill character is used to fill out space when P+ characters + * have been requested (e.g., via setw), Q characters are actually + * used, and Q<P. It defaults to a space (' ') in the current locale. + */ + char_type + fill(char_type __ch) + { + char_type __old = this->fill(); + _M_fill = __ch; + return __old; + } + + // Locales: + /** + * @brief Moves to a new locale. + * @param loc The new locale. + * @return The previous locale. + * + * Calls @c ios_base::imbue(loc), and if a stream buffer is associated + * with this stream, calls that buffer's @c pubimbue(loc). + * + * Additional l10n notes are at + * http://gcc.gnu.org/onlinedocs/libstdc++/manual/localization.html + */ + locale + imbue(const locale& __loc); + + /** + * @brief Squeezes characters. + * @param c The character to narrow. + * @param dfault The character to narrow. + * @return The narrowed character. + * + * Maps a character of @c char_type to a character of @c char, + * if possible. + * + * Returns the result of + * @code + * std::use_facet<ctype<char_type> >(getloc()).narrow(c,dfault) + * @endcode + * + * Additional l10n notes are at + * http://gcc.gnu.org/onlinedocs/libstdc++/manual/localization.html + */ + char + narrow(char_type __c, char __dfault) const + { return __check_facet(_M_ctype).narrow(__c, __dfault); } + + /** + * @brief Widens characters. + * @param c The character to widen. + * @return The widened character. + * + * Maps a character of @c char to a character of @c char_type. + * + * Returns the result of + * @code + * std::use_facet<ctype<char_type> >(getloc()).widen(c) + * @endcode + * + * Additional l10n notes are at + * http://gcc.gnu.org/onlinedocs/libstdc++/manual/localization.html + */ + char_type + widen(char __c) const + { return __check_facet(_M_ctype).widen(__c); } + + protected: + // 27.4.5.1 basic_ios constructors + /** + * @brief Empty. + * + * The default constructor does nothing and is not normally + * accessible to users. + */ + basic_ios() + : ios_base(), _M_tie(0), _M_fill(char_type()), _M_fill_init(false), + _M_streambuf(0), _M_ctype(0), _M_num_put(0), _M_num_get(0) + { } + + /** + * @brief All setup is performed here. + * + * This is called from the public constructor. It is not virtual and + * cannot be redefined. + */ + void + init(basic_streambuf<_CharT, _Traits>* __sb); + + void + _M_cache_locale(const locale& __loc); + }; + +_GLIBCXX_END_NAMESPACE + +#ifndef _GLIBCXX_EXPORT_TEMPLATE +#include <bits/basic_ios.tcc> +#endif + +#endif /* _BASIC_IOS_H */ |