// wstring_convert implementation -*- C++ -*- // Copyright (C) 2015-2018 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/locale_conv.h * This is an internal header file, included by other library headers. * Do not attempt to use it directly. @headername{locale} */ #ifndef _LOCALE_CONV_H #define _LOCALE_CONV_H 1 #if __cplusplus < 201103L # include <bits/c++0x_warning.h> #else #include <streambuf> #include <bits/stringfwd.h> #include <bits/allocator.h> #include <bits/codecvt.h> #include <bits/unique_ptr.h> namespace std _GLIBCXX_VISIBILITY(default) { _GLIBCXX_BEGIN_NAMESPACE_VERSION /** * @addtogroup locales * @{ */ template<typename _OutStr, typename _InChar, typename _Codecvt, typename _State, typename _Fn> bool __do_str_codecvt(const _InChar* __first, const _InChar* __last, _OutStr& __outstr, const _Codecvt& __cvt, _State& __state, size_t& __count, _Fn __fn) { if (__first == __last) { __outstr.clear(); __count = 0; return true; } size_t __outchars = 0; auto __next = __first; const auto __maxlen = __cvt.max_length() + 1; codecvt_base::result __result; do { __outstr.resize(__outstr.size() + (__last - __next) * __maxlen); auto __outnext = &__outstr.front() + __outchars; auto const __outlast = &__outstr.back() + 1; __result = (__cvt.*__fn)(__state, __next, __last, __next, __outnext, __outlast, __outnext); __outchars = __outnext - &__outstr.front(); } while (__result == codecvt_base::partial && __next != __last && (__outstr.size() - __outchars) < __maxlen); if (__result == codecvt_base::error) { __count = __next - __first; return false; } if (__result == codecvt_base::noconv) { __outstr.assign(__first, __last); __count = __last - __first; } else { __outstr.resize(__outchars); __count = __next - __first; } return true; } // Convert narrow character string to wide. template<typename _CharT, typename _Traits, typename _Alloc, typename _State> inline bool __str_codecvt_in(const char* __first, const char* __last, basic_string<_CharT, _Traits, _Alloc>& __outstr, const codecvt<_CharT, char, _State>& __cvt, _State& __state, size_t& __count) { using _Codecvt = codecvt<_CharT, char, _State>; using _ConvFn = codecvt_base::result (_Codecvt::*)(_State&, const char*, const char*, const char*&, _CharT*, _CharT*, _CharT*&) const; _ConvFn __fn = &codecvt<_CharT, char, _State>::in; return __do_str_codecvt(__first, __last, __outstr, __cvt, __state, __count, __fn); } template<typename _CharT, typename _Traits, typename _Alloc, typename _State> inline bool __str_codecvt_in(const char* __first, const char* __last, basic_string<_CharT, _Traits, _Alloc>& __outstr, const codecvt<_CharT, char, _State>& __cvt) { _State __state = {}; size_t __n; return __str_codecvt_in(__first, __last, __outstr, __cvt, __state, __n); } // Convert wide character string to narrow. template<typename _CharT, typename _Traits, typename _Alloc, typename _State> inline bool __str_codecvt_out(const _CharT* __first, const _CharT* __last, basic_string<char, _Traits, _Alloc>& __outstr, const codecvt<_CharT, char, _State>& __cvt, _State& __state, size_t& __count) { using _Codecvt = codecvt<_CharT, char, _State>; using _ConvFn = codecvt_base::result (_Codecvt::*)(_State&, const _CharT*, const _CharT*, const _CharT*&, char*, char*, char*&) const; _ConvFn __fn = &codecvt<_CharT, char, _State>::out; return __do_str_codecvt(__first, __last, __outstr, __cvt, __state, __count, __fn); } template<typename _CharT, typename _Traits, typename _Alloc, typename _State> inline bool __str_codecvt_out(const _CharT* __first, const _CharT* __last, basic_string<char, _Traits, _Alloc>& __outstr, const codecvt<_CharT, char, _State>& __cvt) { _State __state = {}; size_t __n; return __str_codecvt_out(__first, __last, __outstr, __cvt, __state, __n); } #ifdef _GLIBCXX_USE_WCHAR_T _GLIBCXX_BEGIN_NAMESPACE_CXX11 /// String conversions template<typename _Codecvt, typename _Elem = wchar_t, typename _Wide_alloc = allocator<_Elem>, typename _Byte_alloc = allocator<char>> class wstring_convert { public: typedef basic_string<char, char_traits<char>, _Byte_alloc> byte_string; typedef basic_string<_Elem, char_traits<_Elem>, _Wide_alloc> wide_string; typedef typename _Codecvt::state_type state_type; typedef typename wide_string::traits_type::int_type int_type; /** Default constructor. * * @param __pcvt The facet to use for conversions. * * Takes ownership of @p __pcvt and will delete it in the destructor. */ explicit wstring_convert(_Codecvt* __pcvt = new _Codecvt()) : _M_cvt(__pcvt) { if (!_M_cvt) __throw_logic_error("wstring_convert"); } /** Construct with an initial converstion state. * * @param __pcvt The facet to use for conversions. * @param __state Initial conversion state. * * Takes ownership of @p __pcvt and will delete it in the destructor. * The object's conversion state will persist between conversions. */ wstring_convert(_Codecvt* __pcvt, state_type __state) : _M_cvt(__pcvt), _M_state(__state), _M_with_cvtstate(true) { if (!_M_cvt) __throw_logic_error("wstring_convert"); } /** Construct with error strings. * * @param __byte_err A string to return on failed conversions. * @param __wide_err A wide string to return on failed conversions. */ explicit wstring_convert(const byte_string& __byte_err, const wide_string& __wide_err = wide_string()) : _M_cvt(new _Codecvt), _M_byte_err_string(__byte_err), _M_wide_err_string(__wide_err), _M_with_strings(true) { if (!_M_cvt) __throw_logic_error("wstring_convert"); } ~wstring_convert() = default; // _GLIBCXX_RESOLVE_LIB_DEFECTS // 2176. Special members for wstring_convert and wbuffer_convert wstring_convert(const wstring_convert&) = delete; wstring_convert& operator=(const wstring_convert&) = delete; /// @{ Convert from bytes. wide_string from_bytes(char __byte) { char __bytes[2] = { __byte }; return from_bytes(__bytes, __bytes+1); } wide_string from_bytes(const char* __ptr) { return from_bytes(__ptr, __ptr+char_traits<char>::length(__ptr)); } wide_string from_bytes(const byte_string& __str) { auto __ptr = __str.data(); return from_bytes(__ptr, __ptr + __str.size()); } wide_string from_bytes(const char* __first, const char* __last) { if (!_M_with_cvtstate) _M_state = state_type(); wide_string __out{ _M_wide_err_string.get_allocator() }; if (__str_codecvt_in(__first, __last, __out, *_M_cvt, _M_state, _M_count)) return __out; if (_M_with_strings) return _M_wide_err_string; __throw_range_error("wstring_convert::from_bytes"); } /// @} /// @{ Convert to bytes. byte_string to_bytes(_Elem __wchar) { _Elem __wchars[2] = { __wchar }; return to_bytes(__wchars, __wchars+1); } byte_string to_bytes(const _Elem* __ptr) { return to_bytes(__ptr, __ptr+wide_string::traits_type::length(__ptr)); } byte_string to_bytes(const wide_string& __wstr) { auto __ptr = __wstr.data(); return to_bytes(__ptr, __ptr + __wstr.size()); } byte_string to_bytes(const _Elem* __first, const _Elem* __last) { if (!_M_with_cvtstate) _M_state = state_type(); byte_string __out{ _M_byte_err_string.get_allocator() }; if (__str_codecvt_out(__first, __last, __out, *_M_cvt, _M_state, _M_count)) return __out; if (_M_with_strings) return _M_byte_err_string; __throw_range_error("wstring_convert::to_bytes"); } /// @} // _GLIBCXX_RESOLVE_LIB_DEFECTS // 2174. wstring_convert::converted() should be noexcept /// The number of elements successfully converted in the last conversion. size_t converted() const noexcept { return _M_count; } /// The final conversion state of the last conversion. state_type state() const { return _M_state; } private: unique_ptr<_Codecvt> _M_cvt; byte_string _M_byte_err_string; wide_string _M_wide_err_string; state_type _M_state = state_type(); size_t _M_count = 0; bool _M_with_cvtstate = false; bool _M_with_strings = false; }; _GLIBCXX_END_NAMESPACE_CXX11 /// Buffer conversions template<typename _Codecvt, typename _Elem = wchar_t, typename _Tr = char_traits<_Elem>> class wbuffer_convert : public basic_streambuf<_Elem, _Tr> { typedef basic_streambuf<_Elem, _Tr> _Wide_streambuf; public: typedef typename _Codecvt::state_type state_type; /** Default constructor. * * @param __bytebuf The underlying byte stream buffer. * @param __pcvt The facet to use for conversions. * @param __state Initial conversion state. * * Takes ownership of @p __pcvt and will delete it in the destructor. */ explicit wbuffer_convert(streambuf* __bytebuf = 0, _Codecvt* __pcvt = new _Codecvt, state_type __state = state_type()) : _M_buf(__bytebuf), _M_cvt(__pcvt), _M_state(__state) { if (!_M_cvt) __throw_logic_error("wbuffer_convert"); _M_always_noconv = _M_cvt->always_noconv(); if (_M_buf) { this->setp(_M_put_area, _M_put_area + _S_buffer_length); this->setg(_M_get_area + _S_putback_length, _M_get_area + _S_putback_length, _M_get_area + _S_putback_length); } } ~wbuffer_convert() = default; // _GLIBCXX_RESOLVE_LIB_DEFECTS // 2176. Special members for wstring_convert and wbuffer_convert wbuffer_convert(const wbuffer_convert&) = delete; wbuffer_convert& operator=(const wbuffer_convert&) = delete; streambuf* rdbuf() const noexcept { return _M_buf; } streambuf* rdbuf(streambuf *__bytebuf) noexcept { auto __prev = _M_buf; _M_buf = __bytebuf; return __prev; } /// The conversion state following the last conversion. state_type state() const noexcept { return _M_state; } protected: int sync() { return _M_buf && _M_conv_put() && !_M_buf->pubsync() ? 0 : -1; } typename _Wide_streambuf::int_type overflow(typename _Wide_streambuf::int_type __out) { if (!_M_buf || !_M_conv_put()) return _Tr::eof(); else if (!_Tr::eq_int_type(__out, _Tr::eof())) return this->sputc(__out); return _Tr::not_eof(__out); } typename _Wide_streambuf::int_type underflow() { if (!_M_buf) return _Tr::eof(); if (this->gptr() < this->egptr() || (_M_buf && _M_conv_get())) return _Tr::to_int_type(*this->gptr()); else return _Tr::eof(); } streamsize xsputn(const typename _Wide_streambuf::char_type* __s, streamsize __n) { if (!_M_buf || __n == 0) return 0; streamsize __done = 0; do { auto __nn = std::min<streamsize>(this->epptr() - this->pptr(), __n - __done); _Tr::copy(this->pptr(), __s + __done, __nn); this->pbump(__nn); __done += __nn; } while (__done < __n && _M_conv_put()); return __done; } private: // fill the get area from converted contents of the byte stream buffer bool _M_conv_get() { const streamsize __pb1 = this->gptr() - this->eback(); const streamsize __pb2 = _S_putback_length; const streamsize __npb = std::min(__pb1, __pb2); _Tr::move(_M_get_area + _S_putback_length - __npb, this->gptr() - __npb, __npb); streamsize __nbytes = sizeof(_M_get_buf) - _M_unconv; __nbytes = std::min(__nbytes, _M_buf->in_avail()); if (__nbytes < 1) __nbytes = 1; __nbytes = _M_buf->sgetn(_M_get_buf + _M_unconv, __nbytes); if (__nbytes < 1) return false; __nbytes += _M_unconv; // convert _M_get_buf into _M_get_area _Elem* __outbuf = _M_get_area + _S_putback_length; _Elem* __outnext = __outbuf; const char* __bnext = _M_get_buf; codecvt_base::result __result; if (_M_always_noconv) __result = codecvt_base::noconv; else { _Elem* __outend = _M_get_area + _S_buffer_length; __result = _M_cvt->in(_M_state, __bnext, __bnext + __nbytes, __bnext, __outbuf, __outend, __outnext); } if (__result == codecvt_base::noconv) { // cast is safe because noconv means _Elem is same type as char auto __get_buf = reinterpret_cast<const _Elem*>(_M_get_buf); _Tr::copy(__outbuf, __get_buf, __nbytes); _M_unconv = 0; return true; } if ((_M_unconv = _M_get_buf + __nbytes - __bnext)) char_traits<char>::move(_M_get_buf, __bnext, _M_unconv); this->setg(__outbuf, __outbuf, __outnext); return __result != codecvt_base::error; } // unused bool _M_put(...) { return false; } bool _M_put(const char* __p, streamsize __n) { if (_M_buf->sputn(__p, __n) < __n) return false; return true; } // convert the put area and write to the byte stream buffer bool _M_conv_put() { _Elem* const __first = this->pbase(); const _Elem* const __last = this->pptr(); const streamsize __pending = __last - __first; if (_M_always_noconv) return _M_put(__first, __pending); char __outbuf[2 * _S_buffer_length]; const _Elem* __next = __first; const _Elem* __start; do { __start = __next; char* __outnext = __outbuf; char* const __outlast = __outbuf + sizeof(__outbuf); auto __result = _M_cvt->out(_M_state, __next, __last, __next, __outnext, __outlast, __outnext); if (__result == codecvt_base::error) return false; else if (__result == codecvt_base::noconv) return _M_put(__next, __pending); if (!_M_put(__outbuf, __outnext - __outbuf)) return false; } while (__next != __last && __next != __start); if (__next != __last) _Tr::move(__first, __next, __last - __next); this->pbump(__first - __next); return __next != __first; } streambuf* _M_buf; unique_ptr<_Codecvt> _M_cvt; state_type _M_state; static const streamsize _S_buffer_length = 32; static const streamsize _S_putback_length = 3; _Elem _M_put_area[_S_buffer_length]; _Elem _M_get_area[_S_buffer_length]; streamsize _M_unconv = 0; char _M_get_buf[_S_buffer_length-_S_putback_length]; bool _M_always_noconv; }; #endif // _GLIBCXX_USE_WCHAR_T /// @} group locales _GLIBCXX_END_NAMESPACE_VERSION } // namespace #endif // __cplusplus #endif /* _LOCALE_CONV_H */