1 // Iostreams base classes -*- C++ -*- 2 3 // Copyright (C) 1997-2018 Free Software Foundation, Inc. 4 // 5 // This file is part of the GNU ISO C++ Library. This library is free 6 // software; you can redistribute it and/or modify it under the 7 // terms of the GNU General Public License as published by the 8 // Free Software Foundation; either version 3, or (at your option) 9 // any later version. 10 11 // This library is distributed in the hope that it will be useful, 12 // but WITHOUT ANY WARRANTY; without even the implied warranty of 13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 // GNU General Public License for more details. 15 16 // Under Section 7 of GPL version 3, you are granted additional 17 // permissions described in the GCC Runtime Library Exception, version 18 // 3.1, as published by the Free Software Foundation. 19 20 // You should have received a copy of the GNU General Public License and 21 // a copy of the GCC Runtime Library Exception along with this program; 22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 23 // <http://www.gnu.org/licenses/>. 24 25 // 26 // ISO C++ 14882: 27.4 Iostreams base classes 27 // 28 29 #include <ios> 30 #include <limits> 31 32 namespace std _GLIBCXX_VISIBILITY(default) 33 { 34 _GLIBCXX_BEGIN_NAMESPACE_VERSION 35 36 // Definitions for static const members of ios_base. 37 const ios_base::fmtflags ios_base::boolalpha; 38 const ios_base::fmtflags ios_base::dec; 39 const ios_base::fmtflags ios_base::fixed; 40 const ios_base::fmtflags ios_base::hex; 41 const ios_base::fmtflags ios_base::internal; 42 const ios_base::fmtflags ios_base::left; 43 const ios_base::fmtflags ios_base::oct; 44 const ios_base::fmtflags ios_base::right; 45 const ios_base::fmtflags ios_base::scientific; 46 const ios_base::fmtflags ios_base::showbase; 47 const ios_base::fmtflags ios_base::showpoint; 48 const ios_base::fmtflags ios_base::showpos; 49 const ios_base::fmtflags ios_base::skipws; 50 const ios_base::fmtflags ios_base::unitbuf; 51 const ios_base::fmtflags ios_base::uppercase; 52 const ios_base::fmtflags ios_base::adjustfield; 53 const ios_base::fmtflags ios_base::basefield; 54 const ios_base::fmtflags ios_base::floatfield; 55 56 const ios_base::iostate ios_base::badbit; 57 const ios_base::iostate ios_base::eofbit; 58 const ios_base::iostate ios_base::failbit; 59 const ios_base::iostate ios_base::goodbit; 60 61 const ios_base::openmode ios_base::app; 62 const ios_base::openmode ios_base::ate; 63 const ios_base::openmode ios_base::binary; 64 const ios_base::openmode ios_base::in; 65 const ios_base::openmode ios_base::out; 66 const ios_base::openmode ios_base::trunc; 67 68 const ios_base::seekdir ios_base::beg; 69 const ios_base::seekdir ios_base::cur; 70 const ios_base::seekdir ios_base::end; 71 72 _Atomic_word ios_base::Init::_S_refcount; 73 74 bool ios_base::Init::_S_synced_with_stdio = true; 75 ios_base()76 ios_base::ios_base() throw() 77 : _M_precision(), _M_width(), _M_flags(), _M_exception(), 78 _M_streambuf_state(), _M_callbacks(0), _M_word_zero(), 79 _M_word_size(_S_local_word_size), _M_word(_M_local_word), _M_ios_locale() 80 { 81 // Do nothing: basic_ios::init() does it. 82 // NB: _M_callbacks and _M_word must be zero for non-initialized 83 // ios_base to go through ~ios_base gracefully. 84 } 85 86 // 27.4.2.7 ios_base constructors/destructors ~ios_base()87 ios_base::~ios_base() 88 { 89 _M_call_callbacks(erase_event); 90 _M_dispose_callbacks(); 91 if (_M_word != _M_local_word) 92 { 93 delete [] _M_word; 94 _M_word = 0; 95 } 96 } 97 98 // 27.4.2.5 ios_base storage functions 99 int xalloc()100 ios_base::xalloc() throw() 101 { 102 // Implementation note: Initialize top to zero to ensure that 103 // initialization occurs before main() is started. 104 static _Atomic_word _S_top = 0; 105 return __gnu_cxx::__exchange_and_add_dispatch(&_S_top, 1) + 4; 106 } 107 108 void register_callback(event_callback __fn,int __index)109 ios_base::register_callback(event_callback __fn, int __index) 110 { _M_callbacks = new _Callback_list(__fn, __index, _M_callbacks); } 111 112 // 27.4.2.5 iword/pword storage 113 ios_base::_Words& _M_grow_words(int __ix,bool __iword)114 ios_base::_M_grow_words(int __ix, bool __iword) 115 { 116 // Precondition: _M_word_size <= __ix 117 int __newsize = _S_local_word_size; 118 _Words* __words = _M_local_word; 119 if (__ix > _S_local_word_size - 1) 120 { 121 if (__ix < numeric_limits<int>::max()) 122 { 123 __newsize = __ix + 1; 124 /* We still need to catch bad_alloc even though we use 125 a nothrow new, because the new-expression can throw 126 a bad_array_new_length. */ 127 __try 128 { __words = new (std::nothrow) _Words[__newsize]; } 129 __catch(const std::bad_alloc&) 130 { __words = nullptr; } 131 if (!__words) 132 { 133 _M_streambuf_state |= badbit; 134 if (_M_streambuf_state & _M_exception) 135 __throw_ios_failure(__N("ios_base::_M_grow_words " 136 "allocation failed")); 137 if (__iword) 138 _M_word_zero._M_iword = 0; 139 else 140 _M_word_zero._M_pword = 0; 141 return _M_word_zero; 142 } 143 for (int __i = 0; __i < _M_word_size; __i++) 144 __words[__i] = _M_word[__i]; 145 if (_M_word && _M_word != _M_local_word) 146 { 147 delete [] _M_word; 148 _M_word = 0; 149 } 150 } 151 else 152 { 153 _M_streambuf_state |= badbit; 154 if (_M_streambuf_state & _M_exception) 155 __throw_ios_failure(__N("ios_base::_M_grow_words is not valid")); 156 if (__iword) 157 _M_word_zero._M_iword = 0; 158 else 159 _M_word_zero._M_pword = 0; 160 return _M_word_zero; 161 } 162 } 163 _M_word = __words; 164 _M_word_size = __newsize; 165 return _M_word[__ix]; 166 } 167 168 void _M_call_callbacks(event __e)169 ios_base::_M_call_callbacks(event __e) throw() 170 { 171 _Callback_list* __p = _M_callbacks; 172 while (__p) 173 { 174 __try 175 { (*__p->_M_fn) (__e, *this, __p->_M_index); } 176 __catch(...) 177 { } 178 __p = __p->_M_next; 179 } 180 } 181 182 void _M_dispose_callbacks(void)183 ios_base::_M_dispose_callbacks(void) throw() 184 { 185 _Callback_list* __p = _M_callbacks; 186 while (__p && __p->_M_remove_reference() == 0) 187 { 188 _Callback_list* __next = __p->_M_next; 189 delete __p; 190 __p = __next; 191 } 192 _M_callbacks = 0; 193 } 194 195 void _M_move(ios_base & __rhs)196 ios_base::_M_move(ios_base& __rhs) noexcept 197 { 198 _M_precision = __rhs._M_precision; 199 _M_width = __rhs._M_width; 200 _M_flags = __rhs._M_flags; 201 _M_exception = __rhs._M_exception; 202 _M_streambuf_state = __rhs._M_streambuf_state; 203 _M_callbacks = std::__exchange(__rhs._M_callbacks, nullptr); 204 if (_M_word != _M_local_word) 205 delete[] _M_word; 206 if (__rhs._M_word == __rhs._M_local_word) 207 { 208 _M_word = _M_local_word; 209 _M_word_size = _S_local_word_size; 210 for (int __i = 0; __i < _S_local_word_size; __i++) 211 _M_word[__i] = std::__exchange(__rhs._M_word[__i], {}); 212 } 213 else 214 { 215 _M_word = std::__exchange(__rhs._M_word, __rhs._M_local_word); 216 _M_word_size 217 = std::__exchange(__rhs._M_word_size, _S_local_word_size); 218 } 219 _M_ios_locale = __rhs._M_ios_locale; 220 } 221 222 void _M_swap(ios_base & __rhs)223 ios_base::_M_swap(ios_base& __rhs) noexcept 224 { 225 std::swap(_M_precision, __rhs._M_precision); 226 std::swap(_M_width, __rhs._M_width); 227 std::swap(_M_flags, __rhs._M_flags); 228 std::swap(_M_exception, __rhs._M_exception); 229 std::swap(_M_streambuf_state, __rhs._M_streambuf_state); 230 std::swap(_M_callbacks, __rhs._M_callbacks); 231 const bool __lhs_local = _M_word == _M_local_word; 232 const bool __rhs_local = __rhs._M_word == __rhs._M_local_word; 233 if (__lhs_local && __rhs_local) 234 std::swap(_M_local_word, __rhs._M_local_word); // array swap 235 else 236 { 237 if (!__lhs_local && !__rhs_local) 238 std::swap(_M_word, __rhs._M_word); 239 else 240 { 241 ios_base* __local; 242 ios_base* __allocated; 243 if (__lhs_local) 244 { 245 __local = this; 246 __allocated = &__rhs; 247 } 248 else 249 { 250 __local = &__rhs; 251 __allocated= this; 252 } 253 for (int __i = 0; __i < _S_local_word_size; __i++) 254 __allocated->_M_local_word[__i] = __local->_M_local_word[__i]; 255 __local->_M_word = __allocated->_M_word; 256 __allocated->_M_word = __allocated->_M_local_word; 257 } 258 std::swap(_M_word_size, __rhs._M_word_size); 259 } 260 std::swap(_M_ios_locale, __rhs._M_ios_locale); 261 } 262 263 _GLIBCXX_END_NAMESPACE_VERSION 264 } // namespace 265