1 // Temporary buffer implementation -*- C++ -*- 2 3 // Copyright (C) 2001, 2002 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 2, 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 // You should have received a copy of the GNU General Public License along 17 // with this library; see the file COPYING. If not, write to the Free 18 // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, 19 // USA. 20 21 // As a special exception, you may use this file as part of a free software 22 // library without restriction. Specifically, if other files instantiate 23 // templates or use macros or inline functions from this file, or you compile 24 // this file and link it with other files to produce an executable, this 25 // file does not by itself cause the resulting executable to be covered by 26 // the GNU General Public License. This exception does not however 27 // invalidate any other reasons why the executable file might be covered by 28 // the GNU General Public License. 29 30 /* 31 * 32 * Copyright (c) 1994 33 * Hewlett-Packard Company 34 * 35 * Permission to use, copy, modify, distribute and sell this software 36 * and its documentation for any purpose is hereby granted without fee, 37 * provided that the above copyright notice appear in all copies and 38 * that both that copyright notice and this permission notice appear 39 * in supporting documentation. Hewlett-Packard Company makes no 40 * representations about the suitability of this software for any 41 * purpose. It is provided "as is" without express or implied warranty. 42 * 43 * 44 * Copyright (c) 1996,1997 45 * Silicon Graphics Computer Systems, Inc. 46 * 47 * Permission to use, copy, modify, distribute and sell this software 48 * and its documentation for any purpose is hereby granted without fee, 49 * provided that the above copyright notice appear in all copies and 50 * that both that copyright notice and this permission notice appear 51 * in supporting documentation. Silicon Graphics makes no 52 * representations about the suitability of this software for any 53 * purpose. It is provided "as is" without express or implied warranty. 54 */ 55 56 /** @file stl_tempbuf.h 57 * This is an internal header file, included by other library headers. 58 * You should not attempt to use it directly. 59 */ 60 61 #ifndef __GLIBCPP_INTERNAL_TEMPBUF_H 62 #define __GLIBCPP_INTERNAL_TEMPBUF_H 63 64 namespace std 65 { 66 67 /** 68 * @if maint 69 * This class is used in two places: stl_algo.h and ext/memory, where it 70 * is wrapped as the temporary_buffer class. See temporary_buffer docs for 71 * more notes. 72 * @endif 73 */ 74 template <class _ForwardIterator, class _Tp> 75 class _Temporary_buffer 76 { 77 // concept requirements 78 __glibcpp_class_requires(_ForwardIterator, _ForwardIteratorConcept) 79 80 ptrdiff_t _M_original_len; 81 ptrdiff_t _M_len; 82 _Tp* _M_buffer; 83 84 // this is basically get_temporary_buffer() all over again _M_allocate_buffer()85 void _M_allocate_buffer() { 86 _M_original_len = _M_len; 87 _M_buffer = 0; 88 89 if (_M_len > (ptrdiff_t)(INT_MAX / sizeof(_Tp))) 90 _M_len = INT_MAX / sizeof(_Tp); 91 92 while (_M_len > 0) { 93 _M_buffer = (_Tp*) malloc(_M_len * sizeof(_Tp)); 94 if (_M_buffer) 95 break; 96 _M_len /= 2; 97 } 98 } 99 _M_initialize_buffer(const _Tp &,__true_type)100 void _M_initialize_buffer(const _Tp&, __true_type) {} _M_initialize_buffer(const _Tp & val,__false_type)101 void _M_initialize_buffer(const _Tp& val, __false_type) { 102 uninitialized_fill_n(_M_buffer, _M_len, val); 103 } 104 105 public: 106 /// As per Table mumble. size()107 ptrdiff_t size() const { return _M_len; } 108 /// Returns the size requested by the constructor; may be >size(). requested_size()109 ptrdiff_t requested_size() const { return _M_original_len; } 110 /// As per Table mumble. begin()111 _Tp* begin() { return _M_buffer; } 112 /// As per Table mumble. end()113 _Tp* end() { return _M_buffer + _M_len; } 114 _Temporary_buffer(_ForwardIterator __first,_ForwardIterator __last)115 _Temporary_buffer(_ForwardIterator __first, _ForwardIterator __last) { 116 // Workaround for a __type_traits bug in the pre-7.3 compiler. 117 typedef typename __type_traits<_Tp>::has_trivial_default_constructor 118 _Trivial; 119 120 try { 121 _M_len = distance(__first, __last); 122 _M_allocate_buffer(); 123 if (_M_len > 0) 124 _M_initialize_buffer(*__first, _Trivial()); 125 } 126 catch(...) 127 { 128 free(_M_buffer); 129 _M_buffer = 0; 130 _M_len = 0; 131 __throw_exception_again; 132 } 133 } 134 ~_Temporary_buffer()135 ~_Temporary_buffer() { 136 _Destroy(_M_buffer, _M_buffer + _M_len); 137 free(_M_buffer); 138 } 139 140 private: 141 // Disable copy constructor and assignment operator. _Temporary_buffer(const _Temporary_buffer &)142 _Temporary_buffer(const _Temporary_buffer&) {} 143 void operator=(const _Temporary_buffer&) {} 144 }; 145 146 } // namespace std 147 148 #endif /* __GLIBCPP_INTERNAL_TEMPBUF_H */ 149 150