00001 // The template and inlines for the -*- C++ -*- gslice class. 00002 00003 // Copyright (C) 1997, 1998, 1999, 2000, 2001 Free Software Foundation, Inc. 00004 // 00005 // This file is part of the GNU ISO C++ Library. This library is free 00006 // software; you can redistribute it and/or modify it under the 00007 // terms of the GNU General Public License as published by the 00008 // Free Software Foundation; either version 2, or (at your option) 00009 // any later version. 00010 00011 // This library is distributed in the hope that it will be useful, 00012 // but WITHOUT ANY WARRANTY; without even the implied warranty of 00013 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 00014 // GNU General Public License for more details. 00015 00016 // You should have received a copy of the GNU General Public License along 00017 // with this library; see the file COPYING. If not, write to the Free 00018 // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, 00019 // USA. 00020 00021 // As a special exception, you may use this file as part of a free software 00022 // library without restriction. Specifically, if other files instantiate 00023 // templates or use macros or inline functions from this file, or you compile 00024 // this file and link it with other files to produce an executable, this 00025 // file does not by itself cause the resulting executable to be covered by 00026 // the GNU General Public License. This exception does not however 00027 // invalidate any other reasons why the executable file might be covered by 00028 // the GNU General Public License. 00029 00030 // Written by Gabriel Dos Reis <Gabriel.Dos-Reis@DPTMaths.ENS-Cachan.Fr> 00031 00032 /** @file gslice.h 00033 * This is an internal header file, included by other library headers. 00034 * You should not attempt to use it directly. 00035 */ 00036 00037 #ifndef _CPP_BITS_GSLICE_H 00038 #define _CPP_BITS_GSLICE_H 1 00039 00040 #pragma GCC system_header 00041 00042 namespace std { 00043 00044 class gslice 00045 { 00046 public: 00047 gslice (); 00048 gslice (size_t, const valarray<size_t>&, const valarray<size_t>&); 00049 // XXX: the IS says the copy-ctor and copy-assignment operators are 00050 // synthetized by the compiler but they are just unsuitable 00051 // for a ref-counted semantic 00052 gslice(const gslice&); 00053 ~gslice(); 00054 00055 // XXX: See the note above. 00056 gslice& operator= (const gslice&); 00057 00058 size_t start () const; 00059 valarray<size_t> size () const; 00060 valarray<size_t> stride () const; 00061 00062 private: 00063 struct _Indexer { 00064 size_t _M_count; 00065 size_t _M_start; 00066 valarray<size_t> _M_size; 00067 valarray<size_t> _M_stride; 00068 valarray<size_t> _M_index; 00069 _Indexer(size_t, const valarray<size_t>&, 00070 const valarray<size_t>&); 00071 void _M_increment_use() { ++_M_count; } 00072 size_t _M_decrement_use() { return --_M_count; } 00073 }; 00074 00075 _Indexer* _M_index; 00076 00077 template<typename _Tp> friend class valarray; 00078 }; 00079 00080 inline size_t 00081 gslice::start () const 00082 { return _M_index ? _M_index->_M_start : 0; } 00083 00084 inline valarray<size_t> 00085 gslice::size () const 00086 { return _M_index ? _M_index->_M_size : valarray<size_t>(); } 00087 00088 inline valarray<size_t> 00089 gslice::stride () const 00090 { return _M_index ? _M_index->_M_stride : valarray<size_t>(); } 00091 00092 inline gslice::gslice () : _M_index(0) {} 00093 00094 inline 00095 gslice::gslice(size_t __o, const valarray<size_t>& __l, 00096 const valarray<size_t>& __s) 00097 : _M_index(new gslice::_Indexer(__o, __l, __s)) {} 00098 00099 inline 00100 gslice::gslice(const gslice& __g) : _M_index(__g._M_index) 00101 { if (_M_index) _M_index->_M_increment_use(); } 00102 00103 inline 00104 gslice::~gslice() 00105 { if (_M_index && _M_index->_M_decrement_use() == 0) delete _M_index; } 00106 00107 inline gslice& 00108 gslice::operator= (const gslice& __g) 00109 { 00110 if (__g._M_index) __g._M_index->_M_increment_use(); 00111 if (_M_index && _M_index->_M_decrement_use() == 0) delete _M_index; 00112 _M_index = __g._M_index; 00113 return *this; 00114 } 00115 00116 00117 } // std:: 00118 00119 00120 #endif /* _CPP_BITS_GSLICE_H */ 00121 00122 // Local Variables: 00123 // mode:c++ 00124 // End: