1 // The template and inlines for the -*- C++ -*- gslice class. 2 3 // Copyright (C) 1997, 1998, 1999, 2000, 2001 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 // Written by Gabriel Dos Reis <Gabriel.Dos-Reis@DPTMaths.ENS-Cachan.Fr> 31 32 /** @file gslice.h 33 * This is an internal header file, included by other library headers. 34 * You should not attempt to use it directly. 35 */ 36 37 #ifndef _CPP_BITS_GSLICE_H 38 #define _CPP_BITS_GSLICE_H 1 39 40 #pragma GCC system_header 41 42 namespace std { 43 44 class gslice 45 { 46 public: 47 gslice (); 48 gslice (size_t, const valarray<size_t>&, const valarray<size_t>&); 49 // XXX: the IS says the copy-ctor and copy-assignment operators are 50 // synthetized by the compiler but they are just unsuitable 51 // for a ref-counted semantic 52 gslice(const gslice&); 53 ~gslice(); 54 55 // XXX: See the note above. 56 gslice& operator= (const gslice&); 57 58 size_t start () const; 59 valarray<size_t> size () const; 60 valarray<size_t> stride () const; 61 62 private: 63 struct _Indexer { 64 size_t _M_count; 65 size_t _M_start; 66 valarray<size_t> _M_size; 67 valarray<size_t> _M_stride; 68 valarray<size_t> _M_index; 69 _Indexer(size_t, const valarray<size_t>&, 70 const valarray<size_t>&); _M_increment_use_Indexer71 void _M_increment_use() { ++_M_count; } _M_decrement_use_Indexer72 size_t _M_decrement_use() { return --_M_count; } 73 }; 74 75 _Indexer* _M_index; 76 77 template<typename _Tp> friend class valarray; 78 }; 79 80 inline size_t start()81 gslice::start () const 82 { return _M_index ? _M_index->_M_start : 0; } 83 84 inline valarray<size_t> size()85 gslice::size () const 86 { return _M_index ? _M_index->_M_size : valarray<size_t>(); } 87 88 inline valarray<size_t> stride()89 gslice::stride () const 90 { return _M_index ? _M_index->_M_stride : valarray<size_t>(); } 91 gslice()92 inline gslice::gslice () : _M_index(0) {} 93 94 inline gslice(size_t __o,const valarray<size_t> & __l,const valarray<size_t> & __s)95 gslice::gslice(size_t __o, const valarray<size_t>& __l, 96 const valarray<size_t>& __s) 97 : _M_index(new gslice::_Indexer(__o, __l, __s)) {} 98 99 inline gslice(const gslice & __g)100 gslice::gslice(const gslice& __g) : _M_index(__g._M_index) 101 { if (_M_index) _M_index->_M_increment_use(); } 102 103 inline ~gslice()104 gslice::~gslice() 105 { if (_M_index && _M_index->_M_decrement_use() == 0) delete _M_index; } 106 107 inline gslice& 108 gslice::operator= (const gslice& __g) 109 { 110 if (__g._M_index) __g._M_index->_M_increment_use(); 111 if (_M_index && _M_index->_M_decrement_use() == 0) delete _M_index; 112 _M_index = __g._M_index; 113 return *this; 114 } 115 116 117 } // std:: 118 119 120 #endif /* _CPP_BITS_GSLICE_H */ 121 122 // Local Variables: 123 // mode:c++ 124 // End: 125