interpretor/preprocessor/faust-0.9.47mr3/compiler/headers/smartpointer.hh

   1 /************************************************************************
   2  ************************************************************************
   3     FAUST compiler
   4         Copyright (C) 2003-2004 GRAME, Centre National de Creation Musicale
   5     ---------------------------------------------------------------------
   6     This program is free software; you can redistribute it and/or modify
   7     it under the terms of the GNU General Public License as published by
   8     the Free Software Foundation; either version 2 of the License, or
   9     (at your option) any later version.
  10
  11     This program 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
  17     along with this program; if not, write to the Free Software
  18     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19  ************************************************************************
  20  ************************************************************************/
  21
  22
  23
  24 #ifndef _SMARTPOINTER_H
  25 #define _SMARTPOINTER_H
  26
  27 //#include <iostream>
  28 #include <cstdlib>
  29 #include <cstdio>
  30
  31
  32
  33 template<class T>
  34 class P {
  35         private:
  36                 T* p;
  37         public:
  38                 P()     : p(0)                                                  { }
  39                 P(T* rawptr) : p(rawptr)                        { }
  40                 P(const P& ptr) : p((T*)ptr)            { }
  41
  42                 template<class T2>
  43                 P(const P<T2>& ptr) : p((T*)ptr)        { }
  44
  45                 ~P()                                                            { }
  46
  47                 operator T*() const                                     { return p;     }
  48                 T& operator*() const {
  49                         if (p == 0) {
  50                                 //throw std::runtime_error("Null dereference in P<?>::operator*() const ");
  51                                 fprintf(stderr, "Null dereference in P<?>::operator*() const \n ");
  52                                 exit(1);
  53                         }
  54                         return *p;
  55                 }
  56                 T* operator->() const   {
  57                         if (p == 0) {
  58                                 fprintf(stderr, "Null dereference in P<?>::operator->() const \n ");
  59                                 //throw std::runtime_error("Null dereference in P<?>::operator->() const ");
  60                                 //std::cerr << "Null dereference in P<?>::operator->() const " << std::endl;
  61                                 exit(1);
  62                         }
  63                         return p;
  64                 }
  65                 T* pointee() const      { return p;}
  66                 P& operator=(T* p_)     { p = p_;  return *this;}
  67
  68                 P& operator=(const P<T>& p_)            { return operator=((T *) p_); }
  69                 template<class T2> P& cast(T2* p_)      { return operator=(dynamic_cast<T*>(p_)); }
  70                 template<class T2> P& cast(const P<T2>& p_) { return operator=(dynamic_cast<T*>(p_)); }
  71 };
  72
  73
  74 #endif