libvspell/boost/scoped_ptr.hpp

   1 #ifndef BOOST_SCOPED_PTR_HPP_INCLUDED
   2 #define BOOST_SCOPED_PTR_HPP_INCLUDED
   3
   4 //  (C) Copyright Greg Colvin and Beman Dawes 1998, 1999.
   5 //  Copyright (c) 2001, 2002 Peter Dimov
   6 //
   7 //  Permission to copy, use, modify, sell and distribute this software
   8 //  is granted provided this copyright notice appears in all copies.
   9 //  This software is provided "as is" without express or implied
  10 //  warranty, and with no claim as to its suitability for any purpose.
  11 //
  12 //  See http://www.boost.org/libs/smart_ptr/scoped_ptr.htm for documentation.
  13 //
  14
  15 #include <boost/assert.hpp>
  16 #include <boost/checked_delete.hpp>
  17
  18 #ifndef BOOST_NO_AUTO_PTR
  19 # include <memory>          // for std::auto_ptr
  20 #endif
  21
  22 namespace boost
  23 {
  24
  25 //  scoped_ptr mimics a built-in pointer except that it guarantees deletion
  26 //  of the object pointed to, either on destruction of the scoped_ptr or via
  27 //  an explicit reset(). scoped_ptr is a simple solution for simple needs;
  28 //  use shared_ptr or std::auto_ptr if your needs are more complex.
  29
  30 template<typename T> class scoped_ptr // noncopyable
  31 {
  32 private:
  33
  34     T * ptr;
  35
  36     scoped_ptr(scoped_ptr const &);
  37     scoped_ptr & operator=(scoped_ptr const &);
  38
  39     typedef scoped_ptr<T> this_type;
  40
  41 public:
  42
  43     typedef T element_type;
  44
  45     explicit scoped_ptr(T * p = 0): ptr(p) // never throws
  46     {
  47     }
  48
  49 #ifndef BOOST_NO_AUTO_PTR
  50
  51     explicit scoped_ptr(std::auto_ptr<T> p): ptr(p.release()) // never throws
  52     {
  53     }
  54
  55 #endif
  56
  57     ~scoped_ptr() // never throws
  58     {
  59         checked_delete(ptr);
  60     }
  61
  62     void reset(T * p = 0) // never throws
  63     {
  64         if(ptr != p)
  65         {
  66             this_type(p).swap(*this);
  67         }
  68     }
  69
  70     T & operator*() const // never throws
  71     {
  72         BOOST_ASSERT(ptr != 0);
  73         return *ptr;
  74     }
  75
  76     T * operator->() const // never throws
  77     {
  78         BOOST_ASSERT(ptr != 0);
  79         return ptr;
  80     }
  81
  82     T * get() const // never throws
  83     {
  84         return ptr;
  85     }
  86
  87     // implicit conversion to "bool"
  88
  89     typedef T * (this_type::*unspecified_bool_type)() const;
  90
  91     operator unspecified_bool_type() const // never throws
  92     {
  93         return ptr == 0? 0: &this_type::get;
  94     }
  95
  96     bool operator! () const // never throws
  97     {
  98         return ptr == 0;
  99     }
 100
 101     void swap(scoped_ptr & b) // never throws
 102     {
 103         T * tmp = b.ptr;
 104         b.ptr = ptr;
 105         ptr = tmp;
 106     }
 107 };
 108
 109 template<typename T> inline void swap(scoped_ptr<T> & a, scoped_ptr<T> & b) // never throws
 110 {
 111     a.swap(b);
 112 }
 113
 114 // get_pointer(p) is a generic way to say p.get()
 115
 116 template<typename T> inline T * get_pointer(scoped_ptr<T> const & p)
 117 {
 118     return p.get();
 119 }
 120
 121 } // namespace boost
 122
 123 #endif // #ifndef BOOST_SCOPED_PTR_HPP_INCLUDED