include/wx/ptr_scpd.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        wx/ptr_scpd.h
   3 // Purpose:     scoped smart pointer class
   4 // Author:      Jesse Lovelace <jllovela@eos.ncsu.edu>
   5 // Modified by:
   6 // Created:     06/01/02
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Jesse Lovelace and original Boost authors (see below)
   9 // Licence:     wxWindows license
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 //  This class closely follows the implementation of the boost
  13 //  library scoped_ptr and is an adaption for c++ macro's in
  14 //  the wxWindows project. The original authors of the boost
  15 //  scoped_ptr are given below with their respective copyrights.
  16
  17 //  (C) Copyright Greg Colvin and Beman Dawes 1998, 1999.
  18 //  Copyright (c) 2001, 2002 Peter Dimov
  19 //
  20 //  Permission to copy, use, modify, sell and distribute this software
  21 //  is granted provided this copyright notice appears in all copies.
  22 //  This software is provided "as is" without express or implied
  23 //  warranty, and with no claim as to its suitability for any purpose.
  24 //
  25 //  See http://www.boost.org/libs/smart_ptr/scoped_ptr.htm for documentation.
  26 //
  27
  28 #ifndef __WX_SCOPED_POINTER__
  29 #define __WX_SCOPED_POINTER__
  30
  31 #include "wx/defs.h"
  32
  33 /* checked deleters are used to make sure that the
  34    type being deleted is really a complete type.
  35    - Jesse Lovelace <jllovela@eos.ncsu.edu>
  36 */
  37
  38 #define wxCHECKED_DELETE(ptr)                \
  39     if (true) {                                 \
  40         typedef char complete[sizeof(*ptr)]; \
  41         delete ptr;                          \
  42     }
  43
  44 #define wxCHECKED_DELETE_ARRAY(ptr)          \
  45     if (true) {                                        \
  46         typedef char complete[sizeof(*ptr)]; \
  47         delete [] ptr;                       \
  48     }
  49
  50 /* These scoped pointers are *not* assignable and cannot be used
  51    within a container.  Look for wxDECLARE_SHARED_PTR for this
  52    functionality.
  53
  54    In addition, the type being used *must* be complete at the time
  55    that wxDEFINE_SCOPED_* is called or a compiler error will result.
  56    This is because the class checks for the completeness of the type
  57    being used.
  58 */
  59
  60
  61 #define wxDECLARE_SCOPED_PTR(T, name) \
  62 class name                          \
  63 {                                   \
  64 private:                            \
  65     T * m_ptr;                      \
  66                                     \
  67     name(name const &);             \
  68     name & operator=(name const &); \
  69                                     \
  70 public:                             \
  71     wxEXPLICIT name(T * ptr = NULL)  \
  72     : m_ptr(ptr) { }                \
  73                                     \
  74     ~name();                        \
  75                                     \
  76     void reset(T * ptr = NULL)      \
  77     {                               \
  78         if (m_ptr != ptr)           \
  79         {                           \
  80             delete m_ptr;           \
  81             m_ptr = ptr;            \
  82         }                           \
  83     }                               \
  84                                     \
  85     T & operator*() const           \
  86     {                               \
  87         wxASSERT(m_ptr != NULL);    \
  88         return *m_ptr;              \
  89     }                               \
  90                                     \
  91     T * operator->() const          \
  92     {                               \
  93         wxASSERT(m_ptr != NULL);    \
  94         return m_ptr;               \
  95     }                               \
  96                                     \
  97     T * get() const                 \
  98     {                               \
  99         return m_ptr;               \
 100     }                               \
 101                                     \
 102     void swap(name & ot)            \
 103     {                               \
 104         T * tmp = ot.m_ptr;         \
 105         ot.m_ptr = m_ptr;           \
 106         m_ptr = tmp;                \
 107     }                               \
 108 };
 109
 110 #define wxDEFINE_SCOPED_PTR(T, name)\
 111 name::~name()                       \
 112 {                                   \
 113     wxCHECKED_DELETE(m_ptr)      \
 114 }
 115
 116 #define wxDECLARE_SCOPED_ARRAY(T, name)\
 117 class name                          \
 118 {                                   \
 119 private:                            \
 120     T * m_ptr;                      \
 121     name(name const &);             \
 122     name & operator=(name const &); \
 123                                     \
 124 public:                             \
 125     wxEXPLICIT name(T * p = NULL) : m_ptr(p) \
 126     {}                              \
 127                                     \
 128     ~name();                        \
 129     void reset(T * p = NULL);       \
 130                                     \
 131     T & operator[](long int i) const\
 132     {                               \
 133         wxASSERT(m_ptr != NULL);    \
 134         wxASSERT(i >= 0);           \
 135         return m_ptr[i];            \
 136     }                               \
 137                                     \
 138     T * get() const                 \
 139     {                               \
 140         return m_ptr;               \
 141     }                               \
 142                                     \
 143     void swap(name & ot)            \
 144     {                               \
 145         T * tmp = ot.m_ptr;         \
 146         ot.m_ptr = m_ptr;           \
 147         m_ptr = tmp;                \
 148     }                               \
 149 };
 150
 151 #define wxDEFINE_SCOPED_ARRAY(T, name)  \
 152 name::~name()                       \
 153 {                                   \
 154     wxCHECKED_DELETE_ARRAY(m_ptr)  \
 155 }                                   \
 156 void name::reset(T * p){            \
 157     if (m_ptr != p)                 \
 158     {                               \
 159        wxCHECKED_DELETE_ARRAY(m_ptr); \
 160        m_ptr = p;                   \
 161     }                               \
 162 }
 163
 164 #endif