include/wx/scopedarray.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        wx/scopedarray.h
   3 // Purpose:     scoped smart pointer class
   4 // Author:      Vadim Zeitlin
   5 // Created:     2009-02-03
   6 // RCS-ID:      $Id$
   7 // Copyright:   (c) Jesse Lovelace and original Boost authors (see below)
   8 //              (c) 2009 Vadim Zeitlin
   9 // Licence:     wxWindows licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 #ifndef _WX_SCOPED_ARRAY_H_
  13 #define _WX_SCOPED_ARRAY_H_
  14
  15 #include "wx/defs.h"
  16 #include "wx/checkeddelete.h"
  17
  18 // ----------------------------------------------------------------------------
  19 // wxScopedArray: A scoped array
  20 // ----------------------------------------------------------------------------
  21
  22 template <class T>
  23 class wxScopedArray
  24 {
  25 public:
  26     typedef T element_type;
  27
  28     wxEXPLICIT wxScopedArray(T * array = NULL) : m_array(array) { }
  29
  30     ~wxScopedArray() { delete [] m_array; }
  31
  32     // test for pointer validity: defining conversion to unspecified_bool_type
  33     // and not more obvious bool to avoid implicit conversions to integer types
  34     typedef T *(wxScopedArray<T>::*unspecified_bool_type)() const;
  35     operator unspecified_bool_type() const
  36     {
  37         return m_array ? &wxScopedArray<T>::get : NULL;
  38     }
  39
  40     void reset(T *array = NULL)
  41     {
  42         if ( array != m_array )
  43         {
  44             delete [] m_array;
  45             m_array = array;
  46         }
  47     }
  48
  49     T& operator[](size_t n) const { return m_array[n]; }
  50
  51     T *get() const { return m_array; }
  52
  53     void swap(wxScopedArray &other)
  54     {
  55         T * const tmp = other.m_array;
  56         other.m_array = m_array;
  57         m_array = tmp;
  58     }
  59
  60 private:
  61     T *m_array;
  62
  63     DECLARE_NO_COPY_TEMPLATE_CLASS(wxScopedArray, T)
  64 };
  65
  66 // ----------------------------------------------------------------------------
  67 // old macro based implementation
  68 // ----------------------------------------------------------------------------
  69
  70 // the same but for arrays instead of simple pointers
  71 #define wxDECLARE_SCOPED_ARRAY(T, name)\
  72 class name                          \
  73 {                                   \
  74 private:                            \
  75     T * m_ptr;                      \
  76     name(name const &);             \
  77     name & operator=(name const &); \
  78                                     \
  79 public:                             \
  80     wxEXPLICIT name(T * p = NULL) : m_ptr(p) \
  81     {}                              \
  82                                     \
  83     ~name();                        \
  84     void reset(T * p = NULL);       \
  85                                     \
  86     T & operator[](long int i) const\
  87     {                               \
  88         wxASSERT(m_ptr != NULL);    \
  89         wxASSERT(i >= 0);           \
  90         return m_ptr[i];            \
  91     }                               \
  92                                     \
  93     T * get() const                 \
  94     {                               \
  95         return m_ptr;               \
  96     }                               \
  97                                     \
  98     void swap(name & ot)            \
  99     {                               \
 100         T * tmp = ot.m_ptr;         \
 101         ot.m_ptr = m_ptr;           \
 102         m_ptr = tmp;                \
 103     }                               \
 104 };
 105
 106 #define wxDEFINE_SCOPED_ARRAY(T, name)  \
 107 name::~name()                           \
 108 {                                       \
 109     wxCHECKED_DELETE_ARRAY(m_ptr);      \
 110 }                                       \
 111 void name::reset(T * p){                \
 112     if (m_ptr != p)                     \
 113     {                                   \
 114        wxCHECKED_DELETE_ARRAY(m_ptr);   \
 115        m_ptr = p;                       \
 116     }                                   \
 117 }
 118
 119 #endif // _WX_SCOPED_ARRAY_H_
 120