summaryrefslogtreecommitdiff
path: root/ACE/ace/Based_Pointer_T.h
blob: 33085713804bc201f20292055eb6d061ce229f21 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
// -*- C++ -*-

//=============================================================================
/**
 *  @file    Based_Pointer_T.h
 *
 *  @author Dietrich Quehl <Dietrich.Quehl@med.siemens.de>
 *  @author Douglas C. Schmidt <schmidt@.cs.wustl.edu>
 */
//=============================================================================

#ifndef ACE_BASED_POINTER_T_H
#define ACE_BASED_POINTER_T_H

#include /**/ "ace/pre.h"

#include /**/ "ace/config-all.h"
#include "ace/Basic_Types.h"

#if defined (_MSC_VER)
// Suppress warning e.g. "return type for
// 'ACE_Based_Pointer<long>::operator ->' is 'long *' (i.e., not a UDT
// or reference to a UDT.  Will produce errors if applied using infix
// notation)"
#pragma warning(disable: 4284)
#endif /* _MSC_VER */

ACE_BEGIN_VERSIONED_NAMESPACE_DECL

/**
 * @class ACE_Based_Pointer_Basic
 *
 * @brief A proxy that keeps track of the relative offset of a "pointer"
 * from its base address.
 * This class makes it possible to transparently use "pointers" in
 * shared memory as easily as programming with pointers to local
 * memory.  In particular, we don't need to ensure that the base
 * addresses of all the pointers are mapped into separate
 * processes at the same absolute memory base address.
 */
template <class CONCRETE>
class ACE_Based_Pointer_Basic
{
public:
  /**
   * This constructor initializes the <base_offset_> by asking the
   * <ACE_BASED_POINTER_REPOSITORY> Singleton for the base address of
   * the memory region within which it is instantiated.  Two results
   * are possible:
   *
   * 1. An <ACE_*_Memory_Pool> has stored a base address/size pair and the
   *    new based-pointer instance is located between the base address and
   *    the base address + size - 1.  In this case, the repository
   *    returns the base address.
   *
   * 2. No suitable address/size pair was found.  The repository
   *    assumes an address in the regular (not mapped) virtual address
   *    space of the process and returns 0.  In this case, the
   *    based-pointer uses its address as an offset to it's base
   *    address 0.
   */
  ACE_Based_Pointer_Basic (void);

  /**
   * Initialize this object using the @a initial pointer.  This
   * constructor initializes the <base_offset_> by asking the
   * <ACE_BASED_POINTER_REPOSITORY> Singleton for the base address of
   * the memory region within which it is instantiated.  Three results
   * are possible:
   *
   * 1. An <ACE_*_Memory_Pool> has stored a base address/size pair and the
   *    new based-pointer instance is located between the base address and
   *    the base address + size - 1.  In this case, the repository
   *    returns the base address.
   *
   * 2. No suitable address/size pair was found.  The repository
   *    assumes an address in the regular (not mapped) virtual address
   *    space of the process and returns 0.  In this case, the
   *    based-pointer uses its address as an offset to its base
   *    address 0.
   *
   * 3. If @a initial is 0 then set the value of <target_> to -1, which
   *    indicates a "NULL" pointer.
   */
  ACE_Based_Pointer_Basic (CONCRETE *initial);

  /// Copy constructor.
  ACE_Based_Pointer_Basic (const ACE_Based_Pointer_Basic<CONCRETE> &);

  /// Constructor for know base address. @a o is only used to
  /// resolve overload ambiguity.
  ACE_Based_Pointer_Basic (const void *base_addr, int o);

  /// Pseudo-assignment operator.
  void operator = (CONCRETE *from);

  /// Pseudo-assignment operator.
  void operator = (const ACE_Based_Pointer_Basic<CONCRETE> &);

  /// Dereference operator.
  CONCRETE operator * () const;

  /// Less than operator.
  bool operator < (const ACE_Based_Pointer_Basic<CONCRETE> &) const;

  /// Less than or equal operator.
  bool operator <= (const ACE_Based_Pointer_Basic<CONCRETE> &) const;

  /// Greater than operator.
  bool operator > (const ACE_Based_Pointer_Basic<CONCRETE> &) const;

  /// Greater than or equal operator.
  bool operator >= (const ACE_Based_Pointer_Basic<CONCRETE> &) const;

  /// Equality operator.
  bool operator == (const ACE_Based_Pointer_Basic<CONCRETE> &) const;

  /// Inequality operator.
  bool operator != (const ACE_Based_Pointer_Basic<CONCRETE> &) const;

  /// Subscript operator.
  CONCRETE operator [](int index) const;

  /// Increment operator.
  void operator+= (int index);

  /// Returns the underlying memory address of the smart pointer.
  operator CONCRETE *() const;

  /// Returns the underlying memory address of the smart pointer.
  CONCRETE *addr () const;

  /// Declare the dynamic allocation hooks.
  ACE_ALLOC_HOOK_DECLARE;

  /// Dump the state of the object.
  void dump () const;

protected:
  ptrdiff_t target_;

  /// Keep track of our offset from the base pointer.
  ptrdiff_t base_offset_;
};

/**
 * @class ACE_Based_Pointer
 *
 * @brief A smart proxy that keeps track of the relative offset of a
 * "pointer" from its base address.
 *
 * This class makes it possible to transparently use "pointers" in
 * shared memory as easily as programming with pointers to local
 * memory by overloading the C++ delegation operator ->().
 */
template <class CONCRETE>
class ACE_Based_Pointer : public ACE_Based_Pointer_Basic<CONCRETE>
{
public:
  /// Constructor.  See constructor for ACE_Based_Pointer_Basic for
  /// details.
  ACE_Based_Pointer (void);

  /// Initialize this object using the <initial> pointer.  See
  /// constructor for ACE_Based_Pointer_Basic for details.
  ACE_Based_Pointer (CONCRETE *initial);

  /// Initialize this object with known @a base_addr.  @a dummy is
  /// a dummy value used to resolve overload ambiguity and it
  /// otherwise ignored.
  ACE_Based_Pointer (const void *base_addr, int dummy);

  /// Copy constructor (not implemented yet).
  ACE_Based_Pointer (const ACE_Based_Pointer<CONCRETE> &);

  /// Assignment operator.
  void operator = (const ACE_Based_Pointer<CONCRETE> &);

  /// Pseudo-assignment operator.
  void operator = (CONCRETE *from);

  /// The C++ "delegation operator".
  CONCRETE *operator-> (void);
};

ACE_END_VERSIONED_NAMESPACE_DECL

#if defined (__ACE_INLINE__)
#include "ace/Based_Pointer_T.inl"
#endif /* __ACE_INLINE__ */

#if defined (ACE_TEMPLATES_REQUIRE_SOURCE)
#include "ace/Based_Pointer_T.cpp"
#endif /* ACE_TEMPLATES_REQUIRE_SOURCE */

#if defined (ACE_TEMPLATES_REQUIRE_PRAGMA)
#pragma implementation ("Based_Pointer_T.cpp")
#endif /* ACE_TEMPLATES_REQUIRE_PRAGMA */

#include /**/ "ace/post.h"

#endif /* ACE_BASED_POINTER_T_H */