summaryrefslogtreecommitdiffstats
path: root/libdimensionxx/dimensionxx/array.hpp
blob: 735e17a8e8ecb6bcad281b2bd2e91f5a752a377e (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
/*************************************************************************
 * Copyright (C) 2008 Tavian Barnes <tavianator@gmail.com>               *
 *                                                                       *
 * This file is part of The Dimension Library.                           *
 *                                                                       *
 * The Dimension Library is free software; you can redistribute it and/  *
 * or modify it under the terms of the GNU Lesser General Public License *
 * as published by the Free Software Foundation; either version 3 of the *
 * License, or (at your option) any later version.                       *
 *                                                                       *
 * The Dimension Library is distributed in the hope that it will be      *
 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty   *
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU  *
 * Lesser General Public License for more details.                       *
 *                                                                       *
 * You should have received a copy of the GNU Lesser General Public      *
 * License along with this program.  If not, see                         *
 * <http://www.gnu.org/licenses/>.                                       *
 *************************************************************************/

// dmnsn_array* wrapper.

#ifndef DIMENSIONXX_ARRAY_HPP
#define DIMENSIONXX_ARRAY_HPP

#include <tr1/memory> // For tr1::shared_ptr
#include <cstdlib>    // For size_t

namespace Dimension
{
  // RAII scoped read-lock
  class Array_Read_Lock
  {
  public:
    explicit Array_Read_Lock(const dmnsn_array* array)
      : m_array(new const dmnsn_array*(array)) { dmnsn_array_rdlock(*m_array); }
    // Array_Read_Lock(const Array_Read_Lock& lock);
    ~Array_Read_Lock()
    { if (m_array.unique()) { dmnsn_array_unlock(*m_array); } }

  private:
    // Copy assignment prohibited
    Array_Read_Lock& operator=(const Array_Read_Lock&);

    std::tr1::shared_ptr<const dmnsn_array*> m_array;
  };

  // RAII scoped write-lock
  class Array_Write_Lock
  {
  public:
    explicit Array_Write_Lock(dmnsn_array* array)
      : m_array(new dmnsn_array*(array)) { dmnsn_array_wrlock(*m_array); }
    // Array_Write_Lock(const Array_Write_Lock& lock);
    ~Array_Write_Lock()
    { if (m_array.unique()) { dmnsn_array_unlock(*m_array); } }

  private:
    // Copy assignment prohibited
    Array_Write_Lock& operator=(const Array_Write_Lock&);

    std::tr1::shared_ptr<dmnsn_array*> m_array;
  };

  // Array template class, wraps a dmnsn_array*.  Copying is possible, but
  // copies refer to the same object, which is reference counted.  T must be
  // a POD type.
  template <typename T>
  class Array
  {
  public:
    Array();
    explicit Array(dmnsn_array* array);
    // Array(const Array& a);
    ~Array()
    { if (m_array && m_array.unique()) { dmnsn_delete_array(dmnsn()); } }

    // Array& operator=(const Array& a);

    inline T at(std::size_t i) const;
    void set(std::size_t i, T object) { dmnsn_array_set(dmnsn(), i, &object); }

    std::size_t size() const { return dmnsn_array_size(dmnsn()); }
    void resize(std::size_t size) { dmnsn_array_resize(dmnsn(), size); }

    // For manual locking

    Array_Read_Lock read_lock() const { return Array_Read_Lock(dmnsn()); }
    Array_Write_Lock write_lock() { return Array_Write_Lock(dmnsn()); }

    T& operator[](std::size_t i)
    { return *reinterpret_cast<T*>(dmnsn_array_at(dmnsn(), i)); }
    const T& operator[](std::size_t i) const
    { return *reinterpret_cast<const T*>(dmnsn_array_at(dmnsn(), i)); }
    std::size_t size_unlocked() const
    { return dmnsn_array_size_unlocked(dmnsn()); }
    void resize_unlocked(std::size_t size)
    { dmnsn_array_resize_unlocked(dmnsn(), size); }

    // Access the wrapped C object.
    dmnsn_array*       dmnsn();
    const dmnsn_array* dmnsn() const;

    // Release ownership of the dmnsn_array*, needed for returning a
    // dmnsn_array* from a function.
    dmnsn_array* release();

  private:
    std::tr1::shared_ptr<dmnsn_array*> m_array;
  };

  // A constraint enforcing that T is a POD type by making it part of a union.
  // Taking the address of this function will cause a compile-time failure if
  // T is not a POD type.
  template <typename T>
  void
  POD_constraint()
  {
    union
    {
      T t;
    } constraint;
    static_cast<void>(constraint); // Silence unused variable warning
  }

  template <typename T>
  Array<T>::Array()
    : m_array(new dmnsn_array*(dmnsn_new_array(sizeof(T))))
  {
    void (*constraint)() = &POD_constraint<T>;
    static_cast<void>(constraint); // Silence unused variable warning
  }

  template <typename T>
  Array<T>::Array(dmnsn_array* array)
    : m_array(new dmnsn_array*(array))
  {
    void (*constraint)() = &POD_constraint<T>;
    static_cast<void>(constraint); // Silence unused variable warning
  }

  template <typename T>
  inline T
  Array<T>::at(std::size_t i) const
  {
    T ret;
    dmnsn_array_get(dmnsn(), i, &ret);
    return ret;
  }

  // Access the underlying dmnsn_array*

  template <typename T>
  dmnsn_array*
  Array<T>::dmnsn()
  {
    if (!m_array) {
      throw Dimension_Error("Attempting to access released array.");
    }

    return *m_array;
  }

  template <typename T>
  const dmnsn_array*
  Array<T>::dmnsn() const
  {
    if (!m_array) {
      throw Dimension_Error("Attempting to access released array.");
    }

    return *m_array;
  }

  // Release the dmnsn_array*, if we are the only Array holding it
  template <typename T>
  dmnsn_array*
  Array<T>::release()
  {
    dmnsn_array* array = dmnsn();

    if (!m_array.unique()) {
      throw Dimension_Error("Attempting to release non-unique array.");
    } else {
      m_array.reset();
      return array;
    }
  }
}

#endif /* DIMENSIONXX_ARRAY_HPP */