-
Notifications
You must be signed in to change notification settings - Fork 0
/
shareddata.h
97 lines (84 loc) · 2.21 KB
/
shareddata.h
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
/*
* Copyright (C) 2007 Simon Perreault
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef SHAREDDATA_H
#define SHAREDDATA_H
#include <algorithm>
/**
* \warning This class isn't thread-safe! In particular, we should use atomic
* operations when incrementing or decrementing the reference count. See Boost's
* shared_ptr for an alternative.
*/
template< typename T >
class SharedData
{
public:
SharedData( T* data = 0 );
SharedData( const SharedData<T>& sharedData );
~SharedData();
void swap( SharedData<T>& sharedData );
SharedData<T>& operator= ( SharedData<T> sharedData );
T& operator[] ( int i ) const;
private:
T* data_;
int* refcount_;
};
template< typename T >
SharedData<T>::SharedData( T* data )
: data_(data)
{
try {
refcount_ = new int(1);
}
catch (...) {
delete[] data_;
throw;
}
}
template< typename T >
SharedData<T>::SharedData( const SharedData<T>& sharedData )
: data_( sharedData.data_ )
, refcount_( sharedData.refcount_ )
{
++*refcount_;
}
template< typename T >
SharedData<T>::~SharedData()
{
if ( --*refcount_ == 0 ) {
delete[] data_;
delete refcount_;
}
}
template< typename T >
void SharedData<T>::swap( SharedData<T>& sharedData )
{
std::swap( sharedData.data_, data_ );
std::swap( sharedData.refcount_, refcount_ );
}
template< typename T >
SharedData<T>& SharedData<T>::operator= ( SharedData<T> sharedData )
{
swap(sharedData);
return *this;
}
template< typename T >
T& SharedData<T>::operator[] ( int i ) const
{
assert(data_);
return data_[i];
}
#endif