blob: 57ba560b5ad9ebbc6875c4baedcdebe3ba9734e8 (
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
|
/*! \file
* \brief The locking_ptr is smart pointer with a scoped locking mechanism.
*
* The class is a wrapper for a volatile pointer. It enables synchronized access to the
* internal pointer by locking the passed mutex.
* locking_ptr is based on Andrei Alexandrescu's LockingPtr. For more information
* see article "volatile - Multithreaded Programmer's Best Friend" by A. Alexandrescu.
*
*
* Copyright (c) 2005-2007 Philipp Henkel
*
* Use, modification, and distribution are subject to the
* Boost Software License, Version 1.0. (See accompanying file
* LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
*
* http://threadpool.sourceforge.net
*
*/
#ifndef THREADPOOL_DETAIL_LOCKING_PTR_HPP_INCLUDED
#define THREADPOOL_DETAIL_LOCKING_PTR_HPP_INCLUDED
#include <boost/utility.hpp>
#include <boost/thread/mutex.hpp>
namespace boost { namespace threadpool { namespace detail
{
/*! \brief Smart pointer with a scoped locking mechanism.
*
* This class is a wrapper for a volatile pointer. It enables synchronized access to the
* internal pointer by locking the passed mutex.
*/
template <typename T, typename Mutex>
class locking_ptr
: private noncopyable
{
T* m_obj; //!< The instance pointer.
Mutex & m_mutex; //!< Mutex is used for scoped locking.
public:
/// Constructor.
locking_ptr(volatile T& obj, const volatile Mutex& mtx)
: m_obj(const_cast<T*>(&obj))
, m_mutex(*const_cast<Mutex*>(&mtx))
{
// Lock mutex
m_mutex.lock();
}
/// Destructor.
~locking_ptr()
{
// Unlock mutex
m_mutex.unlock();
}
/*! Returns a reference to the stored instance.
* \return The instance's reference.
*/
T& operator*() const
{
return *m_obj;
}
/*! Returns a pointer to the stored instance.
* \return The instance's pointer.
*/
T* operator->() const
{
return m_obj;
}
};
} } } // namespace boost::threadpool::detail
#endif // THREADPOOL_DETAIL_LOCKING_PTR_HPP_INCLUDED
|