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
|
/*
* Copyright © 2016 Canonical Ltd.
*
* This program is free software: you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License version 2 or 3,
* as published by the Free Software Foundation.
*
* 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 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/>.
*
* Authored by: Christopher James Halse Rogers <christopher.halse.rogers@canonical.com>
*/
#ifndef MIR_POSIX_RW_MUTEX_H_
#define MIR_POSIX_RW_MUTEX_H_
#include <pthread.h>
namespace mir
{
/**
* Implementation of the Mutex and SharedMutex C++14 concepts via POSIX pthread rwlock
*
* The advantages of using this over std::shared_timed_mutex are:
* a) The type of rwlock can be selected (as per pthread_rwlock_attr_setkind_np)
* b) As per POSIX, read locks are recursive rather than undefined behaviour
*/
class PosixRWMutex
{
public:
enum class Type
{
Default,
PreferReader,
PreferWriterNonRecursive
};
PosixRWMutex();
PosixRWMutex(Type type);
~PosixRWMutex();
PosixRWMutex(PosixRWMutex const&) = delete;
PosixRWMutex& operator=(PosixRWMutex const&) = delete;
/*
* SharedMutex concept implementation
*/
void lock_shared();
bool try_lock_shared();
void unlock_shared();
/*
* Mutex concept implementation
*/
void lock();
bool try_lock();
void unlock();
private:
pthread_rwlock_t mutex;
};
}
#endif //MIR_POSIX_RW_MUTEX_H_
|