blob: e990ded4149606a138110a861fe3a66c513cd462 (
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
|
/*
* Semaphore
* (C) 2013 Joel Low
*
* Botan is released under the Simplified BSD License (see license.txt)
*/
#include <botan/internal/semaphore.h>
#if defined(BOTAN_TARGET_OS_HAS_THREADS)
// Based on code by Pierre Gaston (http://p9as.blogspot.com/2012/06/c11-semaphores.html)
namespace Botan {
void Semaphore::release(size_t n)
{
for(size_t i = 0; i != n; ++i)
{
lock_guard_type<mutex_type> lock(m_mutex);
if(m_value++ < 0)
{
++m_wakeups;
m_cond.notify_one();
}
}
}
void Semaphore::acquire()
{
std::unique_lock<mutex_type> lock(m_mutex);
if(m_value-- <= 0)
{
m_cond.wait(lock, [this] { return m_wakeups > 0; });
--m_wakeups;
}
}
}
#endif
|