blocxx
AtomicOps.cpp
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32
33
38#include "blocxx/BLOCXX_config.h"
39#include "blocxx/AtomicOps.hpp"
40
41#if defined(BLOCXX_USE_PTHREAD_SPIN_LOCK_ATOMIC_OPS)
42
43namespace BLOCXX_NAMESPACE
44{
45
47 : val(0)
48{
49 pthread_spin_init(&spinlock, 0);
50}
51Atomic_t::Atomic_t(int i)
52 : val(i)
53{
54 pthread_spin_init(&spinlock, 0);
55}
57{
58 pthread_spin_lock(&v.spinlock);
59 ++v.val;
60 pthread_spin_unlock(&v.spinlock);
61}
63{
64 pthread_spin_lock(&v.spinlock);
65 --v.val;
66 bool b = ((v.val == 0) ? true : false) ;
67 pthread_spin_unlock(&v.spinlock);
68 return b;
69}
70int AtomicGet(Atomic_t const &v)
71{
72 return v.val;
73}
75{
76 pthread_spin_lock(&v.spinlock);
77 --v.val;
78 pthread_spin_unlock(&v.spinlock);
79}
80
81} // end namespace BLOCXX_NAMESPACE
82
83#elif defined(BLOCXX_USE_BLOCXX_DEFAULT_ATOMIC_OPS)
84#include "blocxx/Mutex.hpp"
85#include "blocxx/MutexLock.hpp"
86#include "blocxx/ThreadOnce.hpp"
87
88namespace BLOCXX_NAMESPACE
89{
90
91// this needs to be a pointer because of static initialization order conflicts.
92// It shouldn't ever be deleted b/c it may be referenced by a destructor of a
93// static variable that is being deleted.
94static Mutex* guard = 0;
95static OnceFlag g_once = BLOCXX_ONCE_INIT;
96static void initGuard()
97{
98 guard = new Mutex();
99}
100void AtomicInc(Atomic_t &v)
101{
102 callOnce(g_once, initGuard);
103 MutexLock lock(*guard);
104 ++v.val;
105}
106bool AtomicDecAndTest(Atomic_t &v)
107{
108 callOnce(g_once, initGuard);
109 MutexLock lock(*guard);
110 return --v.val == 0;
111}
112int AtomicGet(Atomic_t const &v)
113{
114 callOnce(g_once, initGuard);
115 MutexLock lock(*guard);
116 return v.val;
117}
118void AtomicDec(Atomic_t &v)
119{
120 callOnce(g_once, initGuard);
121 MutexLock lock(*guard);
122 --v.val;
123}
124
125} // end namespace BLOCXX_NAMESPACE
126
127#endif
128
129
Taken from RFC 1321.
void BLOCXX_COMMON_API callOnce(OnceFlag &flag, FuncT F)
The first time callOnce is called with a given onceFlag argument, it calls func with no argument and ...
bool AtomicDecAndTest(Atomic_t &v)
Definition AtomicOps.cpp:62
void AtomicInc(Atomic_t &v)
Definition AtomicOps.cpp:56
void AtomicDec(Atomic_t &v)
Definition AtomicOps.cpp:74
int AtomicGet(Atomic_t const &v)
Definition AtomicOps.cpp:70