MPD  0.20.18
PosixMutex.hxx
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29 
30 #ifndef THREAD_POSIX_MUTEX_HXX
31 #define THREAD_POSIX_MUTEX_HXX
32 
33 #include <pthread.h>
34 
38 class PosixMutex {
39  friend class PosixCond;
40 
41  pthread_mutex_t mutex;
42 
43 public:
44 #ifdef __GLIBC__
45  /* optimized constexpr constructor for pthread implementations
46  that support it */
47  constexpr PosixMutex():mutex(PTHREAD_MUTEX_INITIALIZER) {}
48 #else
49  /* slow fallback for pthread implementations that are not
50  compatible with "constexpr" */
52  pthread_mutex_init(&mutex, nullptr);
53  }
54 
56  pthread_mutex_destroy(&mutex);
57  }
58 #endif
59 
60  PosixMutex(const PosixMutex &other) = delete;
61  PosixMutex &operator=(const PosixMutex &other) = delete;
62 
63  void lock() {
64  pthread_mutex_lock(&mutex);
65  }
66 
67  bool try_lock() {
68  return pthread_mutex_trylock(&mutex) == 0;
69  }
70 
71  void unlock() {
72  pthread_mutex_unlock(&mutex);
73  }
74 };
75 
76 #endif
Low-level wrapper for a pthread_cond_t.
Definition: PosixCond.hxx:42
Low-level wrapper for a pthread_mutex_t.
Definition: PosixMutex.hxx:38
PosixMutex & operator=(const PosixMutex &other)=delete
bool try_lock()
Definition: PosixMutex.hxx:67
void unlock()
Definition: PosixMutex.hxx:71
void lock()
Definition: PosixMutex.hxx:63