PMDK C++ bindings  1.7.1
This is the C++ bindings documentation for PMDK's libpmemobj.
mutex.hpp
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32 
38 #ifndef LIBPMEMOBJ_CPP_MUTEX_HPP
39 #define LIBPMEMOBJ_CPP_MUTEX_HPP
40 
42 #include <libpmemobj/thread.h>
43 #include <libpmemobj/tx_base.h>
44 
45 namespace pmem
46 {
47 
48 namespace obj
49 {
50 
60 class mutex {
61 public:
63  typedef PMEMmutex *native_handle_type;
64 
71  {
72  PMEMobjpool *pop;
73  if ((pop = pmemobj_pool_by_ptr(&plock)) == nullptr)
74  throw lock_error(
75  1, std::generic_category(),
76  "Persistent mutex not from persistent memory.");
77 
78  pmemobj_mutex_zero(pop, &plock);
79  }
80 
84  ~mutex() = default;
85 
97  void
98  lock()
99  {
100  PMEMobjpool *pop = pmemobj_pool_by_ptr(this);
101  if (int ret = pmemobj_mutex_lock(pop, &this->plock))
102  throw lock_error(ret, std::system_category(),
103  "Failed to lock a mutex.");
104  }
105 
120  bool
122  {
123  PMEMobjpool *pop = pmemobj_pool_by_ptr(this);
124  int ret = pmemobj_mutex_trylock(pop, &this->plock);
125 
126  if (ret == 0)
127  return true;
128  else if (ret == EBUSY)
129  return false;
130  else
131  throw lock_error(ret, std::system_category(),
132  "Failed to lock a mutex.");
133  }
134 
142  void
144  {
145  PMEMobjpool *pop = pmemobj_pool_by_ptr(this);
146  int ret = pmemobj_mutex_unlock(pop, &this->plock);
147  if (ret)
148  throw lock_error(ret, std::system_category(),
149  "Failed to unlock a mutex.");
150  }
151 
158  native_handle() noexcept
159  {
160  return &this->plock;
161  }
162 
168  enum pobj_tx_param
169  lock_type() const noexcept
170  {
171  return TX_PARAM_MUTEX;
172  }
173 
177  mutex &operator=(const mutex &) = delete;
178 
182  mutex(const mutex &) = delete;
183 
184 private:
186  PMEMmutex plock;
187 };
188 
189 } /* namespace obj */
190 
191 } /* namespace pmem */
192 
193 #endif /* LIBPMEMOBJ_CPP_MUTEX_HPP */
PMEMmutex * native_handle_type
Implementation defined handle to the native type.
Definition: mutex.hpp:63
mutex()
Default constructor.
Definition: mutex.hpp:70
enum pobj_tx_param lock_type() const noexcept
The type of lock needed for the transaction API.
Definition: mutex.hpp:169
~mutex()=default
Defaulted destructor.
native_handle_type native_handle() noexcept
Access a native handle to this condition variable.
Definition: mutex.hpp:158
Custom exceptions.
PMEMmutex plock
A POSIX style PMEM-resident mutex.
Definition: mutex.hpp:186
Persistent memory resident mutex implementation.
Definition: mutex.hpp:60
void lock()
Locks the mutex, blocks if already locked.
Definition: mutex.hpp:98
mutex & operator=(const mutex &)=delete
Deleted assignment operator.
Custom lock error class.
Definition: pexceptions.hpp:74
bool try_lock()
Tries to lock the mutex, returns regardless if the lock succeeds.
Definition: mutex.hpp:121
void unlock()
Unlocks a previously locked mutex.
Definition: mutex.hpp:143