PMDK C++ bindings  1.6.1
This is the C++ bindings documentation for PMDK's libpmemobj.
shared_mutex.hpp
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32 
38 #ifndef LIBPMEMOBJ_CPP_SHARED_MUTEX_HPP
39 #define LIBPMEMOBJ_CPP_SHARED_MUTEX_HPP
40 
41 #include <libpmemobj/thread.h>
42 #include <libpmemobj/tx_base.h>
43 
44 namespace pmem
45 {
46 
47 namespace obj
48 {
49 
59 class shared_mutex {
60 public:
62  typedef PMEMrwlock *native_handle_type;
63 
71  {
72  PMEMobjpool *pop;
73  if ((pop = pmemobj_pool_by_ptr(&plock)) == nullptr)
74  throw lock_error(
75  1, std::generic_category(),
76  "Persistent shared mutex not from persistent memory.");
77 
78  pmemobj_rwlock_zero(pop, &plock);
79  }
80 
84  ~shared_mutex() = default;
85 
98  void
99  lock()
100  {
101  PMEMobjpool *pop = pmemobj_pool_by_ptr(this);
102  if (int ret = pmemobj_rwlock_wrlock(pop, &this->plock))
103  throw lock_error(ret, std::system_category(),
104  "Failed to lock a shared mutex.");
105  }
106 
122  void
124  {
125  PMEMobjpool *pop = pmemobj_pool_by_ptr(this);
126  if (int ret = pmemobj_rwlock_rdlock(pop, &this->plock))
127  throw lock_error(
128  ret, std::system_category(),
129  "Failed to shared lock a shared mutex.");
130  }
131 
146  bool
148  {
149  PMEMobjpool *pop = pmemobj_pool_by_ptr(this);
150  int ret = pmemobj_rwlock_trywrlock(pop, &this->plock);
151 
152  if (ret == 0)
153  return true;
154  else if (ret == EBUSY)
155  return false;
156  else
157  throw lock_error(ret, std::system_category(),
158  "Failed to lock a shared mutex.");
159  }
160 
177  bool
179  {
180  PMEMobjpool *pop = pmemobj_pool_by_ptr(this);
181  int ret = pmemobj_rwlock_tryrdlock(pop, &this->plock);
182 
183  if (ret == 0)
184  return true;
185  else if (ret == EBUSY)
186  return false;
187  else
188  throw lock_error(ret, std::system_category(),
189  "Failed to lock a shared mutex.");
190  }
191 
198  void
200  {
201  PMEMobjpool *pop = pmemobj_pool_by_ptr(this);
202  int ret = pmemobj_rwlock_unlock(pop, &this->plock);
203  if (ret)
204  throw lock_error(ret, std::system_category(),
205  "Failed to unlock a shared mutex.");
206  }
207 
214  void
216  {
217  this->unlock();
218  }
219 
225  native_handle_type
226  native_handle() noexcept
227  {
228  return &this->plock;
229  }
230 
236  enum pobj_tx_param
237  lock_type() const noexcept
238  {
239  return TX_PARAM_RWLOCK;
240  }
241 
245  shared_mutex &operator=(const shared_mutex &) = delete;
246 
250  shared_mutex(const shared_mutex &) = delete;
251 
252 private:
254  PMEMrwlock plock;
255 };
256 
257 } /* namespace obj */
258 
259 } /* namespace pmem */
260 
261 #endif /* LIBPMEMOBJ_CPP_SHARED_MUTEX_HPP */
pmem::obj::shared_mutex::shared_mutex
shared_mutex()
Default constructor.
Definition: shared_mutex.hpp:70
pmem::obj::shared_mutex::lock
void lock()
Lock the mutex for exclusive access.
Definition: shared_mutex.hpp:99
pmem::obj::shared_mutex::operator=
shared_mutex & operator=(const shared_mutex &)=delete
Deleted assignment operator.
pmem::obj::shared_mutex::native_handle
native_handle_type native_handle() noexcept
Access a native handle to this shared mutex.
Definition: shared_mutex.hpp:226
pmem::obj::shared_mutex::try_lock
bool try_lock()
Try to lock the mutex for exclusive access, returns regardless if the lock succeeds.
Definition: shared_mutex.hpp:147
pmem::obj::shared_mutex::shared_mutex
shared_mutex(const shared_mutex &)=delete
Deleted copy constructor.
pmem::obj::shared_mutex::try_lock_shared
bool try_lock_shared()
Try to lock the mutex for shared access, returns regardless if the lock succeeds.
Definition: shared_mutex.hpp:178
pmem::obj::shared_mutex::unlock
void unlock()
Unlocks the mutex.
Definition: shared_mutex.hpp:199
pmem::lock_error
Custom lock error class.
Definition: pexceptions.hpp:74
pmem::obj::shared_mutex::lock_type
enum pobj_tx_param lock_type() const noexcept
The type of lock needed for the transaction API.
Definition: shared_mutex.hpp:237
pmem::obj::shared_mutex::plock
PMEMrwlock plock
A POSIX style PMEM-resident shared_mutex.
Definition: shared_mutex.hpp:254
pmem::obj::shared_mutex::lock_shared
void lock_shared()
Lock the mutex for shared access.
Definition: shared_mutex.hpp:123
pmem::obj::shared_mutex::~shared_mutex
~shared_mutex()=default
Defaulted destructor.
pmem::obj::shared_mutex::native_handle_type
PMEMrwlock * native_handle_type
Implementation defined handle to the native type.
Definition: shared_mutex.hpp:62
pmem::obj::shared_mutex
Persistent memory resident shared_mutex implementation.
Definition: shared_mutex.hpp:59
pmem::obj::shared_mutex::unlock_shared
void unlock_shared()
Unlocks the mutex.
Definition: shared_mutex.hpp:215