threadmm::lock_guard< Lock > Class Template Reference [Utility classes] #include <threadmm/lock_guard.hh> Collaboration diagram for threadmm::lock_guard< Lock >: [legend]List of all members. Detailed Description template<typename Lock> class threadmm::lock_guard< Lock > Lock_Guard class used to lock mutex's. Parameters: Lock  The kind of locks to use. This class is useful for writting thread-safe code. One creates a lock_guard object on the stack on entry into the critical section, passing it a mutex to lock. When the lock_guard object goes out of scope, the mutex is automatically released. This is a fairly well-known trick to use. Here's an example for a class fulfilling a Singleton pattern, were we protect the singleton creation from race conditions in the case mutliple threads call the singleton::instance() member function: #ifdef _REENTRANT #define MUTEX_TYPE threadmm::mutex #else #define MUTEX_TYPE threadmm::mutex_dummy #endif template <typename Mutex=MUTEX_TYPE> class singleton { private: static Mutex _mutex; static singleton* _instance; public: singleton() {} static singleton* instance() { if (!_instance) { threadmm::lock_guard g(_mutex); if (!_instance) _instance = new singleton; } return _instance; } }; In a single threaded application, the user can pass some dummy mutex class as the template argument, and suffer no penalties. Examples: barrier_sync.cc, and prod_cons_cond.cc. Public Types typedef Lock  lock_type Public Member Functions   lock_guard (lock_type &l, bool spin=false)   lock_guard (volatile lock_type &l, bool spin=false) virtual  ~lock_guard () void  lock (bool spin=false) void  lock (bool spin=false) volatile void  unlock () Protected Attributes lock_type &  _lock bool  _released Member Typedef Documentation template<typename Lock> typedef Lock threadmm::lock_guard< Lock >::lock_type   Type of the lock. Constructor & Destructor Documentation template<typename Lock> threadmm::lock_guard< Lock >::lock_guard (  lock_type &  l, bool  spin = false )  [inline]   Constructor. Locks the passed lock. See also lock member function. Parameters: l  The lock to use with this lock_guard. spin  see lock member function. template<typename Lock> threadmm::lock_guard< Lock >::lock_guard (  volatile lock_type &  l, bool  spin = false )  [inline]   Constructor. Locks the passed lock. See also lock member function. Parameters: l  The lock to use with this lock_guard. spin  see lock member function. template<typename Lock> virtual threadmm::lock_guard< Lock >::~lock_guard (   )  [inline, virtual]   Destructor. Unlocks the stored lock. Member Function Documentation template<typename Lock> void threadmm::lock_guard< Lock >::lock (  bool  spin = false  )  volatile   Lock the lock passed to the constructor. Parameters: spin  If true, the guard will loop indefently until it gets a lock (via Lock::try_lock member function). Otherwise, it will attempt a normal lock. template<typename Lock> void threadmm::lock_guard< Lock >::lock (  bool  spin = false  )    Lock the lock passed to the constructor. Parameters: spin  If true, the guard will loop indefently until it gets a lock (via Lock::try_lock member function). Otherwise, it will attempt a normal lock. template<typename Lock> void threadmm::lock_guard< Lock >::unlock (   )  [inline]   Unlock the lock passed to the constructor. Member Data Documentation template<typename Lock> lock_type& threadmm::lock_guard< Lock >::_lock [protected]   The lock to use. template<typename Lock> bool threadmm::lock_guard< Lock >::_released [protected]   Flag. True if lock was released (by unlock member function) before the deconstructor was reached (scope ended). The documentation for this class was generated from the following file: lock_guard.hh