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Editing: named_semaphore.hpp
////////////////////////////////////////////////////////////////////////////// // // (C) Copyright Ion Gaztanaga 2005-2012. Distributed under the Boost // Software License, Version 1.0. (See accompanying file // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) // // See http://www.boost.org/libs/interprocess for documentation. // ////////////////////////////////////////////////////////////////////////////// #ifndef BOOST_INTERPROCESS_NAMED_SEMAPHORE_HPP #define BOOST_INTERPROCESS_NAMED_SEMAPHORE_HPP #ifndef BOOST_CONFIG_HPP # include <boost/config.hpp> #endif # #if defined(BOOST_HAS_PRAGMA_ONCE) # pragma once #endif #include <boost/interprocess/detail/config_begin.hpp> #include <boost/interprocess/detail/workaround.hpp> #include <boost/interprocess/creation_tags.hpp> #include <boost/interprocess/exceptions.hpp> #include <boost/interprocess/permissions.hpp> #include <boost/interprocess/detail/interprocess_tester.hpp> #include <boost/interprocess/detail/posix_time_types_wrk.hpp> #if defined(BOOST_INTERPROCESS_NAMED_SEMAPHORE_USES_POSIX_SEMAPHORES) #include <boost/interprocess/sync/posix/named_semaphore.hpp> //Experimental... #elif !defined(BOOST_INTERPROCESS_FORCE_GENERIC_EMULATION) && defined (BOOST_INTERPROCESS_WINDOWS) #include <boost/interprocess/sync/windows/named_semaphore.hpp> #define BOOST_INTERPROCESS_USE_WINDOWS #else #include <boost/interprocess/sync/shm/named_semaphore.hpp> #endif //!\file //!Describes a named semaphore class for inter-process synchronization namespace boost { namespace interprocess { //!A semaphore with a global name, so it can be found from different //!processes. Allows several resource sharing patterns and efficient //!acknowledgment mechanisms. class named_semaphore { #if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED) //Non-copyable named_semaphore(); named_semaphore(const named_semaphore &); named_semaphore &operator=(const named_semaphore &); #endif //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED public: //!Creates a global semaphore with a name, and an initial count. //!If the semaphore can't be created throws interprocess_exception named_semaphore(create_only_t, const char *name, unsigned int initialCount, const permissions &perm = permissions()); //!Opens or creates a global semaphore with a name, and an initial count. //!If the semaphore is created, this call is equivalent to //!named_semaphore(create_only_t, ...) //!If the semaphore is already created, this call is equivalent to //!named_semaphore(open_only_t, ... ) //!and initialCount is ignored. named_semaphore(open_or_create_t, const char *name, unsigned int initialCount, const permissions &perm = permissions()); //!Opens a global semaphore with a name if that semaphore is previously. //!created. If it is not previously created this function throws //!interprocess_exception. named_semaphore(open_only_t, const char *name); //!Destroys *this and indicates that the calling process is finished using //!the resource. The destructor function will deallocate //!any system resources allocated by the system for use by this process for //!this resource. The resource can still be opened again calling //!the open constructor overload. To erase the resource from the system //!use remove(). ~named_semaphore(); //!Increments the semaphore count. If there are processes/threads blocked waiting //!for the semaphore, then one of these processes will return successfully from //!its wait function. If there is an error an interprocess_exception exception is thrown. void post(); //!Decrements the semaphore. If the semaphore value is not greater than zero, //!then the calling process/thread blocks until it can decrement the counter. //!If there is an error an interprocess_exception exception is thrown. void wait(); //!Decrements the semaphore if the semaphore's value is greater than zero //!and returns true. If the value is not greater than zero returns false. //!If there is an error an interprocess_exception exception is thrown. bool try_wait(); //!Decrements the semaphore if the semaphore's value is greater //!than zero and returns true. Otherwise, waits for the semaphore //!to the posted or the timeout expires. If the timeout expires, the //!function returns false. If the semaphore is posted the function //!returns true. If there is an error throws sem_exception bool timed_wait(const boost::posix_time::ptime &abs_time); //!Erases a named semaphore from the system. //!Returns false on error. Never throws. static bool remove(const char *name); #if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED) private: friend class ipcdetail::interprocess_tester; void dont_close_on_destruction(); #if defined(BOOST_INTERPROCESS_NAMED_SEMAPHORE_USES_POSIX_SEMAPHORES) typedef ipcdetail::posix_named_semaphore impl_t; #elif defined(BOOST_INTERPROCESS_USE_WINDOWS) #undef BOOST_INTERPROCESS_USE_WINDOWS typedef ipcdetail::windows_named_semaphore impl_t; #else typedef ipcdetail::shm_named_semaphore impl_t; #endif impl_t m_sem; #endif //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED }; #if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED) inline named_semaphore::named_semaphore (create_only_t, const char *name, unsigned int initialCount, const permissions &perm) : m_sem(create_only, name, initialCount, perm) {} inline named_semaphore::named_semaphore (open_or_create_t, const char *name, unsigned int initialCount, const permissions &perm) : m_sem(open_or_create, name, initialCount, perm) {} inline named_semaphore::named_semaphore(open_only_t, const char *name) : m_sem(open_only, name) {} inline named_semaphore::~named_semaphore() {} inline void named_semaphore::dont_close_on_destruction() { ipcdetail::interprocess_tester::dont_close_on_destruction(m_sem); } inline void named_semaphore::wait() { m_sem.wait(); } inline void named_semaphore::post() { m_sem.post(); } inline bool named_semaphore::try_wait() { return m_sem.try_wait(); } inline bool named_semaphore::timed_wait(const boost::posix_time::ptime &abs_time) { return m_sem.timed_wait(abs_time); } inline bool named_semaphore::remove(const char *name) { return impl_t::remove(name); } #endif //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED } //namespace interprocess { } //namespace boost { #include <boost/interprocess/detail/config_end.hpp> #endif //BOOST_INTERPROCESS_NAMED_SEMAPHORE_HPP
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