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+ //////////////////////////////////////////////////////////////////////////////
+//
+// (C) Copyright Ion Gaztanaga 2005-2011. 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
+
+#if (defined _MSC_VER) && (_MSC_VER >= 1200)
+# 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>
+#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
+{
+ /// @cond
+
+ //Non-copyable
+ named_semaphore();
+ named_semaphore(const named_semaphore &);
+ named_semaphore &operator=(const named_semaphore &);
+ /// @endcond
+
+ 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);
+
+ /// @cond
+ 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;
+ #else
+ typedef ipcdetail::shm_named_semaphore impl_t;
+ #endif
+ impl_t m_sem;
+ /// @endcond
+};
+
+/// @cond
+
+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)
+{
+ if(abs_time == boost::posix_time::pos_infin){
+ this->wait();
+ return true;
+ }
+ return m_sem.timed_wait(abs_time);
+}
+
+inline bool named_semaphore::remove(const char *name)
+{ return impl_t::remove(name); }
+
+/// @endcond
+
+} //namespace interprocess {
+} //namespace boost {
+
+
+#include <boost/interprocess/detail/config_end.hpp>
+
+#endif //BOOST_INTERPROCESS_NAMED_SEMAPHORE_HPP