semaphore.hpp

新版本TR1的stl

    {
        WINSTL_ASSERT(NULL != m_sem);

        if(!::ReleaseSemaphore(m_sem, 1, NULL))
        {
#ifdef STLSOFT_CF_EXCEPTION_SUPPORT
            STLSOFT_THROW_X(synchronisation_exception("semaphore release failed", ::GetLastError()));
#endif /* STLSOFT_CF_EXCEPTION_SUPPORT */
        }
    }
    /// Releases a number of aquired "locks" on the semaphore,
    ///  increasing the semaphore's counter by the given value.
    ///
    /// \param numLocksToRelease The number by which to increment the
    ///  semaphore's counter. If this is greater than the available
    ///  value, the function fails. (It will throw an exception, if
    ///  exception handling is enabled, or return -1 otherwise.)
    ///
    /// \return Returns the value of the semaphore's counter prior to the
    ///  change effected by the call.
    /// \retval -1 Indicates call failure (only if exception handling is not
    ///  enabled).
    ws_long_t unlock(count_type numLocksToRelease)
    {
        WINSTL_ASSERT(NULL != m_sem);
        WINSTL_ASSERT(numLocksToRelease > 0);
        WINSTL_ASSERT(static_cast<LONG>(numLocksToRelease) > 0);

        LONG    previousCount   =   0;

        if(!::ReleaseSemaphore(m_sem, static_cast<LONG>(numLocksToRelease), &previousCount))
        {
#ifdef STLSOFT_CF_EXCEPTION_SUPPORT
            STLSOFT_THROW_X(synchronisation_exception("semaphore release failed", ::GetLastError()));
#else /* ? STLSOFT_CF_EXCEPTION_SUPPORT */
            return -1;
#endif /* STLSOFT_CF_EXCEPTION_SUPPORT */
        }

        return static_cast<ws_long_t>(previousCount);
    }
/// @}

/// \name Accessors
/// @{
public:
    /// The underlying kernel object handle
    synch_handle_type handle()
    {
        return m_sem;
    }
    /// The underlying kernel object handle
    synch_handle_type get()
    {
        return m_sem;
    }
/// @}

// Implementation
private:
    static synch_handle_type create_semaphore_(LPSECURITY_ATTRIBUTES psa, count_type initialCount, count_type maxCount, ws_char_a_t const* name)
    {
        WINSTL_MESSAGE_ASSERT("Maximum semaphore count must be > 0", maxCount > 0);
        WINSTL_ASSERT(initialCount <= maxCount);

        synch_handle_type sem  =   ::CreateSemaphoreA(psa, static_cast<LONG>(initialCount), static_cast<LONG>(maxCount), name);

        if(NULL == sem)
        {
#ifdef STLSOFT_CF_EXCEPTION_SUPPORT
            STLSOFT_THROW_X(synchronisation_exception("Failed to create kernel semaphore object", ::GetLastError()));
#endif /* STLSOFT_CF_EXCEPTION_SUPPORT */
        }

        return sem;
    }
    static synch_handle_type create_semaphore_(LPSECURITY_ATTRIBUTES psa, count_type initialCount, count_type maxCount, ws_char_w_t const* name)
    {
        synch_handle_type sem  =   ::CreateSemaphoreW(psa, static_cast<LONG>(initialCount), static_cast<LONG>(maxCount), name);

        if(NULL == sem)
        {
#ifdef STLSOFT_CF_EXCEPTION_SUPPORT
            STLSOFT_THROW_X(synchronisation_exception("Failed to create kernel semaphore object", ::GetLastError()));
#endif /* STLSOFT_CF_EXCEPTION_SUPPORT */
        }

        return sem;
    }

// Members
private:
    synch_handle_type   m_sem;          // The underlying semaphore object
    const count_type    m_maxCount;     // Record of the maximum counter value
    const bool_type     m_bOwnHandle;   // Does the instance own the handle?

// Not to be implemented
private:
    semaphore(class_type const& rhs);
    semaphore& operator =(class_type const& rhs);
};

/* /////////////////////////////////////////////////////////////////////////
 * Shims
 */

/** Overload of the form of the winstl::get_synch_handle() shim for
 *    the winstl::semaphore type.
 *
 * \param sem The winstl::semaphore instance
 *
 * \retval The synchronisation handle of \c sem
 */
inline HANDLE get_synch_handle(semaphore &sem)
{
    return sem.get();
}

/** Overload of the form of the winstl::get_kernel_handle() shim for
 *    the winstl::semaphore type.
 *
 * \ingroup group__library__shims__kernel_handle_attribute
 *
 * \param sem The winstl::semaphore instance
 *
 * \retval The synchronisation handle of \c sem
 */
inline HANDLE get_kernel_handle(semaphore &sem)
{
    return sem.get();
}


#ifndef _WINSTL_NO_NAMESPACE
# if defined(_STLSOFT_NO_NAMESPACE) || \
     defined(STLSOFT_DOCUMENTATION_SKIP_SECTION)
} // namespace winstl
# else
} // namespace winstl_project
# endif /* _STLSOFT_NO_NAMESPACE */
#endif /* !_WINSTL_NO_NAMESPACE */

/** This \ref group__concept__shims "control shim" aquires a lock on the given semaphore
 *
 * \ingroup group__concept__shim__synchronisation_control
 *
 * \param sem The semaphore on which to aquire the lock.
 */
inline void lock_instance(winstl_ns_qual(semaphore) &sem)
{
    sem.lock();
}

/** This \ref group__concept__shims "control shim" releases a lock on the given semaphore
 *
 * \ingroup group__concept__shim__synchronisation_control
 *
 * \param sem The semaphore on which to release the lock
 */
inline void unlock_instance(winstl_ns_qual(semaphore) &sem)
{
    sem.unlock();
}

#ifndef _WINSTL_NO_NAMESPACE
# if defined(_STLSOFT_NO_NAMESPACE) || \
     defined(STLSOFT_DOCUMENTATION_SKIP_SECTION)
namespace winstl {
# else
namespace winstl_project {
#  if defined(STLSOFT_COMPILER_IS_BORLAND)
using ::stlsoft::lock_instance;
using ::stlsoft::unlock_instance;
#  endif /* compiler */
# endif /* _STLSOFT_NO_NAMESPACE */
#endif /* !_WINSTL_NO_NAMESPACE */

/* /////////////////////////////////////////////////////////////////////////
 * lock_traits
 */

// class lock_traits
/** Traits for the semaphore class
 *
 * \ingroup group__library__synch
 */
struct semaphore_lock_traits
{
public:
    /// The lockable type
    typedef semaphore                lock_type;
    typedef semaphore_lock_traits    class_type;

// Operations
public:
    /// Lock the given semaphore instance
    static void lock(semaphore &c)
    {
        lock_instance(c);
    }

    /// Unlock the given semaphore instance
    static void unlock(semaphore &c)
    {
        unlock_instance(c);
    }
};

////////////////////////////////////////////////////////////////////////////
// Unit-testing

#ifdef STLSOFT_UNITTEST
# include "./unittest/semaphore_unittest_.h"
#endif /* STLSOFT_UNITTEST */

/* ////////////////////////////////////////////////////////////////////// */

#ifndef _WINSTL_NO_NAMESPACE
# if defined(_STLSOFT_NO_NAMESPACE) || \
     defined(STLSOFT_DOCUMENTATION_SKIP_SECTION)
} // namespace winstl
# else
} // namespace winstl_project
} // namespace stlsoft
# endif /* _STLSOFT_NO_NAMESPACE */
#endif /* !_WINSTL_NO_NAMESPACE */

/* ////////////////////////////////////////////////////////////////////// */

#endif /* !WINSTL_INCL_WINSTL_SYNCH_HPP_SEMAPHORE */

/* ////////////////////////////////////////////////////////////////////// */