---

winstl_process_mutex.h

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/* 
 * File:        winstl_process_mutex.h
 *
 * Purpose:     Inter-process mutext, based on Windows MUTEX.
 *
 * Date:        15th May 2002
 * Updated:     11th September 2004
 *
 * Home:        http://stlsoft.org/
 *
 * Copyright (c) 2002-2004, Matthew Wilson and Synesis Software
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * - Redistributions of source code must retain the above copyright notice, this
 *   list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright notice,
 *   this list of conditions and the following disclaimer in the documentation
 *   and/or other materials provided with the distribution.
 * - Neither the name(s) of Matthew Wilson and Synesis Software nor the names of
 *   any contributors may be used to endorse or promote products derived from
 *   this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 * 



#ifndef WINSTL_INCL_H_WINSTL_PROCESS_MUTEX
#define WINSTL_INCL_H_WINSTL_PROCESS_MUTEX

#ifndef __STLSOFT_DOCUMENTATION_SKIP_SECTION
# define WINSTL_VER_H_WINSTL_PROCESS_MUTEX_MAJOR        2
# define WINSTL_VER_H_WINSTL_PROCESS_MUTEX_MINOR        0
# define WINSTL_VER_H_WINSTL_PROCESS_MUTEX_REVISION     1
# define WINSTL_VER_H_WINSTL_PROCESS_MUTEX_EDIT         23
#endif /* !__STLSOFT_DOCUMENTATION_SKIP_SECTION */

/* 
 * Includes
 */

#ifndef WINSTL_INCL_H_WINSTL
# include "winstl.h"    // Include the WinSTL root header
#endif /* !WINSTL_INCL_H_WINSTL */

/* 
 * Namespace
 */

#ifndef _WINSTL_NO_NAMESPACE
# if defined(_STLSOFT_NO_NAMESPACE) || \
     defined(__STLSOFT_DOCUMENTATION_SKIP_SECTION)
/* There is no stlsoft namespace, so must define ::winstl */
namespace winstl
{
# else
/* Define stlsoft::winstl_project */

namespace stlsoft
{

namespace winstl_project
{

# endif /* _STLSOFT_NO_NAMESPACE */
#endif /* !_WINSTL_NO_NAMESPACE */

/* 
 * Classes
 */

#ifdef __SYNSOFT_DBS_COMPILER_SUPPORTS_PRAGMA_MESSAGE
# pragma message(_sscomp_fileline_message("This needs to be parameterised with a winstl::system_resource_policy, which would control whether to throw if MX create fails"))
#endif /* __SYNSOFT_DBS_COMPILER_SUPPORTS_PRAGMA_MESSAGE */

// class process_mutex
class process_mutex
{
public:
    typedef process_mutex   class_type;

public:
    process_mutex() winstl_throw_0()
        : m_mx(create_mutex_(NULL, false, static_cast<ws_char_a_t const *>(0), m_bCreated))
        , m_bAbandoned(false)
    {}
    ss_explicit_k process_mutex(ws_char_a_t const *name) winstl_throw_0()
        : m_mx(create_mutex_(NULL, false, name, m_bCreated))
        , m_bAbandoned(false)
    {}
    ss_explicit_k process_mutex(ws_char_w_t const *name) winstl_throw_0()
        : m_mx(create_mutex_(NULL, false, name, m_bCreated))
        , m_bAbandoned(false)
    {}
    ss_explicit_k process_mutex(ws_bool_t bInitialOwer) winstl_throw_0()
        : m_mx(create_mutex_(NULL, bInitialOwer, static_cast<ws_char_a_t const *>(0), m_bCreated))
        , m_bAbandoned(false)
    {}
    ss_explicit_k process_mutex(ws_char_a_t const *name, ws_bool_t bInitialOwer) winstl_throw_0()
        : m_mx(create_mutex_(NULL, bInitialOwer, name, m_bCreated))
        , m_bAbandoned(false)
    {}
    ss_explicit_k process_mutex(ws_char_w_t const *name, ws_bool_t bInitialOwer) winstl_throw_0()
        : m_mx(create_mutex_(NULL, bInitialOwer, name, m_bCreated))
        , m_bAbandoned(false)
    {}
    ss_explicit_k process_mutex(ws_char_a_t const *name, ws_bool_t bInitialOwer, LPSECURITY_ATTRIBUTES psa) winstl_throw_0()
        : m_mx(create_mutex_(psa, bInitialOwer, name, m_bCreated))
        , m_bAbandoned(false)
    {}
    ss_explicit_k process_mutex(ws_char_w_t const *name, ws_bool_t bInitialOwer, LPSECURITY_ATTRIBUTES psa) winstl_throw_0()
        : m_mx(create_mutex_(psa, bInitialOwer, name, m_bCreated))
        , m_bAbandoned(false)
    {}

    ~process_mutex() winstl_throw_0()
    {
        if(m_mx != NULL)
        {
            ::CloseHandle(m_mx);
        }
    }

#if 0
    void close() winstl_throw_0()
    {
        if(m_mx != NULL)
        {
            CloseHandleSetNull(m_mx);
        }
    }
#endif /* 0 */


public:
    void lock() winstl_throw_0()
    {
        DWORD   dwRes   =   ::WaitForSingleObject(m_mx, INFINITE);

        m_bAbandoned = (dwRes == WAIT_ABANDONED);
    }
    ws_bool_t lock(ws_dword_t wait) winstl_throw_0()
    {
        DWORD   dwRes   =   ::WaitForSingleObject(m_mx, wait);

        m_bAbandoned = (dwRes == WAIT_ABANDONED);

        return (dwRes == WAIT_OBJECT_0);
    }
    ws_bool_t try_lock()
    {
        return lock(0);
    }
    void unlock() winstl_throw_0()
    {
        ::ReleaseMutex(m_mx);
    }

public:
    HANDLE  handle()
    {
        return m_mx;
    }

public:
    ws_bool_t created() const
    {
        return m_bCreated;
    }

    ws_bool_t abandoned() const
    {
        return m_bAbandoned;
    }


// Implementation
private:
    static HANDLE create_mutex_(LPSECURITY_ATTRIBUTES psa, ws_bool_t bInitialOwner, ws_char_a_t const *name, ws_bool_t &bCreated)
    {
        HANDLE  mx  =   ::CreateMutexA(psa, bInitialOwner, name);

        bCreated = (mx != NULL && ::GetLastError() != ERROR_ALREADY_EXISTS);

        return mx;
    }
    static HANDLE create_mutex_(LPSECURITY_ATTRIBUTES psa, ws_bool_t bInitialOwner, ws_char_w_t const *name, ws_bool_t &bCreated)
    {
        HANDLE  mx  =   ::CreateMutexW(psa, bInitialOwner, name);

        bCreated = (mx != NULL && ::GetLastError() != ERROR_ALREADY_EXISTS);

        return mx;
    }
    static HANDLE open_mutex_(ws_dword_t access, ws_bool_t bInheritHandle, ws_char_a_t const *name, ws_bool_t &bCreated)
    {
        HANDLE  mx  =   ::OpenMutexA(access, bInheritHandle, name);

        bCreated = (mx != NULL && ::GetLastError() != ERROR_ALREADY_EXISTS);

        return mx;
    }
    static HANDLE open_mutex_(ws_dword_t access, ws_bool_t bInheritHandle, ws_char_w_t const *name, ws_bool_t &bCreated)
    {
        HANDLE  mx  =   ::OpenMutexW(access, bInheritHandle, name);

        bCreated = (mx != NULL && ::GetLastError() != ERROR_ALREADY_EXISTS);

        return mx;
    }

// Members
private:
    HANDLE      m_mx;           // The underlying mutex object
    ws_bool_t   m_bCreated;     // Did this object (thread) create the underlying mutex object
    ws_bool_t   m_bAbandoned;   // Did the previous owner abandon the underlying mutex object

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

/* 
 * Control shims
 */

#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 */





inline void lock_instance(winstl_ns_qual(process_mutex) &mx)
{
    mx.lock();
}

inline void unlock_instance(winstl_ns_qual(process_mutex) &mx)
{
    mx.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 /* __STLSOFT_COMPILER_IS_BORLAND */
# endif /* _STLSOFT_NO_NAMESPACE */
#endif /* !_WINSTL_NO_NAMESPACE */

/* 
 * lock_traits (for the compilers that do not support Koenig Lookup)
 */

// class lock_traits
struct process_mutex_lock_traits
{
public:
    typedef process_mutex                lock_type;
    typedef process_mutex_lock_traits    class_type;

// Operations
public:
    static void lock(process_mutex &c)
    {
        lock_instance(c);
    }

    static void unlock(process_mutex &c)
    {
        unlock_instance(c);
    }
};

// Unit-testing

#ifdef STLSOFT_UNITTEST

namespace unittest
{
    ss_bool_t test_winstl_process_mutex(unittest_reporter *r)
    {
        using stlsoft::unittest::unittest_initialiser;

        ss_bool_t               bSuccess    =   true;

        unittest_initialiser    init(r, "WinSTL", "process_mutex", __FILE__);

        process_mutex   mx_r(true);

        mx_r.lock();
        if(!mx_r.try_lock())
        {
            r->report("process_mutex could not lock recursively ", __LINE__);
            bSuccess = false;
        }
        else
        {
            mx_r.unlock();
        }
        mx_r.unlock();

        process_mutex   mx_named("STLSoft.WinSTL.process_mutex");

        mx_named.lock();
        if(!mx_named.try_lock())
        {
            r->report("process_mutex could not lock recursively ", __LINE__);
            mx_named.unlock();
            bSuccess = false;
        }
        mx_named.unlock();

        return bSuccess;
    }

    unittest_registrar    unittest_winstl_process_mutex(test_winstl_process_mutex);

} // namespace unittest

#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_H_WINSTL_PROCESS_MUTEX */

/* 

STLSoft Libraries documentation © Synesis Software Pty Ltd, 2001-2004