critsec.h

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/*
 * critsec.h
 *
 * Critical section mutex class.
 *
 * Portable Windows Library
 *
 * Copyright (C) 2004 Post Increment
 *
 * The contents of this file are subject to the Mozilla Public License
 * Version 1.0 (the "License"); you may not use this file except in
 * compliance with the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS"
 * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
 * the License for the specific language governing rights and limitations
 * under the License.
 *
 * The Original Code is Portable Windows Library.
 *
 * The Initial Developer of the Original Code is Post Increment
 *
 * Contributor(s): ______________________________________.
 *
 * $Revision: 30087 $
 * $Author: rjongbloed $
 * $Date: 2013-07-01 18:04:23 +1000 (Mon, 01 Jul 2013) $
 */

#ifndef PTLIB_CRITICALSECTION_H
#define PTLIB_CRITICALSECTION_H

#include <ptlib/psync.h>

#if defined(SOLARIS) && !defined(__GNUC__)
#include <atomic.h>
#endif

#if P_HAS_ATOMIC_INT

#if defined(__GNUC__)
#  if __GNUC__ >= 4 && __GNUC_MINOR__ >= 2
#     include <ext/atomicity.h>
#  else
#     include <bits/atomicity.h>
#  endif
#endif

#if P_NEEDS_GNU_CXX_NAMESPACE
#define EXCHANGE_AND_ADD(v,i)   __gnu_cxx::__exchange_and_add(v,i)
#else
#define EXCHANGE_AND_ADD(v,i)   __exchange_and_add(v,i)
#endif

#endif // P_HAS_ATOMIC_INT


#ifdef _WIN32

class PCriticalSection : public PSync
{
  PCLASSINFO(PCriticalSection, PSync);

  public:
    PCriticalSection();

    PCriticalSection(const PCriticalSection &);

    ~PCriticalSection();

    PCriticalSection & operator=(const PCriticalSection &) { return *this; }

    PObject * Clone() const
    {
      return new PCriticalSection();
    }

    virtual void Wait();
    inline void Enter() { Wait(); }

    virtual PBoolean Wait(
      const PTimeInterval & timeout // Amount of time to wait.
    );

    virtual void Signal();
    inline void Leave() { Signal(); }

    bool Try();


#include "msos/ptlib/critsec.h"

};

#endif

typedef PWaitAndSignal PEnterAndLeave;


class PAtomicBase
{
  public:
#if defined(_WIN32)
    typedef long IntegerType;
#elif defined(_STLP_INTERNAL_THREADS_H) && defined(_STLP_ATOMIC_INCREMENT) && defined(_STLP_ATOMIC_DECREMENT)
    typedef __stl_atomic_t IntegerType;
#elif defined(SOLARIS) && !defined(__GNUC__)
    typedef uint32_t IntegerType;
#elif defined(__GNUC__) && P_HAS_ATOMIC_INT
    typedef _Atomic_word IntegerType;
#else
    typedef int IntegerType;
  protected:
    pthread_mutex_t m_mutex;
#endif

  protected:
    IntegerType m_value;

    explicit PAtomicBase(IntegerType value);

  public:
    ~PAtomicBase();
};



class PAtomicInteger : PAtomicBase
{
  public:
    typedef PAtomicBase::IntegerType IntegerType;

    explicit PAtomicInteger(
      IntegerType value = 0                     
    ) : PAtomicBase(value) { }

    __inline operator IntegerType() const { return m_value; }

    __inline PAtomicInteger & operator=(IntegerType value) { m_value = value; return *this; }

    void SetValue(
      IntegerType value  
    ) { m_value = value; }

    __inline bool IsZero() const { return m_value == 0; }

    __inline bool operator!() const { return m_value == 0; }

    IntegerType operator++();

    IntegerType operator++(int);

    IntegerType operator--();

    IntegerType operator--(int);


    friend __inline ostream & operator<<(ostream & strm, const PAtomicInteger & i)
    {
      return strm << i.m_value;
    }
};


class PAtomicBoolean : PAtomicBase
{
  public:
    explicit PAtomicBoolean(
      bool value = false  
    ) : PAtomicBase(value ? 1 : 0) { }

    __inline operator bool() const { return m_value != 0; }

    __inline PAtomicBoolean & operator=(bool value) { m_value = value ? 1 : 0; return *this; }

    __inline bool operator!() const { return m_value == 0; }

    bool TestAndSet(
      bool value  
    );


    friend __inline ostream & operator<<(ostream & strm, const PAtomicBoolean & b)
    {
      return strm << (b.m_value != 0 ? "true" : "false");
    }
};


#if defined(_WIN32) || defined(DOC_PLUS_PLUS)
__inline PAtomicBase::PAtomicBase(IntegerType value) : m_value(value) { }
__inline PAtomicBase::~PAtomicBase()                                  { }
__inline PAtomicInteger::IntegerType PAtomicInteger::operator++()     { return InterlockedIncrement  (&m_value); }
__inline PAtomicInteger::IntegerType PAtomicInteger::operator++(int)  { return InterlockedExchangeAdd(&m_value, 1); }
__inline PAtomicInteger::IntegerType PAtomicInteger::operator--()     { return InterlockedDecrement  (&m_value); }
__inline PAtomicInteger::IntegerType PAtomicInteger::operator--(int)  { return InterlockedExchangeAdd(&m_value, -1); }
__inline bool PAtomicBoolean::TestAndSet(bool value)                  { return InterlockedExchange   (&m_value, value) != 0; }
#elif defined(_STLP_INTERNAL_THREADS_H) && defined(_STLP_ATOMIC_INCREMENT) && defined(_STLP_ATOMIC_DECREMENT)
__inline PAtomicBase::PAtomicBase(IntegerType value) : m_value(value) { }
__inline PAtomicBase::~PAtomicBase()                                  { }
__inline PAtomicInteger::IntegerType PAtomicInteger::operator++()     { return _STLP_ATOMIC_INCREMENT(&m_value); }
__inline PAtomicInteger::IntegerType PAtomicInteger::operator++(int)  { return _STLP_ATOMIC_INCREMENT(&m_value)-1; }
__inline PAtomicInteger::IntegerType PAtomicInteger::operator--()     { return _STLP_ATOMIC_DECREMENT(&m_value); }
__inline PAtomicInteger::IntegerType PAtomicInteger::operator--(int)  { return _STLP_ATOMIC_DECREMENT(&m_value)+1; }
__inline bool PAtomicBoolean::TestAndSet(bool value)                  { return _STLP_ATOMIC_EXCHANGE (&m_value, value) != 0; }
#elif defined(SOLARIS) && !defined(__GNUC__)
__inline PAtomicBase::PAtomicBase(IntegerType value) : m_value(value) { }
__inline PAtomicBase::~PAtomicBase()                                  { }
__inline PAtomicInteger::IntegerType PAtomicInteger::operator++()     { return atomic_add_32_nv(&m_value,  1); }
__inline PAtomicInteger::IntegerType PAtomicInteger::operator++(int)  { return atomic_add_32_nv(&m_value,  1)-1; }
__inline PAtomicInteger::IntegerType PAtomicInteger::operator--()     { return atomic_add_32_nv(&m_value, -1); }
__inline PAtomicInteger::IntegerType PAtomicInteger::operator--(int)  { return atomic_add_32_nv(&m_value, -1)+1; }
__inline bool PAtomicBoolean::TestAndSet(bool value)                  { return atomic_swap_32  (&m_value, value) != 0; }
#elif defined(__GNUC__) && P_HAS_ATOMIC_INT
__inline PAtomicBase::PAtomicBase(IntegerType value) : m_value(value) { }
__inline PAtomicBase::~PAtomicBase()                                  { }
__inline PAtomicInteger::IntegerType PAtomicInteger::operator++()     { return EXCHANGE_AND_ADD(&m_value,  1)+1; }
__inline PAtomicInteger::IntegerType PAtomicInteger::operator++(int)  { return EXCHANGE_AND_ADD(&m_value,  1); }
__inline PAtomicInteger::IntegerType PAtomicInteger::operator--()     { return EXCHANGE_AND_ADD(&m_value, -1)-1; }
__inline PAtomicInteger::IntegerType PAtomicInteger::operator--(int)  { return EXCHANGE_AND_ADD(&m_value, -1); }
__inline bool PAtomicBoolean::TestAndSet(bool value)                  { IntegerType previous = value ? __sync_fetch_and_or(&m_value, 1) : __sync_fetch_and_and(&m_value, 0); return previous != 0; }
#else
__inline PAtomicBase::PAtomicBase(IntegerType value) : m_value(value) { pthread_mutex_init(&m_mutex, NULL); }
__inline PAtomicBase::~PAtomicBase()                                  { pthread_mutex_destroy(&m_mutex); }
__inline PAtomicInteger::IntegerType PAtomicInteger::operator++()     { pthread_mutex_lock(&m_mutex); int retval = ++m_value; pthread_mutex_unlock(&m_mutex); return retval; }
__inline PAtomicInteger::IntegerType PAtomicInteger::operator++(int)  { pthread_mutex_lock(&m_mutex); int retval = m_value++; pthread_mutex_unlock(&m_mutex); return retval; }
__inline PAtomicInteger::IntegerType PAtomicInteger::operator--()     { pthread_mutex_lock(&m_mutex); int retval = --m_value; pthread_mutex_unlock(&m_mutex); return retval; }
__inline PAtomicInteger::IntegerType PAtomicInteger::operator--(int)  { pthread_mutex_lock(&m_mutex); int retval = m_value--; pthread_mutex_unlock(&m_mutex); return retval; }
__inline bool PAtomicBoolean::TestAndSet(bool value)                  { pthread_mutex_lock(&m_mutex); int retval = m_value; m_value = value; pthread_mutex_unlock(&m_mutex); return retval != 0; }
#endif


#endif // PTLIB_CRITICALSECTION_H


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