AutoLock.h

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//     ____   ______ __
//    / __ \ / ____// /
//   / /_/ // /    / /
//  / ____// /___ / /___   PixInsight Class Library
// /_/     \____//_____/   PCL 2.7.0
// ----------------------------------------------------------------------------
// pcl/AutoLock.h - Released 2024-06-18T15:48:54Z
// ----------------------------------------------------------------------------
// This file is part of the PixInsight Class Library (PCL).
// PCL is a multiplatform C++ framework for development of PixInsight modules.
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// ----------------------------------------------------------------------------
 
#ifndef __PCL_AutoLock_h
#define __PCL_AutoLock_h
 
 
#include <pcl/Defs.h>
#include <pcl/Diagnostics.h>
 
#include <pcl/Atomic.h>
#include <pcl/Mutex.h>
 
namespace pcl
{
 
// ----------------------------------------------------------------------------
 
class PCL_CLASS AutoLock
{
public:
 
   explicit AutoLock( pcl::Mutex& mutex )
      : m_mutex( &mutex )
   {
      Lock();
   }
 
   AutoLock( AutoLock&& x )
      : m_mutex( x.m_mutex )
      , m_lock( x.m_lock )
   {
      x.m_mutex = nullptr;
   }
 
   ~AutoLock()
   {
      Unlock();
      m_mutex = nullptr;
   }
 
   AutoLock( const AutoLock& ) = delete;
 
   AutoLock& operator =( const AutoLock& ) = delete;
 
   AutoLock& operator =( AutoLock&& ) = delete;
 
   void Lock()
   {
      if ( m_mutex != nullptr )
         if ( m_lock.TestAndSet( 0, 1 ) )
            m_mutex->Lock();
   }
 
   void Unlock()
   {
      if ( m_mutex != nullptr )
         if ( m_lock.TestAndSet( 1, 0 ) )
            m_mutex->Unlock();
   }
 
private:
 
   pcl::Mutex* m_mutex = nullptr;
   AtomicInt   m_lock;
};
 
// ----------------------------------------------------------------------------
 
class PCL_CLASS AutoLockCounter
{
public:
 
   explicit AutoLockCounter( pcl::Mutex& mutex, AtomicInt& count, int limit )
      : m_mutex( &mutex )
      , m_count( &count )
      , m_lock( 0 )
   {
      if ( m_count->FetchAndAdd( 1 ) >= limit-1 )
      {
         Lock();
         if ( m_count->Load() < limit )
            Unlock();
      }
   }
 
   AutoLockCounter( AutoLockCounter&& x )
      : m_mutex( x.m_mutex )
      , m_count( x.m_count )
      , m_lock( x.m_lock )
   {
      x.m_mutex = nullptr;
      x.m_count = nullptr;
   }
 
   ~AutoLockCounter()
   {
      Unlock();
      m_mutex = nullptr;
      if ( m_count != nullptr )
      {
         m_count->Decrement();
         m_count = nullptr;
      }
   }
 
   AutoLockCounter( const AutoLockCounter& ) = delete;
 
   AutoLockCounter& operator =( const AutoLockCounter& ) = delete;
 
   AutoLockCounter& operator =( AutoLockCounter&& ) = delete;
 
   void Lock()
   {
      if ( m_mutex != nullptr )
         if ( m_lock.TestAndSet( 0, 1 ) )
            m_mutex->Lock();
   }
 
   void Unlock()
   {
      if ( m_mutex != nullptr )
         if ( m_lock.TestAndSet( 1, 0 ) )
            m_mutex->Unlock();
   }
 
private:
 
   pcl::Mutex* m_mutex = nullptr;
   AtomicInt*  m_count = nullptr;
   AtomicInt   m_lock;
};
 
// ----------------------------------------------------------------------------
 
#define Synchronized( mutex, code )    \
{                                      \
   pcl::AutoLock _________( mutex );   \
   code                                \
}
 
// ----------------------------------------------------------------------------
 
} // pcl
 
#endif   // __PCL_AutoLock_h
 
// ----------------------------------------------------------------------------
// EOF pcl/AutoLock.h - Released 2024-06-18T15:48:54Z