/*=========================================================================

  Program:   Visualization Toolkit
  Module:    vtkAtomic.cxx

  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
  All rights reserved.
  See Copyright.txt or http://www.kitware.com/Copyright.htm for details.

     This software is distributed WITHOUT ANY WARRANTY; without even
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
     PURPOSE.  See the above copyright notice for more information.

=========================================================================*/

#include "vtkAtomic.h"


#if !defined(VTK_GCC_ATOMICS_32) && !defined(VTK_APPLE_ATOMICS_32) &&\
    !defined(VTK_WINDOWS_ATOMICS_32)
# define VTK_LOCK_BASED_ATOMICS_32
#endif

#if !defined(VTK_GCC_ATOMICS_64) && !defined(VTK_APPLE_ATOMICS_64) &&\
    !defined(VTK_WINDOWS_ATOMICS_64)
# define VTK_LOCK_BASED_ATOMICS_64
#endif


#if defined(VTK_WINDOWS_ATOMICS_32) || defined(VTK_WINDOWS_ATOMICS_64)
# include "vtkWindows.h"
#endif

#if defined(VTK_LOCK_BASED_ATOMICS_32) || defined(VTK_LOCK_BASED_ATOMICS_64)

#include "vtkSimpleCriticalSection.h"

class CriticalSectionGuard
{
public:
  CriticalSectionGuard(vtkSimpleCriticalSection &cs) : CriticalSection(cs)
  {
    this->CriticalSection.Lock();
  }

  ~CriticalSectionGuard()
  {
    this->CriticalSection.Unlock();
  }

private:
  // not copyable
  CriticalSectionGuard(const CriticalSectionGuard&);
  void operator=(const CriticalSectionGuard&);

  vtkSimpleCriticalSection &CriticalSection;
};

#if defined(VTK_LOCK_BASED_ATOMICS_64)
detail::AtomicOps<8>::atomic_type::atomic_type(vtkTypeInt64 init)
  : var(init)
{
  this->csec = new vtkSimpleCriticalSection;
}

detail::AtomicOps<8>::atomic_type::~atomic_type()
{
  delete this->csec;
}
#endif

#if defined(VTK_LOCK_BASED_ATOMICS_32)
detail::AtomicOps<4>::atomic_type::atomic_type(vtkTypeInt32 init)
  : var(init)
{
  this->csec = new vtkSimpleCriticalSection;
}

detail::AtomicOps<4>::atomic_type::~atomic_type()
{
  delete this->csec;
}
#endif

#endif // VTK_LOCK_BASED_ATOMICS


namespace detail
{

#if defined(VTK_WINDOWS_ATOMICS_64) || defined(VTK_LOCK_BASED_ATOMICS_64)

vtkTypeInt64 AtomicOps<8>::AddAndFetch(atomic_type *ref, vtkTypeInt64 val)
{
#if defined(VTK_WINDOWS_ATOMICS_64)
# if defined(VTK_HAS_INTERLOCKEDADD)
  return InterlockedAdd64(ref, val);
# else
  return InterlockedExchangeAdd64(ref, val) + val;
# endif
#else
  CriticalSectionGuard csg(*ref->csec);
  return ref->var += val;
#endif
}

vtkTypeInt64 AtomicOps<8>::SubAndFetch(atomic_type *ref, vtkTypeInt64 val)
{
#if defined(VTK_WINDOWS_ATOMICS_64)
# if defined(VTK_HAS_INTERLOCKEDADD)
  return InterlockedAdd64(ref, -val);
# else
  return InterlockedExchangeAdd64(ref, -val) - val;
# endif
#else
  CriticalSectionGuard csg(*ref->csec);
  return ref->var -= val;
#endif
}

vtkTypeInt64 AtomicOps<8>::PreIncrement(atomic_type *ref)
{
#if defined(VTK_WINDOWS_ATOMICS_64)
  return InterlockedIncrement64(ref);
#else
  CriticalSectionGuard csg(*ref->csec);
  return ++(ref->var);
#endif
}

vtkTypeInt64 AtomicOps<8>::PreDecrement(atomic_type *ref)
{
#if defined(VTK_WINDOWS_ATOMICS_64)
  return InterlockedDecrement64(ref);
#else
  CriticalSectionGuard csg(*ref->csec);
  return --(ref->var);
#endif
}

vtkTypeInt64 AtomicOps<8>::PostIncrement(atomic_type *ref)
{
#if defined(VTK_WINDOWS_ATOMICS_64)
  vtkTypeInt64 val = InterlockedIncrement64(ref);
  return --val;
#else
  CriticalSectionGuard csg(*ref->csec);
  return (ref->var)++;
#endif
}

vtkTypeInt64 AtomicOps<8>::PostDecrement(atomic_type *ref)
{
#if defined(VTK_WINDOWS_ATOMICS_64)
  vtkTypeInt64 val = InterlockedDecrement64(ref);
  return ++val;
#else
  CriticalSectionGuard csg(*ref->csec);
  return (ref->var)--;
#endif
}

vtkTypeInt64 AtomicOps<8>::Load(const atomic_type *ref)
{
#if defined(VTK_WINDOWS_ATOMICS_64)
  vtkTypeInt64 val;
  InterlockedExchange64(&val, *ref);
  return val;
#else
  CriticalSectionGuard csg(*ref->csec);
  return ref->var;
#endif
}

void AtomicOps<8>::Store(atomic_type *ref, vtkTypeInt64 val)
{
#if defined(VTK_WINDOWS_ATOMICS_64)
  InterlockedExchange64(ref, val);
#else
  CriticalSectionGuard csg(*ref->csec);
  ref->var = val;
#endif
}

#endif // defined(VTK_WINDOWS_ATOMICS_64) || defined(VTK_LOCK_BASED_ATOMICS_64)


#if defined(VTK_WINDOWS_ATOMICS_32) || defined(VTK_LOCK_BASED_ATOMICS_32)

vtkTypeInt32 AtomicOps<4>::AddAndFetch(atomic_type *ref, vtkTypeInt32 val)
{
#if defined(VTK_WINDOWS_ATOMICS_32)
# if defined(VTK_HAS_INTERLOCKEDADD)
  return InterlockedAdd(reinterpret_cast<long*>(ref), val);
# else
  return InterlockedExchangeAdd(reinterpret_cast<long*>(ref), val) + val;
# endif
#else
  CriticalSectionGuard csg(*ref->csec);
  return ref->var += val;
#endif
}

vtkTypeInt32 AtomicOps<4>::SubAndFetch(atomic_type *ref, vtkTypeInt32 val)
{
#if defined(VTK_WINDOWS_ATOMICS_32)
# if defined(VTK_HAS_INTERLOCKEDADD)
  return InterlockedAdd(reinterpret_cast<long*>(ref), -val);
# else
  return InterlockedExchangeAdd(reinterpret_cast<long*>(ref), -val) - val;
# endif
#else
  CriticalSectionGuard csg(*ref->csec);
  return ref->var -= val;
#endif
}

vtkTypeInt32 AtomicOps<4>::PreIncrement(atomic_type *ref)
{
#if defined(VTK_WINDOWS_ATOMICS_32)
  return InterlockedIncrement(reinterpret_cast<long*>(ref));
#else
  CriticalSectionGuard csg(*ref->csec);
  return ++(ref->var);
#endif
}

vtkTypeInt32 AtomicOps<4>::PreDecrement(atomic_type *ref)
{
#if defined(VTK_WINDOWS_ATOMICS_32)
  return InterlockedDecrement(reinterpret_cast<long*>(ref));
#else
  CriticalSectionGuard csg(*ref->csec);
  return --(ref->var);
#endif
}

vtkTypeInt32 AtomicOps<4>::PostIncrement(atomic_type *ref)
{
#if defined(VTK_WINDOWS_ATOMICS_32)
  vtkTypeInt32 val = InterlockedIncrement(reinterpret_cast<long*>(ref));
  return --val;
#else
  CriticalSectionGuard csg(*ref->csec);
  return (ref->var)++;
#endif
}

vtkTypeInt32 AtomicOps<4>::PostDecrement(atomic_type *ref)
{
#if defined(VTK_WINDOWS_ATOMICS_32)
  vtkTypeInt32 val = InterlockedDecrement(reinterpret_cast<long*>(ref));
  return ++val;
#else
  CriticalSectionGuard csg(*ref->csec);
  return (ref->var)--;
#endif
}

vtkTypeInt32 AtomicOps<4>::Load(const atomic_type *ref)
{
#if defined(VTK_WINDOWS_ATOMICS_32)
  long val;
  InterlockedExchange(&val, *ref);
  return val;
#else
  CriticalSectionGuard csg(*ref->csec);
  return ref->var;
#endif
}

void AtomicOps<4>::Store(atomic_type *ref, vtkTypeInt32 val)
{
#if defined(VTK_WINDOWS_ATOMICS_32)
  InterlockedExchange(reinterpret_cast<long*>(ref), val);
#else
  CriticalSectionGuard csg(*ref->csec);
  ref->var = val;
#endif
}

#endif // defined(VTK_WINDOWS_ATOMICS_32) || defined(VTK_LOCK_BASED_ATOMICS_32)

} // namespace detail
