~drizzle-trunk/drizzle/development

/* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-

 *  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:

 *

 *  Copyright (C) 2009 Sun Microsystems

 *  Copyright 2005-2008 Intel Corporation.  All Rights Reserved.

 *

 *  This program is free software; you can redistribute it and/or modify

 *  it under the terms of the GNU General Public License as published by

 *  the Free Software Foundation; version 2 of the License.

 *

 *  This program is distributed in the hope that it will be useful,

 *  but WITHOUT ANY WARRANTY; without even the implied warranty of

 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 *  GNU General Public License for more details.

 *

 *  You should have received a copy of the GNU General Public License

 *  along with this program; if not, write to the Free Software

 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

 */

#ifndef DRIZZLED_ATOMICS_H

#define DRIZZLED_ATOMICS_H

# if defined(__SUNPRO_CC)

#  include <drizzled/atomic/sun_studio.h>

# endif

# if !defined(__ICC) && (defined(HAVE_GCC_ATOMIC_BUILTINS) || defined(__SUNPRO_CC))

#  include <drizzled/atomic/gcc_traits.h>

#  define ATOMIC_TRAITS internal::gcc_traits

# else  /* use pthread impl */

#  define ATOMIC_TRAITS internal::pthread_traits

# endif

# if (SIZEOF_SIZE_T >= SIZEOF_LONG_LONG) || (!defined(HAVE_GCC_ATOMIC_BUILTINS) || !defined(__SUNPRO_CC))

#  include <pthread.h>

#  include <drizzled/atomic/pthread_traits.h>

# endif

namespace drizzled {

namespace internal {

template<typename I>            // Primary template

struct atomic_base {

  volatile I my_value;

};

template<typename I, typename D, typename T >

class atomic_impl: private atomic_base<I>

{

  T traits;

public:

  typedef I value_type;

  value_type fetch_and_add( D addend )

  {

    return traits.fetch_and_add(&this->my_value, addend);

  }

  value_type fetch_and_increment()

  {

    return traits.fetch_and_increment(&this->my_value);

  }

  value_type fetch_and_decrement()

  {

    return traits.fetch_and_decrement(&this->my_value);

  }

  value_type fetch_and_store( value_type value )

  {

    return traits.fetch_and_store(&this->my_value, value);

  }

  value_type compare_and_swap( value_type value, value_type comparand )

  {

    return traits.compare_and_swap(&this->my_value, value, comparand);

  }

  operator value_type() const volatile

  {

    return traits.fetch(&this->my_value);

  }

  value_type& _internal_reference() const

  {

    return this->my_value;

  }

protected:

  value_type store_with_release( value_type rhs )

  {

    return traits.store_with_release(&this->my_value, rhs);

  }

public:

  value_type operator+=( D addend )

  {

      return fetch_and_add(addend)+addend;

  }

  value_type operator-=( D addend )

  {

    // Additive inverse of addend computed using binary minus,

    // instead of unary minus, for sake of avoiding compiler warnings.

    return operator+=(D(0)-addend);

  }

  value_type operator++() {

    return fetch_and_add(1)+1;

  }

  value_type operator--() {

    return fetch_and_add(D(-1))-1;

  }

  value_type operator++(int) {

    return fetch_and_add(1);

  }

  value_type operator--(int) {

    return fetch_and_add(D(-1));

  }

};

} /* namespace internal */

//! Primary template for atomic.

/** See the Reference for details.

    @ingroup synchronization */

template<typename T>

struct atomic {

};

/* *INDENT-OFF* */

#define __DRIZZLE_DECL_ATOMIC(T)                                        \

  template<> struct atomic<T>                                           \

  : internal::atomic_impl<T,T,ATOMIC_TRAITS<T,T> > {                    \

    atomic<T>() : internal::atomic_impl<T,T,ATOMIC_TRAITS<T,T> >() {}   \

    T operator=( T rhs ) { return store_with_release(rhs); }            \

  };

/* *INDENT-ON* */

__DRIZZLE_DECL_ATOMIC(long)

__DRIZZLE_DECL_ATOMIC(unsigned long)

__DRIZZLE_DECL_ATOMIC(unsigned int)

__DRIZZLE_DECL_ATOMIC(int)

__DRIZZLE_DECL_ATOMIC(unsigned short)

__DRIZZLE_DECL_ATOMIC(short)

__DRIZZLE_DECL_ATOMIC(char)

__DRIZZLE_DECL_ATOMIC(signed char)

__DRIZZLE_DECL_ATOMIC(unsigned char)

__DRIZZLE_DECL_ATOMIC(bool)

/* 32-bit platforms don't have a GCC atomic operation for 64-bit types,

 * so we'll use pthread locks to handler 64-bit types on that platforms

 */

/* *INDENT-OFF* */

#  if SIZEOF_SIZE_T >= SIZEOF_LONG_LONG

__DRIZZLE_DECL_ATOMIC(long long)

__DRIZZLE_DECL_ATOMIC(unsigned long long)

#  else

#   define __DRIZZLE_DECL_ATOMIC64(T)                                   \

  template<> struct atomic<T>                                           \

  : internal::atomic_impl<T,T,internal::pthread_traits<T,T> > {         \

    atomic<T>()                                                         \

      : internal::atomic_impl<T,T,internal::pthread_traits<T,T> >() {}  \

    T operator=( T rhs ) { return store_with_release(rhs); }            \

  };

__DRIZZLE_DECL_ATOMIC64(long long)

__DRIZZLE_DECL_ATOMIC64(unsigned long long)

#  endif

/* *INDENT-ON* */

}

#endif /* DRIZZLED_ATOMICS_H */