Use thread-safe atomic reference counting (GCC and MSVC). * configure.ac: New --enable-atomic-refcount argument. (octave_allocator): Fix USE_OCTAVE_ALLOCATOR variable assignment. (OCTAVE_CONFIG_INCLUDED): New macro in config.h. * oct-refcount.h (OCTREFCOUNT_ATOMIC_INCREMENT, OCTREFCOUNT_ATOMIC_INCREMENT_POST, OCTREFCOUNT_ATOMIC_DECREMENT, OCTREFCOUNT_ATOMIC_DECREMENT_POST): New macro, defined for MSVC and GCC when USE_ATOMIC_REFCOUNT is defined. (octave_refcount:operator++, octave_refcount::operator--): Use them. (octave_refcount::operator count_type): Cast returned value to volatile. (octave_refcount::direct): Remove unsafe member. * Array.h (Array::make_unique): Delete rep if refcount reaches 0. * Sparse.h (Sparse::make_unique): Delete rep if refcount reaches 0. * Array.h (Array:~Array, Array::operator=): Delete rep only when refcount is excatly 0. * Array.cc (Array::clear): Likewise. * Sparse.cc (Sparse::~Sparse, Sparse::operator=): Likewise. * SparseCmplxQR.h (SparseCmplxQR::~SparseCmplxQR, SparseCmplxQR::operator=): Likewise. * SparseQR.h (SparseQR::~SparseQR, SparseQR::operator=): Likewise. * sparse-base-chol.h (sparse_base_chol::~sparse_base_chol, sparse_base_chol::operator): Likewise. * dim-vector.h (oct-refcount.h): New included header. (dim_vector::make_unique, dim_vector::resize): Use OCTREFCOUNT_ATOMIC_DECREMENT macro and delete rep when refcount reaches 0. (dim_vector::dim_vector): Use OCTREFCOUNT_ATOMIC_INCREMENT. (dim_vector::operator=): Use OCTREFCOUNT_ATOMIC_INCREMENT and OCTREFCOUNT_ATOMIC_DECREMENT. (dim_vector::~dim_vector): Use OCTREFCOUNT_ATOMIC_DECREMENT. * oct-mutex.h (oct-refcount.h): New included header. (octave_base_mutex::count): Use octave_refcount class. * gl-render.cc (oct-refcount.h): New included header. * graphics.h.in (oct-refcount.h): Likewise. (base_property::count, base_graphics_toolkit::count, base_graphics_object::count, base_graphics_event::count): Use octave_refcount. (property::~property, property::operator=): Delete rep only when refcountn is excatly 0. * oct-map.h (octave_fields::make_unique): Delete rep when refcount reaches 0. * oct-stream.h (oct-refcount.h): New included header. (octave_base_stream::count): Use octave_refcount class. * ov.h (octave_value::make_unique): Delete rep when refcount reaches 0. * symtab.h (oct-refcount.h): New included header. (symbol_record_rep::count, fcn_info_rep::count): Use octave_refcount class. * DLD-FUNCTIONS/urlwrite.cc (oct-refcount.h): New included header. (curl_handle_rep::count): Use octave_refcount class.

/*

Copyright (C) 1996-2011 John W. Eaton

This file is part of Octave.

Octave 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; either version 3 of the License, or (at your
option) any later version.

Octave 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 Octave; see the file COPYING.  If not, see
<http://www.gnu.org/licenses/>.

*/

#if !defined (octave_tree_jump_h)
#define octave_tree_jump_h 1

class tree_walker;

#include "pt-cmd.h"
#include "symtab.h"

// Break.

class
tree_break_command : public tree_command
{
public:

  tree_break_command (int l = -1, int c = -1)
    : tree_command (l, c) { }

  ~tree_break_command (void) { }

  tree_command *dup (symbol_table::scope_id scope,
                     symbol_table::context_id context) const;

  void accept (tree_walker& tw);

  static int breaking;

private:

  // No copying!

  tree_break_command (const tree_break_command&);

  tree_break_command& operator = (const tree_break_command&);
};

// Continue.

class
tree_continue_command : public tree_command
{
public:

  tree_continue_command (int l = -1, int c = -1)
    : tree_command (l, c) { }

  ~tree_continue_command (void) { }

  tree_command *dup (symbol_table::scope_id scope,
                     symbol_table::context_id context) const;

  void accept (tree_walker& tw);

  static int continuing;

private:

  // No copying!

  tree_continue_command (const tree_continue_command&);

  tree_continue_command& operator = (const tree_continue_command&);
};

// Return.

class
tree_return_command : public tree_command
{
public:

  tree_return_command (int l = -1, int c = -1)
    : tree_command (l, c) { }

  ~tree_return_command (void) { }

  tree_command *dup (symbol_table::scope_id scope,
                     symbol_table::context_id context) const;

  void accept (tree_walker& tw);

  static int returning;

private:

  // No copying!

  tree_return_command (const tree_return_command&);

  tree_return_command& operator = (const tree_return_command&);
};

#endif