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// -*- C++ -*-

// Copyright (C) 2005, 2006, 2007, 2009 Free Software Foundation, Inc.

//

// This file is part of the GNU ISO C++ Library.  This library 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, or (at your option) any later

// version.

// This library 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.

// Under Section 7 of GPL version 3, you are granted additional

// permissions described in the GCC Runtime Library Exception, version

// 3.1, as published by the Free Software Foundation.

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

// a copy of the GCC Runtime Library Exception along with this program;

// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see

// <http://www.gnu.org/licenses/>.

// Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.

// Permission to use, copy, modify, sell, and distribute this software

// is hereby granted without fee, provided that the above copyright

// notice appears in all copies, and that both that copyright notice

// and this permission notice appear in supporting documentation. None

// of the above authors, nor IBM Haifa Research Laboratories, make any

// representation about the suitability of this software for any

// purpose. It is provided "as is" without express or implied

// warranty.

/**

 * @file cc_hash_max_collision_check_resize_trigger_imp.hpp

 * Contains a resize trigger implementation.

 */

PB_DS_CLASS_T_DEC

PB_DS_CLASS_C_DEC::

cc_hash_max_collision_check_resize_trigger(float load) :

  m_load(load),

  m_size(0),

  m_num_col(0),

  m_max_col(0),

  m_resize_needed(false)

{ }

PB_DS_CLASS_T_DEC

inline void

PB_DS_CLASS_C_DEC::

notify_find_search_start()

{ }

PB_DS_CLASS_T_DEC

inline void

PB_DS_CLASS_C_DEC::

notify_find_search_collision()

{ }

PB_DS_CLASS_T_DEC

inline void

PB_DS_CLASS_C_DEC::

notify_find_search_end()

{ }

PB_DS_CLASS_T_DEC

inline void

PB_DS_CLASS_C_DEC::

notify_insert_search_start()

{ m_num_col = 0; }

PB_DS_CLASS_T_DEC

inline void

PB_DS_CLASS_C_DEC::

notify_insert_search_collision()

{ ++m_num_col; }

PB_DS_CLASS_T_DEC

inline void

PB_DS_CLASS_C_DEC::

notify_insert_search_end()

{ calc_resize_needed(); }

PB_DS_CLASS_T_DEC

inline void

PB_DS_CLASS_C_DEC::

notify_erase_search_start()

{ }

PB_DS_CLASS_T_DEC

inline void

PB_DS_CLASS_C_DEC::

notify_erase_search_collision()

{ }

PB_DS_CLASS_T_DEC

inline void

PB_DS_CLASS_C_DEC::

notify_erase_search_end()

{ }

PB_DS_CLASS_T_DEC

inline void

PB_DS_CLASS_C_DEC::

notify_inserted(size_type)

{ }

PB_DS_CLASS_T_DEC

inline void

PB_DS_CLASS_C_DEC::

notify_erased(size_type)

{ m_resize_needed = true; }

PB_DS_CLASS_T_DEC

void

PB_DS_CLASS_C_DEC::

notify_cleared()

{ m_resize_needed = false; }

PB_DS_CLASS_T_DEC

inline bool

PB_DS_CLASS_C_DEC::

is_resize_needed() const

{ return m_resize_needed; }

PB_DS_CLASS_T_DEC

inline bool

PB_DS_CLASS_C_DEC::

is_grow_needed(size_type /*size*/, size_type /*num_used_e*/) const

{ return m_num_col >= m_max_col; }

PB_DS_CLASS_T_DEC

void

PB_DS_CLASS_C_DEC::

notify_resized(size_type new_size)

{

  m_size = new_size;

#ifdef PB_DS_HT_MAP_RESIZE_TRACE_

  std::cerr << "chmccrt::notify_resized "

            << static_cast<unsigned long>(new_size) << std::endl;

#endif 

  calc_max_num_coll();

  calc_resize_needed();

  m_num_col = 0;

}

PB_DS_CLASS_T_DEC

void

PB_DS_CLASS_C_DEC::

calc_max_num_coll()

{

  // max_col <-- \sqrt{2 load \ln( 2 m \ln( m ) ) }

  const double ln_arg = 2 * m_size * std::log(double(m_size));

  m_max_col = size_type(std::ceil(std::sqrt(2 * m_load * std::log(ln_arg))));

#ifdef PB_DS_HT_MAP_RESIZE_TRACE_

  std::cerr << "chmccrt::calc_max_num_coll "

            << static_cast<unsigned long>(m_size) <<    "    "

            << static_cast<unsigned long>(m_max_col) << std::endl;

#endif 

}

PB_DS_CLASS_T_DEC

void

PB_DS_CLASS_C_DEC::

notify_externally_resized(size_type new_size)

{ notify_resized(new_size); }

PB_DS_CLASS_T_DEC

void

PB_DS_CLASS_C_DEC::

swap(PB_DS_CLASS_C_DEC& other)

{

  std::swap(m_load, other.m_load);

  std::swap(m_size, other.m_size);

  std::swap(m_num_col, other.m_num_col);

  std::swap(m_max_col, other.m_max_col);

  std::swap(m_resize_needed, other.m_resize_needed);

}

PB_DS_CLASS_T_DEC

inline float

PB_DS_CLASS_C_DEC::

get_load() const

{

  PB_DS_STATIC_ASSERT(access, external_load_access);

  return m_load;

}

PB_DS_CLASS_T_DEC

inline void

PB_DS_CLASS_C_DEC::

calc_resize_needed()

{ m_resize_needed = m_resize_needed || m_num_col >= m_max_col; }

PB_DS_CLASS_T_DEC

void

PB_DS_CLASS_C_DEC::

set_load(float load)

{

  PB_DS_STATIC_ASSERT(access, external_load_access);

  m_load = load;

  calc_max_num_coll();

  calc_resize_needed();

}