// unique_ptr implementation -*- C++ -*-

// Copyright (C) 2007 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 2, 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.

// You should have received a copy of the GNU General Public License
// along with this library; see the file COPYING.  If not, write to
// the Free Software Foundation, 51 Franklin Street, Fifth Floor,
// Boston, MA 02110-1301, USA.

// As a special exception, you may use this file as part of a free software
// library without restriction.  Specifically, if other files instantiate
// templates or use macros or inline functions from this file, or you compile
// this file and link it with other files to produce an executable, this
// file does not by itself cause the resulting executable to be covered by
// the GNU General Public License.  This exception does not however
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.

/** @file stl_unqiue_ptr.h
 *  This is an internal header file, included by other library headers.
 *  You should not attempt to use it directly.
 */

#ifndef _STL_UNIIUE_PTR_H
#define _STL_UNIQUE_PTR_H 1

#ifndef __GXX_EXPERIMENTAL_CXX0X__
# include <c++0x_warning.h>
#endif

#include <bits/c++config.h>
#include <debug/debug.h>
#include <type_traits>
#include <utility>
#include <tuple>

namespace std {
 
  template <class _Tp> 
    struct default_delete {      
      default_delete() {}
      template <class _Up> default_delete(const default_delete<_Up>&) {}
      void operator()(_Tp* __ptr) const {
        static_assert(sizeof(_Tp)>0, "can't delete pointer to incomplete type");
        delete __ptr;
      }
    };

  template <class _Tp> 
    struct default_delete<_Tp[]> {
      void operator()(_Tp* __ptr) const {
        static_assert(sizeof(_Tp)>0, "can't delete pointer to incomplete type");
        delete [] __ptr;
      }
    };

  template <class _Tp, size_t _Nm> 
    struct default_delete<_Tp[_Nm]> {
      void operator()(_Tp* __ptr, size_t) const {
        static_assert(sizeof(_Tp)>0, "can't delete pointer to incomplete type");
        delete [] __ptr;
      }
    };
    
  template <class _Tp, class _Tp_Deleter = default_delete<_Tp>> 
    class unique_ptr {
      typedef _Tp* pointer;
      typedef unique_ptr<_Tp, _Tp_Deleter> __this_type;
      typedef std::tuple<pointer,_Tp_Deleter> __tuple_type;
      typedef __tuple_type __this_type::* __unspecified_bool_type;
      typedef pointer __this_type::* __unspecified_pointer_type;
    public:
      typedef _Tp         element_type;      
      typedef _Tp_Deleter deleter_type;
    
      // constructors
      unique_ptr() : _M_t(pointer(), deleter_type()) 
      {static_assert(!std::is_pointer<deleter_type>::value, 
          "constructed with null function pointer deleter");}
      
      explicit unique_ptr(pointer __p) : _M_t(__p, deleter_type()) 
      {static_assert(!std::is_pointer<deleter_type>::value, 
          "constructed with null function pointer deleter");}
    
      unique_ptr(pointer __p, 
          typename std::conditional<std::is_reference<deleter_type>::value, 
            deleter_type, const deleter_type&>::type __d) 
      : _M_t(__p, __d) {}
      
      unique_ptr(pointer __p, 
          typename std::remove_reference<deleter_type>::type && __d) 
      : _M_t(std::move(__p), std::move(__d)) 
      { static_assert(!std::is_reference<deleter_type>::value, 
          "rvalue deleter bound to reference"); }
    
      // move constructors
      unique_ptr(unique_ptr && u) 
      : _M_t(u.release(), std::forward<deleter_type>(u.get_deleter())) {}
      
      template <class _Up, class _Up_Deleter> 
        unique_ptr(unique_ptr<_Up, _Up_Deleter> && u) 
        : _M_t(u.release(), std::forward<deleter_type>(u.get_deleter())) {}
        
      // destructor
      ~unique_ptr() { reset(); }
    
      // assignment
      unique_ptr& operator=(unique_ptr&& u) { 
        reset(u.release()); 
        get_deleter() = std::move(u.get_deleter()); 
        return *this; 
      }
      
      template <class _Up, class _Up_Deleter> 
        unique_ptr& operator=(unique_ptr<_Up, _Up_Deleter>&& u) { 
          reset(u.release()); 
          get_deleter() = std::move(u.get_deleter()); 
          return *this;
        }
      
      unique_ptr& operator=(__unspecified_pointer_type) 
      { reset(); return *this;}
    
      // observers
      typename std::add_lvalue_reference<element_type>::type operator*() const 
      { _GLIBCXX_DEBUG_ASSERT(get() != 0); return *get(); }
      
      pointer operator->() const 
      { _GLIBCXX_DEBUG_ASSERT(get() != 0); return get(); }
      
      pointer get() const { return std::get<0>(_M_t); }      
      
      typename std::add_lvalue_reference<deleter_type>::type 
      get_deleter() { return std::get<1>(_M_t); }
      
      typename std::add_lvalue_reference<
          typename std::add_const<deleter_type>::type
              >::type 
      get_deleter() const { return std::get<1>(_M_t); }    
      
      operator __unspecified_bool_type () const 
      { return get() == 0 ? 0 : &__this_type::_M_t; }
    
      // modifiers
      pointer release() 
      { pointer __p = get(); std::get<0>(_M_t) = 0; return __p; }
      
      void reset(pointer __p = 0) 
      { if (__p != get()) { get_deleter()(get()); std::get<0>(_M_t) = __p; } }
    
      void swap(unique_ptr && __u) { using std::swap; swap(_M_t, __u._M_t); }
      
    private: 
      // disable copy from lvalue
      unique_ptr(const unique_ptr&); //= delete;
      template <class _Up, class _Up_Deleter> 
        unique_ptr(const unique_ptr<_Up, _Up_Deleter>&); //= delete;
      
      // disable assignment from lvalue
      unique_ptr& operator=(const unique_ptr&); //= delete;
      template <class _Up, class _Up_Deleter> 
        unique_ptr& operator=(const unique_ptr<_Up, _Up_Deleter>&); //= delete;
      
    private:
      __tuple_type _M_t;
  };
  
  template <class _Tp, class _Tp_Deleter> 
    class unique_ptr<_Tp[], _Tp_Deleter> {
      typedef _Tp* pointer;
      typedef unique_ptr<_Tp[], _Tp_Deleter> __this_type;
      typedef std::tuple<pointer, _Tp_Deleter> __tuple_type;
      typedef __tuple_type __this_type::* __unspecified_bool_type;
      typedef pointer __this_type::* __unspecified_pointer_type;
    public:
      typedef _Tp         element_type;      
      typedef _Tp_Deleter deleter_type;
    
      // constructors
      unique_ptr() : _M_t(pointer(), deleter_type()) 
      {static_assert(!std::is_pointer<deleter_type>::value, 
          "constructed with null function pointer deleter");}
      
      explicit unique_ptr(pointer __p) : _M_t(__p, deleter_type()) 
      {static_assert(!std::is_pointer<deleter_type>::value, 
          "constructed with null function pointer deleter");}
    
      unique_ptr(pointer __p, 
          typename std::conditional<std::is_reference<deleter_type>::value, 
              deleter_type, const deleter_type&>::type __d) 
      : _M_t(__p, __d) {}
      
      unique_ptr(pointer __p, 
          typename std::remove_reference<deleter_type>::type && __d) 
      : _M_t(std::move(__p), std::move(__d)) 
      { static_assert(!std::is_reference<deleter_type>::value, 
          "rvalue deleter bound to reference"); }
    
      // move constructors
      unique_ptr(unique_ptr && u) 
      : _M_t(u.release(), std::forward<deleter_type>(u.get_deleter())) {}
      
      template <class _Up, class _Up_Deleter> 
        unique_ptr(unique_ptr<_Up, _Up_Deleter> && u) 
      : _M_t(u.release(), std::forward<deleter_type>(u.get_deleter())) {}
        
      // destructor
      ~unique_ptr() { reset(); }
    
      // assignment
      unique_ptr& operator=(unique_ptr&& u) { 
        reset(u.release()); 
        get_deleter() = std::move(u.get_deleter()); 
        return *this; 
      }
      
      template <class _Up, class _Up_Deleter> 
        unique_ptr& operator=(unique_ptr<_Up, _Up_Deleter>&& u) { 
          reset(u.release()); 
          get_deleter() = std::move(u.get_deleter()); 
          return *this;
        }
      
      unique_ptr& operator=(__unspecified_pointer_type) 
      { reset(); return *this;}
    
      // observers
      typename std::add_lvalue_reference<element_type>::type 
      operator[](size_t i) const 
      { _GLIBCXX_DEBUG_ASSERT(get() != 0); return get()[i]; }
            
      pointer get() const { return std::get<0>(_M_t); }      
      
      typename std::add_lvalue_reference<deleter_type>::type 
      get_deleter() { return std::get<1>(_M_t); }
      
      typename std::add_lvalue_reference<
          typename std::add_const<deleter_type>::type
              >::type 
      get_deleter() const { return std::get<1>(_M_t); }    
      
      operator __unspecified_bool_type () const 
      { return get() == 0 ? 0 : &__this_type::_M_t; }
    
      // modifiers
      pointer release() 
      { pointer __p = get(); std::get<0>(_M_t) = 0; return __p; }
      
      void reset(pointer __p = 0) 
      { if (__p != get()) { get_deleter()(get()); std::get<0>(_M_t) = __p;} }
    
      void swap(unique_ptr && __u) { using std::swap; swap(_M_t, __u._M_t); }
      
 
    private:
      // disable copy from lvalue
      unique_ptr(const unique_ptr&); //= delete;
      unique_ptr& operator=(const unique_ptr&); //= delete;
    
      //disable construction from convertible pointer types (N2315 - 20.6.5.3.1) 
      template <class _Up> unique_ptr(_Up*,
        typename std::conditional<std::is_reference<deleter_type>::value, 
          deleter_type, const deleter_type&>::type,
            typename std::enable_if<std::is_convertible<_Up*, 
                pointer>::value>::type* = 0); //= delete;
    
      template <class _Up> unique_ptr(_Up*, 
          typename std::remove_reference<deleter_type>::type&&,
          typename std::enable_if<std::is_convertible<_Up*, 
              pointer>::value>::type* = 0); //= delete;
    
      template <class _Up> explicit unique_ptr(_Up*,
        typename std::enable_if<std::is_convertible<_Up*, 
            pointer>::value>::type* = 0); //= delete;
    
      //disable reset with convertible pointer types (N2315 - 20.6.5.3.3) 
      template <class _Up>
      typename std::enable_if<std::is_convertible<_Up*,
          pointer>::value>::type reset(_Up*); //= delete;
          
    private:
      __tuple_type _M_t;
  };
  
  template <class _Tp, class _Tp_Deleter, size_t _Nm> 
    class unique_ptr<_Tp[_Nm], _Tp_Deleter> {
      typedef _Tp* pointer;
      typedef unique_ptr<_Tp[_Nm], _Tp_Deleter> __this_type;
      typedef std::tuple<pointer, _Tp_Deleter> __tuple_type;
      typedef __tuple_type __this_type::* __unspecified_bool_type;
      typedef pointer __this_type::* __unspecified_pointer_type;
    public:
      typedef _Tp         element_type;      
      typedef _Tp_Deleter deleter_type;
      static const size_t size = _Nm;
      
      // constructors
      unique_ptr() : _M_t(pointer(), deleter_type()) 
      {static_assert(!std::is_pointer<deleter_type>::value, 
          "constructed with null function pointer deleter");}
      
      explicit unique_ptr(pointer __p) : _M_t(__p, deleter_type()) 
      {static_assert(!std::is_pointer<deleter_type>::value, 
          "constructed with null function pointer deleter");}
    
      unique_ptr(pointer __p, 
        typename std::conditional<std::is_reference<deleter_type>::value, 
          deleter_type, const deleter_type&>::type __d) 
      : _M_t(__p, __d) {}
      
      unique_ptr(pointer __p, 
          typename std::remove_reference<deleter_type>::type && __d) 
      : _M_t(std::move(__p), std::move(__d)) 
      { static_assert(!std::is_reference<deleter_type>::value, 
          "rvalue deleter bound to reference"); }
    
      // move constructors
      unique_ptr(unique_ptr && u) 
      : _M_t(u.release(), std::forward<deleter_type>(u.get_deleter())) {}
      
      template <class _Up, class _Up_Deleter> 
        unique_ptr(unique_ptr<_Up, _Up_Deleter> && u) 
        : _M_t(u.release(), std::forward<deleter_type>(u.get_deleter())) {}
        
      // destructor
      ~unique_ptr() { reset(); }
    
      // assignment
      unique_ptr& operator=(unique_ptr&& u) { 
        reset(u.release()); 
        get_deleter() = std::move(u.get_deleter()); 
        return *this; 
      }
      
      template <class _Up, class _Up_Deleter> 
        unique_ptr& operator=(unique_ptr<_Up, _Up_Deleter>&& u) { 
          reset(u.release()); 
          get_deleter() = std::move(u.get_deleter()); 
          return *this;
        }
      
      unique_ptr& operator=(__unspecified_pointer_type) 
      { reset(); return *this;}
    
      // observers
      typename std::add_lvalue_reference<element_type>::type 
      operator[](size_t i) const 
      { _GLIBCXX_DEBUG_ASSERT(get() != 0 && i < _Nm); return get()[i]; }
            
      pointer get() const { return std::get<0>(_M_t); }      
      
      typename std::add_lvalue_reference<deleter_type>::type 
      get_deleter() { return std::get<1>(_M_t); }
      
      typename std::add_lvalue_reference<
          typename std::add_const<deleter_type>::type
              >::type 
      get_deleter() const { return std::get<1>(_M_t); }    
      
      operator __unspecified_bool_type () const 
      { return get() == 0 ? 0 : &__this_type::_M_t; }
    
      // modifiers
      pointer release() 
      { pointer __p = get(); std::get<0>(_M_t) = 0; return __p; }
      
      void reset(pointer __p = 0) 
      { if(__p != get()){ get_deleter()(get(), _Nm); std::get<0>(_M_t) = __p;}}
    
      void swap(unique_ptr && __u) { using std::swap; swap(_M_t, __u._M_t); }      

    private:
      // disable copy from lvalue
      unique_ptr(const unique_ptr&); //= delete;
      unique_ptr& operator=(const unique_ptr&); //= delete;
    
      //disable construction from convertible pointer types (N2315 - 20.6.5.3.1) 
      template <class _Up> unique_ptr(_Up*,
        typename std::conditional<std::is_reference<deleter_type>::value,
            deleter_type, const deleter_type&>::type,
        typename std::enable_if<std::is_convertible<_Up*, 
            pointer>::value>::type* = 0); //= delete;
    
    template <class _Up> unique_ptr(_Up*, 
        typename std::remove_reference<deleter_type>::type&&,
        typename std::enable_if<std::is_convertible<_Up*, 
            pointer>::value>::type* = 0); //= delete;
    
    template <class _Up> explicit unique_ptr(_Up*,
      typename std::enable_if<std::is_convertible<_Up*, 
          pointer>::value>::type* = 0); //= delete;
    
    //disable reset with convertible pointer types (N2315 - 20.6.5.3.3) 
      template <class _Up>
        typename std::enable_if<std::is_convertible<_Up*,
            pointer>::value>::type reset(_Up*); //= delete;
            
    private:
      __tuple_type _M_t;
  };
  
  template<class _Tp, class _Tp_Deleter> 
    inline void swap(unique_ptr<_Tp, _Tp_Deleter>& x, 
        unique_ptr<_Tp, _Tp_Deleter>& y) 
    { x.swap(y); }

  template<class _Tp, class _Tp_Deleter> 
    inline void swap(unique_ptr<_Tp, _Tp_Deleter>&& x, 
        unique_ptr<_Tp, _Tp_Deleter>& y)
    { x.swap(y); }

  template<class _Tp, class _Tp_Deleter> 
    inline void swap(unique_ptr<_Tp, _Tp_Deleter>& x, 
        unique_ptr<_Tp, _Tp_Deleter>&& y)
    { x.swap(y); }
  
  template<class _Tp, class _Tp_Deleter, class _Up, class _Up_Deleter>
    inline bool operator==(const unique_ptr<_Tp, _Tp_Deleter>& x, 
        const unique_ptr<_Up, _Up_Deleter>& y)
    { return x.get() == y.get(); }

  template<class _Tp, class _Tp_Deleter, class _Up, class _Up_Deleter>
    inline bool operator!=(const unique_ptr<_Tp, _Tp_Deleter>& x, 
        const unique_ptr<_Up, _Up_Deleter>& y)
    { return !(x.get() == y.get()); }

  template<class _Tp, class _Tp_Deleter, class _Up, class _Up_Deleter>
    inline bool operator<(const unique_ptr<_Tp, _Tp_Deleter>& x, 
        const unique_ptr<_Up, _Up_Deleter>& y)
    { return x.get() < y.get(); }

  template<class _Tp, class _Tp_Deleter, class _Up, class _Up_Deleter>
    inline bool operator<=(const unique_ptr<_Tp, _Tp_Deleter>& x, 
        const unique_ptr<_Up, _Up_Deleter>& y)
    { return !(y.get() < x.get()); }

  template<class _Tp, class _Tp_Deleter, class _Up, class _Up_Deleter>
    inline bool operator>(const unique_ptr<_Tp, _Tp_Deleter>& x, 
        const unique_ptr<_Up, _Up_Deleter>& y)
    { return y.get() < x.get(); }

  template<class _Tp, class _Tp_Deleter, class _Up, class _Up_Deleter>
    inline bool operator>=(const unique_ptr<_Tp, _Tp_Deleter>& x, 
        const unique_ptr<_Up, _Up_Deleter>& y)
    { return !(x.get() < y.get()); }

}

#endif /* _STL_UNIQUE_PTR_H */