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// Safe iterator implementation -*- C++ -*-
// Copyright (C) 2003-2018 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/>.
/** @file debug/safe_iterator.h
* This file is a GNU debug extension to the Standard C++ Library.
*/
#ifndef _GLIBCXX_DEBUG_SAFE_ITERATOR_H
#define _GLIBCXX_DEBUG_SAFE_ITERATOR_H 1
#include <debug/assertions.h>
#include <debug/macros.h>
#include <debug/functions.h>
#include <debug/safe_base.h>
#include <bits/stl_pair.h>
#include <ext/type_traits.h>
namespace __gnu_debug
{
/** Helper struct to deal with sequence offering a before_begin
* iterator.
**/
template<typename _Sequence>
struct _BeforeBeginHelper
{
template<typename _Iterator>
static bool
_S_Is(const _Safe_iterator<_Iterator, _Sequence>&)
{ return false; }
template<typename _Iterator>
static bool
_S_Is_Beginnest(const _Safe_iterator<_Iterator, _Sequence>& __it)
{ return __it.base() == __it._M_get_sequence()->_M_base().begin(); }
};
/** Sequence traits giving the size of a container if possible. */
template<typename _Sequence>
struct _Sequence_traits
{
typedef _Distance_traits<typename _Sequence::iterator> _DistTraits;
static typename _DistTraits::__type
_S_size(const _Sequence& __seq)
{ return std::make_pair(__seq.size(), __dp_exact); }
};
/** \brief Safe iterator wrapper.
*
* The class template %_Safe_iterator is a wrapper around an
* iterator that tracks the iterator's movement among sequences and
* checks that operations performed on the "safe" iterator are
* legal. In additional to the basic iterator operations (which are
* validated, and then passed to the underlying iterator),
* %_Safe_iterator has member functions for iterator invalidation,
* attaching/detaching the iterator from sequences, and querying
* the iterator's state.
*
* Note that _Iterator must be the first base class so that it gets
* initialized before the iterator is being attached to the container's list
* of iterators and it is being detached before _Iterator get
* destroyed. Otherwise it would result in a data race.
*/
template<typename _Iterator, typename _Sequence>
class _Safe_iterator
: private _Iterator,
public _Safe_iterator_base
{
typedef _Iterator _Iter_base;
typedef _Safe_iterator_base _Safe_base;
typedef typename _Sequence::const_iterator _Const_iterator;
/// Determine if this is a constant iterator.
bool
_M_constant() const
{ return std::__are_same<_Const_iterator, _Safe_iterator>::__value; }
typedef std::iterator_traits<_Iterator> _Traits;
struct _Attach_single
{ };
_Safe_iterator(const _Iterator& __i, _Safe_sequence_base* __seq,
_Attach_single)
_GLIBCXX_NOEXCEPT
: _Iter_base(__i)
{ _M_attach_single(__seq); }
public:
typedef _Iterator iterator_type;
typedef typename _Traits::iterator_category iterator_category;
typedef typename _Traits::value_type value_type;
typedef typename _Traits::difference_type difference_type;
typedef typename _Traits::reference reference;
typedef typename _Traits::pointer pointer;
/// @post the iterator is singular and unattached
_Safe_iterator() _GLIBCXX_NOEXCEPT : _Iter_base() { }
/**
* @brief Safe iterator construction from an unsafe iterator and
* its sequence.
*
* @pre @p seq is not NULL
* @post this is not singular
*/
_Safe_iterator(const _Iterator& __i, const _Safe_sequence_base* __seq)
_GLIBCXX_NOEXCEPT
: _Iter_base(__i), _Safe_base(__seq, _M_constant())
{
_GLIBCXX_DEBUG_VERIFY(!this->_M_singular(),
_M_message(__msg_init_singular)
._M_iterator(*this, "this"));
}
/**
* @brief Copy construction.
*/
_Safe_iterator(const _Safe_iterator& __x) _GLIBCXX_NOEXCEPT
: _Iter_base(__x.base())
{
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// DR 408. Is vector<reverse_iterator<char*> > forbidden?
_GLIBCXX_DEBUG_VERIFY(!__x._M_singular()
|| __x.base() == _Iterator(),
_M_message(__msg_init_copy_singular)
._M_iterator(*this, "this")
._M_iterator(__x, "other"));
_M_attach(__x._M_sequence);
}
#if __cplusplus >= 201103L
/**
* @brief Move construction.
* @post __x is singular and unattached
*/
_Safe_iterator(_Safe_iterator&& __x) noexcept
: _Iter_base()
{
_GLIBCXX_DEBUG_VERIFY(!__x._M_singular()
|| __x.base() == _Iterator(),
_M_message(__msg_init_copy_singular)
._M_iterator(*this, "this")
._M_iterator(__x, "other"));
_Safe_sequence_base* __seq = __x._M_sequence;
__x._M_detach();
std::swap(base(), __x.base());
_M_attach(__seq);
}
#endif
/**
* @brief Converting constructor from a mutable iterator to a
* constant iterator.
*/
template<typename _MutableIterator>
_Safe_iterator(
const _Safe_iterator<_MutableIterator,
typename __gnu_cxx::__enable_if<(std::__are_same<_MutableIterator,
typename _Sequence::iterator::iterator_type>::__value),
_Sequence>::__type>& __x) _GLIBCXX_NOEXCEPT
: _Iter_base(__x.base())
{
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// DR 408. Is vector<reverse_iterator<char*> > forbidden?
_GLIBCXX_DEBUG_VERIFY(!__x._M_singular()
|| __x.base() == _Iterator(),
_M_message(__msg_init_const_singular)
._M_iterator(*this, "this")
._M_iterator(__x, "other"));
_M_attach(__x._M_sequence);
}
/**
* @brief Copy assignment.
*/
_Safe_iterator&
operator=(const _Safe_iterator& __x) _GLIBCXX_NOEXCEPT
{
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// DR 408. Is vector<reverse_iterator<char*> > forbidden?
_GLIBCXX_DEBUG_VERIFY(!__x._M_singular()
|| __x.base() == _Iterator(),
_M_message(__msg_copy_singular)
._M_iterator(*this, "this")
._M_iterator(__x, "other"));
if (this->_M_sequence && this->_M_sequence == __x._M_sequence)
{
__gnu_cxx::__scoped_lock __l(this->_M_get_mutex());
base() = __x.base();
_M_version = __x._M_sequence->_M_version;
}
else
{
_M_detach();
base() = __x.base();
_M_attach(__x._M_sequence);
}
return *this;
}
#if __cplusplus >= 201103L
/**
* @brief Move assignment.
* @post __x is singular and unattached
*/
_Safe_iterator&
operator=(_Safe_iterator&& __x) noexcept
{
_GLIBCXX_DEBUG_VERIFY(this != &__x,
_M_message(__msg_self_move_assign)
._M_iterator(*this, "this"));
_GLIBCXX_DEBUG_VERIFY(!__x._M_singular()
|| __x.base() == _Iterator(),
_M_message(__msg_copy_singular)
._M_iterator(*this, "this")
._M_iterator(__x, "other"));
if (this->_M_sequence && this->_M_sequence == __x._M_sequence)
{
__gnu_cxx::__scoped_lock __l(this->_M_get_mutex());
base() = __x.base();
_M_version = __x._M_sequence->_M_version;
}
else
{
_M_detach();
base() = __x.base();
_M_attach(__x._M_sequence);
}
__x._M_detach();
__x.base() = _Iterator();
return *this;
}
#endif
/**
* @brief Iterator dereference.
* @pre iterator is dereferenceable
*/
reference
operator*() const _GLIBCXX_NOEXCEPT
{
_GLIBCXX_DEBUG_VERIFY(this->_M_dereferenceable(),
_M_message(__msg_bad_deref)
._M_iterator(*this, "this"));
return *base();
}
/**
* @brief Iterator dereference.
* @pre iterator is dereferenceable
*/
pointer
operator->() const _GLIBCXX_NOEXCEPT
{
_GLIBCXX_DEBUG_VERIFY(this->_M_dereferenceable(),
_M_message(__msg_bad_deref)
._M_iterator(*this, "this"));
return base().operator->();
}
// ------ Input iterator requirements ------
/**
* @brief Iterator preincrement
* @pre iterator is incrementable
*/
_Safe_iterator&
operator++() _GLIBCXX_NOEXCEPT
{
_GLIBCXX_DEBUG_VERIFY(this->_M_incrementable(),
_M_message(__msg_bad_inc)
._M_iterator(*this, "this"));
__gnu_cxx::__scoped_lock __l(this->_M_get_mutex());
++base();
return *this;
}
/**
* @brief Iterator postincrement
* @pre iterator is incrementable
*/
_Safe_iterator
operator++(int) _GLIBCXX_NOEXCEPT
{
_GLIBCXX_DEBUG_VERIFY(this->_M_incrementable(),
_M_message(__msg_bad_inc)
._M_iterator(*this, "this"));
__gnu_cxx::__scoped_lock __l(this->_M_get_mutex());
return _Safe_iterator(base()++, this->_M_sequence, _Attach_single());
}
// ------ Bidirectional iterator requirements ------
/**
* @brief Iterator predecrement
* @pre iterator is decrementable
*/
_Safe_iterator&
operator--() _GLIBCXX_NOEXCEPT
{
_GLIBCXX_DEBUG_VERIFY(this->_M_decrementable(),
_M_message(__msg_bad_dec)
._M_iterator(*this, "this"));
__gnu_cxx::__scoped_lock __l(this->_M_get_mutex());
--base();
return *this;
}
/**
* @brief Iterator postdecrement
* @pre iterator is decrementable
*/
_Safe_iterator
operator--(int) _GLIBCXX_NOEXCEPT
{
_GLIBCXX_DEBUG_VERIFY(this->_M_decrementable(),
_M_message(__msg_bad_dec)
._M_iterator(*this, "this"));
__gnu_cxx::__scoped_lock __l(this->_M_get_mutex());
return _Safe_iterator(base()--, this->_M_sequence, _Attach_single());
}
// ------ Random access iterator requirements ------
reference
operator[](const difference_type& __n) const _GLIBCXX_NOEXCEPT
{
_GLIBCXX_DEBUG_VERIFY(this->_M_can_advance(__n)
&& this->_M_can_advance(__n+1),
_M_message(__msg_iter_subscript_oob)
._M_iterator(*this)._M_integer(__n));
return base()[__n];
}
_Safe_iterator&
operator+=(const difference_type& __n) _GLIBCXX_NOEXCEPT
{
_GLIBCXX_DEBUG_VERIFY(this->_M_can_advance(__n),
_M_message(__msg_advance_oob)
._M_iterator(*this)._M_integer(__n));
__gnu_cxx::__scoped_lock __l(this->_M_get_mutex());
base() += __n;
return *this;
}
_Safe_iterator
operator+(const difference_type& __n) const _GLIBCXX_NOEXCEPT
{
_GLIBCXX_DEBUG_VERIFY(this->_M_can_advance(__n),
_M_message(__msg_advance_oob)
._M_iterator(*this)._M_integer(__n));
return _Safe_iterator(base() + __n, this->_M_sequence);
}
_Safe_iterator&
operator-=(const difference_type& __n) _GLIBCXX_NOEXCEPT
{
_GLIBCXX_DEBUG_VERIFY(this->_M_can_advance(-__n),
_M_message(__msg_retreat_oob)
._M_iterator(*this)._M_integer(__n));
__gnu_cxx::__scoped_lock __l(this->_M_get_mutex());
base() -= __n;
return *this;
}
_Safe_iterator
operator-(const difference_type& __n) const _GLIBCXX_NOEXCEPT
{
_GLIBCXX_DEBUG_VERIFY(this->_M_can_advance(-__n),
_M_message(__msg_retreat_oob)
._M_iterator(*this)._M_integer(__n));
return _Safe_iterator(base() - __n, this->_M_sequence);
}
// ------ Utilities ------
/**
* @brief Return the underlying iterator
*/
_Iterator&
base() _GLIBCXX_NOEXCEPT { return *this; }
const _Iterator&
base() const _GLIBCXX_NOEXCEPT { return *this; }
/**
* @brief Conversion to underlying non-debug iterator to allow
* better interaction with non-debug containers.
*/
operator _Iterator() const _GLIBCXX_NOEXCEPT { return *this; }
/** Attach iterator to the given sequence. */
void
_M_attach(_Safe_sequence_base* __seq)
{ _Safe_base::_M_attach(__seq, _M_constant()); }
/** Likewise, but not thread-safe. */
void
_M_attach_single(_Safe_sequence_base* __seq)
{ _Safe_base::_M_attach_single(__seq, _M_constant()); }
/// Is the iterator dereferenceable?
bool
_M_dereferenceable() const
{ return !this->_M_singular() && !_M_is_end() && !_M_is_before_begin(); }
/// Is the iterator before a dereferenceable one?
bool
_M_before_dereferenceable() const
{
if (this->_M_incrementable())
{
_Iterator __base = base();
return ++__base != _M_get_sequence()->_M_base().end();
}
return false;
}
/// Is the iterator incrementable?
bool
_M_incrementable() const
{ return !this->_M_singular() && !_M_is_end(); }
// Is the iterator decrementable?
bool
_M_decrementable() const { return !_M_singular() && !_M_is_begin(); }
// Can we advance the iterator @p __n steps (@p __n may be negative)
bool
_M_can_advance(const difference_type& __n) const;
// Is the iterator range [*this, __rhs) valid?
bool
_M_valid_range(const _Safe_iterator& __rhs,
std::pair<difference_type, _Distance_precision>& __dist,
bool __check_dereferenceable = true) const;
// The sequence this iterator references.
typename
__gnu_cxx::__conditional_type<std::__are_same<_Const_iterator,
_Safe_iterator>::__value,
const _Sequence*,
_Sequence*>::__type
_M_get_sequence() const
{ return static_cast<_Sequence*>(_M_sequence); }
/// Is this iterator equal to the sequence's begin() iterator?
bool
_M_is_begin() const
{ return base() == _M_get_sequence()->_M_base().begin(); }
/// Is this iterator equal to the sequence's end() iterator?
bool
_M_is_end() const
{ return base() == _M_get_sequence()->_M_base().end(); }
/// Is this iterator equal to the sequence's before_begin() iterator if
/// any?
bool
_M_is_before_begin() const
{ return _BeforeBeginHelper<_Sequence>::_S_Is(*this); }
/// Is this iterator equal to the sequence's before_begin() iterator if
/// any or begin() otherwise?
bool
_M_is_beginnest() const
{ return _BeforeBeginHelper<_Sequence>::_S_Is_Beginnest(*this); }
};
template<typename _IteratorL, typename _IteratorR, typename _Sequence>
inline bool
operator==(const _Safe_iterator<_IteratorL, _Sequence>& __lhs,
const _Safe_iterator<_IteratorR, _Sequence>& __rhs)
_GLIBCXX_NOEXCEPT
{
_GLIBCXX_DEBUG_VERIFY(! __lhs._M_singular() && ! __rhs._M_singular(),
_M_message(__msg_iter_compare_bad)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
_GLIBCXX_DEBUG_VERIFY(__lhs._M_can_compare(__rhs),
_M_message(__msg_compare_different)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
return __lhs.base() == __rhs.base();
}
template<typename _Iterator, typename _Sequence>
inline bool
operator==(const _Safe_iterator<_Iterator, _Sequence>& __lhs,
const _Safe_iterator<_Iterator, _Sequence>& __rhs)
_GLIBCXX_NOEXCEPT
{
_GLIBCXX_DEBUG_VERIFY(! __lhs._M_singular() && ! __rhs._M_singular(),
_M_message(__msg_iter_compare_bad)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
_GLIBCXX_DEBUG_VERIFY(__lhs._M_can_compare(__rhs),
_M_message(__msg_compare_different)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
return __lhs.base() == __rhs.base();
}
template<typename _IteratorL, typename _IteratorR, typename _Sequence>
inline bool
operator!=(const _Safe_iterator<_IteratorL, _Sequence>& __lhs,
const _Safe_iterator<_IteratorR, _Sequence>& __rhs)
_GLIBCXX_NOEXCEPT
{
_GLIBCXX_DEBUG_VERIFY(! __lhs._M_singular() && ! __rhs._M_singular(),
_M_message(__msg_iter_compare_bad)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
_GLIBCXX_DEBUG_VERIFY(__lhs._M_can_compare(__rhs),
_M_message(__msg_compare_different)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
return __lhs.base() != __rhs.base();
}
template<typename _Iterator, typename _Sequence>
inline bool
operator!=(const _Safe_iterator<_Iterator, _Sequence>& __lhs,
const _Safe_iterator<_Iterator, _Sequence>& __rhs)
_GLIBCXX_NOEXCEPT
{
_GLIBCXX_DEBUG_VERIFY(! __lhs._M_singular() && ! __rhs._M_singular(),
_M_message(__msg_iter_compare_bad)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
_GLIBCXX_DEBUG_VERIFY(__lhs._M_can_compare(__rhs),
_M_message(__msg_compare_different)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
return __lhs.base() != __rhs.base();
}
template<typename _IteratorL, typename _IteratorR, typename _Sequence>
inline bool
operator<(const _Safe_iterator<_IteratorL, _Sequence>& __lhs,
const _Safe_iterator<_IteratorR, _Sequence>& __rhs)
_GLIBCXX_NOEXCEPT
{
_GLIBCXX_DEBUG_VERIFY(! __lhs._M_singular() && ! __rhs._M_singular(),
_M_message(__msg_iter_order_bad)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
_GLIBCXX_DEBUG_VERIFY(__lhs._M_can_compare(__rhs),
_M_message(__msg_order_different)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
return __lhs.base() < __rhs.base();
}
template<typename _Iterator, typename _Sequence>
inline bool
operator<(const _Safe_iterator<_Iterator, _Sequence>& __lhs,
const _Safe_iterator<_Iterator, _Sequence>& __rhs)
_GLIBCXX_NOEXCEPT
{
_GLIBCXX_DEBUG_VERIFY(! __lhs._M_singular() && ! __rhs._M_singular(),
_M_message(__msg_iter_order_bad)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
_GLIBCXX_DEBUG_VERIFY(__lhs._M_can_compare(__rhs),
_M_message(__msg_order_different)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
return __lhs.base() < __rhs.base();
}
template<typename _IteratorL, typename _IteratorR, typename _Sequence>
inline bool
operator<=(const _Safe_iterator<_IteratorL, _Sequence>& __lhs,
const _Safe_iterator<_IteratorR, _Sequence>& __rhs)
_GLIBCXX_NOEXCEPT
{
_GLIBCXX_DEBUG_VERIFY(! __lhs._M_singular() && ! __rhs._M_singular(),
_M_message(__msg_iter_order_bad)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
_GLIBCXX_DEBUG_VERIFY(__lhs._M_can_compare(__rhs),
_M_message(__msg_order_different)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
return __lhs.base() <= __rhs.base();
}
template<typename _Iterator, typename _Sequence>
inline bool
operator<=(const _Safe_iterator<_Iterator, _Sequence>& __lhs,
const _Safe_iterator<_Iterator, _Sequence>& __rhs)
_GLIBCXX_NOEXCEPT
{
_GLIBCXX_DEBUG_VERIFY(! __lhs._M_singular() && ! __rhs._M_singular(),
_M_message(__msg_iter_order_bad)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
_GLIBCXX_DEBUG_VERIFY(__lhs._M_can_compare(__rhs),
_M_message(__msg_order_different)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
return __lhs.base() <= __rhs.base();
}
template<typename _IteratorL, typename _IteratorR, typename _Sequence>
inline bool
operator>(const _Safe_iterator<_IteratorL, _Sequence>& __lhs,
const _Safe_iterator<_IteratorR, _Sequence>& __rhs)
_GLIBCXX_NOEXCEPT
{
_GLIBCXX_DEBUG_VERIFY(! __lhs._M_singular() && ! __rhs._M_singular(),
_M_message(__msg_iter_order_bad)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
_GLIBCXX_DEBUG_VERIFY(__lhs._M_can_compare(__rhs),
_M_message(__msg_order_different)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
return __lhs.base() > __rhs.base();
}
template<typename _Iterator, typename _Sequence>
inline bool
operator>(const _Safe_iterator<_Iterator, _Sequence>& __lhs,
const _Safe_iterator<_Iterator, _Sequence>& __rhs)
_GLIBCXX_NOEXCEPT
{
_GLIBCXX_DEBUG_VERIFY(! __lhs._M_singular() && ! __rhs._M_singular(),
_M_message(__msg_iter_order_bad)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
_GLIBCXX_DEBUG_VERIFY(__lhs._M_can_compare(__rhs),
_M_message(__msg_order_different)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
return __lhs.base() > __rhs.base();
}
template<typename _IteratorL, typename _IteratorR, typename _Sequence>
inline bool
operator>=(const _Safe_iterator<_IteratorL, _Sequence>& __lhs,
const _Safe_iterator<_IteratorR, _Sequence>& __rhs)
_GLIBCXX_NOEXCEPT
{
_GLIBCXX_DEBUG_VERIFY(! __lhs._M_singular() && ! __rhs._M_singular(),
_M_message(__msg_iter_order_bad)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
_GLIBCXX_DEBUG_VERIFY(__lhs._M_can_compare(__rhs),
_M_message(__msg_order_different)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
return __lhs.base() >= __rhs.base();
}
template<typename _Iterator, typename _Sequence>
inline bool
operator>=(const _Safe_iterator<_Iterator, _Sequence>& __lhs,
const _Safe_iterator<_Iterator, _Sequence>& __rhs)
_GLIBCXX_NOEXCEPT
{
_GLIBCXX_DEBUG_VERIFY(! __lhs._M_singular() && ! __rhs._M_singular(),
_M_message(__msg_iter_order_bad)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
_GLIBCXX_DEBUG_VERIFY(__lhs._M_can_compare(__rhs),
_M_message(__msg_order_different)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
return __lhs.base() >= __rhs.base();
}
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// According to the resolution of DR179 not only the various comparison
// operators but also operator- must accept mixed iterator/const_iterator
// parameters.
template<typename _IteratorL, typename _IteratorR, typename _Sequence>
inline typename _Safe_iterator<_IteratorL, _Sequence>::difference_type
operator-(const _Safe_iterator<_IteratorL, _Sequence>& __lhs,
const _Safe_iterator<_IteratorR, _Sequence>& __rhs)
_GLIBCXX_NOEXCEPT
{
_GLIBCXX_DEBUG_VERIFY(! __lhs._M_singular() && ! __rhs._M_singular(),
_M_message(__msg_distance_bad)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
_GLIBCXX_DEBUG_VERIFY(__lhs._M_can_compare(__rhs),
_M_message(__msg_distance_different)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
return __lhs.base() - __rhs.base();
}
template<typename _Iterator, typename _Sequence>
inline typename _Safe_iterator<_Iterator, _Sequence>::difference_type
operator-(const _Safe_iterator<_Iterator, _Sequence>& __lhs,
const _Safe_iterator<_Iterator, _Sequence>& __rhs)
_GLIBCXX_NOEXCEPT
{
_GLIBCXX_DEBUG_VERIFY(! __lhs._M_singular() && ! __rhs._M_singular(),
_M_message(__msg_distance_bad)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
_GLIBCXX_DEBUG_VERIFY(__lhs._M_can_compare(__rhs),
_M_message(__msg_distance_different)
._M_iterator(__lhs, "lhs")
._M_iterator(__rhs, "rhs"));
return __lhs.base() - __rhs.base();
}
template<typename _Iterator, typename _Sequence>
inline _Safe_iterator<_Iterator, _Sequence>
operator+(typename _Safe_iterator<_Iterator,_Sequence>::difference_type __n,
const _Safe_iterator<_Iterator, _Sequence>& __i) _GLIBCXX_NOEXCEPT
{ return __i + __n; }
/** Safe iterators know if they are dereferenceable. */
template<typename _Iterator, typename _Sequence>
inline bool
__check_dereferenceable(const _Safe_iterator<_Iterator, _Sequence>& __x)
{ return __x._M_dereferenceable(); }
/** Safe iterators know how to check if they form a valid range. */
template<typename _Iterator, typename _Sequence>
inline bool
__valid_range(const _Safe_iterator<_Iterator, _Sequence>& __first,
const _Safe_iterator<_Iterator, _Sequence>& __last,
typename _Distance_traits<_Iterator>::__type& __dist)
{ return __first._M_valid_range(__last, __dist); }
/** Safe iterators can help to get better distance knowledge. */
template<typename _Iterator, typename _Sequence>
inline typename _Distance_traits<_Iterator>::__type
__get_distance(const _Safe_iterator<_Iterator, _Sequence>& __first,
const _Safe_iterator<_Iterator, _Sequence>& __last,
std::random_access_iterator_tag)
{ return std::make_pair(__last.base() - __first.base(), __dp_exact); }
template<typename _Iterator, typename _Sequence>
inline typename _Distance_traits<_Iterator>::__type
__get_distance(const _Safe_iterator<_Iterator, _Sequence>& __first,
const _Safe_iterator<_Iterator, _Sequence>& __last,
std::input_iterator_tag)
{
typedef typename _Distance_traits<_Iterator>::__type _Diff;
typedef _Sequence_traits<_Sequence> _SeqTraits;
if (__first.base() == __last.base())
return std::make_pair(0, __dp_exact);
if (__first._M_is_before_begin())
{
if (__last._M_is_begin())
return std::make_pair(1, __dp_exact);
return std::make_pair(1, __dp_sign);
}
if (__first._M_is_begin())
{
if (__last._M_is_before_begin())
return std::make_pair(-1, __dp_exact);
if (__last._M_is_end())
return _SeqTraits::_S_size(*__first._M_get_sequence());
return std::make_pair(1, __dp_sign);
}
if (__first._M_is_end())
{
if (__last._M_is_before_begin())
return std::make_pair(-1, __dp_exact);
if (__last._M_is_begin())
{
_Diff __diff = _SeqTraits::_S_size(*__first._M_get_sequence());
return std::make_pair(-__diff.first, __diff.second);
}
return std::make_pair(-1, __dp_sign);
}
if (__last._M_is_before_begin() || __last._M_is_begin())
return std::make_pair(-1, __dp_sign);
if (__last._M_is_end())
return std::make_pair(1, __dp_sign);
return std::make_pair(1, __dp_equality);
}
// Get distance from sequence begin to specified iterator.
template<typename _Iterator, typename _Sequence>
inline typename _Distance_traits<_Iterator>::__type
__get_distance_from_begin(const _Safe_iterator<_Iterator, _Sequence>& __it)
{
typedef _Sequence_traits<_Sequence> _SeqTraits;
// No need to consider before_begin as this function is only used in
// _M_can_advance which won't be used for forward_list iterators.
if (__it._M_is_begin())
return std::make_pair(0, __dp_exact);
if (__it._M_is_end())
return _SeqTraits::_S_size(*__it._M_get_sequence());
typename _Distance_traits<_Iterator>::__type __res
= __get_distance(__it._M_get_sequence()->_M_base().begin(), __it.base());
if (__res.second == __dp_equality)
return std::make_pair(1, __dp_sign);
return __res;
}
// Get distance from specified iterator to sequence end.
template<typename _Iterator, typename _Sequence>
inline typename _Distance_traits<_Iterator>::__type
__get_distance_to_end(const _Safe_iterator<_Iterator, _Sequence>& __it)
{
typedef _Sequence_traits<_Sequence> _SeqTraits;
// No need to consider before_begin as this function is only used in
// _M_can_advance which won't be used for forward_list iterators.
if (__it._M_is_begin())
return _SeqTraits::_S_size(*__it._M_get_sequence());
if (__it._M_is_end())
return std::make_pair(0, __dp_exact);
typename _Distance_traits<_Iterator>::__type __res
= __get_distance(__it.base(), __it._M_get_sequence()->_M_base().end());
if (__res.second == __dp_equality)
return std::make_pair(1, __dp_sign);
return __res;
}
#if __cplusplus < 201103L
template<typename _Iterator, typename _Sequence>
struct __is_safe_random_iterator<_Safe_iterator<_Iterator, _Sequence> >
: std::__are_same<std::random_access_iterator_tag,
typename std::iterator_traits<_Iterator>::
iterator_category>
{ };
#else
template<typename _Iterator, typename _Sequence>
_Iterator
__base(const _Safe_iterator<_Iterator, _Sequence>& __it,
std::random_access_iterator_tag)
{ return __it.base(); }
template<typename _Iterator, typename _Sequence>
const _Safe_iterator<_Iterator, _Sequence>&
__base(const _Safe_iterator<_Iterator, _Sequence>& __it,
std::input_iterator_tag)
{ return __it; }
template<typename _Iterator, typename _Sequence>
auto
__base(const _Safe_iterator<_Iterator, _Sequence>& __it)
-> decltype(__base(__it, std::__iterator_category(__it)))
{ return __base(__it, std::__iterator_category(__it)); }
#endif
#if __cplusplus < 201103L
template<typename _Iterator, typename _Sequence>
struct _Unsafe_type<_Safe_iterator<_Iterator, _Sequence> >
{ typedef _Iterator _Type; };
#endif
template<typename _Iterator, typename _Sequence>
inline _Iterator
__unsafe(const _Safe_iterator<_Iterator, _Sequence>& __it)
{ return __it.base(); }
} // namespace __gnu_debug
#include <debug/safe_iterator.tcc>
#endif
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