// hashtable.h header -*- C++ -*-
// Copyright (C) 2007, 2008, 2009, 2010 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
// .
/** @file bits/hashtable.h
* This is an internal header file, included by other library headers.
* You should not attempt to use it directly.
* @headername{unordered_map, unordered_set}
*/
#ifndef _HASHTABLE_H
#define _HASHTABLE_H 1
#pragma GCC system_header
#include
namespace std
{
// Class template _Hashtable, class definition.
// Meaning of class template _Hashtable's template parameters
// _Key and _Value: arbitrary CopyConstructible types.
// _Allocator: an allocator type ([lib.allocator.requirements]) whose
// value type is Value. As a conforming extension, we allow for
// value type != Value.
// _ExtractKey: function object that takes a object of type Value
// and returns a value of type _Key.
// _Equal: function object that takes two objects of type k and returns
// a bool-like value that is true if the two objects are considered equal.
// _H1: the hash function. A unary function object with argument type
// Key and result type size_t. Return values should be distributed
// over the entire range [0, numeric_limits:::max()].
// _H2: the range-hashing function (in the terminology of Tavori and
// Dreizin). A binary function object whose argument types and result
// type are all size_t. Given arguments r and N, the return value is
// in the range [0, N).
// _Hash: the ranged hash function (Tavori and Dreizin). A binary function
// whose argument types are _Key and size_t and whose result type is
// size_t. Given arguments k and N, the return value is in the range
// [0, N). Default: hash(k, N) = h2(h1(k), N). If _Hash is anything other
// than the default, _H1 and _H2 are ignored.
// _RehashPolicy: Policy class with three members, all of which govern
// the bucket count. _M_next_bkt(n) returns a bucket count no smaller
// than n. _M_bkt_for_elements(n) returns a bucket count appropriate
// for an element count of n. _M_need_rehash(n_bkt, n_elt, n_ins)
// determines whether, if the current bucket count is n_bkt and the
// current element count is n_elt, we need to increase the bucket
// count. If so, returns make_pair(true, n), where n is the new
// bucket count. If not, returns make_pair(false, ).
// ??? Right now it is hard-wired that the number of buckets never
// shrinks. Should we allow _RehashPolicy to change that?
// __cache_hash_code: bool. true if we store the value of the hash
// function along with the value. This is a time-space tradeoff.
// Storing it may improve lookup speed by reducing the number of times
// we need to call the Equal function.
// __constant_iterators: bool. true if iterator and const_iterator are
// both constant iterator types. This is true for unordered_set and
// unordered_multiset, false for unordered_map and unordered_multimap.
// __unique_keys: bool. true if the return value of _Hashtable::count(k)
// is always at most one, false if it may be an arbitrary number. This
// true for unordered_set and unordered_map, false for unordered_multiset
// and unordered_multimap.
template
class _Hashtable
: public __detail::_Rehash_base<_RehashPolicy,
_Hashtable<_Key, _Value, _Allocator,
_ExtractKey,
_Equal, _H1, _H2, _Hash,
_RehashPolicy,
__cache_hash_code,
__constant_iterators,
__unique_keys> >,
public __detail::_Hash_code_base<_Key, _Value, _ExtractKey, _Equal,
_H1, _H2, _Hash, __cache_hash_code>,
public __detail::_Map_base<_Key, _Value, _ExtractKey, __unique_keys,
_Hashtable<_Key, _Value, _Allocator,
_ExtractKey,
_Equal, _H1, _H2, _Hash,
_RehashPolicy,
__cache_hash_code,
__constant_iterators,
__unique_keys> >,
public __detail::_Equality_base<_ExtractKey, __unique_keys,
_Hashtable<_Key, _Value, _Allocator,
_ExtractKey,
_Equal, _H1, _H2, _Hash,
_RehashPolicy,
__cache_hash_code,
__constant_iterators,
__unique_keys> >
{
public:
typedef _Allocator allocator_type;
typedef _Value value_type;
typedef _Key key_type;
typedef _Equal key_equal;
// mapped_type, if present, comes from _Map_base.
// hasher, if present, comes from _Hash_code_base.
typedef typename _Allocator::pointer pointer;
typedef typename _Allocator::const_pointer const_pointer;
typedef typename _Allocator::reference reference;
typedef typename _Allocator::const_reference const_reference;
typedef std::size_t size_type;
typedef std::ptrdiff_t difference_type;
typedef __detail::_Node_iterator
local_iterator;
typedef __detail::_Node_const_iterator
const_local_iterator;
typedef __detail::_Hashtable_iterator
iterator;
typedef __detail::_Hashtable_const_iterator
const_iterator;
template
friend struct __detail::_Map_base;
private:
typedef __detail::_Hash_node<_Value, __cache_hash_code> _Node;
typedef typename _Allocator::template rebind<_Node>::other
_Node_allocator_type;
typedef typename _Allocator::template rebind<_Node*>::other
_Bucket_allocator_type;
typedef typename _Allocator::template rebind<_Value>::other
_Value_allocator_type;
_Node_allocator_type _M_node_allocator;
_Node** _M_buckets;
size_type _M_bucket_count;
size_type _M_begin_bucket_index; // First non-empty bucket.
size_type _M_element_count;
_RehashPolicy _M_rehash_policy;
template
_Node*
_M_allocate_node(_Args&&... __args);
void
_M_deallocate_node(_Node* __n);
void
_M_deallocate_nodes(_Node**, size_type);
_Node**
_M_allocate_buckets(size_type __n);
void
_M_deallocate_buckets(_Node**, size_type __n);
public:
// Constructor, destructor, assignment, swap
_Hashtable(size_type __bucket_hint,
const _H1&, const _H2&, const _Hash&,
const _Equal&, const _ExtractKey&,
const allocator_type&);
template
_Hashtable(_InputIterator __first, _InputIterator __last,
size_type __bucket_hint,
const _H1&, const _H2&, const _Hash&,
const _Equal&, const _ExtractKey&,
const allocator_type&);
_Hashtable(const _Hashtable&);
_Hashtable(_Hashtable&&);
_Hashtable&
operator=(const _Hashtable& __ht)
{
_Hashtable __tmp(__ht);
this->swap(__tmp);
return *this;
}
_Hashtable&
operator=(_Hashtable&& __ht)
{
// NB: DR 1204.
// NB: DR 675.
this->clear();
this->swap(__ht);
return *this;
}
~_Hashtable();
void swap(_Hashtable&);
// Basic container operations
iterator
begin()
{ return iterator(_M_buckets + _M_begin_bucket_index); }
const_iterator
begin() const
{ return const_iterator(_M_buckets + _M_begin_bucket_index); }
iterator
end()
{ return iterator(_M_buckets + _M_bucket_count); }
const_iterator
end() const
{ return const_iterator(_M_buckets + _M_bucket_count); }
const_iterator
cbegin() const
{ return const_iterator(_M_buckets + _M_begin_bucket_index); }
const_iterator
cend() const
{ return const_iterator(_M_buckets + _M_bucket_count); }
size_type
size() const
{ return _M_element_count; }
bool
empty() const
{ return size() == 0; }
allocator_type
get_allocator() const
{ return allocator_type(_M_node_allocator); }
size_type
max_size() const
{ return _M_node_allocator.max_size(); }
// Observers
key_equal
key_eq() const
{ return this->_M_eq; }
// hash_function, if present, comes from _Hash_code_base.
// Bucket operations
size_type
bucket_count() const
{ return _M_bucket_count; }
size_type
max_bucket_count() const
{ return max_size(); }
size_type
bucket_size(size_type __n) const
{ return std::distance(begin(__n), end(__n)); }
size_type
bucket(const key_type& __k) const
{
return this->_M_bucket_index(__k, this->_M_hash_code(__k),
bucket_count());
}
local_iterator
begin(size_type __n)
{ return local_iterator(_M_buckets[__n]); }
local_iterator
end(size_type)
{ return local_iterator(0); }
const_local_iterator
begin(size_type __n) const
{ return const_local_iterator(_M_buckets[__n]); }
const_local_iterator
end(size_type) const
{ return const_local_iterator(0); }
// DR 691.
const_local_iterator
cbegin(size_type __n) const
{ return const_local_iterator(_M_buckets[__n]); }
const_local_iterator
cend(size_type) const
{ return const_local_iterator(0); }
float
load_factor() const
{
return static_cast(size()) / static_cast(bucket_count());
}
// max_load_factor, if present, comes from _Rehash_base.
// Generalization of max_load_factor. Extension, not found in TR1. Only
// useful if _RehashPolicy is something other than the default.
const _RehashPolicy&
__rehash_policy() const
{ return _M_rehash_policy; }
void
__rehash_policy(const _RehashPolicy&);
// Lookup.
iterator
find(const key_type& __k);
const_iterator
find(const key_type& __k) const;
size_type
count(const key_type& __k) const;
std::pair
equal_range(const key_type& __k);
std::pair
equal_range(const key_type& __k) const;
private:
// Find and insert helper functions and types
_Node*
_M_find_node(_Node*, const key_type&,
typename _Hashtable::_Hash_code_type) const;
template
iterator
_M_insert_bucket(_Arg&&, size_type,
typename _Hashtable::_Hash_code_type);
template
std::pair
_M_insert(_Arg&&, std::true_type);
template
iterator
_M_insert(_Arg&&, std::false_type);
typedef typename std::conditional<__unique_keys,
std::pair,
iterator>::type
_Insert_Return_Type;
typedef typename std::conditional<__unique_keys,
std::_Select1st<_Insert_Return_Type>,
std::_Identity<_Insert_Return_Type>
>::type
_Insert_Conv_Type;
public:
// Insert and erase
_Insert_Return_Type
insert(const value_type& __v)
{ return _M_insert(__v, std::integral_constant()); }
iterator
insert(const_iterator, const value_type& __v)
{ return _Insert_Conv_Type()(insert(__v)); }
_Insert_Return_Type
insert(value_type&& __v)
{ return _M_insert(std::move(__v),
std::integral_constant()); }
iterator
insert(const_iterator, value_type&& __v)
{ return _Insert_Conv_Type()(insert(std::move(__v))); }
template::value>::type>
_Insert_Return_Type
insert(_Pair&& __v)
{ return _M_insert(std::forward<_Pair>(__v),
std::integral_constant()); }
template::value>::type>
iterator
insert(const_iterator, _Pair&& __v)
{ return _Insert_Conv_Type()(insert(std::forward<_Pair>(__v))); }
template
void
insert(_InputIterator __first, _InputIterator __last);
void
insert(initializer_list __l)
{ this->insert(__l.begin(), __l.end()); }
iterator
erase(const_iterator);
size_type
erase(const key_type&);
iterator
erase(const_iterator, const_iterator);
void
clear();
// Set number of buckets to be appropriate for container of n element.
void rehash(size_type __n);
// DR 1189.
// reserve, if present, comes from _Rehash_base.
private:
// Unconditionally change size of bucket array to n.
void _M_rehash(size_type __n);
};
// Definitions of class template _Hashtable's out-of-line member functions.
template
template
typename _Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::_Node*
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_M_allocate_node(_Args&&... __args)
{
_Node* __n = _M_node_allocator.allocate(1);
__try
{
_M_node_allocator.construct(__n, std::forward<_Args>(__args)...);
__n->_M_next = 0;
return __n;
}
__catch(...)
{
_M_node_allocator.deallocate(__n, 1);
__throw_exception_again;
}
}
template
void
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_M_deallocate_node(_Node* __n)
{
_M_node_allocator.destroy(__n);
_M_node_allocator.deallocate(__n, 1);
}
template
void
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_M_deallocate_nodes(_Node** __array, size_type __n)
{
for (size_type __i = 0; __i < __n; ++__i)
{
_Node* __p = __array[__i];
while (__p)
{
_Node* __tmp = __p;
__p = __p->_M_next;
_M_deallocate_node(__tmp);
}
__array[__i] = 0;
}
}
template
typename _Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::_Node**
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_M_allocate_buckets(size_type __n)
{
_Bucket_allocator_type __alloc(_M_node_allocator);
// We allocate one extra bucket to hold a sentinel, an arbitrary
// non-null pointer. Iterator increment relies on this.
_Node** __p = __alloc.allocate(__n + 1);
std::fill(__p, __p + __n, (_Node*) 0);
__p[__n] = reinterpret_cast<_Node*>(0x1000);
return __p;
}
template
void
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_M_deallocate_buckets(_Node** __p, size_type __n)
{
_Bucket_allocator_type __alloc(_M_node_allocator);
__alloc.deallocate(__p, __n + 1);
}
template
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_Hashtable(size_type __bucket_hint,
const _H1& __h1, const _H2& __h2, const _Hash& __h,
const _Equal& __eq, const _ExtractKey& __exk,
const allocator_type& __a)
: __detail::_Rehash_base<_RehashPolicy, _Hashtable>(),
__detail::_Hash_code_base<_Key, _Value, _ExtractKey, _Equal,
_H1, _H2, _Hash, __chc>(__exk, __eq,
__h1, __h2, __h),
__detail::_Map_base<_Key, _Value, _ExtractKey, __uk, _Hashtable>(),
_M_node_allocator(__a),
_M_bucket_count(0),
_M_element_count(0),
_M_rehash_policy()
{
_M_bucket_count = _M_rehash_policy._M_next_bkt(__bucket_hint);
_M_buckets = _M_allocate_buckets(_M_bucket_count);
_M_begin_bucket_index = _M_bucket_count;
}
template
template
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_Hashtable(_InputIterator __f, _InputIterator __l,
size_type __bucket_hint,
const _H1& __h1, const _H2& __h2, const _Hash& __h,
const _Equal& __eq, const _ExtractKey& __exk,
const allocator_type& __a)
: __detail::_Rehash_base<_RehashPolicy, _Hashtable>(),
__detail::_Hash_code_base<_Key, _Value, _ExtractKey, _Equal,
_H1, _H2, _Hash, __chc>(__exk, __eq,
__h1, __h2, __h),
__detail::_Map_base<_Key, _Value, _ExtractKey, __uk, _Hashtable>(),
_M_node_allocator(__a),
_M_bucket_count(0),
_M_element_count(0),
_M_rehash_policy()
{
_M_bucket_count = std::max(_M_rehash_policy._M_next_bkt(__bucket_hint),
_M_rehash_policy.
_M_bkt_for_elements(__detail::
__distance_fw(__f,
__l)));
_M_buckets = _M_allocate_buckets(_M_bucket_count);
_M_begin_bucket_index = _M_bucket_count;
__try
{
for (; __f != __l; ++__f)
this->insert(*__f);
}
__catch(...)
{
clear();
_M_deallocate_buckets(_M_buckets, _M_bucket_count);
__throw_exception_again;
}
}
template
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_Hashtable(const _Hashtable& __ht)
: __detail::_Rehash_base<_RehashPolicy, _Hashtable>(__ht),
__detail::_Hash_code_base<_Key, _Value, _ExtractKey, _Equal,
_H1, _H2, _Hash, __chc>(__ht),
__detail::_Map_base<_Key, _Value, _ExtractKey, __uk, _Hashtable>(__ht),
_M_node_allocator(__ht._M_node_allocator),
_M_bucket_count(__ht._M_bucket_count),
_M_begin_bucket_index(__ht._M_begin_bucket_index),
_M_element_count(__ht._M_element_count),
_M_rehash_policy(__ht._M_rehash_policy)
{
_M_buckets = _M_allocate_buckets(_M_bucket_count);
__try
{
for (size_type __i = 0; __i < __ht._M_bucket_count; ++__i)
{
_Node* __n = __ht._M_buckets[__i];
_Node** __tail = _M_buckets + __i;
while (__n)
{
*__tail = _M_allocate_node(__n->_M_v);
this->_M_copy_code(*__tail, __n);
__tail = &((*__tail)->_M_next);
__n = __n->_M_next;
}
}
}
__catch(...)
{
clear();
_M_deallocate_buckets(_M_buckets, _M_bucket_count);
__throw_exception_again;
}
}
template
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_Hashtable(_Hashtable&& __ht)
: __detail::_Rehash_base<_RehashPolicy, _Hashtable>(__ht),
__detail::_Hash_code_base<_Key, _Value, _ExtractKey, _Equal,
_H1, _H2, _Hash, __chc>(__ht),
__detail::_Map_base<_Key, _Value, _ExtractKey, __uk, _Hashtable>(__ht),
_M_node_allocator(__ht._M_node_allocator),
_M_buckets(__ht._M_buckets),
_M_bucket_count(__ht._M_bucket_count),
_M_begin_bucket_index(__ht._M_begin_bucket_index),
_M_element_count(__ht._M_element_count),
_M_rehash_policy(__ht._M_rehash_policy)
{
size_type __n_bkt = __ht._M_rehash_policy._M_next_bkt(0);
__ht._M_buckets = __ht._M_allocate_buckets(__n_bkt);
__ht._M_bucket_count = __n_bkt;
__ht._M_begin_bucket_index = __ht._M_bucket_count;
__ht._M_element_count = 0;
__ht._M_rehash_policy = _RehashPolicy();
}
template
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
~_Hashtable()
{
clear();
_M_deallocate_buckets(_M_buckets, _M_bucket_count);
}
template
void
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
swap(_Hashtable& __x)
{
// The only base class with member variables is hash_code_base. We
// define _Hash_code_base::_M_swap because different specializations
// have different members.
__detail::_Hash_code_base<_Key, _Value, _ExtractKey, _Equal,
_H1, _H2, _Hash, __chc>::_M_swap(__x);
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 431. Swapping containers with unequal allocators.
std::__alloc_swap<_Node_allocator_type>::_S_do_it(_M_node_allocator,
__x._M_node_allocator);
std::swap(_M_rehash_policy, __x._M_rehash_policy);
std::swap(_M_buckets, __x._M_buckets);
std::swap(_M_bucket_count, __x._M_bucket_count);
std::swap(_M_begin_bucket_index, __x._M_begin_bucket_index);
std::swap(_M_element_count, __x._M_element_count);
}
template
void
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
__rehash_policy(const _RehashPolicy& __pol)
{
_M_rehash_policy = __pol;
size_type __n_bkt = __pol._M_bkt_for_elements(_M_element_count);
if (__n_bkt > _M_bucket_count)
_M_rehash(__n_bkt);
}
template
typename _Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::iterator
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
find(const key_type& __k)
{
typename _Hashtable::_Hash_code_type __code = this->_M_hash_code(__k);
std::size_t __n = this->_M_bucket_index(__k, __code, _M_bucket_count);
_Node* __p = _M_find_node(_M_buckets[__n], __k, __code);
return __p ? iterator(__p, _M_buckets + __n) : this->end();
}
template
typename _Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::const_iterator
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
find(const key_type& __k) const
{
typename _Hashtable::_Hash_code_type __code = this->_M_hash_code(__k);
std::size_t __n = this->_M_bucket_index(__k, __code, _M_bucket_count);
_Node* __p = _M_find_node(_M_buckets[__n], __k, __code);
return __p ? const_iterator(__p, _M_buckets + __n) : this->end();
}
template
typename _Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::size_type
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
count(const key_type& __k) const
{
typename _Hashtable::_Hash_code_type __code = this->_M_hash_code(__k);
std::size_t __n = this->_M_bucket_index(__k, __code, _M_bucket_count);
std::size_t __result = 0;
for (_Node* __p = _M_buckets[__n]; __p; __p = __p->_M_next)
if (this->_M_compare(__k, __code, __p))
++__result;
return __result;
}
template
std::pair::iterator,
typename _Hashtable<_Key, _Value, _Allocator,
_ExtractKey, _Equal, _H1,
_H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::iterator>
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
equal_range(const key_type& __k)
{
typename _Hashtable::_Hash_code_type __code = this->_M_hash_code(__k);
std::size_t __n = this->_M_bucket_index(__k, __code, _M_bucket_count);
_Node** __head = _M_buckets + __n;
_Node* __p = _M_find_node(*__head, __k, __code);
if (__p)
{
_Node* __p1 = __p->_M_next;
for (; __p1; __p1 = __p1->_M_next)
if (!this->_M_compare(__k, __code, __p1))
break;
iterator __first(__p, __head);
iterator __last(__p1, __head);
if (!__p1)
__last._M_incr_bucket();
return std::make_pair(__first, __last);
}
else
return std::make_pair(this->end(), this->end());
}
template
std::pair::const_iterator,
typename _Hashtable<_Key, _Value, _Allocator,
_ExtractKey, _Equal, _H1,
_H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::const_iterator>
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
equal_range(const key_type& __k) const
{
typename _Hashtable::_Hash_code_type __code = this->_M_hash_code(__k);
std::size_t __n = this->_M_bucket_index(__k, __code, _M_bucket_count);
_Node** __head = _M_buckets + __n;
_Node* __p = _M_find_node(*__head, __k, __code);
if (__p)
{
_Node* __p1 = __p->_M_next;
for (; __p1; __p1 = __p1->_M_next)
if (!this->_M_compare(__k, __code, __p1))
break;
const_iterator __first(__p, __head);
const_iterator __last(__p1, __head);
if (!__p1)
__last._M_incr_bucket();
return std::make_pair(__first, __last);
}
else
return std::make_pair(this->end(), this->end());
}
// Find the node whose key compares equal to k, beginning the search
// at p (usually the head of a bucket). Return nil if no node is found.
template
typename _Hashtable<_Key, _Value, _Allocator, _ExtractKey,
_Equal, _H1, _H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::_Node*
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_M_find_node(_Node* __p, const key_type& __k,
typename _Hashtable::_Hash_code_type __code) const
{
for (; __p; __p = __p->_M_next)
if (this->_M_compare(__k, __code, __p))
return __p;
return false;
}
// Insert v in bucket n (assumes no element with its key already present).
template
template
typename _Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::iterator
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_M_insert_bucket(_Arg&& __v, size_type __n,
typename _Hashtable::_Hash_code_type __code)
{
std::pair __do_rehash
= _M_rehash_policy._M_need_rehash(_M_bucket_count,
_M_element_count, 1);
if (__do_rehash.first)
{
const key_type& __k = this->_M_extract(__v);
__n = this->_M_bucket_index(__k, __code, __do_rehash.second);
}
// Allocate the new node before doing the rehash so that we don't
// do a rehash if the allocation throws.
_Node* __new_node = _M_allocate_node(std::forward<_Arg>(__v));
__try
{
if (__do_rehash.first)
_M_rehash(__do_rehash.second);
__new_node->_M_next = _M_buckets[__n];
this->_M_store_code(__new_node, __code);
_M_buckets[__n] = __new_node;
++_M_element_count;
if (__n < _M_begin_bucket_index)
_M_begin_bucket_index = __n;
return iterator(__new_node, _M_buckets + __n);
}
__catch(...)
{
_M_deallocate_node(__new_node);
__throw_exception_again;
}
}
// Insert v if no element with its key is already present.
template
template
std::pair::iterator, bool>
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_M_insert(_Arg&& __v, std::true_type)
{
const key_type& __k = this->_M_extract(__v);
typename _Hashtable::_Hash_code_type __code = this->_M_hash_code(__k);
size_type __n = this->_M_bucket_index(__k, __code, _M_bucket_count);
if (_Node* __p = _M_find_node(_M_buckets[__n], __k, __code))
return std::make_pair(iterator(__p, _M_buckets + __n), false);
return std::make_pair(_M_insert_bucket(std::forward<_Arg>(__v),
__n, __code), true);
}
// Insert v unconditionally.
template
template
typename _Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::iterator
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_M_insert(_Arg&& __v, std::false_type)
{
std::pair __do_rehash
= _M_rehash_policy._M_need_rehash(_M_bucket_count,
_M_element_count, 1);
if (__do_rehash.first)
_M_rehash(__do_rehash.second);
const key_type& __k = this->_M_extract(__v);
typename _Hashtable::_Hash_code_type __code = this->_M_hash_code(__k);
size_type __n = this->_M_bucket_index(__k, __code, _M_bucket_count);
// First find the node, avoid leaking new_node if compare throws.
_Node* __prev = _M_find_node(_M_buckets[__n], __k, __code);
_Node* __new_node = _M_allocate_node(std::forward<_Arg>(__v));
if (__prev)
{
__new_node->_M_next = __prev->_M_next;
__prev->_M_next = __new_node;
}
else
{
__new_node->_M_next = _M_buckets[__n];
_M_buckets[__n] = __new_node;
if (__n < _M_begin_bucket_index)
_M_begin_bucket_index = __n;
}
this->_M_store_code(__new_node, __code);
++_M_element_count;
return iterator(__new_node, _M_buckets + __n);
}
template
template
void
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
insert(_InputIterator __first, _InputIterator __last)
{
size_type __n_elt = __detail::__distance_fw(__first, __last);
std::pair __do_rehash
= _M_rehash_policy._M_need_rehash(_M_bucket_count,
_M_element_count, __n_elt);
if (__do_rehash.first)
_M_rehash(__do_rehash.second);
for (; __first != __last; ++__first)
this->insert(*__first);
}
template
typename _Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::iterator
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
erase(const_iterator __it)
{
iterator __result(__it._M_cur_node, __it._M_cur_bucket);
++__result;
_Node* __cur = *__it._M_cur_bucket;
if (__cur == __it._M_cur_node)
{
*__it._M_cur_bucket = __cur->_M_next;
// If _M_begin_bucket_index no longer indexes the first non-empty
// bucket - its single node is being erased - update it.
if (!_M_buckets[_M_begin_bucket_index])
_M_begin_bucket_index = __result._M_cur_bucket - _M_buckets;
}
else
{
_Node* __next = __cur->_M_next;
while (__next != __it._M_cur_node)
{
__cur = __next;
__next = __cur->_M_next;
}
__cur->_M_next = __next->_M_next;
}
_M_deallocate_node(__it._M_cur_node);
--_M_element_count;
return __result;
}
template
typename _Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::size_type
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
erase(const key_type& __k)
{
typename _Hashtable::_Hash_code_type __code = this->_M_hash_code(__k);
std::size_t __n = this->_M_bucket_index(__k, __code, _M_bucket_count);
size_type __result = 0;
_Node** __slot = _M_buckets + __n;
while (*__slot && !this->_M_compare(__k, __code, *__slot))
__slot = &((*__slot)->_M_next);
_Node** __saved_slot = 0;
while (*__slot && this->_M_compare(__k, __code, *__slot))
{
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 526. Is it undefined if a function in the standard changes
// in parameters?
if (std::__addressof(this->_M_extract((*__slot)->_M_v))
!= std::__addressof(__k))
{
_Node* __p = *__slot;
*__slot = __p->_M_next;
_M_deallocate_node(__p);
--_M_element_count;
++__result;
}
else
{
__saved_slot = __slot;
__slot = &((*__slot)->_M_next);
}
}
if (__saved_slot)
{
_Node* __p = *__saved_slot;
*__saved_slot = __p->_M_next;
_M_deallocate_node(__p);
--_M_element_count;
++__result;
}
// If the entire bucket indexed by _M_begin_bucket_index has been
// erased look forward for the first non-empty bucket.
if (!_M_buckets[_M_begin_bucket_index])
{
if (!_M_element_count)
_M_begin_bucket_index = _M_bucket_count;
else
{
++_M_begin_bucket_index;
while (!_M_buckets[_M_begin_bucket_index])
++_M_begin_bucket_index;
}
}
return __result;
}
// ??? This could be optimized by taking advantage of the bucket
// structure, but it's not clear that it's worth doing. It probably
// wouldn't even be an optimization unless the load factor is large.
template
typename _Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::iterator
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
erase(const_iterator __first, const_iterator __last)
{
while (__first != __last)
__first = this->erase(__first);
return iterator(__last._M_cur_node, __last._M_cur_bucket);
}
template
void
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
clear()
{
_M_deallocate_nodes(_M_buckets, _M_bucket_count);
_M_element_count = 0;
_M_begin_bucket_index = _M_bucket_count;
}
template
void
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
rehash(size_type __n)
{
_M_rehash(std::max(_M_rehash_policy._M_next_bkt(__n),
_M_rehash_policy._M_bkt_for_elements(_M_element_count
+ 1)));
}
template
void
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_M_rehash(size_type __n)
{
_Node** __new_array = _M_allocate_buckets(__n);
__try
{
_M_begin_bucket_index = __n;
for (size_type __i = 0; __i < _M_bucket_count; ++__i)
while (_Node* __p = _M_buckets[__i])
{
std::size_t __new_index = this->_M_bucket_index(__p, __n);
_M_buckets[__i] = __p->_M_next;
__p->_M_next = __new_array[__new_index];
__new_array[__new_index] = __p;
if (__new_index < _M_begin_bucket_index)
_M_begin_bucket_index = __new_index;
}
_M_deallocate_buckets(_M_buckets, _M_bucket_count);
_M_bucket_count = __n;
_M_buckets = __new_array;
}
__catch(...)
{
// A failure here means that a hash function threw an exception.
// We can't restore the previous state without calling the hash
// function again, so the only sensible recovery is to delete
// everything.
_M_deallocate_nodes(__new_array, __n);
_M_deallocate_buckets(__new_array, __n);
_M_deallocate_nodes(_M_buckets, _M_bucket_count);
_M_element_count = 0;
_M_begin_bucket_index = _M_bucket_count;
__throw_exception_again;
}
}
}
#endif // _HASHTABLE_H