windows-nt/Source/XPSP1/NT/base/crts/libw32/include/xhash

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2020-09-26 03:20:57 -05:00
// xhash internal header
#pragma once
#ifndef _XHASH_
#define _XHASH_
#include <functional>
#include <list>
#include <vector>
#pragma pack(push,8)
#pragma warning(push,3)
#pragma warning(disable: 4127)
_STD_BEGIN
// TEMPLATE CLASS hash_compare
template<class _Kty,
class _Pr = less<_Kty> >
class hash_compare
{ // traits class for hash containers
public:
enum
{ // parameters for hash table
bucket_size = 4, // 0 < bucket_size
min_buckets = 8}; // min_buckets = 2 ^^ N, 0 < N
hash_compare()
: comp()
{ // construct with default comparator
}
hash_compare(_Pr _Pred)
: comp(_Pred)
{ // construct with _Pred comparator
}
size_t operator()(const _Kty& _Keyval) const
{ // hash _Keyval to size_t value
return ((size_t)_Keyval);
}
// size_t operator()(const _Kty& _Keyval) const
// { // hash _Keyval to size_t value by pseudorandomizing transform
// ldiv_t _Qrem = ldiv((size_t)_Keyval, 127773);
// _Qrem.rem = 16807 * _Qrem.rem - 2836 * _Qrem.quot;
// if (_Qrem.rem < 0)
// _Qrem.rem += 2147483647;
// return ((size_t)_Qrem.rem); }
bool operator()(const _Kty& _Keyval1, const _Kty& _Keyval2) const
{ // test if _Keyval1 ordered before _Keyval2
return (comp(_Keyval1, _Keyval2));
}
private:
_Pr comp; // the comparator object
};
// TEMPLATE CLASS _Hash
template<class _Tr>
class _Hash : public _Tr // traits serves as base class
{ // hash table -- list with vector of iterators for quick access
public:
typedef _Hash<_Tr> _Myt;
typedef typename _Tr::key_type key_type;
typedef typename _Tr::key_compare key_compare;
typedef typename _Tr::value_compare value_compare;
enum
{ // hoist constants from key_compare
bucket_size = key_compare::bucket_size,
min_buckets = key_compare::min_buckets,
_Multi = _Tr::_Multi};
typedef list<typename _Tr::value_type,
typename _Tr::allocator_type> _Mylist;
typedef typename _Mylist::allocator_type allocator_type;
typedef typename _Mylist::size_type size_type;
typedef typename _Mylist::difference_type difference_type;
typedef typename _Mylist::pointer pointer;
typedef typename _Mylist::const_pointer const_pointer;
typedef typename _Mylist::reference reference;
typedef typename _Mylist::const_reference const_reference;
typedef typename _Mylist::iterator iterator;
typedef typename _Mylist::const_iterator const_iterator;
typedef typename _Mylist::reverse_iterator
reverse_iterator;
typedef typename _Mylist::const_reverse_iterator
const_reverse_iterator;
typedef typename _Mylist::value_type value_type;
typedef vector<iterator,
typename allocator_type::_TEMPLATE_MEMBER
rebind<iterator>::other> _Myvec;
typedef pair<iterator, bool> _Pairib;
typedef pair<iterator, iterator> _Pairii;
typedef pair<const_iterator, const_iterator> _Paircc;
explicit _Hash(const key_compare& _Traits,
const allocator_type& _Al)
: _Tr(_Traits), _List(_Al),
_Vec(min_buckets + 1, end(), _Al),
_Mask(1), _Maxidx(1)
{ // construct empty hash table
}
_Hash(const value_type *_First, const value_type *_Last,
const key_compare& _Traits, const allocator_type& _Al)
: _Tr(_Traits), _List(_Al),
_Vec(min_buckets + 1, end(), _Al),
_Mask(1), _Maxidx(1)
{ // construct hash table from [_First, _Last) array
insert(_First, _Last);
}
_Hash(const _Myt& _Right)
: _Tr(_Right.comp), _List(_Right.get_allocator()),
_Vec(_Right.get_allocator())
{ // construct hash table by copying right
_Copy(_Right);
}
~_Hash()
{ // destroy hash table
}
_Myt& operator=(const _Myt& _Right)
{ // replace contents from _Right
if (this != &_Right)
_Copy(_Right);
return (*this);
}
iterator begin()
{ // return iterator for beginning of mutable sequence
return (_List.begin());
}
const_iterator begin() const
{ // return iterator for beginning of nonmutable sequence
return (_List.begin());
}
iterator end()
{ // return iterator for end of mutable sequence
return (_List.end());
}
const_iterator end() const
{ // return iterator for end of nonmutable sequence
return (_List.end());
}
reverse_iterator rbegin()
{ // return iterator for beginning of reversed mutable sequence
return (_List.rbegin());
}
const_reverse_iterator rbegin() const
{ // return iterator for beginning of reversed nonmutable sequence
return (_List.rbegin());
}
reverse_iterator rend()
{ // return iterator for end of reversed mutable sequence
return (_List.rend());
}
const_reverse_iterator rend() const
{ // return iterator for end of reversed nonmutable sequence
return (_List.rend());
}
size_type size() const
{ // return length of sequence
return (_List.size());
}
size_type max_size() const
{ // return maximum possible length of sequence
return (_List.max_size());
}
bool empty() const
{ // return true only if sequence is empty
return (_List.empty());
}
allocator_type get_allocator() const
{ // return allocator object for values
return (_List.get_allocator());
}
key_compare key_comp() const
{ // return object for comparing keys
return (this->comp);
}
value_compare value_comp() const
{ // return object for comparing values
return (value_compare(key_comp()));
}
_Pairib insert(const value_type& _Val)
{ // try to insert node with value _Val
iterator _Plist, _Where;
if (_Maxidx <= size() / bucket_size)
{ // too dense, need to grow hash table
if (_Vec.size() - 1 <= _Maxidx)
{ // table full, double its size
_Mask = ((_Vec.size() - 1) << 1) - 1;
_Vec.resize(_Mask + 2, end());
}
else if (_Mask < _Maxidx)
_Mask = (_Mask << 1) + 1;
size_type _Bucket = _Maxidx - (_Mask >> 1) - 1;
for (_Plist = _Vec[_Bucket]; _Plist != _Vec[_Bucket + 1]; )
if ((this->comp(this->_Kfn(*_Plist)) & _Mask) == _Bucket)
++_Plist; // leave element in old bucket
else
{ // move element to new bucket
iterator _Pnext = _Plist;
size_type _Idx;
for (_Idx = _Maxidx; _Bucket < _Idx; --_Idx)
{ // update end iterators if new bucket filled
if (_Vec[_Idx] != end())
break;
_Vec[_Idx] = _Plist;
}
if (++_Pnext == end())
break;
else
{ // not at end, move it
for (_Idx = _Bucket; _Plist == _Vec[_Idx]; --_Idx)
{ // update end iterators if moving first
++_Vec[_Idx];
if (_Idx == 0)
break;
}
_List.splice(end(), _List, _Plist);
_Plist = _Pnext;
_Vec[_Maxidx + 1] = end();
}
}
++_Maxidx; // open new bucket for hash lookup
}
size_type _Bucket = _Hashval(this->_Kfn(_Val));
for (_Plist = _Vec[_Bucket + 1]; _Plist != _Vec[_Bucket]; )
if (this->comp(this->_Kfn(_Val), this->_Kfn(*--_Plist)))
; // still too high in bucket list
else if (this->comp(this->_Kfn(*_Plist), this->_Kfn(_Val)))
{ // found insertion point, back up to it
++_Plist;
break;
}
else if (_Multi)
break; // equivalent, insert only if multi
else
return (_Pairib(_Plist, false)); // already present
_Where = _List.insert(_Plist, _Val); // insert new element
for (; _Plist == _Vec[_Bucket]; --_Bucket)
{ // update end iterators if new first bucket element
_Vec[_Bucket] = _Where;
if (_Bucket == 0)
break;
}
return (_Pairib(_Where, true)); // return iterator for new element
}
iterator insert(iterator, const value_type& _Val)
{ // try to insert node with value _Val, ignore hint
return (insert(_Val).first);
}
template<class _Iter>
void insert(_Iter _First, _Iter _Last)
{ // insert [_First, _Last) one at a time
for (; _First != _Last; ++_First)
insert(*_First);
}
iterator erase(iterator _Where)
{ // erase element at _Where
size_type _Bucket = _Hashval(this->_Kfn(*_Where));
for (; _Where == _Vec[_Bucket]; --_Bucket)
{ // update end iterators if erasing first
++_Vec[_Bucket];
if (_Bucket == 0)
break;
}
return (_List.erase(_Where));
}
iterator erase(iterator _First, iterator _Last)
{ // erase [_First, _Last)
if (_First == begin() && _Last == end())
{ // erase all
clear();
return (begin());
}
else
{ // partial erase, one at a time
while (_First != _Last)
erase(_First++);
return (_First);
}
}
size_type erase(const key_type& _Keyval)
{ // erase and count all that match _Keyval
_Pairii _Where = equal_range(_Keyval);
size_type _Num = 0;
_Distance(_Where.first, _Where.second, _Num);
erase(_Where.first, _Where.second);
return (_Num);
}
void erase(const key_type *_First, const key_type *_Last)
{ // erase all that match array of keys [_First, _Last)
for (; _First != _Last; ++_First)
erase(*_First);
}
void clear()
{ // erase all
_List.clear();
_Vec.assign(min_buckets + 1, end());
_Mask = 1;
_Maxidx = 1;
}
iterator find(const key_type& _Keyval)
{ // find an element in mutable hash table that matches _Keyval
return (lower_bound(_Keyval));
}
const_iterator find(const key_type& _Keyval) const
{ // find an element in nonmutable hash table that matches _Keyval
return (lower_bound(_Keyval));
}
size_type count(const key_type& _Keyval) const
{ // count all elements that match _Keyval
_Paircc _Ans = equal_range(_Keyval);
size_type _Num = 0;
_Distance(_Ans.first, _Ans.second, _Num);
return (_Num);
}
iterator lower_bound(const key_type& _Keyval)
{ // find leftmost not less than _Keyval in mutable hash table
size_type _Bucket = _Hashval(_Keyval);
iterator _Where;
for (_Where = _Vec[_Bucket]; _Where != _Vec[_Bucket + 1]; ++_Where)
if (!this->comp(this->_Kfn(*_Where), _Keyval))
return (this->comp(_Keyval,
this->_Kfn(*_Where)) ? end() : _Where);
return (end());
}
const_iterator lower_bound(const key_type& _Keyval) const
{ // find leftmost not less than _Keyval in nonmutable hash table
size_type _Bucket = _Hashval(_Keyval);
const_iterator _Where;
for (_Where = _Vec[_Bucket]; _Where != _Vec[_Bucket + 1]; ++_Where)
if (!this->comp(this->_Kfn(*_Where), _Keyval))
return (this->comp(_Keyval,
this->_Kfn(*_Where)) ? end() : _Where);
return (end());
}
iterator upper_bound(const key_type& _Keyval)
{ // find leftmost not greater than _Keyval in mutable hash table
size_type _Bucket = _Hashval(_Keyval);
iterator _Where;
for (_Where = _Vec[_Bucket + 1]; _Where != _Vec[_Bucket]; )
if (!this->comp(_Keyval, this->_Kfn(*--_Where)))
return (this->comp(this->_Kfn(*_Where),
_Keyval) ? end() : ++_Where);
return (end());
}
const_iterator upper_bound(const key_type& _Keyval) const
{ // find leftmost not greater than _Keyval in nonmutable hash table
size_type _Bucket = _Hashval(_Keyval);
const_iterator _Where;
for (_Where = _Vec[_Bucket + 1]; _Where != _Vec[_Bucket]; )
if (!this->comp(_Keyval, this->_Kfn(*--_Where)))
return (this->comp(this->_Kfn(*_Where),
_Keyval) ? end() : ++_Where);
return (end());
}
_Pairii equal_range(const key_type& _Keyval)
{ // find range equivalent to _Keyval in mutable hash table
size_type _Bucket = _Hashval(_Keyval);
iterator _First, _Where;
for (_Where = _Vec[_Bucket]; _Where != _Vec[_Bucket + 1]; ++_Where)
if (!this->comp(this->_Kfn(*_Where), _Keyval))
{ // found _First, look for end of range
for (_First = _Where; _Where != _Vec[_Bucket + 1]; ++_Where)
if (this->comp(_Keyval, this->_Kfn(*_Where)))
break;
if (_First == _Where)
break;
return (_Pairii(_First, _Where));
}
return (_Pairii(end(), end()));
}
_Paircc equal_range(const key_type& _Keyval) const
{ // find range equivalent to _Keyval in nonmutable hash table
size_type _Bucket = _Hashval(_Keyval);
iterator _First, _Where;
for (_Where = _Vec[_Bucket]; _Where != _Vec[_Bucket + 1]; ++_Where)
if (!this->comp(this->_Kfn(*_Where), _Keyval))
{ // found _First, look for end of range
for (_First = _Where; _Where != _Vec[_Bucket + 1]; ++_Where)
if (this->comp(_Keyval, this->_Kfn(*_Where)))
break;
if (_First == _Where)
break;
return (_Paircc(_First, _Where));
}
return (_Paircc(end(), end()));
}
void swap(_Myt& _Right)
{ // exchange contents with _Right
if (get_allocator() == _Right.get_allocator())
{ // same allocator, swap control information
_List.swap(_Right._List);
std::swap(_Vec, _Right._Vec);
std::swap(_Mask, _Right._Mask);
std::swap(_Maxidx, _Right._Maxidx);
std::swap(this->comp, _Right.comp);
}
else
{ // different allocator, do multiple assigns
_Myt _Tmp = *this; *this = _Right, _Right = _Tmp;
}
}
friend void swap(_Myt& _Left, _Myt& _Right)
{ // swap _Left and _Right trees
_Left.swap(_Right);
}
protected:
void _Copy(const _Myt& _Right)
{ // copy entire hash table
_Vec.resize(_Right._Vec.size(), end());
_Mask = _Right._Mask;
_Maxidx = _Right._Maxidx;
_List.clear();
_TRY_BEGIN
_List.insert(end(), _Right._List.begin(), _Right._List.end());
this->comp = _Right.comp;
_CATCH_ALL
_List.clear(); // list or compare copy failed, bail out
fill(_Vec.begin(), _Vec.end(), end());
_RERAISE;
_CATCH_END
iterator _Whereto = begin();
const_iterator _Wherefrom = _Right.begin();
for (size_type _Bucket = 0; _Bucket < _Vec.size(); )
if (_Wherefrom == _Right._Vec[_Bucket])
_Vec[_Bucket] = _Whereto, ++_Bucket;
else
++_Whereto, ++_Wherefrom;
}
size_type _Hashval(const key_type& _Keyval) const
{ // return hash value, masked and wrapped to current table size
size_type _Num = this->comp(_Keyval) & _Mask;
if (_Maxidx <= _Num)
_Num -= (_Mask >> 1) + 1;
return (_Num);
}
_Mylist _List; // the list of elements, must initialize before _Vec
_Myvec _Vec; // the vector of list iterators
size_type _Mask; // the key mask
size_type _Maxidx; // current maximum key value
};
// _Hash TEMPLATE OPERATORS
template<class _Tr> inline
bool operator==(const _Hash<_Tr>& _Left, const _Hash<_Tr>& _Right)
{ // test for hash table equality
return (_Left.size() == _Right.size()
&& equal(_Left.begin(), _Left.end(), _Right.begin()));
}
template<class _Tr> inline
bool operator!=(const _Hash<_Tr>& _Left, const _Hash<_Tr>& _Right)
{ // test for hash table inequality
return (!(_Left == _Right));
}
template<class _Tr> inline
bool operator<(const _Hash<_Tr>& _Left, const _Hash<_Tr>& _Right)
{ // test if _Left < _Right for hash tables
return (lexicographical_compare(_Left.begin(), _Left.end(),
_Right.begin(), _Right.end()));
}
template<class _Tr> inline
bool operator>(const _Hash<_Tr>& _Left, const _Hash<_Tr>& _Right)
{ // test if _Left > _Right for hash tables
return (_Right < _Left);
}
template<class _Tr> inline
bool operator<=(const _Hash<_Tr>& _Left, const _Hash<_Tr>& _Right)
{ // test if _Left <= _Right for hash tables
return (!(_Right < _Left));
}
template<class _Tr> inline
bool operator>=(const _Hash<_Tr>& _Left, const _Hash<_Tr>& _Right)
{ // test if _Left >= _Right for hash tables
return (!(_Left < _Right));
}
_STD_END
#pragma warning(default: 4127)
#pragma warning(pop)
#pragma pack(pop)
#endif /* _XHASH_ */
/*
* Copyright (c) 1992-2001 by P.J. Plauger. ALL RIGHTS RESERVED.
* Consult your license regarding permissions and restrictions.
V3.10:0009 */