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diff --git a/src/third_party/boost-1.69.0/boost/intrusive/splaytree_algorithms.hpp b/src/third_party/boost-1.69.0/boost/intrusive/splaytree_algorithms.hpp new file mode 100644 index 00000000000..6376d32afdf --- /dev/null +++ b/src/third_party/boost-1.69.0/boost/intrusive/splaytree_algorithms.hpp @@ -0,0 +1,754 @@ +///////////////////////////////////////////////////////////////////////////// +// +// (C) Copyright Ion Gaztanaga 2007-2014 +// +// Distributed under the Boost Software License, Version 1.0. +// (See accompanying file LICENSE_1_0.txt or copy at +// http://www.boost.org/LICENSE_1_0.txt) +// +// See http://www.boost.org/libs/intrusive for documentation. +// +///////////////////////////////////////////////////////////////////////////// +// The implementation of splay trees is based on the article and code published +// in C++ Users Journal "Implementing Splay Trees in C++" (September 1, 2005). +// +// The splay code has been modified and (supposedly) improved by Ion Gaztanaga. +// +// Here is the copyright notice of the original file containing the splay code: +// +// splay_tree.h -- implementation of a STL compatible splay tree. +// +// Copyright (c) 2004 Ralf Mattethat +// +// Permission to copy, use, modify, sell and distribute this software +// is granted provided this copyright notice appears in all copies. +// This software is provided "as is" without express or implied +// warranty, and with no claim as to its suitability for any purpose. +// +///////////////////////////////////////////////////////////////////////////// + +#ifndef BOOST_INTRUSIVE_SPLAYTREE_ALGORITHMS_HPP +#define BOOST_INTRUSIVE_SPLAYTREE_ALGORITHMS_HPP + +#include <boost/intrusive/detail/config_begin.hpp> +#include <boost/intrusive/intrusive_fwd.hpp> +#include <boost/intrusive/detail/assert.hpp> +#include <boost/intrusive/detail/algo_type.hpp> +#include <boost/intrusive/detail/uncast.hpp> +#include <boost/intrusive/bstree_algorithms.hpp> + +#include <cstddef> + +#if defined(BOOST_HAS_PRAGMA_ONCE) +# pragma once +#endif + +namespace boost { +namespace intrusive { + +/// @cond +namespace detail { + +template<class NodeTraits> +struct splaydown_assemble_and_fix_header +{ + typedef typename NodeTraits::node_ptr node_ptr; + + splaydown_assemble_and_fix_header(node_ptr t, node_ptr header, node_ptr leftmost, node_ptr rightmost) + : t_(t) + , null_node_(header) + , l_(null_node_) + , r_(null_node_) + , leftmost_(leftmost) + , rightmost_(rightmost) + {} + + ~splaydown_assemble_and_fix_header() + { + this->assemble(); + + //Now recover the original header except for the + //splayed root node. + //"t_" is the current root and "null_node_" is the header node + NodeTraits::set_parent(null_node_, t_); + NodeTraits::set_parent(t_, null_node_); + //Recover leftmost/rightmost pointers + NodeTraits::set_left (null_node_, leftmost_); + NodeTraits::set_right(null_node_, rightmost_); + } + + private: + + void assemble() + { + //procedure assemble; + // left(r), right(l) := right(t), left(t); + // left(t), right(t) := right(null), left(null); + //end assemble; + { // left(r), right(l) := right(t), left(t); + + node_ptr const old_t_left = NodeTraits::get_left(t_); + node_ptr const old_t_right = NodeTraits::get_right(t_); + NodeTraits::set_right(l_, old_t_left); + NodeTraits::set_left (r_, old_t_right); + if(old_t_left){ + NodeTraits::set_parent(old_t_left, l_); + } + if(old_t_right){ + NodeTraits::set_parent(old_t_right, r_); + } + } + { // left(t), right(t) := right(null), left(null); + node_ptr const null_right = NodeTraits::get_right(null_node_); + node_ptr const null_left = NodeTraits::get_left(null_node_); + NodeTraits::set_left (t_, null_right); + NodeTraits::set_right(t_, null_left); + if(null_right){ + NodeTraits::set_parent(null_right, t_); + } + if(null_left){ + NodeTraits::set_parent(null_left, t_); + } + } + } + + public: + node_ptr t_, null_node_, l_, r_, leftmost_, rightmost_; +}; + +} //namespace detail { +/// @endcond + +//! A splay tree is an implementation of a binary search tree. The tree is +//! self balancing using the splay algorithm as described in +//! +//! "Self-Adjusting Binary Search Trees +//! by Daniel Dominic Sleator and Robert Endre Tarjan +//! AT&T Bell Laboratories, Murray Hill, NJ +//! Journal of the ACM, Vol 32, no 3, July 1985, pp 652-686 +//! +//! splaytree_algorithms is configured with a NodeTraits class, which encapsulates the +//! information about the node to be manipulated. NodeTraits must support the +//! following interface: +//! +//! <b>Typedefs</b>: +//! +//! <tt>node</tt>: The type of the node that forms the binary search tree +//! +//! <tt>node_ptr</tt>: A pointer to a node +//! +//! <tt>const_node_ptr</tt>: A pointer to a const node +//! +//! <b>Static functions</b>: +//! +//! <tt>static node_ptr get_parent(const_node_ptr n);</tt> +//! +//! <tt>static void set_parent(node_ptr n, node_ptr parent);</tt> +//! +//! <tt>static node_ptr get_left(const_node_ptr n);</tt> +//! +//! <tt>static void set_left(node_ptr n, node_ptr left);</tt> +//! +//! <tt>static node_ptr get_right(const_node_ptr n);</tt> +//! +//! <tt>static void set_right(node_ptr n, node_ptr right);</tt> +template<class NodeTraits> +class splaytree_algorithms + #ifndef BOOST_INTRUSIVE_DOXYGEN_INVOKED + : public bstree_algorithms<NodeTraits> + #endif +{ + /// @cond + private: + typedef bstree_algorithms<NodeTraits> bstree_algo; + /// @endcond + + public: + typedef typename NodeTraits::node node; + typedef NodeTraits node_traits; + typedef typename NodeTraits::node_ptr node_ptr; + typedef typename NodeTraits::const_node_ptr const_node_ptr; + + //! This type is the information that will be + //! filled by insert_unique_check + typedef typename bstree_algo::insert_commit_data insert_commit_data; + + public: + #ifdef BOOST_INTRUSIVE_DOXYGEN_INVOKED + //! @copydoc ::boost::intrusive::bstree_algorithms::get_header(const const_node_ptr&) + static node_ptr get_header(const const_node_ptr & n); + + //! @copydoc ::boost::intrusive::bstree_algorithms::begin_node + static node_ptr begin_node(const const_node_ptr & header); + + //! @copydoc ::boost::intrusive::bstree_algorithms::end_node + static node_ptr end_node(const const_node_ptr & header); + + //! @copydoc ::boost::intrusive::bstree_algorithms::swap_tree + static void swap_tree(const node_ptr & header1, const node_ptr & header2); + + //! @copydoc ::boost::intrusive::bstree_algorithms::swap_nodes(node_ptr,node_ptr) + static void swap_nodes(node_ptr node1, node_ptr node2); + + //! @copydoc ::boost::intrusive::bstree_algorithms::swap_nodes(node_ptr,node_ptr,node_ptr,node_ptr) + static void swap_nodes(node_ptr node1, node_ptr header1, node_ptr node2, node_ptr header2); + + //! @copydoc ::boost::intrusive::bstree_algorithms::replace_node(node_ptr,node_ptr) + static void replace_node(node_ptr node_to_be_replaced, node_ptr new_node); + + //! @copydoc ::boost::intrusive::bstree_algorithms::replace_node(node_ptr,node_ptr,node_ptr) + static void replace_node(node_ptr node_to_be_replaced, node_ptr header, node_ptr new_node); + + //! @copydoc ::boost::intrusive::bstree_algorithms::unlink(node_ptr) + static void unlink(node_ptr node); + + //! @copydoc ::boost::intrusive::bstree_algorithms::unlink_leftmost_without_rebalance + static node_ptr unlink_leftmost_without_rebalance(node_ptr header); + + //! @copydoc ::boost::intrusive::bstree_algorithms::unique(const const_node_ptr&) + static bool unique(const_node_ptr node); + + //! @copydoc ::boost::intrusive::bstree_algorithms::size(const const_node_ptr&) + static std::size_t size(const_node_ptr header); + + //! @copydoc ::boost::intrusive::bstree_algorithms::next_node(const node_ptr&) + static node_ptr next_node(node_ptr node); + + //! @copydoc ::boost::intrusive::bstree_algorithms::prev_node(const node_ptr&) + static node_ptr prev_node(node_ptr node); + + //! @copydoc ::boost::intrusive::bstree_algorithms::init(node_ptr) + static void init(node_ptr node); + + //! @copydoc ::boost::intrusive::bstree_algorithms::init_header(node_ptr) + static void init_header(node_ptr header); + + #endif //#ifdef BOOST_INTRUSIVE_DOXYGEN_INVOKED + + //! @copydoc ::boost::intrusive::bstree_algorithms::erase(node_ptr,node_ptr) + //! Additional notes: the previous node of z is splayed to speed up range deletions. + static void erase(node_ptr header, node_ptr z) + { + //posibility 1 + if(NodeTraits::get_left(z)){ + splay_up(bstree_algo::prev_node(z), header); + } + + //possibility 2 + //if(NodeTraits::get_left(z)){ + // node_ptr l = NodeTraits::get_left(z); + // splay_up(l, header); + //} + + //if(NodeTraits::get_left(z)){ + // node_ptr l = bstree_algo::prev_node(z); + // splay_up_impl(l, z); + //} + + //possibility 4 + //splay_up(z, header); + + bstree_algo::erase(header, z); + } + + //! @copydoc ::boost::intrusive::bstree_algorithms::transfer_unique + template<class NodePtrCompare> + static bool transfer_unique + (node_ptr header1, NodePtrCompare comp, node_ptr header2, node_ptr z) + { + typename bstree_algo::insert_commit_data commit_data; + bool const transferable = bstree_algo::insert_unique_check(header1, z, comp, commit_data).second; + if(transferable){ + erase(header2, z); + bstree_algo::insert_commit(header1, z, commit_data); + splay_up(z, header1); + } + return transferable; + } + + //! @copydoc ::boost::intrusive::bstree_algorithms::transfer_equal + template<class NodePtrCompare> + static void transfer_equal + (node_ptr header1, NodePtrCompare comp, node_ptr header2, node_ptr z) + { + insert_commit_data commit_data; + splay_down(header1, z, comp); + bstree_algo::insert_equal_upper_bound_check(header1, z, comp, commit_data); + erase(header2, z); + bstree_algo::insert_commit(header1, z, commit_data); + } + + #ifdef BOOST_INTRUSIVE_DOXYGEN_INVOKED + //! @copydoc ::boost::intrusive::bstree_algorithms::clone(const const_node_ptr&,node_ptr,Cloner,Disposer) + template <class Cloner, class Disposer> + static void clone + (const_node_ptr source_header, node_ptr target_header, Cloner cloner, Disposer disposer); + + //! @copydoc ::boost::intrusive::bstree_algorithms::clear_and_dispose(const node_ptr&,Disposer) + template<class Disposer> + static void clear_and_dispose(node_ptr header, Disposer disposer); + + #endif //#ifdef BOOST_INTRUSIVE_DOXYGEN_INVOKED + //! @copydoc ::boost::intrusive::bstree_algorithms::count(const const_node_ptr&,const KeyType&,KeyNodePtrCompare) + //! Additional notes: an element with key `key` is splayed. + template<class KeyType, class KeyNodePtrCompare> + static std::size_t count + (node_ptr header, const KeyType &key, KeyNodePtrCompare comp) + { + std::pair<node_ptr, node_ptr> ret = equal_range(header, key, comp); + std::size_t n = 0; + while(ret.first != ret.second){ + ++n; + ret.first = next_node(ret.first); + } + return n; + } + + //! @copydoc ::boost::intrusive::bstree_algorithms::count(const const_node_ptr&,const KeyType&,KeyNodePtrCompare) + //! Additional note: no splaying is performed + template<class KeyType, class KeyNodePtrCompare> + static std::size_t count + (const_node_ptr header, const KeyType &key, KeyNodePtrCompare comp) + { return bstree_algo::count(header, key, comp); } + + //! @copydoc ::boost::intrusive::bstree_algorithms::lower_bound(const const_node_ptr&,const KeyType&,KeyNodePtrCompare) + //! Additional notes: the first node of the range is splayed. + template<class KeyType, class KeyNodePtrCompare> + static node_ptr lower_bound + (node_ptr header, const KeyType &key, KeyNodePtrCompare comp) + { + splay_down(detail::uncast(header), key, comp); + node_ptr y = bstree_algo::lower_bound(header, key, comp); + //splay_up(y, detail::uncast(header)); + return y; + } + + //! @copydoc ::boost::intrusive::bstree_algorithms::lower_bound(const const_node_ptr&,const KeyType&,KeyNodePtrCompare) + //! Additional note: no splaying is performed + template<class KeyType, class KeyNodePtrCompare> + static node_ptr lower_bound + (const_node_ptr header, const KeyType &key, KeyNodePtrCompare comp) + { return bstree_algo::lower_bound(header, key, comp); } + + //! @copydoc ::boost::intrusive::bstree_algorithms::upper_bound(const const_node_ptr&,const KeyType&,KeyNodePtrCompare) + //! Additional notes: the first node of the range is splayed. + template<class KeyType, class KeyNodePtrCompare> + static node_ptr upper_bound + (node_ptr header, const KeyType &key, KeyNodePtrCompare comp) + { + splay_down(detail::uncast(header), key, comp); + node_ptr y = bstree_algo::upper_bound(header, key, comp); + //splay_up(y, detail::uncast(header)); + return y; + } + + //! @copydoc ::boost::intrusive::bstree_algorithms::upper_bound(const const_node_ptr&,const KeyType&,KeyNodePtrCompare) + //! Additional note: no splaying is performed + template<class KeyType, class KeyNodePtrCompare> + static node_ptr upper_bound + (const_node_ptr header, const KeyType &key, KeyNodePtrCompare comp) + { return bstree_algo::upper_bound(header, key, comp); } + + //! @copydoc ::boost::intrusive::bstree_algorithms::find(const const_node_ptr&, const KeyType&,KeyNodePtrCompare) + //! Additional notes: the found node of the lower bound is splayed. + template<class KeyType, class KeyNodePtrCompare> + static node_ptr find + (node_ptr header, const KeyType &key, KeyNodePtrCompare comp) + { + splay_down(detail::uncast(header), key, comp); + return bstree_algo::find(header, key, comp); + } + + //! @copydoc ::boost::intrusive::bstree_algorithms::find(const const_node_ptr&, const KeyType&,KeyNodePtrCompare) + //! Additional note: no splaying is performed + template<class KeyType, class KeyNodePtrCompare> + static node_ptr find + (const_node_ptr header, const KeyType &key, KeyNodePtrCompare comp) + { return bstree_algo::find(header, key, comp); } + + //! @copydoc ::boost::intrusive::bstree_algorithms::equal_range(const const_node_ptr&,const KeyType&,KeyNodePtrCompare) + //! Additional notes: the first node of the range is splayed. + template<class KeyType, class KeyNodePtrCompare> + static std::pair<node_ptr, node_ptr> equal_range + (node_ptr header, const KeyType &key, KeyNodePtrCompare comp) + { + splay_down(detail::uncast(header), key, comp); + std::pair<node_ptr, node_ptr> ret = bstree_algo::equal_range(header, key, comp); + //splay_up(ret.first, detail::uncast(header)); + return ret; + } + + //! @copydoc ::boost::intrusive::bstree_algorithms::equal_range(const const_node_ptr&,const KeyType&,KeyNodePtrCompare) + //! Additional note: no splaying is performed + template<class KeyType, class KeyNodePtrCompare> + static std::pair<node_ptr, node_ptr> equal_range + (const_node_ptr header, const KeyType &key, KeyNodePtrCompare comp) + { return bstree_algo::equal_range(header, key, comp); } + + //! @copydoc ::boost::intrusive::bstree_algorithms::lower_bound_range(const const_node_ptr&,const KeyType&,KeyNodePtrCompare) + //! Additional notes: the first node of the range is splayed. + template<class KeyType, class KeyNodePtrCompare> + static std::pair<node_ptr, node_ptr> lower_bound_range + (node_ptr header, const KeyType &key, KeyNodePtrCompare comp) + { + splay_down(detail::uncast(header), key, comp); + std::pair<node_ptr, node_ptr> ret = bstree_algo::lower_bound_range(header, key, comp); + //splay_up(ret.first, detail::uncast(header)); + return ret; + } + + //! @copydoc ::boost::intrusive::bstree_algorithms::lower_bound_range(const const_node_ptr&,const KeyType&,KeyNodePtrCompare) + //! Additional note: no splaying is performed + template<class KeyType, class KeyNodePtrCompare> + static std::pair<node_ptr, node_ptr> lower_bound_range + (const_node_ptr header, const KeyType &key, KeyNodePtrCompare comp) + { return bstree_algo::lower_bound_range(header, key, comp); } + + //! @copydoc ::boost::intrusive::bstree_algorithms::bounded_range(const const_node_ptr&,const KeyType&,const KeyType&,KeyNodePtrCompare,bool,bool) + //! Additional notes: the first node of the range is splayed. + template<class KeyType, class KeyNodePtrCompare> + static std::pair<node_ptr, node_ptr> bounded_range + (node_ptr header, const KeyType &lower_key, const KeyType &upper_key, KeyNodePtrCompare comp + , bool left_closed, bool right_closed) + { + splay_down(detail::uncast(header), lower_key, comp); + std::pair<node_ptr, node_ptr> ret = + bstree_algo::bounded_range(header, lower_key, upper_key, comp, left_closed, right_closed); + //splay_up(ret.first, detail::uncast(header)); + return ret; + } + + //! @copydoc ::boost::intrusive::bstree_algorithms::bounded_range(const const_node_ptr&,const KeyType&,const KeyType&,KeyNodePtrCompare,bool,bool) + //! Additional note: no splaying is performed + template<class KeyType, class KeyNodePtrCompare> + static std::pair<node_ptr, node_ptr> bounded_range + (const_node_ptr header, const KeyType &lower_key, const KeyType &upper_key, KeyNodePtrCompare comp + , bool left_closed, bool right_closed) + { return bstree_algo::bounded_range(header, lower_key, upper_key, comp, left_closed, right_closed); } + + //! @copydoc ::boost::intrusive::bstree_algorithms::insert_equal_upper_bound(node_ptr,node_ptr,NodePtrCompare) + //! Additional note: the inserted node is splayed + template<class NodePtrCompare> + static node_ptr insert_equal_upper_bound + (node_ptr header, node_ptr new_node, NodePtrCompare comp) + { + splay_down(header, new_node, comp); + return bstree_algo::insert_equal_upper_bound(header, new_node, comp); + } + + //! @copydoc ::boost::intrusive::bstree_algorithms::insert_equal_lower_bound(node_ptr,node_ptr,NodePtrCompare) + //! Additional note: the inserted node is splayed + template<class NodePtrCompare> + static node_ptr insert_equal_lower_bound + (node_ptr header, node_ptr new_node, NodePtrCompare comp) + { + splay_down(header, new_node, comp); + return bstree_algo::insert_equal_lower_bound(header, new_node, comp); + } + + //! @copydoc ::boost::intrusive::bstree_algorithms::insert_equal(node_ptr,node_ptr,node_ptr,NodePtrCompare) + //! Additional note: the inserted node is splayed + template<class NodePtrCompare> + static node_ptr insert_equal + (node_ptr header, node_ptr hint, node_ptr new_node, NodePtrCompare comp) + { + splay_down(header, new_node, comp); + return bstree_algo::insert_equal(header, hint, new_node, comp); + } + + //! @copydoc ::boost::intrusive::bstree_algorithms::insert_before(node_ptr,node_ptr,node_ptr) + //! Additional note: the inserted node is splayed + static node_ptr insert_before + (node_ptr header, node_ptr pos, node_ptr new_node) + { + bstree_algo::insert_before(header, pos, new_node); + splay_up(new_node, header); + return new_node; + } + + //! @copydoc ::boost::intrusive::bstree_algorithms::push_back(node_ptr,node_ptr) + //! Additional note: the inserted node is splayed + static void push_back(node_ptr header, node_ptr new_node) + { + bstree_algo::push_back(header, new_node); + splay_up(new_node, header); + } + + //! @copydoc ::boost::intrusive::bstree_algorithms::push_front(node_ptr,node_ptr) + //! Additional note: the inserted node is splayed + static void push_front(node_ptr header, node_ptr new_node) + { + bstree_algo::push_front(header, new_node); + splay_up(new_node, header); + } + + //! @copydoc ::boost::intrusive::bstree_algorithms::insert_unique_check(const const_node_ptr&,const KeyType&,KeyNodePtrCompare,insert_commit_data&) + //! Additional note: nodes with the given key are splayed + template<class KeyType, class KeyNodePtrCompare> + static std::pair<node_ptr, bool> insert_unique_check + (node_ptr header, const KeyType &key + ,KeyNodePtrCompare comp, insert_commit_data &commit_data) + { + splay_down(header, key, comp); + return bstree_algo::insert_unique_check(header, key, comp, commit_data); + } + + //! @copydoc ::boost::intrusive::bstree_algorithms::insert_unique_check(const const_node_ptr&,const node_ptr&,const KeyType&,KeyNodePtrCompare,insert_commit_data&) + //! Additional note: nodes with the given key are splayed + template<class KeyType, class KeyNodePtrCompare> + static std::pair<node_ptr, bool> insert_unique_check + (node_ptr header, node_ptr hint, const KeyType &key + ,KeyNodePtrCompare comp, insert_commit_data &commit_data) + { + splay_down(header, key, comp); + return bstree_algo::insert_unique_check(header, hint, key, comp, commit_data); + } + + #ifdef BOOST_INTRUSIVE_DOXYGEN_INVOKED + //! @copydoc ::boost::intrusive::bstree_algorithms::insert_unique_commit(node_ptr,node_ptr,const insert_commit_data&) + static void insert_unique_commit + (node_ptr header, node_ptr new_value, const insert_commit_data &commit_data); + + //! @copydoc ::boost::intrusive::bstree_algorithms::is_header + static bool is_header(const_node_ptr p); + + //! @copydoc ::boost::intrusive::bstree_algorithms::rebalance + static void rebalance(node_ptr header); + + //! @copydoc ::boost::intrusive::bstree_algorithms::rebalance_subtree + static node_ptr rebalance_subtree(node_ptr old_root); + + #endif //#ifdef BOOST_INTRUSIVE_DOXYGEN_INVOKED + + // bottom-up splay, use data_ as parent for n | complexity : logarithmic | exception : nothrow + static void splay_up(node_ptr node, node_ptr header) + { priv_splay_up<true>(node, header); } + + // top-down splay | complexity : logarithmic | exception : strong, note A + template<class KeyType, class KeyNodePtrCompare> + static node_ptr splay_down(node_ptr header, const KeyType &key, KeyNodePtrCompare comp, bool *pfound = 0) + { return priv_splay_down<true>(header, key, comp, pfound); } + + private: + + /// @cond + + // bottom-up splay, use data_ as parent for n | complexity : logarithmic | exception : nothrow + template<bool SimpleSplay> + static void priv_splay_up(node_ptr node, node_ptr header) + { + // If (node == header) do a splay for the right most node instead + // this is to boost performance of equal_range/count on equivalent containers in the case + // where there are many equal elements at the end + node_ptr n((node == header) ? NodeTraits::get_right(header) : node); + node_ptr t(header); + + if( n == t ) return; + + for( ;; ){ + node_ptr p(NodeTraits::get_parent(n)); + node_ptr g(NodeTraits::get_parent(p)); + + if( p == t ) break; + + if( g == t ){ + // zig + rotate(n); + } + else if ((NodeTraits::get_left(p) == n && NodeTraits::get_left(g) == p) || + (NodeTraits::get_right(p) == n && NodeTraits::get_right(g) == p) ){ + // zig-zig + rotate(p); + rotate(n); + } + else { + // zig-zag + rotate(n); + if(!SimpleSplay){ + rotate(n); + } + } + } + } + + template<bool SimpleSplay, class KeyType, class KeyNodePtrCompare> + static node_ptr priv_splay_down(node_ptr header, const KeyType &key, KeyNodePtrCompare comp, bool *pfound = 0) + { + //Most splay tree implementations use a dummy/null node to implement. + //this function. This has some problems for a generic library like Intrusive: + // + // * The node might not have a default constructor. + // * The default constructor could throw. + // + //We already have a header node. Leftmost and rightmost nodes of the tree + //are not changed when splaying (because the invariants of the tree don't + //change) We can back up them, use the header as the null node and + //reassign old values after the function has been completed. + node_ptr const old_root = NodeTraits::get_parent(header); + node_ptr const leftmost = NodeTraits::get_left(header); + node_ptr const rightmost = NodeTraits::get_right(header); + if(leftmost == rightmost){ //Empty or unique node + if(pfound){ + *pfound = old_root && !comp(key, old_root) && !comp(old_root, key); + } + return old_root ? old_root : header; + } + else{ + //Initialize "null node" (the header in our case) + NodeTraits::set_left (header, node_ptr()); + NodeTraits::set_right(header, node_ptr()); + //Class that will backup leftmost/rightmost from header, commit the assemble(), + //and will restore leftmost/rightmost to header even if "comp" throws + detail::splaydown_assemble_and_fix_header<NodeTraits> commit(old_root, header, leftmost, rightmost); + bool found = false; + + for( ;; ){ + if(comp(key, commit.t_)){ + node_ptr const t_left = NodeTraits::get_left(commit.t_); + if(!t_left) + break; + if(comp(key, t_left)){ + bstree_algo::rotate_right_no_parent_fix(commit.t_, t_left); + commit.t_ = t_left; + if( !NodeTraits::get_left(commit.t_) ) + break; + link_right(commit.t_, commit.r_); + } + else{ + link_right(commit.t_, commit.r_); + if(!SimpleSplay && comp(t_left, key)){ + if( !NodeTraits::get_right(commit.t_) ) + break; + link_left(commit.t_, commit.l_); + } + } + } + else if(comp(commit.t_, key)){ + node_ptr const t_right = NodeTraits::get_right(commit.t_); + if(!t_right) + break; + + if(comp(t_right, key)){ + bstree_algo::rotate_left_no_parent_fix(commit.t_, t_right); + commit.t_ = t_right; + if( !NodeTraits::get_right(commit.t_) ) + break; + link_left(commit.t_, commit.l_); + } + else{ + link_left(commit.t_, commit.l_); + if(!SimpleSplay && comp(key, t_right)){ + if( !NodeTraits::get_left(commit.t_) ) + break; + link_right(commit.t_, commit.r_); + } + } + } + else{ + found = true; + break; + } + } + + //commit.~splaydown_assemble_and_fix_header<NodeTraits>() will first + //"assemble()" + link the new root & recover header's leftmost & rightmost + if(pfound){ + *pfound = found; + } + return commit.t_; + } + } + + // break link to left child node and attach it to left tree pointed to by l | complexity : constant | exception : nothrow + static void link_left(node_ptr & t, node_ptr & l) + { + //procedure link_left; + // t, l, right(l) := right(t), t, t + //end link_left + NodeTraits::set_right(l, t); + NodeTraits::set_parent(t, l); + l = t; + t = NodeTraits::get_right(t); + } + + // break link to right child node and attach it to right tree pointed to by r | complexity : constant | exception : nothrow + static void link_right(node_ptr & t, node_ptr & r) + { + //procedure link_right; + // t, r, left(r) := left(t), t, t + //end link_right; + NodeTraits::set_left(r, t); + NodeTraits::set_parent(t, r); + r = t; + t = NodeTraits::get_left(t); + } + + // rotate n with its parent | complexity : constant | exception : nothrow + static void rotate(node_ptr n) + { + //procedure rotate_left; + // t, right(t), left(right(t)) := right(t), left(right(t)), t + //end rotate_left; + node_ptr p = NodeTraits::get_parent(n); + node_ptr g = NodeTraits::get_parent(p); + //Test if g is header before breaking tree + //invariants that would make is_header invalid + bool g_is_header = bstree_algo::is_header(g); + + if(NodeTraits::get_left(p) == n){ + NodeTraits::set_left(p, NodeTraits::get_right(n)); + if(NodeTraits::get_left(p)) + NodeTraits::set_parent(NodeTraits::get_left(p), p); + NodeTraits::set_right(n, p); + } + else{ // must be ( p->right == n ) + NodeTraits::set_right(p, NodeTraits::get_left(n)); + if(NodeTraits::get_right(p)) + NodeTraits::set_parent(NodeTraits::get_right(p), p); + NodeTraits::set_left(n, p); + } + + NodeTraits::set_parent(p, n); + NodeTraits::set_parent(n, g); + + if(g_is_header){ + if(NodeTraits::get_parent(g) == p) + NodeTraits::set_parent(g, n); + else{//must be ( g->right == p ) + BOOST_INTRUSIVE_INVARIANT_ASSERT(false); + NodeTraits::set_right(g, n); + } + } + else{ + if(NodeTraits::get_left(g) == p) + NodeTraits::set_left(g, n); + else //must be ( g->right == p ) + NodeTraits::set_right(g, n); + } + } + + /// @endcond +}; + +/// @cond + +template<class NodeTraits> +struct get_algo<SplayTreeAlgorithms, NodeTraits> +{ + typedef splaytree_algorithms<NodeTraits> type; +}; + +template <class ValueTraits, class NodePtrCompare, class ExtraChecker> +struct get_node_checker<SplayTreeAlgorithms, ValueTraits, NodePtrCompare, ExtraChecker> +{ + typedef detail::bstree_node_checker<ValueTraits, NodePtrCompare, ExtraChecker> type; +}; + +/// @endcond + +} //namespace intrusive +} //namespace boost + +#include <boost/intrusive/detail/config_end.hpp> + +#endif //BOOST_INTRUSIVE_SPLAYTREE_ALGORITHMS_HPP |