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// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_CONTAINER_INTERNAL_BTREE_CONTAINER_H_
#define ABSL_CONTAINER_INTERNAL_BTREE_CONTAINER_H_
#include <algorithm>
#include <initializer_list>
#include <iterator>
#include <utility>
#include "absl/base/internal/throw_delegate.h"
#include "absl/container/internal/btree.h" // IWYU pragma: export
#include "absl/container/internal/common.h"
#include "absl/memory/memory.h"
#include "absl/meta/type_traits.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
// A common base class for btree_set, btree_map, btree_multiset, and
// btree_multimap.
template <typename Tree>
class btree_container {
using params_type = typename Tree::params_type;
protected:
// Alias used for heterogeneous lookup functions.
// `key_arg<K>` evaluates to `K` when the functors are transparent and to
// `key_type` otherwise. It permits template argument deduction on `K` for the
// transparent case.
template <class K>
using key_arg =
typename KeyArg<IsTransparent<typename Tree::key_compare>::value>::
template type<K, typename Tree::key_type>;
public:
using key_type = typename Tree::key_type;
using value_type = typename Tree::value_type;
using size_type = typename Tree::size_type;
using difference_type = typename Tree::difference_type;
using key_compare = typename Tree::key_compare;
using value_compare = typename Tree::value_compare;
using allocator_type = typename Tree::allocator_type;
using reference = typename Tree::reference;
using const_reference = typename Tree::const_reference;
using pointer = typename Tree::pointer;
using const_pointer = typename Tree::const_pointer;
using iterator = typename Tree::iterator;
using const_iterator = typename Tree::const_iterator;
using reverse_iterator = typename Tree::reverse_iterator;
using const_reverse_iterator = typename Tree::const_reverse_iterator;
using node_type = typename Tree::node_handle_type;
// Constructors/assignments.
btree_container() : tree_(key_compare(), allocator_type()) {}
explicit btree_container(const key_compare &comp,
const allocator_type &alloc = allocator_type())
: tree_(comp, alloc) {}
explicit btree_container(const allocator_type &alloc)
: tree_(key_compare(), alloc) {}
btree_container(const btree_container &other)
: btree_container(other, absl::allocator_traits<allocator_type>::
select_on_container_copy_construction(
other.get_allocator())) {}
btree_container(const btree_container &other, const allocator_type &alloc)
: tree_(other.tree_, alloc) {}
btree_container(btree_container &&other) noexcept(
std::is_nothrow_move_constructible<Tree>::value) = default;
btree_container(btree_container &&other, const allocator_type &alloc)
: tree_(std::move(other.tree_), alloc) {}
btree_container &operator=(const btree_container &other) = default;
btree_container &operator=(btree_container &&other) noexcept(
std::is_nothrow_move_assignable<Tree>::value) = default;
// Iterator routines.
iterator begin() { return tree_.begin(); }
const_iterator begin() const { return tree_.begin(); }
const_iterator cbegin() const { return tree_.begin(); }
iterator end() { return tree_.end(); }
const_iterator end() const { return tree_.end(); }
const_iterator cend() const { return tree_.end(); }
reverse_iterator rbegin() { return tree_.rbegin(); }
const_reverse_iterator rbegin() const { return tree_.rbegin(); }
const_reverse_iterator crbegin() const { return tree_.rbegin(); }
reverse_iterator rend() { return tree_.rend(); }
const_reverse_iterator rend() const { return tree_.rend(); }
const_reverse_iterator crend() const { return tree_.rend(); }
// Lookup routines.
template <typename K = key_type>
size_type count(const key_arg<K> &key) const {
auto equal_range = this->equal_range(key);
return std::distance(equal_range.first, equal_range.second);
}
template <typename K = key_type>
iterator find(const key_arg<K> &key) {
return tree_.find(key);
}
template <typename K = key_type>
const_iterator find(const key_arg<K> &key) const {
return tree_.find(key);
}
template <typename K = key_type>
bool contains(const key_arg<K> &key) const {
return find(key) != end();
}
template <typename K = key_type>
iterator lower_bound(const key_arg<K> &key) {
return tree_.lower_bound(key);
}
template <typename K = key_type>
const_iterator lower_bound(const key_arg<K> &key) const {
return tree_.lower_bound(key);
}
template <typename K = key_type>
iterator upper_bound(const key_arg<K> &key) {
return tree_.upper_bound(key);
}
template <typename K = key_type>
const_iterator upper_bound(const key_arg<K> &key) const {
return tree_.upper_bound(key);
}
template <typename K = key_type>
std::pair<iterator, iterator> equal_range(const key_arg<K> &key) {
return tree_.equal_range(key);
}
template <typename K = key_type>
std::pair<const_iterator, const_iterator> equal_range(
const key_arg<K> &key) const {
return tree_.equal_range(key);
}
// Deletion routines. Note that there is also a deletion routine that is
// specific to btree_set_container/btree_multiset_container.
// Erase the specified iterator from the btree. The iterator must be valid
// (i.e. not equal to end()). Return an iterator pointing to the node after
// the one that was erased (or end() if none exists).
iterator erase(const_iterator iter) { return tree_.erase(iterator(iter)); }
iterator erase(iterator iter) { return tree_.erase(iter); }
iterator erase(const_iterator first, const_iterator last) {
return tree_.erase_range(iterator(first), iterator(last)).second;
}
template <typename K = key_type>
size_type erase(const key_arg<K> &key) {
auto equal_range = this->equal_range(key);
return tree_.erase_range(equal_range.first, equal_range.second).first;
}
// Extract routines.
node_type extract(iterator position) {
// Use Move instead of Transfer, because the rebalancing code expects to
// have a valid object to scribble metadata bits on top of.
auto node = CommonAccess::Move<node_type>(get_allocator(), position.slot());
erase(position);
return node;
}
node_type extract(const_iterator position) {
return extract(iterator(position));
}
// Utility routines.
void clear() { tree_.clear(); }
void swap(btree_container &other) { tree_.swap(other.tree_); }
void verify() const { tree_.verify(); }
// Size routines.
size_type size() const { return tree_.size(); }
size_type max_size() const { return tree_.max_size(); }
bool empty() const { return tree_.empty(); }
friend bool operator==(const btree_container &x, const btree_container &y) {
if (x.size() != y.size()) return false;
return std::equal(x.begin(), x.end(), y.begin());
}
friend bool operator!=(const btree_container &x, const btree_container &y) {
return !(x == y);
}
friend bool operator<(const btree_container &x, const btree_container &y) {
return std::lexicographical_compare(x.begin(), x.end(), y.begin(), y.end());
}
friend bool operator>(const btree_container &x, const btree_container &y) {
return y < x;
}
friend bool operator<=(const btree_container &x, const btree_container &y) {
return !(y < x);
}
friend bool operator>=(const btree_container &x, const btree_container &y) {
return !(x < y);
}
// The allocator used by the btree.
allocator_type get_allocator() const { return tree_.get_allocator(); }
// The key comparator used by the btree.
key_compare key_comp() const { return tree_.key_comp(); }
value_compare value_comp() const { return tree_.value_comp(); }
// Support absl::Hash.
template <typename State>
friend State AbslHashValue(State h, const btree_container &b) {
for (const auto &v : b) {
h = State::combine(std::move(h), v);
}
return State::combine(std::move(h), b.size());
}
protected:
Tree tree_;
};
// A common base class for btree_set and btree_map.
template <typename Tree>
class btree_set_container : public btree_container<Tree> {
using super_type = btree_container<Tree>;
using params_type = typename Tree::params_type;
using init_type = typename params_type::init_type;
using is_key_compare_to = typename params_type::is_key_compare_to;
friend class BtreeNodePeer;
protected:
template <class K>
using key_arg = typename super_type::template key_arg<K>;
public:
using key_type = typename Tree::key_type;
using value_type = typename Tree::value_type;
using size_type = typename Tree::size_type;
using key_compare = typename Tree::key_compare;
using allocator_type = typename Tree::allocator_type;
using iterator = typename Tree::iterator;
using const_iterator = typename Tree::const_iterator;
using node_type = typename super_type::node_type;
using insert_return_type = InsertReturnType<iterator, node_type>;
// Inherit constructors.
using super_type::super_type;
btree_set_container() {}
// Range constructors.
template <class InputIterator>
btree_set_container(InputIterator b, InputIterator e,
const key_compare &comp = key_compare(),
const allocator_type &alloc = allocator_type())
: super_type(comp, alloc) {
insert(b, e);
}
template <class InputIterator>
btree_set_container(InputIterator b, InputIterator e,
const allocator_type &alloc)
: btree_set_container(b, e, key_compare(), alloc) {}
// Initializer list constructors.
btree_set_container(std::initializer_list<init_type> init,
const key_compare &comp = key_compare(),
const allocator_type &alloc = allocator_type())
: btree_set_container(init.begin(), init.end(), comp, alloc) {}
btree_set_container(std::initializer_list<init_type> init,
const allocator_type &alloc)
: btree_set_container(init.begin(), init.end(), alloc) {}
// Insertion routines.
std::pair<iterator, bool> insert(const value_type &v) {
return this->tree_.insert_unique(params_type::key(v), v);
}
std::pair<iterator, bool> insert(value_type &&v) {
return this->tree_.insert_unique(params_type::key(v), std::move(v));
}
template <typename... Args>
std::pair<iterator, bool> emplace(Args &&... args) {
init_type v(std::forward<Args>(args)...);
return this->tree_.insert_unique(params_type::key(v), std::move(v));
}
iterator insert(const_iterator hint, const value_type &v) {
return this->tree_
.insert_hint_unique(iterator(hint), params_type::key(v), v)
.first;
}
iterator insert(const_iterator hint, value_type &&v) {
return this->tree_
.insert_hint_unique(iterator(hint), params_type::key(v), std::move(v))
.first;
}
template <typename... Args>
iterator emplace_hint(const_iterator hint, Args &&... args) {
init_type v(std::forward<Args>(args)...);
return this->tree_
.insert_hint_unique(iterator(hint), params_type::key(v), std::move(v))
.first;
}
template <typename InputIterator>
void insert(InputIterator b, InputIterator e) {
this->tree_.insert_iterator_unique(b, e, 0);
}
void insert(std::initializer_list<init_type> init) {
this->tree_.insert_iterator_unique(init.begin(), init.end(), 0);
}
insert_return_type insert(node_type &&node) {
if (!node) return {this->end(), false, node_type()};
std::pair<iterator, bool> res =
this->tree_.insert_unique(params_type::key(CommonAccess::GetSlot(node)),
CommonAccess::GetSlot(node));
if (res.second) {
CommonAccess::Destroy(&node);
return {res.first, true, node_type()};
} else {
return {res.first, false, std::move(node)};
}
}
iterator insert(const_iterator hint, node_type &&node) {
if (!node) return this->end();
std::pair<iterator, bool> res = this->tree_.insert_hint_unique(
iterator(hint), params_type::key(CommonAccess::GetSlot(node)),
CommonAccess::GetSlot(node));
if (res.second) CommonAccess::Destroy(&node);
return res.first;
}
// Node extraction routines.
// TODO(ezb): when the comparator is heterogeneous and has different
// equivalence classes for different lookup types, we should extract the first
// equivalent value if there are multiple.
template <typename K = key_type>
node_type extract(const key_arg<K> &key) {
auto it = this->find(key);
return it == this->end() ? node_type() : extract(it);
}
using super_type::extract;
// Merge routines.
// Moves elements from `src` into `this`. If the element already exists in
// `this`, it is left unmodified in `src`.
template <
typename T,
typename absl::enable_if_t<
absl::conjunction<
std::is_same<value_type, typename T::value_type>,
std::is_same<allocator_type, typename T::allocator_type>,
std::is_same<typename params_type::is_map_container,
typename T::params_type::is_map_container>>::value,
int> = 0>
void merge(btree_container<T> &src) { // NOLINT
for (auto src_it = src.begin(); src_it != src.end();) {
if (insert(std::move(params_type::element(src_it.slot()))).second) {
src_it = src.erase(src_it);
} else {
++src_it;
}
}
}
template <
typename T,
typename absl::enable_if_t<
absl::conjunction<
std::is_same<value_type, typename T::value_type>,
std::is_same<allocator_type, typename T::allocator_type>,
std::is_same<typename params_type::is_map_container,
typename T::params_type::is_map_container>>::value,
int> = 0>
void merge(btree_container<T> &&src) {
merge(src);
}
};
// Base class for btree_map.
template <typename Tree>
class btree_map_container : public btree_set_container<Tree> {
using super_type = btree_set_container<Tree>;
using params_type = typename Tree::params_type;
friend class BtreeNodePeer;
private:
template <class K>
using key_arg = typename super_type::template key_arg<K>;
public:
using key_type = typename Tree::key_type;
using mapped_type = typename params_type::mapped_type;
using value_type = typename Tree::value_type;
using key_compare = typename Tree::key_compare;
using allocator_type = typename Tree::allocator_type;
using iterator = typename Tree::iterator;
using const_iterator = typename Tree::const_iterator;
// Inherit constructors.
using super_type::super_type;
btree_map_container() {}
// Insertion routines.
// Note: the nullptr template arguments and extra `const M&` overloads allow
// for supporting bitfield arguments.
template <typename K = key_type, class M>
std::pair<iterator, bool> insert_or_assign(const key_arg<K> &k,
const M &obj) {
return insert_or_assign_impl(k, obj);
}
template <typename K = key_type, class M, K * = nullptr>
std::pair<iterator, bool> insert_or_assign(key_arg<K> &&k, const M &obj) {
return insert_or_assign_impl(std::forward<K>(k), obj);
}
template <typename K = key_type, class M, M * = nullptr>
std::pair<iterator, bool> insert_or_assign(const key_arg<K> &k, M &&obj) {
return insert_or_assign_impl(k, std::forward<M>(obj));
}
template <typename K = key_type, class M, K * = nullptr, M * = nullptr>
std::pair<iterator, bool> insert_or_assign(key_arg<K> &&k, M &&obj) {
return insert_or_assign_impl(std::forward<K>(k), std::forward<M>(obj));
}
template <typename K = key_type, class M>
iterator insert_or_assign(const_iterator hint, const key_arg<K> &k,
const M &obj) {
return insert_or_assign_hint_impl(hint, k, obj);
}
template <typename K = key_type, class M, K * = nullptr>
iterator insert_or_assign(const_iterator hint, key_arg<K> &&k, const M &obj) {
return insert_or_assign_hint_impl(hint, std::forward<K>(k), obj);
}
template <typename K = key_type, class M, M * = nullptr>
iterator insert_or_assign(const_iterator hint, const key_arg<K> &k, M &&obj) {
return insert_or_assign_hint_impl(hint, k, std::forward<M>(obj));
}
template <typename K = key_type, class M, K * = nullptr, M * = nullptr>
iterator insert_or_assign(const_iterator hint, key_arg<K> &&k, M &&obj) {
return insert_or_assign_hint_impl(hint, std::forward<K>(k),
std::forward<M>(obj));
}
template <typename K = key_type, typename... Args,
typename absl::enable_if_t<
!std::is_convertible<K, const_iterator>::value, int> = 0>
std::pair<iterator, bool> try_emplace(const key_arg<K> &k, Args &&... args) {
return try_emplace_impl(k, std::forward<Args>(args)...);
}
template <typename K = key_type, typename... Args,
typename absl::enable_if_t<
!std::is_convertible<K, const_iterator>::value, int> = 0>
std::pair<iterator, bool> try_emplace(key_arg<K> &&k, Args &&... args) {
return try_emplace_impl(std::forward<K>(k), std::forward<Args>(args)...);
}
template <typename K = key_type, typename... Args>
iterator try_emplace(const_iterator hint, const key_arg<K> &k,
Args &&... args) {
return try_emplace_hint_impl(hint, k, std::forward<Args>(args)...);
}
template <typename K = key_type, typename... Args>
iterator try_emplace(const_iterator hint, key_arg<K> &&k, Args &&... args) {
return try_emplace_hint_impl(hint, std::forward<K>(k),
std::forward<Args>(args)...);
}
template <typename K = key_type>
mapped_type &operator[](const key_arg<K> &k) {
return try_emplace(k).first->second;
}
template <typename K = key_type>
mapped_type &operator[](key_arg<K> &&k) {
return try_emplace(std::forward<K>(k)).first->second;
}
template <typename K = key_type>
mapped_type &at(const key_arg<K> &key) {
auto it = this->find(key);
if (it == this->end())
base_internal::ThrowStdOutOfRange("absl::btree_map::at");
return it->second;
}
template <typename K = key_type>
const mapped_type &at(const key_arg<K> &key) const {
auto it = this->find(key);
if (it == this->end())
base_internal::ThrowStdOutOfRange("absl::btree_map::at");
return it->second;
}
private:
// Note: when we call `std::forward<M>(obj)` twice, it's safe because
// insert_unique/insert_hint_unique are guaranteed to not consume `obj` when
// `ret.second` is false.
template <class K, class M>
std::pair<iterator, bool> insert_or_assign_impl(K &&k, M &&obj) {
const std::pair<iterator, bool> ret =
this->tree_.insert_unique(k, std::forward<K>(k), std::forward<M>(obj));
if (!ret.second) ret.first->second = std::forward<M>(obj);
return ret;
}
template <class K, class M>
iterator insert_or_assign_hint_impl(const_iterator hint, K &&k, M &&obj) {
const std::pair<iterator, bool> ret = this->tree_.insert_hint_unique(
iterator(hint), k, std::forward<K>(k), std::forward<M>(obj));
if (!ret.second) ret.first->second = std::forward<M>(obj);
return ret.first;
}
template <class K, class... Args>
std::pair<iterator, bool> try_emplace_impl(K &&k, Args &&... args) {
return this->tree_.insert_unique(
k, std::piecewise_construct, std::forward_as_tuple(std::forward<K>(k)),
std::forward_as_tuple(std::forward<Args>(args)...));
}
template <class K, class... Args>
iterator try_emplace_hint_impl(const_iterator hint, K &&k, Args &&... args) {
return this->tree_
.insert_hint_unique(iterator(hint), k, std::piecewise_construct,
std::forward_as_tuple(std::forward<K>(k)),
std::forward_as_tuple(std::forward<Args>(args)...))
.first;
}
};
// A common base class for btree_multiset and btree_multimap.
template <typename Tree>
class btree_multiset_container : public btree_container<Tree> {
using super_type = btree_container<Tree>;
using params_type = typename Tree::params_type;
using init_type = typename params_type::init_type;
using is_key_compare_to = typename params_type::is_key_compare_to;
template <class K>
using key_arg = typename super_type::template key_arg<K>;
public:
using key_type = typename Tree::key_type;
using value_type = typename Tree::value_type;
using size_type = typename Tree::size_type;
using key_compare = typename Tree::key_compare;
using allocator_type = typename Tree::allocator_type;
using iterator = typename Tree::iterator;
using const_iterator = typename Tree::const_iterator;
using node_type = typename super_type::node_type;
// Inherit constructors.
using super_type::super_type;
btree_multiset_container() {}
// Range constructors.
template <class InputIterator>
btree_multiset_container(InputIterator b, InputIterator e,
const key_compare &comp = key_compare(),
const allocator_type &alloc = allocator_type())
: super_type(comp, alloc) {
insert(b, e);
}
template <class InputIterator>
btree_multiset_container(InputIterator b, InputIterator e,
const allocator_type &alloc)
: btree_multiset_container(b, e, key_compare(), alloc) {}
// Initializer list constructors.
btree_multiset_container(std::initializer_list<init_type> init,
const key_compare &comp = key_compare(),
const allocator_type &alloc = allocator_type())
: btree_multiset_container(init.begin(), init.end(), comp, alloc) {}
btree_multiset_container(std::initializer_list<init_type> init,
const allocator_type &alloc)
: btree_multiset_container(init.begin(), init.end(), alloc) {}
// Insertion routines.
iterator insert(const value_type &v) { return this->tree_.insert_multi(v); }
iterator insert(value_type &&v) {
return this->tree_.insert_multi(std::move(v));
}
iterator insert(const_iterator hint, const value_type &v) {
return this->tree_.insert_hint_multi(iterator(hint), v);
}
iterator insert(const_iterator hint, value_type &&v) {
return this->tree_.insert_hint_multi(iterator(hint), std::move(v));
}
template <typename InputIterator>
void insert(InputIterator b, InputIterator e) {
this->tree_.insert_iterator_multi(b, e);
}
void insert(std::initializer_list<init_type> init) {
this->tree_.insert_iterator_multi(init.begin(), init.end());
}
template <typename... Args>
iterator emplace(Args &&... args) {
return this->tree_.insert_multi(init_type(std::forward<Args>(args)...));
}
template <typename... Args>
iterator emplace_hint(const_iterator hint, Args &&... args) {
return this->tree_.insert_hint_multi(
iterator(hint), init_type(std::forward<Args>(args)...));
}
iterator insert(node_type &&node) {
if (!node) return this->end();
iterator res =
this->tree_.insert_multi(params_type::key(CommonAccess::GetSlot(node)),
CommonAccess::GetSlot(node));
CommonAccess::Destroy(&node);
return res;
}
iterator insert(const_iterator hint, node_type &&node) {
if (!node) return this->end();
iterator res = this->tree_.insert_hint_multi(
iterator(hint),
std::move(params_type::element(CommonAccess::GetSlot(node))));
CommonAccess::Destroy(&node);
return res;
}
// Node extraction routines.
// TODO(ezb): we are supposed to extract the first equivalent key if there are
// multiple, but this isn't guaranteed to extract the first one.
template <typename K = key_type>
node_type extract(const key_arg<K> &key) {
auto it = this->find(key);
return it == this->end() ? node_type() : extract(it);
}
using super_type::extract;
// Merge routines.
// Moves all elements from `src` into `this`.
template <
typename T,
typename absl::enable_if_t<
absl::conjunction<
std::is_same<value_type, typename T::value_type>,
std::is_same<allocator_type, typename T::allocator_type>,
std::is_same<typename params_type::is_map_container,
typename T::params_type::is_map_container>>::value,
int> = 0>
void merge(btree_container<T> &src) { // NOLINT
for (auto src_it = src.begin(), end = src.end(); src_it != end; ++src_it) {
insert(std::move(params_type::element(src_it.slot())));
}
src.clear();
}
template <
typename T,
typename absl::enable_if_t<
absl::conjunction<
std::is_same<value_type, typename T::value_type>,
std::is_same<allocator_type, typename T::allocator_type>,
std::is_same<typename params_type::is_map_container,
typename T::params_type::is_map_container>>::value,
int> = 0>
void merge(btree_container<T> &&src) {
merge(src);
}
};
// A base class for btree_multimap.
template <typename Tree>
class btree_multimap_container : public btree_multiset_container<Tree> {
using super_type = btree_multiset_container<Tree>;
using params_type = typename Tree::params_type;
public:
using mapped_type = typename params_type::mapped_type;
// Inherit constructors.
using super_type::super_type;
btree_multimap_container() {}
};
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_INTERNAL_BTREE_CONTAINER_H_