mindspore2022/mindspore/ccsrc/minddata/dataset/util/auto_index.h

101 lines
3.0 KiB
C++

/**
* Copyright 2019 Huawei Technologies Co., Ltd
*
* 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
*
* http://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 MINDSPORE_CCSRC_MINDDATA_DATASET_UTIL_AUTO_INDEX_H_
#define MINDSPORE_CCSRC_MINDDATA_DATASET_UTIL_AUTO_INDEX_H_
#include <atomic>
#include <functional>
#include <memory>
#include <utility>
#include <vector>
#include "minddata/dataset/util/btree.h"
#include "minddata/dataset/util/system_pool.h"
namespace mindspore {
namespace dataset {
/// This is a B+ tree with generated int64_t value as key.
/// Use minKey() function to query the min key.
/// Use maxKey() function to query the max key.
/// @tparam T
template <typename V, typename A = std::allocator<V>, typename T = BPlusTreeTraits>
class AutoIndexObj : public BPlusTree<int64_t, V, A, std::less<int64_t>, T> {
public:
using my_tree = BPlusTree<int64_t, V, A, std::less<int64_t>, T>;
using key_type = typename my_tree::key_type;
using value_type = typename my_tree::value_type;
AutoIndexObj() : my_tree::BPlusTree(), inx_(kMinKey) {}
explicit AutoIndexObj(const Allocator<V> &alloc) : my_tree::BPlusTree(alloc), inx_(kMinKey) {}
~AutoIndexObj() = default;
// Insert an object into the tree.
// @param val
// @return
Status insert(const value_type &val, key_type *key = nullptr) {
key_type my_inx = inx_.fetch_add(1);
if (key != nullptr) {
*key = my_inx;
}
return my_tree::DoInsert(my_inx, val);
}
Status insert(std::unique_ptr<value_type> &&val, key_type *key = nullptr) {
key_type my_inx = inx_.fetch_add(1);
if (key != nullptr) {
*key = my_inx;
}
return my_tree::DoInsert(my_inx, std::move(val));
}
// Insert a vector of objects into the tree.
// @param v
// @return
Status insert(std::vector<value_type> v) {
uint64_t num_ele = v.size();
if (num_ele > 0) {
// reserve a range of keys rather than getting it one by one.
key_type my_inx = inx_.fetch_add(num_ele);
for (uint64_t i = 0; i < num_ele; i++) {
RETURN_IF_NOT_OK(my_tree::DoInsert(my_inx + i, v.at(i)));
}
}
return Status::OK();
}
// @return the minimum key
key_type min_key() const {
auto it = this->cbegin();
return it.key();
}
// @return the maximum key
key_type max_key() const {
auto it = this->cend();
--it;
return it.key();
}
private:
static constexpr key_type kMinKey = 0;
std::atomic<key_type> inx_;
};
} // namespace dataset
} // namespace mindspore
#endif // MINDSPORE_CCSRC_MINDDATA_DATASET_UTIL_AUTO_INDEX_H_