mirror of
https://github.com/facebook/rocksdb.git
synced 2024-11-26 16:30:56 +00:00
97265f5f14
Summary: List of changes: 1) Fix the snprintf() usage in cases where wrong variable was used to determine the output buffer size. 2) Remove unnecessary checks before calling delete operator. 3) Increase code correctness by using size_t type when getting vector's size. 4) Unify the coding style by removing namespace::std usage at the top of the file to confirm to the majority usage. 5) Fix various lint errors pointed out by 'arc lint'. Test Plan: Code review and build: git diff make clean make -j 32 commit-prereq arc lint Reviewers: kradhakrishnan, sdong, rven, anthony, yhchiang, igor Reviewed By: igor Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D51849
768 lines
23 KiB
C++
768 lines
23 KiB
C++
// Copyright (c) 2013, Facebook, Inc. All rights reserved.
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// This source code is licensed under the BSD-style license found in the
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// LICENSE file in the root directory of this source tree. An additional grant
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// of patent rights can be found in the PATENTS file in the same directory.
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#ifndef ROCKSDB_LITE
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#include "db/forward_iterator.h"
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#include <limits>
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#include <string>
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#include <utility>
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#include "db/job_context.h"
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#include "db/db_impl.h"
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#include "db/db_iter.h"
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#include "db/column_family.h"
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#include "rocksdb/env.h"
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#include "rocksdb/slice.h"
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#include "rocksdb/slice_transform.h"
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#include "table/merger.h"
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#include "db/dbformat.h"
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#include "util/sync_point.h"
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namespace rocksdb {
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// Usage:
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// LevelIterator iter;
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// iter.SetFileIndex(file_index);
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// iter.Seek(target);
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// iter.Next()
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class LevelIterator : public InternalIterator {
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public:
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LevelIterator(const ColumnFamilyData* const cfd,
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const ReadOptions& read_options,
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const std::vector<FileMetaData*>& files)
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: cfd_(cfd), read_options_(read_options), files_(files), valid_(false),
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file_index_(std::numeric_limits<uint32_t>::max()) {}
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void SetFileIndex(uint32_t file_index) {
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assert(file_index < files_.size());
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if (file_index != file_index_) {
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file_index_ = file_index;
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Reset();
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}
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valid_ = false;
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}
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void Reset() {
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assert(file_index_ < files_.size());
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file_iter_.reset(cfd_->table_cache()->NewIterator(
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read_options_, *(cfd_->soptions()), cfd_->internal_comparator(),
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files_[file_index_]->fd, nullptr /* table_reader_ptr */, nullptr,
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false));
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}
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void SeekToLast() override {
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status_ = Status::NotSupported("LevelIterator::SeekToLast()");
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valid_ = false;
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}
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void Prev() override {
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status_ = Status::NotSupported("LevelIterator::Prev()");
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valid_ = false;
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}
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bool Valid() const override {
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return valid_;
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}
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void SeekToFirst() override {
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SetFileIndex(0);
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file_iter_->SeekToFirst();
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valid_ = file_iter_->Valid();
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}
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void Seek(const Slice& internal_key) override {
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assert(file_iter_ != nullptr);
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file_iter_->Seek(internal_key);
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valid_ = file_iter_->Valid();
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}
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void Next() override {
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assert(valid_);
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file_iter_->Next();
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for (;;) {
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if (file_iter_->status().IsIncomplete() || file_iter_->Valid()) {
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valid_ = !file_iter_->status().IsIncomplete();
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return;
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}
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if (file_index_ + 1 >= files_.size()) {
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valid_ = false;
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return;
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}
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SetFileIndex(file_index_ + 1);
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file_iter_->SeekToFirst();
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}
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}
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Slice key() const override {
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assert(valid_);
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return file_iter_->key();
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}
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Slice value() const override {
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assert(valid_);
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return file_iter_->value();
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}
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Status status() const override {
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if (!status_.ok()) {
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return status_;
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} else if (file_iter_ && !file_iter_->status().ok()) {
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return file_iter_->status();
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}
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return Status::OK();
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}
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private:
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const ColumnFamilyData* const cfd_;
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const ReadOptions& read_options_;
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const std::vector<FileMetaData*>& files_;
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bool valid_;
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uint32_t file_index_;
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Status status_;
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std::unique_ptr<InternalIterator> file_iter_;
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};
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ForwardIterator::ForwardIterator(DBImpl* db, const ReadOptions& read_options,
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ColumnFamilyData* cfd,
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SuperVersion* current_sv)
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: db_(db),
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read_options_(read_options),
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cfd_(cfd),
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prefix_extractor_(cfd->ioptions()->prefix_extractor),
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user_comparator_(cfd->user_comparator()),
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immutable_min_heap_(MinIterComparator(&cfd_->internal_comparator())),
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sv_(current_sv),
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mutable_iter_(nullptr),
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current_(nullptr),
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valid_(false),
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status_(Status::OK()),
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immutable_status_(Status::OK()),
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has_iter_trimmed_for_upper_bound_(false),
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current_over_upper_bound_(false),
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is_prev_set_(false),
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is_prev_inclusive_(false) {
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if (sv_) {
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RebuildIterators(false);
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}
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}
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ForwardIterator::~ForwardIterator() {
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Cleanup(true);
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}
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void ForwardIterator::SVCleanup() {
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if (sv_ != nullptr && sv_->Unref()) {
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// Job id == 0 means that this is not our background process, but rather
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// user thread
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JobContext job_context(0);
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db_->mutex_.Lock();
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sv_->Cleanup();
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db_->FindObsoleteFiles(&job_context, false, true);
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db_->mutex_.Unlock();
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delete sv_;
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if (job_context.HaveSomethingToDelete()) {
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db_->PurgeObsoleteFiles(job_context);
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}
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job_context.Clean();
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}
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}
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void ForwardIterator::Cleanup(bool release_sv) {
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if (mutable_iter_ != nullptr) {
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mutable_iter_->~InternalIterator();
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}
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for (auto* m : imm_iters_) {
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m->~InternalIterator();
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}
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imm_iters_.clear();
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for (auto* f : l0_iters_) {
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delete f;
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}
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l0_iters_.clear();
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for (auto* l : level_iters_) {
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delete l;
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}
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level_iters_.clear();
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if (release_sv) {
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SVCleanup();
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}
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}
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bool ForwardIterator::Valid() const {
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// See UpdateCurrent().
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return valid_ ? !current_over_upper_bound_ : false;
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}
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void ForwardIterator::SeekToFirst() {
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if (sv_ == nullptr) {
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RebuildIterators(true);
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} else if (sv_->version_number != cfd_->GetSuperVersionNumber()) {
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RenewIterators();
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} else if (immutable_status_.IsIncomplete()) {
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ResetIncompleteIterators();
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}
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SeekInternal(Slice(), true);
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}
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bool ForwardIterator::IsOverUpperBound(const Slice& internal_key) const {
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return !(read_options_.iterate_upper_bound == nullptr ||
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cfd_->internal_comparator().user_comparator()->Compare(
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ExtractUserKey(internal_key),
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*read_options_.iterate_upper_bound) < 0);
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}
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void ForwardIterator::Seek(const Slice& internal_key) {
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if (IsOverUpperBound(internal_key)) {
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valid_ = false;
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}
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if (sv_ == nullptr) {
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RebuildIterators(true);
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} else if (sv_->version_number != cfd_->GetSuperVersionNumber()) {
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RenewIterators();
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} else if (immutable_status_.IsIncomplete()) {
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ResetIncompleteIterators();
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}
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SeekInternal(internal_key, false);
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}
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void ForwardIterator::SeekInternal(const Slice& internal_key,
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bool seek_to_first) {
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assert(mutable_iter_);
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// mutable
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seek_to_first ? mutable_iter_->SeekToFirst() :
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mutable_iter_->Seek(internal_key);
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// immutable
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// TODO(ljin): NeedToSeekImmutable has negative impact on performance
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// if it turns to need to seek immutable often. We probably want to have
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// an option to turn it off.
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if (seek_to_first || NeedToSeekImmutable(internal_key)) {
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immutable_status_ = Status::OK();
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if ((has_iter_trimmed_for_upper_bound_) &&
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(cfd_->internal_comparator().InternalKeyComparator::Compare(
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prev_key_.GetKey(), internal_key) > 0)) {
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// Some iterators are trimmed. Need to rebuild.
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RebuildIterators(true);
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// Already seeked mutable iter, so seek again
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seek_to_first ? mutable_iter_->SeekToFirst()
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: mutable_iter_->Seek(internal_key);
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}
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{
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auto tmp = MinIterHeap(MinIterComparator(&cfd_->internal_comparator()));
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immutable_min_heap_.swap(tmp);
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}
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for (size_t i = 0; i < imm_iters_.size(); i++) {
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auto* m = imm_iters_[i];
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seek_to_first ? m->SeekToFirst() : m->Seek(internal_key);
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if (!m->status().ok()) {
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immutable_status_ = m->status();
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} else if (m->Valid()) {
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immutable_min_heap_.push(m);
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}
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}
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Slice user_key;
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if (!seek_to_first) {
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user_key = ExtractUserKey(internal_key);
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}
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const VersionStorageInfo* vstorage = sv_->current->storage_info();
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const std::vector<FileMetaData*>& l0 = vstorage->LevelFiles(0);
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for (size_t i = 0; i < l0.size(); ++i) {
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if (!l0_iters_[i]) {
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continue;
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}
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if (seek_to_first) {
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l0_iters_[i]->SeekToFirst();
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} else {
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// If the target key passes over the larget key, we are sure Next()
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// won't go over this file.
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if (user_comparator_->Compare(user_key,
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l0[i]->largest.user_key()) > 0) {
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if (read_options_.iterate_upper_bound != nullptr) {
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has_iter_trimmed_for_upper_bound_ = true;
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delete l0_iters_[i];
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l0_iters_[i] = nullptr;
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}
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continue;
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}
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l0_iters_[i]->Seek(internal_key);
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}
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if (!l0_iters_[i]->status().ok()) {
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immutable_status_ = l0_iters_[i]->status();
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} else if (l0_iters_[i]->Valid()) {
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if (!IsOverUpperBound(l0_iters_[i]->key())) {
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immutable_min_heap_.push(l0_iters_[i]);
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} else {
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has_iter_trimmed_for_upper_bound_ = true;
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delete l0_iters_[i];
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l0_iters_[i] = nullptr;
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}
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}
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}
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int32_t search_left_bound = 0;
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int32_t search_right_bound = FileIndexer::kLevelMaxIndex;
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for (int32_t level = 1; level < vstorage->num_levels(); ++level) {
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const std::vector<FileMetaData*>& level_files =
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vstorage->LevelFiles(level);
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if (level_files.empty()) {
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search_left_bound = 0;
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search_right_bound = FileIndexer::kLevelMaxIndex;
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continue;
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}
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if (level_iters_[level - 1] == nullptr) {
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continue;
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}
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uint32_t f_idx = 0;
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const auto& indexer = vstorage->file_indexer();
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if (!seek_to_first) {
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if (search_left_bound == search_right_bound) {
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f_idx = search_left_bound;
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} else if (search_left_bound < search_right_bound) {
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f_idx =
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FindFileInRange(level_files, internal_key, search_left_bound,
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search_right_bound == FileIndexer::kLevelMaxIndex
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? static_cast<uint32_t>(level_files.size())
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: search_right_bound);
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} else {
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// search_left_bound > search_right_bound
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// There are only 2 cases this can happen:
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// (1) target key is smaller than left most file
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// (2) target key is larger than right most file
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assert(search_left_bound == (int32_t)level_files.size() ||
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search_right_bound == -1);
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if (search_right_bound == -1) {
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assert(search_left_bound == 0);
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f_idx = 0;
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} else {
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indexer.GetNextLevelIndex(
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level, level_files.size() - 1,
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1, 1, &search_left_bound, &search_right_bound);
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continue;
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}
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}
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// Prepare hints for the next level
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if (f_idx < level_files.size()) {
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int cmp_smallest = user_comparator_->Compare(
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user_key, level_files[f_idx]->smallest.user_key());
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assert(user_comparator_->Compare(
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user_key, level_files[f_idx]->largest.user_key()) <= 0);
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indexer.GetNextLevelIndex(level, f_idx, cmp_smallest, -1,
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&search_left_bound, &search_right_bound);
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} else {
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indexer.GetNextLevelIndex(
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level, level_files.size() - 1,
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1, 1, &search_left_bound, &search_right_bound);
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}
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}
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// Seek
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if (f_idx < level_files.size()) {
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level_iters_[level - 1]->SetFileIndex(f_idx);
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seek_to_first ? level_iters_[level - 1]->SeekToFirst() :
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level_iters_[level - 1]->Seek(internal_key);
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if (!level_iters_[level - 1]->status().ok()) {
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immutable_status_ = level_iters_[level - 1]->status();
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} else if (level_iters_[level - 1]->Valid()) {
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if (!IsOverUpperBound(level_iters_[level - 1]->key())) {
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immutable_min_heap_.push(level_iters_[level - 1]);
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} else {
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// Nothing in this level is interesting. Remove.
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has_iter_trimmed_for_upper_bound_ = true;
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delete level_iters_[level - 1];
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level_iters_[level - 1] = nullptr;
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}
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}
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}
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}
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if (seek_to_first) {
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is_prev_set_ = false;
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} else {
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prev_key_.SetKey(internal_key);
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is_prev_set_ = true;
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is_prev_inclusive_ = true;
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}
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TEST_SYNC_POINT_CALLBACK("ForwardIterator::SeekInternal:Immutable", this);
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} else if (current_ && current_ != mutable_iter_) {
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// current_ is one of immutable iterators, push it back to the heap
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immutable_min_heap_.push(current_);
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}
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UpdateCurrent();
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TEST_SYNC_POINT_CALLBACK("ForwardIterator::SeekInternal:Return", this);
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}
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void ForwardIterator::Next() {
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assert(valid_);
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bool update_prev_key = false;
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if (sv_ == nullptr ||
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sv_->version_number != cfd_->GetSuperVersionNumber()) {
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std::string current_key = key().ToString();
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Slice old_key(current_key.data(), current_key.size());
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if (sv_ == nullptr) {
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RebuildIterators(true);
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} else {
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RenewIterators();
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}
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SeekInternal(old_key, false);
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if (!valid_ || key().compare(old_key) != 0) {
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return;
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}
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} else if (current_ != mutable_iter_) {
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// It is going to advance immutable iterator
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if (is_prev_set_ && prefix_extractor_) {
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// advance prev_key_ to current_ only if they share the same prefix
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update_prev_key =
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prefix_extractor_->Transform(prev_key_.GetKey()).compare(
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prefix_extractor_->Transform(current_->key())) == 0;
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} else {
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update_prev_key = true;
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}
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if (update_prev_key) {
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prev_key_.SetKey(current_->key());
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is_prev_set_ = true;
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is_prev_inclusive_ = false;
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}
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}
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current_->Next();
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if (current_ != mutable_iter_) {
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if (!current_->status().ok()) {
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immutable_status_ = current_->status();
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} else if ((current_->Valid()) && (!IsOverUpperBound(current_->key()))) {
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immutable_min_heap_.push(current_);
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} else {
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if ((current_->Valid()) && (IsOverUpperBound(current_->key()))) {
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// remove the current iterator
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DeleteCurrentIter();
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current_ = nullptr;
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}
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if (update_prev_key) {
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mutable_iter_->Seek(prev_key_.GetKey());
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}
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}
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}
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UpdateCurrent();
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TEST_SYNC_POINT_CALLBACK("ForwardIterator::Next:Return", this);
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}
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Slice ForwardIterator::key() const {
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assert(valid_);
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return current_->key();
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}
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Slice ForwardIterator::value() const {
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assert(valid_);
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return current_->value();
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}
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Status ForwardIterator::status() const {
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if (!status_.ok()) {
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return status_;
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} else if (!mutable_iter_->status().ok()) {
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return mutable_iter_->status();
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}
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return immutable_status_;
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}
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void ForwardIterator::RebuildIterators(bool refresh_sv) {
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// Clean up
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Cleanup(refresh_sv);
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if (refresh_sv) {
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// New
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sv_ = cfd_->GetReferencedSuperVersion(&(db_->mutex_));
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}
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mutable_iter_ = sv_->mem->NewIterator(read_options_, &arena_);
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sv_->imm->AddIterators(read_options_, &imm_iters_, &arena_);
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has_iter_trimmed_for_upper_bound_ = false;
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const auto* vstorage = sv_->current->storage_info();
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const auto& l0_files = vstorage->LevelFiles(0);
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l0_iters_.reserve(l0_files.size());
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for (const auto* l0 : l0_files) {
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if ((read_options_.iterate_upper_bound != nullptr) &&
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cfd_->internal_comparator().user_comparator()->Compare(
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l0->smallest.user_key(), *read_options_.iterate_upper_bound) > 0) {
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has_iter_trimmed_for_upper_bound_ = true;
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l0_iters_.push_back(nullptr);
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continue;
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}
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l0_iters_.push_back(cfd_->table_cache()->NewIterator(
|
|
read_options_, *cfd_->soptions(), cfd_->internal_comparator(), l0->fd));
|
|
}
|
|
BuildLevelIterators(vstorage);
|
|
current_ = nullptr;
|
|
is_prev_set_ = false;
|
|
}
|
|
|
|
void ForwardIterator::RenewIterators() {
|
|
SuperVersion* svnew;
|
|
assert(sv_);
|
|
svnew = cfd_->GetReferencedSuperVersion(&(db_->mutex_));
|
|
|
|
if (mutable_iter_ != nullptr) {
|
|
mutable_iter_->~InternalIterator();
|
|
}
|
|
for (auto* m : imm_iters_) {
|
|
m->~InternalIterator();
|
|
}
|
|
imm_iters_.clear();
|
|
|
|
mutable_iter_ = svnew->mem->NewIterator(read_options_, &arena_);
|
|
svnew->imm->AddIterators(read_options_, &imm_iters_, &arena_);
|
|
|
|
const auto* vstorage = sv_->current->storage_info();
|
|
const auto& l0_files = vstorage->LevelFiles(0);
|
|
const auto* vstorage_new = svnew->current->storage_info();
|
|
const auto& l0_files_new = vstorage_new->LevelFiles(0);
|
|
size_t iold, inew;
|
|
bool found;
|
|
std::vector<InternalIterator*> l0_iters_new;
|
|
l0_iters_new.reserve(l0_files_new.size());
|
|
|
|
for (inew = 0; inew < l0_files_new.size(); inew++) {
|
|
found = false;
|
|
for (iold = 0; iold < l0_files.size(); iold++) {
|
|
if (l0_files[iold] == l0_files_new[inew]) {
|
|
found = true;
|
|
break;
|
|
}
|
|
}
|
|
if (found) {
|
|
if (l0_iters_[iold] == nullptr) {
|
|
l0_iters_new.push_back(nullptr);
|
|
TEST_SYNC_POINT_CALLBACK("ForwardIterator::RenewIterators:Null", this);
|
|
} else {
|
|
l0_iters_new.push_back(l0_iters_[iold]);
|
|
l0_iters_[iold] = nullptr;
|
|
TEST_SYNC_POINT_CALLBACK("ForwardIterator::RenewIterators:Copy", this);
|
|
}
|
|
continue;
|
|
}
|
|
l0_iters_new.push_back(cfd_->table_cache()->NewIterator(
|
|
read_options_, *cfd_->soptions(), cfd_->internal_comparator(),
|
|
l0_files_new[inew]->fd));
|
|
}
|
|
|
|
for (auto* f : l0_iters_) {
|
|
delete f;
|
|
}
|
|
l0_iters_.clear();
|
|
l0_iters_ = l0_iters_new;
|
|
|
|
for (auto* l : level_iters_) {
|
|
delete l;
|
|
}
|
|
level_iters_.clear();
|
|
BuildLevelIterators(vstorage_new);
|
|
current_ = nullptr;
|
|
is_prev_set_ = false;
|
|
SVCleanup();
|
|
sv_ = svnew;
|
|
}
|
|
|
|
void ForwardIterator::BuildLevelIterators(const VersionStorageInfo* vstorage) {
|
|
level_iters_.reserve(vstorage->num_levels() - 1);
|
|
for (int32_t level = 1; level < vstorage->num_levels(); ++level) {
|
|
const auto& level_files = vstorage->LevelFiles(level);
|
|
if ((level_files.empty()) ||
|
|
((read_options_.iterate_upper_bound != nullptr) &&
|
|
(user_comparator_->Compare(*read_options_.iterate_upper_bound,
|
|
level_files[0]->smallest.user_key()) <
|
|
0))) {
|
|
level_iters_.push_back(nullptr);
|
|
if (!level_files.empty()) {
|
|
has_iter_trimmed_for_upper_bound_ = true;
|
|
}
|
|
} else {
|
|
level_iters_.push_back(
|
|
new LevelIterator(cfd_, read_options_, level_files));
|
|
}
|
|
}
|
|
}
|
|
|
|
void ForwardIterator::ResetIncompleteIterators() {
|
|
const auto& l0_files = sv_->current->storage_info()->LevelFiles(0);
|
|
for (size_t i = 0; i < l0_iters_.size(); ++i) {
|
|
assert(i < l0_files.size());
|
|
if (!l0_iters_[i] || !l0_iters_[i]->status().IsIncomplete()) {
|
|
continue;
|
|
}
|
|
delete l0_iters_[i];
|
|
l0_iters_[i] = cfd_->table_cache()->NewIterator(
|
|
read_options_, *cfd_->soptions(), cfd_->internal_comparator(),
|
|
l0_files[i]->fd);
|
|
}
|
|
|
|
for (auto* level_iter : level_iters_) {
|
|
if (level_iter && level_iter->status().IsIncomplete()) {
|
|
level_iter->Reset();
|
|
}
|
|
}
|
|
|
|
current_ = nullptr;
|
|
is_prev_set_ = false;
|
|
}
|
|
|
|
void ForwardIterator::UpdateCurrent() {
|
|
if (immutable_min_heap_.empty() && !mutable_iter_->Valid()) {
|
|
current_ = nullptr;
|
|
} else if (immutable_min_heap_.empty()) {
|
|
current_ = mutable_iter_;
|
|
} else if (!mutable_iter_->Valid()) {
|
|
current_ = immutable_min_heap_.top();
|
|
immutable_min_heap_.pop();
|
|
} else {
|
|
current_ = immutable_min_heap_.top();
|
|
assert(current_ != nullptr);
|
|
assert(current_->Valid());
|
|
int cmp = cfd_->internal_comparator().InternalKeyComparator::Compare(
|
|
mutable_iter_->key(), current_->key());
|
|
assert(cmp != 0);
|
|
if (cmp > 0) {
|
|
immutable_min_heap_.pop();
|
|
} else {
|
|
current_ = mutable_iter_;
|
|
}
|
|
}
|
|
valid_ = (current_ != nullptr);
|
|
if (!status_.ok()) {
|
|
status_ = Status::OK();
|
|
}
|
|
|
|
// Upper bound doesn't apply to the memtable iterator. We want Valid() to
|
|
// return false when all iterators are over iterate_upper_bound, but can't
|
|
// just set valid_ to false, as that would effectively disable the tailing
|
|
// optimization (Seek() would be called on all immutable iterators regardless
|
|
// of whether the target key is greater than prev_key_).
|
|
current_over_upper_bound_ = valid_ && IsOverUpperBound(current_->key());
|
|
}
|
|
|
|
bool ForwardIterator::NeedToSeekImmutable(const Slice& target) {
|
|
// We maintain the interval (prev_key_, immutable_min_heap_.top()->key())
|
|
// such that there are no records with keys within that range in
|
|
// immutable_min_heap_. Since immutable structures (SST files and immutable
|
|
// memtables) can't change in this version, we don't need to do a seek if
|
|
// 'target' belongs to that interval (immutable_min_heap_.top() is already
|
|
// at the correct position).
|
|
|
|
if (!valid_ || !current_ || !is_prev_set_ || !immutable_status_.ok()) {
|
|
return true;
|
|
}
|
|
Slice prev_key = prev_key_.GetKey();
|
|
if (prefix_extractor_ && prefix_extractor_->Transform(target).compare(
|
|
prefix_extractor_->Transform(prev_key)) != 0) {
|
|
return true;
|
|
}
|
|
if (cfd_->internal_comparator().InternalKeyComparator::Compare(
|
|
prev_key, target) >= (is_prev_inclusive_ ? 1 : 0)) {
|
|
return true;
|
|
}
|
|
|
|
if (immutable_min_heap_.empty() && current_ == mutable_iter_) {
|
|
// Nothing to seek on.
|
|
return false;
|
|
}
|
|
if (cfd_->internal_comparator().InternalKeyComparator::Compare(
|
|
target, current_ == mutable_iter_ ? immutable_min_heap_.top()->key()
|
|
: current_->key()) > 0) {
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
void ForwardIterator::DeleteCurrentIter() {
|
|
const VersionStorageInfo* vstorage = sv_->current->storage_info();
|
|
const std::vector<FileMetaData*>& l0 = vstorage->LevelFiles(0);
|
|
for (size_t i = 0; i < l0.size(); ++i) {
|
|
if (!l0_iters_[i]) {
|
|
continue;
|
|
}
|
|
if (l0_iters_[i] == current_) {
|
|
has_iter_trimmed_for_upper_bound_ = true;
|
|
delete l0_iters_[i];
|
|
l0_iters_[i] = nullptr;
|
|
return;
|
|
}
|
|
}
|
|
|
|
for (int32_t level = 1; level < vstorage->num_levels(); ++level) {
|
|
if (level_iters_[level - 1] == nullptr) {
|
|
continue;
|
|
}
|
|
if (level_iters_[level - 1] == current_) {
|
|
has_iter_trimmed_for_upper_bound_ = true;
|
|
delete level_iters_[level - 1];
|
|
level_iters_[level - 1] = nullptr;
|
|
}
|
|
}
|
|
}
|
|
|
|
bool ForwardIterator::TEST_CheckDeletedIters(int* pdeleted_iters,
|
|
int* pnum_iters) {
|
|
bool retval = false;
|
|
int deleted_iters = 0;
|
|
int num_iters = 0;
|
|
|
|
const VersionStorageInfo* vstorage = sv_->current->storage_info();
|
|
const std::vector<FileMetaData*>& l0 = vstorage->LevelFiles(0);
|
|
for (size_t i = 0; i < l0.size(); ++i) {
|
|
if (!l0_iters_[i]) {
|
|
retval = true;
|
|
deleted_iters++;
|
|
} else {
|
|
num_iters++;
|
|
}
|
|
}
|
|
|
|
for (int32_t level = 1; level < vstorage->num_levels(); ++level) {
|
|
if ((level_iters_[level - 1] == nullptr) &&
|
|
(!vstorage->LevelFiles(level).empty())) {
|
|
retval = true;
|
|
deleted_iters++;
|
|
} else if (!vstorage->LevelFiles(level).empty()) {
|
|
num_iters++;
|
|
}
|
|
}
|
|
if ((!retval) && num_iters <= 1) {
|
|
retval = true;
|
|
}
|
|
if (pdeleted_iters) {
|
|
*pdeleted_iters = deleted_iters;
|
|
}
|
|
if (pnum_iters) {
|
|
*pnum_iters = num_iters;
|
|
}
|
|
return retval;
|
|
}
|
|
|
|
uint32_t ForwardIterator::FindFileInRange(
|
|
const std::vector<FileMetaData*>& files, const Slice& internal_key,
|
|
uint32_t left, uint32_t right) {
|
|
while (left < right) {
|
|
uint32_t mid = (left + right) / 2;
|
|
const FileMetaData* f = files[mid];
|
|
if (cfd_->internal_comparator().InternalKeyComparator::Compare(
|
|
f->largest.Encode(), internal_key) < 0) {
|
|
// Key at "mid.largest" is < "target". Therefore all
|
|
// files at or before "mid" are uninteresting.
|
|
left = mid + 1;
|
|
} else {
|
|
// Key at "mid.largest" is >= "target". Therefore all files
|
|
// after "mid" are uninteresting.
|
|
right = mid;
|
|
}
|
|
}
|
|
return right;
|
|
}
|
|
|
|
} // namespace rocksdb
|
|
|
|
#endif // ROCKSDB_LITE
|