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Diffstat (limited to 'src/leveldb/table/two_level_iterator.cc')
-rw-r--r--src/leveldb/table/two_level_iterator.cc91
1 files changed, 40 insertions, 51 deletions
diff --git a/src/leveldb/table/two_level_iterator.cc b/src/leveldb/table/two_level_iterator.cc
index 7822ebab9c..144790dd97 100644
--- a/src/leveldb/table/two_level_iterator.cc
+++ b/src/leveldb/table/two_level_iterator.cc
@@ -15,38 +15,33 @@ namespace {
typedef Iterator* (*BlockFunction)(void*, const ReadOptions&, const Slice&);
-class TwoLevelIterator: public Iterator {
+class TwoLevelIterator : public Iterator {
public:
- TwoLevelIterator(
- Iterator* index_iter,
- BlockFunction block_function,
- void* arg,
- const ReadOptions& options);
-
- virtual ~TwoLevelIterator();
-
- virtual void Seek(const Slice& target);
- virtual void SeekToFirst();
- virtual void SeekToLast();
- virtual void Next();
- virtual void Prev();
-
- virtual bool Valid() const {
- return data_iter_.Valid();
- }
- virtual Slice key() const {
+ TwoLevelIterator(Iterator* index_iter, BlockFunction block_function,
+ void* arg, const ReadOptions& options);
+
+ ~TwoLevelIterator() override;
+
+ void Seek(const Slice& target) override;
+ void SeekToFirst() override;
+ void SeekToLast() override;
+ void Next() override;
+ void Prev() override;
+
+ bool Valid() const override { return data_iter_.Valid(); }
+ Slice key() const override {
assert(Valid());
return data_iter_.key();
}
- virtual Slice value() const {
+ Slice value() const override {
assert(Valid());
return data_iter_.value();
}
- virtual Status status() const {
+ Status status() const override {
// It'd be nice if status() returned a const Status& instead of a Status
if (!index_iter_.status().ok()) {
return index_iter_.status();
- } else if (data_iter_.iter() != NULL && !data_iter_.status().ok()) {
+ } else if (data_iter_.iter() != nullptr && !data_iter_.status().ok()) {
return data_iter_.status();
} else {
return status_;
@@ -67,45 +62,41 @@ class TwoLevelIterator: public Iterator {
const ReadOptions options_;
Status status_;
IteratorWrapper index_iter_;
- IteratorWrapper data_iter_; // May be NULL
- // If data_iter_ is non-NULL, then "data_block_handle_" holds the
+ IteratorWrapper data_iter_; // May be nullptr
+ // If data_iter_ is non-null, then "data_block_handle_" holds the
// "index_value" passed to block_function_ to create the data_iter_.
std::string data_block_handle_;
};
-TwoLevelIterator::TwoLevelIterator(
- Iterator* index_iter,
- BlockFunction block_function,
- void* arg,
- const ReadOptions& options)
+TwoLevelIterator::TwoLevelIterator(Iterator* index_iter,
+ BlockFunction block_function, void* arg,
+ const ReadOptions& options)
: block_function_(block_function),
arg_(arg),
options_(options),
index_iter_(index_iter),
- data_iter_(NULL) {
-}
+ data_iter_(nullptr) {}
-TwoLevelIterator::~TwoLevelIterator() {
-}
+TwoLevelIterator::~TwoLevelIterator() = default;
void TwoLevelIterator::Seek(const Slice& target) {
index_iter_.Seek(target);
InitDataBlock();
- if (data_iter_.iter() != NULL) data_iter_.Seek(target);
+ if (data_iter_.iter() != nullptr) data_iter_.Seek(target);
SkipEmptyDataBlocksForward();
}
void TwoLevelIterator::SeekToFirst() {
index_iter_.SeekToFirst();
InitDataBlock();
- if (data_iter_.iter() != NULL) data_iter_.SeekToFirst();
+ if (data_iter_.iter() != nullptr) data_iter_.SeekToFirst();
SkipEmptyDataBlocksForward();
}
void TwoLevelIterator::SeekToLast() {
index_iter_.SeekToLast();
InitDataBlock();
- if (data_iter_.iter() != NULL) data_iter_.SeekToLast();
+ if (data_iter_.iter() != nullptr) data_iter_.SeekToLast();
SkipEmptyDataBlocksBackward();
}
@@ -121,44 +112,44 @@ void TwoLevelIterator::Prev() {
SkipEmptyDataBlocksBackward();
}
-
void TwoLevelIterator::SkipEmptyDataBlocksForward() {
- while (data_iter_.iter() == NULL || !data_iter_.Valid()) {
+ while (data_iter_.iter() == nullptr || !data_iter_.Valid()) {
// Move to next block
if (!index_iter_.Valid()) {
- SetDataIterator(NULL);
+ SetDataIterator(nullptr);
return;
}
index_iter_.Next();
InitDataBlock();
- if (data_iter_.iter() != NULL) data_iter_.SeekToFirst();
+ if (data_iter_.iter() != nullptr) data_iter_.SeekToFirst();
}
}
void TwoLevelIterator::SkipEmptyDataBlocksBackward() {
- while (data_iter_.iter() == NULL || !data_iter_.Valid()) {
+ while (data_iter_.iter() == nullptr || !data_iter_.Valid()) {
// Move to next block
if (!index_iter_.Valid()) {
- SetDataIterator(NULL);
+ SetDataIterator(nullptr);
return;
}
index_iter_.Prev();
InitDataBlock();
- if (data_iter_.iter() != NULL) data_iter_.SeekToLast();
+ if (data_iter_.iter() != nullptr) data_iter_.SeekToLast();
}
}
void TwoLevelIterator::SetDataIterator(Iterator* data_iter) {
- if (data_iter_.iter() != NULL) SaveError(data_iter_.status());
+ if (data_iter_.iter() != nullptr) SaveError(data_iter_.status());
data_iter_.Set(data_iter);
}
void TwoLevelIterator::InitDataBlock() {
if (!index_iter_.Valid()) {
- SetDataIterator(NULL);
+ SetDataIterator(nullptr);
} else {
Slice handle = index_iter_.value();
- if (data_iter_.iter() != NULL && handle.compare(data_block_handle_) == 0) {
+ if (data_iter_.iter() != nullptr &&
+ handle.compare(data_block_handle_) == 0) {
// data_iter_ is already constructed with this iterator, so
// no need to change anything
} else {
@@ -171,11 +162,9 @@ void TwoLevelIterator::InitDataBlock() {
} // namespace
-Iterator* NewTwoLevelIterator(
- Iterator* index_iter,
- BlockFunction block_function,
- void* arg,
- const ReadOptions& options) {
+Iterator* NewTwoLevelIterator(Iterator* index_iter,
+ BlockFunction block_function, void* arg,
+ const ReadOptions& options) {
return new TwoLevelIterator(index_iter, block_function, arg, options);
}