rocksdb/utilities/write_batch_with_index/write_batch_with_index.cc
Mike Kolupaev 8bf555f487 Change and clarify the relationship between Valid(), status() and Seek*() for all iterators. Also fix some bugs
Summary:
Before this PR, Iterator/InternalIterator may simultaneously have non-ok status() and Valid() = true. That state means that the last operation failed, but the iterator is nevertheless positioned on some unspecified record. Likely intended uses of that are:
 * If some sst files are corrupted, a normal iterator can be used to read the data from files that are not corrupted.
 * When using read_tier = kBlockCacheTier, read the data that's in block cache, skipping over the data that is not.

However, this behavior wasn't documented well (and until recently the wiki on github had misleading incorrect information). In the code there's a lot of confusion about the relationship between status() and Valid(), and about whether Seek()/SeekToLast()/etc reset the status or not. There were a number of bugs caused by this confusion, both inside rocksdb and in the code that uses rocksdb (including ours).

This PR changes the convention to:
 * If status() is not ok, Valid() always returns false.
 * Any seek operation resets status. (Before the PR, it depended on iterator type and on particular error.)

This does sacrifice the two use cases listed above, but siying said it's ok.

Overview of the changes:
 * A commit that adds missing status checks in MergingIterator. This fixes a bug that actually affects us, and we need it fixed. `DBIteratorTest.NonBlockingIterationBugRepro` explains the scenario.
 * Changes to lots of iterator types to make all of them conform to the new convention. Some bug fixes along the way. By far the biggest changes are in DBIter, which is a big messy piece of code; I tried to make it less big and messy but mostly failed.
 * A stress-test for DBIter, to gain some confidence that I didn't break it. It does a few million random operations on the iterator, while occasionally modifying the underlying data (like ForwardIterator does) and occasionally returning non-ok status from internal iterator.

To find the iterator types that needed changes I searched for "public .*Iterator" in the code. Here's an overview of all 27 iterator types:

Iterators that didn't need changes:
 * status() is always ok(), or Valid() is always false: MemTableIterator, ModelIter, TestIterator, KVIter (2 classes with this name anonymous namespaces), LoggingForwardVectorIterator, VectorIterator, MockTableIterator, EmptyIterator, EmptyInternalIterator.
 * Thin wrappers that always pass through Valid() and status(): ArenaWrappedDBIter, TtlIterator, InternalIteratorFromIterator.

Iterators with changes (see inline comments for details):
 * DBIter - an overhaul:
    - It used to silently skip corrupted keys (`FindParseableKey()`), which seems dangerous. This PR makes it just stop immediately after encountering a corrupted key, just like it would for other kinds of corruption. Let me know if there was actually some deeper meaning in this behavior and I should put it back.
    - It had a few code paths silently discarding subiterator's status. The stress test caught a few.
    - The backwards iteration code path was expecting the internal iterator's set of keys to be immutable. It's probably always true in practice at the moment, since ForwardIterator doesn't support backwards iteration, but this PR fixes it anyway. See added DBIteratorTest.ReverseToForwardBug for an example.
    - Some parts of backwards iteration code path even did things like `assert(iter_->Valid())` after a seek, which is never a safe assumption.
    - It used to not reset status on seek for some types of errors.
    - Some simplifications and better comments.
    - Some things got more complicated from the added error handling. I'm open to ideas for how to make it nicer.
 * MergingIterator - check status after every operation on every subiterator, and in some places assert that valid subiterators have ok status.
 * ForwardIterator - changed to the new convention, also slightly simplified.
 * ForwardLevelIterator - fixed some bugs and simplified.
 * LevelIterator - simplified.
 * TwoLevelIterator - changed to the new convention. Also fixed a bug that would make SeekForPrev() sometimes silently ignore errors from first_level_iter_.
 * BlockBasedTableIterator - minor changes.
 * BlockIter - replaced `SetStatus()` with `Invalidate()` to make sure non-ok BlockIter is always invalid.
 * PlainTableIterator - some seeks used to not reset status.
 * CuckooTableIterator - tiny code cleanup.
 * ManagedIterator - fixed some bugs.
 * BaseDeltaIterator - changed to the new convention and fixed a bug.
 * BlobDBIterator - seeks used to not reset status.
 * KeyConvertingIterator - some small change.
Closes https://github.com/facebook/rocksdb/pull/3810

Differential Revision: D7888019

Pulled By: al13n321

fbshipit-source-id: 4aaf6d3421c545d16722a815b2fa2e7912bc851d
2018-05-17 02:56:56 -07:00

942 lines
29 KiB
C++

// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
#ifndef ROCKSDB_LITE
#include "rocksdb/utilities/write_batch_with_index.h"
#include <memory>
#include "db/column_family.h"
#include "db/db_impl.h"
#include "db/merge_context.h"
#include "db/merge_helper.h"
#include "memtable/skiplist.h"
#include "options/db_options.h"
#include "rocksdb/comparator.h"
#include "rocksdb/iterator.h"
#include "util/arena.h"
#include "util/cast_util.h"
#include "util/string_util.h"
#include "utilities/write_batch_with_index/write_batch_with_index_internal.h"
namespace rocksdb {
// when direction == forward
// * current_at_base_ <=> base_iterator > delta_iterator
// when direction == backwards
// * current_at_base_ <=> base_iterator < delta_iterator
// always:
// * equal_keys_ <=> base_iterator == delta_iterator
class BaseDeltaIterator : public Iterator {
public:
BaseDeltaIterator(Iterator* base_iterator, WBWIIterator* delta_iterator,
const Comparator* comparator)
: forward_(true),
current_at_base_(true),
equal_keys_(false),
status_(Status::OK()),
base_iterator_(base_iterator),
delta_iterator_(delta_iterator),
comparator_(comparator) {}
virtual ~BaseDeltaIterator() {}
bool Valid() const override {
return current_at_base_ ? BaseValid() : DeltaValid();
}
void SeekToFirst() override {
forward_ = true;
base_iterator_->SeekToFirst();
delta_iterator_->SeekToFirst();
UpdateCurrent();
}
void SeekToLast() override {
forward_ = false;
base_iterator_->SeekToLast();
delta_iterator_->SeekToLast();
UpdateCurrent();
}
void Seek(const Slice& k) override {
forward_ = true;
base_iterator_->Seek(k);
delta_iterator_->Seek(k);
UpdateCurrent();
}
void SeekForPrev(const Slice& k) override {
forward_ = false;
base_iterator_->SeekForPrev(k);
delta_iterator_->SeekForPrev(k);
UpdateCurrent();
}
void Next() override {
if (!Valid()) {
status_ = Status::NotSupported("Next() on invalid iterator");
return;
}
if (!forward_) {
// Need to change direction
// if our direction was backward and we're not equal, we have two states:
// * both iterators are valid: we're already in a good state (current
// shows to smaller)
// * only one iterator is valid: we need to advance that iterator
forward_ = true;
equal_keys_ = false;
if (!BaseValid()) {
assert(DeltaValid());
base_iterator_->SeekToFirst();
} else if (!DeltaValid()) {
delta_iterator_->SeekToFirst();
} else if (current_at_base_) {
// Change delta from larger than base to smaller
AdvanceDelta();
} else {
// Change base from larger than delta to smaller
AdvanceBase();
}
if (DeltaValid() && BaseValid()) {
if (comparator_->Equal(delta_iterator_->Entry().key,
base_iterator_->key())) {
equal_keys_ = true;
}
}
}
Advance();
}
void Prev() override {
if (!Valid()) {
status_ = Status::NotSupported("Prev() on invalid iterator");
return;
}
if (forward_) {
// Need to change direction
// if our direction was backward and we're not equal, we have two states:
// * both iterators are valid: we're already in a good state (current
// shows to smaller)
// * only one iterator is valid: we need to advance that iterator
forward_ = false;
equal_keys_ = false;
if (!BaseValid()) {
assert(DeltaValid());
base_iterator_->SeekToLast();
} else if (!DeltaValid()) {
delta_iterator_->SeekToLast();
} else if (current_at_base_) {
// Change delta from less advanced than base to more advanced
AdvanceDelta();
} else {
// Change base from less advanced than delta to more advanced
AdvanceBase();
}
if (DeltaValid() && BaseValid()) {
if (comparator_->Equal(delta_iterator_->Entry().key,
base_iterator_->key())) {
equal_keys_ = true;
}
}
}
Advance();
}
Slice key() const override {
return current_at_base_ ? base_iterator_->key()
: delta_iterator_->Entry().key;
}
Slice value() const override {
return current_at_base_ ? base_iterator_->value()
: delta_iterator_->Entry().value;
}
Status status() const override {
if (!status_.ok()) {
return status_;
}
if (!base_iterator_->status().ok()) {
return base_iterator_->status();
}
return delta_iterator_->status();
}
private:
void AssertInvariants() {
#ifndef NDEBUG
bool not_ok = false;
if (!base_iterator_->status().ok()) {
assert(!base_iterator_->Valid());
not_ok = true;
}
if (!delta_iterator_->status().ok()) {
assert(!delta_iterator_->Valid());
not_ok = true;
}
if (not_ok) {
assert(!Valid());
assert(!status().ok());
return;
}
if (!Valid()) {
return;
}
if (!BaseValid()) {
assert(!current_at_base_ && delta_iterator_->Valid());
return;
}
if (!DeltaValid()) {
assert(current_at_base_ && base_iterator_->Valid());
return;
}
// we don't support those yet
assert(delta_iterator_->Entry().type != kMergeRecord &&
delta_iterator_->Entry().type != kLogDataRecord);
int compare = comparator_->Compare(delta_iterator_->Entry().key,
base_iterator_->key());
if (forward_) {
// current_at_base -> compare < 0
assert(!current_at_base_ || compare < 0);
// !current_at_base -> compare <= 0
assert(current_at_base_ && compare >= 0);
} else {
// current_at_base -> compare > 0
assert(!current_at_base_ || compare > 0);
// !current_at_base -> compare <= 0
assert(current_at_base_ && compare <= 0);
}
// equal_keys_ <=> compare == 0
assert((equal_keys_ || compare != 0) && (!equal_keys_ || compare == 0));
#endif
}
void Advance() {
if (equal_keys_) {
assert(BaseValid() && DeltaValid());
AdvanceBase();
AdvanceDelta();
} else {
if (current_at_base_) {
assert(BaseValid());
AdvanceBase();
} else {
assert(DeltaValid());
AdvanceDelta();
}
}
UpdateCurrent();
}
void AdvanceDelta() {
if (forward_) {
delta_iterator_->Next();
} else {
delta_iterator_->Prev();
}
}
void AdvanceBase() {
if (forward_) {
base_iterator_->Next();
} else {
base_iterator_->Prev();
}
}
bool BaseValid() const { return base_iterator_->Valid(); }
bool DeltaValid() const { return delta_iterator_->Valid(); }
void UpdateCurrent() {
// Suppress false positive clang analyzer warnings.
#ifndef __clang_analyzer__
status_ = Status::OK();
while (true) {
WriteEntry delta_entry;
if (DeltaValid()) {
assert(delta_iterator_->status().ok());
delta_entry = delta_iterator_->Entry();
} else if (!delta_iterator_->status().ok()) {
// Expose the error status and stop.
current_at_base_ = false;
return;
}
equal_keys_ = false;
if (!BaseValid()) {
if (!base_iterator_->status().ok()) {
// Expose the error status and stop.
current_at_base_ = true;
return;
}
// Base has finished.
if (!DeltaValid()) {
// Finished
return;
}
if (delta_entry.type == kDeleteRecord ||
delta_entry.type == kSingleDeleteRecord) {
AdvanceDelta();
} else {
current_at_base_ = false;
return;
}
} else if (!DeltaValid()) {
// Delta has finished.
current_at_base_ = true;
return;
} else {
int compare =
(forward_ ? 1 : -1) *
comparator_->Compare(delta_entry.key, base_iterator_->key());
if (compare <= 0) { // delta bigger or equal
if (compare == 0) {
equal_keys_ = true;
}
if (delta_entry.type != kDeleteRecord &&
delta_entry.type != kSingleDeleteRecord) {
current_at_base_ = false;
return;
}
// Delta is less advanced and is delete.
AdvanceDelta();
if (equal_keys_) {
AdvanceBase();
}
} else {
current_at_base_ = true;
return;
}
}
}
AssertInvariants();
#endif // __clang_analyzer__
}
bool forward_;
bool current_at_base_;
bool equal_keys_;
Status status_;
std::unique_ptr<Iterator> base_iterator_;
std::unique_ptr<WBWIIterator> delta_iterator_;
const Comparator* comparator_; // not owned
};
typedef SkipList<WriteBatchIndexEntry*, const WriteBatchEntryComparator&>
WriteBatchEntrySkipList;
class WBWIIteratorImpl : public WBWIIterator {
public:
WBWIIteratorImpl(uint32_t column_family_id,
WriteBatchEntrySkipList* skip_list,
const ReadableWriteBatch* write_batch)
: column_family_id_(column_family_id),
skip_list_iter_(skip_list),
write_batch_(write_batch) {}
virtual ~WBWIIteratorImpl() {}
virtual bool Valid() const override {
if (!skip_list_iter_.Valid()) {
return false;
}
const WriteBatchIndexEntry* iter_entry = skip_list_iter_.key();
return (iter_entry != nullptr &&
iter_entry->column_family == column_family_id_);
}
virtual void SeekToFirst() override {
WriteBatchIndexEntry search_entry(WriteBatchIndexEntry::kFlagMin,
column_family_id_, 0, 0);
skip_list_iter_.Seek(&search_entry);
}
virtual void SeekToLast() override {
WriteBatchIndexEntry search_entry(WriteBatchIndexEntry::kFlagMin,
column_family_id_ + 1, 0, 0);
skip_list_iter_.Seek(&search_entry);
if (!skip_list_iter_.Valid()) {
skip_list_iter_.SeekToLast();
} else {
skip_list_iter_.Prev();
}
}
virtual void Seek(const Slice& key) override {
WriteBatchIndexEntry search_entry(&key, column_family_id_);
skip_list_iter_.Seek(&search_entry);
}
virtual void SeekForPrev(const Slice& key) override {
WriteBatchIndexEntry search_entry(&key, column_family_id_);
skip_list_iter_.SeekForPrev(&search_entry);
}
virtual void Next() override { skip_list_iter_.Next(); }
virtual void Prev() override { skip_list_iter_.Prev(); }
virtual WriteEntry Entry() const override {
WriteEntry ret;
Slice blob, xid;
const WriteBatchIndexEntry* iter_entry = skip_list_iter_.key();
// this is guaranteed with Valid()
assert(iter_entry != nullptr &&
iter_entry->column_family == column_family_id_);
auto s = write_batch_->GetEntryFromDataOffset(
iter_entry->offset, &ret.type, &ret.key, &ret.value, &blob, &xid);
assert(s.ok());
assert(ret.type == kPutRecord || ret.type == kDeleteRecord ||
ret.type == kSingleDeleteRecord || ret.type == kDeleteRangeRecord ||
ret.type == kMergeRecord);
return ret;
}
virtual Status status() const override {
// this is in-memory data structure, so the only way status can be non-ok is
// through memory corruption
return Status::OK();
}
const WriteBatchIndexEntry* GetRawEntry() const {
return skip_list_iter_.key();
}
private:
uint32_t column_family_id_;
WriteBatchEntrySkipList::Iterator skip_list_iter_;
const ReadableWriteBatch* write_batch_;
};
struct WriteBatchWithIndex::Rep {
explicit Rep(const Comparator* index_comparator, size_t reserved_bytes = 0,
size_t max_bytes = 0, bool _overwrite_key = false)
: write_batch(reserved_bytes, max_bytes),
comparator(index_comparator, &write_batch),
skip_list(comparator, &arena),
overwrite_key(_overwrite_key),
last_entry_offset(0),
last_sub_batch_offset(0),
sub_batch_cnt(1) {}
ReadableWriteBatch write_batch;
WriteBatchEntryComparator comparator;
Arena arena;
WriteBatchEntrySkipList skip_list;
bool overwrite_key;
size_t last_entry_offset;
// The starting offset of the last sub-batch. A sub-batch starts right before
// inserting a key that is a duplicate of a key in the last sub-batch. Zero,
// the default, means that no duplicate key is detected so far.
size_t last_sub_batch_offset;
// Total number of sub-batches in the write batch. Default is 1.
size_t sub_batch_cnt;
// Remember current offset of internal write batch, which is used as
// the starting offset of the next record.
void SetLastEntryOffset() { last_entry_offset = write_batch.GetDataSize(); }
// In overwrite mode, find the existing entry for the same key and update it
// to point to the current entry.
// Return true if the key is found and updated.
bool UpdateExistingEntry(ColumnFamilyHandle* column_family, const Slice& key);
bool UpdateExistingEntryWithCfId(uint32_t column_family_id, const Slice& key);
// Add the recent entry to the update.
// In overwrite mode, if key already exists in the index, update it.
void AddOrUpdateIndex(ColumnFamilyHandle* column_family, const Slice& key);
void AddOrUpdateIndex(const Slice& key);
// Allocate an index entry pointing to the last entry in the write batch and
// put it to skip list.
void AddNewEntry(uint32_t column_family_id);
// Clear all updates buffered in this batch.
void Clear();
void ClearIndex();
// Rebuild index by reading all records from the batch.
// Returns non-ok status on corruption.
Status ReBuildIndex();
};
bool WriteBatchWithIndex::Rep::UpdateExistingEntry(
ColumnFamilyHandle* column_family, const Slice& key) {
uint32_t cf_id = GetColumnFamilyID(column_family);
return UpdateExistingEntryWithCfId(cf_id, key);
}
bool WriteBatchWithIndex::Rep::UpdateExistingEntryWithCfId(
uint32_t column_family_id, const Slice& key) {
if (!overwrite_key) {
return false;
}
WBWIIteratorImpl iter(column_family_id, &skip_list, &write_batch);
iter.Seek(key);
if (!iter.Valid()) {
return false;
}
if (comparator.CompareKey(column_family_id, key, iter.Entry().key) != 0) {
return false;
}
WriteBatchIndexEntry* non_const_entry =
const_cast<WriteBatchIndexEntry*>(iter.GetRawEntry());
if (LIKELY(last_sub_batch_offset <= non_const_entry->offset)) {
last_sub_batch_offset = last_entry_offset;
sub_batch_cnt++;
}
non_const_entry->offset = last_entry_offset;
return true;
}
void WriteBatchWithIndex::Rep::AddOrUpdateIndex(
ColumnFamilyHandle* column_family, const Slice& key) {
if (!UpdateExistingEntry(column_family, key)) {
uint32_t cf_id = GetColumnFamilyID(column_family);
const auto* cf_cmp = GetColumnFamilyUserComparator(column_family);
if (cf_cmp != nullptr) {
comparator.SetComparatorForCF(cf_id, cf_cmp);
}
AddNewEntry(cf_id);
}
}
void WriteBatchWithIndex::Rep::AddOrUpdateIndex(const Slice& key) {
if (!UpdateExistingEntryWithCfId(0, key)) {
AddNewEntry(0);
}
}
void WriteBatchWithIndex::Rep::AddNewEntry(uint32_t column_family_id) {
const std::string& wb_data = write_batch.Data();
Slice entry_ptr = Slice(wb_data.data() + last_entry_offset,
wb_data.size() - last_entry_offset);
// Extract key
Slice key;
bool success __attribute__((__unused__));
success =
ReadKeyFromWriteBatchEntry(&entry_ptr, &key, column_family_id != 0);
assert(success);
auto* mem = arena.Allocate(sizeof(WriteBatchIndexEntry));
auto* index_entry =
new (mem) WriteBatchIndexEntry(last_entry_offset, column_family_id,
key.data() - wb_data.data(), key.size());
skip_list.Insert(index_entry);
}
void WriteBatchWithIndex::Rep::Clear() {
write_batch.Clear();
ClearIndex();
}
void WriteBatchWithIndex::Rep::ClearIndex() {
skip_list.~WriteBatchEntrySkipList();
arena.~Arena();
new (&arena) Arena();
new (&skip_list) WriteBatchEntrySkipList(comparator, &arena);
last_entry_offset = 0;
last_sub_batch_offset = 0;
sub_batch_cnt = 1;
}
Status WriteBatchWithIndex::Rep::ReBuildIndex() {
Status s;
ClearIndex();
if (write_batch.Count() == 0) {
// Nothing to re-index
return s;
}
size_t offset = WriteBatchInternal::GetFirstOffset(&write_batch);
Slice input(write_batch.Data());
input.remove_prefix(offset);
// Loop through all entries in Rep and add each one to the index
int found = 0;
while (s.ok() && !input.empty()) {
Slice key, value, blob, xid;
uint32_t column_family_id = 0; // default
char tag = 0;
// set offset of current entry for call to AddNewEntry()
last_entry_offset = input.data() - write_batch.Data().data();
s = ReadRecordFromWriteBatch(&input, &tag, &column_family_id, &key,
&value, &blob, &xid);
if (!s.ok()) {
break;
}
switch (tag) {
case kTypeColumnFamilyValue:
case kTypeValue:
case kTypeColumnFamilyDeletion:
case kTypeDeletion:
case kTypeColumnFamilySingleDeletion:
case kTypeSingleDeletion:
case kTypeColumnFamilyMerge:
case kTypeMerge:
found++;
if (!UpdateExistingEntryWithCfId(column_family_id, key)) {
AddNewEntry(column_family_id);
}
break;
case kTypeLogData:
case kTypeBeginPrepareXID:
case kTypeBeginPersistedPrepareXID:
case kTypeEndPrepareXID:
case kTypeCommitXID:
case kTypeRollbackXID:
case kTypeNoop:
break;
default:
return Status::Corruption("unknown WriteBatch tag in ReBuildIndex",
ToString(static_cast<unsigned int>(tag)));
}
}
if (s.ok() && found != write_batch.Count()) {
s = Status::Corruption("WriteBatch has wrong count");
}
return s;
}
WriteBatchWithIndex::WriteBatchWithIndex(
const Comparator* default_index_comparator, size_t reserved_bytes,
bool overwrite_key, size_t max_bytes)
: rep(new Rep(default_index_comparator, reserved_bytes, max_bytes,
overwrite_key)) {}
WriteBatchWithIndex::~WriteBatchWithIndex() {}
WriteBatch* WriteBatchWithIndex::GetWriteBatch() { return &rep->write_batch; }
size_t WriteBatchWithIndex::SubBatchCnt() { return rep->sub_batch_cnt; }
WBWIIterator* WriteBatchWithIndex::NewIterator() {
return new WBWIIteratorImpl(0, &(rep->skip_list), &rep->write_batch);
}
WBWIIterator* WriteBatchWithIndex::NewIterator(
ColumnFamilyHandle* column_family) {
return new WBWIIteratorImpl(GetColumnFamilyID(column_family),
&(rep->skip_list), &rep->write_batch);
}
Iterator* WriteBatchWithIndex::NewIteratorWithBase(
ColumnFamilyHandle* column_family, Iterator* base_iterator) {
if (rep->overwrite_key == false) {
assert(false);
return nullptr;
}
return new BaseDeltaIterator(base_iterator, NewIterator(column_family),
GetColumnFamilyUserComparator(column_family));
}
Iterator* WriteBatchWithIndex::NewIteratorWithBase(Iterator* base_iterator) {
if (rep->overwrite_key == false) {
assert(false);
return nullptr;
}
// default column family's comparator
return new BaseDeltaIterator(base_iterator, NewIterator(),
rep->comparator.default_comparator());
}
Status WriteBatchWithIndex::Put(ColumnFamilyHandle* column_family,
const Slice& key, const Slice& value) {
rep->SetLastEntryOffset();
auto s = rep->write_batch.Put(column_family, key, value);
if (s.ok()) {
rep->AddOrUpdateIndex(column_family, key);
}
return s;
}
Status WriteBatchWithIndex::Put(const Slice& key, const Slice& value) {
rep->SetLastEntryOffset();
auto s = rep->write_batch.Put(key, value);
if (s.ok()) {
rep->AddOrUpdateIndex(key);
}
return s;
}
Status WriteBatchWithIndex::Delete(ColumnFamilyHandle* column_family,
const Slice& key) {
rep->SetLastEntryOffset();
auto s = rep->write_batch.Delete(column_family, key);
if (s.ok()) {
rep->AddOrUpdateIndex(column_family, key);
}
return s;
}
Status WriteBatchWithIndex::Delete(const Slice& key) {
rep->SetLastEntryOffset();
auto s = rep->write_batch.Delete(key);
if (s.ok()) {
rep->AddOrUpdateIndex(key);
}
return s;
}
Status WriteBatchWithIndex::SingleDelete(ColumnFamilyHandle* column_family,
const Slice& key) {
rep->SetLastEntryOffset();
auto s = rep->write_batch.SingleDelete(column_family, key);
if (s.ok()) {
rep->AddOrUpdateIndex(column_family, key);
}
return s;
}
Status WriteBatchWithIndex::SingleDelete(const Slice& key) {
rep->SetLastEntryOffset();
auto s = rep->write_batch.SingleDelete(key);
if (s.ok()) {
rep->AddOrUpdateIndex(key);
}
return s;
}
Status WriteBatchWithIndex::DeleteRange(ColumnFamilyHandle* column_family,
const Slice& begin_key,
const Slice& end_key) {
rep->SetLastEntryOffset();
auto s = rep->write_batch.DeleteRange(column_family, begin_key, end_key);
if (s.ok()) {
rep->AddOrUpdateIndex(column_family, begin_key);
}
return s;
}
Status WriteBatchWithIndex::DeleteRange(const Slice& begin_key,
const Slice& end_key) {
rep->SetLastEntryOffset();
auto s = rep->write_batch.DeleteRange(begin_key, end_key);
if (s.ok()) {
rep->AddOrUpdateIndex(begin_key);
}
return s;
}
Status WriteBatchWithIndex::Merge(ColumnFamilyHandle* column_family,
const Slice& key, const Slice& value) {
rep->SetLastEntryOffset();
auto s = rep->write_batch.Merge(column_family, key, value);
if (s.ok()) {
rep->AddOrUpdateIndex(column_family, key);
}
return s;
}
Status WriteBatchWithIndex::Merge(const Slice& key, const Slice& value) {
rep->SetLastEntryOffset();
auto s = rep->write_batch.Merge(key, value);
if (s.ok()) {
rep->AddOrUpdateIndex(key);
}
return s;
}
Status WriteBatchWithIndex::PutLogData(const Slice& blob) {
return rep->write_batch.PutLogData(blob);
}
void WriteBatchWithIndex::Clear() { rep->Clear(); }
Status WriteBatchWithIndex::GetFromBatch(ColumnFamilyHandle* column_family,
const DBOptions& options,
const Slice& key, std::string* value) {
Status s;
MergeContext merge_context;
const ImmutableDBOptions immuable_db_options(options);
WriteBatchWithIndexInternal::Result result =
WriteBatchWithIndexInternal::GetFromBatch(
immuable_db_options, this, column_family, key, &merge_context,
&rep->comparator, value, rep->overwrite_key, &s);
switch (result) {
case WriteBatchWithIndexInternal::Result::kFound:
case WriteBatchWithIndexInternal::Result::kError:
// use returned status
break;
case WriteBatchWithIndexInternal::Result::kDeleted:
case WriteBatchWithIndexInternal::Result::kNotFound:
s = Status::NotFound();
break;
case WriteBatchWithIndexInternal::Result::kMergeInProgress:
s = Status::MergeInProgress();
break;
default:
assert(false);
}
return s;
}
Status WriteBatchWithIndex::GetFromBatchAndDB(DB* db,
const ReadOptions& read_options,
const Slice& key,
std::string* value) {
assert(value != nullptr);
PinnableSlice pinnable_val(value);
assert(!pinnable_val.IsPinned());
auto s = GetFromBatchAndDB(db, read_options, db->DefaultColumnFamily(), key,
&pinnable_val);
if (s.ok() && pinnable_val.IsPinned()) {
value->assign(pinnable_val.data(), pinnable_val.size());
} // else value is already assigned
return s;
}
Status WriteBatchWithIndex::GetFromBatchAndDB(DB* db,
const ReadOptions& read_options,
const Slice& key,
PinnableSlice* pinnable_val) {
return GetFromBatchAndDB(db, read_options, db->DefaultColumnFamily(), key,
pinnable_val);
}
Status WriteBatchWithIndex::GetFromBatchAndDB(DB* db,
const ReadOptions& read_options,
ColumnFamilyHandle* column_family,
const Slice& key,
std::string* value) {
assert(value != nullptr);
PinnableSlice pinnable_val(value);
assert(!pinnable_val.IsPinned());
auto s =
GetFromBatchAndDB(db, read_options, column_family, key, &pinnable_val);
if (s.ok() && pinnable_val.IsPinned()) {
value->assign(pinnable_val.data(), pinnable_val.size());
} // else value is already assigned
return s;
}
Status WriteBatchWithIndex::GetFromBatchAndDB(DB* db,
const ReadOptions& read_options,
ColumnFamilyHandle* column_family,
const Slice& key,
PinnableSlice* pinnable_val) {
return GetFromBatchAndDB(db, read_options, column_family, key, pinnable_val,
nullptr);
}
Status WriteBatchWithIndex::GetFromBatchAndDB(
DB* db, const ReadOptions& read_options, ColumnFamilyHandle* column_family,
const Slice& key, PinnableSlice* pinnable_val, ReadCallback* callback) {
Status s;
MergeContext merge_context;
const ImmutableDBOptions& immuable_db_options =
static_cast_with_check<DBImpl, DB>(db->GetRootDB())
->immutable_db_options();
// Since the lifetime of the WriteBatch is the same as that of the transaction
// we cannot pin it as otherwise the returned value will not be available
// after the transaction finishes.
std::string& batch_value = *pinnable_val->GetSelf();
WriteBatchWithIndexInternal::Result result =
WriteBatchWithIndexInternal::GetFromBatch(
immuable_db_options, this, column_family, key, &merge_context,
&rep->comparator, &batch_value, rep->overwrite_key, &s);
if (result == WriteBatchWithIndexInternal::Result::kFound) {
pinnable_val->PinSelf();
return s;
}
if (result == WriteBatchWithIndexInternal::Result::kDeleted) {
return Status::NotFound();
}
if (result == WriteBatchWithIndexInternal::Result::kError) {
return s;
}
if (result == WriteBatchWithIndexInternal::Result::kMergeInProgress &&
rep->overwrite_key == true) {
// Since we've overwritten keys, we do not know what other operations are
// in this batch for this key, so we cannot do a Merge to compute the
// result. Instead, we will simply return MergeInProgress.
return Status::MergeInProgress();
}
assert(result == WriteBatchWithIndexInternal::Result::kMergeInProgress ||
result == WriteBatchWithIndexInternal::Result::kNotFound);
// Did not find key in batch OR could not resolve Merges. Try DB.
if (!callback) {
s = db->Get(read_options, column_family, key, pinnable_val);
} else {
s = static_cast_with_check<DBImpl, DB>(db->GetRootDB())
->GetImpl(read_options, column_family, key, pinnable_val, nullptr,
callback);
}
if (s.ok() || s.IsNotFound()) { // DB Get Succeeded
if (result == WriteBatchWithIndexInternal::Result::kMergeInProgress) {
// Merge result from DB with merges in Batch
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
const MergeOperator* merge_operator =
cfh->cfd()->ioptions()->merge_operator;
Statistics* statistics = immuable_db_options.statistics.get();
Env* env = immuable_db_options.env;
Logger* logger = immuable_db_options.info_log.get();
Slice* merge_data;
if (s.ok()) {
merge_data = pinnable_val;
} else { // Key not present in db (s.IsNotFound())
merge_data = nullptr;
}
if (merge_operator) {
s = MergeHelper::TimedFullMerge(
merge_operator, key, merge_data, merge_context.GetOperands(),
pinnable_val->GetSelf(), logger, statistics, env);
pinnable_val->PinSelf();
} else {
s = Status::InvalidArgument("Options::merge_operator must be set");
}
}
}
return s;
}
void WriteBatchWithIndex::SetSavePoint() { rep->write_batch.SetSavePoint(); }
Status WriteBatchWithIndex::RollbackToSavePoint() {
Status s = rep->write_batch.RollbackToSavePoint();
if (s.ok()) {
rep->sub_batch_cnt = 1;
rep->last_sub_batch_offset = 0;
s = rep->ReBuildIndex();
}
return s;
}
Status WriteBatchWithIndex::PopSavePoint() {
return rep->write_batch.PopSavePoint();
}
void WriteBatchWithIndex::SetMaxBytes(size_t max_bytes) {
rep->write_batch.SetMaxBytes(max_bytes);
}
} // namespace rocksdb
#endif // !ROCKSDB_LITE