mirror of
https://github.com/facebook/rocksdb.git
synced 2024-11-27 02:44:18 +00:00
2faf49d5f1
Summary: Intead of passing callback function pointer and its arg on Table::Get() interface, passing GetContext. This makes the interface cleaner and possible better perf. Also adding a fast pass for SaveValue() Test Plan: make all check Reviewers: igor, yhchiang, sdong Reviewed By: sdong Subscribers: leveldb Differential Revision: https://reviews.facebook.net/D24057
102 lines
3.3 KiB
C++
102 lines
3.3 KiB
C++
// Copyright (c) 2014, Facebook, Inc. All rights reserved.
|
|
// This source code is licensed under the BSD-style license found in the
|
|
// LICENSE file in the root directory of this source tree. An additional grant
|
|
// of patent rights can be found in the PATENTS file in the same directory.
|
|
|
|
#include "table/get_context.h"
|
|
#include "rocksdb/merge_operator.h"
|
|
#include "rocksdb/statistics.h"
|
|
#include "util/statistics.h"
|
|
|
|
namespace rocksdb {
|
|
|
|
GetContext::GetContext(const Comparator* ucmp,
|
|
const MergeOperator* merge_operator,
|
|
Logger* logger, Statistics* statistics,
|
|
GetState init_state, const Slice& user_key, std::string* ret_value,
|
|
bool* value_found, MergeContext* merge_context)
|
|
: ucmp_(ucmp),
|
|
merge_operator_(merge_operator),
|
|
logger_(logger),
|
|
statistics_(statistics),
|
|
state_(init_state),
|
|
user_key_(user_key),
|
|
value_(ret_value),
|
|
value_found_(value_found),
|
|
merge_context_(merge_context) {
|
|
}
|
|
|
|
// Called from TableCache::Get and Table::Get when file/block in which
|
|
// key may exist are not there in TableCache/BlockCache respectively. In this
|
|
// case we can't guarantee that key does not exist and are not permitted to do
|
|
// IO to be certain.Set the status=kFound and value_found=false to let the
|
|
// caller know that key may exist but is not there in memory
|
|
void GetContext::MarkKeyMayExist() {
|
|
state_ = kFound;
|
|
if (value_found_ != nullptr) {
|
|
*value_found_ = false;
|
|
}
|
|
}
|
|
|
|
void GetContext::SaveValue(const Slice& value) {
|
|
state_ = kFound;
|
|
value_->assign(value.data(), value.size());
|
|
}
|
|
|
|
bool GetContext::SaveValue(const ParsedInternalKey& parsed_key,
|
|
const Slice& value) {
|
|
assert((state_ != kMerge && parsed_key.type != kTypeMerge) ||
|
|
merge_context_ != nullptr);
|
|
if (ucmp_->Compare(parsed_key.user_key, user_key_) == 0) {
|
|
// Key matches. Process it
|
|
switch (parsed_key.type) {
|
|
case kTypeValue:
|
|
assert(state_ == kNotFound || state_ == kMerge);
|
|
if (kNotFound == state_) {
|
|
state_ = kFound;
|
|
value_->assign(value.data(), value.size());
|
|
} else if (kMerge == state_) {
|
|
assert(merge_operator_ != nullptr);
|
|
state_ = kFound;
|
|
if (!merge_operator_->FullMerge(user_key_, &value,
|
|
merge_context_->GetOperands(),
|
|
value_, logger_)) {
|
|
RecordTick(statistics_, NUMBER_MERGE_FAILURES);
|
|
state_ = kCorrupt;
|
|
}
|
|
}
|
|
return false;
|
|
|
|
case kTypeDeletion:
|
|
assert(state_ == kNotFound || state_ == kMerge);
|
|
if (kNotFound == state_) {
|
|
state_ = kDeleted;
|
|
} else if (kMerge == state_) {
|
|
state_ = kFound;
|
|
if (!merge_operator_->FullMerge(user_key_, nullptr,
|
|
merge_context_->GetOperands(),
|
|
value_, logger_)) {
|
|
RecordTick(statistics_, NUMBER_MERGE_FAILURES);
|
|
state_ = kCorrupt;
|
|
}
|
|
}
|
|
return false;
|
|
|
|
case kTypeMerge:
|
|
assert(state_ == kNotFound || state_ == kMerge);
|
|
state_ = kMerge;
|
|
merge_context_->PushOperand(value);
|
|
return true;
|
|
|
|
default:
|
|
assert(false);
|
|
break;
|
|
}
|
|
}
|
|
|
|
// state_ could be Corrupt, merge or notfound
|
|
return false;
|
|
}
|
|
|
|
} // namespace rocksdb
|