92c1eb0291
Summary: This will allow us to disable them completely for iOS or for better performance Test Plan: will run make all check Reviewers: igor, haobo, dhruba Reviewed By: haobo CC: leveldb Differential Revision: https://reviews.facebook.net/D17511
170 lines
5.5 KiB
C++
170 lines
5.5 KiB
C++
// Copyright (c) 2013, 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.
|
|
//
|
|
// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style license that can be
|
|
// found in the LICENSE file. See the AUTHORS file for names of contributors.
|
|
#include "db/dbformat.h"
|
|
|
|
#include <stdio.h>
|
|
#include "port/port.h"
|
|
#include "util/coding.h"
|
|
#include "util/perf_context_imp.h"
|
|
|
|
namespace rocksdb {
|
|
|
|
uint64_t PackSequenceAndType(uint64_t seq, ValueType t) {
|
|
assert(seq <= kMaxSequenceNumber);
|
|
assert(t <= kValueTypeForSeek);
|
|
return (seq << 8) | t;
|
|
}
|
|
|
|
void AppendInternalKey(std::string* result, const ParsedInternalKey& key) {
|
|
result->append(key.user_key.data(), key.user_key.size());
|
|
PutFixed64(result, PackSequenceAndType(key.sequence, key.type));
|
|
}
|
|
|
|
std::string ParsedInternalKey::DebugString(bool hex) const {
|
|
char buf[50];
|
|
snprintf(buf, sizeof(buf), "' @ %llu : %d",
|
|
(unsigned long long) sequence,
|
|
int(type));
|
|
std::string result = "'";
|
|
result += user_key.ToString(hex);
|
|
result += buf;
|
|
return result;
|
|
}
|
|
|
|
std::string InternalKey::DebugString(bool hex) const {
|
|
std::string result;
|
|
ParsedInternalKey parsed;
|
|
if (ParseInternalKey(rep_, &parsed)) {
|
|
result = parsed.DebugString(hex);
|
|
} else {
|
|
result = "(bad)";
|
|
result.append(EscapeString(rep_));
|
|
}
|
|
return result;
|
|
}
|
|
|
|
const char* InternalKeyComparator::Name() const {
|
|
return name_.c_str();
|
|
}
|
|
|
|
int InternalKeyComparator::Compare(const Slice& akey, const Slice& bkey) const {
|
|
// Order by:
|
|
// increasing user key (according to user-supplied comparator)
|
|
// decreasing sequence number
|
|
// decreasing type (though sequence# should be enough to disambiguate)
|
|
int r = user_comparator_->Compare(ExtractUserKey(akey), ExtractUserKey(bkey));
|
|
PERF_COUNTER_ADD(user_key_comparison_count, 1);
|
|
if (r == 0) {
|
|
const uint64_t anum = DecodeFixed64(akey.data() + akey.size() - 8);
|
|
const uint64_t bnum = DecodeFixed64(bkey.data() + bkey.size() - 8);
|
|
if (anum > bnum) {
|
|
r = -1;
|
|
} else if (anum < bnum) {
|
|
r = +1;
|
|
}
|
|
}
|
|
return r;
|
|
}
|
|
|
|
int InternalKeyComparator::Compare(const ParsedInternalKey& a,
|
|
const ParsedInternalKey& b) const {
|
|
// Order by:
|
|
// increasing user key (according to user-supplied comparator)
|
|
// decreasing sequence number
|
|
// decreasing type (though sequence# should be enough to disambiguate)
|
|
int r = user_comparator_->Compare(a.user_key, b.user_key);
|
|
PERF_COUNTER_ADD(user_key_comparison_count, 1);
|
|
if (r == 0) {
|
|
if (a.sequence > b.sequence) {
|
|
r = -1;
|
|
} else if (a.sequence < b.sequence) {
|
|
r = +1;
|
|
} else if (a.type > b.type) {
|
|
r = -1;
|
|
} else if (a.type < b.type) {
|
|
r = +1;
|
|
}
|
|
}
|
|
return r;
|
|
}
|
|
|
|
void InternalKeyComparator::FindShortestSeparator(
|
|
std::string* start,
|
|
const Slice& limit) const {
|
|
// Attempt to shorten the user portion of the key
|
|
Slice user_start = ExtractUserKey(*start);
|
|
Slice user_limit = ExtractUserKey(limit);
|
|
std::string tmp(user_start.data(), user_start.size());
|
|
user_comparator_->FindShortestSeparator(&tmp, user_limit);
|
|
if (tmp.size() < user_start.size() &&
|
|
user_comparator_->Compare(user_start, tmp) < 0) {
|
|
// User key has become shorter physically, but larger logically.
|
|
// Tack on the earliest possible number to the shortened user key.
|
|
PutFixed64(&tmp, PackSequenceAndType(kMaxSequenceNumber,kValueTypeForSeek));
|
|
assert(this->Compare(*start, tmp) < 0);
|
|
assert(this->Compare(tmp, limit) < 0);
|
|
start->swap(tmp);
|
|
}
|
|
}
|
|
|
|
void InternalKeyComparator::FindShortSuccessor(std::string* key) const {
|
|
Slice user_key = ExtractUserKey(*key);
|
|
std::string tmp(user_key.data(), user_key.size());
|
|
user_comparator_->FindShortSuccessor(&tmp);
|
|
if (tmp.size() < user_key.size() &&
|
|
user_comparator_->Compare(user_key, tmp) < 0) {
|
|
// User key has become shorter physically, but larger logically.
|
|
// Tack on the earliest possible number to the shortened user key.
|
|
PutFixed64(&tmp, PackSequenceAndType(kMaxSequenceNumber,kValueTypeForSeek));
|
|
assert(this->Compare(*key, tmp) < 0);
|
|
key->swap(tmp);
|
|
}
|
|
}
|
|
|
|
const char* InternalFilterPolicy::Name() const {
|
|
return user_policy_->Name();
|
|
}
|
|
|
|
void InternalFilterPolicy::CreateFilter(const Slice* keys, int n,
|
|
std::string* dst) const {
|
|
// We rely on the fact that the code in table.cc does not mind us
|
|
// adjusting keys[].
|
|
Slice* mkey = const_cast<Slice*>(keys);
|
|
for (int i = 0; i < n; i++) {
|
|
mkey[i] = ExtractUserKey(keys[i]);
|
|
// TODO(sanjay): Suppress dups?
|
|
}
|
|
user_policy_->CreateFilter(keys, n, dst);
|
|
}
|
|
|
|
bool InternalFilterPolicy::KeyMayMatch(const Slice& key, const Slice& f) const {
|
|
return user_policy_->KeyMayMatch(ExtractUserKey(key), f);
|
|
}
|
|
|
|
LookupKey::LookupKey(const Slice& user_key, SequenceNumber s) {
|
|
size_t usize = user_key.size();
|
|
size_t needed = usize + 13; // A conservative estimate
|
|
char* dst;
|
|
if (needed <= sizeof(space_)) {
|
|
dst = space_;
|
|
} else {
|
|
dst = new char[needed];
|
|
}
|
|
start_ = dst;
|
|
dst = EncodeVarint32(dst, usize + 8);
|
|
kstart_ = dst;
|
|
memcpy(dst, user_key.data(), usize);
|
|
dst += usize;
|
|
EncodeFixed64(dst, PackSequenceAndType(s, kValueTypeForSeek));
|
|
dst += 8;
|
|
end_ = dst;
|
|
}
|
|
|
|
} // namespace rocksdb
|