1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
|
// Copyright (c) 2011-present, 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.
#pragma once
#ifndef ROCKSDB_LITE
#include <string>
#include <unordered_map>
#include "rocksdb/db.h"
#include "rocksdb/slice.h"
#include "rocksdb/status.h"
#include "rocksdb/types.h"
namespace rocksdb {
struct TransactionKeyMapInfo {
// Earliest sequence number that is relevant to this transaction for this key
SequenceNumber seq;
uint32_t num_writes;
uint32_t num_reads;
explicit TransactionKeyMapInfo(SequenceNumber seq_no)
: seq(seq_no), num_writes(0), num_reads(0) {}
};
using TransactionKeyMap =
std::unordered_map<uint32_t,
std::unordered_map<std::string, TransactionKeyMapInfo>>;
class DBImpl;
struct SuperVersion;
class WriteBatchWithIndex;
class TransactionUtil {
public:
// Verifies there have been no writes to this key in the db since this
// sequence number.
//
// If cache_only is true, then this function will not attempt to read any
// SST files. This will make it more likely this function will
// return an error if it is unable to determine if there are any conflicts.
//
// Returns OK on success, BUSY if there is a conflicting write, or other error
// status for any unexpected errors.
static Status CheckKeyForConflicts(DBImpl* db_impl,
ColumnFamilyHandle* column_family,
const std::string& key,
SequenceNumber key_seq, bool cache_only);
// For each key,SequenceNumber pair in the TransactionKeyMap, this function
// will verify there have been no writes to the key in the db since that
// sequence number.
//
// Returns OK on success, BUSY if there is a conflicting write, or other error
// status for any unexpected errors.
//
// REQUIRED: this function should only be called on the write thread or if the
// mutex is held.
static Status CheckKeysForConflicts(DBImpl* db_impl,
const TransactionKeyMap& keys,
bool cache_only);
private:
static Status CheckKey(DBImpl* db_impl, SuperVersion* sv,
SequenceNumber earliest_seq, SequenceNumber key_seq,
const std::string& key, bool cache_only);
};
} // namespace rocksdb
#endif // ROCKSDB_LITE
|
