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
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
|
/**
* Copyright (C) 2018-present MongoDB, Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the Server Side Public License, version 1,
* as published by MongoDB, Inc.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* Server Side Public License for more details.
*
* You should have received a copy of the Server Side Public License
* along with this program. If not, see
* <http://www.mongodb.com/licensing/server-side-public-license>.
*
* As a special exception, the copyright holders give permission to link the
* code of portions of this program with the OpenSSL library under certain
* conditions as described in each individual source file and distribute
* linked combinations including the program with the OpenSSL library. You
* must comply with the Server Side Public License in all respects for
* all of the code used other than as permitted herein. If you modify file(s)
* with this exception, you may extend this exception to your version of the
* file(s), but you are not obligated to do so. If you do not wish to do so,
* delete this exception statement from your version. If you delete this
* exception statement from all source files in the program, then also delete
* it in the license file.
*/
#pragma once
#include <map>
#include <set>
#include "mongo/bson/bsonobj_comparator_interface.h"
#include "mongo/stdx/unordered_map.h"
#include "mongo/stdx/unordered_set.h"
namespace mongo {
/**
* A BSONObj comparator that has simple binary compare semantics.
*/
class SimpleBSONObjComparator final : public BSONObj::ComparatorInterface {
public:
// Global simple comparator for stateless BSONObj comparisons. BSONObj comparisons that require
// database logic, such as collations, must instantiate their own comparator.
static const SimpleBSONObjComparator kInstance;
int compare(const BSONObj& lhs, const BSONObj& rhs) const final {
return lhs.woCompare(rhs, BSONObj(), ComparisonRules::kConsiderFieldName, nullptr);
}
void hash_combine(size_t& seed, const BSONObj& toHash) const final {
hashCombineBSONObj(seed, toHash, ComparisonRules::kConsiderFieldName, nullptr);
}
/**
* A functor with simple binary comparison semantics that's suitable for use with ordered STL
* containers.
*/
class LessThan {
public:
explicit LessThan() = default;
bool operator()(const BSONObj& lhs, const BSONObj& rhs) const {
return kInstance.compare(lhs, rhs) < 0;
}
};
/**
* A functor with simple binary comparison semantics that's suitable for use with unordered STL
* containers.
*/
class EqualTo {
public:
explicit EqualTo() = default;
bool operator()(const BSONObj& lhs, const BSONObj& rhs) const {
return kInstance.compare(lhs, rhs) == 0;
}
};
/**
* Functor for computing the hash of a BSONObj, compatible for use with unordered STL
* containers.
*/
class Hasher {
public:
explicit Hasher() = default;
size_t operator()(const BSONObj& obj) const {
return kInstance.hash(obj);
}
};
};
/**
* A set of BSONObjs that performs comparisons with simple binary semantics.
*/
using SimpleBSONObjSet = std::set<BSONObj, SimpleBSONObjComparator::LessThan>;
/**
* A multiset of BSONObjs that performs comparisons with simple binary semantics.
*/
using SimpleBSONObjMultiSet = std::multiset<BSONObj, SimpleBSONObjComparator::LessThan>;
/**
* An unordered_set of BSONObjs that performs equality checks using simple binary semantics.
*/
using SimpleBSONObjUnorderedSet =
stdx::unordered_set<BSONObj, SimpleBSONObjComparator::Hasher, SimpleBSONObjComparator::EqualTo>;
/**
* A map keyed on BSONObj that performs comparisons with simple binary semantics.
*/
template <typename T>
using SimpleBSONObjMap = std::map<BSONObj, T, SimpleBSONObjComparator::LessThan>;
/**
* A multimap keyed on BSONObj that performs comparisons with simple binary semantics.
*/
template <typename T>
using SimpleBSONObjMultiMap = std::multimap<BSONObj, T, SimpleBSONObjComparator::LessThan>;
/**
* An unordered_map keyed on BSONObj that performs equality checks using simple binary semantics.
*/
template <typename T>
using SimpleBSONObjUnorderedMap = stdx::
unordered_map<BSONObj, T, SimpleBSONObjComparator::Hasher, SimpleBSONObjComparator::EqualTo>;
} // namespace mongo
|
