1 | /* |
2 | * Copyright 2018-present Facebook, Inc. |
3 | * |
4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
5 | * you may not use this file except in compliance with the License. |
6 | * You may obtain a copy of the License at |
7 | * |
8 | * http://www.apache.org/licenses/LICENSE-2.0 |
9 | * |
10 | * Unless required by applicable law or agreed to in writing, software |
11 | * distributed under the License is distributed on an "AS IS" BASIS, |
12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
13 | * See the License for the specific language governing permissions and |
14 | * limitations under the License. |
15 | */ |
16 | |
17 | #pragma once |
18 | |
19 | #include <string> |
20 | |
21 | #include <folly/Function.h> |
22 | #include <folly/Optional.h> |
23 | #include <folly/Range.h> |
24 | |
25 | namespace folly { |
26 | namespace io { |
27 | enum class CodecType; |
28 | } // namespace io |
29 | |
30 | enum class CompressionCounterKey { |
31 | BYTES_BEFORE_COMPRESSION = 0, |
32 | BYTES_AFTER_COMPRESSION = 1, |
33 | BYTES_BEFORE_DECOMPRESSION = 2, |
34 | BYTES_AFTER_DECOMPRESSION = 3, |
35 | COMPRESSIONS = 4, |
36 | DECOMPRESSIONS = 5, |
37 | COMPRESSION_MILLISECONDS = 6, |
38 | DECOMPRESSION_MILLISECONDS = 7, |
39 | }; |
40 | |
41 | enum class CompressionCounterType { |
42 | AVG = 0, |
43 | SUM = 1, |
44 | }; |
45 | |
46 | /** |
47 | * This functions is an extension point when FOLLY_HAVE_WEAK_SYMBOLS is true. |
48 | * There is a default no-op implementation provided which can be overrided by |
49 | * linking in a library which provides its own definition. |
50 | * |
51 | * @param codecType The type of the codec for this counter. |
52 | * @param codecName The name of the codec for this counter. If the codecName |
53 | * is empty it should be defaulted using the codecType. |
54 | * @param level Optionally the level used to construct the codec. |
55 | * @param key The key of the counter. |
56 | * @param counterType The type of the counter. |
57 | * @returns A function to increment the counter for the given key and |
58 | * type. It may be an empty folly::Function. |
59 | */ |
60 | folly::Function<void(double)> makeCompressionCounterHandler( |
61 | folly::io::CodecType codecType, |
62 | folly::StringPiece codecName, |
63 | folly::Optional<int> level, |
64 | CompressionCounterKey key, |
65 | CompressionCounterType counterType); |
66 | |
67 | namespace detail { |
68 | |
69 | /// Wrapper around the makeCompressionCounterHandler() extension point. |
70 | class CompressionCounter { |
71 | public: |
72 | CompressionCounter() {} |
73 | CompressionCounter( |
74 | folly::io::CodecType codecType, |
75 | folly::StringPiece codecName, |
76 | folly::Optional<int> level, |
77 | CompressionCounterKey key, |
78 | CompressionCounterType counterType) { |
79 | initialize_ = [=]() { |
80 | return makeCompressionCounterHandler( |
81 | codecType, codecName, level, key, counterType); |
82 | }; |
83 | DCHECK(!initialize_.hasAllocatedMemory()); |
84 | } |
85 | |
86 | void operator+=(double sum) { |
87 | performLazyInit(); |
88 | if (increment_) { |
89 | increment_(sum); |
90 | } |
91 | } |
92 | |
93 | void operator++() { |
94 | *this += 1.0; |
95 | } |
96 | |
97 | void operator++(int) { |
98 | *this += 1.0; |
99 | } |
100 | |
101 | bool hasImplementation() { |
102 | performLazyInit(); |
103 | return static_cast<bool>(increment_); |
104 | } |
105 | |
106 | private: |
107 | void performLazyInit() { |
108 | if (!initialized_) { |
109 | initialized_ = true; |
110 | increment_ = initialize_(); |
111 | initialize_ = {}; |
112 | } |
113 | } |
114 | |
115 | bool initialized_{false}; |
116 | folly::Function<folly::Function<void(double)>()> initialize_; |
117 | folly::Function<void(double)> increment_; |
118 | }; |
119 | |
120 | } // namespace detail |
121 | } // namespace folly |
122 | |