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
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
|
/*
* Copyright (c) 2017-2019 Cisco and/or its affiliates.
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#pragma once
#include <hicn/transport/core/manifest_format.h>
namespace utils {
using transport::core::NextSegmentCalculationStrategy;
class SuffixStrategy {
public:
static constexpr uint32_t INVALID_SUFFIX =
std::numeric_limits<uint32_t>::max();
SuffixStrategy(NextSegmentCalculationStrategy strategy)
: suffix_stragegy_(strategy),
total_count_(0),
final_suffix_(INVALID_SUFFIX) {}
virtual ~SuffixStrategy() = default;
virtual uint32_t getNextSuffix() = 0;
virtual uint32_t getFinalSuffix() { return final_suffix_; }
virtual void setFinalSuffix(std::uint32_t final_suffix) {
if (final_suffix != INVALID_SUFFIX) {
final_suffix_ = final_suffix;
}
}
virtual uint32_t getNextManifestSuffix() = 0;
virtual uint32_t getNextContentSuffix() = 0;
virtual void reset(uint32_t offset = 0) = 0;
virtual uint32_t getManifestCapacity() = 0;
virtual void setManifestCapacity(uint32_t capacity) = 0;
virtual uint32_t getTotalCount() { return total_count_; };
NextSegmentCalculationStrategy getSuffixStrategy() {
return suffix_stragegy_;
}
protected:
inline void incrementTotalCount() { total_count_++; };
protected:
NextSegmentCalculationStrategy suffix_stragegy_;
std::uint32_t total_count_;
std::uint32_t final_suffix_;
};
class IncrementalSuffixStrategy : public SuffixStrategy {
public:
IncrementalSuffixStrategy(std::uint32_t start_offset)
: SuffixStrategy(NextSegmentCalculationStrategy::INCREMENTAL),
next_suffix_(start_offset) {}
TRANSPORT_ALWAYS_INLINE std::uint32_t getNextSuffix() override {
incrementTotalCount();
return next_suffix_++;
}
TRANSPORT_ALWAYS_INLINE std::uint32_t getNextContentSuffix() override {
return getNextSuffix();
}
TRANSPORT_ALWAYS_INLINE std::uint32_t getNextManifestSuffix() override {
return getNextSuffix();
}
uint32_t getManifestCapacity() override {
throw errors::RuntimeException(
"No manifest capacity in IncrementalSuffixStrategy.");
}
void setManifestCapacity(uint32_t capacity) override {
throw errors::RuntimeException(
"No manifest capacity in IncrementalSuffixStrategy.");
}
void reset(std::uint32_t offset = 0) override { next_suffix_ = offset; }
protected:
std::uint32_t next_suffix_;
};
class CapacityBasedSuffixStrategy : public SuffixStrategy {
public:
CapacityBasedSuffixStrategy(std::uint32_t start_offset,
std::uint32_t manifest_capacity)
: SuffixStrategy(NextSegmentCalculationStrategy::INCREMENTAL),
next_suffix_(start_offset),
segments_in_manifest_(manifest_capacity),
current_manifest_iteration_(0) {}
TRANSPORT_ALWAYS_INLINE std::uint32_t getNextSuffix() override {
incrementTotalCount();
return next_suffix_++;
}
TRANSPORT_ALWAYS_INLINE std::uint32_t getNextContentSuffix() override {
incrementTotalCount();
return next_suffix_ % segments_in_manifest_ == 0 ? next_suffix_++
: ++next_suffix_;
}
TRANSPORT_ALWAYS_INLINE std::uint32_t getNextManifestSuffix() override {
incrementTotalCount();
return (current_manifest_iteration_++) * (segments_in_manifest_ + 1);
}
TRANSPORT_ALWAYS_INLINE uint32_t getManifestCapacity() override {
return segments_in_manifest_;
}
TRANSPORT_ALWAYS_INLINE void setManifestCapacity(uint32_t capacity) override {
segments_in_manifest_ = capacity;
}
void reset(std::uint32_t offset = 0) override { next_suffix_ = offset; }
protected:
std::uint32_t next_suffix_;
std::uint32_t segments_in_manifest_;
std::uint32_t current_manifest_iteration_;
};
class SuffixStrategyFactory {
public:
static std::unique_ptr<SuffixStrategy> getSuffixStrategy(
NextSegmentCalculationStrategy strategy, uint32_t start_offset,
uint32_t manifest_capacity = 0) {
switch (strategy) {
case NextSegmentCalculationStrategy::INCREMENTAL:
return std::make_unique<IncrementalSuffixStrategy>(start_offset);
case NextSegmentCalculationStrategy::MANIFEST_CAPACITY_BASED:
return std::make_unique<CapacityBasedSuffixStrategy>(start_offset,
manifest_capacity);
default:
throw errors::RuntimeException(
"No valid NextSegmentCalculationStrategy specified.");
}
}
};
} // namespace utils
|
