1 /*
2  * Copyright 2019 The Android Open Source Project
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 #include "packet/fragmenting_inserter.h"
18 
19 #include <gtest/gtest.h>
20 
21 #include <memory>
22 
23 using bluetooth::packet::FragmentingInserter;
24 using std::vector;
25 
26 namespace bluetooth {
27 namespace packet {
28 
TEST(FragmentingInserterTest,addMoreBits)29 TEST(FragmentingInserterTest, addMoreBits) {
30   std::vector<uint8_t> result = {0b00011101 /* 3 2 1 */, 0b00010101 /* 5 4 */, 0b11100011 /* 7 6 */,
31                                  0b10000000 /* 8 */, 0b10100000 /* filled with 1010 */};
32   std::vector<std::unique_ptr<RawBuilder>> fragments;
33 
34   FragmentingInserter it(result.size(), std::back_insert_iterator(fragments));
35 
36   for (size_t i = 0; i < 9; i++) {
37     it.insert_bits(static_cast<uint8_t>(i), i);
38   }
39   it.insert_bits(static_cast<uint8_t>(0b1010), 4);
40 
41   it.finalize();
42 
43   ASSERT_EQ(1ul, fragments.size());
44 
45   std::vector<uint8_t> bytes;
46   BitInserter bit_inserter(bytes);
47   fragments[0]->Serialize(bit_inserter);
48 
49   ASSERT_EQ(result.size(), bytes.size());
50   for (size_t i = 0; i < bytes.size(); i++) {
51     ASSERT_EQ(result[i], bytes[i]);
52   }
53 }
54 
TEST(FragmentingInserterTest,observerTest)55 TEST(FragmentingInserterTest, observerTest) {
56   std::vector<uint8_t> result = {0b00011101 /* 3 2 1 */, 0b00010101 /* 5 4 */, 0b11100011 /* 7 6 */,
57                                  0b10000000 /* 8 */, 0b10100000 /* filled with 1010 */};
58   std::vector<std::unique_ptr<RawBuilder>> fragments;
59 
60   FragmentingInserter it(result.size() + 1, std::back_insert_iterator(fragments));
61 
62   std::vector<uint8_t> copy;
63 
64   uint64_t checksum = 0x0123456789abcdef;
65   it.RegisterObserver(ByteObserver([&copy](uint8_t byte) { copy.push_back(byte); },
66                                    [checksum]() { return checksum; }));
67 
68   for (size_t i = 0; i < 9; i++) {
69     it.insert_bits(static_cast<uint8_t>(i), i);
70   }
71   it.insert_bits(static_cast<uint8_t>(0b1010), 4);
72   it.finalize();
73 
74   ASSERT_EQ(1ul, fragments.size());
75 
76   std::vector<uint8_t> bytes;
77   BitInserter bit_inserter(bytes);
78   fragments[0]->Serialize(bit_inserter);
79 
80   ASSERT_EQ(result.size(), bytes.size());
81   for (size_t i = 0; i < bytes.size(); i++) {
82     ASSERT_EQ(result[i], bytes[i]);
83   }
84 
85   ASSERT_EQ(result.size(), copy.size());
86   for (size_t i = 0; i < copy.size(); i++) {
87     ASSERT_EQ(result[i], copy[i]);
88   }
89 
90   ByteObserver observer = it.UnregisterObserver();
91   ASSERT_EQ(checksum, observer.GetValue());
92 }
93 
TEST(FragmentingInserterTest,testMtuBoundaries)94 TEST(FragmentingInserterTest, testMtuBoundaries) {
95   constexpr size_t kPacketSize = 1024;
96   auto counts = RawBuilder();
97   for (size_t i = 0; i < kPacketSize; i++) {
98     counts.AddOctets1(static_cast<uint8_t>(i));
99   }
100 
101   std::vector<std::unique_ptr<RawBuilder>> fragments_mtu_is_kPacketSize;
102   FragmentingInserter it(kPacketSize, std::back_insert_iterator(fragments_mtu_is_kPacketSize));
103   counts.Serialize(it);
104   it.finalize();
105   ASSERT_EQ(1ul, fragments_mtu_is_kPacketSize.size());
106   ASSERT_EQ(kPacketSize, fragments_mtu_is_kPacketSize[0]->size());
107 
108   std::vector<std::unique_ptr<RawBuilder>> fragments_mtu_is_less;
109   FragmentingInserter it_less(kPacketSize - 1, std::back_insert_iterator(fragments_mtu_is_less));
110   counts.Serialize(it_less);
111   it_less.finalize();
112   ASSERT_EQ(2ul, fragments_mtu_is_less.size());
113   ASSERT_EQ(kPacketSize - 1ul, fragments_mtu_is_less[0]->size());
114   ASSERT_EQ(1ul, fragments_mtu_is_less[1]->size());
115 
116   std::vector<std::unique_ptr<RawBuilder>> fragments_mtu_is_more;
117   FragmentingInserter it_more(kPacketSize + 1, std::back_insert_iterator(fragments_mtu_is_more));
118   counts.Serialize(it_more);
119   it_more.finalize();
120   ASSERT_EQ(1ul, fragments_mtu_is_more.size());
121   ASSERT_EQ(kPacketSize, fragments_mtu_is_more[0]->size());
122 }
123 
124 constexpr size_t kPacketSize = 128;
125 class FragmentingTest : public ::testing::TestWithParam<size_t> {
126 public:
StartUp()127   void StartUp() {
128     counts_.reserve(kPacketSize);
129     for (size_t i = 0; i < kPacketSize; i++) {
130       counts_.push_back(static_cast<uint8_t>(i));
131     }
132   }
ShutDown()133   void ShutDown() { counts_.clear(); }
134   std::vector<uint8_t> counts_;
135 };
136 
TEST_P(FragmentingTest,mtuFragmentTest)137 TEST_P(FragmentingTest, mtuFragmentTest) {
138   size_t mtu = GetParam();
139   std::vector<std::unique_ptr<RawBuilder>> fragments;
140   FragmentingInserter it(mtu, std::back_insert_iterator(fragments));
141 
142   RawBuilder original_packet(counts_);
143   ASSERT_EQ(counts_.size(), original_packet.size());
144 
145   original_packet.Serialize(it);
146   it.finalize();
147 
148   size_t expected_fragments = counts_.size() / mtu;
149   if (counts_.size() % mtu != 0) {
150     expected_fragments++;
151   }
152   ASSERT_EQ(expected_fragments, fragments.size());
153 
154   std::vector<std::vector<uint8_t>> serialized_fragments;
155   for (size_t f = 0; f < fragments.size(); f++) {
156     serialized_fragments.emplace_back(mtu);
157     BitInserter bit_inserter(serialized_fragments[f]);
158     fragments[f]->Serialize(bit_inserter);
159     if (f + 1 == fragments.size() && (counts_.size() % mtu != 0)) {
160       ASSERT_EQ(serialized_fragments[f].size(), counts_.size() % mtu);
161     } else {
162       ASSERT_EQ(serialized_fragments[f].size(), mtu);
163     }
164     for (size_t b = 0; b < serialized_fragments[f].size(); b++) {
165       EXPECT_EQ(counts_[f * mtu + b], serialized_fragments[f][b]);
166     }
167   }
168 }
169 
170 INSTANTIATE_TEST_CASE_P(chopomatic, FragmentingTest, ::testing::Range<size_t>(1, kPacketSize + 1));
171 
172 }  // namespace packet
173 }  // namespace bluetooth
174