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/iterator.h"
18
19 #include "os/log.h"
20
21 namespace bluetooth {
22 namespace packet {
23
24 template <bool little_endian>
Iterator(const std::forward_list<View> & data,size_t offset)25 Iterator<little_endian>::Iterator(const std::forward_list<View>& data, size_t offset) {
26 data_ = data;
27 index_ = offset;
28 begin_ = 0;
29 end_ = 0;
30 for (auto& view : data) {
31 end_ += view.size();
32 }
33 }
34
35 template <bool little_endian>
operator +(int offset) const36 Iterator<little_endian> Iterator<little_endian>::operator+(int offset) const {
37 auto itr(*this);
38
39 return itr += offset;
40 }
41
42 template <bool little_endian>
operator +=(int offset)43 Iterator<little_endian>& Iterator<little_endian>::operator+=(int offset) {
44 index_ += offset;
45 return *this;
46 }
47
48 template <bool little_endian>
operator ++()49 Iterator<little_endian>& Iterator<little_endian>::operator++() {
50 index_++;
51 return *this;
52 }
53
54 template <bool little_endian>
operator -(int offset) const55 Iterator<little_endian> Iterator<little_endian>::operator-(int offset) const {
56 auto itr(*this);
57
58 return itr -= offset;
59 }
60
61 template <bool little_endian>
operator -(const Iterator<little_endian> & itr) const62 int Iterator<little_endian>::operator-(const Iterator<little_endian>& itr) const {
63 return index_ - itr.index_;
64 }
65
66 template <bool little_endian>
operator -=(int offset)67 Iterator<little_endian>& Iterator<little_endian>::operator-=(int offset) {
68 index_ -= offset;
69
70 return *this;
71 }
72
73 template <bool little_endian>
operator --()74 Iterator<little_endian>& Iterator<little_endian>::operator--() {
75 if (index_ != 0) {
76 index_--;
77 }
78 return *this;
79 }
80
81 template <bool little_endian>
operator =(const Iterator<little_endian> & itr)82 Iterator<little_endian>& Iterator<little_endian>::operator=(const Iterator<little_endian>& itr) {
83 if (this == &itr) {
84 return *this;
85 }
86 this->data_ = itr.data_;
87 this->begin_ = itr.begin_;
88 this->end_ = itr.end_;
89 this->index_ = itr.index_;
90 return *this;
91 }
92
93 template <bool little_endian>
operator ==(const Iterator<little_endian> & itr) const94 bool Iterator<little_endian>::operator==(const Iterator<little_endian>& itr) const {
95 return index_ == itr.index_;
96 }
97
98 template <bool little_endian>
operator !=(const Iterator<little_endian> & itr) const99 bool Iterator<little_endian>::operator!=(const Iterator<little_endian>& itr) const {
100 return !(*this == itr);
101 }
102
103 template <bool little_endian>
operator <(const Iterator<little_endian> & itr) const104 bool Iterator<little_endian>::operator<(const Iterator<little_endian>& itr) const {
105 return index_ < itr.index_;
106 }
107
108 template <bool little_endian>
operator >(const Iterator<little_endian> & itr) const109 bool Iterator<little_endian>::operator>(const Iterator<little_endian>& itr) const {
110 return index_ > itr.index_;
111 }
112
113 template <bool little_endian>
operator <=(const Iterator<little_endian> & itr) const114 bool Iterator<little_endian>::operator<=(const Iterator<little_endian>& itr) const {
115 return index_ <= itr.index_;
116 }
117
118 template <bool little_endian>
operator >=(const Iterator<little_endian> & itr) const119 bool Iterator<little_endian>::operator>=(const Iterator<little_endian>& itr) const {
120 return index_ >= itr.index_;
121 }
122
123 template <bool little_endian>
operator *() const124 uint8_t Iterator<little_endian>::operator*() const {
125 ASSERT_LOG(
126 NumBytesRemaining() > 0,
127 "Index %zu out of bounds: [%zu,%zu)",
128 index_,
129 begin_,
130 end_);
131 size_t index = index_;
132
133 for (auto view : data_) {
134 if (index < view.size()) {
135 return view[index];
136 }
137 index -= view.size();
138 }
139 ASSERT_LOG(false, "Out of fragments searching for index %zu", index_);
140 return 0;
141 }
142
143 template <bool little_endian>
NumBytesRemaining() const144 size_t Iterator<little_endian>::NumBytesRemaining() const {
145 if (end_ > index_ && index_ >= begin_) {
146 return end_ - index_;
147 }
148 return 0;
149 }
150
151 template <bool little_endian>
Subrange(size_t index,size_t length) const152 Iterator<little_endian> Iterator<little_endian>::Subrange(size_t index, size_t length) const {
153 Iterator<little_endian> to_return(*this);
154 if (to_return.NumBytesRemaining() > index) {
155 to_return.index_ = to_return.index_ + index;
156 to_return.begin_ = to_return.index_;
157 if (to_return.NumBytesRemaining() >= length) {
158 to_return.end_ = to_return.index_ + length;
159 }
160 } else {
161 to_return.end_ = 0;
162 }
163
164 return to_return;
165 }
166
167 // Explicit instantiations for both types of Iterators.
168 template class Iterator<true>;
169 template class Iterator<false>;
170 } // namespace packet
171 } // namespace bluetooth
172