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 #undef NDEBUG
20 #include <cassert>
21
22 namespace bluetooth {
23 namespace packet {
24
25 template <bool little_endian>
Iterator(const std::forward_list<View> & data,size_t offset)26 Iterator<little_endian>::Iterator(const std::forward_list<View>& data, size_t offset) {
27 data_ = data;
28 index_ = offset;
29 begin_ = 0;
30 end_ = 0;
31 for (auto& view : data) {
32 end_ += view.size();
33 }
34 }
35
36 template <bool little_endian>
Iterator(std::shared_ptr<std::vector<uint8_t>> data)37 Iterator<little_endian>::Iterator(std::shared_ptr<std::vector<uint8_t>> data) {
38 data_.emplace_front(data, 0, data->size());
39 index_ = 0;
40 begin_ = 0;
41 end_ = data_.front().size();
42 }
43
44 template <bool little_endian>
operator +(int offset) const45 Iterator<little_endian> Iterator<little_endian>::operator+(int offset) const {
46 auto itr(*this);
47
48 return itr += offset;
49 }
50
51 template <bool little_endian>
operator +=(int offset)52 Iterator<little_endian>& Iterator<little_endian>::operator+=(int offset) {
53 index_ += offset;
54 return *this;
55 }
56
57 template <bool little_endian>
operator ++()58 Iterator<little_endian>& Iterator<little_endian>::operator++() {
59 index_++;
60 return *this;
61 }
62
63 template <bool little_endian>
operator -(int offset) const64 Iterator<little_endian> Iterator<little_endian>::operator-(int offset) const {
65 auto itr(*this);
66
67 return itr -= offset;
68 }
69
70 template <bool little_endian>
operator -(const Iterator<little_endian> & itr) const71 int Iterator<little_endian>::operator-(const Iterator<little_endian>& itr) const {
72 return index_ - itr.index_;
73 }
74
75 template <bool little_endian>
operator -=(int offset)76 Iterator<little_endian>& Iterator<little_endian>::operator-=(int offset) {
77 index_ -= offset;
78
79 return *this;
80 }
81
82 template <bool little_endian>
operator --()83 Iterator<little_endian>& Iterator<little_endian>::operator--() {
84 if (index_ != 0) {
85 index_--;
86 }
87 return *this;
88 }
89
90 template <bool little_endian>
operator =(const Iterator<little_endian> & itr)91 Iterator<little_endian>& Iterator<little_endian>::operator=(const Iterator<little_endian>& itr) {
92 if (this == &itr) {
93 return *this;
94 }
95 this->data_ = itr.data_;
96 this->begin_ = itr.begin_;
97 this->end_ = itr.end_;
98 this->index_ = itr.index_;
99 return *this;
100 }
101
102 template <bool little_endian>
operator ==(const Iterator<little_endian> & itr) const103 bool Iterator<little_endian>::operator==(const Iterator<little_endian>& itr) const {
104 return index_ == itr.index_;
105 }
106
107 template <bool little_endian>
operator !=(const Iterator<little_endian> & itr) const108 bool Iterator<little_endian>::operator!=(const Iterator<little_endian>& itr) const {
109 return !(*this == itr);
110 }
111
112 template <bool little_endian>
operator <(const Iterator<little_endian> & itr) const113 bool Iterator<little_endian>::operator<(const Iterator<little_endian>& itr) const {
114 return index_ < itr.index_;
115 }
116
117 template <bool little_endian>
operator >(const Iterator<little_endian> & itr) const118 bool Iterator<little_endian>::operator>(const Iterator<little_endian>& itr) const {
119 return index_ > itr.index_;
120 }
121
122 template <bool little_endian>
operator <=(const Iterator<little_endian> & itr) const123 bool Iterator<little_endian>::operator<=(const Iterator<little_endian>& itr) const {
124 return index_ <= itr.index_;
125 }
126
127 template <bool little_endian>
operator >=(const Iterator<little_endian> & itr) const128 bool Iterator<little_endian>::operator>=(const Iterator<little_endian>& itr) const {
129 return index_ >= itr.index_;
130 }
131
132 template <bool little_endian>
operator *() const133 uint8_t Iterator<little_endian>::operator*() const {
134 assert(NumBytesRemaining() > 0);
135 size_t index = index_;
136
137 for (auto view : data_) {
138 if (index < view.size()) {
139 return view[index];
140 }
141 index -= view.size();
142 }
143
144 // Out of fragments searching for index.
145 std::abort();
146 return 0;
147 }
148
149 template <bool little_endian>
NumBytesRemaining() const150 size_t Iterator<little_endian>::NumBytesRemaining() const {
151 if (end_ > index_ && index_ >= begin_) {
152 return end_ - index_;
153 }
154 return 0;
155 }
156
157 template <bool little_endian>
Subrange(size_t index,size_t length) const158 Iterator<little_endian> Iterator<little_endian>::Subrange(size_t index, size_t length) const {
159 Iterator<little_endian> to_return(*this);
160 if (to_return.NumBytesRemaining() > index) {
161 to_return.index_ = to_return.index_ + index;
162 to_return.begin_ = to_return.index_;
163 if (to_return.NumBytesRemaining() >= length) {
164 to_return.end_ = to_return.index_ + length;
165 }
166 } else {
167 to_return.end_ = 0;
168 }
169
170 return to_return;
171 }
172
173 // Explicit instantiations for both types of Iterators.
174 template class Iterator<true>;
175 template class Iterator<false>;
176 } // namespace packet
177 } // namespace bluetooth
178