1 /*
2 * Copyright 2018 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_view.h"
18
19 #include <algorithm>
20
21 #include <base/logging.h>
22
23 namespace test_vendor_lib {
24 namespace packets {
25
26 template <bool little_endian>
PacketView(const std::forward_list<class View> fragments)27 PacketView<little_endian>::PacketView(const std::forward_list<class View> fragments)
28 : fragments_(fragments), length_(0) {
29 for (auto fragment : fragments_) {
30 length_ += fragment.size();
31 }
32 }
33
34 template <bool little_endian>
PacketView(std::shared_ptr<std::vector<uint8_t>> packet)35 PacketView<little_endian>::PacketView(std::shared_ptr<std::vector<uint8_t>> packet)
36 : fragments_({View(packet, 0, packet->size())}), length_(packet->size()) {}
37
38 template <bool little_endian>
begin() const39 Iterator<little_endian> PacketView<little_endian>::begin() const {
40 return Iterator<little_endian>(this->fragments_, 0);
41 }
42
43 template <bool little_endian>
end() const44 Iterator<little_endian> PacketView<little_endian>::end() const {
45 return Iterator<little_endian>(this->fragments_, size());
46 }
47
48 template <bool little_endian>
operator [](size_t index) const49 uint8_t PacketView<little_endian>::operator[](size_t index) const {
50 return at(index);
51 }
52
53 template <bool little_endian>
at(size_t index) const54 uint8_t PacketView<little_endian>::at(size_t index) const {
55 CHECK(index < length_) << "Index " << index << " out of bounds";
56 for (const auto& fragment : fragments_) {
57 if (index < fragment.size()) {
58 return fragment[index];
59 }
60 index -= fragment.size();
61 }
62 CHECK(false) << "Out of fragments searching for Index " << index;
63 return 0;
64 }
65
66 template <bool little_endian>
size() const67 size_t PacketView<little_endian>::size() const {
68 return length_;
69 }
70
71 template <bool little_endian>
SubViewList(size_t begin,size_t end) const72 std::forward_list<View> PacketView<little_endian>::SubViewList(size_t begin, size_t end) const {
73 CHECK(begin <= end) << "Begin " << begin << " is past end";
74 CHECK(end <= length_) << "End " << end << " is too large";
75 std::forward_list<View> view_list;
76 std::forward_list<View>::iterator it = view_list.before_begin();
77 size_t length = end - begin;
78 for (const auto& fragment : fragments_) {
79 if (begin >= fragment.size()) {
80 begin -= fragment.size();
81 } else {
82 View view(fragment, begin, begin + std::min(length, fragment.size() - begin));
83 length -= view.size();
84 it = view_list.insert_after(it, view);
85 begin = 0;
86 }
87 }
88 return view_list;
89 }
90
91 template <bool little_endian>
SubViewLittleEndian(size_t begin,size_t end) const92 PacketView<true> PacketView<little_endian>::SubViewLittleEndian(size_t begin, size_t end) const {
93 return PacketView<true>(SubViewList(begin, end));
94 }
95
96 template <bool little_endian>
SubViewBigEndian(size_t begin,size_t end) const97 PacketView<false> PacketView<little_endian>::SubViewBigEndian(size_t begin, size_t end) const {
98 return PacketView<false>(SubViewList(begin, end));
99 }
100
101 // Explicit instantiations for both types of PacketViews.
102 template class PacketView<true>;
103 template class PacketView<false>;
104
105 } // namespace packets
106 } // namespace test_vendor_lib
107