xref: /aosp_15_r20/external/webrtc/net/dcsctp/packet/error_cause/no_user_data_cause.cc (revision d9f758449e529ab9291ac668be2861e7a55c2422)
1 /*
2  *  Copyright (c) 2021 The WebRTC project authors. All Rights Reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 #include "net/dcsctp/packet/error_cause/no_user_data_cause.h"
11 
12 #include <stdint.h>
13 
14 #include <string>
15 #include <type_traits>
16 #include <vector>
17 
18 #include "absl/types/optional.h"
19 #include "api/array_view.h"
20 #include "net/dcsctp/packet/bounded_byte_reader.h"
21 #include "net/dcsctp/packet/bounded_byte_writer.h"
22 #include "net/dcsctp/packet/tlv_trait.h"
23 #include "rtc_base/strings/string_builder.h"
24 
25 namespace dcsctp {
26 
27 // https://tools.ietf.org/html/rfc4960#section-3.3.10.9
28 
29 //  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
30 //  |     Cause Code=9              |      Cause Length=8           |
31 //  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
32 //  /                  TSN value                                    /
33 //  \                                                               \
34 //  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
35 constexpr int NoUserDataCause::kType;
36 
Parse(rtc::ArrayView<const uint8_t> data)37 absl::optional<NoUserDataCause> NoUserDataCause::Parse(
38     rtc::ArrayView<const uint8_t> data) {
39   absl::optional<BoundedByteReader<kHeaderSize>> reader = ParseTLV(data);
40   if (!reader.has_value()) {
41     return absl::nullopt;
42   }
43   TSN tsn(reader->Load32<4>());
44   return NoUserDataCause(tsn);
45 }
46 
SerializeTo(std::vector<uint8_t> & out) const47 void NoUserDataCause::SerializeTo(std::vector<uint8_t>& out) const {
48   BoundedByteWriter<kHeaderSize> writer = AllocateTLV(out);
49   writer.Store32<4>(*tsn_);
50 }
51 
ToString() const52 std::string NoUserDataCause::ToString() const {
53   rtc::StringBuilder sb;
54   sb << "No User Data, tsn=" << *tsn_;
55   return sb.Release();
56 }
57 }  // namespace dcsctp
58