1/*
2 * Copyright (C) 2017 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 "perfetto/tracing/core/trace_packet.h"
18
19#include "perfetto/base/logging.h"
20#include "perfetto/protozero/proto_utils.h"
21#include "src/tracing/core/sliced_protobuf_input_stream.h"
22
23namespace perfetto {
24
25TracePacket::TracePacket() = default;
26TracePacket::~TracePacket() = default;
27
28TracePacket::TracePacket(TracePacket&& other) noexcept {
29  *this = std::move(other);
30}
31
32TracePacket& TracePacket::operator=(TracePacket&& other) {
33  slices_ = std::move(other.slices_);
34  other.slices_.clear();
35  size_ = other.size_;
36  other.size_ = 0;
37  return *this;
38}
39
40void TracePacket::AddSlice(Slice slice) {
41  size_ += slice.size;
42  slices_.push_back(std::move(slice));
43}
44
45void TracePacket::AddSlice(const void* start, size_t size) {
46  size_ += size;
47  slices_.emplace_back(start, size);
48}
49
50std::tuple<char*, size_t> TracePacket::GetProtoPreamble() {
51  using protozero::proto_utils::MakeTagLengthDelimited;
52  using protozero::proto_utils::WriteVarInt;
53  uint8_t* ptr = reinterpret_cast<uint8_t*>(&preamble_[0]);
54
55  constexpr uint8_t tag = MakeTagLengthDelimited(kPacketFieldNumber);
56  static_assert(tag < 0x80, "TracePacket tag should fit in one byte");
57  *(ptr++) = tag;
58
59  ptr = WriteVarInt(size(), ptr);
60  size_t preamble_size = reinterpret_cast<uintptr_t>(ptr) -
61                         reinterpret_cast<uintptr_t>(&preamble_[0]);
62  PERFETTO_DCHECK(preamble_size <= sizeof(preamble_));
63  return std::make_tuple(&preamble_[0], preamble_size);
64}
65
66std::unique_ptr<TracePacket::ZeroCopyInputStream>
67TracePacket::CreateSlicedInputStream() const {
68  return std::unique_ptr<ZeroCopyInputStream>(
69      new SlicedProtobufInputStream(&slices_));
70}
71
72}  // namespace perfetto
73