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
23 namespace perfetto {
24
25 TracePacket::TracePacket() = default;
26 TracePacket::~TracePacket() = default;
27
TracePacket(TracePacket && other)28 TracePacket::TracePacket(TracePacket&& other) noexcept {
29 *this = std::move(other);
30 }
31
operator =(TracePacket && other)32 TracePacket& 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
AddSlice(Slice slice)40 void TracePacket::AddSlice(Slice slice) {
41 size_ += slice.size;
42 slices_.push_back(std::move(slice));
43 }
44
AddSlice(const void * start,size_t size)45 void TracePacket::AddSlice(const void* start, size_t size) {
46 size_ += size;
47 slices_.emplace_back(start, size);
48 }
49
GetProtoPreamble()50 std::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
66 std::unique_ptr<TracePacket::ZeroCopyInputStream>
CreateSlicedInputStream() const67 TracePacket::CreateSlicedInputStream() const {
68 return std::unique_ptr<ZeroCopyInputStream>(
69 new SlicedProtobufInputStream(&slices_));
70 }
71
72 } // namespace perfetto
73