1 /*
2 * Copyright (C) 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 "src/tracing/test/fake_packet.h"
18
19 #include <ostream>
20
21 #include "perfetto/base/logging.h"
22 #include "perfetto/protozero/proto_utils.h"
23 #include "perfetto/tracing/core/shared_memory_abi.h"
24 #include "src/tracing/core/trace_buffer.h"
25
26 using protozero::proto_utils::ParseVarInt;
27 using protozero::proto_utils::WriteVarInt;
28
29 namespace perfetto {
30
FakePacketFragment(size_t size,char prefix)31 FakePacketFragment::FakePacketFragment(size_t size, char prefix) {
32 // |size| has to be at least == 2, because one byte will be taken just by the
33 // varint header.
34 PERFETTO_CHECK(size > 1);
35
36 // Finding the |payload_size| from |size| is quite tricky:
37 // A packet with 127 bytes of payload requires:
38 // 1B header (to represent the number 127 in varint) + 127 = 128 bytes.
39 // A packet with 128 bytes payload requires:
40 // 2B header (to represent the number 128 in varint) + 128 = 130 bytes.
41 // So the only way to generate a packet of 129 bytes in total we need to
42 // generate a redundant varint header of 2 bytes + 127 bytes of payload.
43 if (size <= 128) {
44 header_[0] = static_cast<uint8_t>(size - 1);
45 header_size_ = 1;
46 payload_.resize(size - 1);
47 } else if (size == 129) {
48 header_[0] = 0x80 | 127;
49 header_size_ = 2;
50 payload_.resize(127);
51 } else {
52 WriteVarInt(size - 2, &header_[0]);
53 header_size_ = 2;
54 payload_.resize(size - 2);
55 }
56 // Fills the payload as follow: X00-X01-X02 (where X == |prefix|);
57 for (size_t i = 0; i < payload_.size(); i++) {
58 switch (i % 4) {
59 case 0:
60 payload_[i] = prefix;
61 break;
62 case 1:
63 payload_[i] = '0' + ((i / 4 / 10) % 10);
64 break;
65 case 2:
66 payload_[i] = '0' + ((i / 4) % 10);
67 break;
68 case 3:
69 payload_[i] = '-';
70 break;
71 }
72 }
73 }
74
FakePacketFragment(const void * payload,size_t payload_size)75 FakePacketFragment::FakePacketFragment(const void* payload,
76 size_t payload_size) {
77 PERFETTO_CHECK(payload_size <= 4096 - 2);
78 payload_.assign(reinterpret_cast<const char*>(payload), payload_size);
79 uint8_t* end = WriteVarInt(payload_.size(), &header_[0]);
80 header_size_ = static_cast<size_t>(end - &header_[0]);
81 }
82
CopyInto(std::vector<uint8_t> * data) const83 void FakePacketFragment::CopyInto(std::vector<uint8_t>* data) const {
84 data->insert(data->end(), &header_[0], &header_[0] + header_size_);
85 data->insert(data->end(), payload_.begin(), payload_.end());
86 }
87
GetSizeHeader() const88 size_t FakePacketFragment::GetSizeHeader() const {
89 uint64_t size = 0;
90 ParseVarInt(&header_[0], &header_[0] + header_size_, &size);
91 return static_cast<size_t>(size);
92 }
93
operator ==(const FakePacketFragment & o) const94 bool FakePacketFragment::operator==(const FakePacketFragment& o) const {
95 if (payload_ != o.payload_)
96 return false;
97 PERFETTO_CHECK(GetSizeHeader() == o.GetSizeHeader());
98 return true;
99 }
100
operator <<(std::ostream & os,const FakePacketFragment & packet)101 std::ostream& operator<<(std::ostream& os, const FakePacketFragment& packet) {
102 return os << "{len:" << packet.payload().size() << ", payload:\""
103 << packet.payload() << "\"}";
104 }
105
FakeChunk(TraceBuffer * t,ProducerID p,WriterID w,ChunkID c)106 FakeChunk::FakeChunk(TraceBuffer* t, ProducerID p, WriterID w, ChunkID c)
107 : trace_buffer_{t}, producer_id{p}, writer_id{w}, chunk_id{c} {}
108
AddPacket(size_t size,char seed,uint8_t packet_flag)109 FakeChunk& FakeChunk::AddPacket(size_t size, char seed, uint8_t packet_flag) {
110 PERFETTO_DCHECK(size <= 4096);
111 PERFETTO_CHECK(
112 !(packet_flag &
113 SharedMemoryABI::ChunkHeader::kFirstPacketContinuesFromPrevChunk) ||
114 num_packets == 0);
115 PERFETTO_CHECK(
116 !(flags & SharedMemoryABI::ChunkHeader::kLastPacketContinuesOnNextChunk));
117 flags |= packet_flag;
118 FakePacketFragment(size, seed).CopyInto(&data);
119 num_packets++;
120 return *this;
121 }
122
AddPacket(std::initializer_list<uint8_t> raw)123 FakeChunk& FakeChunk::AddPacket(std::initializer_list<uint8_t> raw) {
124 data.insert(data.end(), raw.begin(), raw.end());
125 num_packets++;
126 return *this;
127 }
128
IncrementNumPackets()129 FakeChunk& FakeChunk::IncrementNumPackets() {
130 num_packets++;
131 return *this;
132 }
133
ClearBytes(size_t offset,size_t len)134 FakeChunk& FakeChunk::ClearBytes(size_t offset, size_t len) {
135 PERFETTO_DCHECK(offset + len <= data.size());
136 memset(data.data() + offset, 0, len);
137 return *this;
138 }
139
SetUID(uid_t u)140 FakeChunk& FakeChunk::SetUID(uid_t u) {
141 uid = u;
142 return *this;
143 }
144
CopyIntoTraceBuffer()145 size_t FakeChunk::CopyIntoTraceBuffer() {
146 trace_buffer_->CopyChunkUntrusted(producer_id, uid, writer_id, chunk_id,
147 num_packets, flags, data.data(),
148 data.size());
149 return data.size() + TraceBuffer::InlineChunkHeaderSize;
150 }
151
152 } // namespace perfetto
153