1 /*
2 * Copyright (C) 2024 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/trace_processor/importers/android_bugreport/chunked_line_reader.h"
18
19 #include <cstddef>
20 #include <cstring>
21 #include <utility>
22
23 #include "perfetto/base/status.h"
24 #include "perfetto/ext/base/status_or.h"
25 #include "perfetto/ext/base/string_view.h"
26 #include "perfetto/public/compiler.h"
27 #include "perfetto/trace_processor/trace_blob.h"
28 #include "perfetto/trace_processor/trace_blob_view.h"
29 #include "src/trace_processor/util/status_macros.h"
30
31 namespace perfetto ::trace_processor {
32
33 namespace {
34
Append(const TraceBlobView & head,const TraceBlobView & tail)35 TraceBlobView Append(const TraceBlobView& head, const TraceBlobView& tail) {
36 size_t size = head.size() + tail.size();
37 if (size == 0) {
38 return TraceBlobView();
39 }
40 auto blob = TraceBlob::Allocate(size);
41 memcpy(blob.data(), head.data(), head.size());
42 memcpy(blob.data() + head.size(), tail.data(), tail.size());
43 return TraceBlobView(std::move(blob));
44 }
45
46 struct SpliceResult {
47 // Full line including '\n'. Empty if no full line was found.
48 TraceBlobView line;
49 // Any leftovers
50 TraceBlobView leftovers;
51 };
52
SpliceAtNewLine(TraceBlobView data)53 SpliceResult SpliceAtNewLine(TraceBlobView data) {
54 for (size_t i = 0; i < data.size(); ++i) {
55 if (data.data()[i] == '\n') {
56 return {data.slice_off(0, i), data.slice_off(i + 1, data.size() - i - 1)};
57 }
58 }
59 return {TraceBlobView(), std::move(data)};
60 }
61 } // namespace
62
OnLine(const TraceBlobView & data)63 base::Status ChunkedLineReader::OnLine(const TraceBlobView& data) {
64 return ParseLine(base::StringView(reinterpret_cast<const char*>(data.data()),
65 data.size()));
66 }
67
SpliceLoop(TraceBlobView data)68 base::StatusOr<TraceBlobView> ChunkedLineReader::SpliceLoop(
69 TraceBlobView data) {
70 while (true) {
71 SpliceResult res = SpliceAtNewLine(std::move(data));
72 if (res.line.size() == 0) {
73 return std::move(res.leftovers);
74 }
75 RETURN_IF_ERROR(OnLine(res.line));
76 data = std::move(res.leftovers);
77 }
78 }
79
Parse(TraceBlobView data)80 base::Status ChunkedLineReader::Parse(TraceBlobView data) {
81 if (data.size() == 0) {
82 return base::OkStatus();
83 }
84
85 if (PERFETTO_LIKELY(buffer_.size() == 0)) {
86 ASSIGN_OR_RETURN(buffer_, SpliceLoop(std::move(data)));
87 return base::OkStatus();
88 }
89
90 SpliceResult res = SpliceAtNewLine(std::move(data));
91 if (res.line.size() == 0) {
92 buffer_ = Append(buffer_, res.leftovers);
93 return base::OkStatus();
94 }
95
96 buffer_ = Append(buffer_, res.line);
97 RETURN_IF_ERROR(OnLine(buffer_));
98 ASSIGN_OR_RETURN(buffer_, SpliceLoop(std::move(res.leftovers)));
99 return base::OkStatus();
100 }
101
NotifyEndOfFile()102 base::Status ChunkedLineReader::NotifyEndOfFile() {
103 EndOfStream(base::StringView(reinterpret_cast<const char*>(buffer_.data()),
104 buffer_.size()));
105 return base::OkStatus();
106 }
107
108 } // namespace perfetto::trace_processor
109