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 #ifndef SRC_TRACE_PROCESSOR_IMPORTERS_FTRACE_FTRACE_DESCRIPTORS_H_
18 #define SRC_TRACE_PROCESSOR_IMPORTERS_FTRACE_FTRACE_DESCRIPTORS_H_
19 
20 #include <array>
21 
22 #include "perfetto/ext/base/string_view.h"
23 #include "perfetto/protozero/proto_utils.h"
24 
25 namespace perfetto {
26 namespace trace_processor {
27 
28 using protozero::proto_utils::ProtoSchemaType;
29 
30 // We assume that no ftrace event (e.g. SchedSwitchFtraceEvent) has a proto
31 // field which id is >= this.
32 static constexpr size_t kMaxFtraceEventFields = 32;
33 
34 // This file is the header for the generated descriptors for all ftrace event
35 // protos. These descriptors can be used to parse ftrace event protos without
36 // needing individual parsing logic for every event. (In proto_trace_parser.cc)
37 // By generating these descriptors we avoid having to build the full proto
38 // library. These structs deliberately don't have a ctor (nor are initialized)
39 // because they are used to define linker-initialized dicts in the .cc file.
40 struct FieldDescriptor {
41   const char* name;
42   ProtoSchemaType type;
43 };
44 
45 struct MessageDescriptor {
46   const char* name;
47   size_t max_field_id;
48   FieldDescriptor fields[kMaxFtraceEventFields];
49 };
50 
51 MessageDescriptor* GetMessageDescriptorForId(size_t id);
52 MessageDescriptor* GetMessageDescriptorForName(base::StringView name);
53 size_t GetDescriptorsSize();
54 
55 }  // namespace trace_processor
56 }  // namespace perfetto
57 #endif  // SRC_TRACE_PROCESSOR_IMPORTERS_FTRACE_FTRACE_DESCRIPTORS_H_
58