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 "tools/ftrace_proto_gen/ftrace_descriptor_gen.h"
18 
19 namespace perfetto {
20 
GenerateFtraceDescriptors(const google::protobuf::DescriptorPool & descriptor_pool,std::ostream * fout)21 void GenerateFtraceDescriptors(
22     const google::protobuf::DescriptorPool& descriptor_pool,
23     std::ostream* fout) {
24   const google::protobuf::Descriptor* ftrace_event =
25       descriptor_pool.FindMessageTypeByName("perfetto.protos.FtraceEvent");
26   const google::protobuf::OneofDescriptor* one_of_event =
27       ftrace_event->FindOneofByName("event");
28 
29   // Find max id for any ftrace event.
30   int max_id = 0;
31   for (int i = 0; i < one_of_event->field_count(); i++)
32     max_id = std::max(max_id, one_of_event->field(i)->number());
33 
34   *fout << "// Autogenerated by:\n";
35   *fout << std::string("// ") + __FILE__ + "\n";
36   *fout << "// Do not edit.\n";
37   *fout << R"(
38   #include "src/trace_processor/ftrace_descriptors.h"
39 
40   namespace perfetto {
41   namespace trace_processor {
42   namespace {
43 
44   std::array<MessageDescriptor,
45   )";
46   *fout << std::to_string(max_id + 1) + "> descriptors{{";
47 
48   for (int i = 0; i <= max_id; i++) {
49     const google::protobuf::FieldDescriptor* event =
50         ftrace_event->FindFieldByNumber(i);
51     // Skip events that don't exist or are not messages. (Proxy for events)
52     if (!event ||
53         event->type() != google::protobuf::FieldDescriptor::TYPE_MESSAGE) {
54       *fout << "{nullptr, 0, {}},";
55       continue;
56     }
57 
58     const auto* event_descriptor = event->message_type();
59 
60     // Find the max field id in the event.
61     int max_field_id = 0;
62     for (int j = 0; j < event_descriptor->field_count(); j++)
63       max_field_id =
64           std::max(max_field_id, event_descriptor->field(j)->number());
65 
66     *fout << "{\"" + event->name() + "\", " << max_field_id << ", "
67           << "{";
68 
69     for (int j = 0; j <= max_field_id; j++) {
70       const auto* field = event_descriptor->FindFieldByNumber(j);
71       // Skip fields that don't exist or are nested messages.
72       if (!field ||
73           field->type() == google::protobuf::FieldDescriptor::TYPE_MESSAGE) {
74         *fout << "{},";
75         continue;
76       }
77       ProtoType type = ProtoType::FromDescriptor(field->type());
78       *fout << "{\"" + field->name() + "\", ProtoSchemaType::k" +
79                    ToCamelCase(type.ToString()) + "},";
80     }
81     *fout << "},\n},";
82   }
83   *fout << "}};\n";
84   *fout << R"(
85   } // namespace
86 
87   MessageDescriptor* GetMessageDescriptorForId(size_t id) {
88     PERFETTO_CHECK(id < descriptors.size());
89     return &descriptors[id];
90   }
91 
92   size_t GetDescriptorsSize() {
93     return descriptors.size();
94   }
95   )";
96   *fout << "} // namespace trace_processor\n} // namespace perfetto\n";
97 }
98 
99 }  // namespace perfetto
100