arc: enable Android tracing in verified-boot mode

chrome/browser/chromeos/arc/trace/arc_trace_reader.h

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_BROWSER_CHROMEOS_ARC_TRACE_ARC_TRACE_READER_H_
+#define CHROME_BROWSER_CHROMEOS_ARC_TRACE_ARC_TRACE_READER_H_
+
+#include <inttypes.h>
+
+#include <memory>
+#include <queue>
+#include <string>
+
+#include "base/files/scoped_file.h"
+#include "base/macros.h"
+#include "base/threading/simple_thread.h"
+#include "chromeos/trace/arc_trace_agent.h"
+
+namespace arc {
+
+// The class is for reading ARC trace data from the given socket FD, transform
+// data into the JSON format, and store it in a circular buffer.
+class ArcTraceReader : public base::DelegateSimpleThread::Delegate {
+ public:
+  using StopTracingCallback =
+      chromeos::ArcTraceAgent::Delegate::StopTracingCallback;
+
+  ArcTraceReader();
+
+  // Sets the input socket FD for reading ARC trace data.
+  void SetInputFD(base::ScopedFD fd);
+
+  void StartRecord();
+
+  void StopRecord(const StopTracingCallback& callback);
+
+  // DelegateSimpleThread::Delegate overrides:
+  void Run() override;
+
+ private:
+  void WriteTraceEvent(char ph,
+                       int pid,
+                       int tid,
+                       uint64_t ts,
+                       uint64_t tts,
+                       const std::string* name = nullptr,
+                       const int* count = nullptr,
+                       const int* id = nullptr);
+
+  void ParseAndSaveData(std::string data);
+
+  bool is_recording_;
+  std::queue<std::string> trace_buffer_;
+  int current_data_size_;
+  base::ScopedFD input_fd_;
+  // Thread used for reading data from the input socket.
+  std::unique_ptr<base::SimpleThread> recording_thread_;
+
+  DISALLOW_COPY_AND_ASSIGN(ArcTraceReader);
+};
+
+}  // namespace arc
+
+#endif  // CHROME_BROWSER_CHROMEOS_ARC_TRACE_ARC_TRACE_READER_H_