naiveproxy/base/trace_event/auto_open_close_event.h
2018-01-29 00:30:36 +08:00

57 lines
1.8 KiB
C++

// Copyright 2016 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 BASE_AUTO_OPEN_CLOSE_EVENT_H_
#define BASE_AUTO_OPEN_CLOSE_EVENT_H_
#include "base/macros.h"
#include "base/memory/weak_ptr.h"
#include "base/threading/thread_checker.h"
#include "base/time/time.h"
#include "base/trace_event/trace_event.h"
namespace base {
namespace trace_event {
// Class for tracing events that support "auto-opening" and "auto-closing".
// "auto-opening" = if the trace event is started (call Begin() before
// tracing is started,the trace event will be opened, with the start time
// being the time that the trace event was actually started.
// "auto-closing" = if the trace event is started but not ended by the time
// tracing ends, then the trace event will be automatically closed at the
// end of tracing.
class BASE_EXPORT AutoOpenCloseEvent
: public TraceLog::AsyncEnabledStateObserver {
public:
enum Type {
ASYNC
};
// As in the rest of the tracing macros, the const char* arguments here
// must be pointers to indefinitely lived strings (e.g. hard-coded string
// literals are okay, but not strings created by c_str())
AutoOpenCloseEvent(Type type, const char* category, const char* event_name);
~AutoOpenCloseEvent() override;
void Begin();
void End();
// AsyncEnabledStateObserver implementation
void OnTraceLogEnabled() override;
void OnTraceLogDisabled() override;
private:
const char* const category_;
const char* const event_name_;
base::TimeTicks start_time_;
base::ThreadChecker thread_checker_;
WeakPtrFactory<AutoOpenCloseEvent> weak_factory_;
DISALLOW_COPY_AND_ASSIGN(AutoOpenCloseEvent);
};
} // namespace trace_event
} // namespace base
#endif // BASE_AUTO_OPEN_CLOSE_EVENT_H_