1// Copyright 2014 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef NET_BASE_TRACE_NET_LOG_OBSERVER_H_
6#define NET_BASE_TRACE_NET_LOG_OBSERVER_H_
7
8#include "base/debug/trace_event_impl.h"
9#include "base/macros.h"
10#include "net/base/net_export.h"
11#include "net/base/net_log.h"
12
13namespace net {
14
15// TraceNetLogObserver watches for TraceLog enable, and sends NetLog
16// events to TraceLog if it is enabled.
17class NET_EXPORT TraceNetLogObserver
18    : public NetLog::ThreadSafeObserver,
19      public base::debug::TraceLog::EnabledStateObserver {
20 public:
21  TraceNetLogObserver();
22  virtual ~TraceNetLogObserver();
23
24  // net::NetLog::ThreadSafeObserver implementation:
25  virtual void OnAddEntry(const NetLog::Entry& entry) OVERRIDE;
26
27  // Start to watch for TraceLog enable and disable events.
28  // This can't be called if already watching for events.
29  // Watches NetLog only when tracing is enabled.
30  void WatchForTraceStart(NetLog* net_log);
31
32  // Stop watching for TraceLog enable and disable events.
33  // If WatchForTraceStart is called, this must be called before
34  // TraceNetLogObserver is destroyed.
35  void StopWatchForTraceStart();
36
37  // base::debug::TraceLog::EnabledStateChangedObserver implementation:
38  virtual void OnTraceLogEnabled() OVERRIDE;
39  virtual void OnTraceLogDisabled() OVERRIDE;
40
41 private:
42  NetLog* net_log_to_watch_;
43
44  DISALLOW_COPY_AND_ASSIGN(TraceNetLogObserver);
45};
46
47}  // namespace net
48
49#endif  // NET_BASE_TRACE_NET_LOG_OBSERVER_H_
50