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 COMPONENTS_FEEDBACK_TRACING_MANAGER_H_ 6 #define COMPONENTS_FEEDBACK_TRACING_MANAGER_H_ 7 8 #include <map> 9 #include <string> 10 11 #include "base/basictypes.h" 12 #include "base/callback.h" 13 #include "base/memory/scoped_ptr.h" 14 #include "base/memory/weak_ptr.h" 15 16 namespace base { 17 18 class RefCountedString; 19 class FilePath; 20 21 } 22 // Callback used for getting the output of a trace. 23 typedef base::Callback<void(scoped_refptr<base::RefCountedString> trace_data)> 24 TraceDataCallback; 25 26 // This class is used to manage performance metrics that can be attached to 27 // feedback reports. This class is a Singleton that is owned by the preference 28 // system. It should only be created when it is enabled, and should only be 29 // accessed elsewhere via Get(). 30 // 31 // When a performance trace is desired, TracingManager::Get()->RequestTrace() 32 // should be invoked. The TracingManager will then start preparing a zipped 33 // version of the performance data. That data can then be requested via 34 // GetTraceData(). When the data is no longer needed, it should be discarded 35 // via DiscardTraceData(). 36 class TracingManager { 37 public: 38 virtual ~TracingManager(); 39 40 // Create a TracingManager. Can only be called when none exists. 41 static scoped_ptr<TracingManager> Create(); 42 43 // Get the current TracingManager. Returns NULL if one doesn't exist. 44 static TracingManager* Get(); 45 46 // Request a trace ending at the current time. If a trace is already being 47 // collected, the id for that trace is returned. 48 int RequestTrace(); 49 50 // Get the trace data for |id|. On success, true is returned, and the data is 51 // returned via |callback|. Returns false on failure. 52 bool GetTraceData(int id, const TraceDataCallback& callback); 53 54 // Discard the data for trace |id|. 55 void DiscardTraceData(int id); 56 57 private: 58 TracingManager(); 59 60 void StartTracing(); 61 void OnTraceDataCollected(base::RefCountedString* data); 62 63 // ID of the trace that is being collected. 64 int current_trace_id_; 65 66 // Mapping of trace ID to trace data. 67 std::map<int, scoped_refptr<base::RefCountedString> > trace_data_; 68 69 // Callback for the current trace request. 70 TraceDataCallback trace_callback_; 71 72 base::WeakPtrFactory<TracingManager> weak_ptr_factory_; 73 74 DISALLOW_COPY_AND_ASSIGN(TracingManager); 75 }; 76 77 #endif // COMPONENTS_FEEDBACK_TRACING_MANAGER_H_ 78 79