1 /* 2 * Copyright (C) 2014 Google Inc. All rights reserved. 3 * 4 * Use of this source code is governed by a BSD-style license that can be 5 * found in the LICENSE file. 6 */ 7 8 #ifndef SkEventTracer_DEFINED 9 #define SkEventTracer_DEFINED 10 11 // The class in this header defines the interface between Skia's internal 12 // tracing macros and an external entity (e.g., Chrome) that will consume them. 13 // Such an entity should subclass SkEventTracer and provide an instance of 14 // that event to SkEventTracer::SetInstance. 15 16 // If you're looking for the tracing macros to instrument Skia itself, those 17 // live in src/core/SkTraceEvent.h 18 19 #include "include/core/SkTypes.h" 20 21 #include <cstdint> 22 23 class SK_API SkEventTracer { 24 public: 25 26 typedef uint64_t Handle; 27 28 /** 29 * If this is the first call to SetInstance or GetInstance then the passed instance is 30 * installed and true is returned. Otherwise, false is returned. In either case ownership of the 31 * tracer is transferred and it will be deleted when no longer needed. 32 * 33 * Not deleting the tracer on process exit should not cause problems as 34 * the whole heap is about to go away with the process. This can also 35 * improve performance by reducing the amount of work needed. 36 * 37 * @param leakTracer Do not delete tracer on process exit. 38 */ 39 static bool SetInstance(SkEventTracer*, bool leakTracer = false); 40 41 /** 42 * Gets the event tracer. If this is the first call to SetInstance or GetIntance then a default 43 * event tracer is installed and returned. 44 */ 45 static SkEventTracer* GetInstance(); 46 47 virtual ~SkEventTracer() = default; 48 49 // The pointer returned from GetCategoryGroupEnabled() points to a 50 // value with zero or more of the following bits. Used in this class only. 51 // The TRACE_EVENT macros should only use the value as a bool. 52 // These values must be in sync with macro values in trace_event.h in chromium. 53 enum CategoryGroupEnabledFlags { 54 // Category group enabled for the recording mode. 55 kEnabledForRecording_CategoryGroupEnabledFlags = 1 << 0, 56 // Category group enabled for the monitoring mode. 57 kEnabledForMonitoring_CategoryGroupEnabledFlags = 1 << 1, 58 // Category group enabled by SetEventCallbackEnabled(). 59 kEnabledForEventCallback_CategoryGroupEnabledFlags = 1 << 2, 60 }; 61 62 virtual const uint8_t* getCategoryGroupEnabled(const char* name) = 0; 63 virtual const char* getCategoryGroupName(const uint8_t* categoryEnabledFlag) = 0; 64 65 virtual SkEventTracer::Handle 66 addTraceEvent(char phase, 67 const uint8_t* categoryEnabledFlag, 68 const char* name, 69 uint64_t id, 70 int32_t numArgs, 71 const char** argNames, 72 const uint8_t* argTypes, 73 const uint64_t* argValues, 74 uint8_t flags) = 0; 75 76 virtual void 77 updateTraceEventDuration(const uint8_t* categoryEnabledFlag, 78 const char* name, 79 SkEventTracer::Handle handle) = 0; 80 81 // Optional method that can be implemented to allow splitting up traces into different sections. newTracingSection(const char *)82 virtual void newTracingSection(const char*) {} 83 84 protected: 85 SkEventTracer() = default; 86 SkEventTracer(const SkEventTracer&) = delete; 87 SkEventTracer& operator=(const SkEventTracer&) = delete; 88 }; 89 90 #endif // SkEventTracer_DEFINED 91