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
21class SK_API SkEventTracer {
22public:
23
24 typedef uint64_t Handle;
25
26 /**
27 * If this is the first call to SetInstance or GetInstance then the passed instance is
28 * installed and true is returned. Otherwise, false is returned. In either case ownership of the
29 * tracer is transferred and it will be deleted when no longer needed.
30 */
31 static bool SetInstance(SkEventTracer*);
32
33 /**
34 * Gets the event tracer. If this is the first call to SetInstance or GetIntance then a default
35 * event tracer is installed and returned.
36 */
37 static SkEventTracer* GetInstance();
38
39 virtual ~SkEventTracer() { }
40
41 // The pointer returned from GetCategoryGroupEnabled() points to a
42 // value with zero or more of the following bits. Used in this class only.
43 // The TRACE_EVENT macros should only use the value as a bool.
44 // These values must be in sync with macro values in trace_event.h in chromium.
45 enum CategoryGroupEnabledFlags {
46 // Category group enabled for the recording mode.
47 kEnabledForRecording_CategoryGroupEnabledFlags = 1 << 0,
48 // Category group enabled for the monitoring mode.
49 kEnabledForMonitoring_CategoryGroupEnabledFlags = 1 << 1,
50 // Category group enabled by SetEventCallbackEnabled().
51 kEnabledForEventCallback_CategoryGroupEnabledFlags = 1 << 2,
52 };
53
54 virtual const uint8_t* getCategoryGroupEnabled(const char* name) = 0;
55 virtual const char* getCategoryGroupName(const uint8_t* categoryEnabledFlag) = 0;
56
57 virtual SkEventTracer::Handle
58 addTraceEvent(char phase,
59 const uint8_t* categoryEnabledFlag,
60 const char* name,
61 uint64_t id,
62 int32_t numArgs,
63 const char** argNames,
64 const uint8_t* argTypes,
65 const uint64_t* argValues,
66 uint8_t flags) = 0;
67
68 virtual void
69 updateTraceEventDuration(const uint8_t* categoryEnabledFlag,
70 const char* name,
71 SkEventTracer::Handle handle) = 0;
72};
73
74#endif // SkEventTracer_DEFINED
75