| /* |
| * Copyright 2014 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "include/utils/SkEventTracer.h" |
| |
| #include "include/private/base/SkOnce.h" |
| |
| #include <stdlib.h> |
| #include <atomic> |
| |
| class SkDefaultEventTracer : public SkEventTracer { |
| SkEventTracer::Handle |
| addTraceEvent(char phase, |
| const uint8_t* categoryEnabledFlag, |
| const char* name, |
| uint64_t id, |
| int numArgs, |
| const char** argNames, |
| const uint8_t* argTypes, |
| const uint64_t* argValues, |
| uint8_t flags) override { return 0; } |
| |
| void |
| updateTraceEventDuration(const uint8_t* categoryEnabledFlag, |
| const char* name, |
| SkEventTracer::Handle handle) override {} |
| |
| const uint8_t* getCategoryGroupEnabled(const char* name) override { |
| static uint8_t no = 0; |
| return &no; |
| } |
| const char* getCategoryGroupName( |
| const uint8_t* categoryEnabledFlag) override { |
| static const char* stub = "stub"; |
| return stub; |
| } |
| |
| // The default tracer does not yet support splitting up trace output into sections. |
| void newTracingSection(const char* name) override {} |
| }; |
| |
| // We prefer gUserTracer if it's been set, otherwise we fall back on a default tracer; |
| static std::atomic<SkEventTracer*> gUserTracer{nullptr}; |
| |
| bool SkEventTracer::SetInstance(SkEventTracer* tracer, bool leakTracer) { |
| SkEventTracer* expected = nullptr; |
| if (!gUserTracer.compare_exchange_strong(expected, tracer)) { |
| delete tracer; |
| return false; |
| } |
| // If leaking the tracer is accepted then there is no need to install |
| // the atexit. |
| if (!leakTracer) { |
| atexit([]() { delete gUserTracer.load(); }); |
| } |
| return true; |
| } |
| |
| SkEventTracer* SkEventTracer::GetInstance() { |
| if (auto tracer = gUserTracer.load(std::memory_order_acquire)) { |
| return tracer; |
| } |
| static SkOnce once; |
| static SkDefaultEventTracer* defaultTracer; |
| once([] { defaultTracer = new SkDefaultEventTracer; }); |
| return defaultTracer; |
| } |