chrome/renderer/benchmarking_extension.cc

// Copyright 2011 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "chrome/renderer/benchmarking_extension.h"

#include "base/command_line.h"
#include "base/process/process_handle.h"
#include "base/threading/platform_thread.h"
#include "base/time/time.h"
#include "content/public/common/content_switches.h"
#include "content/public/renderer/render_thread.h"
#include "v8/include/v8-extension.h"
#include "v8/include/v8-primitive.h"
#include "v8/include/v8-template.h"

const char kBenchmarkingExtensionName[] = "v8/Benchmarking";

namespace extensions_v8 {

class BenchmarkingWrapper : public v8::Extension {
 public:
  BenchmarkingWrapper()
      : v8::Extension(kBenchmarkingExtensionName,
                      "if (typeof(chrome) == 'undefined') {"
                      "  chrome = {};"
                      "};"
                      "if (typeof(chrome.benchmarking) == 'undefined') {"
                      "  chrome.benchmarking = {};"
                      "};"
                      "chrome.benchmarking.isSingleProcess = function() {"
                      "  native function IsSingleProcess();"
                      "  return IsSingleProcess();"
                      "};"
                      "chrome.benchmarking.getRendererPid = function() {"
                      "  native function GetRendererPid();"
                      "  return GetRendererPid();"
                      "};"
                      "chrome.benchmarking.getRendererMainTid = function() {"
                      "  native function GetRendererMainTid();"
                      "  return GetRendererMainTid();"
                      "};"
                      "chrome.Interval = function() {"
                      "  var start_ = 0;"
                      "  var stop_ = 0;"
                      "  native function HiResTime();"
                      "  this.start = function() {"
                      "    stop_ = 0;"
                      "    start_ = HiResTime();"
                      "  };"
                      "  this.stop = function() {"
                      "    stop_ = HiResTime();"
                      "    if (start_ == 0)"
                      "      stop_ = 0;"
                      "  };"
                      "  this.microseconds = function() {"
                      "    var stop = stop_;"
                      "    if (stop == 0 && start_ != 0)"
                      "      stop = HiResTime();"
                      "    return Math.ceil(stop - start_);"
                      "  };"
                      "}") {}

  v8::Local<v8::FunctionTemplate> GetNativeFunctionTemplate(
      v8::Isolate* isolate,
      v8::Local<v8::String> name) override {
    if (name->StringEquals(
            v8::String::NewFromUtf8(isolate, "IsSingleProcess",
                                    v8::NewStringType::kInternalized)
                .ToLocalChecked())) {
      return v8::FunctionTemplate::New(isolate, IsSingleProcess);
    } else if (name->StringEquals(
                   v8::String::NewFromUtf8(isolate, "HiResTime",
                                           v8::NewStringType::kInternalized)
                       .ToLocalChecked())) {
      return v8::FunctionTemplate::New(isolate, HiResTime);
    } else if (name->StringEquals(
                   v8::String::NewFromUtf8(isolate, "GetRendererPid",
                                           v8::NewStringType::kInternalized)
                       .ToLocalChecked())) {
      return v8::FunctionTemplate::New(isolate, GetRendererPid);
    } else if (name->StringEquals(
                   v8::String::NewFromUtf8(isolate, "GetRendererMainTid",
                                           v8::NewStringType::kInternalized)
                       .ToLocalChecked())) {
      return v8::FunctionTemplate::New(isolate, GetRendererMainTid);
    }

    return v8::Local<v8::FunctionTemplate>();
  }

  static void IsSingleProcess(const v8::FunctionCallbackInfo<v8::Value>& args) {
    args.GetReturnValue().Set(base::CommandLine::ForCurrentProcess()->HasSwitch(
        switches::kSingleProcess));
  }

  static void HiResTime(const v8::FunctionCallbackInfo<v8::Value>& args) {
    args.GetReturnValue().Set(
        static_cast<double>(base::TimeTicks::Now().ToInternalValue()));
  }

  static void GetRendererPid(const v8::FunctionCallbackInfo<v8::Value>& args) {
    args.GetReturnValue().Set(static_cast<int>(base::GetCurrentProcId()));
  }

  static void GetRendererMainTid(
      const v8::FunctionCallbackInfo<v8::Value>& args) {
    args.GetReturnValue().Set(
        static_cast<int>(base::PlatformThread::CurrentId()));
  }
};

std::unique_ptr<v8::Extension> BenchmarkingExtension::Get() {
  return std::make_unique<BenchmarkingWrapper>();
}

}  // namespace extensions_v8