toolkit/components/perf/PerfMeasurement.cpp
author Ehsan Akhgari <ehsan@mozilla.com>
Thu, 29 Nov 2018 10:30:46 +0000
changeset 505141 04f0bbf40bf36957dc1f72a8aae9916df0e3222f
parent 407203 94f5cca9efbafee99ca4fb832b4aef6144ac469d
child 505383 6f3709b3878117466168c40affa7bca0b60cf75b
permissions -rw-r--r--
Bug 1508472 - Part 5: Fifth batch of comment fix-ups in preparation for the tree reformat r=sylvestre This is a best effort attempt at ensuring that the adverse impact of reformatting the entire tree over the comments would be minimal. I've used a combination of strategies including disabling of formatting, some manual formatting and some changes to formatting to work around some clang-format limitations. Differential Revision: https://phabricator.services.mozilla.com/D13371

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2; -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "PerfMeasurement.h"
#include "jsperf.h"
#include "mozilla/ModuleUtils.h"
#include "nsMemory.h"
#include "mozilla/Preferences.h"
#include "mozJSComponentLoader.h"
#include "nsZipArchive.h"
#include "xpc_make_class.h"

#define JSPERF_CONTRACTID \
  "@mozilla.org/jsperf;1"

#define JSPERF_CID            \
{ 0x421c38e6, 0xaee0, 0x4509, \
  { 0xa0, 0x25, 0x13, 0x0f, 0x43, 0x78, 0x03, 0x5a } }

namespace mozilla {
namespace jsperf {

NS_GENERIC_FACTORY_CONSTRUCTOR(Module)

NS_IMPL_ISUPPORTS(Module, nsIXPCScriptable)

Module::Module() = default;

Module::~Module() = default;

#define XPC_MAP_CLASSNAME Module
#define XPC_MAP_QUOTED_CLASSNAME "Module"
#define XPC_MAP_FLAGS XPC_SCRIPTABLE_WANT_CALL
#include "xpc_map_end.h"

static bool
SealObjectAndPrototype(JSContext* cx, JS::Handle<JSObject *> parent, const char* name)
{
  JS::Rooted<JS::Value> prop(cx);
  if (!JS_GetProperty(cx, parent, name, &prop))
    return false;

  if (prop.isUndefined()) {
    // Pretend we sealed the object.
    return true;
  }

  JS::Rooted<JSObject*> obj(cx, prop.toObjectOrNull());
  if (!JS_GetProperty(cx, obj, "prototype", &prop))
    return false;

  JS::Rooted<JSObject*> prototype(cx, prop.toObjectOrNull());
  return JS_FreezeObject(cx, obj) && JS_FreezeObject(cx, prototype);
}

static bool
InitAndSealPerfMeasurementClass(JSContext* cx, JS::Handle<JSObject*> global)
{
  // Init the PerfMeasurement class
  if (!JS::RegisterPerfMeasurement(cx, global))
    return false;

  // Seal up Object, Function, and Array and their prototypes.  (This single
  // object instance is shared amongst everyone who imports the jsperf module.)
  if (!SealObjectAndPrototype(cx, global, "Object") ||
      !SealObjectAndPrototype(cx, global, "Function") ||
      !SealObjectAndPrototype(cx, global, "Array"))
    return false;

  // Finally, seal the global object, for good measure. (But not recursively;
  // this breaks things.)
  return JS_FreezeObject(cx, global);
}

NS_IMETHODIMP
Module::Call(nsIXPConnectWrappedNative* wrapper,
             JSContext* cx,
             JSObject* obj,
             const JS::CallArgs& args,
             bool* _retval)
{

  mozJSComponentLoader* loader = mozJSComponentLoader::Get();
  JS::Rooted<JSObject*> targetObj(cx);
  loader->FindTargetObject(cx, &targetObj);

  *_retval = InitAndSealPerfMeasurementClass(cx, targetObj);
  return NS_OK;
}

} // namespace jsperf
} // namespace mozilla

NS_DEFINE_NAMED_CID(JSPERF_CID);

static const mozilla::Module::CIDEntry kPerfCIDs[] = {
  { &kJSPERF_CID, false, nullptr, mozilla::jsperf::ModuleConstructor },
  { nullptr }
};

static const mozilla::Module::ContractIDEntry kPerfContracts[] = {
  { JSPERF_CONTRACTID, &kJSPERF_CID },
  { nullptr }
};

static const mozilla::Module kPerfModule = {
  mozilla::Module::kVersion,
  kPerfCIDs,
  kPerfContracts
};

NSMODULE_DEFN(jsperf) = &kPerfModule;