gecko-dev/devtools/server/nsJSInspector.cpp

/* -*-  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 "nsJSInspector.h"
#include "nsIXPConnect.h"
#include "nsThreadUtils.h"
#include "jsfriendapi.h"
#include "mozilla/HoldDropJSObjects.h"
#include "mozilla/ModuleUtils.h"
#include "mozilla/dom/ScriptSettings.h"
#include "nsServiceManagerUtils.h"
#include "nsMemory.h"
#include "nsArray.h"
#include "nsTArray.h"

#define JSINSPECTOR_CONTRACTID \
  "@mozilla.org/jsinspector;1"

#define JSINSPECTOR_CID \
{ 0xec5aa99c, 0x7abb, 0x4142, { 0xac, 0x5f, 0xaa, 0xb2, 0x41, 0x9e, 0x38, 0xe2 } }

namespace mozilla {
namespace jsinspector {

NS_GENERIC_FACTORY_CONSTRUCTOR(nsJSInspector)

NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(nsJSInspector)
  NS_INTERFACE_MAP_ENTRY(nsISupports)
  NS_INTERFACE_MAP_ENTRY(nsIJSInspector)
NS_INTERFACE_MAP_END

NS_IMPL_CYCLE_COLLECTION_CLASS(nsJSInspector)

NS_IMPL_CYCLE_COLLECTING_ADDREF(nsJSInspector)
NS_IMPL_CYCLE_COLLECTING_RELEASE(nsJSInspector)

NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(nsJSInspector)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE_SCRIPT_OBJECTS
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END

NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(nsJSInspector)
  tmp->mRequestors.Clear();
  tmp->mLastRequestor = JS::NullValue();
NS_IMPL_CYCLE_COLLECTION_UNLINK_END

NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(nsJSInspector)
  for (uint32_t i = 0; i < tmp->mRequestors.Length(); ++i) {
    NS_IMPL_CYCLE_COLLECTION_TRACE_JSVAL_MEMBER_CALLBACK(mRequestors[i])
  }
  NS_IMPL_CYCLE_COLLECTION_TRACE_JSVAL_MEMBER_CALLBACK(mLastRequestor)
NS_IMPL_CYCLE_COLLECTION_TRACE_END

nsJSInspector::nsJSInspector() : mNestedLoopLevel(0), mRequestors(1), mLastRequestor(JS::NullValue())
{
}

nsJSInspector::~nsJSInspector()
{
  MOZ_ASSERT(mRequestors.Length() == 0);
  MOZ_ASSERT(mLastRequestor.isNull());
  mozilla::DropJSObjects(this);
}

NS_IMETHODIMP
nsJSInspector::EnterNestedEventLoop(JS::Handle<JS::Value> requestor, uint32_t *out)
{
  nsresult rv = NS_OK;

  mLastRequestor = requestor;
  mRequestors.AppendElement(requestor);
  mozilla::HoldJSObjects(this);

  mozilla::dom::AutoNoJSAPI nojsapi;

  uint32_t nestLevel = ++mNestedLoopLevel;
  while (NS_SUCCEEDED(rv) && mNestedLoopLevel >= nestLevel) {
    if (!NS_ProcessNextEvent())
      rv = NS_ERROR_UNEXPECTED;
  }

  NS_ASSERTION(mNestedLoopLevel <= nestLevel,
               "nested event didn't unwind properly");

  if (mNestedLoopLevel == nestLevel) {
    mLastRequestor = mRequestors.ElementAt(--mNestedLoopLevel);
  }

  *out = mNestedLoopLevel;
  return rv;
}

NS_IMETHODIMP
nsJSInspector::ExitNestedEventLoop(uint32_t *out)
{
  if (mNestedLoopLevel > 0) {
    mRequestors.RemoveElementAt(--mNestedLoopLevel);
    if (mNestedLoopLevel > 0)
      mLastRequestor = mRequestors.ElementAt(mNestedLoopLevel - 1);
    else
      mLastRequestor = JS::NullValue();
  } else {
    return NS_ERROR_FAILURE;
  }

  *out = mNestedLoopLevel;

  return NS_OK;
}

NS_IMETHODIMP
nsJSInspector::GetEventLoopNestLevel(uint32_t *out)
{
  *out = mNestedLoopLevel;
  return NS_OK;
}

NS_IMETHODIMP
nsJSInspector::GetLastNestRequestor(JS::MutableHandle<JS::Value> out)
{
  out.set(mLastRequestor);
  return NS_OK;
}

} // namespace jsinspector
} // namespace mozilla

NS_DEFINE_NAMED_CID(JSINSPECTOR_CID);

static const mozilla::Module::CIDEntry kJSInspectorCIDs[] = {
  { &kJSINSPECTOR_CID, false, nullptr, mozilla::jsinspector::nsJSInspectorConstructor },
  { nullptr }
};

static const mozilla::Module::ContractIDEntry kJSInspectorContracts[] = {
  { JSINSPECTOR_CONTRACTID, &kJSINSPECTOR_CID },
  { nullptr }
};

static const mozilla::Module kJSInspectorModule = {
  mozilla::Module::kVersion,
  kJSInspectorCIDs,
  kJSInspectorContracts
};

NSMODULE_DEFN(jsinspector) = &kJSInspectorModule;