gecko-dev/dom/indexedDB/IDBCursor.cpp

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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 "IDBCursor.h"

#include "IDBDatabase.h"
#include "IDBIndex.h"
#include "IDBObjectStore.h"
#include "IDBRequest.h"
#include "IDBTransaction.h"
#include "IndexedDatabaseInlines.h"
#include "mozilla/ErrorResult.h"
#include "mozilla/dom/UnionTypes.h"
#include "mozilla/dom/indexedDB/PBackgroundIDBSharedTypes.h"
#include "nsString.h"
#include "ProfilerHelpers.h"
#include "ReportInternalError.h"

// Include this last to avoid path problems on Windows.
#include "ActorsChild.h"

namespace mozilla {
namespace dom {

using namespace indexedDB;

IDBCursor::IDBCursor(Type aType, BackgroundCursorChild* aBackgroundActor,
                     Key aKey)
    : mBackgroundActor(aBackgroundActor),
      mRequest(aBackgroundActor->GetRequest()),
      mSourceObjectStore(aBackgroundActor->GetObjectStore()),
      mSourceIndex(aBackgroundActor->GetIndex()),
      mTransaction(mRequest->GetTransaction()),
      mCachedKey(JS::UndefinedValue()),
      mCachedPrimaryKey(JS::UndefinedValue()),
      mCachedValue(JS::UndefinedValue()),
      mKey(std::move(aKey)),
      mType(aType),
      mDirection(aBackgroundActor->GetDirection()),
      mHaveCachedKey(false),
      mHaveCachedPrimaryKey(false),
      mHaveCachedValue(false),
      mRooted(false),
      mContinueCalled(false),
      mHaveValue(true) {
  MOZ_ASSERT(aBackgroundActor);
  aBackgroundActor->AssertIsOnOwningThread();
  MOZ_ASSERT(mRequest);
  MOZ_ASSERT_IF(aType == Type::ObjectStore || aType == Type::ObjectStoreKey,
                mSourceObjectStore);
  MOZ_ASSERT_IF(aType == Type::Index || aType == Type::IndexKey, mSourceIndex);
  MOZ_ASSERT(mTransaction);
  MOZ_ASSERT(!aKey.IsUnset());

  mTransaction->RegisterCursor(this);
}

bool IDBCursor::IsLocaleAware() const {
  return mSourceIndex && !mSourceIndex->Locale().IsEmpty();
}

IDBCursor::~IDBCursor() {
  AssertIsOnOwningThread();

  mTransaction->UnregisterCursor(this);

  DropJSObjects();

  if (mBackgroundActor) {
    mBackgroundActor->SendDeleteMeInternal();
    MOZ_ASSERT(!mBackgroundActor, "SendDeleteMeInternal should have cleared!");
  }
}

// static
RefPtr<IDBCursor> IDBCursor::Create(BackgroundCursorChild* aBackgroundActor,
                                    Key aKey,
                                    StructuredCloneReadInfo&& aCloneInfo) {
  MOZ_ASSERT(aBackgroundActor);
  aBackgroundActor->AssertIsOnOwningThread();
  MOZ_ASSERT(aBackgroundActor->GetObjectStore());
  MOZ_ASSERT(!aBackgroundActor->GetIndex());
  MOZ_ASSERT(!aKey.IsUnset());

  RefPtr<IDBCursor> cursor =
      new IDBCursor(Type::ObjectStore, aBackgroundActor, std::move(aKey));

  cursor->mCloneInfo = std::move(aCloneInfo);

  return cursor;
}

// static
RefPtr<IDBCursor> IDBCursor::Create(BackgroundCursorChild* aBackgroundActor,
                                    Key aKey) {
  MOZ_ASSERT(aBackgroundActor);
  aBackgroundActor->AssertIsOnOwningThread();
  MOZ_ASSERT(aBackgroundActor->GetObjectStore());
  MOZ_ASSERT(!aBackgroundActor->GetIndex());
  MOZ_ASSERT(!aKey.IsUnset());

  RefPtr<IDBCursor> cursor =
      new IDBCursor(Type::ObjectStoreKey, aBackgroundActor, std::move(aKey));

  return cursor;
}

// static
RefPtr<IDBCursor> IDBCursor::Create(BackgroundCursorChild* aBackgroundActor,
                                    Key aKey, Key aSortKey, Key aPrimaryKey,
                                    StructuredCloneReadInfo&& aCloneInfo) {
  MOZ_ASSERT(aBackgroundActor);
  aBackgroundActor->AssertIsOnOwningThread();
  MOZ_ASSERT(aBackgroundActor->GetIndex());
  MOZ_ASSERT(!aBackgroundActor->GetObjectStore());
  MOZ_ASSERT(!aKey.IsUnset());
  MOZ_ASSERT(!aPrimaryKey.IsUnset());

  RefPtr<IDBCursor> cursor =
      new IDBCursor(Type::Index, aBackgroundActor, std::move(aKey));

  cursor->mSortKey = std::move(aSortKey);
  cursor->mPrimaryKey = std::move(aPrimaryKey);
  cursor->mCloneInfo = std::move(aCloneInfo);

  return cursor;
}

// static
RefPtr<IDBCursor> IDBCursor::Create(BackgroundCursorChild* aBackgroundActor,
                                    Key aKey, Key aSortKey, Key aPrimaryKey) {
  MOZ_ASSERT(aBackgroundActor);
  aBackgroundActor->AssertIsOnOwningThread();
  MOZ_ASSERT(aBackgroundActor->GetIndex());
  MOZ_ASSERT(!aBackgroundActor->GetObjectStore());
  MOZ_ASSERT(!aKey.IsUnset());
  MOZ_ASSERT(!aPrimaryKey.IsUnset());

  RefPtr<IDBCursor> cursor =
      new IDBCursor(Type::IndexKey, aBackgroundActor, std::move(aKey));

  cursor->mSortKey = std::move(aSortKey);
  cursor->mPrimaryKey = std::move(aPrimaryKey);

  return cursor;
}

// static
auto IDBCursor::ConvertDirection(IDBCursorDirection aDirection) -> Direction {
  switch (aDirection) {
    case mozilla::dom::IDBCursorDirection::Next:
      return Direction::Next;

    case mozilla::dom::IDBCursorDirection::Nextunique:
      return Direction::NextUnique;

    case mozilla::dom::IDBCursorDirection::Prev:
      return Direction::Prev;

    case mozilla::dom::IDBCursorDirection::Prevunique:
      return Direction::PrevUnique;

    default:
      MOZ_CRASH("Unknown direction!");
  }
}

#ifdef DEBUG

void IDBCursor::AssertIsOnOwningThread() const {
  MOZ_ASSERT(mTransaction);
  mTransaction->AssertIsOnOwningThread();
}

#endif  // DEBUG

void IDBCursor::DropJSObjects() {
  AssertIsOnOwningThread();

  Reset();

  if (!mRooted) {
    return;
  }

  mRooted = false;

  mozilla::DropJSObjects(this);
}

bool IDBCursor::IsSourceDeleted() const {
  AssertIsOnOwningThread();
  MOZ_ASSERT(mTransaction);
  MOZ_ASSERT(mTransaction->CanAcceptRequests());

  IDBObjectStore* sourceObjectStore;
  if (mType == Type::Index || mType == Type::IndexKey) {
    MOZ_ASSERT(mSourceIndex);

    if (mSourceIndex->IsDeleted()) {
      return true;
    }

    sourceObjectStore = mSourceIndex->ObjectStore();
    MOZ_ASSERT(sourceObjectStore);
  } else {
    MOZ_ASSERT(mSourceObjectStore);
    sourceObjectStore = mSourceObjectStore;
  }

  return sourceObjectStore->IsDeleted();
}

void IDBCursor::Reset() {
  AssertIsOnOwningThread();

  mCachedKey.setUndefined();
  mCachedPrimaryKey.setUndefined();
  mCachedValue.setUndefined();
  IDBObjectStore::ClearCloneReadInfo(mCloneInfo);

  mHaveCachedKey = false;
  mHaveCachedPrimaryKey = false;
  mHaveCachedValue = false;
  mHaveValue = false;
  mContinueCalled = false;
}

nsIGlobalObject* IDBCursor::GetParentObject() const {
  AssertIsOnOwningThread();
  MOZ_ASSERT(mTransaction);

  return mTransaction->GetParentObject();
}

IDBCursorDirection IDBCursor::GetDirection() const {
  AssertIsOnOwningThread();

  switch (mDirection) {
    case Direction::Next:
      return IDBCursorDirection::Next;

    case Direction::NextUnique:
      return IDBCursorDirection::Nextunique;

    case Direction::Prev:
      return IDBCursorDirection::Prev;

    case Direction::PrevUnique:
      return IDBCursorDirection::Prevunique;

    default:
      MOZ_CRASH("Bad direction!");
  }
}

IDBCursor::Type IDBCursor::GetType() const { return mType; }

void IDBCursor::GetSource(OwningIDBObjectStoreOrIDBIndex& aSource) const {
  AssertIsOnOwningThread();

  switch (mType) {
    case Type::ObjectStore:
    case Type::ObjectStoreKey:
      MOZ_ASSERT(mSourceObjectStore);
      aSource.SetAsIDBObjectStore() = mSourceObjectStore;
      return;

    case Type::Index:
    case Type::IndexKey:
      MOZ_ASSERT(mSourceIndex);
      aSource.SetAsIDBIndex() = mSourceIndex;
      return;

    default:
      MOZ_ASSERT_UNREACHABLE("Bad type!");
  }
}

void IDBCursor::GetKey(JSContext* aCx, JS::MutableHandle<JS::Value> aResult,
                       ErrorResult& aRv) {
  AssertIsOnOwningThread();
  MOZ_ASSERT(!mKey.IsUnset() || !mHaveValue);

  if (!mHaveValue) {
    aResult.setUndefined();
    return;
  }

  if (!mHaveCachedKey) {
    if (!mRooted) {
      mozilla::HoldJSObjects(this);
      mRooted = true;
    }

    aRv = mKey.ToJSVal(aCx, mCachedKey);
    if (NS_WARN_IF(aRv.Failed())) {
      return;
    }

    mHaveCachedKey = true;
  }

  aResult.set(mCachedKey);
}

void IDBCursor::GetPrimaryKey(JSContext* aCx,
                              JS::MutableHandle<JS::Value> aResult,
                              ErrorResult& aRv) {
  AssertIsOnOwningThread();

  if (!mHaveValue) {
    aResult.setUndefined();
    return;
  }

  if (!mHaveCachedPrimaryKey) {
    if (!mRooted) {
      mozilla::HoldJSObjects(this);
      mRooted = true;
    }

    const Key& key =
        (mType == Type::ObjectStore || mType == Type::ObjectStoreKey)
            ? mKey
            : mPrimaryKey;

    MOZ_ASSERT(!key.IsUnset());

    aRv = key.ToJSVal(aCx, mCachedPrimaryKey);
    if (NS_WARN_IF(aRv.Failed())) {
      return;
    }

    mHaveCachedPrimaryKey = true;
  }

  aResult.set(mCachedPrimaryKey);
}

void IDBCursor::GetValue(JSContext* aCx, JS::MutableHandle<JS::Value> aResult,
                         ErrorResult& aRv) {
  AssertIsOnOwningThread();
  MOZ_ASSERT(mType == Type::ObjectStore || mType == Type::Index);

  if (!mHaveValue) {
    aResult.setUndefined();
    return;
  }

  if (!mHaveCachedValue) {
    if (!mRooted) {
      mozilla::HoldJSObjects(this);
      mRooted = true;
    }

    JS::Rooted<JS::Value> val(aCx);
    if (NS_WARN_IF(!IDBObjectStore::DeserializeValue(aCx, mCloneInfo, &val))) {
      aRv.Throw(NS_ERROR_DOM_DATA_CLONE_ERR);
      return;
    }

    IDBObjectStore::ClearCloneReadInfo(mCloneInfo);

    mCachedValue = val;
    mHaveCachedValue = true;
  }

  aResult.set(mCachedValue);
}

void IDBCursor::Continue(JSContext* aCx, JS::Handle<JS::Value> aKey,
                         ErrorResult& aRv) {
  AssertIsOnOwningThread();

  if (!mTransaction->CanAcceptRequests()) {
    aRv.Throw(NS_ERROR_DOM_INDEXEDDB_TRANSACTION_INACTIVE_ERR);
    return;
  }

  if (IsSourceDeleted() || !mHaveValue || mContinueCalled) {
    aRv.Throw(NS_ERROR_DOM_INDEXEDDB_NOT_ALLOWED_ERR);
    return;
  }

  Key key;
  auto result = key.SetFromJSVal(aCx, aKey, aRv);
  if (!result.Is(Ok, aRv)) {
    if (result.Is(Invalid, aRv)) {
      aRv.Throw(NS_ERROR_DOM_INDEXEDDB_DATA_ERR);
    }
    return;
  }

  if (IsLocaleAware() && !key.IsUnset()) {
    Key tmp;
    result = key.ToLocaleAwareKey(tmp, mSourceIndex->Locale(), aRv);
    if (!result.Is(Ok, aRv)) {
      if (result.Is(Invalid, aRv)) {
        aRv.Throw(NS_ERROR_DOM_INDEXEDDB_DATA_ERR);
      }
      return;
    }
    key = tmp;
  }

  const Key& sortKey = IsLocaleAware() ? mSortKey : mKey;

  if (!key.IsUnset()) {
    switch (mDirection) {
      case Direction::Next:
      case Direction::NextUnique:
        if (key <= sortKey) {
          aRv.Throw(NS_ERROR_DOM_INDEXEDDB_DATA_ERR);
          return;
        }
        break;

      case Direction::Prev:
      case Direction::PrevUnique:
        if (key >= sortKey) {
          aRv.Throw(NS_ERROR_DOM_INDEXEDDB_DATA_ERR);
          return;
        }
        break;

      default:
        MOZ_CRASH("Unknown direction type!");
    }
  }

  const uint64_t requestSerialNumber = IDBRequest::NextSerialNumber();
  mRequest->SetLoggingSerialNumber(requestSerialNumber);

  if (mType == Type::ObjectStore || mType == Type::ObjectStoreKey) {
    IDB_LOG_MARK_CHILD_TRANSACTION_REQUEST(
        "database(%s).transaction(%s).objectStore(%s)."
        "cursor(%s).continue(%s)",
        "IDBCursor.continue()", mTransaction->LoggingSerialNumber(),
        requestSerialNumber, IDB_LOG_STRINGIFY(mTransaction->Database()),
        IDB_LOG_STRINGIFY(mTransaction), IDB_LOG_STRINGIFY(mSourceObjectStore),
        IDB_LOG_STRINGIFY(mDirection), IDB_LOG_STRINGIFY(key));
  } else {
    IDB_LOG_MARK_CHILD_TRANSACTION_REQUEST(
        "database(%s).transaction(%s).objectStore(%s)."
        "index(%s).cursor(%s).continue(%s)",
        "IDBCursor.continue()", mTransaction->LoggingSerialNumber(),
        requestSerialNumber, IDB_LOG_STRINGIFY(mTransaction->Database()),
        IDB_LOG_STRINGIFY(mTransaction),
        IDB_LOG_STRINGIFY(mSourceIndex->ObjectStore()),
        IDB_LOG_STRINGIFY(mSourceIndex), IDB_LOG_STRINGIFY(mDirection),
        IDB_LOG_STRINGIFY(key));
  }

  mBackgroundActor->SendContinueInternal(ContinueParams(key), mKey,
                                         mPrimaryKey);

  mContinueCalled = true;
}

void IDBCursor::ContinuePrimaryKey(JSContext* aCx, JS::Handle<JS::Value> aKey,
                                   JS::Handle<JS::Value> aPrimaryKey,
                                   ErrorResult& aRv) {
  AssertIsOnOwningThread();

  if (!mTransaction->CanAcceptRequests()) {
    aRv.Throw(NS_ERROR_DOM_INDEXEDDB_TRANSACTION_INACTIVE_ERR);
    return;
  }

  if (IsSourceDeleted()) {
    aRv.Throw(NS_ERROR_DOM_INDEXEDDB_NOT_ALLOWED_ERR);
    return;
  }

  if ((mType != Type::Index && mType != Type::IndexKey) ||
      (mDirection != Direction::Next && mDirection != Direction::Prev)) {
    aRv.Throw(NS_ERROR_DOM_INVALID_ACCESS_ERR);
    return;
  }

  if (!mHaveValue || mContinueCalled) {
    aRv.Throw(NS_ERROR_DOM_INDEXEDDB_NOT_ALLOWED_ERR);
    return;
  }

  Key key;
  auto result = key.SetFromJSVal(aCx, aKey, aRv);
  if (!result.Is(Ok, aRv)) {
    if (result.Is(Invalid, aRv)) {
      aRv.Throw(NS_ERROR_DOM_INDEXEDDB_DATA_ERR);
    }
    return;
  }

  if (IsLocaleAware() && !key.IsUnset()) {
    Key tmp;
    result = key.ToLocaleAwareKey(tmp, mSourceIndex->Locale(), aRv);
    if (!result.Is(Ok, aRv)) {
      if (result.Is(Invalid, aRv)) {
        aRv.Throw(NS_ERROR_DOM_INDEXEDDB_DATA_ERR);
      }
      return;
    }
    key = tmp;
  }

  if (key.IsUnset()) {
    aRv.Throw(NS_ERROR_DOM_INDEXEDDB_DATA_ERR);
    return;
  }

  Key primaryKey;
  result = primaryKey.SetFromJSVal(aCx, aPrimaryKey, aRv);
  if (!result.Is(Ok, aRv)) {
    if (result.Is(Invalid, aRv)) {
      aRv.Throw(NS_ERROR_DOM_INDEXEDDB_DATA_ERR);
    }
    return;
  }

  if (primaryKey.IsUnset()) {
    aRv.Throw(NS_ERROR_DOM_INDEXEDDB_DATA_ERR);
    return;
  }

  const Key& sortKey = IsLocaleAware() ? mSortKey : mKey;

  switch (mDirection) {
    case Direction::Next:
      if (key < sortKey || (key == sortKey && primaryKey <= mPrimaryKey)) {
        aRv.Throw(NS_ERROR_DOM_INDEXEDDB_DATA_ERR);
        return;
      }
      break;

    case Direction::Prev:
      if (key > sortKey || (key == sortKey && primaryKey >= mPrimaryKey)) {
        aRv.Throw(NS_ERROR_DOM_INDEXEDDB_DATA_ERR);
        return;
      }
      break;

    default:
      MOZ_CRASH("Unknown direction type!");
  }

  const uint64_t requestSerialNumber = IDBRequest::NextSerialNumber();
  mRequest->SetLoggingSerialNumber(requestSerialNumber);

  IDB_LOG_MARK_CHILD_TRANSACTION_REQUEST(
      "database(%s).transaction(%s).objectStore(%s)."
      "index(%s).cursor(%s).continuePrimaryKey(%s, %s)",
      "IDBCursor.continuePrimaryKey()", mTransaction->LoggingSerialNumber(),
      requestSerialNumber, IDB_LOG_STRINGIFY(mTransaction->Database()),
      IDB_LOG_STRINGIFY(mTransaction),
      IDB_LOG_STRINGIFY(mSourceIndex->ObjectStore()),
      IDB_LOG_STRINGIFY(mSourceIndex), IDB_LOG_STRINGIFY(mDirection),
      IDB_LOG_STRINGIFY(key), IDB_LOG_STRINGIFY(primaryKey));

  mBackgroundActor->SendContinueInternal(
      ContinuePrimaryKeyParams(key, primaryKey), mKey, mPrimaryKey);

  mContinueCalled = true;
}

void IDBCursor::Advance(uint32_t aCount, ErrorResult& aRv) {
  AssertIsOnOwningThread();

  if (!aCount) {
    aRv.ThrowTypeError(u"0 (Zero) is not a valid advance count.");
    return;
  }

  if (!mTransaction->CanAcceptRequests()) {
    aRv.Throw(NS_ERROR_DOM_INDEXEDDB_TRANSACTION_INACTIVE_ERR);
    return;
  }

  if (IsSourceDeleted() || !mHaveValue || mContinueCalled) {
    aRv.Throw(NS_ERROR_DOM_INDEXEDDB_NOT_ALLOWED_ERR);
    return;
  }

  const uint64_t requestSerialNumber = IDBRequest::NextSerialNumber();
  mRequest->SetLoggingSerialNumber(requestSerialNumber);

  if (mType == Type::ObjectStore || mType == Type::ObjectStoreKey) {
    IDB_LOG_MARK_CHILD_TRANSACTION_REQUEST(
        "database(%s).transaction(%s).objectStore(%s)."
        "cursor(%s).advance(%ld)",
        "IDBCursor.advance()", mTransaction->LoggingSerialNumber(),
        requestSerialNumber, IDB_LOG_STRINGIFY(mTransaction->Database()),
        IDB_LOG_STRINGIFY(mTransaction), IDB_LOG_STRINGIFY(mSourceObjectStore),
        IDB_LOG_STRINGIFY(mDirection), aCount);
  } else {
    IDB_LOG_MARK_CHILD_TRANSACTION_REQUEST(
        "database(%s).transaction(%s).objectStore(%s)."
        "index(%s).cursor(%s).advance(%ld)",
        "IDBCursor.advance()", mTransaction->LoggingSerialNumber(),
        requestSerialNumber, IDB_LOG_STRINGIFY(mTransaction->Database()),
        IDB_LOG_STRINGIFY(mTransaction),
        IDB_LOG_STRINGIFY(mSourceIndex->ObjectStore()),
        IDB_LOG_STRINGIFY(mSourceIndex), IDB_LOG_STRINGIFY(mDirection), aCount);
  }

  mBackgroundActor->SendContinueInternal(AdvanceParams(aCount), mKey,
                                         mPrimaryKey);

  mContinueCalled = true;
}

RefPtr<IDBRequest> IDBCursor::Update(JSContext* aCx,
                                     JS::Handle<JS::Value> aValue,
                                     ErrorResult& aRv) {
  AssertIsOnOwningThread();

  if (!mTransaction->CanAcceptRequests()) {
    aRv.Throw(NS_ERROR_DOM_INDEXEDDB_TRANSACTION_INACTIVE_ERR);
    return nullptr;
  }

  if (!mTransaction->IsWriteAllowed()) {
    aRv.Throw(NS_ERROR_DOM_INDEXEDDB_READ_ONLY_ERR);
    return nullptr;
  }

  if (mTransaction->GetMode() == IDBTransaction::Mode::Cleanup ||
      IsSourceDeleted() || !mHaveValue || mType == Type::ObjectStoreKey ||
      mType == Type::IndexKey || mContinueCalled) {
    aRv.Throw(NS_ERROR_DOM_INDEXEDDB_NOT_ALLOWED_ERR);
    return nullptr;
  }

  MOZ_ASSERT(mType == Type::ObjectStore || mType == Type::Index);
  MOZ_ASSERT(!mKey.IsUnset());
  MOZ_ASSERT_IF(mType == Type::Index, !mPrimaryKey.IsUnset());

  mTransaction->InvalidateCursorCaches();

  IDBObjectStore* objectStore;
  if (mType == Type::ObjectStore) {
    objectStore = mSourceObjectStore;
  } else {
    objectStore = mSourceIndex->ObjectStore();
  }

  MOZ_ASSERT(objectStore);

  IDBObjectStore::ValueWrapper valueWrapper(aCx, aValue);

  const Key& primaryKey = (mType == Type::ObjectStore) ? mKey : mPrimaryKey;

  RefPtr<IDBRequest> request;

  if (objectStore->HasValidKeyPath()) {
    if (!valueWrapper.Clone(aCx)) {
      aRv.Throw(NS_ERROR_DOM_DATA_CLONE_ERR);
      return nullptr;
    }

    // Make sure the object given has the correct keyPath value set on it.
    const KeyPath& keyPath = objectStore->GetKeyPath();
    Key key;

    aRv = keyPath.ExtractKey(aCx, valueWrapper.Value(), key);
    if (aRv.Failed()) {
      return nullptr;
    }

    if (key != primaryKey) {
      aRv.Throw(NS_ERROR_DOM_INDEXEDDB_DATA_ERR);
      return nullptr;
    }

    request = objectStore->AddOrPut(aCx, valueWrapper,
                                    /* aKey */ JS::UndefinedHandleValue,
                                    /* aOverwrite */ true,
                                    /* aFromCursor */ true, aRv);
    if (aRv.Failed()) {
      return nullptr;
    }
  } else {
    JS::Rooted<JS::Value> keyVal(aCx);
    aRv = primaryKey.ToJSVal(aCx, &keyVal);
    if (aRv.Failed()) {
      return nullptr;
    }

    request = objectStore->AddOrPut(aCx, valueWrapper, keyVal,
                                    /* aOverwrite */ true,
                                    /* aFromCursor */ true, aRv);
    if (aRv.Failed()) {
      return nullptr;
    }
  }

  request->SetSource(this);

  if (mType == Type::ObjectStore) {
    IDB_LOG_MARK_CHILD_TRANSACTION_REQUEST(
        "database(%s).transaction(%s).objectStore(%s)."
        "cursor(%s).update(%s)",
        "IDBCursor.update()", mTransaction->LoggingSerialNumber(),
        request->LoggingSerialNumber(),
        IDB_LOG_STRINGIFY(mTransaction->Database()),
        IDB_LOG_STRINGIFY(mTransaction), IDB_LOG_STRINGIFY(objectStore),
        IDB_LOG_STRINGIFY(mDirection),
        IDB_LOG_STRINGIFY(objectStore, primaryKey));
  } else {
    IDB_LOG_MARK_CHILD_TRANSACTION_REQUEST(
        "database(%s).transaction(%s).objectStore(%s)."
        "index(%s).cursor(%s).update(%s)",
        "IDBCursor.update()", mTransaction->LoggingSerialNumber(),
        request->LoggingSerialNumber(),
        IDB_LOG_STRINGIFY(mTransaction->Database()),
        IDB_LOG_STRINGIFY(mTransaction), IDB_LOG_STRINGIFY(objectStore),
        IDB_LOG_STRINGIFY(mSourceIndex), IDB_LOG_STRINGIFY(mDirection),
        IDB_LOG_STRINGIFY(objectStore, primaryKey));
  }

  return request;
}

RefPtr<IDBRequest> IDBCursor::Delete(JSContext* aCx, ErrorResult& aRv) {
  AssertIsOnOwningThread();

  if (!mTransaction->CanAcceptRequests()) {
    aRv.Throw(NS_ERROR_DOM_INDEXEDDB_TRANSACTION_INACTIVE_ERR);
    return nullptr;
  }

  if (!mTransaction->IsWriteAllowed()) {
    aRv.Throw(NS_ERROR_DOM_INDEXEDDB_READ_ONLY_ERR);
    return nullptr;
  }

  if (IsSourceDeleted() || !mHaveValue || mType == Type::ObjectStoreKey ||
      mType == Type::IndexKey || mContinueCalled) {
    aRv.Throw(NS_ERROR_DOM_INDEXEDDB_NOT_ALLOWED_ERR);
    return nullptr;
  }

  MOZ_ASSERT(mType == Type::ObjectStore || mType == Type::Index);
  MOZ_ASSERT(!mKey.IsUnset());

  mTransaction->InvalidateCursorCaches();

  IDBObjectStore* const objectStore = mType == Type::ObjectStore
                                          ? mSourceObjectStore.get()
                                          : mSourceIndex->ObjectStore();

  MOZ_ASSERT(objectStore);

  const Key& primaryKey = (mType == Type::ObjectStore) ? mKey : mPrimaryKey;

  JS::Rooted<JS::Value> key(aCx);
  aRv = primaryKey.ToJSVal(aCx, &key);
  if (NS_WARN_IF(aRv.Failed())) {
    return nullptr;
  }

  RefPtr<IDBRequest> request =
      objectStore->DeleteInternal(aCx, key, /* aFromCursor */ true, aRv);
  if (aRv.Failed()) {
    return nullptr;
  }

  request->SetSource(this);

  if (mType == Type::ObjectStore) {
    IDB_LOG_MARK_CHILD_TRANSACTION_REQUEST(
        "database(%s).transaction(%s).objectStore(%s)."
        "cursor(%s).delete(%s)",
        "IDBCursor.delete()", mTransaction->LoggingSerialNumber(),
        request->LoggingSerialNumber(),
        IDB_LOG_STRINGIFY(mTransaction->Database()),
        IDB_LOG_STRINGIFY(mTransaction), IDB_LOG_STRINGIFY(objectStore),
        IDB_LOG_STRINGIFY(mDirection),
        IDB_LOG_STRINGIFY(objectStore, primaryKey));
  } else {
    IDB_LOG_MARK_CHILD_TRANSACTION_REQUEST(
        "database(%s).transaction(%s).objectStore(%s)."
        "index(%s).cursor(%s).delete(%s)",
        "IDBCursor.delete()", mTransaction->LoggingSerialNumber(),
        request->LoggingSerialNumber(),
        IDB_LOG_STRINGIFY(mTransaction->Database()),
        IDB_LOG_STRINGIFY(mTransaction), IDB_LOG_STRINGIFY(objectStore),
        IDB_LOG_STRINGIFY(mSourceIndex), IDB_LOG_STRINGIFY(mDirection),
        IDB_LOG_STRINGIFY(objectStore, primaryKey));
  }

  return request;
}

void IDBCursor::Reset(Key&& aKey, StructuredCloneReadInfo&& aValue) {
  AssertIsOnOwningThread();
  MOZ_ASSERT(mType == Type::ObjectStore);

  Reset();

  mKey = std::move(aKey);
  mCloneInfo = std::move(aValue);

  mHaveValue = !mKey.IsUnset();
}

void IDBCursor::Reset(Key&& aKey) {
  AssertIsOnOwningThread();
  MOZ_ASSERT(mType == Type::ObjectStoreKey);

  Reset();

  mKey = std::move(aKey);

  mHaveValue = !mKey.IsUnset();
}

void IDBCursor::Reset(Key&& aKey, Key&& aSortKey, Key&& aPrimaryKey,
                      StructuredCloneReadInfo&& aValue) {
  AssertIsOnOwningThread();
  MOZ_ASSERT(mType == Type::Index);

  Reset();

  mKey = std::move(aKey);
  mSortKey = std::move(aSortKey);
  mPrimaryKey = std::move(aPrimaryKey);
  mCloneInfo = std::move(aValue);

  mHaveValue = !mKey.IsUnset();
}

void IDBCursor::Reset(Key&& aKey, Key&& aSortKey, Key&& aPrimaryKey) {
  AssertIsOnOwningThread();
  MOZ_ASSERT(mType == Type::IndexKey);

  Reset();

  mKey = std::move(aKey);
  mSortKey = std::move(aSortKey);
  mPrimaryKey = std::move(aPrimaryKey);

  mHaveValue = !mKey.IsUnset();
}

void IDBCursor::InvalidateCachedResponses() {
  AssertIsOnOwningThread();

  // TODO: In what case would mBackgroundActor be nullptr?
  if (mBackgroundActor) {
    mBackgroundActor->InvalidateCachedResponses();
  }
}

NS_IMPL_CYCLE_COLLECTING_ADDREF(IDBCursor)
NS_IMPL_CYCLE_COLLECTING_RELEASE(IDBCursor)

NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(IDBCursor)
  NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
  NS_INTERFACE_MAP_ENTRY(nsISupports)
NS_INTERFACE_MAP_END

NS_IMPL_CYCLE_COLLECTION_CLASS(IDBCursor)

NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(IDBCursor)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mRequest)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mSourceObjectStore)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mSourceIndex)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END

NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(IDBCursor)
  MOZ_ASSERT_IF(!tmp->mHaveCachedKey, tmp->mCachedKey.isUndefined());
  MOZ_ASSERT_IF(!tmp->mHaveCachedPrimaryKey,
                tmp->mCachedPrimaryKey.isUndefined());
  MOZ_ASSERT_IF(!tmp->mHaveCachedValue, tmp->mCachedValue.isUndefined());

  NS_IMPL_CYCLE_COLLECTION_TRACE_PRESERVED_WRAPPER
  NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mCachedKey)
  NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mCachedPrimaryKey)
  NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mCachedValue)
NS_IMPL_CYCLE_COLLECTION_TRACE_END

NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(IDBCursor)
  // Don't unlink mRequest, mSourceObjectStore, or mSourceIndex!
  NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER
  tmp->DropJSObjects();
NS_IMPL_CYCLE_COLLECTION_UNLINK_END

JSObject* IDBCursor::WrapObject(JSContext* aCx,
                                JS::Handle<JSObject*> aGivenProto) {
  AssertIsOnOwningThread();

  switch (mType) {
    case Type::ObjectStore:
    case Type::Index:
      return IDBCursorWithValue_Binding::Wrap(aCx, this, aGivenProto);

    case Type::ObjectStoreKey:
    case Type::IndexKey:
      return IDBCursor_Binding::Wrap(aCx, this, aGivenProto);

    default:
      MOZ_CRASH("Bad type!");
  }
}

}  // namespace dom
}  // namespace mozilla