/* -*- 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 "nsSVGElement.h" #include "DOMSVGPointList.h" #include "DOMSVGPoint.h" #include "nsError.h" #include "SVGAnimatedPointList.h" #include "nsCOMPtr.h" #include "nsSVGAttrTearoffTable.h" #include "nsContentUtils.h" #include "mozilla/dom/SVGPointListBinding.h" #include <algorithm> // See the comment in this file's header. // local helper functions namespace { void UpdateListIndicesFromIndex(FallibleTArray<mozilla::nsISVGPoint*>& aItemsArray, uint32_t aStartingIndex) { uint32_t length = aItemsArray.Length(); for (uint32_t i = aStartingIndex; i < length; ++i) { if (aItemsArray[i]) { aItemsArray[i]->UpdateListIndex(i); } } } } // namespace namespace mozilla { static inline nsSVGAttrTearoffTable<void, DOMSVGPointList>& SVGPointListTearoffTable() { static nsSVGAttrTearoffTable<void, DOMSVGPointList> sSVGPointListTearoffTable; return sSVGPointListTearoffTable; } NS_IMPL_CYCLE_COLLECTION_CLASS(DOMSVGPointList) NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(DOMSVGPointList) // No unlinking of mElement, we'd need to null out the value pointer (the // object it points to is held by the element) and null-check it everywhere. NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER NS_IMPL_CYCLE_COLLECTION_UNLINK_END NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(DOMSVGPointList) NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mElement) NS_IMPL_CYCLE_COLLECTION_TRAVERSE_SCRIPT_OBJECTS NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(DOMSVGPointList) NS_IMPL_CYCLE_COLLECTION_TRACE_PRESERVED_WRAPPER NS_IMPL_CYCLE_COLLECTION_TRACE_END NS_IMPL_CYCLE_COLLECTING_ADDREF(DOMSVGPointList) NS_IMPL_CYCLE_COLLECTING_RELEASE(DOMSVGPointList) NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(DOMSVGPointList) NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY NS_INTERFACE_MAP_ENTRY(nsISupports) NS_INTERFACE_MAP_END //---------------------------------------------------------------------- // Helper class: AutoChangePointListNotifier // Stack-based helper class to pair calls to WillChangePointList and // DidChangePointList. class MOZ_RAII AutoChangePointListNotifier { public: explicit AutoChangePointListNotifier(DOMSVGPointList* aPointList MOZ_GUARD_OBJECT_NOTIFIER_PARAM) : mPointList(aPointList) { MOZ_GUARD_OBJECT_NOTIFIER_INIT; MOZ_ASSERT(mPointList, "Expecting non-null pointList"); mEmptyOrOldValue = mPointList->Element()->WillChangePointList(); } ~AutoChangePointListNotifier() { mPointList->Element()->DidChangePointList(mEmptyOrOldValue); if (mPointList->AttrIsAnimating()) { mPointList->Element()->AnimationNeedsResample(); } } private: DOMSVGPointList* const mPointList; nsAttrValue mEmptyOrOldValue; MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER }; /* static */ already_AddRefed<DOMSVGPointList> DOMSVGPointList::GetDOMWrapper(void *aList, nsSVGElement *aElement, bool aIsAnimValList) { RefPtr<DOMSVGPointList> wrapper = SVGPointListTearoffTable().GetTearoff(aList); if (!wrapper) { wrapper = new DOMSVGPointList(aElement, aIsAnimValList); SVGPointListTearoffTable().AddTearoff(aList, wrapper); } return wrapper.forget(); } /* static */ DOMSVGPointList* DOMSVGPointList::GetDOMWrapperIfExists(void *aList) { return SVGPointListTearoffTable().GetTearoff(aList); } DOMSVGPointList::~DOMSVGPointList() { // There are now no longer any references to us held by script or list items. // Note we must use GetAnimValKey/GetBaseValKey here, NOT InternalList()! void *key = mIsAnimValList ? InternalAList().GetAnimValKey() : InternalAList().GetBaseValKey(); SVGPointListTearoffTable().RemoveTearoff(key); } JSObject* DOMSVGPointList::WrapObject(JSContext *cx, JS::Handle<JSObject*> aGivenProto) { return mozilla::dom::SVGPointListBinding::Wrap(cx, this, aGivenProto); } void DOMSVGPointList::InternalListWillChangeTo(const SVGPointList& aNewValue) { // When the number of items in our internal counterpart changes, we MUST stay // in sync. Everything in the scary comment in // DOMSVGLengthList::InternalBaseValListWillChangeTo applies here too! uint32_t oldLength = mItems.Length(); uint32_t newLength = aNewValue.Length(); if (newLength > nsISVGPoint::MaxListIndex()) { // It's safe to get out of sync with our internal list as long as we have // FEWER items than it does. newLength = nsISVGPoint::MaxListIndex(); } RefPtr<DOMSVGPointList> kungFuDeathGrip; if (newLength < oldLength) { // RemovingFromList() might clear last reference to |this|. // Retain a temporary reference to keep from dying before returning. kungFuDeathGrip = this; } // If our length will decrease, notify the items that will be removed: for (uint32_t i = newLength; i < oldLength; ++i) { if (mItems[i]) { mItems[i]->RemovingFromList(); } } if (!mItems.SetLength(newLength, fallible)) { // We silently ignore SetLength OOM failure since being out of sync is safe // so long as we have *fewer* items than our internal list. mItems.Clear(); return; } // If our length has increased, null out the new pointers: for (uint32_t i = oldLength; i < newLength; ++i) { mItems[i] = nullptr; } } bool DOMSVGPointList::AttrIsAnimating() const { return InternalAList().IsAnimating(); } bool DOMSVGPointList::AnimListMirrorsBaseList() const { return GetDOMWrapperIfExists(InternalAList().GetAnimValKey()) && !AttrIsAnimating(); } SVGPointList& DOMSVGPointList::InternalList() const { SVGAnimatedPointList *alist = mElement->GetAnimatedPointList(); return mIsAnimValList && alist->IsAnimating() ? *alist->mAnimVal : alist->mBaseVal; } SVGAnimatedPointList& DOMSVGPointList::InternalAList() const { MOZ_ASSERT(mElement->GetAnimatedPointList(), "Internal error"); return *mElement->GetAnimatedPointList(); } // ---------------------------------------------------------------------------- // nsIDOMSVGPointList implementation: void DOMSVGPointList::Clear(ErrorResult& aError) { if (IsAnimValList()) { aError.Throw(NS_ERROR_DOM_NO_MODIFICATION_ALLOWED_ERR); return; } if (LengthNoFlush() > 0) { AutoChangePointListNotifier notifier(this); // DOM list items that are to be removed must be removed before we change // the internal list, otherwise they wouldn't be able to copy their // internal counterparts' values! InternalListWillChangeTo(SVGPointList()); // clears mItems if (!AttrIsAnimating()) { // The anim val list is in sync with the base val list DOMSVGPointList *animList = GetDOMWrapperIfExists(InternalAList().GetAnimValKey()); if (animList) { animList->InternalListWillChangeTo(SVGPointList()); // clears its mItems } } InternalList().Clear(); } } already_AddRefed<nsISVGPoint> DOMSVGPointList::Initialize(nsISVGPoint& aNewItem, ErrorResult& aError) { if (IsAnimValList()) { aError.Throw(NS_ERROR_DOM_NO_MODIFICATION_ALLOWED_ERR); return nullptr; } // If aNewItem is already in a list we should insert a clone of aNewItem, // and for consistency, this should happen even if *this* is the list that // aNewItem is currently in. Note that in the case of aNewItem being in this // list, the Clear() call before the InsertItemBefore() call would remove it // from this list, and so the InsertItemBefore() call would not insert a // clone of aNewItem, it would actually insert aNewItem. To prevent that // from happening we have to do the clone here, if necessary. nsCOMPtr<nsISVGPoint> domItem = &aNewItem; if (domItem->HasOwner() || domItem->IsReadonly() || domItem->IsTranslatePoint()) { domItem = domItem->Copy(); // must do this before changing anything! } ErrorResult rv; Clear(rv); MOZ_ASSERT(!rv.Failed()); return InsertItemBefore(*domItem, 0, aError); } already_AddRefed<nsISVGPoint> DOMSVGPointList::GetItem(uint32_t index, ErrorResult& error) { bool found; RefPtr<nsISVGPoint> item = IndexedGetter(index, found, error); if (!found) { error.Throw(NS_ERROR_DOM_INDEX_SIZE_ERR); } return item.forget(); } already_AddRefed<nsISVGPoint> DOMSVGPointList::IndexedGetter(uint32_t aIndex, bool& aFound, ErrorResult& aError) { if (IsAnimValList()) { Element()->FlushAnimations(); } aFound = aIndex < LengthNoFlush(); if (aFound) { return GetItemAt(aIndex); } return nullptr; } already_AddRefed<nsISVGPoint> DOMSVGPointList::InsertItemBefore(nsISVGPoint& aNewItem, uint32_t aIndex, ErrorResult& aError) { if (IsAnimValList()) { aError.Throw(NS_ERROR_DOM_NO_MODIFICATION_ALLOWED_ERR); return nullptr; } aIndex = std::min(aIndex, LengthNoFlush()); if (aIndex >= nsISVGPoint::MaxListIndex()) { aError.Throw(NS_ERROR_DOM_INDEX_SIZE_ERR); return nullptr; } nsCOMPtr<nsISVGPoint> domItem = &aNewItem; if (domItem->HasOwner() || domItem->IsReadonly() || domItem->IsTranslatePoint()) { domItem = domItem->Copy(); // must do this before changing anything! } // Ensure we have enough memory so we can avoid complex error handling below: if (!mItems.SetCapacity(mItems.Length() + 1, fallible) || !InternalList().SetCapacity(InternalList().Length() + 1)) { aError.Throw(NS_ERROR_OUT_OF_MEMORY); return nullptr; } if (AnimListMirrorsBaseList()) { DOMSVGPointList *animVal = GetDOMWrapperIfExists(InternalAList().GetAnimValKey()); MOZ_ASSERT(animVal, "animVal must be a valid pointer"); if (!animVal->mItems.SetCapacity( animVal->mItems.Length() + 1, fallible)) { aError.Throw(NS_ERROR_OUT_OF_MEMORY); return nullptr; } } AutoChangePointListNotifier notifier(this); // Now that we know we're inserting, keep animVal list in sync as necessary. MaybeInsertNullInAnimValListAt(aIndex); InternalList().InsertItem(aIndex, domItem->ToSVGPoint()); MOZ_ALWAYS_TRUE(mItems.InsertElementAt(aIndex, domItem, fallible)); // This MUST come after the insertion into InternalList(), or else under the // insertion into InternalList() the values read from domItem would be bad // data from InternalList() itself!: domItem->InsertingIntoList(this, aIndex, IsAnimValList()); UpdateListIndicesFromIndex(mItems, aIndex + 1); return domItem.forget(); } already_AddRefed<nsISVGPoint> DOMSVGPointList::ReplaceItem(nsISVGPoint& aNewItem, uint32_t aIndex, ErrorResult& aError) { if (IsAnimValList()) { aError.Throw(NS_ERROR_DOM_NO_MODIFICATION_ALLOWED_ERR); return nullptr; } if (aIndex >= LengthNoFlush()) { aError.Throw(NS_ERROR_DOM_INDEX_SIZE_ERR); return nullptr; } nsCOMPtr<nsISVGPoint> domItem = &aNewItem; if (domItem->HasOwner() || domItem->IsReadonly() || domItem->IsTranslatePoint()) { domItem = domItem->Copy(); // must do this before changing anything! } AutoChangePointListNotifier notifier(this); if (mItems[aIndex]) { // Notify any existing DOM item of removal *before* modifying the lists so // that the DOM item can copy the *old* value at its index: mItems[aIndex]->RemovingFromList(); } InternalList()[aIndex] = domItem->ToSVGPoint(); mItems[aIndex] = domItem; // This MUST come after the ToSVGPoint() call, otherwise that call // would end up reading bad data from InternalList()! domItem->InsertingIntoList(this, aIndex, IsAnimValList()); return domItem.forget(); } already_AddRefed<nsISVGPoint> DOMSVGPointList::RemoveItem(uint32_t aIndex, ErrorResult& aError) { if (IsAnimValList()) { aError.Throw(NS_ERROR_DOM_NO_MODIFICATION_ALLOWED_ERR); return nullptr; } if (aIndex >= LengthNoFlush()) { aError.Throw(NS_ERROR_DOM_INDEX_SIZE_ERR); return nullptr; } AutoChangePointListNotifier notifier(this); // Now that we know we're removing, keep animVal list in sync as necessary. // Do this *before* touching InternalList() so the removed item can get its // internal value. MaybeRemoveItemFromAnimValListAt(aIndex); // We have to return the removed item, so get it, creating it if necessary: RefPtr<nsISVGPoint> result = GetItemAt(aIndex); // Notify the DOM item of removal *before* modifying the lists so that the // DOM item can copy its *old* value: mItems[aIndex]->RemovingFromList(); InternalList().RemoveItem(aIndex); mItems.RemoveElementAt(aIndex); UpdateListIndicesFromIndex(mItems, aIndex); return result.forget(); } already_AddRefed<nsISVGPoint> DOMSVGPointList::GetItemAt(uint32_t aIndex) { MOZ_ASSERT(aIndex < mItems.Length()); if (!mItems[aIndex]) { mItems[aIndex] = new DOMSVGPoint(this, aIndex, IsAnimValList()); } RefPtr<nsISVGPoint> result = mItems[aIndex]; return result.forget(); } void DOMSVGPointList::MaybeInsertNullInAnimValListAt(uint32_t aIndex) { MOZ_ASSERT(!IsAnimValList(), "call from baseVal to animVal"); if (!AnimListMirrorsBaseList()) { return; } // The anim val list is in sync with the base val list DOMSVGPointList *animVal = GetDOMWrapperIfExists(InternalAList().GetAnimValKey()); MOZ_ASSERT(animVal, "AnimListMirrorsBaseList() promised a non-null animVal"); MOZ_ASSERT(animVal->mItems.Length() == mItems.Length(), "animVal list not in sync!"); MOZ_ALWAYS_TRUE(animVal->mItems.InsertElementAt(aIndex, nullptr, fallible)); UpdateListIndicesFromIndex(animVal->mItems, aIndex + 1); } void DOMSVGPointList::MaybeRemoveItemFromAnimValListAt(uint32_t aIndex) { MOZ_ASSERT(!IsAnimValList(), "call from baseVal to animVal"); if (!AnimListMirrorsBaseList()) { return; } // This needs to be a strong reference; otherwise, the RemovingFromList call // below might drop the last reference to animVal before we're done with it. RefPtr<DOMSVGPointList> animVal = GetDOMWrapperIfExists(InternalAList().GetAnimValKey()); MOZ_ASSERT(animVal, "AnimListMirrorsBaseList() promised a non-null animVal"); MOZ_ASSERT(animVal->mItems.Length() == mItems.Length(), "animVal list not in sync!"); if (animVal->mItems[aIndex]) { animVal->mItems[aIndex]->RemovingFromList(); } animVal->mItems.RemoveElementAt(aIndex); UpdateListIndicesFromIndex(animVal->mItems, aIndex); } } // namespace mozilla