/* -*- 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 "DOMSVGLengthList.h" #include "DOMSVGLength.h" #include "nsError.h" #include "SVGAnimatedLengthList.h" #include "nsCOMPtr.h" #include "mozilla/dom/SVGLengthListBinding.h" #include <algorithm> // See the comment in this file's header. // local helper functions namespace { using mozilla::DOMSVGLength; void UpdateListIndicesFromIndex(FallibleTArray<DOMSVGLength*>& 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 { // We could use NS_IMPL_CYCLE_COLLECTION(, except that in Unlink() we need to // clear our DOMSVGAnimatedLengthList's weak ref to us to be safe. (The other // option would be to not unlink and rely on the breaking of the other edges in // the cycle, as NS_SVG_VAL_IMPL_CYCLE_COLLECTION does.) NS_IMPL_CYCLE_COLLECTION_CLASS(DOMSVGLengthList) NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(DOMSVGLengthList) if (tmp->mAList) { if (tmp->IsAnimValList()) { tmp->mAList->mAnimVal = nullptr; } else { tmp->mAList->mBaseVal = nullptr; } NS_IMPL_CYCLE_COLLECTION_UNLINK(mAList) } NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER NS_IMPL_CYCLE_COLLECTION_UNLINK_END NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(DOMSVGLengthList) NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mAList) NS_IMPL_CYCLE_COLLECTION_TRAVERSE_SCRIPT_OBJECTS NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(DOMSVGLengthList) NS_IMPL_CYCLE_COLLECTION_TRACE_PRESERVED_WRAPPER NS_IMPL_CYCLE_COLLECTION_TRACE_END NS_IMPL_CYCLE_COLLECTING_ADDREF(DOMSVGLengthList) NS_IMPL_CYCLE_COLLECTING_RELEASE(DOMSVGLengthList) NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(DOMSVGLengthList) NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY NS_INTERFACE_MAP_ENTRY(nsISupports) NS_INTERFACE_MAP_END JSObject* DOMSVGLengthList::WrapObject(JSContext *cx, JS::Handle<JSObject*> aGivenProto) { return mozilla::dom::SVGLengthListBinding::Wrap(cx, this, aGivenProto); } //---------------------------------------------------------------------- // Helper class: AutoChangeLengthListNotifier // Stack-based helper class to pair calls to WillChangeLengthList and // DidChangeLengthList. class MOZ_RAII AutoChangeLengthListNotifier { public: explicit AutoChangeLengthListNotifier(DOMSVGLengthList* aLengthList MOZ_GUARD_OBJECT_NOTIFIER_PARAM) : mLengthList(aLengthList) { MOZ_GUARD_OBJECT_NOTIFIER_INIT; MOZ_ASSERT(mLengthList, "Expecting non-null lengthList"); mEmptyOrOldValue = mLengthList->Element()->WillChangeLengthList(mLengthList->AttrEnum()); } ~AutoChangeLengthListNotifier() { mLengthList->Element()->DidChangeLengthList(mLengthList->AttrEnum(), mEmptyOrOldValue); if (mLengthList->IsAnimating()) { mLengthList->Element()->AnimationNeedsResample(); } } private: DOMSVGLengthList* const mLengthList; nsAttrValue mEmptyOrOldValue; MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER }; void DOMSVGLengthList::InternalListLengthWillChange(uint32_t aNewLength) { uint32_t oldLength = mItems.Length(); if (aNewLength > DOMSVGLength::MaxListIndex()) { // It's safe to get out of sync with our internal list as long as we have // FEWER items than it does. aNewLength = DOMSVGLength::MaxListIndex(); } RefPtr<DOMSVGLengthList> kungFuDeathGrip; if (aNewLength < 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 = aNewLength; i < oldLength; ++i) { if (mItems[i]) { mItems[i]->RemovingFromList(); } } if (!mItems.SetLength(aNewLength, 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 < aNewLength; ++i) { mItems[i] = nullptr; } } SVGLengthList& DOMSVGLengthList::InternalList() const { SVGAnimatedLengthList *alist = Element()->GetAnimatedLengthList(AttrEnum()); return IsAnimValList() && alist->mAnimVal ? *alist->mAnimVal : alist->mBaseVal; } // ---------------------------------------------------------------------------- void DOMSVGLengthList::Clear(ErrorResult& aError) { if (IsAnimValList()) { aError.Throw(NS_ERROR_DOM_NO_MODIFICATION_ALLOWED_ERR); return; } if (LengthNoFlush() > 0) { AutoChangeLengthListNotifier notifier(this); // Notify any existing DOM items of removal *before* truncating the lists // so that they can find their SVGLength internal counterparts and copy // their values. This also notifies the animVal list: mAList->InternalBaseValListWillChangeTo(SVGLengthList()); mItems.Clear(); InternalList().Clear(); } } already_AddRefed<DOMSVGLength> DOMSVGLengthList::Initialize(DOMSVGLength& newItem, ErrorResult& error) { if (IsAnimValList()) { error.Throw(NS_ERROR_DOM_NO_MODIFICATION_ALLOWED_ERR); return nullptr; } // If newItem already has an owner or is reflecting an attribute, we should // insert a clone of newItem, and for consistency, this should happen even if // *this* is the list that newItem is currently in. Note that in the case of // newItem 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 newItem, it would actually insert newItem. To // prevent that from happening we have to do the clone here, if necessary. RefPtr<DOMSVGLength> domItem = &newItem; if (!domItem) { error.Throw(NS_ERROR_DOM_SVG_WRONG_TYPE_ERR); return nullptr; } if (domItem->HasOwner() || domItem->IsReflectingAttribute()) { domItem = domItem->Copy(); } ErrorResult rv; Clear(rv); MOZ_ASSERT(!rv.Failed()); return InsertItemBefore(*domItem, 0, error); } already_AddRefed<DOMSVGLength> DOMSVGLengthList::GetItem(uint32_t index, ErrorResult& error) { bool found; RefPtr<DOMSVGLength> item = IndexedGetter(index, found, error); if (!found) { error.Throw(NS_ERROR_DOM_INDEX_SIZE_ERR); } return item.forget(); } already_AddRefed<DOMSVGLength> DOMSVGLengthList::IndexedGetter(uint32_t index, bool& found, ErrorResult& error) { if (IsAnimValList()) { Element()->FlushAnimations(); } found = index < LengthNoFlush(); if (found) { return GetItemAt(index); } return nullptr; } already_AddRefed<DOMSVGLength> DOMSVGLengthList::InsertItemBefore(DOMSVGLength& newItem, uint32_t index, ErrorResult& error) { if (IsAnimValList()) { error.Throw(NS_ERROR_DOM_NO_MODIFICATION_ALLOWED_ERR); return nullptr; } index = std::min(index, LengthNoFlush()); if (index >= DOMSVGLength::MaxListIndex()) { error.Throw(NS_ERROR_DOM_INDEX_SIZE_ERR); return nullptr; } RefPtr<DOMSVGLength> domItem = &newItem; if (!domItem) { error.Throw(NS_ERROR_DOM_SVG_WRONG_TYPE_ERR); return nullptr; } if (domItem->HasOwner() || domItem->IsReflectingAttribute()) { 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)) { error.Throw(NS_ERROR_OUT_OF_MEMORY); return nullptr; } if (AnimListMirrorsBaseList()) { if (!mAList->mAnimVal->mItems.SetCapacity( mAList->mAnimVal->mItems.Length() + 1, fallible)) { error.Throw(NS_ERROR_OUT_OF_MEMORY); return nullptr; } } AutoChangeLengthListNotifier notifier(this); // Now that we know we're inserting, keep animVal list in sync as necessary. MaybeInsertNullInAnimValListAt(index); InternalList().InsertItem(index, domItem->ToSVGLength()); MOZ_ALWAYS_TRUE(mItems.InsertElementAt(index, domItem.get(), 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, AttrEnum(), index, IsAnimValList()); UpdateListIndicesFromIndex(mItems, index + 1); return domItem.forget(); } already_AddRefed<DOMSVGLength> DOMSVGLengthList::ReplaceItem(DOMSVGLength& newItem, uint32_t index, ErrorResult& error) { if (IsAnimValList()) { error.Throw(NS_ERROR_DOM_NO_MODIFICATION_ALLOWED_ERR); return nullptr; } RefPtr<DOMSVGLength> domItem = &newItem; if (!domItem) { error.Throw(NS_ERROR_DOM_SVG_WRONG_TYPE_ERR); return nullptr; } if (index >= LengthNoFlush()) { error.Throw(NS_ERROR_DOM_INDEX_SIZE_ERR); return nullptr; } if (domItem->HasOwner() || domItem->IsReflectingAttribute()) { domItem = domItem->Copy(); // must do this before changing anything! } AutoChangeLengthListNotifier notifier(this); if (mItems[index]) { // 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[index]->RemovingFromList(); } InternalList()[index] = domItem->ToSVGLength(); mItems[index] = domItem; // This MUST come after the ToSVGPoint() call, otherwise that call // would end up reading bad data from InternalList()! domItem->InsertingIntoList(this, AttrEnum(), index, IsAnimValList()); return domItem.forget(); } already_AddRefed<DOMSVGLength> DOMSVGLengthList::RemoveItem(uint32_t index, ErrorResult& error) { if (IsAnimValList()) { error.Throw(NS_ERROR_DOM_NO_MODIFICATION_ALLOWED_ERR); return nullptr; } if (index >= LengthNoFlush()) { error.Throw(NS_ERROR_DOM_INDEX_SIZE_ERR); return nullptr; } AutoChangeLengthListNotifier 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(index); // We have to return the removed item, so get it, creating it if necessary: nsCOMPtr<DOMSVGLength> result = GetItemAt(index); // Notify the DOM item of removal *before* modifying the lists so that the // DOM item can copy its *old* value: mItems[index]->RemovingFromList(); InternalList().RemoveItem(index); mItems.RemoveElementAt(index); UpdateListIndicesFromIndex(mItems, index); return result.forget(); } already_AddRefed<DOMSVGLength> DOMSVGLengthList::GetItemAt(uint32_t aIndex) { MOZ_ASSERT(aIndex < mItems.Length()); if (!mItems[aIndex]) { mItems[aIndex] = new DOMSVGLength(this, AttrEnum(), aIndex, IsAnimValList()); } RefPtr<DOMSVGLength> result = mItems[aIndex]; return result.forget(); } void DOMSVGLengthList::MaybeInsertNullInAnimValListAt(uint32_t aIndex) { MOZ_ASSERT(!IsAnimValList(), "call from baseVal to animVal"); if (!AnimListMirrorsBaseList()) { return; } DOMSVGLengthList* animVal = mAList->mAnimVal; 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 DOMSVGLengthList::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<DOMSVGLengthList> animVal = mAList->mAnimVal; 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