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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 19:33:14 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 19:33:14 +0000 |
commit | 36d22d82aa202bb199967e9512281e9a53db42c9 (patch) | |
tree | 105e8c98ddea1c1e4784a60a5a6410fa416be2de /dom/svg/DOMSVGPathSegList.cpp | |
parent | Initial commit. (diff) | |
download | firefox-esr-upstream.tar.xz firefox-esr-upstream.zip |
Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'dom/svg/DOMSVGPathSegList.cpp')
-rw-r--r-- | dom/svg/DOMSVGPathSegList.cpp | 535 |
1 files changed, 535 insertions, 0 deletions
diff --git a/dom/svg/DOMSVGPathSegList.cpp b/dom/svg/DOMSVGPathSegList.cpp new file mode 100644 index 0000000000..b931fcf599 --- /dev/null +++ b/dom/svg/DOMSVGPathSegList.cpp @@ -0,0 +1,535 @@ +/* -*- 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 "DOMSVGPathSegList.h" + +#include "DOMSVGPathSeg.h" +#include "nsError.h" +#include "SVGAnimatedPathSegList.h" +#include "SVGAttrTearoffTable.h" +#include "SVGPathSegUtils.h" +#include "mozilla/dom/SVGElement.h" +#include "mozilla/dom/SVGPathSegListBinding.h" +#include "mozilla/RefPtr.h" + +// See the comment in this file's header. + +namespace mozilla::dom { + +static inline SVGAttrTearoffTable<void, DOMSVGPathSegList>& +SVGPathSegListTearoffTable() { + static SVGAttrTearoffTable<void, DOMSVGPathSegList> + sSVGPathSegListTearoffTable; + return sSVGPathSegListTearoffTable; +} + +NS_IMPL_CYCLE_COLLECTION_CLASS(DOMSVGPathSegList) + +NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(DOMSVGPathSegList) + // 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. + tmp->RemoveFromTearoffTable(); + NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER +NS_IMPL_CYCLE_COLLECTION_UNLINK_END +NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(DOMSVGPathSegList) + NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mElement) +NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END +NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(DOMSVGPathSegList) + NS_IMPL_CYCLE_COLLECTION_TRACE_PRESERVED_WRAPPER +NS_IMPL_CYCLE_COLLECTION_TRACE_END + +NS_IMPL_CYCLE_COLLECTING_ADDREF(DOMSVGPathSegList) +NS_IMPL_CYCLE_COLLECTING_RELEASE(DOMSVGPathSegList) + +NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(DOMSVGPathSegList) + NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY + NS_INTERFACE_MAP_ENTRY(nsISupports) +NS_INTERFACE_MAP_END + +/* static */ +already_AddRefed<DOMSVGPathSegList> DOMSVGPathSegList::GetDOMWrapper( + void* aList, SVGElement* aElement, bool aIsAnimValList) { + RefPtr<DOMSVGPathSegList> wrapper = + SVGPathSegListTearoffTable().GetTearoff(aList); + if (!wrapper) { + wrapper = new DOMSVGPathSegList(aElement, aIsAnimValList); + SVGPathSegListTearoffTable().AddTearoff(aList, wrapper); + } + return wrapper.forget(); +} + +/* static */ +DOMSVGPathSegList* DOMSVGPathSegList::GetDOMWrapperIfExists(void* aList) { + return SVGPathSegListTearoffTable().GetTearoff(aList); +} + +void DOMSVGPathSegList::RemoveFromTearoffTable() { + // 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(); + SVGPathSegListTearoffTable().RemoveTearoff(key); +} + +DOMSVGPathSegList::~DOMSVGPathSegList() { RemoveFromTearoffTable(); } + +JSObject* DOMSVGPathSegList::WrapObject(JSContext* cx, + JS::Handle<JSObject*> aGivenProto) { + return mozilla::dom::SVGPathSegList_Binding::Wrap(cx, this, aGivenProto); +} + +void DOMSVGPathSegList::InternalListWillChangeTo(const SVGPathData& 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 just as + // much, but we have the additional issue that failing to stay in sync would + // mean that - assuming we aren't reading bad memory - we would likely end up + // decoding command types from argument floats when looking in our + // SVGPathData's data array! Either way, we'll likely then go down + // MOZ_ASSERT_UNREACHABLE code paths, or end up reading/setting more bad + // memory!! + + // The only time that our other DOM list type implementations remove items is + // if those items become surplus items due to an attribute change or SMIL + // animation sample shortening the list. In general though, they try to keep + // their existing DOM items, even when things change. To be consistent, we'd + // really like to do the same thing. However, because different types of path + // segment correspond to different DOMSVGPathSeg subclasses, the type of + // items in our list are generally not the same, which makes this harder for + // us. We have to remove DOM segments if their type is not the same as the + // type of the new internal segment at their index. + // + // We also need to sync up mInternalDataIndex, but since we need to loop over + // all the items in the new list checking types anyway, that's almost + // insignificant in terms of overhead. + // + // Note that this method is called on every single SMIL animation resample + // and we have no way to short circuit the overhead since we don't have a + // way to tell if the call is due to a new animation, or a resample of an + // existing animation (when the number and type of items would be the same). + // (Note that a new animation could start overriding an existing animation at + // any time, so checking IsAnimating() wouldn't work.) Because we get called + // on every sample, it would not be acceptable alternative to throw away all + // our items and let them be recreated lazily, since that would break what + // script sees! + + uint32_t length = mItems.Length(); + uint32_t index = 0; + + uint32_t dataLength = aNewValue.mData.Length(); + uint32_t dataIndex = 0; // index into aNewValue's raw data array + + uint32_t newSegType; + + RefPtr<DOMSVGPathSegList> kungFuDeathGrip; + if (length) { + // RemovingFromList() might clear last reference to |this|. + // Retain a temporary reference to keep from dying before returning. + // + // NOTE: For path-seg lists (unlike other list types), we have to do this + // *whenever our list is nonempty* (even if we're growing in length). + // That's because the path-seg-type of any segment could differ between old + // list vs. new list, which will make us destroy & recreate that segment, + // which could remove the last reference to us. + // + // (We explicitly *don't* want to create a kungFuDeathGrip in the length=0 + // case, though, because we do hit this code inside our constructor before + // any other owning references have been added, and at that point, the + // deathgrip-removal would make us die before we exit our constructor.) + kungFuDeathGrip = this; + } + + while (index < length && dataIndex < dataLength) { + newSegType = SVGPathSegUtils::DecodeType(aNewValue.mData[dataIndex]); + if (ItemAt(index) && ItemAt(index)->Type() != newSegType) { + ItemAt(index)->RemovingFromList(); + ItemAt(index) = nullptr; + } + // Only after the RemovingFromList() can we touch mInternalDataIndex! + mItems[index].mInternalDataIndex = dataIndex; + ++index; + dataIndex += 1 + SVGPathSegUtils::ArgCountForType(newSegType); + } + + MOZ_ASSERT((index == length && dataIndex <= dataLength) || + (index <= length && dataIndex == dataLength), + "very bad - list corruption?"); + + if (index < length) { + // aNewValue has fewer items than our previous internal counterpart + + uint32_t newLength = index; + + // Remove excess items from the list: + for (; index < length; ++index) { + if (ItemAt(index)) { + ItemAt(index)->RemovingFromList(); + ItemAt(index) = nullptr; + } + } + + // Only now may we truncate mItems + mItems.TruncateLength(newLength); + } else if (dataIndex < dataLength) { + // aNewValue has more items than our previous internal counterpart + + // Sync mItems: + while (dataIndex < dataLength) { + if (mItems.Length() && + mItems.Length() - 1 > DOMSVGPathSeg::MaxListIndex()) { + // It's safe to get out of sync with our internal list as long as we + // have FEWER items than it does. + return; + } + if (!mItems.AppendElement(ItemProxy(nullptr, dataIndex), fallible)) { + // OOM + ErrorResult rv; + Clear(rv); + MOZ_ASSERT(!rv.Failed()); + return; + } + dataIndex += + 1 + SVGPathSegUtils::ArgCountForType( + SVGPathSegUtils::DecodeType(aNewValue.mData[dataIndex])); + } + } + + MOZ_ASSERT(dataIndex == dataLength, "Serious processing error"); + MOZ_ASSERT(index == length, "Serious counting error"); +} + +bool DOMSVGPathSegList::AttrIsAnimating() const { + return InternalAList().IsAnimating(); +} + +bool DOMSVGPathSegList::AnimListMirrorsBaseList() const { + return GetDOMWrapperIfExists(InternalAList().GetAnimValKey()) && + !AttrIsAnimating(); +} + +SVGPathData& DOMSVGPathSegList::InternalList() const { + SVGAnimatedPathSegList* alist = mElement->GetAnimPathSegList(); + return mIsAnimValList && alist->IsAnimating() ? *alist->mAnimVal + : alist->mBaseVal; +} + +SVGAnimatedPathSegList& DOMSVGPathSegList::InternalAList() const { + MOZ_ASSERT(mElement->GetAnimPathSegList(), "Internal error"); + return *mElement->GetAnimPathSegList(); +} + +// ---------------------------------------------------------------------------- +// nsIDOMSVGPathSegList implementation: + +void DOMSVGPathSegList::Clear(ErrorResult& aError) { + if (IsAnimValList()) { + aError.Throw(NS_ERROR_DOM_NO_MODIFICATION_ALLOWED_ERR); + return; + } + + if (LengthNoFlush() > 0) { + AutoChangePathSegListNotifier 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(SVGPathData()); // clears mItems + + if (!AttrIsAnimating()) { + // The anim val list is in sync with the base val list + DOMSVGPathSegList* animList = + GetDOMWrapperIfExists(InternalAList().GetAnimValKey()); + if (animList) { + animList->InternalListWillChangeTo(SVGPathData()); // clears its mItems + } + } + + InternalList().Clear(); + } +} + +already_AddRefed<DOMSVGPathSeg> DOMSVGPathSegList::Initialize( + DOMSVGPathSeg& 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. + + RefPtr<DOMSVGPathSeg> domItem = &aNewItem; + if (aNewItem.HasOwner()) { + domItem = aNewItem.Clone(); + } + + Clear(aError); + MOZ_ASSERT(!aError.Failed(), "How could this fail?"); + return InsertItemBefore(*domItem, 0, aError); +} + +already_AddRefed<DOMSVGPathSeg> DOMSVGPathSegList::GetItem(uint32_t index, + ErrorResult& error) { + bool found; + RefPtr<DOMSVGPathSeg> item = IndexedGetter(index, found, error); + if (!found) { + error.Throw(NS_ERROR_DOM_INDEX_SIZE_ERR); + } + return item.forget(); +} + +already_AddRefed<DOMSVGPathSeg> DOMSVGPathSegList::IndexedGetter( + uint32_t aIndex, bool& aFound, ErrorResult& aError) { + if (IsAnimValList()) { + Element()->FlushAnimations(); + } + aFound = aIndex < LengthNoFlush(); + if (aFound) { + return GetItemAt(aIndex); + } + return nullptr; +} + +already_AddRefed<DOMSVGPathSeg> DOMSVGPathSegList::InsertItemBefore( + DOMSVGPathSeg& aNewItem, uint32_t aIndex, ErrorResult& aError) { + if (IsAnimValList()) { + aError.Throw(NS_ERROR_DOM_NO_MODIFICATION_ALLOWED_ERR); + return nullptr; + } + + uint32_t internalIndex; + if (aIndex < LengthNoFlush()) { + internalIndex = mItems[aIndex].mInternalDataIndex; + } else { + aIndex = LengthNoFlush(); + internalIndex = InternalList().mData.Length(); + } + if (aIndex >= DOMSVGPathSeg::MaxListIndex()) { + aError.Throw(NS_ERROR_DOM_INDEX_SIZE_ERR); + return nullptr; + } + + RefPtr<DOMSVGPathSeg> domItem = &aNewItem; + if (domItem->HasOwner()) { + domItem = domItem->Clone(); // must do this before changing anything! + } + + uint32_t argCount = SVGPathSegUtils::ArgCountForType(domItem->Type()); + + // Ensure we have enough memory so we can avoid complex error handling below: + if (!mItems.SetCapacity(mItems.Length() + 1, fallible) || + !InternalList().mData.SetCapacity( + InternalList().mData.Length() + 1 + argCount, fallible)) { + aError.Throw(NS_ERROR_OUT_OF_MEMORY); + return nullptr; + } + if (AnimListMirrorsBaseList()) { + DOMSVGPathSegList* animVal = + GetDOMWrapperIfExists(InternalAList().GetAnimValKey()); + MOZ_ASSERT(animVal, "animVal should be a valid pointer"); + if (!animVal->mItems.SetCapacity(animVal->mItems.Length() + 1, fallible)) { + aError.Throw(NS_ERROR_OUT_OF_MEMORY); + return nullptr; + } + } + + AutoChangePathSegListNotifier notifier(this); + // Now that we know we're inserting, keep animVal list in sync as necessary. + MaybeInsertNullInAnimValListAt(aIndex, internalIndex, argCount); + + float segAsRaw[1 + NS_SVG_PATH_SEG_MAX_ARGS]; + domItem->ToSVGPathSegEncodedData(segAsRaw); + + MOZ_ALWAYS_TRUE(InternalList().mData.InsertElementsAt( + internalIndex, segAsRaw, 1 + argCount, fallible)); + MOZ_ALWAYS_TRUE(mItems.InsertElementAt( + aIndex, ItemProxy(domItem.get(), internalIndex), 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(aIndex + 1, argCount + 1); + + return domItem.forget(); +} + +already_AddRefed<DOMSVGPathSeg> DOMSVGPathSegList::ReplaceItem( + DOMSVGPathSeg& 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; + } + + RefPtr<DOMSVGPathSeg> domItem = &aNewItem; + if (domItem->HasOwner()) { + domItem = domItem->Clone(); // must do this before changing anything! + } + + AutoChangePathSegListNotifier notifier(this); + if (ItemAt(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: + ItemAt(aIndex)->RemovingFromList(); + } + + uint32_t internalIndex = mItems[aIndex].mInternalDataIndex; + // We use InternalList() to get oldArgCount since we may not have a DOM + // wrapper at the index being replaced. + uint32_t oldType = + SVGPathSegUtils::DecodeType(InternalList().mData[internalIndex]); + + // NOTE: ArgCountForType returns a (small) unsigned value, but we're + // intentionally putting it in a signed variable, because we're going to + // subtract these values and might produce something negative. + int32_t oldArgCount = SVGPathSegUtils::ArgCountForType(oldType); + int32_t newArgCount = SVGPathSegUtils::ArgCountForType(domItem->Type()); + + float segAsRaw[1 + NS_SVG_PATH_SEG_MAX_ARGS]; + domItem->ToSVGPathSegEncodedData(segAsRaw); + + if (!InternalList().mData.ReplaceElementsAt(internalIndex, 1 + oldArgCount, + segAsRaw, 1 + newArgCount, + fallible)) { + aError.Throw(NS_ERROR_OUT_OF_MEMORY); + return nullptr; + } + ItemAt(aIndex) = domItem; + + // This MUST come after the ToSVGPathSegEncodedData call, otherwise that call + // would end up reading bad data from InternalList()! + domItem->InsertingIntoList(this, aIndex, IsAnimValList()); + + int32_t delta = newArgCount - oldArgCount; + if (delta != 0) { + for (uint32_t i = aIndex + 1; i < LengthNoFlush(); ++i) { + mItems[i].mInternalDataIndex += delta; + } + } + + return domItem.forget(); +} + +already_AddRefed<DOMSVGPathSeg> DOMSVGPathSegList::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; + } + // We have to return the removed item, so get it, creating it if necessary: + RefPtr<DOMSVGPathSeg> result = GetItemAt(aIndex); + + AutoChangePathSegListNotifier notifier(this); + // Notify the DOM item of removal *before* modifying the lists so that the + // DOM item can copy its *old* value: + ItemAt(aIndex)->RemovingFromList(); + + uint32_t internalIndex = mItems[aIndex].mInternalDataIndex; + uint32_t segType = + SVGPathSegUtils::DecodeType(InternalList().mData[internalIndex]); + // NOTE: ArgCountForType returns a (small) unsigned value, but we're + // intentionally putting it in a signed value, because we're going to + // negate it, and you can't negate an unsigned value. + int32_t argCount = SVGPathSegUtils::ArgCountForType(segType); + + // 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, argCount); + + InternalList().mData.RemoveElementsAt(internalIndex, 1 + argCount); + mItems.RemoveElementAt(aIndex); + + UpdateListIndicesFromIndex(aIndex, -(argCount + 1)); + + return result.forget(); +} + +already_AddRefed<DOMSVGPathSeg> DOMSVGPathSegList::GetItemAt(uint32_t aIndex) { + MOZ_ASSERT(aIndex < mItems.Length()); + + if (!ItemAt(aIndex)) { + ItemAt(aIndex) = DOMSVGPathSeg::CreateFor(this, aIndex, IsAnimValList()); + } + RefPtr<DOMSVGPathSeg> result = ItemAt(aIndex); + return result.forget(); +} + +void DOMSVGPathSegList::MaybeInsertNullInAnimValListAt( + uint32_t aIndex, uint32_t aInternalIndex, uint32_t aArgCountForItem) { + MOZ_ASSERT(!IsAnimValList(), "call from baseVal to animVal"); + + if (!AnimListMirrorsBaseList()) { + return; + } + + // The anim val list is in sync with the base val list + DOMSVGPathSegList* 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, ItemProxy(nullptr, aInternalIndex), fallible)); + + animVal->UpdateListIndicesFromIndex(aIndex + 1, 1 + aArgCountForItem); +} + +void DOMSVGPathSegList::MaybeRemoveItemFromAnimValListAt( + uint32_t aIndex, int32_t aArgCountForItem) { + 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<DOMSVGPathSegList> 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->ItemAt(aIndex)) { + animVal->ItemAt(aIndex)->RemovingFromList(); + } + animVal->mItems.RemoveElementAt(aIndex); + + animVal->UpdateListIndicesFromIndex(aIndex, -(1 + aArgCountForItem)); +} + +void DOMSVGPathSegList::UpdateListIndicesFromIndex( + uint32_t aStartingIndex, int32_t aInternalDataIndexDelta) { + uint32_t length = mItems.Length(); + + for (uint32_t i = aStartingIndex; i < length; ++i) { + mItems[i].mInternalDataIndex += aInternalDataIndexDelta; + if (ItemAt(i)) { + ItemAt(i)->UpdateListIndex(i); + } + } +} + +} // namespace mozilla::dom |