diff options
Diffstat (limited to '')
-rw-r--r-- | dom/svg/DOMSVGNumber.h | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/dom/svg/DOMSVGNumber.h b/dom/svg/DOMSVGNumber.h new file mode 100644 index 0000000000..7023f6bf0f --- /dev/null +++ b/dom/svg/DOMSVGNumber.h @@ -0,0 +1,172 @@ +/* -*- 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/. */ + +#ifndef DOM_SVG_DOMSVGNUMBER_H_ +#define DOM_SVG_DOMSVGNUMBER_H_ + +#include "DOMSVGNumberList.h" +#include "nsCOMPtr.h" +#include "nsCycleCollectionParticipant.h" +#include "nsTArray.h" +#include "mozilla/Attributes.h" +#include "mozilla/RefPtr.h" +#include "nsWrapperCache.h" + +#define MOZ_SVG_LIST_INDEX_BIT_COUNT 27 // supports > 134 million list items + +namespace mozilla { +class ErrorResult; + +namespace dom { +class SVGElement; +class SVGSVGElement; + +/** + * Class DOMSVGNumber + * + * This class creates the DOM objects that wrap internal SVGNumber objects that + * are in an SVGNumberList. It is also used to create the objects returned by + * SVGSVGElement.createSVGNumber(). + * + * For the DOM wrapper classes for non-list SVGNumber, see SVGAnimatedNumber.h. + * + * See the architecture comment in DOMSVGAnimatedNumberList.h. + * + * See the comment in DOMSVGLength.h (yes, LENGTH), which applies here too. + */ +class DOMSVGNumber final : public nsWrapperCache { + template <class T> + friend class AutoChangeNumberListNotifier; + + ~DOMSVGNumber() { + // Our mList's weak ref to us must be nulled out when we die. If GC has + // unlinked us using the cycle collector code, then that has already + // happened, and mList is null. + if (mList) { + mList->mItems[mListIndex] = nullptr; + } + } + + public: + NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(DOMSVGNumber) + NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_NATIVE_CLASS(DOMSVGNumber) + + /** + * Generic ctor for DOMSVGNumber objects that are created for an attribute. + */ + DOMSVGNumber(DOMSVGNumberList* aList, uint8_t aAttrEnum, uint32_t aListIndex, + bool aIsAnimValItem); + + /** + * Ctor for creating the objects returned by SVGSVGElement.createSVGNumber(), + * which do not initially belong to an attribute. + */ + explicit DOMSVGNumber(SVGSVGElement* aParent); + + private: + explicit DOMSVGNumber(nsISupports* aParent); + + public: + /** + * Create an unowned copy. The caller is responsible for the first AddRef(). + */ + DOMSVGNumber* Clone() { + DOMSVGNumber* clone = new DOMSVGNumber(mParent); + clone->mValue = ToSVGNumber(); + return clone; + } + + bool IsInList() const { return !!mList; } + + /** + * Returns true if our attribute is animating. + */ + bool IsAnimating() const { return mList && mList->IsAnimating(); } + + /** + * In future, if this class is used for non-list numbers, this will be + * different to IsInList(). + */ + bool HasOwner() const { return !!mList; } + + /** + * This method is called to notify this DOM object that it is being inserted + * into a list, and give it the information it needs as a result. + * + * This object MUST NOT already belong to a list when this method is called. + * That's not to say that script can't move these DOM objects between + * lists - it can - it's just that the logic to handle that (and send out + * the necessary notifications) is located elsewhere (in DOMSVGNumberList).) + */ + void InsertingIntoList(DOMSVGNumberList* aList, uint8_t aAttrEnum, + uint32_t aListIndex, bool aIsAnimValItem); + + static uint32_t MaxListIndex() { + return (1U << MOZ_SVG_LIST_INDEX_BIT_COUNT) - 1; + } + + /// This method is called to notify this object that its list index changed. + void UpdateListIndex(uint32_t aListIndex) { mListIndex = aListIndex; } + + /** + * This method is called to notify this DOM object that it is about to be + * removed from its current DOM list so that it can first make a copy of its + * internal counterpart's value. (If it didn't do this, then it would + * "lose" its value on being removed.) + */ + void RemovingFromList(); + + float ToSVGNumber(); + + nsISupports* GetParentObject() { return mParent; } + + JSObject* WrapObject(JSContext* aCx, + JS::Handle<JSObject*> aGivenProto) override; + + float Value(); + + void SetValue(float aValue, ErrorResult& aRv); + + private: + dom::SVGElement* Element() { return mList->Element(); } + + uint8_t AttrEnum() const { return mAttrEnum; } + + /** + * Get a reference to the internal SVGNumber list item that this DOM wrapper + * object currently wraps. + * + * To simplify the code we just have this one method for obtaining both + * baseVal and animVal internal items. This means that animVal items don't + * get const protection, but then our setter methods guard against changing + * animVal items. + */ + float& InternalItem(); + +#ifdef DEBUG + bool IndexIsValid(); +#endif + + RefPtr<DOMSVGNumberList> mList; + nsCOMPtr<nsISupports> mParent; + + // Bounds for the following are checked in the ctor, so be sure to update + // that if you change the capacity of any of the following. + + uint32_t mListIndex : MOZ_SVG_LIST_INDEX_BIT_COUNT; + uint32_t mAttrEnum : 4; // supports up to 16 attributes + uint32_t mIsAnimValItem : 1; + + // The following member is only used when we're not in a list: + float mValue; +}; + +} // namespace dom +} // namespace mozilla + +#undef MOZ_SVG_LIST_INDEX_BIT_COUNT + +#endif // DOM_SVG_DOMSVGNUMBER_H_ |