/* -*- 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 MOZILLA_SVGNUMBERLIST_H__ #define MOZILLA_SVGNUMBERLIST_H__ #include "nsCOMPtr.h" #include "nsDebug.h" #include "nsIContent.h" #include "nsINode.h" #include "nsIWeakReferenceUtils.h" #include "nsSVGElement.h" #include "nsTArray.h" namespace mozilla { /** * ATTENTION! WARNING! WATCH OUT!! * * Consumers that modify objects of this type absolutely MUST keep the DOM * wrappers for those lists (if any) in sync!! That's why this class is so * locked down. * * The DOM wrapper class for this class is DOMSVGNumberList. */ class SVGNumberList { friend class SVGAnimatedNumberList; friend class DOMSVGNumberList; friend class DOMSVGNumber; public: SVGNumberList(){} ~SVGNumberList(){} // Only methods that don't make/permit modification to this list are public. // Only our friend classes can access methods that may change us. /// This may return an incomplete string on OOM, but that's acceptable. void GetValueAsString(nsAString& aValue) const; bool IsEmpty() const { return mNumbers.IsEmpty(); } uint32_t Length() const { return mNumbers.Length(); } const float& operator[](uint32_t aIndex) const { return mNumbers[aIndex]; } bool operator==(const SVGNumberList& rhs) const { return mNumbers == rhs.mNumbers; } bool SetCapacity(uint32_t size) { return mNumbers.SetCapacity(size, fallible); } void Compact() { mNumbers.Compact(); } // Access to methods that can modify objects of this type is deliberately // limited. This is to reduce the chances of someone modifying objects of // this type without taking the necessary steps to keep DOM wrappers in sync. // If you need wider access to these methods, consider adding a method to // SVGAnimatedNumberList and having that class act as an intermediary so it // can take care of keeping DOM wrappers in sync. protected: /** * This may fail on OOM if the internal capacity needs to be increased, in * which case the list will be left unmodified. */ nsresult CopyFrom(const SVGNumberList& rhs); float& operator[](uint32_t aIndex) { return mNumbers[aIndex]; } /** * This may fail (return false) on OOM if the internal capacity is being * increased, in which case the list will be left unmodified. */ bool SetLength(uint32_t aNumberOfItems) { return mNumbers.SetLength(aNumberOfItems, fallible); } private: // Marking the following private only serves to show which methods are only // used by our friend classes (as opposed to our subclasses) - it doesn't // really provide additional safety. nsresult SetValueFromString(const nsAString& aValue); void Clear() { mNumbers.Clear(); } bool InsertItem(uint32_t aIndex, const float &aNumber) { if (aIndex >= mNumbers.Length()) { aIndex = mNumbers.Length(); } return !!mNumbers.InsertElementAt(aIndex, aNumber, fallible); } void ReplaceItem(uint32_t aIndex, const float &aNumber) { MOZ_ASSERT(aIndex < mNumbers.Length(), "DOM wrapper caller should have raised INDEX_SIZE_ERR"); mNumbers[aIndex] = aNumber; } void RemoveItem(uint32_t aIndex) { MOZ_ASSERT(aIndex < mNumbers.Length(), "DOM wrapper caller should have raised INDEX_SIZE_ERR"); mNumbers.RemoveElementAt(aIndex); } bool AppendItem(float aNumber) { return !!mNumbers.AppendElement(aNumber, fallible); } protected: /* See SVGLengthList for the rationale for using FallibleTArray<float> instead * of FallibleTArray<float, 1>. */ FallibleTArray<float> mNumbers; }; /** * This SVGNumberList subclass is used by the SMIL code when a number list * is to be stored in an nsISMILValue instance. Since nsISMILValue objects may * be cached, it is necessary for us to hold a strong reference to our element * so that it doesn't disappear out from under us if, say, the element is * removed from the DOM tree. */ class SVGNumberListAndInfo : public SVGNumberList { public: SVGNumberListAndInfo() : mElement(nullptr) {} explicit SVGNumberListAndInfo(nsSVGElement *aElement) : mElement(do_GetWeakReference(static_cast<nsINode*>(aElement))) {} void SetInfo(nsSVGElement *aElement) { mElement = do_GetWeakReference(static_cast<nsINode*>(aElement)); } nsSVGElement* Element() const { nsCOMPtr<nsIContent> e = do_QueryReferent(mElement); return static_cast<nsSVGElement*>(e.get()); } nsresult CopyFrom(const SVGNumberListAndInfo& rhs) { mElement = rhs.mElement; return SVGNumberList::CopyFrom(rhs); } // Instances of this special subclass do not have DOM wrappers that we need // to worry about keeping in sync, so it's safe to expose any hidden base // class methods required by the SMIL code, as we do below. /** * Exposed so that SVGNumberList baseVals can be copied to * SVGNumberListAndInfo objects. Note that callers should also call * SetInfo() when using this method! */ nsresult CopyFrom(const SVGNumberList& rhs) { return SVGNumberList::CopyFrom(rhs); } const float& operator[](uint32_t aIndex) const { return SVGNumberList::operator[](aIndex); } float& operator[](uint32_t aIndex) { return SVGNumberList::operator[](aIndex); } bool SetLength(uint32_t aNumberOfItems) { return SVGNumberList::SetLength(aNumberOfItems); } private: // We must keep a weak reference to our element because we may belong to a // cached baseVal nsSMILValue. See the comments starting at: // https://bugzilla.mozilla.org/show_bug.cgi?id=515116#c15 // See also https://bugzilla.mozilla.org/show_bug.cgi?id=653497 nsWeakPtr mElement; }; } // namespace mozilla #endif // MOZILLA_SVGNUMBERLIST_H__