diff options
Diffstat (limited to 'dom/svg/SVGFragmentIdentifier.cpp')
| -rw-r--r-- | dom/svg/SVGFragmentIdentifier.cpp | 202 |
1 files changed, 202 insertions, 0 deletions
diff --git a/dom/svg/SVGFragmentIdentifier.cpp b/dom/svg/SVGFragmentIdentifier.cpp new file mode 100644 index 000000000..3adad5444 --- /dev/null +++ b/dom/svg/SVGFragmentIdentifier.cpp @@ -0,0 +1,202 @@ +/* -*- 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 "SVGFragmentIdentifier.h" + +#include "mozilla/dom/SVGSVGElement.h" +#include "mozilla/dom/SVGViewElement.h" +#include "nsContentUtils.h" // for nsCharSeparatedTokenizerTemplate +#include "nsSVGAnimatedTransformList.h" +#include "nsCharSeparatedTokenizer.h" + +namespace mozilla { + +using namespace dom; + +static bool +IsMatchingParameter(const nsAString& aString, const nsAString& aParameterName) +{ + // The first two tests ensure aString.Length() > aParameterName.Length() + // so it's then safe to do the third test + return StringBeginsWith(aString, aParameterName) && + aString.Last() == ')' && + aString.CharAt(aParameterName.Length()) == '('; +} + +inline bool +IgnoreWhitespace(char16_t aChar) +{ + return false; +} + +static SVGViewElement* +GetViewElement(nsIDocument* aDocument, const nsAString& aId) +{ + Element* element = aDocument->GetElementById(aId); + return (element && element->IsSVGElement(nsGkAtoms::view)) ? + static_cast<SVGViewElement*>(element) : nullptr; +} + +// Handles setting/clearing the root's mSVGView pointer. +class MOZ_RAII AutoSVGViewHandler +{ +public: + explicit AutoSVGViewHandler(SVGSVGElement* aRoot + MOZ_GUARD_OBJECT_NOTIFIER_PARAM) + : mRoot(aRoot), mValid(false) { + MOZ_GUARD_OBJECT_NOTIFIER_INIT; + mWasOverridden = mRoot->UseCurrentView(); + mRoot->mSVGView = nullptr; + mRoot->mCurrentViewID = nullptr; + } + + ~AutoSVGViewHandler() { + if (!mWasOverridden && !mValid) { + // we weren't overridden before and we aren't + // overridden now so nothing has changed. + return; + } + if (mValid) { + mRoot->mSVGView = mSVGView; + } + mRoot->InvalidateTransformNotifyFrame(); + } + + void CreateSVGView() { + MOZ_ASSERT(!mSVGView, "CreateSVGView should not be called multiple times"); + mSVGView = new SVGView(); + } + + bool ProcessAttr(const nsAString& aToken, const nsAString &aParams) { + + MOZ_ASSERT(mSVGView, "CreateSVGView should have been called"); + + // SVGViewAttributes may occur in any order, but each type may only occur + // at most one time in a correctly formed SVGViewSpec. + // If we encounter any attribute more than once or get any syntax errors + // we're going to return false and cancel any changes. + + if (IsMatchingParameter(aToken, NS_LITERAL_STRING("viewBox"))) { + if (mSVGView->mViewBox.IsExplicitlySet() || + NS_FAILED(mSVGView->mViewBox.SetBaseValueString( + aParams, mRoot, false))) { + return false; + } + } else if (IsMatchingParameter(aToken, NS_LITERAL_STRING("preserveAspectRatio"))) { + if (mSVGView->mPreserveAspectRatio.IsExplicitlySet() || + NS_FAILED(mSVGView->mPreserveAspectRatio.SetBaseValueString( + aParams, mRoot, false))) { + return false; + } + } else if (IsMatchingParameter(aToken, NS_LITERAL_STRING("transform"))) { + if (mSVGView->mTransforms) { + return false; + } + mSVGView->mTransforms = new nsSVGAnimatedTransformList(); + if (NS_FAILED(mSVGView->mTransforms->SetBaseValueString(aParams))) { + return false; + } + } else if (IsMatchingParameter(aToken, NS_LITERAL_STRING("zoomAndPan"))) { + if (mSVGView->mZoomAndPan.IsExplicitlySet()) { + return false; + } + nsIAtom* valAtom = NS_GetStaticAtom(aParams); + if (!valAtom || + NS_FAILED(mSVGView->mZoomAndPan.SetBaseValueAtom( + valAtom, mRoot))) { + return false; + } + } else { + // We don't support viewTarget currently + return false; + } + return true; + } + + void SetValid() { + mValid = true; + } + +private: + SVGSVGElement* mRoot; + nsAutoPtr<SVGView> mSVGView; + bool mValid; + bool mWasOverridden; + MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER +}; + +bool +SVGFragmentIdentifier::ProcessSVGViewSpec(const nsAString& aViewSpec, + SVGSVGElement* aRoot) +{ + AutoSVGViewHandler viewHandler(aRoot); + + if (!IsMatchingParameter(aViewSpec, NS_LITERAL_STRING("svgView"))) { + return false; + } + + // Each token is a SVGViewAttribute + int32_t bracketPos = aViewSpec.FindChar('('); + uint32_t lengthOfViewSpec = aViewSpec.Length() - bracketPos - 2; + nsCharSeparatedTokenizerTemplate<IgnoreWhitespace> tokenizer( + Substring(aViewSpec, bracketPos + 1, lengthOfViewSpec), ';'); + + if (!tokenizer.hasMoreTokens()) { + return false; + } + viewHandler.CreateSVGView(); + + do { + + nsAutoString token(tokenizer.nextToken()); + + bracketPos = token.FindChar('('); + if (bracketPos < 1 || token.Last() != ')') { + // invalid SVGViewAttribute syntax + return false; + } + + const nsAString ¶ms = + Substring(token, bracketPos + 1, token.Length() - bracketPos - 2); + + if (!viewHandler.ProcessAttr(token, params)) { + return false; + } + + } while (tokenizer.hasMoreTokens()); + + viewHandler.SetValid(); + return true; +} + +bool +SVGFragmentIdentifier::ProcessFragmentIdentifier(nsIDocument* aDocument, + const nsAString& aAnchorName) +{ + MOZ_ASSERT(aDocument->GetRootElement()->IsSVGElement(nsGkAtoms::svg), + "expecting an SVG root element"); + + SVGSVGElement* rootElement = + static_cast<SVGSVGElement*>(aDocument->GetRootElement()); + + const SVGViewElement* viewElement = GetViewElement(aDocument, aAnchorName); + + if (viewElement) { + if (!rootElement->mCurrentViewID) { + rootElement->mCurrentViewID = new nsString(); + } + *rootElement->mCurrentViewID = aAnchorName; + rootElement->mSVGView = nullptr; + rootElement->InvalidateTransformNotifyFrame(); + // not an svgView()-style fragment identifier, return false so the caller + // continues processing to match any :target pseudo elements + return false; + } + + return ProcessSVGViewSpec(aAnchorName, rootElement); +} + +} // namespace mozilla |