/* -*- 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 "nsDOMStringMap.h" #include "jsapi.h" #include "nsError.h" #include "nsGenericHTMLElement.h" #include "nsContentUtils.h" #include "mozilla/dom/DOMStringMapBinding.h" #include "nsIDOMMutationEvent.h" using namespace mozilla; using namespace mozilla::dom; NS_IMPL_CYCLE_COLLECTION_CLASS(nsDOMStringMap) NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(nsDOMStringMap) NS_IMPL_CYCLE_COLLECTION_TRAVERSE_SCRIPT_OBJECTS NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mElement) NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(nsDOMStringMap) NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER // Check that mElement exists in case the unlink code is run more than once. if (tmp->mElement) { // Call back to element to null out weak reference to this object. tmp->mElement->ClearDataset(); tmp->mElement->RemoveMutationObserver(tmp); tmp->mElement = nullptr; } tmp->mExpandoAndGeneration.OwnerUnlinked(); NS_IMPL_CYCLE_COLLECTION_UNLINK_END NS_IMPL_CYCLE_COLLECTION_TRACE_WRAPPERCACHE(nsDOMStringMap) NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(nsDOMStringMap) NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY NS_INTERFACE_MAP_ENTRY(nsIMutationObserver) NS_INTERFACE_MAP_ENTRY(nsISupports) NS_INTERFACE_MAP_END NS_IMPL_CYCLE_COLLECTING_ADDREF(nsDOMStringMap) NS_IMPL_CYCLE_COLLECTING_RELEASE(nsDOMStringMap) nsDOMStringMap::nsDOMStringMap(Element* aElement) : mElement(aElement), mRemovingProp(false) { mElement->AddMutationObserver(this); } nsDOMStringMap::~nsDOMStringMap() { // Check if element still exists, may have been unlinked by cycle collector. if (mElement) { // Call back to element to null out weak reference to this object. mElement->ClearDataset(); mElement->RemoveMutationObserver(this); } } /* virtual */ JSObject* nsDOMStringMap::WrapObject(JSContext *cx, JS::Handle<JSObject*> aGivenProto) { return DOMStringMapBinding::Wrap(cx, this, aGivenProto); } void nsDOMStringMap::NamedGetter(const nsAString& aProp, bool& found, DOMString& aResult) const { nsAutoString attr; if (!DataPropToAttr(aProp, attr)) { found = false; return; } found = mElement->GetAttr(attr, aResult); } void nsDOMStringMap::NamedSetter(const nsAString& aProp, const nsAString& aValue, ErrorResult& rv) { nsAutoString attr; if (!DataPropToAttr(aProp, attr)) { rv.Throw(NS_ERROR_DOM_SYNTAX_ERR); return; } nsresult res = nsContentUtils::CheckQName(attr, false); if (NS_FAILED(res)) { rv.Throw(res); return; } nsCOMPtr<nsIAtom> attrAtom = NS_Atomize(attr); MOZ_ASSERT(attrAtom, "Should be infallible"); res = mElement->SetAttr(kNameSpaceID_None, attrAtom, aValue, true); if (NS_FAILED(res)) { rv.Throw(res); } } void nsDOMStringMap::NamedDeleter(const nsAString& aProp, bool& found) { // Currently removing property, attribute is already removed. if (mRemovingProp) { found = false; return; } nsAutoString attr; if (!DataPropToAttr(aProp, attr)) { found = false; return; } nsCOMPtr<nsIAtom> attrAtom = NS_Atomize(attr); MOZ_ASSERT(attrAtom, "Should be infallible"); found = mElement->HasAttr(kNameSpaceID_None, attrAtom); if (found) { mRemovingProp = true; mElement->UnsetAttr(kNameSpaceID_None, attrAtom, true); mRemovingProp = false; } } void nsDOMStringMap::GetSupportedNames(nsTArray<nsString>& aNames) { uint32_t attrCount = mElement->GetAttrCount(); // Iterate through all the attributes and add property // names corresponding to data attributes to return array. for (uint32_t i = 0; i < attrCount; ++i) { const nsAttrName* attrName = mElement->GetAttrNameAt(i); // Skip the ones that are not in the null namespace if (attrName->NamespaceID() != kNameSpaceID_None) { continue; } nsAutoString prop; if (!AttrToDataProp(nsDependentAtomString(attrName->LocalName()), prop)) { continue; } aNames.AppendElement(prop); } } /** * Converts a dataset property name to the corresponding data attribute name. * (ex. aBigFish to data-a-big-fish). */ bool nsDOMStringMap::DataPropToAttr(const nsAString& aProp, nsAutoString& aResult) { // aResult is an autostring, so don't worry about setting its capacity: // SetCapacity is slow even when it's a no-op and we already have enough // storage there for most cases, probably. aResult.AppendLiteral("data-"); // Iterate property by character to form attribute name. // Return syntax error if there is a sequence of "-" followed by a character // in the range "a" to "z". // Replace capital characters with "-" followed by lower case character. // Otherwise, simply append character to attribute name. const char16_t* start = aProp.BeginReading(); const char16_t* end = aProp.EndReading(); const char16_t* cur = start; for (; cur < end; ++cur) { const char16_t* next = cur + 1; if (char16_t('-') == *cur && next < end && char16_t('a') <= *next && *next <= char16_t('z')) { // Syntax error if character following "-" is in range "a" to "z". return false; } if (char16_t('A') <= *cur && *cur <= char16_t('Z')) { // Append the characters in the range [start, cur) aResult.Append(start, cur - start); // Uncamel-case characters in the range of "A" to "Z". aResult.Append(char16_t('-')); aResult.Append(*cur - 'A' + 'a'); start = next; // We've already appended the thing at *cur } } aResult.Append(start, cur - start); return true; } /** * Converts a data attribute name to the corresponding dataset property name. * (ex. data-a-big-fish to aBigFish). */ bool nsDOMStringMap::AttrToDataProp(const nsAString& aAttr, nsAutoString& aResult) { // If the attribute name does not begin with "data-" then it can not be // a data attribute. if (!StringBeginsWith(aAttr, NS_LITERAL_STRING("data-"))) { return false; } // Start reading attribute from first character after "data-". const char16_t* cur = aAttr.BeginReading() + 5; const char16_t* end = aAttr.EndReading(); // Don't try to mess with aResult's capacity: the probably-no-op SetCapacity() // call is not that fast. // Iterate through attrName by character to form property name. // If there is a sequence of "-" followed by a character in the range "a" to // "z" then replace with upper case letter. // Otherwise append character to property name. for (; cur < end; ++cur) { const char16_t* next = cur + 1; if (char16_t('-') == *cur && next < end && char16_t('a') <= *next && *next <= char16_t('z')) { // Upper case the lower case letters that follow a "-". aResult.Append(*next - 'a' + 'A'); // Consume character to account for "-" character. ++cur; } else { // Simply append character if camel case is not necessary. aResult.Append(*cur); } } return true; } void nsDOMStringMap::AttributeChanged(nsIDocument *aDocument, Element* aElement, int32_t aNameSpaceID, nsIAtom* aAttribute, int32_t aModType, const nsAttrValue* aOldValue) { if ((aModType == nsIDOMMutationEvent::ADDITION || aModType == nsIDOMMutationEvent::REMOVAL) && aNameSpaceID == kNameSpaceID_None && StringBeginsWith(nsDependentAtomString(aAttribute), NS_LITERAL_STRING("data-"))) { ++mExpandoAndGeneration.generation; } }