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/* -*- 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 "mozilla/dom/MutationEventBinding.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(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);
}
}
DocGroup* nsDOMStringMap::GetDocGroup() const {
return mElement ? mElement->GetDocGroup() : nullptr;
}
/* virtual */
JSObject* nsDOMStringMap::WrapObject(JSContext* cx,
JS::Handle<JSObject*> aGivenProto) {
return DOMStringMap_Binding::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;
}
RefPtr<nsAtom> 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;
}
RefPtr<nsAtom> 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, u"data-"_ns)) {
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(Element* aElement, int32_t aNameSpaceID,
nsAtom* aAttribute, int32_t aModType,
const nsAttrValue* aOldValue) {
if ((aModType == MutationEvent_Binding::ADDITION ||
aModType == MutationEvent_Binding::REMOVAL) &&
aNameSpaceID == kNameSpaceID_None &&
StringBeginsWith(nsDependentAtomString(aAttribute), u"data-"_ns)) {
++mExpandoAndGeneration.generation;
}
}