dom/svg/DOMSVGStringList.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "DOMSVGStringList.h"
   8
   9 #include "mozAutoDocUpdate.h"
  10 #include "mozilla/dom/SVGStringListBinding.h"
  11 #include "mozilla/dom/SVGTests.h"
  12 #include "nsCOMPtr.h"
  13 #include "nsError.h"
  14 #include "nsQueryObject.h"
  15 #include "SVGAttrTearoffTable.h"
  16 #include <algorithm>
  17
  18 // See the architecture comment in this file's header.
  19
  20 namespace mozilla::dom {
  21
  22 static inline SVGAttrTearoffTable<SVGStringList, DOMSVGStringList>&
  23 SVGStringListTearoffTable() {
  24   static SVGAttrTearoffTable<SVGStringList, DOMSVGStringList>
  25       sSVGStringListTearoffTable;
  26   return sSVGStringListTearoffTable;
  27 }
  28
  29 NS_IMPL_CYCLE_COLLECTION_CLASS(DOMSVGStringList)
  30
  31 NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(DOMSVGStringList)
  32   // No unlinking of mElement, we'd need to null out the value pointer (the
  33   // object it points to is held by the element) and null-check it everywhere.
  34   tmp->RemoveFromTearoffTable();
  35   NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER
  36 NS_IMPL_CYCLE_COLLECTION_UNLINK_END
  37 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(DOMSVGStringList)
  38   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mElement)
  39 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
  40 NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(DOMSVGStringList)
  41   NS_IMPL_CYCLE_COLLECTION_TRACE_PRESERVED_WRAPPER
  42 NS_IMPL_CYCLE_COLLECTION_TRACE_END
  43
  44 NS_IMPL_CYCLE_COLLECTING_ADDREF(DOMSVGStringList)
  45 NS_IMPL_CYCLE_COLLECTING_RELEASE(DOMSVGStringList)
  46
  47 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(DOMSVGStringList)
  48   NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
  49   NS_INTERFACE_MAP_ENTRY(nsISupports)
  50 NS_INTERFACE_MAP_END
  51
  52 //----------------------------------------------------------------------
  53 // Helper class: AutoChangeStringListNotifier
  54 // Stack-based helper class to pair calls to WillChangeStringListList and
  55 // DidChangeStringListList.
  56 class MOZ_RAII AutoChangeStringListNotifier : public mozAutoDocUpdate {
  57  public:
  58   explicit AutoChangeStringListNotifier(DOMSVGStringList* aStringList)
  59       : mozAutoDocUpdate(aStringList->mElement->GetComposedDoc(), true),
  60         mStringList(aStringList) {
  61     MOZ_ASSERT(mStringList, "Expecting non-null stringList");
  62     mEmptyOrOldValue = mStringList->mElement->WillChangeStringList(
  63         mStringList->mIsConditionalProcessingAttribute, mStringList->mAttrEnum,
  64         *this);
  65   }
  66
  67   ~AutoChangeStringListNotifier() {
  68     mStringList->mElement->DidChangeStringList(
  69         mStringList->mIsConditionalProcessingAttribute, mStringList->mAttrEnum,
  70         mEmptyOrOldValue, *this);
  71   }
  72
  73  private:
  74   DOMSVGStringList* const mStringList;
  75   nsAttrValue mEmptyOrOldValue;
  76 };
  77
  78 /* static */
  79 already_AddRefed<DOMSVGStringList> DOMSVGStringList::GetDOMWrapper(
  80     SVGStringList* aList, SVGElement* aElement,
  81     bool aIsConditionalProcessingAttribute, uint8_t aAttrEnum) {
  82   RefPtr<DOMSVGStringList> wrapper =
  83       SVGStringListTearoffTable().GetTearoff(aList);
  84   if (!wrapper) {
  85     wrapper = new DOMSVGStringList(aElement, aIsConditionalProcessingAttribute,
  86                                    aAttrEnum);
  87     SVGStringListTearoffTable().AddTearoff(aList, wrapper);
  88   }
  89   return wrapper.forget();
  90 }
  91
  92 void DOMSVGStringList::RemoveFromTearoffTable() {
  93   // Script no longer has any references to us.
  94   SVGStringListTearoffTable().RemoveTearoff(&InternalList());
  95 }
  96
  97 DOMSVGStringList::~DOMSVGStringList() { RemoveFromTearoffTable(); }
  98
  99 /* virtual */
 100 JSObject* DOMSVGStringList::WrapObject(JSContext* aCx,
 101                                        JS::Handle<JSObject*> aGivenProto) {
 102   return SVGStringList_Binding::Wrap(aCx, this, aGivenProto);
 103 }
 104
 105 // ----------------------------------------------------------------------------
 106 // SVGStringList implementation:
 107
 108 uint32_t DOMSVGStringList::NumberOfItems() const {
 109   return InternalList().Length();
 110 }
 111
 112 uint32_t DOMSVGStringList::Length() const { return NumberOfItems(); }
 113
 114 void DOMSVGStringList::Clear() {
 115   if (InternalList().IsExplicitlySet()) {
 116     AutoChangeStringListNotifier notifier(this);
 117     InternalList().Clear();
 118   }
 119 }
 120
 121 void DOMSVGStringList::Initialize(const nsAString& aNewItem, nsAString& aRetval,
 122                                   ErrorResult& aRv) {
 123   if (InternalList().IsExplicitlySet()) {
 124     InternalList().Clear();
 125   }
 126   InsertItemBefore(aNewItem, 0, aRetval, aRv);
 127 }
 128
 129 void DOMSVGStringList::GetItem(uint32_t aIndex, nsAString& aRetval,
 130                                ErrorResult& aRv) {
 131   bool found;
 132   IndexedGetter(aIndex, found, aRetval);
 133   if (!found) {
 134     aRv.Throw(NS_ERROR_DOM_INDEX_SIZE_ERR);
 135   }
 136 }
 137
 138 void DOMSVGStringList::IndexedGetter(uint32_t aIndex, bool& aFound,
 139                                      nsAString& aRetval) {
 140   aFound = aIndex < InternalList().Length();
 141   if (aFound) {
 142     aRetval = InternalList()[aIndex];
 143   }
 144 }
 145
 146 void DOMSVGStringList::InsertItemBefore(const nsAString& aNewItem,
 147                                         uint32_t aIndex, nsAString& aRetval,
 148                                         ErrorResult& aRv) {
 149   if (aNewItem.IsEmpty()) {
 150     aRv.Throw(NS_ERROR_DOM_SYNTAX_ERR);
 151     return;
 152   }
 153   aIndex = std::min(aIndex, InternalList().Length());
 154
 155   // Ensure we have enough memory so we can avoid complex error handling below:
 156   if (!InternalList().SetCapacity(InternalList().Length() + 1)) {
 157     aRv.Throw(NS_ERROR_OUT_OF_MEMORY);
 158     return;
 159   }
 160
 161   AutoChangeStringListNotifier notifier(this);
 162   InternalList().InsertItem(aIndex, aNewItem);
 163   aRetval = aNewItem;
 164 }
 165
 166 void DOMSVGStringList::ReplaceItem(const nsAString& aNewItem, uint32_t aIndex,
 167                                    nsAString& aRetval, ErrorResult& aRv) {
 168   if (aNewItem.IsEmpty()) {
 169     aRv.Throw(NS_ERROR_DOM_SYNTAX_ERR);
 170     return;
 171   }
 172   if (aIndex >= InternalList().Length()) {
 173     aRv.Throw(NS_ERROR_DOM_INDEX_SIZE_ERR);
 174     return;
 175   }
 176
 177   aRetval = InternalList()[aIndex];
 178   AutoChangeStringListNotifier notifier(this);
 179   InternalList().ReplaceItem(aIndex, aNewItem);
 180 }
 181
 182 void DOMSVGStringList::RemoveItem(uint32_t aIndex, nsAString& aRetval,
 183                                   ErrorResult& aRv) {
 184   if (aIndex >= InternalList().Length()) {
 185     aRv.Throw(NS_ERROR_DOM_INDEX_SIZE_ERR);
 186     return;
 187   }
 188
 189   AutoChangeStringListNotifier notifier(this);
 190   InternalList().RemoveItem(aIndex);
 191 }
 192
 193 void DOMSVGStringList::AppendItem(const nsAString& aNewItem, nsAString& aRetval,
 194                                   ErrorResult& aRv) {
 195   InsertItemBefore(aNewItem, InternalList().Length(), aRetval, aRv);
 196 }
 197
 198 SVGStringList& DOMSVGStringList::InternalList() const {
 199   if (mIsConditionalProcessingAttribute) {
 200     nsCOMPtr<dom::SVGTests> tests = do_QueryObject(mElement);
 201     return tests->mStringListAttributes[mAttrEnum];
 202   }
 203   return mElement->GetStringListInfo().mValues[mAttrEnum];
 204 }
 205
 206 }  // namespace mozilla::dom