dom/svg/DOMSVGNumber.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 "DOMSVGNumber.h"
   8 #include "DOMSVGNumberList.h"
   9 #include "DOMSVGAnimatedNumberList.h"
  10 #include "SVGAnimatedNumberList.h"
  11 #include "SVGElement.h"
  12 #include "nsError.h"
  13 #include "nsContentUtils.h"  // for NS_ENSURE_FINITE
  14 #include "mozilla/dom/SVGNumberBinding.h"
  15 #include "mozilla/dom/SVGSVGElement.h"
  16
  17 // See the architecture comment in DOMSVGAnimatedNumberList.h.
  18
  19 namespace mozilla::dom {
  20
  21 // We could use NS_IMPL_CYCLE_COLLECTION(, except that in Unlink() we need to
  22 // clear our list's weak ref to us to be safe. (The other option would be to
  23 // not unlink and rely on the breaking of the other edges in the cycle, as
  24 // NS_SVG_VAL_IMPL_CYCLE_COLLECTION does.)
  25 NS_IMPL_CYCLE_COLLECTION_CLASS(DOMSVGNumber)
  26
  27 NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(DOMSVGNumber)
  28   // We may not belong to a list, so we must null check tmp->mList.
  29   if (tmp->mList) {
  30     tmp->mList->mItems[tmp->mListIndex] = nullptr;
  31   }
  32   NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER
  33   NS_IMPL_CYCLE_COLLECTION_UNLINK(mList)
  34   NS_IMPL_CYCLE_COLLECTION_UNLINK(mParent)
  35 NS_IMPL_CYCLE_COLLECTION_UNLINK_END
  36 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(DOMSVGNumber)
  37   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mList)
  38   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mParent)
  39 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
  40 NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(DOMSVGNumber)
  41   NS_IMPL_CYCLE_COLLECTION_TRACE_PRESERVED_WRAPPER
  42 NS_IMPL_CYCLE_COLLECTION_TRACE_END
  43
  44 DOMSVGNumber::DOMSVGNumber(DOMSVGNumberList* aList, uint8_t aAttrEnum,
  45                            uint32_t aListIndex, bool aIsAnimValItem)
  46     : mList(aList),
  47       mParent(aList),
  48       mListIndex(aListIndex),
  49       mAttrEnum(aAttrEnum),
  50       mIsAnimValItem(aIsAnimValItem),
  51       mValue(0.0f) {
  52   // These shifts are in sync with the members in the header.
  53   MOZ_ASSERT(aList && aAttrEnum < (1 << 4) && aListIndex <= MaxListIndex(),
  54              "bad arg");
  55
  56   MOZ_ASSERT(IndexIsValid(), "Bad index for DOMSVGNumber!");
  57 }
  58
  59 DOMSVGNumber::DOMSVGNumber(nsISupports* aParent)
  60     : mList(nullptr),
  61       mParent(aParent),
  62       mListIndex(0),
  63       mAttrEnum(0),
  64       mIsAnimValItem(false),
  65       mValue(0.0f) {}
  66
  67 DOMSVGNumber::DOMSVGNumber(SVGSVGElement* aParent)
  68     : mList(nullptr),
  69       mParent(ToSupports(aParent)),
  70       mListIndex(0),
  71       mAttrEnum(0),
  72       mIsAnimValItem(false),
  73       mValue(0.0f) {}
  74
  75 float DOMSVGNumber::Value() {
  76   if (mIsAnimValItem && HasOwner()) {
  77     Element()->FlushAnimations();  // May make HasOwner() == false
  78   }
  79   return HasOwner() ? InternalItem() : mValue;
  80 }
  81
  82 void DOMSVGNumber::SetValue(float aValue, ErrorResult& aRv) {
  83   if (mIsAnimValItem) {
  84     aRv.Throw(NS_ERROR_DOM_NO_MODIFICATION_ALLOWED_ERR);
  85     return;
  86   }
  87
  88   if (HasOwner()) {
  89     if (InternalItem() == aValue) {
  90       return;
  91     }
  92     AutoChangeNumberListNotifier notifier(this);
  93     InternalItem() = aValue;
  94     return;
  95   }
  96
  97   mValue = aValue;
  98 }
  99
 100 void DOMSVGNumber::InsertingIntoList(DOMSVGNumberList* aList, uint8_t aAttrEnum,
 101                                      uint32_t aListIndex, bool aIsAnimValItem) {
 102   NS_ASSERTION(!HasOwner(), "Inserting item that is already in a list");
 103
 104   mList = aList;
 105   mAttrEnum = aAttrEnum;
 106   mListIndex = aListIndex;
 107   mIsAnimValItem = aIsAnimValItem;
 108
 109   MOZ_ASSERT(IndexIsValid(), "Bad index for DOMSVGNumber!");
 110 }
 111
 112 void DOMSVGNumber::RemovingFromList() {
 113   mValue = InternalItem();
 114   mList = nullptr;
 115   mIsAnimValItem = false;
 116 }
 117
 118 float DOMSVGNumber::ToSVGNumber() {
 119   return HasOwner() ? InternalItem() : mValue;
 120 }
 121
 122 float& DOMSVGNumber::InternalItem() {
 123   SVGAnimatedNumberList* alist = Element()->GetAnimatedNumberList(mAttrEnum);
 124   return mIsAnimValItem && alist->mAnimVal ? (*alist->mAnimVal)[mListIndex]
 125                                            : alist->mBaseVal[mListIndex];
 126 }
 127
 128 #ifdef DEBUG
 129 bool DOMSVGNumber::IndexIsValid() {
 130   SVGAnimatedNumberList* alist = Element()->GetAnimatedNumberList(mAttrEnum);
 131   return (mIsAnimValItem && mListIndex < alist->GetAnimValue().Length()) ||
 132          (!mIsAnimValItem && mListIndex < alist->GetBaseValue().Length());
 133 }
 134 #endif
 135
 136 JSObject* DOMSVGNumber::WrapObject(JSContext* aCx,
 137                                    JS::Handle<JSObject*> aGivenProto) {
 138   return SVGNumber_Binding::Wrap(aCx, this, aGivenProto);
 139 }
 140
 141 }  // namespace mozilla::dom