/* -*- 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/. */ /* * Storage of the children and attributes of a DOM node; storage for * the two is unified to minimize footprint. */ #ifndef nsAttrAndChildArray_h___ #define nsAttrAndChildArray_h___ #include "mozilla/Attributes.h" #include "mozilla/MemoryReporting.h" #include "mozilla/dom/BorrowedAttrInfo.h" #include "nscore.h" #include "nsAttrName.h" #include "nsAttrValue.h" #include "nsCaseTreatment.h" class nsINode; class nsIContent; class nsMappedAttributes; class nsHTMLStyleSheet; class nsRuleWalker; class nsMappedAttributeElement; #define ATTRCHILD_ARRAY_GROWSIZE 8 #define ATTRCHILD_ARRAY_LINEAR_THRESHOLD 32 #define ATTRCHILD_ARRAY_ATTR_SLOTS_BITS 10 #define ATTRCHILD_ARRAY_MAX_ATTR_COUNT \ ((1 << ATTRCHILD_ARRAY_ATTR_SLOTS_BITS) - 1) #define ATTRCHILD_ARRAY_MAX_CHILD_COUNT \ (~uint32_t(0) >> ATTRCHILD_ARRAY_ATTR_SLOTS_BITS) #define ATTRCHILD_ARRAY_ATTR_SLOTS_COUNT_MASK \ ((1 << ATTRCHILD_ARRAY_ATTR_SLOTS_BITS) - 1) #define ATTRSIZE (sizeof(InternalAttr) / sizeof(void*)) class nsAttrAndChildArray { typedef mozilla::dom::BorrowedAttrInfo BorrowedAttrInfo; public: nsAttrAndChildArray(); ~nsAttrAndChildArray(); uint32_t ChildCount() const { return mImpl ? (mImpl->mAttrAndChildCount >> ATTRCHILD_ARRAY_ATTR_SLOTS_BITS) : 0; } nsIContent* ChildAt(uint32_t aPos) const { NS_ASSERTION(aPos < ChildCount(), "out-of-bounds access in nsAttrAndChildArray"); return reinterpret_cast<nsIContent*>(mImpl->mBuffer[AttrSlotsSize() + aPos]); } nsIContent* GetSafeChildAt(uint32_t aPos) const; nsIContent * const * GetChildArray(uint32_t* aChildCount) const; nsresult AppendChild(nsIContent* aChild) { return InsertChildAt(aChild, ChildCount()); } nsresult InsertChildAt(nsIContent* aChild, uint32_t aPos); void RemoveChildAt(uint32_t aPos); // Like RemoveChildAt but hands the reference to the child being // removed back to the caller instead of just releasing it. already_AddRefed<nsIContent> TakeChildAt(uint32_t aPos); int32_t IndexOfChild(const nsINode* aPossibleChild) const; bool HasAttrs() const { return MappedAttrCount() || (AttrSlotCount() && AttrSlotIsTaken(0)); } uint32_t AttrCount() const; const nsAttrValue* GetAttr(nsIAtom* aLocalName, int32_t aNamespaceID = kNameSpaceID_None) const; // As above but using a string attr name and always using // kNameSpaceID_None. This is always case-sensitive. const nsAttrValue* GetAttr(const nsAString& aName) const; // Get an nsAttrValue by qualified name. Can optionally do // ASCII-case-insensitive name matching. const nsAttrValue* GetAttr(const nsAString& aName, nsCaseTreatment aCaseSensitive) const; const nsAttrValue* AttrAt(uint32_t aPos) const; // SetAndSwapAttr swaps the current attribute value with aValue. nsresult SetAndSwapAttr(nsIAtom* aLocalName, nsAttrValue& aValue); nsresult SetAndSwapAttr(mozilla::dom::NodeInfo* aName, nsAttrValue& aValue); // Remove the attr at position aPos. The value of the attr is placed in // aValue; any value that was already in aValue is destroyed. nsresult RemoveAttrAt(uint32_t aPos, nsAttrValue& aValue); // Returns attribute name at given position, *not* out-of-bounds safe const nsAttrName* AttrNameAt(uint32_t aPos) const; // Returns the attribute info at a given position, *not* out-of-bounds safe BorrowedAttrInfo AttrInfoAt(uint32_t aPos) const; // Returns attribute name at given position or null if aPos is out-of-bounds const nsAttrName* GetSafeAttrNameAt(uint32_t aPos) const; const nsAttrName* GetExistingAttrNameFromQName(const nsAString& aName) const; int32_t IndexOfAttr(nsIAtom* aLocalName, int32_t aNamespaceID = kNameSpaceID_None) const; nsresult SetAndTakeMappedAttr(nsIAtom* aLocalName, nsAttrValue& aValue, nsMappedAttributeElement* aContent, nsHTMLStyleSheet* aSheet); nsresult SetMappedAttrStyleSheet(nsHTMLStyleSheet* aSheet) { if (!mImpl || !mImpl->mMappedAttrs) { return NS_OK; } return DoSetMappedAttrStyleSheet(aSheet); } void WalkMappedAttributeStyleRules(nsRuleWalker* aRuleWalker); void Compact(); bool CanFitMoreAttrs() const { return AttrSlotCount() < ATTRCHILD_ARRAY_MAX_ATTR_COUNT || !AttrSlotIsTaken(ATTRCHILD_ARRAY_MAX_ATTR_COUNT - 1); } size_t SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const; bool HasMappedAttrs() const { return MappedAttrCount(); } private: nsAttrAndChildArray(const nsAttrAndChildArray& aOther) = delete; nsAttrAndChildArray& operator=(const nsAttrAndChildArray& aOther) = delete; void Clear(); uint32_t NonMappedAttrCount() const; uint32_t MappedAttrCount() const; // Returns a non-null zero-refcount object. nsMappedAttributes* GetModifiableMapped(nsMappedAttributeElement* aContent, nsHTMLStyleSheet* aSheet, bool aWillAddAttr); nsresult MakeMappedUnique(nsMappedAttributes* aAttributes); uint32_t AttrSlotsSize() const { return AttrSlotCount() * ATTRSIZE; } uint32_t AttrSlotCount() const { return mImpl ? mImpl->mAttrAndChildCount & ATTRCHILD_ARRAY_ATTR_SLOTS_COUNT_MASK : 0; } bool AttrSlotIsTaken(uint32_t aSlot) const { NS_PRECONDITION(aSlot < AttrSlotCount(), "out-of-bounds"); return mImpl->mBuffer[aSlot * ATTRSIZE]; } void SetChildCount(uint32_t aCount) { mImpl->mAttrAndChildCount = (mImpl->mAttrAndChildCount & ATTRCHILD_ARRAY_ATTR_SLOTS_COUNT_MASK) | (aCount << ATTRCHILD_ARRAY_ATTR_SLOTS_BITS); } void SetAttrSlotCount(uint32_t aCount) { mImpl->mAttrAndChildCount = (mImpl->mAttrAndChildCount & ~ATTRCHILD_ARRAY_ATTR_SLOTS_COUNT_MASK) | aCount; } void SetAttrSlotAndChildCount(uint32_t aSlotCount, uint32_t aChildCount) { mImpl->mAttrAndChildCount = aSlotCount | (aChildCount << ATTRCHILD_ARRAY_ATTR_SLOTS_BITS); } bool GrowBy(uint32_t aGrowSize); bool AddAttrSlot(); /** * Set *aPos to aChild and update sibling pointers as needed. aIndex is the * index at which aChild is actually being inserted. aChildCount is the * number of kids we had before the insertion. */ inline void SetChildAtPos(void** aPos, nsIContent* aChild, uint32_t aIndex, uint32_t aChildCount); /** * Guts of SetMappedAttrStyleSheet for the rare case when we have mapped attrs */ nsresult DoSetMappedAttrStyleSheet(nsHTMLStyleSheet* aSheet); struct InternalAttr { nsAttrName mName; nsAttrValue mValue; }; struct Impl { uint32_t mAttrAndChildCount; uint32_t mBufferSize; nsMappedAttributes* mMappedAttrs; void* mBuffer[1]; }; Impl* mImpl; }; #endif