michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: /*
michael@0:  * Storage of the children and attributes of a DOM node; storage for
michael@0:  * the two is unified to minimize footprint.
michael@0:  */
michael@0: 
michael@0: #ifndef nsAttrAndChildArray_h___
michael@0: #define nsAttrAndChildArray_h___
michael@0: 
michael@0: #include "mozilla/Attributes.h"
michael@0: #include "mozilla/MemoryReporting.h"
michael@0: 
michael@0: #include "nscore.h"
michael@0: #include "nsAttrName.h"
michael@0: #include "nsAttrValue.h"
michael@0: #include "nsCaseTreatment.h"
michael@0: 
michael@0: class nsINode;
michael@0: class nsIContent;
michael@0: class nsMappedAttributes;
michael@0: class nsHTMLStyleSheet;
michael@0: class nsRuleWalker;
michael@0: class nsMappedAttributeElement;
michael@0: 
michael@0: #define ATTRCHILD_ARRAY_GROWSIZE 8
michael@0: #define ATTRCHILD_ARRAY_LINEAR_THRESHOLD 32
michael@0: 
michael@0: #define ATTRCHILD_ARRAY_ATTR_SLOTS_BITS 10
michael@0: 
michael@0: #define ATTRCHILD_ARRAY_MAX_ATTR_COUNT \
michael@0:     ((1 << ATTRCHILD_ARRAY_ATTR_SLOTS_BITS) - 1)
michael@0: 
michael@0: #define ATTRCHILD_ARRAY_MAX_CHILD_COUNT \
michael@0:     (~uint32_t(0) >> ATTRCHILD_ARRAY_ATTR_SLOTS_BITS)
michael@0: 
michael@0: #define ATTRCHILD_ARRAY_ATTR_SLOTS_COUNT_MASK \
michael@0:     ((1 << ATTRCHILD_ARRAY_ATTR_SLOTS_BITS) - 1)
michael@0: 
michael@0: 
michael@0: #define ATTRSIZE (sizeof(InternalAttr) / sizeof(void*))
michael@0: 
michael@0: class nsAttrAndChildArray
michael@0: {
michael@0: public:
michael@0:   nsAttrAndChildArray();
michael@0:   ~nsAttrAndChildArray();
michael@0: 
michael@0:   uint32_t ChildCount() const
michael@0:   {
michael@0:     return mImpl ? (mImpl->mAttrAndChildCount >> ATTRCHILD_ARRAY_ATTR_SLOTS_BITS) : 0;
michael@0:   }
michael@0:   nsIContent* ChildAt(uint32_t aPos) const
michael@0:   {
michael@0:     NS_ASSERTION(aPos < ChildCount(), "out-of-bounds access in nsAttrAndChildArray");
michael@0:     return reinterpret_cast<nsIContent*>(mImpl->mBuffer[AttrSlotsSize() + aPos]);
michael@0:   }
michael@0:   nsIContent* GetSafeChildAt(uint32_t aPos) const;
michael@0:   nsIContent * const * GetChildArray(uint32_t* aChildCount) const;
michael@0:   nsresult AppendChild(nsIContent* aChild)
michael@0:   {
michael@0:     return InsertChildAt(aChild, ChildCount());
michael@0:   }
michael@0:   nsresult InsertChildAt(nsIContent* aChild, uint32_t aPos);
michael@0:   void RemoveChildAt(uint32_t aPos);
michael@0:   // Like RemoveChildAt but hands the reference to the child being
michael@0:   // removed back to the caller instead of just releasing it.
michael@0:   already_AddRefed<nsIContent> TakeChildAt(uint32_t aPos);
michael@0:   int32_t IndexOfChild(const nsINode* aPossibleChild) const;
michael@0: 
michael@0:   bool HasAttrs() const
michael@0:   {
michael@0:     return MappedAttrCount() || (AttrSlotCount() && AttrSlotIsTaken(0));
michael@0:   }
michael@0: 
michael@0:   uint32_t AttrCount() const;
michael@0:   const nsAttrValue* GetAttr(nsIAtom* aLocalName,
michael@0:                              int32_t aNamespaceID = kNameSpaceID_None) const;
michael@0:   // As above but using a string attr name and always using
michael@0:   // kNameSpaceID_None.  This is always case-sensitive.
michael@0:   const nsAttrValue* GetAttr(const nsAString& aName) const;
michael@0:   // Get an nsAttrValue by qualified name.  Can optionally do
michael@0:   // ASCII-case-insensitive name matching.
michael@0:   const nsAttrValue* GetAttr(const nsAString& aName,
michael@0:                              nsCaseTreatment aCaseSensitive) const;
michael@0:   const nsAttrValue* AttrAt(uint32_t aPos) const;
michael@0:   nsresult SetAndTakeAttr(nsIAtom* aLocalName, nsAttrValue& aValue);
michael@0:   nsresult SetAndTakeAttr(nsINodeInfo* aName, nsAttrValue& aValue);
michael@0: 
michael@0:   // Remove the attr at position aPos.  The value of the attr is placed in
michael@0:   // aValue; any value that was already in aValue is destroyed.
michael@0:   nsresult RemoveAttrAt(uint32_t aPos, nsAttrValue& aValue);
michael@0: 
michael@0:   // Returns attribute name at given position, *not* out-of-bounds safe
michael@0:   const nsAttrName* AttrNameAt(uint32_t aPos) const;
michael@0: 
michael@0:   // Returns attribute name at given position or null if aPos is out-of-bounds
michael@0:   const nsAttrName* GetSafeAttrNameAt(uint32_t aPos) const;
michael@0: 
michael@0:   const nsAttrName* GetExistingAttrNameFromQName(const nsAString& aName) const;
michael@0:   int32_t IndexOfAttr(nsIAtom* aLocalName, int32_t aNamespaceID = kNameSpaceID_None) const;
michael@0: 
michael@0:   nsresult SetAndTakeMappedAttr(nsIAtom* aLocalName, nsAttrValue& aValue,
michael@0:                                 nsMappedAttributeElement* aContent,
michael@0:                                 nsHTMLStyleSheet* aSheet);
michael@0:   nsresult SetMappedAttrStyleSheet(nsHTMLStyleSheet* aSheet) {
michael@0:     if (!mImpl || !mImpl->mMappedAttrs) {
michael@0:       return NS_OK;
michael@0:     }
michael@0:     return DoSetMappedAttrStyleSheet(aSheet);
michael@0:   }
michael@0:   void WalkMappedAttributeStyleRules(nsRuleWalker* aRuleWalker);
michael@0: 
michael@0:   void Compact();
michael@0: 
michael@0:   bool CanFitMoreAttrs() const
michael@0:   {
michael@0:     return AttrSlotCount() < ATTRCHILD_ARRAY_MAX_ATTR_COUNT ||
michael@0:            !AttrSlotIsTaken(ATTRCHILD_ARRAY_MAX_ATTR_COUNT - 1);
michael@0:   }
michael@0: 
michael@0:   size_t SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const;
michael@0:   bool HasMappedAttrs() const
michael@0:   {
michael@0:     return MappedAttrCount();
michael@0:   }
michael@0: 
michael@0: private:
michael@0:   nsAttrAndChildArray(const nsAttrAndChildArray& aOther) MOZ_DELETE;
michael@0:   nsAttrAndChildArray& operator=(const nsAttrAndChildArray& aOther) MOZ_DELETE;
michael@0: 
michael@0:   void Clear();
michael@0: 
michael@0:   uint32_t NonMappedAttrCount() const;
michael@0:   uint32_t MappedAttrCount() const;
michael@0: 
michael@0:   // Returns a non-null zero-refcount object.
michael@0:   nsMappedAttributes*
michael@0:   GetModifiableMapped(nsMappedAttributeElement* aContent,
michael@0:                       nsHTMLStyleSheet* aSheet,
michael@0:                       bool aWillAddAttr);
michael@0:   nsresult MakeMappedUnique(nsMappedAttributes* aAttributes);
michael@0: 
michael@0:   uint32_t AttrSlotsSize() const
michael@0:   {
michael@0:     return AttrSlotCount() * ATTRSIZE;
michael@0:   }
michael@0: 
michael@0:   uint32_t AttrSlotCount() const
michael@0:   {
michael@0:     return mImpl ? mImpl->mAttrAndChildCount & ATTRCHILD_ARRAY_ATTR_SLOTS_COUNT_MASK : 0;
michael@0:   }
michael@0: 
michael@0:   bool AttrSlotIsTaken(uint32_t aSlot) const
michael@0:   {
michael@0:     NS_PRECONDITION(aSlot < AttrSlotCount(), "out-of-bounds");
michael@0:     return mImpl->mBuffer[aSlot * ATTRSIZE];
michael@0:   }
michael@0: 
michael@0:   void SetChildCount(uint32_t aCount)
michael@0:   {
michael@0:     mImpl->mAttrAndChildCount = 
michael@0:         (mImpl->mAttrAndChildCount & ATTRCHILD_ARRAY_ATTR_SLOTS_COUNT_MASK) |
michael@0:         (aCount << ATTRCHILD_ARRAY_ATTR_SLOTS_BITS);
michael@0:   }
michael@0: 
michael@0:   void SetAttrSlotCount(uint32_t aCount)
michael@0:   {
michael@0:     mImpl->mAttrAndChildCount =
michael@0:         (mImpl->mAttrAndChildCount & ~ATTRCHILD_ARRAY_ATTR_SLOTS_COUNT_MASK) |
michael@0:         aCount;
michael@0:   }
michael@0: 
michael@0:   void SetAttrSlotAndChildCount(uint32_t aSlotCount, uint32_t aChildCount)
michael@0:   {
michael@0:     mImpl->mAttrAndChildCount = aSlotCount |
michael@0:       (aChildCount << ATTRCHILD_ARRAY_ATTR_SLOTS_BITS);
michael@0:   }
michael@0: 
michael@0:   bool GrowBy(uint32_t aGrowSize);
michael@0:   bool AddAttrSlot();
michael@0: 
michael@0:   /**
michael@0:    * Set *aPos to aChild and update sibling pointers as needed.  aIndex is the
michael@0:    * index at which aChild is actually being inserted.  aChildCount is the
michael@0:    * number of kids we had before the insertion.
michael@0:    */
michael@0:   inline void SetChildAtPos(void** aPos, nsIContent* aChild, uint32_t aIndex,
michael@0:                             uint32_t aChildCount);
michael@0: 
michael@0:   /**
michael@0:    * Guts of SetMappedAttrStyleSheet for the rare case when we have mapped attrs
michael@0:    */
michael@0:   nsresult DoSetMappedAttrStyleSheet(nsHTMLStyleSheet* aSheet);
michael@0: 
michael@0:   struct InternalAttr
michael@0:   {
michael@0:     nsAttrName mName;
michael@0:     nsAttrValue mValue;
michael@0:   };
michael@0: 
michael@0:   struct Impl {
michael@0:     uint32_t mAttrAndChildCount;
michael@0:     uint32_t mBufferSize;
michael@0:     nsMappedAttributes* mMappedAttrs;
michael@0:     void* mBuffer[1];
michael@0:   };
michael@0: 
michael@0:   Impl* mImpl;
michael@0: };
michael@0: 
michael@0: #endif