1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/content/base/src/nsAttrAndChildArray.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,215 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +/*
1.10 + * Storage of the children and attributes of a DOM node; storage for
1.11 + * the two is unified to minimize footprint.
1.12 + */
1.13 +
1.14 +#ifndef nsAttrAndChildArray_h___
1.15 +#define nsAttrAndChildArray_h___
1.16 +
1.17 +#include "mozilla/Attributes.h"
1.18 +#include "mozilla/MemoryReporting.h"
1.19 +
1.20 +#include "nscore.h"
1.21 +#include "nsAttrName.h"
1.22 +#include "nsAttrValue.h"
1.23 +#include "nsCaseTreatment.h"
1.24 +
1.25 +class nsINode;
1.26 +class nsIContent;
1.27 +class nsMappedAttributes;
1.28 +class nsHTMLStyleSheet;
1.29 +class nsRuleWalker;
1.30 +class nsMappedAttributeElement;
1.31 +
1.32 +#define ATTRCHILD_ARRAY_GROWSIZE 8
1.33 +#define ATTRCHILD_ARRAY_LINEAR_THRESHOLD 32
1.34 +
1.35 +#define ATTRCHILD_ARRAY_ATTR_SLOTS_BITS 10
1.36 +
1.37 +#define ATTRCHILD_ARRAY_MAX_ATTR_COUNT \
1.38 + ((1 << ATTRCHILD_ARRAY_ATTR_SLOTS_BITS) - 1)
1.39 +
1.40 +#define ATTRCHILD_ARRAY_MAX_CHILD_COUNT \
1.41 + (~uint32_t(0) >> ATTRCHILD_ARRAY_ATTR_SLOTS_BITS)
1.42 +
1.43 +#define ATTRCHILD_ARRAY_ATTR_SLOTS_COUNT_MASK \
1.44 + ((1 << ATTRCHILD_ARRAY_ATTR_SLOTS_BITS) - 1)
1.45 +
1.46 +
1.47 +#define ATTRSIZE (sizeof(InternalAttr) / sizeof(void*))
1.48 +
1.49 +class nsAttrAndChildArray
1.50 +{
1.51 +public:
1.52 + nsAttrAndChildArray();
1.53 + ~nsAttrAndChildArray();
1.54 +
1.55 + uint32_t ChildCount() const
1.56 + {
1.57 + return mImpl ? (mImpl->mAttrAndChildCount >> ATTRCHILD_ARRAY_ATTR_SLOTS_BITS) : 0;
1.58 + }
1.59 + nsIContent* ChildAt(uint32_t aPos) const
1.60 + {
1.61 + NS_ASSERTION(aPos < ChildCount(), "out-of-bounds access in nsAttrAndChildArray");
1.62 + return reinterpret_cast<nsIContent*>(mImpl->mBuffer[AttrSlotsSize() + aPos]);
1.63 + }
1.64 + nsIContent* GetSafeChildAt(uint32_t aPos) const;
1.65 + nsIContent * const * GetChildArray(uint32_t* aChildCount) const;
1.66 + nsresult AppendChild(nsIContent* aChild)
1.67 + {
1.68 + return InsertChildAt(aChild, ChildCount());
1.69 + }
1.70 + nsresult InsertChildAt(nsIContent* aChild, uint32_t aPos);
1.71 + void RemoveChildAt(uint32_t aPos);
1.72 + // Like RemoveChildAt but hands the reference to the child being
1.73 + // removed back to the caller instead of just releasing it.
1.74 + already_AddRefed<nsIContent> TakeChildAt(uint32_t aPos);
1.75 + int32_t IndexOfChild(const nsINode* aPossibleChild) const;
1.76 +
1.77 + bool HasAttrs() const
1.78 + {
1.79 + return MappedAttrCount() || (AttrSlotCount() && AttrSlotIsTaken(0));
1.80 + }
1.81 +
1.82 + uint32_t AttrCount() const;
1.83 + const nsAttrValue* GetAttr(nsIAtom* aLocalName,
1.84 + int32_t aNamespaceID = kNameSpaceID_None) const;
1.85 + // As above but using a string attr name and always using
1.86 + // kNameSpaceID_None. This is always case-sensitive.
1.87 + const nsAttrValue* GetAttr(const nsAString& aName) const;
1.88 + // Get an nsAttrValue by qualified name. Can optionally do
1.89 + // ASCII-case-insensitive name matching.
1.90 + const nsAttrValue* GetAttr(const nsAString& aName,
1.91 + nsCaseTreatment aCaseSensitive) const;
1.92 + const nsAttrValue* AttrAt(uint32_t aPos) const;
1.93 + nsresult SetAndTakeAttr(nsIAtom* aLocalName, nsAttrValue& aValue);
1.94 + nsresult SetAndTakeAttr(nsINodeInfo* aName, nsAttrValue& aValue);
1.95 +
1.96 + // Remove the attr at position aPos. The value of the attr is placed in
1.97 + // aValue; any value that was already in aValue is destroyed.
1.98 + nsresult RemoveAttrAt(uint32_t aPos, nsAttrValue& aValue);
1.99 +
1.100 + // Returns attribute name at given position, *not* out-of-bounds safe
1.101 + const nsAttrName* AttrNameAt(uint32_t aPos) const;
1.102 +
1.103 + // Returns attribute name at given position or null if aPos is out-of-bounds
1.104 + const nsAttrName* GetSafeAttrNameAt(uint32_t aPos) const;
1.105 +
1.106 + const nsAttrName* GetExistingAttrNameFromQName(const nsAString& aName) const;
1.107 + int32_t IndexOfAttr(nsIAtom* aLocalName, int32_t aNamespaceID = kNameSpaceID_None) const;
1.108 +
1.109 + nsresult SetAndTakeMappedAttr(nsIAtom* aLocalName, nsAttrValue& aValue,
1.110 + nsMappedAttributeElement* aContent,
1.111 + nsHTMLStyleSheet* aSheet);
1.112 + nsresult SetMappedAttrStyleSheet(nsHTMLStyleSheet* aSheet) {
1.113 + if (!mImpl || !mImpl->mMappedAttrs) {
1.114 + return NS_OK;
1.115 + }
1.116 + return DoSetMappedAttrStyleSheet(aSheet);
1.117 + }
1.118 + void WalkMappedAttributeStyleRules(nsRuleWalker* aRuleWalker);
1.119 +
1.120 + void Compact();
1.121 +
1.122 + bool CanFitMoreAttrs() const
1.123 + {
1.124 + return AttrSlotCount() < ATTRCHILD_ARRAY_MAX_ATTR_COUNT ||
1.125 + !AttrSlotIsTaken(ATTRCHILD_ARRAY_MAX_ATTR_COUNT - 1);
1.126 + }
1.127 +
1.128 + size_t SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const;
1.129 + bool HasMappedAttrs() const
1.130 + {
1.131 + return MappedAttrCount();
1.132 + }
1.133 +
1.134 +private:
1.135 + nsAttrAndChildArray(const nsAttrAndChildArray& aOther) MOZ_DELETE;
1.136 + nsAttrAndChildArray& operator=(const nsAttrAndChildArray& aOther) MOZ_DELETE;
1.137 +
1.138 + void Clear();
1.139 +
1.140 + uint32_t NonMappedAttrCount() const;
1.141 + uint32_t MappedAttrCount() const;
1.142 +
1.143 + // Returns a non-null zero-refcount object.
1.144 + nsMappedAttributes*
1.145 + GetModifiableMapped(nsMappedAttributeElement* aContent,
1.146 + nsHTMLStyleSheet* aSheet,
1.147 + bool aWillAddAttr);
1.148 + nsresult MakeMappedUnique(nsMappedAttributes* aAttributes);
1.149 +
1.150 + uint32_t AttrSlotsSize() const
1.151 + {
1.152 + return AttrSlotCount() * ATTRSIZE;
1.153 + }
1.154 +
1.155 + uint32_t AttrSlotCount() const
1.156 + {
1.157 + return mImpl ? mImpl->mAttrAndChildCount & ATTRCHILD_ARRAY_ATTR_SLOTS_COUNT_MASK : 0;
1.158 + }
1.159 +
1.160 + bool AttrSlotIsTaken(uint32_t aSlot) const
1.161 + {
1.162 + NS_PRECONDITION(aSlot < AttrSlotCount(), "out-of-bounds");
1.163 + return mImpl->mBuffer[aSlot * ATTRSIZE];
1.164 + }
1.165 +
1.166 + void SetChildCount(uint32_t aCount)
1.167 + {
1.168 + mImpl->mAttrAndChildCount =
1.169 + (mImpl->mAttrAndChildCount & ATTRCHILD_ARRAY_ATTR_SLOTS_COUNT_MASK) |
1.170 + (aCount << ATTRCHILD_ARRAY_ATTR_SLOTS_BITS);
1.171 + }
1.172 +
1.173 + void SetAttrSlotCount(uint32_t aCount)
1.174 + {
1.175 + mImpl->mAttrAndChildCount =
1.176 + (mImpl->mAttrAndChildCount & ~ATTRCHILD_ARRAY_ATTR_SLOTS_COUNT_MASK) |
1.177 + aCount;
1.178 + }
1.179 +
1.180 + void SetAttrSlotAndChildCount(uint32_t aSlotCount, uint32_t aChildCount)
1.181 + {
1.182 + mImpl->mAttrAndChildCount = aSlotCount |
1.183 + (aChildCount << ATTRCHILD_ARRAY_ATTR_SLOTS_BITS);
1.184 + }
1.185 +
1.186 + bool GrowBy(uint32_t aGrowSize);
1.187 + bool AddAttrSlot();
1.188 +
1.189 + /**
1.190 + * Set *aPos to aChild and update sibling pointers as needed. aIndex is the
1.191 + * index at which aChild is actually being inserted. aChildCount is the
1.192 + * number of kids we had before the insertion.
1.193 + */
1.194 + inline void SetChildAtPos(void** aPos, nsIContent* aChild, uint32_t aIndex,
1.195 + uint32_t aChildCount);
1.196 +
1.197 + /**
1.198 + * Guts of SetMappedAttrStyleSheet for the rare case when we have mapped attrs
1.199 + */
1.200 + nsresult DoSetMappedAttrStyleSheet(nsHTMLStyleSheet* aSheet);
1.201 +
1.202 + struct InternalAttr
1.203 + {
1.204 + nsAttrName mName;
1.205 + nsAttrValue mValue;
1.206 + };
1.207 +
1.208 + struct Impl {
1.209 + uint32_t mAttrAndChildCount;
1.210 + uint32_t mBufferSize;
1.211 + nsMappedAttributes* mMappedAttrs;
1.212 + void* mBuffer[1];
1.213 + };
1.214 +
1.215 + Impl* mImpl;
1.216 +};
1.217 +
1.218 +#endif
