/* -*- 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/. */ /* * A unique per-element set of attributes that is used as an * nsIStyleRule; used to implement presentational attributes. */ #include "nsMappedAttributes.h" #include "mozilla/Assertions.h" #include "nsHTMLStyleSheet.h" #include "mozilla/DeclarationBlock.h" #include "mozilla/HashFunctions.h" #include "mozilla/MappedDeclarations.h" #include "mozilla/MemoryReporting.h" using namespace mozilla; bool nsMappedAttributes::sShuttingDown = false; nsTArray* nsMappedAttributes::sCachedMappedAttributeAllocations = nullptr; void nsMappedAttributes::Shutdown() { sShuttingDown = true; if (sCachedMappedAttributeAllocations) { for (uint32_t i = 0; i < sCachedMappedAttributeAllocations->Length(); ++i) { void* cachedValue = (*sCachedMappedAttributeAllocations)[i]; ::operator delete(cachedValue); } } delete sCachedMappedAttributeAllocations; sCachedMappedAttributeAllocations = nullptr; } nsMappedAttributes::nsMappedAttributes(nsHTMLStyleSheet* aSheet, nsMapRuleToAttributesFunc aMapRuleFunc) : mAttrCount(0), mSheet(aSheet), mRuleMapper(aMapRuleFunc), mServoStyle(nullptr) { MOZ_ASSERT(mRefCnt == 0); // Ensure caching works as expected. } nsMappedAttributes::nsMappedAttributes(const nsMappedAttributes& aCopy) : mAttrCount(aCopy.mAttrCount), mSheet(aCopy.mSheet), mRuleMapper(aCopy.mRuleMapper), // This is only called by ::Clone, which is used to create independent // nsMappedAttributes objects which should not share a DeclarationBlock mServoStyle(nullptr) { MOZ_ASSERT(mBufferSize >= aCopy.mAttrCount, "can't fit attributes"); MOZ_ASSERT(mRefCnt == 0); // Ensure caching works as expected. uint32_t i; for (i = 0; i < mAttrCount; ++i) { new (&Attrs()[i]) InternalAttr(aCopy.Attrs()[i]); } } nsMappedAttributes::~nsMappedAttributes() { if (mSheet) { mSheet->DropMappedAttributes(this); } uint32_t i; for (i = 0; i < mAttrCount; ++i) { Attrs()[i].~InternalAttr(); } } nsMappedAttributes* nsMappedAttributes::Clone(bool aWillAddAttr) { uint32_t extra = aWillAddAttr ? 1 : 0; // This will call the overridden operator new return new (mAttrCount + extra) nsMappedAttributes(*this); } void* nsMappedAttributes::operator new(size_t aSize, uint32_t aAttrCount) noexcept(true) { size_t size = aSize + aAttrCount * sizeof(InternalAttr); // aSize will include the mAttrs buffer so subtract that. // We don't want to under-allocate, however, so do not subtract // if we have zero attributes. The zero attribute case only happens // for 's mapped attributes if (aAttrCount != 0) { size -= sizeof(void* [1]); } if (sCachedMappedAttributeAllocations) { void* cached = sCachedMappedAttributeAllocations->SafeElementAt(aAttrCount); if (cached) { (*sCachedMappedAttributeAllocations)[aAttrCount] = nullptr; return cached; } } void* newAttrs = ::operator new(size); #ifdef DEBUG static_cast(newAttrs)->mBufferSize = aAttrCount; #endif return newAttrs; } void nsMappedAttributes::LastRelease() { if (!sShuttingDown) { if (!sCachedMappedAttributeAllocations) { sCachedMappedAttributeAllocations = new nsTArray(); } // Ensure the cache array is at least mAttrCount + 1 long and // that each item is either null or pointing to a cached item. // The size of the array is capped because mapped attributes are defined // statically in element implementations. sCachedMappedAttributeAllocations->SetCapacity(mAttrCount + 1); for (uint32_t i = sCachedMappedAttributeAllocations->Length(); i < (uint32_t(mAttrCount) + 1); ++i) { sCachedMappedAttributeAllocations->AppendElement(nullptr); } if (!(*sCachedMappedAttributeAllocations)[mAttrCount]) { void* memoryToCache = this; this->~nsMappedAttributes(); (*sCachedMappedAttributeAllocations)[mAttrCount] = memoryToCache; return; } } delete this; } void nsMappedAttributes::SetAndSwapAttr(nsAtom* aAttrName, nsAttrValue& aValue, bool* aValueWasSet) { MOZ_ASSERT(aAttrName, "null name"); *aValueWasSet = false; uint32_t i; for (i = 0; i < mAttrCount && !Attrs()[i].mName.IsSmaller(aAttrName); ++i) { if (Attrs()[i].mName.Equals(aAttrName)) { Attrs()[i].mValue.SwapValueWith(aValue); *aValueWasSet = true; return; } } MOZ_ASSERT(mBufferSize >= mAttrCount + 1, "can't fit attributes"); if (mAttrCount != i) { memmove(&Attrs()[i + 1], &Attrs()[i], (mAttrCount - i) * sizeof(InternalAttr)); } new (&Attrs()[i].mName) nsAttrName(aAttrName); new (&Attrs()[i].mValue) nsAttrValue(); Attrs()[i].mValue.SwapValueWith(aValue); ++mAttrCount; } const nsAttrValue* nsMappedAttributes::GetAttr(const nsAtom* aAttrName) const { MOZ_ASSERT(aAttrName, "null name"); for (uint32_t i = 0; i < mAttrCount; ++i) { if (Attrs()[i].mName.Equals(aAttrName)) { return &Attrs()[i].mValue; } } return nullptr; } const nsAttrValue* nsMappedAttributes::GetAttr( const nsAString& aAttrName) const { for (uint32_t i = 0; i < mAttrCount; ++i) { if (Attrs()[i].mName.Atom()->Equals(aAttrName)) { return &Attrs()[i].mValue; } } return nullptr; } bool nsMappedAttributes::Equals(const nsMappedAttributes* aOther) const { if (this == aOther) { return true; } if (mRuleMapper != aOther->mRuleMapper || mAttrCount != aOther->mAttrCount) { return false; } uint32_t i; for (i = 0; i < mAttrCount; ++i) { if (!Attrs()[i].mName.Equals(aOther->Attrs()[i].mName) || !Attrs()[i].mValue.Equals(aOther->Attrs()[i].mValue)) { return false; } } return true; } PLDHashNumber nsMappedAttributes::HashValue() const { PLDHashNumber hash = HashGeneric(mRuleMapper); uint32_t i; for (i = 0; i < mAttrCount; ++i) { hash = AddToHash(hash, Attrs()[i].mName.HashValue(), Attrs()[i].mValue.HashValue()); } return hash; } void nsMappedAttributes::SetStyleSheet(nsHTMLStyleSheet* aSheet) { MOZ_ASSERT(!mSheet, "Should either drop the sheet reference manually, " "or drop the mapped attributes"); mSheet = aSheet; // not ref counted } void nsMappedAttributes::RemoveAttrAt(uint32_t aPos, nsAttrValue& aValue) { Attrs()[aPos].mValue.SwapValueWith(aValue); Attrs()[aPos].~InternalAttr(); memmove(&Attrs()[aPos], &Attrs()[aPos + 1], (mAttrCount - aPos - 1) * sizeof(InternalAttr)); mAttrCount--; } const nsAttrName* nsMappedAttributes::GetExistingAttrNameFromQName( const nsAString& aName) const { uint32_t i; for (i = 0; i < mAttrCount; ++i) { if (Attrs()[i].mName.IsAtom()) { if (Attrs()[i].mName.Atom()->Equals(aName)) { return &Attrs()[i].mName; } } else { if (Attrs()[i].mName.NodeInfo()->QualifiedNameEquals(aName)) { return &Attrs()[i].mName; } } } return nullptr; } int32_t nsMappedAttributes::IndexOfAttr(const nsAtom* aLocalName) const { uint32_t i; for (i = 0; i < mAttrCount; ++i) { if (Attrs()[i].mName.Equals(aLocalName)) { return i; } } return -1; } size_t nsMappedAttributes::SizeOfIncludingThis( MallocSizeOf aMallocSizeOf) const { MOZ_ASSERT(mBufferSize >= mAttrCount, "can't fit attributes"); size_t n = aMallocSizeOf(this); for (uint16_t i = 0; i < mAttrCount; ++i) { n += Attrs()[i].mValue.SizeOfExcludingThis(aMallocSizeOf); } return n; } void nsMappedAttributes::LazilyResolveServoDeclaration(dom::Document* aDoc) { MOZ_ASSERT(!mServoStyle, "LazilyResolveServoDeclaration should not be called if " "mServoStyle is already set"); if (mRuleMapper) { MappedDeclarations declarations( aDoc, Servo_DeclarationBlock_CreateEmpty().Consume()); (*mRuleMapper)(this, declarations); mServoStyle = declarations.TakeDeclarationBlock(); } }