Line data    Source code

       1             : /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
       2             : /* This Source Code Form is subject to the terms of the Mozilla Public
       3             :  * License, v. 2.0. If a copy of the MPL was not distributed with this
       4             :  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
       5             : 
       6             : #include "nsTreeStyleCache.h"
       7             : #include "nsStyleSet.h"
       8             : #include "mozilla/dom/Element.h"
       9             : #include "mozilla/StyleSetHandle.h"
      10             : #include "mozilla/StyleSetHandleInlines.h"
      11             : 
      12           0 : nsTreeStyleCache::Transition::Transition(DFAState aState, nsIAtom* aSymbol)
      13           0 :   : mState(aState), mInputSymbol(aSymbol)
      14             : {
      15           0 : }
      16             : 
      17             : bool
      18           0 : nsTreeStyleCache::Transition::operator==(const Transition& aOther) const
      19             : {
      20           0 :   return aOther.mState == mState && aOther.mInputSymbol == mInputSymbol;
      21             : }
      22             : 
      23             : uint32_t
      24           0 : nsTreeStyleCache::Transition::Hash() const
      25             : {
      26             :   // Make a 32-bit integer that combines the low-order 16 bits of the state and the input symbol.
      27           0 :   uint32_t hb = mState << 16;
      28           0 :   uint32_t lb = (NS_PTR_TO_UINT32(mInputSymbol.get()) << 16) >> 16;
      29           0 :   return hb+lb;
      30             : }
      31             : 
      32             : 
      33             : // The style context cache impl
      34             : nsStyleContext*
      35           0 : nsTreeStyleCache::GetStyleContext(nsICSSPseudoComparator* aComparator,
      36             :                                   nsPresContext* aPresContext,
      37             :                                   nsIContent* aContent,
      38             :                                   nsStyleContext* aContext,
      39             :                                   nsICSSAnonBoxPseudo* aPseudoElement,
      40             :                                   const AtomArray & aInputWord)
      41             : {
      42           0 :   MOZ_ASSERT(nsCSSAnonBoxes::IsTreePseudoElement(aPseudoElement));
      43             : 
      44           0 :   uint32_t count = aInputWord.Length();
      45             : 
      46             :   // Go ahead and init the transition table.
      47           0 :   if (!mTransitionTable) {
      48             :     // Automatic miss. Build the table
      49           0 :     mTransitionTable = new TransitionTable();
      50             :   }
      51             : 
      52             :   // The first transition is always made off the supplied pseudo-element.
      53           0 :   Transition transition(0, aPseudoElement);
      54           0 :   DFAState currState = mTransitionTable->Get(transition);
      55             : 
      56           0 :   if (!currState) {
      57             :     // We had a miss. Make a new state and add it to our hash.
      58           0 :     currState = mNextState;
      59           0 :     mNextState++;
      60           0 :     mTransitionTable->Put(transition, currState);
      61             :   }
      62             : 
      63           0 :   for (uint32_t i = 0; i < count; i++) {
      64           0 :     Transition transition(currState, aInputWord[i]);
      65           0 :     currState = mTransitionTable->Get(transition);
      66             : 
      67           0 :     if (!currState) {
      68             :       // We had a miss. Make a new state and add it to our hash.
      69           0 :       currState = mNextState;
      70           0 :       mNextState++;
      71           0 :       mTransitionTable->Put(transition, currState);
      72             :     }
      73             :   }
      74             : 
      75             :   // We're in a final state.
      76             :   // Look up our style context for this state.
      77           0 :   nsStyleContext* result = nullptr;
      78           0 :   if (mCache) {
      79           0 :     result = mCache->GetWeak(currState);
      80             :   }
      81           0 :   if (!result) {
      82             :     // We missed the cache. Resolve this pseudo-style.
      83             :     // XXXheycam ServoStyleSets do not support XUL tree styles.
      84           0 :     RefPtr<nsStyleContext> newResult;
      85           0 :     if (aPresContext->StyleSet()->IsServo()) {
      86           0 :       NS_ERROR("stylo: ServoStyleSets should not support XUL tree styles yet");
      87           0 :       newResult = aPresContext->StyleSet()->
      88           0 :         ResolveStyleForPlaceholder();
      89             :     } else {
      90           0 :       newResult = aPresContext->StyleSet()->AsGecko()->
      91           0 :         ResolveXULTreePseudoStyle(aContent->AsElement(), aPseudoElement,
      92           0 :                                   aContext, aComparator);
      93             :     }
      94             : 
      95             :     // Put the style context in our table, transferring the owning reference to the table.
      96           0 :     if (!mCache) {
      97           0 :       mCache = new StyleContextCache();
      98             :     }
      99           0 :     result = newResult.get();
     100           0 :     mCache->Put(currState, newResult.forget());
     101             :   }
     102             : 
     103           0 :   return result;
     104             : }
     105             :