layout/style/ServoCSSRuleList.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 /* representation of CSSRuleList for stylo */
   8
   9 #ifndef mozilla_ServoCSSRuleList_h
  10 #define mozilla_ServoCSSRuleList_h
  11
  12 #include "mozilla/ServoBindingTypes.h"
  13 #include "mozilla/dom/CSSRuleList.h"
  14
  15 namespace mozilla {
  16
  17 namespace dom {
  18 class CSSStyleRule;
  19 }  // namespace dom
  20 class StyleSheet;
  21 namespace css {
  22 class GroupRule;
  23 class Rule;
  24 }  // namespace css
  25
  26 class ServoCSSRuleList final : public dom::CSSRuleList {
  27  public:
  28   ServoCSSRuleList(already_AddRefed<StyleLockedCssRules> aRawRules,
  29                    StyleSheet* aSheet, css::GroupRule* aParentRule);
  30   css::GroupRule* GetParentRule() const { return mParentRule; }
  31   void DropSheetReference();
  32   void DropParentRuleReference();
  33
  34   void DropReferences() {
  35     DropSheetReference();
  36     DropParentRuleReference();
  37   }
  38
  39   NS_DECL_ISUPPORTS_INHERITED
  40   NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(ServoCSSRuleList, dom::CSSRuleList)
  41
  42   StyleSheet* GetParentObject() final { return mStyleSheet; }
  43
  44   css::Rule* IndexedGetter(uint32_t aIndex, bool& aFound) final;
  45   uint32_t Length() final { return mRules.Length(); }
  46
  47   css::Rule* GetRule(uint32_t aIndex);
  48   nsresult InsertRule(const nsACString& aRule, uint32_t aIndex);
  49   nsresult DeleteRule(uint32_t aIndex);
  50
  51   // aFromClone says whether this comes from a clone of the stylesheet (and thus
  52   // we should also fix up the wrappers for the individual rules in the rule
  53   // lists).
  54   void SetRawContents(RefPtr<StyleLockedCssRules>, bool aFromClone);
  55   void SetRawAfterClone(RefPtr<StyleLockedCssRules> aRules) {
  56     SetRawContents(std::move(aRules), /* aFromClone = */ true);
  57   }
  58
  59  private:
  60   virtual ~ServoCSSRuleList();
  61
  62   // XXX Is it possible to have an address lower than or equal to 255?
  63   //     Is it possible to have more than 255 CSS rule types?
  64   static const uintptr_t kMaxRuleType = UINT8_MAX;
  65
  66   static uintptr_t CastToUint(css::Rule* aPtr) {
  67     return reinterpret_cast<uintptr_t>(aPtr);
  68   }
  69   static css::Rule* CastToPtr(uintptr_t aInt) {
  70     MOZ_ASSERT(aInt > kMaxRuleType);
  71     return reinterpret_cast<css::Rule*>(aInt);
  72   }
  73
  74   template <typename Func>
  75   void EnumerateInstantiatedRules(Func aCallback);
  76
  77   void DropAllRules();
  78   void ResetRules();
  79
  80   bool IsReadOnly() const;
  81
  82   // mStyleSheet may be nullptr when it drops the reference to us.
  83   StyleSheet* mStyleSheet = nullptr;
  84   // mParentRule is nullptr if it isn't a nested rule list.
  85   css::GroupRule* mParentRule = nullptr;
  86   RefPtr<StyleLockedCssRules> mRawRules;
  87   // Array stores either a number indicating rule type, or a pointer to
  88   // css::Rule. If the value is less than kMaxRuleType, the given rule
  89   // instance has not been constructed, and the value means the type
  90   // of the rule. Otherwise, it is a pointer.
  91   nsTArray<uintptr_t> mRules;
  92 };
  93
  94 }  // namespace mozilla
  95
  96 #endif  // mozilla_ServoCSSRuleList_h