dom/base/nsStyleLinkElement.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
   2  *
   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 /*
   8  * A base class which implements nsIStyleSheetLinkingElement and can
   9  * be subclassed by various content nodes that want to load
  10  * stylesheets (<style>, <link>, processing instructions, etc).
  11  */
  12
  13 #ifndef nsStyleLinkElement_h___
  14 #define nsStyleLinkElement_h___
  15
  16 #include "mozilla/Attributes.h"
  17 #include "mozilla/CORSMode.h"
  18 #include "mozilla/CSSStyleSheet.h"
  19 #include "nsCOMPtr.h"
  20 #include "nsIStyleSheetLinkingElement.h"
  21 #include "nsTArray.h"
  22
  23 class nsIDocument;
  24 class nsIURI;
  25
  26 namespace mozilla {
  27 namespace dom {
  28 class ShadowRoot;
  29 } // namespace dom
  30 } // namespace mozilla
  31
  32 class nsStyleLinkElement : public nsIStyleSheetLinkingElement
  33 {
  34 public:
  35   nsStyleLinkElement();
  36   virtual ~nsStyleLinkElement();
  37
  38   NS_IMETHOD QueryInterface(REFNSIID aIID, void** aInstancePtr) MOZ_OVERRIDE = 0;
  39
  40   mozilla::CSSStyleSheet* GetSheet() const { return mStyleSheet; }
  41
  42   // nsIStyleSheetLinkingElement
  43   NS_IMETHOD SetStyleSheet(mozilla::CSSStyleSheet* aStyleSheet) MOZ_OVERRIDE;
  44   NS_IMETHOD_(mozilla::CSSStyleSheet*) GetStyleSheet() MOZ_OVERRIDE;
  45   NS_IMETHOD InitStyleLinkElement(bool aDontLoadStyle) MOZ_OVERRIDE;
  46   NS_IMETHOD UpdateStyleSheet(nsICSSLoaderObserver* aObserver,
  47                               bool* aWillNotify,
  48                               bool* aIsAlternate,
  49                               bool aForceReload) MOZ_OVERRIDE;
  50   NS_IMETHOD SetEnableUpdates(bool aEnableUpdates) MOZ_OVERRIDE;
  51   NS_IMETHOD GetCharset(nsAString& aCharset) MOZ_OVERRIDE;
  52
  53   virtual void OverrideBaseURI(nsIURI* aNewBaseURI) MOZ_OVERRIDE;
  54   virtual void SetLineNumber(uint32_t aLineNumber) MOZ_OVERRIDE;
  55
  56   enum RelValue {
  57     ePREFETCH =     0x00000001,
  58     eDNS_PREFETCH = 0x00000002,
  59     eSTYLESHEET =   0x00000004,
  60     eNEXT =         0x00000008,
  61     eALTERNATE =    0x00000010,
  62     eHTMLIMPORT =   0x00000020
  63   };
  64
  65   // The return value is a bitwise or of 0 or more RelValues.
  66   // aPrincipal is used to check if HTML imports is enabled for the
  67   // provided principal.
  68   static uint32_t ParseLinkTypes(const nsAString& aTypes,
  69                                  nsIPrincipal* aPrincipal);
  70
  71   static bool IsImportEnabled(nsIPrincipal* aPrincipal);
  72
  73   void UpdateStyleSheetInternal()
  74   {
  75     UpdateStyleSheetInternal(nullptr, nullptr);
  76   }
  77 protected:
  78   /**
  79    * @param aOldDocument should be non-null only if we're updating because we
  80    *                     removed the node from the document.
  81    * @param aForceUpdate true will force the update even if the URI has not
  82    *                     changed.  This should be used in cases when something
  83    *                     about the content that affects the resulting sheet
  84    *                     changed but the URI may not have changed.
  85    */
  86   nsresult UpdateStyleSheetInternal(nsIDocument *aOldDocument,
  87                                     mozilla::dom::ShadowRoot *aOldShadowRoot,
  88                                     bool aForceUpdate = false);
  89
  90   void UpdateStyleSheetScopedness(bool aIsNowScoped);
  91
  92   virtual already_AddRefed<nsIURI> GetStyleSheetURL(bool* aIsInline) = 0;
  93   virtual void GetStyleSheetInfo(nsAString& aTitle,
  94                                  nsAString& aType,
  95                                  nsAString& aMedia,
  96                                  bool* aIsScoped,
  97                                  bool* aIsAlternate) = 0;
  98
  99   virtual mozilla::CORSMode GetCORSMode() const
 100   {
 101     // Default to no CORS
 102     return mozilla::CORS_NONE;
 103   }
 104
 105   // CC methods
 106   void Unlink();
 107   void Traverse(nsCycleCollectionTraversalCallback &cb);
 108
 109 private:
 110   /**
 111    * @param aOldDocument should be non-null only if we're updating because we
 112    *                     removed the node from the document.
 113    * @param aOldShadowRoot The ShadowRoot that used to contain the style.
 114    *                     Passed as a parameter because on an update, the node
 115    *                     is removed from the tree before the sheet is removed
 116    *                     from the ShadowRoot.
 117    * @param aForceUpdate true will force the update even if the URI has not
 118    *                     changed.  This should be used in cases when something
 119    *                     about the content that affects the resulting sheet
 120    *                     changed but the URI may not have changed.
 121    */
 122   nsresult DoUpdateStyleSheet(nsIDocument* aOldDocument,
 123                               mozilla::dom::ShadowRoot* aOldShadowRoot,
 124                               nsICSSLoaderObserver* aObserver,
 125                               bool* aWillNotify,
 126                               bool* aIsAlternate,
 127                               bool aForceUpdate);
 128
 129   nsRefPtr<mozilla::CSSStyleSheet> mStyleSheet;
 130 protected:
 131   bool mDontLoadStyle;
 132   bool mUpdatesEnabled;
 133   uint32_t mLineNumber;
 134 };
 135
 136 #endif /* nsStyleLinkElement_h___ */
 137