content/base/src/Link.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
   2  * vim: sw=2 ts=2 et :
   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  * This is the base class for all link classes.
   9  */
  10
  11 #ifndef mozilla_dom_Link_h__
  12 #define mozilla_dom_Link_h__
  13
  14 #include "mozilla/IHistory.h"
  15 #include "mozilla/MemoryReporting.h"
  16 #include "nsEventStates.h"
  17 #include "nsIContent.h"
  18
  19 namespace mozilla {
  20 namespace dom {
  21
  22 class Element;
  23
  24 #define MOZILLA_DOM_LINK_IMPLEMENTATION_IID               \
  25 { 0xb25edee6, 0xdd35, 0x4f8b,                             \
  26   { 0xab, 0x90, 0x66, 0xd0, 0xbd, 0x3c, 0x22, 0xd5 } }
  27
  28 class Link : public nsISupports
  29 {
  30 public:
  31   NS_DECLARE_STATIC_IID_ACCESSOR(MOZILLA_DOM_LINK_IMPLEMENTATION_IID)
  32
  33   /**
  34    * aElement is the element pointer corresponding to this link.
  35    */
  36   Link(Element* aElement);
  37   virtual void SetLinkState(nsLinkState aState);
  38
  39   /**
  40    * @return NS_EVENT_STATE_VISITED if this link is visited,
  41    *         NS_EVENT_STATE_UNVISTED if this link is not visited, or 0 if this
  42    *         link is not actually a link.
  43    */
  44   nsEventStates LinkState() const;
  45
  46   /**
  47    * @return the URI this link is for, if available.
  48    */
  49   nsIURI* GetURI() const;
  50   virtual nsIURI* GetURIExternal() const {
  51     return GetURI();
  52   }
  53
  54   /**
  55    * Helper methods for modifying and obtaining parts of the URI of the Link.
  56    */
  57   void SetProtocol(const nsAString &aProtocol);
  58   void SetUsername(const nsAString &aUsername);
  59   void SetPassword(const nsAString &aPassword);
  60   void SetHost(const nsAString &aHost);
  61   void SetHostname(const nsAString &aHostname);
  62   void SetPathname(const nsAString &aPathname);
  63   void SetSearch(const nsAString &aSearch);
  64   void SetPort(const nsAString &aPort);
  65   void SetHash(const nsAString &aHash);
  66   void GetOrigin(nsAString &aOrigin);
  67   void GetProtocol(nsAString &_protocol);
  68   void GetUsername(nsAString &aUsername);
  69   void GetPassword(nsAString &aPassword);
  70   void GetHost(nsAString &_host);
  71   void GetHostname(nsAString &_hostname);
  72   void GetPathname(nsAString &_pathname);
  73   void GetSearch(nsAString &_search);
  74   void GetPort(nsAString &_port);
  75   void GetHash(nsAString &_hash);
  76
  77   /**
  78    * Invalidates any link caching, and resets the state to the default.
  79    *
  80    * @param aNotify
  81    *        true if ResetLinkState should notify the owning document about style
  82    *        changes or false if it should not.
  83    */
  84   void ResetLinkState(bool aNotify, bool aHasHref);
  85
  86   // This method nevers returns a null element.
  87   Element* GetElement() const { return mElement; }
  88
  89   /**
  90    * DNS prefetch has been deferred until later, e.g. page load complete.
  91    */
  92   virtual void OnDNSPrefetchDeferred() { /*do nothing*/ }
  93
  94   /**
  95    * DNS prefetch has been submitted to Host Resolver.
  96    */
  97   virtual void OnDNSPrefetchRequested() { /*do nothing*/ }
  98
  99   /**
 100    * Checks if DNS Prefetching is ok
 101    *
 102    * @returns boolean
 103    *          Defaults to true; should be overridden for specialised cases
 104    */
 105   virtual bool HasDeferredDNSPrefetchRequest() { return true; }
 106
 107   virtual size_t
 108     SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const;
 109
 110   bool ElementHasHref() const;
 111
 112 protected:
 113   virtual ~Link();
 114
 115   /**
 116    * Return true if the link has associated URI.
 117    */
 118   bool HasURI() const
 119   {
 120     if (HasCachedURI()) {
 121       return true;
 122     }
 123
 124     return !!GetURI();
 125   }
 126
 127   nsIURI* GetCachedURI() const { return mCachedURI; }
 128   bool HasCachedURI() const { return !!mCachedURI; }
 129
 130 private:
 131   /**
 132    * Unregisters from History so this node no longer gets notifications about
 133    * changes to visitedness.
 134    */
 135   void UnregisterFromHistory();
 136
 137   already_AddRefed<nsIURI> GetURIToMutate();
 138   void SetHrefAttribute(nsIURI *aURI);
 139
 140   mutable nsCOMPtr<nsIURI> mCachedURI;
 141
 142   Element * const mElement;
 143
 144   // Strong reference to History.  The link has to unregister before History
 145   // can disappear.
 146   nsCOMPtr<IHistory> mHistory;
 147
 148   uint16_t mLinkState;
 149
 150   bool mNeedsRegistration;
 151
 152   bool mRegistered;
 153 };
 154
 155 NS_DEFINE_STATIC_IID_ACCESSOR(Link, MOZILLA_DOM_LINK_IMPLEMENTATION_IID)
 156
 157 } // namespace dom
 158 } // namespace mozilla
 159
 160 #endif // mozilla_dom_Link_h__