content/xbl/src/nsXBLService.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* ***** BEGIN LICENSE BLOCK *****
   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   4  *
   5  * The contents of this file are subject to the Mozilla Public License Version
   6  * 1.1 (the "License"); you may not use this file except in compliance with
   7  * the License. You may obtain a copy of the License at
   8  * http://www.mozilla.org/MPL/
   9  *
  10  * Software distributed under the License is distributed on an "AS IS" basis,
  11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  12  * for the specific language governing rights and limitations under the
  13  * License.
  14  *
  15  * The Original Code is Mozilla Communicator client code.
  16  *
  17  * The Initial Developer of the Original Code is
  18  * Netscape Communications Corporation.
  19  * Portions created by the Initial Developer are Copyright (C) 1998
  20  * the Initial Developer. All Rights Reserved.
  21  *
  22  * Contributor(s):
  23  *   Original Author: David W. Hyatt (hyatt@netscape.com)
  24  *   - Brendan Eich (brendan@mozilla.org)
  25  *   - Mike Pinkerton (pinkerton@netscape.com)
  26  *
  27  * Alternatively, the contents of this file may be used under the terms of
  28  * either of the GNU General Public License Version 2 or later (the "GPL"),
  29  * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  30  * in which case the provisions of the GPL or the LGPL are applicable instead
  31  * of those above. If you wish to allow use of your version of this file only
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  34  * decision by deleting the provisions above and replace them with the notice
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  36  * the provisions above, a recipient may use your version of this file under
  37  * the terms of any one of the MPL, the GPL or the LGPL.
  38  *
  39  * ***** END LICENSE BLOCK ***** */
  40
  41 //////////////////////////////////////////////////////////////////////////////////////////
  42
  43 #include "nsIXBLService.h"
  44 #include "nsIObserver.h"
  45 #include "nsWeakReference.h"
  46 #include "jsapi.h"              // nsXBLJSClass derives from JSClass
  47 #include "jsclist.h"            // nsXBLJSClass derives from JSCList
  48 #include "nsFixedSizeAllocator.h"
  49 #include "nsTArray.h"
  50
  51 class nsXBLBinding;
  52 class nsIXBLDocumentInfo;
  53 class nsIContent;
  54 class nsIDocument;
  55 class nsIAtom;
  56 class nsString;
  57 class nsIURI;
  58 class nsSupportsHashtable;
  59 class nsHashtable;
  60
  61 class nsXBLService : public nsIXBLService,
  62                      public nsIObserver,
  63                      public nsSupportsWeakReference
  64 {
  65   NS_DECL_ISUPPORTS
  66
  67   // This function loads a particular XBL file and installs all of the bindings
  68   // onto the element.  aOriginPrincipal must not be null here.
  69   NS_IMETHOD LoadBindings(nsIContent* aContent, nsIURI* aURL,
  70                           nsIPrincipal* aOriginPrincipal, PRBool aAugmentFlag,
  71                           nsXBLBinding** aBinding, PRBool* aResolveStyle);
  72
  73   // Indicates whether or not a binding is fully loaded.
  74   NS_IMETHOD BindingReady(nsIContent* aBoundElement, nsIURI* aURI, PRBool* aIsReady);
  75
  76   // Gets the object's base class type.
  77   NS_IMETHOD ResolveTag(nsIContent* aContent, PRInt32* aNameSpaceID, nsIAtom** aResult);
  78
  79   // This method checks the hashtable and then calls FetchBindingDocument on a
  80   // miss.  aOriginPrincipal or aBoundDocument may be null to bypass security
  81   // checks.
  82   NS_IMETHOD LoadBindingDocumentInfo(nsIContent* aBoundElement,
  83                                      nsIDocument* aBoundDocument,
  84                                      nsIURI* aBindingURI,
  85                                      nsIPrincipal* aOriginPrincipal,
  86                                      PRBool aForceSyncLoad,
  87                                      nsIXBLDocumentInfo** aResult);
  88
  89   // Used by XUL key bindings and for window XBL.
  90   NS_IMETHOD AttachGlobalKeyHandler(nsPIDOMEventTarget* aTarget);
  91   NS_IMETHOD DetachGlobalKeyHandler(nsPIDOMEventTarget* aTarget);
  92
  93   NS_DECL_NSIOBSERVER
  94
  95 public:
  96   nsXBLService();
  97   virtual ~nsXBLService();
  98
  99 protected:
 100   // This function clears out the bindings on a given content node.
 101   nsresult FlushStyleBindings(nsIContent* aContent);
 102
 103   // Release any memory that we can
 104   nsresult FlushMemory();
 105
 106   // This method synchronously loads and parses an XBL file.
 107   nsresult FetchBindingDocument(nsIContent* aBoundElement, nsIDocument* aBoundDocument,
 108                                 nsIURI* aDocumentURI, nsIURI* aBindingURI,
 109                                 PRBool aForceSyncLoad, nsIDocument** aResult);
 110
 111   nsIXBLDocumentInfo* GetXBLDocumentInfo(nsIURI* aURI,
 112                                          nsIContent* aBoundElement);
 113
 114   /**
 115    * This method calls the one below with an empty |aDontExtendURIs| array.
 116    */
 117   nsresult GetBinding(nsIContent* aBoundElement, nsIURI* aURI,
 118                       PRBool aPeekFlag, nsIPrincipal* aOriginPrincipal,
 119                       PRBool* aIsReady, nsXBLBinding** aResult);
 120
 121   /**
 122    * This method loads a binding doc and then builds the specific binding
 123    * required. It can also peek without building.
 124    * @param aBoundElement the element to get a binding for
 125    * @param aURI the binding URI
 126    * @param aPeekFlag if true then just peek to see if the binding is ready
 127    * @param aIsReady [out] if the binding is ready or not
 128    * @param aResult [out] where to store the resulting binding (not used if
 129    *                      aPeekFlag is true, otherwise it must be non-null)
 130    * @param aDontExtendURIs a set of URIs that are already bound to this
 131    *        element. If a binding extends any of these then further loading
 132    *        is aborted (because it would lead to the binding extending itself)
 133    *        and NS_ERROR_ILLEGAL_VALUE is returned.
 134    *
 135    * @note This method always calls LoadBindingDocumentInfo(), so it's
 136    *       enough to funnel all security checks through that function.
 137    */
 138   nsresult GetBinding(nsIContent* aBoundElement, nsIURI* aURI,
 139                       PRBool aPeekFlag, nsIPrincipal* aOriginPrincipal,
 140                       PRBool* aIsReady, nsXBLBinding** aResult,
 141                       nsTArray<nsIURI*>& aDontExtendURIs);
 142
 143 // MEMBER VARIABLES
 144 public:
 145   static PRUint32 gRefCnt;                   // A count of XBLservice instances.
 146
 147   static PRBool gDisableChromeCache;
 148
 149   static nsHashtable* gClassTable;           // A table of nsXBLJSClass objects.
 150
 151   static JSCList  gClassLRUList;             // LRU list of cached classes.
 152   static PRUint32 gClassLRUListLength;       // Number of classes on LRU list.
 153   static PRUint32 gClassLRUListQuota;        // Quota on class LRU list.
 154   static PRBool   gAllowDataURIs;            // Whether we should allow data
 155                                              // urls in -moz-binding. Needed for
 156                                              // testing.
 157
 158   nsFixedSizeAllocator mPool;
 159 };
 160
 161 class nsXBLJSClass : public JSCList, public JSClass
 162 {
 163 private:
 164   nsrefcnt mRefCnt;
 165   nsrefcnt Destroy();
 166
 167 public:
 168   nsXBLJSClass(const nsAFlatCString& aClassName);
 169   ~nsXBLJSClass() { nsMemory::Free((void*) name); }
 170
 171   nsrefcnt Hold() { return ++mRefCnt; }
 172   nsrefcnt Drop() { return --mRefCnt ? mRefCnt : Destroy(); }
 173 };
 174