Bug 378776, Need safe way to iterate a document's presshells, r+sr=bz

camino/src/embedding/CHClickListener.mm

@@ -1,265 +0,0 @@
-/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
-/* ***** BEGIN LICENSE BLOCK *****
- * Version: MPL 1.1/GPL 2.0/LGPL 2.1
- *
- * The contents of this file are subject to the Mozilla Public License Version
- * 1.1 (the "License"); you may not use this file except in compliance with
- * the License. You may obtain a copy of the License at
- * http://www.mozilla.org/MPL/
- *
- * Software distributed under the License is distributed on an "AS IS" basis,
- * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
- * for the specific language governing rights and limitations under the
- * License.
- *
- * The Original Code is mozilla.org code.
- *
- * The Initial Developer of the Original Code is
- * Netscape Communications Corporation.
- * Portions created by the Initial Developer are Copyright (C) 2002
- * the Initial Developer. All Rights Reserved.
- *
- * Contributor(s):
- *   David Hyatt <hyatt@mozilla.org> (Original Author)
- *
- * Alternatively, the contents of this file may be used under the terms of
- * either the GNU General Public License Version 2 or later (the "GPL"), or
- * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
- * in which case the provisions of the GPL or the LGPL are applicable instead
- * of those above. If you wish to allow use of your version of this file only
- * under the terms of either the GPL or the LGPL, and not to allow others to
- * use your version of this file under the terms of the MPL, indicate your
- * decision by deleting the provisions above and replace them with the notice
- * and other provisions required by the GPL or the LGPL. If you do not delete
- * the provisions above, a recipient may use your version of this file under
- * the terms of any one of the MPL, the GPL or the LGPL.
- *
- * ***** END LICENSE BLOCK ***** */
-
-#import "NSString+Utils.h"
-#import "NSArray+Utils.h"
-#import "CHBrowserView.h"
-
-#include "nsCOMPtr.h"
-#include "nsString.h"
-#include "CHClickListener.h"
-#include "nsIDOMEventTarget.h"
-#include "nsIContent.h"
-#include "nsIDOMElement.h"
-#include "nsIDOMMouseEvent.h"
-#include "nsEmbedAPI.h"
-#include "nsIDOMDocument.h"
-#include "nsIDOMDocumentEvent.h"
-#include "nsIDOMEventTarget.h"
-#include "nsIDOMHTMLSelectElement.h"
-#include "nsIDOMHTMLOptionElement.h"
-#include "nsIDOMHTMLOptionsCollection.h"
-#include "nsIDOMHTMLOptGroupElement.h"
-#include "nsIDOMWindow.h"
-#include "nsIDocument.h"
-#include "nsIPresShell.h"
-#include "nsIFrame.h"
-
-
-@interface CHOptionSelector : NSObject
-{
-  nsIDOMHTMLSelectElement* mSelectElt;
-}
-
--(id)initWithSelect:(nsIDOMHTMLSelectElement*)aSel;
--(IBAction)selectOption:(id)aSender;
-
-@end
-
-@implementation CHOptionSelector
-
--(id)initWithSelect:(nsIDOMHTMLSelectElement*)aSel
-{
-  if ( (self = [super init]) ) {
-    mSelectElt = aSel;
-  }
-  return self;
-}
-
--(IBAction)selectOption:(id)aSender
-{
-  nsIDOMHTMLOptionElement* optionElt = (nsIDOMHTMLOptionElement*)[[aSender representedObject] pointerValue];
-  NS_ASSERTION(optionElt, "Missing option element");
-  if (!optionElt) return;
-
-  optionElt->SetSelected(PR_TRUE);
-
-  // Fire a DOM event for the title change.
-  nsCOMPtr<nsIDOMEvent> event;
-  nsCOMPtr<nsIDOMDocument> domDocument;
-  mSelectElt->GetOwnerDocument(getter_AddRefs(domDocument));
-  nsCOMPtr<nsIDOMDocumentEvent> docEvent(do_QueryInterface(domDocument));
-  
-  docEvent->CreateEvent(NS_LITERAL_STRING("Events"), getter_AddRefs(event));
-  if (event) {
-    event->InitEvent(NS_LITERAL_STRING("change"), PR_TRUE, PR_TRUE);
-    PRBool noDefault;
-    nsCOMPtr<nsIDOMEventTarget> target(do_QueryInterface(mSelectElt));
-    target->DispatchEvent(event, &noDefault);
-  }  
-}
-
-@end
-
-NS_IMPL_ISUPPORTS2(CHClickListener, nsIDOMMouseListener, nsIDOMEventListener)
-
-CHClickListener::CHClickListener()
-{
-}
-
-CHClickListener::~CHClickListener()
-{
-}
-
-NS_IMETHODIMP
-CHClickListener::MouseDown(nsIDOMEvent* aEvent)
-{
-  nsCOMPtr<nsIDOMMouseEvent> mouseEvent(do_QueryInterface(aEvent));
-  if (!mouseEvent) return NS_ERROR_FAILURE;
-  
-  PRUint16 button;
-  mouseEvent->GetButton(&button);
-  // only show popup on left button
-  if (button != 0)
-    return NS_OK;
-
-  nsCOMPtr<nsIDOMEventTarget> target;
-  mouseEvent->GetTarget(getter_AddRefs(target));
-  if (!target)
-    return NS_OK;
-
-  nsCOMPtr<nsIDOMHTMLSelectElement> sel(do_QueryInterface(target));
-  if (!sel)
-    return NS_OK;
-
-  PRInt32 size = 0;
-  sel->GetSize(&size);
-  PRBool multiple = PR_FALSE;
-  sel->GetMultiple(&multiple);
-  if(size > 1 || multiple)
-    return NS_OK;
-
-  // the call to popUpContextMenu: is synchronous so we don't need to
-  // worry about retaining the menu for later.
-  NSMenu* menu = [[[NSMenu alloc] init] autorelease];
-
-  // We'll set the disabled state as the options are created, so disable
-  // auto-enabling via NSMenuValidation.
-  [menu setAutoenablesItems: NO];
-
-  nsCOMPtr<nsIDOMHTMLOptionsCollection> options;
-  sel->GetOptions(getter_AddRefs(options));
-  PRUint32 count;
-  options->GetLength(&count);
-  PRInt32 selIndex = 0;   // currently unused
-
-  nsCOMPtr<nsIDOMHTMLOptGroupElement> curOptGroup;
-
-  for (PRUint32 i = 0; i < count; i++) {
-    nsAutoString itemLabel;
-
-    nsCOMPtr<nsIDOMNode> node;
-    options->Item(i, getter_AddRefs(node));
-
-    nsCOMPtr<nsIDOMHTMLOptionElement> option(do_QueryInterface(node));
-
-    nsCOMPtr<nsIDOMNode> parentNode;
-    option->GetParentNode(getter_AddRefs(parentNode));
-    nsCOMPtr<nsIDOMHTMLOptGroupElement> parentOptGroup = do_QueryInterface(parentNode);
-    if (parentOptGroup && (parentOptGroup != curOptGroup))
-    {
-      // insert optgroup item
-      parentOptGroup->GetLabel(itemLabel);
-      NSString* title = [[NSString stringWith_nsAString: itemLabel] stringByTruncatingTo:75 at:kTruncateAtMiddle];
-      NSMenuItem* menuItem = [[[NSMenuItem alloc] initWithTitle: title action: NULL keyEquivalent: @""] autorelease];
-      [menu addItem: menuItem];
-      [menuItem setEnabled: NO];
-
-      curOptGroup = parentOptGroup;
-    }
-
-    option->GetLabel(itemLabel);
-    if (itemLabel.IsEmpty())
-      option->GetText(itemLabel);
-
-    NSString* title = [[NSString stringWith_nsAString: itemLabel] stringByTruncatingTo:75 at:kTruncateAtMiddle];
-    
-    // indent items in optgroup
-    if (parentOptGroup)
-      title = [@"  " stringByAppendingString:title];
-
-    NSMenuItem* menuItem = [[[NSMenuItem alloc] initWithTitle: title action: NULL keyEquivalent: @""] autorelease];
-    [menu addItem: menuItem];
-    [menuItem setRepresentedObject:[NSValue valueWithPointer:option.get()]];
-
-    PRBool selected;
-    option->GetSelected(&selected);
-    if (selected) {
-      [menuItem setState: NSOnState];
-      selIndex = i;
-    }
-    PRBool disabled;
-    option->GetDisabled(&disabled);
-    if (disabled)
-      [menuItem setEnabled: NO];
-    CHOptionSelector* optSelector = [[[CHOptionSelector alloc] initWithSelect: sel] autorelease];
-    [menuItem setTarget: optSelector];									// retains
-    if (!selected)
-      [menuItem setAction:@selector(selectOption:)];
-  }
-  
-  nsCOMPtr<nsIContent> selContent = do_QueryInterface(sel);
-  nsCOMPtr<nsIDocument> doc = selContent->GetDocument();
-
-  NSEvent*  event = [NSApp currentEvent];
-  NSWindow* hostWindow = [event window];
-  
-  // get the frame location
-  nsIPresShell* presShell = doc->GetShellAt(0);
-  if (!presShell)
-    return NS_ERROR_FAILURE;
-
-  nsIFrame* selectFrame = presShell->GetPrimaryFrameFor(selContent);
-  if (!selectFrame)
-    return NS_ERROR_FAILURE;
-  
-  nsIntRect selectRect = selectFrame->GetScreenRectExternal();
-  NSRect selectScreenRect = NSMakeRect(selectRect.x, selectRect.y, selectRect.width, selectRect.height);
-  
-  NSScreen* mainScreen = [[NSScreen screens] firstObject];  // NSArray category method
-  if (!mainScreen)
-    return NS_ERROR_FAILURE;
-
-  // y-flip and subtract the control height to convert to cocoa coords
-  NSRect mainScreenFrame = [mainScreen frame];
-  selectScreenRect.origin.y = NSMaxY(mainScreenFrame) - selectScreenRect.origin.y - selectScreenRect.size.height;
-
-  // convert to window coords
-  NSRect selectFrameRect = selectScreenRect;
-  selectFrameRect.origin = [hostWindow convertScreenToBase:selectFrameRect.origin];
-
-  // we're gonna make a little view to display things with, so that the popup isn't
-  // shown at the top of the window when it's near the bottom of the screen.
-  NSView* hostView = [[NSView alloc] initWithFrame:selectFrameRect];
-  [[hostWindow contentView] addSubview:hostView];   // takes ownership
-  [hostView release];
-
-  const float kMenuWidth = 20.0;               // specify something small so it sizes to fit
-  const float kMenuPopupHeight = 20.0;         // height of a popup in aqua
-
-  NSRect bounds = NSMakeRect(0, 0, kMenuWidth, kMenuPopupHeight);
-  
-  NSPopUpButtonCell* popupCell = [[NSPopUpButtonCell alloc] initTextCell:@"" pullsDown:NO];
-  [popupCell setMenu: menu];
-  [popupCell setFont:[NSFont systemFontOfSize:[NSFont systemFontSize]]];
-  [popupCell trackMouse:event inRect:bounds ofView:hostView untilMouseUp:YES];
-  [popupCell release];
-
-  [hostView removeFromSuperview];   // this releases it
-  return NS_OK;
-}

chrome/src/nsChromeRegistry.cpp

@@ -100,6 +100,7 @@
 #include "nsIXPConnect.h"
 #include "nsIXULAppInfo.h"
 #include "nsIXULRuntime.h"
+#include "nsPresShellIterator.h"
 
 #ifdef MOZ_XUL
 // keep all the RDF stuff together, in case we can remove it in the far future
@@ -923,10 +924,9 @@ nsresult nsChromeRegistry::RefreshWindow(nsIDOMWindowInternal* aWindow,
     return NS_OK;
 
   // Deal with the agent sheets first.  Have to do all the style sets by hand.
-  PRUint32 shellCount = document->GetNumberOfShells();
+  nsPresShellIterator iter(document);
-  for (PRUint32 k = 0; k < shellCount; k++) {
+  nsCOMPtr<nsIPresShell> shell;
-    nsIPresShell *shell = document->GetShellAt(k);
+  while ((shell = iter.GetNextShell())) {
-
     // Reload only the chrome URL agent style sheets.
     nsCOMArray<nsIStyleSheet> agentSheets;
     rv = shell->GetAgentStyleSheets(agentSheets);

content/base/public/Makefile.in

@@ -74,6 +74,7 @@ nsCopySupport.h \
 nsContentCreatorFunctions.h \
 nsLineBreaker.h \
 nsXMLNameSpaceMap.h \
+nsPresShellIterator.h \
 $(NULL)
 
 ifndef DISABLE_XFORMS_HOOKS

content/base/public/nsIDocument.h

@@ -49,6 +49,7 @@
 #include "mozFlushType.h"
 #include "nsIAtom.h"
 #include "nsCompatibility.h"
+#include "nsTObserverArray.h"
 
 class nsIContent;
 class nsPresContext;
@@ -94,8 +95,8 @@ class mozAutoSubtreeModified;
 
 // IID for the nsIDocument interface
 #define NS_IDOCUMENT_IID      \
-{ 0xb7f930df, 0x1c61, 0x410f, \
+{ 0x7dd5790f, 0x110d, 0x4bf6, \
- { 0xab, 0x3c, 0xe2, 0x53, 0xca, 0x8d, 0x85, 0x49 } }
+  { 0x83, 0x50, 0x4b, 0xe3, 0x5d, 0xdc, 0xe1, 0x1e } }
 
 // Flag for AddStyleSheet().
 #define NS_STYLESHEET_FROM_CATALOG                (1 << 0)
@@ -349,10 +350,9 @@ public:
                                nsStyleSet* aStyleSet,
                                nsIPresShell** aInstancePtrResult) = 0;
   virtual PRBool DeleteShell(nsIPresShell* aShell) = 0;
-  virtual PRUint32 GetNumberOfShells() const = 0;
-  virtual nsIPresShell *GetShellAt(PRUint32 aIndex) const = 0;
   virtual nsIPresShell *GetPrimaryShell() const = 0;
-  virtual void SetShellsHidden(PRBool aHide) = 0;
+  void SetShellsHidden(PRBool aHide) { mShellsAreHidden = aHide; }
+  PRBool ShellsAreHidden() const { return mShellsAreHidden; }
 
   /**
    * Return the parent document of this document. Will return null
@@ -891,6 +891,7 @@ protected:
   virtual void WillDispatchMutationEvent(nsINode* aTarget) = 0;
   virtual void MutationEventDispatched(nsINode* aTarget) = 0;
   friend class mozAutoSubtreeModified;
+  friend class nsPresShellIterator;
 
   nsString mDocumentTitle;
   nsCOMPtr<nsIURI> mDocumentURI;
@@ -932,6 +933,8 @@ protected:
   // document in it.
   PRPackedBool mIsInitialDocumentInWindow;
 
+  PRPackedBool mShellsAreHidden;
+
   // The bidi options for this document.  What this bitfield means is
   // defined in nsBidiUtils.h
   PRUint32 mBidiOptions;
@@ -949,6 +952,8 @@ protected:
   // Cycle collector generation in which we're certain that this document
   // won't be collected
   PRUint32 mMarkedCCGeneration;
+
+  nsTObserverArray<nsIPresShell> mPresShells;
 };
 
 NS_DEFINE_STATIC_IID_ACCESSOR(nsIDocument, NS_IDOCUMENT_IID)

content/base/public/nsPresShellIterator.h

@@ -0,0 +1,68 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is mozilla.org code.
+ *
+ * The Initial Developer of the Original Code is Mozilla Foundation.
+ * Portions created by the Initial Developer are Copyright (C) 2007
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *   Olli Pettay <Olli.Pettay@helsinki.fi> (Original Author)
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either of the GNU General Public License Version 2 or later (the "GPL"),
+ * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+#ifndef nsPresShellIterato_h___
+#define nsPresShellIterato_h___
+
+#include "nsIPresShell.h"
+#include "nsIDocument.h"
+
+class nsPresShellIterator :
+  private nsTObserverArray<nsIPresShell>::ForwardIterator
+{
+public:
+  nsPresShellIterator(nsIDocument* aDoc)
+  : nsTObserverArray<nsIPresShell>::ForwardIterator(aDoc->mPresShells),
+    mDoc(aDoc) {}
+
+  already_AddRefed<nsIPresShell> GetNextShell()
+  {
+    nsIPresShell* shell = nsnull;
+    if (!mDoc->ShellsAreHidden()) {
+      shell = GetNext();
+      NS_IF_ADDREF(shell);
+    }
+    return shell;
+  }
+private:
+  static void* operator new(size_t) CPP_THROW_NEW { return 0; }
+  static void operator delete(void*, size_t) {}
+
+  nsCOMPtr<nsIDocument> mDoc;
+};
+
+#endif

content/base/src/nsContentSink.cpp

@@ -91,6 +91,7 @@
 #include "nsNodeUtils.h"
 #include "nsIDOMNode.h"
 #include "nsThreadUtils.h"
+#include "nsPresShellIterator.h"
 
 PRLogModuleInfo* gContentSinkLogModuleInfo;
 
@@ -949,10 +950,9 @@ nsContentSink::ScrollToRef()
   // http://www.w3.org/TR/html4/appendix/notes.html#h-B.2.1
   NS_ConvertUTF8toUTF16 ref(unescapedRef);
 
-  PRInt32 i, ns = mDocument->GetNumberOfShells();
+  nsPresShellIterator iter(mDocument);
-  for (i = 0; i < ns; i++) {
+  nsCOMPtr<nsIPresShell> shell;
-    nsIPresShell* shell = mDocument->GetShellAt(i);
+  while ((shell = iter.GetNextShell())) {
-    if (shell) {
     // Check an empty string which might be caused by the UTF-8 conversion
     if (!ref.IsEmpty()) {
       // Note that GoToAnchor will handle flushing layout as needed.
@@ -977,7 +977,6 @@ nsContentSink::ScrollToRef()
     }
   }
 }
-}
 
 nsresult
 nsContentSink::RefreshIfEnabled(nsIViewManager* vm)
@@ -1030,14 +1029,9 @@ nsContentSink::StartLayout(PRBool aIgnorePendingSheets)
   mLayoutStarted = PR_TRUE;
   mLastNotificationTime = PR_Now();
 
-  PRUint32 i;
+  nsPresShellIterator iter(mDocument);
-
+  nsCOMPtr<nsIPresShell> shell;
-  // XXXbz Shells can get removed (or added!) as we iterate through this loop.
+  while ((shell = iter.GetNextShell())) {
-  // We should try to use an nsTObserverArray for this.
-  for (i = 0; i < mDocument->GetNumberOfShells(); i++) {
-    nsIPresShell *shell = mDocument->GetShellAt(i);
-
-    if (shell) {
     // Make sure we don't call InitialReflow() for a shell that has
     // already called it. This can happen when the layout frame for
     // an iframe is constructed *between* the Embed() call for the
@@ -1069,7 +1063,6 @@ nsContentSink::StartLayout(PRBool aIgnorePendingSheets)
     // Now trigger a refresh
     RefreshIfEnabled(shell->GetViewManager());
   }
-  }
 
   // If the document we are loading has a reference or it is a
   // frameset document, disable the scroll bars on the views.

content/base/src/nsDocument.cpp

@@ -1294,9 +1294,10 @@ nsDocument::ResetStylesheetsToURI(nsIURI* aURI)
     PRBool applicable;
     sheet->GetApplicable(applicable);
     if (applicable) {
-      for (PRInt32 i = 0, i_end = GetNumberOfShells(); i < i_end; ++i) {
+      nsPresShellIterator iter(this);
-        GetShellAt(i)->StyleSet()->
+      nsCOMPtr<nsIPresShell> shell;
-          RemoveStyleSheet(nsStyleSet::eAgentSheet, sheet);
+      while ((shell = iter.GetNextShell())) {
+        shell->StyleSet()->RemoveStyleSheet(nsStyleSet::eAgentSheet, sheet);
       }
     }
 
@@ -1315,10 +1316,10 @@ nsDocument::ResetStylesheetsToURI(nsIURI* aURI)
   nsStyleSet::sheetType attrSheetType = GetAttrSheetType();
   if (mAttrStyleSheet) {
     // Remove this sheet from all style sets
-    PRInt32 count = GetNumberOfShells();
+    nsPresShellIterator iter(this);
-    for (indx = 0; indx < count; ++indx) {
+    nsCOMPtr<nsIPresShell> shell;
-      GetShellAt(indx)->StyleSet()->
+    while ((shell = iter.GetNextShell())) {
-        RemoveStyleSheet(attrSheetType, mAttrStyleSheet);
+      shell->StyleSet()->RemoveStyleSheet(attrSheetType, mAttrStyleSheet);
     }
     rv = mAttrStyleSheet->Reset(aURI);
   } else {
@@ -1332,9 +1333,10 @@ nsDocument::ResetStylesheetsToURI(nsIURI* aURI)
   
   if (mStyleAttrStyleSheet) {
     // Remove this sheet from all style sets
-    PRInt32 count = GetNumberOfShells();
+    nsPresShellIterator iter(this);
-    for (indx = 0; indx < count; ++indx) {
+    nsCOMPtr<nsIPresShell> shell;
-      GetShellAt(indx)->StyleSet()->
+    while ((shell = iter.GetNextShell())) {
+      shell->StyleSet()->
         RemoveStyleSheet(nsStyleSet::eStyleAttrSheet, mStyleAttrStyleSheet);
     }
     rv = mStyleAttrStyleSheet->Reset(aURI);
@@ -1349,9 +1351,10 @@ nsDocument::ResetStylesheetsToURI(nsIURI* aURI)
   mStyleAttrStyleSheet->SetOwningDocument(this);
 
   // Now set up our style sets
-  PRInt32 count = GetNumberOfShells();
+  nsPresShellIterator iter(this);
-  for (indx = 0; indx < count; ++indx) {
+  nsCOMPtr<nsIPresShell> shell;
-    FillStyleSet(GetShellAt(indx)->StyleSet());
+  while ((shell = iter.GetNextShell())) {
+    FillStyleSet(shell->StyleSet());
   }
 
   return rv;
@@ -1950,7 +1953,7 @@ nsDocument::doCreateShell(nsPresContext* aContext,
   NS_ENSURE_SUCCESS(rv, rv);
 
   // Note: we don't hold a ref to the shell (it holds a ref to us)
-  mPresShells.AppendElement(shell);
+  NS_ENSURE_TRUE(mPresShells.AppendObserver(shell), NS_ERROR_OUT_OF_MEMORY);
   shell.swap(*aInstancePtrResult);
 
   return NS_OK;
@@ -1959,33 +1962,14 @@ nsDocument::doCreateShell(nsPresContext* aContext,
 PRBool
 nsDocument::DeleteShell(nsIPresShell* aShell)
 {
-  return mPresShells.RemoveElement(aShell);
+  return mPresShells.RemoveObserver(aShell);
 }
 
-PRUint32
-nsDocument::GetNumberOfShells() const
-{
-  return mShellsAreHidden ? 0 : mPresShells.Count();
-}
-
-nsIPresShell *
-nsDocument::GetShellAt(PRUint32 aIndex) const
-{
-  return mShellsAreHidden ? nsnull :
-         NS_STATIC_CAST(nsIPresShell*, mPresShells.SafeElementAt(aIndex));
-}
 
 nsIPresShell *
 nsDocument::GetPrimaryShell() const
 {
-  return mShellsAreHidden ? nsnull :
+  return mShellsAreHidden ? nsnull : mPresShells.SafeObserverAt(0);
-         NS_STATIC_CAST(nsIPresShell*, mPresShells.SafeElementAt(0));
-}
-
-void
-nsDocument::SetShellsHidden(PRBool aHide)
-{
-  mShellsAreHidden = aHide;
 }
 
 PR_STATIC_CALLBACK(void)
@@ -2279,10 +2263,10 @@ nsDocument::GetIndexOfStyleSheet(nsIStyleSheet* aSheet) const
 void
 nsDocument::AddStyleSheetToStyleSets(nsIStyleSheet* aSheet)
 {
-  PRInt32 count = GetNumberOfShells();
+  nsPresShellIterator iter(this);
-  PRInt32 indx;
+  nsCOMPtr<nsIPresShell> shell;
-  for (indx = 0; indx < count; ++indx) {
+  while ((shell = iter.GetNextShell())) {
-    GetShellAt(indx)->StyleSet()->AddDocStyleSheet(aSheet, this);
+    shell->StyleSet()->AddDocStyleSheet(aSheet, this);
   }
 }
 
@@ -2306,9 +2290,11 @@ nsDocument::AddStyleSheet(nsIStyleSheet* aSheet)
 void
 nsDocument::RemoveStyleSheetFromStyleSets(nsIStyleSheet* aSheet)
 {
-  for (PRInt32 i = 0, i_end = GetNumberOfShells(); i < i_end; ++i)
+  nsPresShellIterator iter(this);
-    GetShellAt(i)->StyleSet()->
+  nsCOMPtr<nsIPresShell> shell;
-      RemoveStyleSheet(nsStyleSet::eDocSheet, aSheet);
+  while ((shell = iter.GetNextShell())) {
+    shell->StyleSet()->RemoveStyleSheet(nsStyleSet::eDocSheet, aSheet);
+  }
 }
 
 void
@@ -2443,9 +2429,11 @@ nsDocument::AddCatalogStyleSheet(nsIStyleSheet* aSheet)
                                                                                 
   if (applicable) {
     // This is like |AddStyleSheetToStyleSets|, but for an agent sheet.
-    for (PRInt32 i = 0, i_end = GetNumberOfShells(); i < i_end; ++i)
+    nsPresShellIterator iter(this);
-      GetShellAt(i)->StyleSet()->
+    nsCOMPtr<nsIPresShell> shell;
-        AppendStyleSheet(nsStyleSet::eAgentSheet, aSheet);
+    while ((shell = iter.GetNextShell())) {
+      shell->StyleSet()->AppendStyleSheet(nsStyleSet::eAgentSheet, aSheet);
+    }
   }
                                                                                 
   NS_DOCUMENT_NOTIFY_OBSERVERS(StyleSheetAdded, (this, aSheet, PR_FALSE));
@@ -3633,9 +3621,9 @@ nsDocument::GetTitle(nsAString& aTitle)
 NS_IMETHODIMP
 nsDocument::SetTitle(const nsAString& aTitle)
 {
-  for (PRInt32 i = GetNumberOfShells() - 1; i >= 0; --i) {
+  nsPresShellIterator iter(this);
-    nsCOMPtr<nsIPresShell> shell = GetShellAt(i);
+  nsCOMPtr<nsIPresShell> shell;
-
+  while ((shell = iter.GetNextShell())) {
     nsCOMPtr<nsISupports> container = shell->GetPresContext()->GetContainer();
     if (!container)
       continue;
@@ -4805,16 +4793,12 @@ nsDocument::FlushPendingNotifications(mozFlushType aType)
     }
   }
 
-  PRInt32 i, count = GetNumberOfShells();
+  nsPresShellIterator iter(this);
-
+  nsCOMPtr<nsIPresShell> shell;
-  for (i = 0; i < count; i++) {
+  while ((shell = iter.GetNextShell())) {
-    nsCOMPtr<nsIPresShell> shell = GetShellAt(i);
-
-    if (shell) {
     shell->FlushPendingNotifications(aType);
   }
 }
-}
 
 void
 nsDocument::AddReference(void *aKey, nsISupports *aReference)
@@ -5261,15 +5245,12 @@ PRBool
 nsDocument::IsSafeToFlush() const
 {
   PRBool isSafeToFlush = PR_TRUE;
-  PRInt32 i = 0, n = GetNumberOfShells();
+  nsPresShellIterator iter(NS_CONST_CAST(nsIDocument*,
-  while (i < n && isSafeToFlush) {
+                           NS_STATIC_CAST(const nsIDocument*, this)));
-    nsIPresShell* shell = GetShellAt(i);
+  nsCOMPtr<nsIPresShell> shell;
-
+  while ((shell = iter.GetNextShell()) && isSafeToFlush) {
-    if (shell) {
     shell->IsSafeToFlush(isSafeToFlush);
   }
-    ++i;
-  }
   return isSafeToFlush;
 }
 

content/base/src/nsDocument.h

@@ -101,6 +101,7 @@
 #include "pldhash.h"
 #include "nsAttrAndChildArray.h"
 #include "nsDOMAttributeMap.h"
+#include "nsPresShellIterator.h"
 
 #define XML_DECLARATION_BITS_DECLARATION_EXISTS   (1 << 0)
 #define XML_DECLARATION_BITS_ENCODING_EXISTS      (1 << 1)
@@ -374,10 +375,7 @@ public:
                                nsStyleSet* aStyleSet,
                                nsIPresShell** aInstancePtrResult);
   virtual PRBool DeleteShell(nsIPresShell* aShell);
-  virtual PRUint32 GetNumberOfShells() const;
-  virtual nsIPresShell *GetShellAt(PRUint32 aIndex) const;
   virtual nsIPresShell *GetPrimaryShell() const;
-  virtual void SetShellsHidden(PRBool aHide);
 
   virtual nsresult SetSubDocumentFor(nsIContent *aContent,
                                      nsIDocument* aSubDoc);
@@ -765,8 +763,6 @@ protected:
   // True if the document "page" is not hidden
   PRPackedBool mVisible:1;
 
-  PRPackedBool mShellsAreHidden:1;
-
   PRUint8 mXMLDeclarationBits;
 
   PRUint8 mDefaultElementType;
@@ -807,8 +803,6 @@ private:
   nsDocument(const nsDocument& aOther);
   nsDocument& operator=(const nsDocument& aOther);
 
-  nsSmallVoidArray mPresShells;
-
   nsCOMPtr<nsISupports> mXPathEvaluatorTearoff;
 
   // The layout history state that should be used by nodes in this

content/base/src/nsObjectLoadingContent.cpp

@@ -74,6 +74,7 @@
 #include "nsGkAtoms.h"
 #include "nsThreadUtils.h"
 #include "nsNetUtil.h"
+#include "nsPresShellIterator.h"
 
 // Concrete classes
 #include "nsFrameLoader.h"
@@ -543,9 +544,9 @@ nsObjectLoadingContent::EnsureInstantiation(nsIPluginInstance** aInstance)
       return NS_OK;
     }
 
-    PRUint32 numShells = doc->GetNumberOfShells();
+    nsPresShellIterator iter(doc);
-    for (PRUint32 i = 0; i < numShells; ++i) {
+    nsCOMPtr<nsIPresShell> shell;
-      nsIPresShell* shell = doc->GetShellAt(i);
+    while ((shell = iter.GetNextShell())) {
       shell->RecreateFramesFor(thisContent);
     }
 
@@ -1175,9 +1176,9 @@ nsObjectLoadingContent::NotifyStateChanged(ObjectType aOldType,
     // If our state changed, then we already recreated frames
     // Otherwise, need to do that here
 
-    PRUint32 numShells = doc->GetNumberOfShells();
+    nsPresShellIterator iter(doc);
-    for (PRUint32 i = 0; i < numShells; ++i) {
+    nsCOMPtr<nsIPresShell> shell;
-      nsIPresShell* shell = doc->GetShellAt(i);
+    while ((shell = iter.GetNextShell())) {
       shell->RecreateFramesFor(thisContent);
     }
   }

content/events/src/nsEventStateManager.cpp

@@ -131,6 +131,7 @@
 #include "nsIProperties.h"
 #include "nsISupportsPrimitives.h"
 #include "nsEventDispatcher.h"
+#include "nsPresShellIterator.h"
 
 #ifdef XP_MACOSX
 #include <Events.h>
@@ -1987,9 +1988,9 @@ nsEventStateManager::GetParentScrollingView(nsInputEvent *aEvent,
   }
 
   nsIPresShell *pPresShell = nsnull;
-  for (PRUint32 i = 0; i < parentDoc->GetNumberOfShells(); i++) {
+  nsPresShellIterator iter(parentDoc);
-    nsIPresShell *tmpPresShell = parentDoc->GetShellAt(i);
+  nsCOMPtr<nsIPresShell> tmpPresShell;
-    NS_ENSURE_TRUE(tmpPresShell, NS_ERROR_FAILURE);
+  while ((tmpPresShell = iter.GetNextShell())) {
     NS_ENSURE_TRUE(tmpPresShell->GetPresContext(), NS_ERROR_FAILURE);
     if (tmpPresShell->GetPresContext()->Type() == aPresContext->Type()) {
       pPresShell = tmpPresShell;

content/html/document/src/nsHTMLDocument.cpp

@@ -2352,7 +2352,7 @@ nsHTMLDocument::Close()
     // it be for now, though.  In any case, there's no reason to do
     // this if we have no presshell, since in that case none of the
     // above about reusing frames applies.
-    if (GetNumberOfShells() != 0) {
+    if (GetPrimaryShell()) {
       FlushPendingNotifications(Flush_Layout);
     }
 

content/html/document/src/nsMediaDocument.cpp

@@ -266,12 +266,9 @@ nsMediaDocument::CreateSyntheticDocument()
 nsresult
 nsMediaDocument::StartLayout()
 {
-  PRUint32 numberOfShells = GetNumberOfShells();
+  nsPresShellIterator iter(this);
-  // XXXbz Shells can get removed (or added!) as we iterate through this loop.
+  nsCOMPtr<nsIPresShell> shell;
-  // We should try to use an nsTObserverArray for this.
+  while ((shell = iter.GetNextShell())) {
-  for (PRUint32 i = 0; i < numberOfShells; i++) {
-    nsIPresShell *shell = GetShellAt(i);
-
     // Make shell an observer for next time.
     shell->BeginObservingDocument();
 

content/xml/document/src/nsXMLPrettyPrinter.cpp

@@ -74,7 +74,7 @@ nsresult
 nsXMLPrettyPrinter::PrettyPrint(nsIDocument* aDocument)
 {
     // Check for iframe with display:none. Such iframes don't have presshells
-    if (!aDocument->GetNumberOfShells()) {
+    if (!aDocument->GetPrimaryShell()) {
         return NS_OK;
     }
 

content/xul/content/src/nsXULElement.cpp

@@ -150,6 +150,7 @@
 #include "nsNodeInfoManager.h"
 #include "nsXBLBinding.h"
 #include "nsEventDispatcher.h"
+#include "nsPresShellIterator.h"
 
 /**
  * Three bits are used for XUL Element's lazy state.
@@ -1889,10 +1890,10 @@ nsXULElement::Focus()
         return NS_OK;
 
     // Obtain a presentation context and then call SetFocus.
-    if (doc->GetNumberOfShells() == 0)
-        return NS_OK;
 
     nsIPresShell *shell = doc->GetPrimaryShell();
+    if (!shell)
+        return NS_OK;
 
     // Set focus
     nsCOMPtr<nsPresContext> context = shell->GetPresContext();
@@ -1910,10 +1911,9 @@ nsXULElement::Blur()
         return NS_OK;
 
     // Obtain a presentation context and then call SetFocus.
-    if (doc->GetNumberOfShells() == 0)
-        return NS_OK;
-
     nsIPresShell *shell = doc->GetPrimaryShell();
+    if (!shell)
+        return NS_OK;
 
     // Set focus
     nsCOMPtr<nsPresContext> context = shell->GetPresContext();
@@ -1931,13 +1931,11 @@ nsXULElement::Click()
 
     nsCOMPtr<nsIDocument> doc = GetCurrentDoc(); // Strong just in case
     if (doc) {
-        PRUint32 numShells = doc->GetNumberOfShells();
+        nsPresShellIterator iter(doc);
+        nsCOMPtr<nsIPresShell> shell;
+        while ((shell = iter.GetNextShell())) {
             // strong ref to PresContext so events don't destroy it
-        nsCOMPtr<nsPresContext> context;
+            nsCOMPtr<nsPresContext> context = shell->GetPresContext();
-
-        for (PRUint32 i = 0; i < numShells; ++i) {
-            nsIPresShell *shell = doc->GetShellAt(i);
-            context = shell->GetPresContext();
 
             PRBool isCallerChrome = nsContentUtils::IsCallerChrome();
 
@@ -1974,13 +1972,10 @@ nsXULElement::DoCommand()
 {
     nsCOMPtr<nsIDocument> doc = GetCurrentDoc(); // strong just in case
     if (doc) {
-        PRUint32 numShells = doc->GetNumberOfShells();
+        nsPresShellIterator iter(doc);
-        nsCOMPtr<nsPresContext> context;
+        nsCOMPtr<nsIPresShell> shell;
-
+        while ((shell = iter.GetNextShell())) {
-        for (PRUint32 i = 0; i < numShells; ++i) {
+            nsCOMPtr<nsPresContext> context = shell->GetPresContext();
-            nsIPresShell *shell = doc->GetShellAt(i);
-            context = shell->GetPresContext();
-
             nsEventStatus status = nsEventStatus_eIgnore;
             nsXULCommandEvent event(PR_TRUE, NS_XUL_COMMAND, nsnull);
             nsEventDispatcher::Dispatch(NS_STATIC_CAST(nsIContent*, this),

content/xul/document/src/nsXULCommandDispatcher.cpp

@@ -69,6 +69,7 @@
 #include "nsCRT.h"
 #include "nsDOMError.h"
 #include "nsEventDispatcher.h"
+#include "nsPresShellIterator.h"
 
 #ifdef PR_LOGGING
 static PRLogModuleInfo* gLog;
@@ -391,9 +392,9 @@ nsXULCommandDispatcher::UpdateCommands(const nsAString& aEventName)
     }
 #endif
 
-    PRUint32 count = document->GetNumberOfShells();
+    nsPresShellIterator iter(document);
-    for (PRUint32 i = 0; i < count; i++) {
+    nsCOMPtr<nsIPresShell> shell;
-      nsIPresShell *shell = document->GetShellAt(i);
+    while ((shell = iter.GetNextShell())) {
 
       // Retrieve the context in which our DOM event will fire.
       nsCOMPtr<nsPresContext> context = shell->GetPresContext();

content/xul/document/src/nsXULDocument.cpp

@@ -901,9 +901,9 @@ nsXULDocument::ExecuteOnBroadcastHandlerFor(nsIContent* aBroadcaster,
         // |onbroadcast| event handler
         nsEvent event(PR_TRUE, NS_XUL_BROADCAST);
 
-        PRInt32 j = GetNumberOfShells();
+        nsPresShellIterator iter(this);
-        while (--j >= 0) {
+        nsCOMPtr<nsIPresShell> shell;
-            nsCOMPtr<nsIPresShell> shell = GetShellAt(j);
+        while ((shell = iter.GetNextShell())) {
 
             nsCOMPtr<nsPresContext> aPresContext = shell->GetPresContext();
 
@@ -1973,10 +1973,9 @@ nsXULDocument::StartLayout(void)
         return NS_OK;
     }
 
-    // XXXbz Shells can get removed (or added!) as we iterate through this
+    nsPresShellIterator iter(this);
-    // loop.  We should try to use an nsTObserverArray for this.
+    nsCOMPtr<nsIPresShell> shell;
-    for (PRUint32 i = 0; i < GetNumberOfShells(); ++i) {
+    while ((shell = iter.GetNextShell())) {
-        nsIPresShell *shell = GetShellAt(i);
 
         // Resize-reflow this time
         nsPresContext *cx = shell->GetPresContext();

dom/src/base/nsFocusController.cpp

@@ -211,7 +211,7 @@ nsFocusController::UpdateCommands()
   }
 
   // If there is no presshell, it's a zombie document which can't handle the command updates
-  if (window && doc && doc->GetNumberOfShells()) {
+  if (window && doc && doc->GetPrimaryShell()) {
     // Not a zombie document, so we can handle the command update
     window->UpdateCommands(NS_LITERAL_STRING("focus"));
     mNeedUpdateCommands = PR_FALSE;
@@ -283,10 +283,6 @@ nsFocusController::MoveFocus(PRBool aForward, nsIDOMElement* aElt)
 
 
   // Obtain a presentation context
-  PRInt32 count = doc->GetNumberOfShells();
-  if (count == 0)
-    return NS_OK;
-
   nsIPresShell *shell = doc->GetPrimaryShell();
   if (!shell)
     return NS_OK;

extensions/typeaheadfind/src/nsTypeAheadFind.cpp

@@ -101,6 +101,7 @@
 #include "nsIDOMEventTarget.h"
 #include "nsIDOM3EventTarget.h"
 #include "nsIDOMEventGroup.h"
+#include "nsPresShellIterator.h"
 
 // Header for this class
 #include "nsTypeAheadFind.h"
@@ -554,11 +555,11 @@ nsTypeAheadFind::HandleEvent(nsIDOMEvent* aEvent)
       return NS_ERROR_FAILURE;
     }
 
-    PRUint32 numShells = doc->GetNumberOfShells();
     PRBool cancelFind = PR_FALSE;
 
-    for (PRUint32 count = 0; count < numShells; count ++) {
+    nsPresShellIterator iter(doc);
-      nsIPresShell *shellToBeDestroyed = doc->GetShellAt(count);
+    nsCOMPtr<nsIPresShell> shellToBeDestroyed;
+    while ((shellToBeDestroyed = iter.GetNextShell())) {
       if (shellToBeDestroyed == focusedShell) {
         cancelFind = PR_TRUE;
         break;

layout/svg/base/src/nsSVGOuterSVGFrame.cpp

@@ -44,6 +44,7 @@
 #include "nsDisplayList.h"
 #include "nsStubMutationObserver.h"
 #include "gfxContext.h"
+#include "nsPresShellIterator.h"
 
 #if defined(DEBUG) && defined(SVG_DEBUG_PRINTING)
 #include "nsIDeviceContext.h"
@@ -88,9 +89,10 @@ nsSVGMutationObserver::AttributeChanged(nsIDocument *aDocument,
     return;
   }
 
-  PRUint32 count = aDocument->GetNumberOfShells();
+  nsPresShellIterator iter(aDocument);
-  for (PRUint32 i = 0; i < count; ++i) {
+  nsCOMPtr<nsIPresShell> shell;
-    nsIFrame *frame = aDocument->GetShellAt(i)->GetPrimaryFrameFor(aContent);
+  while ((shell = iter.GetNextShell())) {
+    nsIFrame *frame = shell->GetPrimaryFrameFor(aContent);
     if (!frame) {
       continue;
     }

rdf/chrome/src/nsChromeRegistry.cpp

@@ -94,6 +94,7 @@
 #include "nsIJARURI.h"
 #include "nsIFileURL.h"
 #include "nsIXPConnect.h"
+#include "nsPresShellIterator.h"
 
 static char kChromePrefix[] = "chrome://";
 nsIAtom* nsChromeRegistry::sCPrefix; // atom for "c"
@@ -1396,10 +1397,9 @@ nsresult nsChromeRegistry::RefreshWindow(nsIDOMWindowInternal* aWindow)
     return NS_OK;
 
   // Deal with the agent sheets first.  Have to do all the style sets by hand.
-  PRUint32 shellCount = document->GetNumberOfShells();
+  nsPresShellIterator iter(document);
-  for (PRUint32 k = 0; k < shellCount; k++) {
+  nsCOMPtr<nsIPresShell> shell;
-    nsIPresShell *shell = document->GetShellAt(k);
+  while ((shell = iter.GetNextShell())) {
-
     // Reload only the chrome URL agent style sheets.
     nsCOMArray<nsIStyleSheet> agentSheets;
     rv = shell->GetAgentStyleSheets(agentSheets);