Added get/set document state API for use by session history.

layout/base/nsILayoutHistoryState.h

@@ -0,0 +1,25 @@
+#ifndef _nsILayoutHistoryState_h
+#define _nsILayoutHistoryState_h
+
+#include "nsISupports.h"
+
+#define NS_ILAYOUTHISTORYSTATE_IID_STR "306c8ca0-5f0c-11d3-a9fb-000064657374"
+
+#define NS_ILAYOUTHISTORYSTATE_IID \
+{0x306c8ca0, 0x5f0c, 0x11d3, \
+{0xa9, 0xfb, 0x00, 0x00, 0x64, 0x65, 0x73, 0x74}}
+
+#define NS_HISTORY_STATE_TYPE_NONE -1
+
+class nsILayoutHistoryState : public nsISupports {
+ public: 
+  NS_DEFINE_STATIC_IID_ACCESSOR(NS_ILAYOUTHISTORYSTATE_IID)
+
+  NS_IMETHOD AddState(PRUint32 aContentID, nsISupports* aState, PRInt32 aStateType) = 0;
+  NS_IMETHOD GetState(PRUint32 aContentID, nsISupports** aState, PRInt32 aStateType) = 0;
+};
+
+nsresult
+NS_NewLayoutHistoryState(nsILayoutHistoryState** aState);
+
+#endif /* _nsILayoutHistoryState_h */

layout/base/nsIPresShell.h

@@ -40,6 +40,7 @@ class nsICaret;
 class nsIStyleContext;
 class nsIFrameSelection;
 class nsIFrameManager;
+class nsILayoutHistoryState;
 
 #define NS_IPRESSHELL_IID     \
 { 0x76e79c60, 0x944e, 0x11d1, \
@@ -336,6 +337,18 @@ public:
 
   // XXX events
   // XXX selection
+  
+  /**
+   * Get the history state for the current document 
+   */
+  NS_IMETHOD GetHistoryState(nsILayoutHistoryState** aLayoutHistoryState) = 0;
+
+  /**
+   * Capture frame state for the frame subtree rooted at aFrame.
+   * aState is the document state storage object onto which each frame 
+   * stores its state.
+   */
+  NS_IMETHOD CaptureFrameState(nsIFrame* aFrame, nsILayoutHistoryState* aState) = 0;
 
   /**
    * See if reflow verification is enabled. To enable reflow verification add
@@ -349,6 +362,7 @@ public:
    * Set the verify-reflow enable flag.
    */
   static NS_LAYOUT void SetVerifyReflowEnable(PRBool aEnabled);
+
 };
 
 /**

layout/base/nsLayoutHistoryState.cpp

@@ -0,0 +1,87 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ *
+ * The contents of this file are subject to the Netscape Public License
+ * Version 1.0 (the "NPL"); you may not use this file except in
+ * compliance with the NPL.  You may obtain a copy of the NPL at
+ * http://www.mozilla.org/NPL/
+ *
+ * Software distributed under the NPL is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
+ * for the specific language governing rights and limitations under the
+ * NPL.
+ *
+ * The Initial Developer of this code under the NPL is Netscape
+ * Communications Corporation.  Portions created by Netscape are
+ * Copyright (C) 1998 Netscape Communications Corporation.  All Rights
+ * Reserved.
+ */
+
+#include "nsILayoutHistoryState.h"
+#include "nsHashtable.h"
+
+class nsLayoutHistoryState : public nsILayoutHistoryState
+{
+public:
+  nsLayoutHistoryState();
+  virtual ~nsLayoutHistoryState();
+
+  NS_DECL_ISUPPORTS
+
+  // nsILayoutHistoryState
+  NS_IMETHOD AddState(PRUint32 aContentID,
+    nsISupports* aState,
+    PRInt32 aStateType = NS_HISTORY_STATE_TYPE_NONE);
+  NS_IMETHOD GetState(PRUint32 aContentID,
+    nsISupports** aState,
+    PRInt32 aStateType = NS_HISTORY_STATE_TYPE_NONE);
+
+private:
+  nsSupportsHashtable mStates;
+};
+
+nsresult
+NS_NewLayoutHistoryState(nsILayoutHistoryState** aState)
+{
+    NS_PRECONDITION(aState != nsnull, "null ptr");
+    if (! aState)
+        return NS_ERROR_NULL_POINTER;
+
+    *aState = new nsLayoutHistoryState();
+    if (! *aState)
+        return NS_ERROR_OUT_OF_MEMORY;
+
+    NS_ADDREF(*aState);
+
+    return NS_OK;
+}
+
+nsLayoutHistoryState::nsLayoutHistoryState()
+{
+  NS_INIT_REFCNT();
+  
+
+}
+
+nsLayoutHistoryState::~nsLayoutHistoryState()
+{
+
+}
+
+NS_IMPL_ISUPPORTS(nsLayoutHistoryState, 
+                  nsILayoutHistoryState::GetIID());
+
+NS_IMETHODIMP
+nsLayoutHistoryState::AddState(PRUint32 aContentID,                                
+                               nsISupports* aState, 
+                               PRInt32 aStateType)
+{
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsLayoutHistoryState::GetState(PRUint32 aContentID,                                
+                               nsISupports** aState,
+                               PRInt32 aStateType)
+{
+  return NS_OK;
+}

layout/base/nsPresShell.cpp

@@ -62,6 +62,8 @@
 #include "nsViewsCID.h"
 #include "nsIFrameManager.h"
 #include "nsISupportsPrimitives.h"
+#include "nsILayoutHistoryState.h"
+#include "nsIStatefulFrame.h"
 
 // Drag & Drop, Clipboard
 #include "nsWidgetsCID.h"
@@ -174,7 +176,9 @@ public:
   NS_IMETHOD GetFrameManager(nsIFrameManager** aFrameManager) const;
 
   NS_IMETHOD DoCopy();
- 
+  NS_IMETHOD GetHistoryState(nsILayoutHistoryState** aLayoutHistoryState);
+  NS_IMETHOD CaptureFrameState(nsIFrame* aFrame, nsILayoutHistoryState* aState);
+
   //nsIViewObserver interface
 
   NS_IMETHOD Paint(nsIView *aView,
@@ -1550,6 +1554,64 @@ PresShell::DoCopy()
   return NS_OK;
 }
 
+NS_IMETHODIMP
+PresShell::GetHistoryState(nsILayoutHistoryState** aState)
+{
+  nsresult rv = NS_OK;
+
+  NS_PRECONDITION(nsnull != aState, "null state pointer");
+
+  // Create the document state object
+  rv = NS_NewLayoutHistoryState(aState);
+  
+  if (NS_FAILED(rv)) { 
+    *aState = nsnull;
+    return rv;
+  }
+
+  // Capture frame state for the entire frame hierarchy
+  nsIFrame* rootFrame = nsnull;
+  rv = GetRootFrame(&rootFrame);
+  if (NS_FAILED(rv) || nsnull == rootFrame) return rv;
+
+  rv = CaptureFrameState(rootFrame, *aState);
+
+  return rv;
+}
+
+NS_IMETHODIMP
+PresShell::CaptureFrameState(nsIFrame* aFrame, nsILayoutHistoryState* aState)
+{
+  nsresult rv = NS_OK;
+  NS_PRECONDITION(nsnull != aFrame && nsnull != aState, "null parameters passed in");
+
+  // See if the frame is stateful.
+  nsCOMPtr<nsIStatefulFrame> statefulFrame = do_QueryInterface(aFrame);
+  if (nsnull != statefulFrame) {
+    // If so, ask the frame to save its state
+    rv = statefulFrame->SaveState(aState);    
+  }
+
+  // XXX We are only going through the principal child list right now.
+  // Need to talk to Troy to find out about other kinds of
+  // child lists and whether they will contain stateful frames.
+
+  // Capture frame state for the first child 
+  nsIFrame* child = nsnull;
+  rv = aFrame->FirstChild(nsnull, &child);
+  if (NS_SUCCEEDED(rv) && nsnull != child) {
+    rv = CaptureFrameState(child, aState);
+  }
+
+  // Capture frame state for the next sibling
+  nsIFrame* sibling = nsnull;
+  rv = aFrame->GetNextSibling(&sibling);
+  if (NS_SUCCEEDED(rv) && nsnull != sibling) {
+    rv = CaptureFrameState(sibling, aState);    
+  }
+
+  return rv;
+}
 
 NS_IMETHODIMP
 PresShell::ContentChanged(nsIDocument *aDocument,

layout/base/public/MANIFEST

@@ -43,3 +43,5 @@ nsIStyleSheetLinkingElement.h
 nsITextContent.h
 nsTextFragment.h
 nsIAnonymousContent.h
+nsILayoutHistoryState.h
+nsIStatefulFrame.h

layout/base/public/Makefile.in

@@ -67,6 +67,8 @@ EXPORTS =				\
 	nsStyleCoord.h			\
 	nsStyleStruct.h			\
 	nsTextFragment.h		\
+	nsILayoutHistoryState.h \
+	nsIStatefulFrame.h \
 	$(NULL)
 
 EXPORTS := $(addprefix $(srcdir)/, $(EXPORTS))

layout/base/public/makefile.win

@@ -60,6 +60,8 @@ EXPORTS =				\
 	nsStyleCoord.h			\
 	nsStyleStruct.h			\
 	nsTextFragment.h		\
+	nsILayoutHistoryState.h \
+	nsIStatefulFrame.h \
 	$(NULL)
 
 MODULE=raptor 

layout/base/public/nsILayoutHistoryState.h

@@ -0,0 +1,25 @@
+#ifndef _nsILayoutHistoryState_h
+#define _nsILayoutHistoryState_h
+
+#include "nsISupports.h"
+
+#define NS_ILAYOUTHISTORYSTATE_IID_STR "306c8ca0-5f0c-11d3-a9fb-000064657374"
+
+#define NS_ILAYOUTHISTORYSTATE_IID \
+{0x306c8ca0, 0x5f0c, 0x11d3, \
+{0xa9, 0xfb, 0x00, 0x00, 0x64, 0x65, 0x73, 0x74}}
+
+#define NS_HISTORY_STATE_TYPE_NONE -1
+
+class nsILayoutHistoryState : public nsISupports {
+ public: 
+  NS_DEFINE_STATIC_IID_ACCESSOR(NS_ILAYOUTHISTORYSTATE_IID)
+
+  NS_IMETHOD AddState(PRUint32 aContentID, nsISupports* aState, PRInt32 aStateType) = 0;
+  NS_IMETHOD GetState(PRUint32 aContentID, nsISupports** aState, PRInt32 aStateType) = 0;
+};
+
+nsresult
+NS_NewLayoutHistoryState(nsILayoutHistoryState** aState);
+
+#endif /* _nsILayoutHistoryState_h */

layout/base/public/nsIPresShell.h

@@ -40,6 +40,7 @@ class nsICaret;
 class nsIStyleContext;
 class nsIFrameSelection;
 class nsIFrameManager;
+class nsILayoutHistoryState;
 
 #define NS_IPRESSHELL_IID     \
 { 0x76e79c60, 0x944e, 0x11d1, \
@@ -336,6 +337,18 @@ public:
 
   // XXX events
   // XXX selection
+  
+  /**
+   * Get the history state for the current document 
+   */
+  NS_IMETHOD GetHistoryState(nsILayoutHistoryState** aLayoutHistoryState) = 0;
+
+  /**
+   * Capture frame state for the frame subtree rooted at aFrame.
+   * aState is the document state storage object onto which each frame 
+   * stores its state.
+   */
+  NS_IMETHOD CaptureFrameState(nsIFrame* aFrame, nsILayoutHistoryState* aState) = 0;
 
   /**
    * See if reflow verification is enabled. To enable reflow verification add
@@ -349,6 +362,7 @@ public:
    * Set the verify-reflow enable flag.
    */
   static NS_LAYOUT void SetVerifyReflowEnable(PRBool aEnabled);
+
 };
 
 /**

layout/base/public/nsIStatefulFrame.h

@@ -0,0 +1,20 @@
+#ifndef _nsIStatefulFrame_h
+#define _nsIStatefulFrame_h
+
+#include "nsISupports.h"
+
+#define NS_ISTATEFULFRAME_IID_STR "306c8ca0-5f0c-11d3-a9fb-000064657374"
+
+#define NS_ISTATEFULFRAME_IID \
+{0x306c8ca0, 0x5f0c, 0x11d3, \
+{0xa9, 0xfb, 0x00, 0x00, 0x64, 0x65, 0x73, 0x74}}
+
+class nsIStatefulFrame : public nsISupports {
+ public: 
+  NS_DEFINE_STATIC_IID_ACCESSOR(NS_ISTATEFULFRAME_IID)
+
+  NS_IMETHOD SaveState(nsILayoutHistoryState* aState);
+  NS_IMETHOD RestoreState(nsILayoutHistoryState* aState);
+};
+
+#endif /* _nsIStatefulFrame_h */

layout/base/src/Makefile.in

@@ -63,6 +63,7 @@ CPPSRCS =				\
 	nsTextFragment.cpp		\
 	nsTextNode.cpp			\
 	nsXIFConverter.cpp		\
+	nsLayoutHistoryState.cpp \
 	$(NULL)
 
 EXPORTS = \

layout/base/src/makefile.win

@@ -59,6 +59,7 @@ CPPSRCS =				\
 	nsCaret.cpp			\
 	nsRange.cpp			\
 	nsTextNode.cpp			\
+	nsLayoutHistoryState.cpp	\
 	$(NULL)
 
 MODULE=raptor 
@@ -101,6 +102,7 @@ CPP_OBJS=					\
 	.\$(OBJDIR)\nsCaret.obj			\
 	.\$(OBJDIR)\nsRange.obj			\
 	.\$(OBJDIR)\nsTextNode.obj		\
+	.\$(OBJDIR)\nsLayoutHistoryState.obj	\
 	$(NULL)
 
 LINCS=-I$(PUBLIC)\xpcom -I$(PUBLIC)\raptor \

layout/base/src/nsLayoutHistoryState.cpp

@@ -0,0 +1,87 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ *
+ * The contents of this file are subject to the Netscape Public License
+ * Version 1.0 (the "NPL"); you may not use this file except in
+ * compliance with the NPL.  You may obtain a copy of the NPL at
+ * http://www.mozilla.org/NPL/
+ *
+ * Software distributed under the NPL is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
+ * for the specific language governing rights and limitations under the
+ * NPL.
+ *
+ * The Initial Developer of this code under the NPL is Netscape
+ * Communications Corporation.  Portions created by Netscape are
+ * Copyright (C) 1998 Netscape Communications Corporation.  All Rights
+ * Reserved.
+ */
+
+#include "nsILayoutHistoryState.h"
+#include "nsHashtable.h"
+
+class nsLayoutHistoryState : public nsILayoutHistoryState
+{
+public:
+  nsLayoutHistoryState();
+  virtual ~nsLayoutHistoryState();
+
+  NS_DECL_ISUPPORTS
+
+  // nsILayoutHistoryState
+  NS_IMETHOD AddState(PRUint32 aContentID,
+    nsISupports* aState,
+    PRInt32 aStateType = NS_HISTORY_STATE_TYPE_NONE);
+  NS_IMETHOD GetState(PRUint32 aContentID,
+    nsISupports** aState,
+    PRInt32 aStateType = NS_HISTORY_STATE_TYPE_NONE);
+
+private:
+  nsSupportsHashtable mStates;
+};
+
+nsresult
+NS_NewLayoutHistoryState(nsILayoutHistoryState** aState)
+{
+    NS_PRECONDITION(aState != nsnull, "null ptr");
+    if (! aState)
+        return NS_ERROR_NULL_POINTER;
+
+    *aState = new nsLayoutHistoryState();
+    if (! *aState)
+        return NS_ERROR_OUT_OF_MEMORY;
+
+    NS_ADDREF(*aState);
+
+    return NS_OK;
+}
+
+nsLayoutHistoryState::nsLayoutHistoryState()
+{
+  NS_INIT_REFCNT();
+  
+
+}
+
+nsLayoutHistoryState::~nsLayoutHistoryState()
+{
+
+}
+
+NS_IMPL_ISUPPORTS(nsLayoutHistoryState, 
+                  nsILayoutHistoryState::GetIID());
+
+NS_IMETHODIMP
+nsLayoutHistoryState::AddState(PRUint32 aContentID,                                
+                               nsISupports* aState, 
+                               PRInt32 aStateType)
+{
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsLayoutHistoryState::GetState(PRUint32 aContentID,                                
+                               nsISupports** aState,
+                               PRInt32 aStateType)
+{
+  return NS_OK;
+}

layout/generic/nsIStatefulFrame.h

@@ -0,0 +1,20 @@
+#ifndef _nsIStatefulFrame_h
+#define _nsIStatefulFrame_h
+
+#include "nsISupports.h"
+
+#define NS_ISTATEFULFRAME_IID_STR "306c8ca0-5f0c-11d3-a9fb-000064657374"
+
+#define NS_ISTATEFULFRAME_IID \
+{0x306c8ca0, 0x5f0c, 0x11d3, \
+{0xa9, 0xfb, 0x00, 0x00, 0x64, 0x65, 0x73, 0x74}}
+
+class nsIStatefulFrame : public nsISupports {
+ public: 
+  NS_DEFINE_STATIC_IID_ACCESSOR(NS_ISTATEFULFRAME_IID)
+
+  NS_IMETHOD SaveState(nsILayoutHistoryState* aState);
+  NS_IMETHOD RestoreState(nsILayoutHistoryState* aState);
+};
+
+#endif /* _nsIStatefulFrame_h */

layout/html/base/src/nsPresShell.cpp

@@ -62,6 +62,8 @@
 #include "nsViewsCID.h"
 #include "nsIFrameManager.h"
 #include "nsISupportsPrimitives.h"
+#include "nsILayoutHistoryState.h"
+#include "nsIStatefulFrame.h"
 
 // Drag & Drop, Clipboard
 #include "nsWidgetsCID.h"
@@ -174,7 +176,9 @@ public:
   NS_IMETHOD GetFrameManager(nsIFrameManager** aFrameManager) const;
 
   NS_IMETHOD DoCopy();
- 
+  NS_IMETHOD GetHistoryState(nsILayoutHistoryState** aLayoutHistoryState);
+  NS_IMETHOD CaptureFrameState(nsIFrame* aFrame, nsILayoutHistoryState* aState);
+
   //nsIViewObserver interface
 
   NS_IMETHOD Paint(nsIView *aView,
@@ -1550,6 +1554,64 @@ PresShell::DoCopy()
   return NS_OK;
 }
 
+NS_IMETHODIMP
+PresShell::GetHistoryState(nsILayoutHistoryState** aState)
+{
+  nsresult rv = NS_OK;
+
+  NS_PRECONDITION(nsnull != aState, "null state pointer");
+
+  // Create the document state object
+  rv = NS_NewLayoutHistoryState(aState);
+  
+  if (NS_FAILED(rv)) { 
+    *aState = nsnull;
+    return rv;
+  }
+
+  // Capture frame state for the entire frame hierarchy
+  nsIFrame* rootFrame = nsnull;
+  rv = GetRootFrame(&rootFrame);
+  if (NS_FAILED(rv) || nsnull == rootFrame) return rv;
+
+  rv = CaptureFrameState(rootFrame, *aState);
+
+  return rv;
+}
+
+NS_IMETHODIMP
+PresShell::CaptureFrameState(nsIFrame* aFrame, nsILayoutHistoryState* aState)
+{
+  nsresult rv = NS_OK;
+  NS_PRECONDITION(nsnull != aFrame && nsnull != aState, "null parameters passed in");
+
+  // See if the frame is stateful.
+  nsCOMPtr<nsIStatefulFrame> statefulFrame = do_QueryInterface(aFrame);
+  if (nsnull != statefulFrame) {
+    // If so, ask the frame to save its state
+    rv = statefulFrame->SaveState(aState);    
+  }
+
+  // XXX We are only going through the principal child list right now.
+  // Need to talk to Troy to find out about other kinds of
+  // child lists and whether they will contain stateful frames.
+
+  // Capture frame state for the first child 
+  nsIFrame* child = nsnull;
+  rv = aFrame->FirstChild(nsnull, &child);
+  if (NS_SUCCEEDED(rv) && nsnull != child) {
+    rv = CaptureFrameState(child, aState);
+  }
+
+  // Capture frame state for the next sibling
+  nsIFrame* sibling = nsnull;
+  rv = aFrame->GetNextSibling(&sibling);
+  if (NS_SUCCEEDED(rv) && nsnull != sibling) {
+    rv = CaptureFrameState(sibling, aState);    
+  }
+
+  return rv;
+}
 
 NS_IMETHODIMP
 PresShell::ContentChanged(nsIDocument *aDocument,