[gtk+] quartz: fix crash in the recent clipboard "fix", and really fix it

[Michael Natterer <mitch src gnome org>]

commit 9d31a04d129d7bc10f5b5e1922ee919c0063212c
Author: Michael Natterer <mitch lanedo com>
Date:   Fri Dec 7 12:19:52 2012 +0100

    quartz: fix crash in the recent clipboard "fix", and really fix it
    
    We must not release the GtkClipboardOwner in pasteboardChangedOwner
    becaue we don't own a reference to ourselves (NSPasteboard does).
    Instead, release the owner right after setting it, transferring
    ownership to NSPasteboard
    
    Also, fix repeated setting of the same owner by keeping the
    owner around in GtkCLipboard, and re-use it if "user_data"
    doesn't change. To avoid clipboard_unset()ting our own contents
    in the process, add an ugly "setting_same_owner" boolean to
    GtkClipboardOwner, set it during re-setting the same owner,
    and avoid calling clipboard_unset() from pasteboardChangedOwner
    if it's TRUE.
    (cherry picked from commit 4a8df7a33c298d22bf78b947d0e861fc03ec70e1)

 gtk/gtkclipboard-quartz.c |   55 +++++++++++++++++++++++++++++---------------
 1 files changed, 36 insertions(+), 19 deletions(-)
---
diff --git a/gtk/gtkclipboard-quartz.c b/gtk/gtkclipboard-quartz.c
index 9a01b7c..046fe71 100644
--- a/gtk/gtkclipboard-quartz.c
+++ b/gtk/gtkclipboard-quartz.c
@@ -38,6 +38,13 @@ enum {
   LAST_SIGNAL
 };
 
+ interface GtkClipboardOwner : NSObject {
+  GtkClipboard *clipboard;
+  gboolean setting_same_owner;
+}
+
+ end
+
 typedef struct _GtkClipboardClass GtkClipboardClass;
 
 struct _GtkClipboard 
@@ -45,6 +52,7 @@ struct _GtkClipboard
   GObject parent_instance;
 
   NSPasteboard *pasteboard;
+  GtkClipboardOwner *owner;
   NSInteger change_count;
 
   GdkAtom selection;
@@ -87,12 +95,6 @@ static GtkClipboard *clipboard_peek       (GdkDisplay       *display,
 					   GdkAtom           selection,
 					   gboolean          only_if_exists);
 
- interface GtkClipboardOwner : NSObject {
-  GtkClipboard *clipboard;
-}
-
- end
-
 @implementation GtkClipboardOwner
 -(void)pasteboard:(NSPasteboard *)sender provideDataForType:(NSString *)type
 {
@@ -131,9 +133,8 @@ static GtkClipboard *clipboard_peek       (GdkDisplay       *display,
  */
 - (void)pasteboardChangedOwner:(NSPasteboard *)sender
 {
-  clipboard_unset (clipboard);
-
-  [self release];
+  if (! setting_same_owner)
+    clipboard_unset (clipboard);
 }
 
 - (id)initWithClipboard:(GtkClipboard *)aClipboard
@@ -143,6 +144,7 @@ static GtkClipboard *clipboard_peek       (GdkDisplay       *display,
   if (self) 
     {
       clipboard = aClipboard;
+      setting_same_owner = FALSE;
     }
 
   return self;
@@ -333,10 +335,6 @@ gtk_clipboard_set_contents (GtkClipboard         *clipboard,
   NSSet *types;
   NSAutoreleasePool *pool;
 
-  pool = [[NSAutoreleasePool alloc] init];
-
-  owner = [[GtkClipboardOwner alloc] initWithClipboard:clipboard];
-
   if (!(clipboard->have_owner && have_owner) ||
       clipboard->user_data != user_data)
     {
@@ -351,26 +349,44 @@ gtk_clipboard_set_contents (GtkClipboard         *clipboard,
               clipboard->user_data != user_data)
             {
               (*clear_func) (clipboard, user_data);
-              [pool release];
               return FALSE;
             }
           else
             {
-              [pool release];
               return TRUE;
             }
         }
     }
 
+  pool = [[NSAutoreleasePool alloc] init];
+
+  types = _gtk_quartz_target_entries_to_pasteboard_types (targets, n_targets);
+
   /*  call declareTypes before setting the clipboard members because
    *  declareTypes might clear the clipboard
    */
-  types = _gtk_quartz_target_entries_to_pasteboard_types (targets, n_targets);
-  clipboard->change_count = [clipboard->pasteboard declareTypes: [types allObjects]
-                                                          owner: owner];
+  if (user_data && user_data == clipboard->user_data)
+    {
+      owner = [clipboard->owner retain];
+
+      owner->setting_same_owner = TRUE;
+      clipboard->change_count = [clipboard->pasteboard declareTypes: [types allObjects]
+                                                              owner: owner];
+      owner->setting_same_owner = FALSE;
+    }
+  else
+    {
+      owner = [[GtkClipboardOwner alloc] initWithClipboard:clipboard];
+
+      clipboard->change_count = [clipboard->pasteboard declareTypes: [types allObjects]
+                                                              owner: owner];
+    }
+
+  [owner release];
   [types release];
   [pool release];
 
+  clipboard->owner = owner;
   clipboard->user_data = user_data;
   clipboard->have_owner = have_owner;
   if (have_owner)
@@ -459,7 +475,8 @@ clipboard_unset (GtkClipboard *clipboard)
   clipboard->n_storable_targets = -1;
   g_free (clipboard->storable_targets);
   clipboard->storable_targets = NULL;
-      
+
+  clipboard->owner = NULL;
   clipboard->get_func = NULL;
   clipboard->clear_func = NULL;
   clipboard->user_data = NULL;