[gimp] Move refing/unrefing the image to gimp_display_set_image()

[Michael Natterer <mitch src gnome org>]

commit dd0575edb47602021b7dd0e723b6a58a2f645205
Author: Michael Natterer <mitch gimp org>
Date:   Wed Oct 7 21:13:39 2009 +0200

    Move refing/unrefing the image to gimp_display_set_image()
    
    and don't do it in gimp_display_connect()/disconnect() because
    set_image() is the natural place to do it.

 app/display/gimpdisplay-handlers.c |   56 +++++++++++------------------------
 app/display/gimpdisplay-handlers.h |    3 +-
 app/display/gimpdisplay.c          |   28 ++++++++++++++++--
 3 files changed, 44 insertions(+), 43 deletions(-)
---
diff --git a/app/display/gimpdisplay-handlers.c b/app/display/gimpdisplay-handlers.c
index 738dcb0..4539f07 100644
--- a/app/display/gimpdisplay-handlers.c
+++ b/app/display/gimpdisplay-handlers.c
@@ -30,36 +30,30 @@
 
 /*  local function prototypes  */
 
-static void   gimp_display_update_handler    (GimpProjection *projection,
-                                              gboolean        now,
-                                              gint            x,
-                                              gint            y,
-                                              gint            w,
-                                              gint            h,
-                                              GimpDisplay    *display);
-static void   gimp_display_flush_handler     (GimpImage      *image,
-                                              gboolean        invalidate_preview,
-                                              GimpDisplay    *display);
+static void   gimp_display_update_handler (GimpProjection *projection,
+                                           gboolean        now,
+                                           gint            x,
+                                           gint            y,
+                                           gint            w,
+                                           gint            h,
+                                           GimpDisplay    *display);
+static void   gimp_display_flush_handler  (GimpImage      *image,
+                                           gboolean        invalidate_preview,
+                                           GimpDisplay    *display);
 
 
 /*  public functions  */
 
 void
-gimp_display_connect (GimpDisplay *display,
-                      GimpImage   *image)
+gimp_display_connect (GimpDisplay *display)
 {
-  g_return_if_fail (GIMP_IS_DISPLAY (display));
-  g_return_if_fail (GIMP_IS_IMAGE (image));
-  g_return_if_fail (display->image == NULL);
+  GimpImage *image;
 
-#if 0
-  g_print ("%s: image->ref_count before refing: %d\n",
-           G_STRFUNC, G_OBJECT (display->image)->ref_count);
-#endif
+  g_return_if_fail (GIMP_IS_DISPLAY (display));
 
-  display->image = g_object_ref (image);
+  image = gimp_display_get_image (display);
 
-  image->disp_count++;
+  g_return_if_fail (GIMP_IS_IMAGE (image));
 
   g_signal_connect (gimp_image_get_projection (image), "update",
                     G_CALLBACK (gimp_display_update_handler),
@@ -76,9 +70,10 @@ gimp_display_disconnect (GimpDisplay *display)
   GimpImage *image;
 
   g_return_if_fail (GIMP_IS_DISPLAY (display));
-  g_return_if_fail (GIMP_IS_IMAGE (display->image));
 
-  image = display->image;
+  image = gimp_display_get_image (display);
+
+  g_return_if_fail (GIMP_IS_IMAGE (image));
 
   g_signal_handlers_disconnect_by_func (image,
                                         gimp_display_flush_handler,
@@ -87,21 +82,6 @@ gimp_display_disconnect (GimpDisplay *display)
   g_signal_handlers_disconnect_by_func (gimp_image_get_projection (image),
                                         gimp_display_update_handler,
                                         display);
-
-  image->disp_count--;
-
-#if 0
-  g_print ("%s: image->ref_count before unrefing: %d\n",
-           G_STRFUNC, G_OBJECT (display->image)->ref_count);
-#endif
-
-  /*  set display->image to NULL before unrefing because there may be code
-   *  that listens for image removals and then iterates the display list
-   *  to find a valid display.
-   */
-  display->image = NULL;
-
-  g_object_unref (image);
 }
 
 
diff --git a/app/display/gimpdisplay-handlers.h b/app/display/gimpdisplay-handlers.h
index 5ed3b3d..9b03c34 100644
--- a/app/display/gimpdisplay-handlers.h
+++ b/app/display/gimpdisplay-handlers.h
@@ -19,8 +19,7 @@
 #define __GIMP_DISPLAY_HANDLERS_H__
 
 
-void   gimp_display_connect    (GimpDisplay *display,
-                                GimpImage   *image);
+void   gimp_display_connect    (GimpDisplay *display);
 void   gimp_display_disconnect (GimpDisplay *display);
 
 
diff --git a/app/display/gimpdisplay.c b/app/display/gimpdisplay.c
index c46fdfc..e1be801 100644
--- a/app/display/gimpdisplay.c
+++ b/app/display/gimpdisplay.c
@@ -627,16 +627,38 @@ gimp_display_set_image (GimpDisplay *display,
 
       gimp_display_shell_disconnect (shell);
 
-      old_image = g_object_ref (display->image);
-
       gimp_display_disconnect (display);
+
+      display->image->disp_count--;
+
+      /*  set display->image before unrefing because there may be code
+       *  that listens for image removals and then iterates the
+       *  display list to find a valid display.
+       */
+      old_image = display->image;
+
+#if 0
+      g_print ("%s: image->ref_count before unrefing: %d\n",
+               G_STRFUNC, G_OBJECT (old_image)->ref_count);
+#endif
     }
 
+  display->image = image;
+
   if (image)
     {
+#if 0
+      g_print ("%s: image->ref_count before refing: %d\n",
+               G_STRFUNC, G_OBJECT (image)->ref_count);
+#endif
+
+      g_object_ref (image);
+
       private->instance = image->instance_count++;
 
-      gimp_display_connect (display, image);
+      image->disp_count++;
+
+      gimp_display_connect (display);
 
       if (shell)
         gimp_display_shell_connect (shell);