Merge eog-menu-api branch

2003-01-20  Marco Pesenti Gritti  <marco@it.gnome.org>

	* Merge eog-menu-api branch

1 files changed, 1316 insertions, 0 deletions

diff --git a/lib/egg/egg-menu-merge.c b/lib/egg/egg-menu-merge.c
new file mode 100644
index 000000000..17895ca99
--- /dev/null
+++ b/lib/egg/egg-menu-merge.c
@@ -0,0 +1,1316 @@
+#include <string.h>
+#include "egg-menu-merge.h"
+#include "eggtoolbar.h"
+#include "eggseparatortoolitem.h"
+
+#ifndef _
+#  define _(string) (string)
+#endif
+
+#define NODE_INFO(node) ((EggMenuMergeNode *)node->data)
+
+typedef struct {
+  guint merge_id;
+  GQuark action_quark;
+} NodeUIReference;
+
+static void   egg_menu_merge_class_init    (EggMenuMergeClass *class);
+static void   egg_menu_merge_init          (EggMenuMerge *merge);
+
+static void   egg_menu_merge_queue_update  (EggMenuMerge *self);
+static void   egg_menu_merge_dirty_all     (EggMenuMerge *self);
+
+static GNode *get_child_node               (EggMenuMerge *self, GNode *parent,
+					    const gchar *childname,
+					    gint childname_length,
+					    EggMenuMergeNodeType node_type,
+					    gboolean create, gboolean top);
+static GNode *egg_menu_merge_get_node      (EggMenuMerge *self,
+					    const gchar *path,
+					    EggMenuMergeNodeType node_type,
+					    gboolean create);
+static guint egg_menu_merge_next_merge_id  (EggMenuMerge *self);
+
+static void  egg_menu_merge_node_prepend_ui_reference (EggMenuMergeNode *node,
+						       guint merge_id,
+						       GQuark action_quark);
+static void  egg_menu_merge_node_remove_ui_reference  (EggMenuMergeNode *node,
+						       guint merge_id);
+
+enum {
+  ADD_WIDGET,
+  REMOVE_WIDGET,
+  LAST_SIGNAL
+};
+
+static guint merge_signals[LAST_SIGNAL] = { 0 };
+
+static GMemChunk *merge_node_chunk = NULL;
+
+GType
+egg_menu_merge_get_type (void)
+{
+  static GtkType type = 0;
+
+  if (!type)
+    {
+      static const GTypeInfo type_info =
+      {
+        sizeof (EggMenuMergeClass),
+        (GBaseInitFunc) NULL,
+        (GBaseFinalizeFunc) NULL,
+        (GClassInitFunc) egg_menu_merge_class_init,
+        (GClassFinalizeFunc) NULL,
+        NULL,
+        
+        sizeof (EggMenuMerge),
+        0, /* n_preallocs */
+        (GInstanceInitFunc) egg_menu_merge_init,
+      };
+
+      type = g_type_register_static (G_TYPE_OBJECT,
+				     "EggMenuMerge",
+				     &type_info, 0);
+    }
+  return type;
+}
+
+static void
+egg_menu_merge_class_init (EggMenuMergeClass *class)
+{
+  if (!merge_node_chunk)
+    merge_node_chunk = g_mem_chunk_create(EggMenuMergeNode, 64,
+					  G_ALLOC_AND_FREE);
+
+  merge_signals[ADD_WIDGET] =
+    g_signal_new ("add_widget",
+		  G_OBJECT_CLASS_TYPE (class),
+		  G_SIGNAL_RUN_FIRST | G_SIGNAL_NO_RECURSE,
+		  G_STRUCT_OFFSET (EggMenuMergeClass, add_widget), NULL, NULL,
+		  g_cclosure_marshal_VOID__OBJECT,
+		  G_TYPE_NONE, 1,
+		  GTK_TYPE_WIDGET);
+  merge_signals[REMOVE_WIDGET] =
+    g_signal_new ("remove_widget",
+		  G_OBJECT_CLASS_TYPE (class),
+		  G_SIGNAL_RUN_FIRST | G_SIGNAL_NO_RECURSE,
+		  G_STRUCT_OFFSET (EggMenuMergeClass, remove_widget), NULL, NULL,
+		  g_cclosure_marshal_VOID__OBJECT,
+		  G_TYPE_NONE, 1,
+		  GTK_TYPE_WIDGET);  
+  
+}
+
+
+static void
+egg_menu_merge_init (EggMenuMerge *self)
+{
+  guint merge_id;
+  GNode *node;
+
+  self->accel_group = gtk_accel_group_new();
+
+  self->root_node = NULL;
+  self->action_groups = NULL;
+
+  self->last_merge_id = 0;
+
+
+  merge_id = egg_menu_merge_next_merge_id(self);
+  node = get_child_node(self, NULL, "Root", 4,
+			EGG_MENU_MERGE_ROOT, TRUE, FALSE);
+  egg_menu_merge_node_prepend_ui_reference(NODE_INFO(node), merge_id, 0);
+  node = get_child_node(self, self->root_node, "popups", 6,
+			EGG_MENU_MERGE_POPUPS, TRUE, FALSE);
+  egg_menu_merge_node_prepend_ui_reference(NODE_INFO(node), merge_id, 0);
+}
+
+EggMenuMerge *
+egg_menu_merge_new (void)
+{
+  return g_object_new(EGG_TYPE_MENU_MERGE, NULL);
+}
+
+void
+egg_menu_merge_insert_action_group (EggMenuMerge *self,
+				 EggActionGroup *action_group, gint pos)
+{
+  g_return_if_fail (EGG_IS_MENU_MERGE(self));
+  g_return_if_fail (EGG_IS_ACTION_GROUP(action_group));
+  g_return_if_fail (g_list_find(self->action_groups, action_group) == NULL);
+
+  g_object_ref(action_group);
+  self->action_groups = g_list_insert(self->action_groups, action_group, pos);
+
+  /* dirty all nodes, as action bindings may change */
+  egg_menu_merge_dirty_all(self);
+}
+
+void
+egg_menu_merge_remove_action_group (EggMenuMerge *self,
+				    EggActionGroup *action_group)
+{
+  g_return_if_fail (EGG_IS_MENU_MERGE(self));
+  g_return_if_fail (EGG_IS_ACTION_GROUP(action_group));
+  g_return_if_fail (g_list_find(self->action_groups, action_group) != NULL);
+
+  self->action_groups = g_list_remove(self->action_groups, action_group);
+  g_object_unref(action_group);
+
+  /* dirty all nodes, as action bindings may change */
+  egg_menu_merge_dirty_all(self);
+}
+
+GtkWidget *
+egg_menu_merge_get_widget (EggMenuMerge *self, const gchar *path)
+{
+  GNode *node;
+
+  /* ensure that there are no pending updates before we get the
+   * widget */
+  egg_menu_merge_ensure_update(self);
+
+  node = egg_menu_merge_get_node(self, path, EGG_MENU_MERGE_UNDECIDED, FALSE);
+  return NODE_INFO(node)->proxy;
+}
+
+static GNode *
+get_child_node(EggMenuMerge *self, GNode *parent,
+	       const gchar *childname, gint childname_length,
+	       EggMenuMergeNodeType node_type,
+	       gboolean create, gboolean top)
+{
+  GNode *child = NULL;
+
+  g_return_val_if_fail(parent == NULL ||
+	       (NODE_INFO(parent)->type != EGG_MENU_MERGE_MENUITEM &&
+		NODE_INFO(parent)->type != EGG_MENU_MERGE_TOOLITEM), NULL);
+
+  if (parent)
+    {
+      if (childname)
+	{
+	  for (child = parent->children; child != NULL; child = child->next)
+	    {
+	      if (strlen(NODE_INFO(child)->name) == childname_length &&
+		  !strncmp(NODE_INFO(child)->name, childname, childname_length))
+		{
+		  /* if undecided about node type, set it */
+		  if (NODE_INFO(child)->type == EGG_MENU_MERGE_UNDECIDED)
+		    NODE_INFO(child)->type = node_type;
+		  
+		  /* warn about type mismatch */
+		  if (NODE_INFO(child)->type != EGG_MENU_MERGE_UNDECIDED &&
+		      NODE_INFO(child)->type != node_type)
+		    g_warning("node type doesn't match %d (%s is type %d)",
+			      node_type, NODE_INFO(child)->name,
+			      NODE_INFO(child)->type);
+		  
+		  return child;
+		}
+	    }
+	}
+      if (!child && create)
+	{
+	  EggMenuMergeNode *mnode;
+
+	  mnode = g_chunk_new0(EggMenuMergeNode, merge_node_chunk);
+	  mnode->type = node_type;
+	  mnode->name = g_strndup(childname, childname_length);
+	  mnode->dirty = TRUE;
+
+	  if (top)
+	    child = g_node_prepend_data(parent, mnode);
+	  else
+	    child = g_node_append_data(parent, mnode);
+	}
+    }
+  else
+    {
+      /* handle root node */
+      if (self->root_node)
+	{
+	  child = self->root_node;
+	  if (strncmp(NODE_INFO(child)->name, childname, childname_length) !=0)
+	    g_warning("root node name '%s' doesn't match '%s'",
+		      childname, NODE_INFO(child)->name);
+	  if (NODE_INFO(child)->type != EGG_MENU_MERGE_ROOT)
+	    g_warning("base element must be of type ROOT");
+	}
+      else if (create)
+	{
+	  EggMenuMergeNode *mnode;
+
+	  mnode = g_chunk_new0(EggMenuMergeNode, merge_node_chunk);
+	  mnode->type = node_type;
+	  mnode->name = g_strndup(childname, childname_length);
+	  mnode->dirty = TRUE;
+	  
+	  child = self->root_node = g_node_new(mnode);
+	}
+    }
+
+  return child;
+}
+
+static GNode *
+egg_menu_merge_get_node(EggMenuMerge *self, const gchar *path,
+			EggMenuMergeNodeType node_type, gboolean create)
+{
+  const gchar *pos, *end;
+  GNode *parent, *node;
+
+  end = path + strlen(path);
+  pos = path;
+  parent = node = NULL;
+  while (pos < end)
+    {
+      const gchar *slash;
+      gsize length;
+
+      slash = strchr(pos, '/');
+      if (slash)
+	length = slash - pos;
+      else
+	length = strlen(pos);
+
+      node = get_child_node(self, parent, pos, length, EGG_MENU_MERGE_UNDECIDED,
+			    create, FALSE);
+      if (!node)
+	return NULL;
+
+      pos += length + 1; /* move past the node name and the slash too */
+      parent = node;
+    }
+
+  if (NODE_INFO(node)->type == EGG_MENU_MERGE_UNDECIDED)
+    NODE_INFO(node)->type = node_type;
+  return node;
+}
+
+static guint
+egg_menu_merge_next_merge_id (EggMenuMerge *self)
+{
+  self->last_merge_id++;
+
+  return self->last_merge_id;
+}
+
+static void
+egg_menu_merge_node_prepend_ui_reference (EggMenuMergeNode *node,
+					  guint merge_id, GQuark action_quark)
+{
+  NodeUIReference *reference;
+
+  reference = g_new (NodeUIReference, 1);
+  reference->action_quark = action_quark;
+  reference->merge_id = merge_id;
+
+  /* Prepend the reference */
+  node->uifiles = g_list_prepend (node->uifiles, reference);
+
+  node->dirty = TRUE;
+}
+
+static void
+egg_menu_merge_node_remove_ui_reference (EggMenuMergeNode *node,
+					 guint merge_id)
+{
+  GList *p;
+
+  for (p = node->uifiles; p != NULL; p = p->next)
+    {
+      NodeUIReference *reference = p->data;
+      
+      if (reference->merge_id == merge_id)
+	{
+	  node->uifiles = g_list_remove_link (node->uifiles, p);
+	  node->dirty = TRUE;
+	  g_free (reference);
+
+	  break;
+	}
+    }
+}
+
+/* -------------------- The UI file parser -------------------- */
+
+typedef enum {
+  STATE_START,
+  STATE_ROOT,
+  STATE_MENU,
+  STATE_TOOLBAR,
+  STATE_POPUPS,
+  STATE_MENUITEM,
+  STATE_TOOLITEM,
+  STATE_END
+} ParseState;
+
+typedef struct _ParseContext ParseContext;
+struct _ParseContext
+{
+  ParseState state;
+  ParseState prev_state;
+
+  EggMenuMerge *self;
+
+  GNode *current;
+
+  guint merge_id;
+};
+
+static void
+start_element_handler (GMarkupParseContext *context,
+		       const gchar *element_name,
+		       const gchar **attribute_names,
+		       const gchar **attribute_values,
+		       gpointer user_data,
+		       GError **error)
+{
+  ParseContext *ctx = user_data;
+  EggMenuMerge *self = ctx->self;
+
+  gint i;
+  const gchar *node_name;
+  GQuark verb_quark;
+  gboolean top;
+
+  gboolean raise_error = TRUE;
+  gchar *error_attr = NULL;
+
+  //g_message("starting element %s", element_name);
+
+  /* work out a name for this node.  Either the name attribute, or
+   * element name */
+  node_name = element_name;
+  verb_quark = 0;
+  top = FALSE;
+  for (i = 0; attribute_names[i] != NULL; i++)
+    {
+      if (!strcmp(attribute_names[i], "name"))
+	{
+	  node_name = attribute_values[i];
+	}
+      else if (!strcmp(attribute_names[i], "verb"))
+	{
+	  verb_quark = g_quark_from_string(attribute_values[i]);
+	}
+      else if (!strcmp(attribute_names[i], "pos"))
+	{
+	  top = !strcmp(attribute_values[i], "top");
+	}
+    }
+  /* if no verb, then set it to the node's name */
+  if (verb_quark == 0)
+    verb_quark = g_quark_from_string(node_name);
+
+  switch (element_name[0])
+    {
+    case 'R':
+      if (ctx->state == STATE_START && !strcmp(element_name, "Root"))
+	{
+	  ctx->state = STATE_ROOT;
+	  ctx->current = self->root_node;
+	  raise_error = FALSE;
+
+	  egg_menu_merge_node_prepend_ui_reference (NODE_INFO (ctx->current),
+						    ctx->merge_id, verb_quark);
+	}
+      break;
+    case 'm':
+      if (ctx->state == STATE_ROOT && !strcmp(element_name, "menu"))
+	{
+	  ctx->state = STATE_MENU;
+	  ctx->current = get_child_node(self, ctx->current,
+					node_name, strlen(node_name),
+					EGG_MENU_MERGE_MENUBAR,
+					TRUE, FALSE);
+	  if (NODE_INFO(ctx->current)->action_name == 0)
+	    NODE_INFO(ctx->current)->action_name = verb_quark;
+
+	  egg_menu_merge_node_prepend_ui_reference (NODE_INFO (ctx->current),
+						    ctx->merge_id, verb_quark);
+	  NODE_INFO(ctx->current)->dirty = TRUE;
+
+	  raise_error = FALSE;
+	}
+      else if (ctx->state == STATE_MENU && !strcmp(element_name, "menuitem"))
+	{
+	  GNode *node;
+
+	  ctx->state = STATE_MENUITEM;
+	  node = get_child_node(self, ctx->current,
+				node_name, strlen(node_name),
+				EGG_MENU_MERGE_MENUITEM,
+				TRUE, top);
+	  if (NODE_INFO(node)->action_name == 0)
+	    NODE_INFO(node)->action_name = verb_quark;
+
+	  egg_menu_merge_node_prepend_ui_reference (NODE_INFO (node),
+						    ctx->merge_id, verb_quark);
+	  NODE_INFO(node)->dirty = TRUE;
+
+	  raise_error = FALSE;
+	}
+      break;
+    case 'd':
+      if (ctx->state == STATE_ROOT && !strcmp(element_name, "dockitem"))
+	{
+	  ctx->state = STATE_TOOLBAR;
+	  ctx->current = get_child_node(self, ctx->current,
+					node_name, strlen(node_name),
+					EGG_MENU_MERGE_TOOLBAR,
+					TRUE, FALSE);
+	  if (NODE_INFO(ctx->current)->action_name == 0)
+	    NODE_INFO(ctx->current)->action_name = verb_quark;
+
+	  egg_menu_merge_node_prepend_ui_reference (NODE_INFO (ctx->current),
+						    ctx->merge_id, verb_quark);
+	  NODE_INFO(ctx->current)->dirty = TRUE;
+
+	  raise_error = FALSE;
+	}
+      break;
+    case 'p':
+      if (ctx->state == STATE_ROOT && !strcmp(element_name, "popups"))
+	{
+	  ctx->state = STATE_POPUPS;
+	  ctx->current = get_child_node(self, ctx->current,
+					node_name, strlen(node_name),
+					EGG_MENU_MERGE_POPUPS,
+					TRUE, FALSE);
+
+	  egg_menu_merge_node_prepend_ui_reference (NODE_INFO (ctx->current),
+						    ctx->merge_id, verb_quark);
+	  NODE_INFO(ctx->current)->dirty = TRUE;
+
+	  raise_error = FALSE;
+	}
+      else if (ctx->state == STATE_POPUPS && !strcmp(element_name, "popup"))
+	{
+	  ctx->state = STATE_MENU;
+	  ctx->current = get_child_node(self, ctx->current,
+					node_name, strlen(node_name),
+					EGG_MENU_MERGE_MENU,
+					TRUE, FALSE);
+	  if (NODE_INFO(ctx->current)->action_name == 0)
+	    NODE_INFO(ctx->current)->action_name = verb_quark;
+
+	  egg_menu_merge_node_prepend_ui_reference (NODE_INFO (ctx->current),
+						    ctx->merge_id, verb_quark);
+	  NODE_INFO(ctx->current)->dirty = TRUE;
+
+	  raise_error = FALSE;
+	}
+      else if ((ctx->state == STATE_MENU || ctx->state == STATE_TOOLBAR) &&
+	       !strcmp(element_name, "placeholder"))
+	{
+	  if (ctx->state == STATE_MENU)
+	    ctx->current = get_child_node(self, ctx->current,
+					  node_name, strlen(node_name),
+					  EGG_MENU_MERGE_MENU_PLACEHOLDER,
+					  TRUE, top);
+	  else
+	    ctx->current = get_child_node(self, ctx->current,
+					  node_name, strlen(node_name),
+					  EGG_MENU_MERGE_TOOLBAR_PLACEHOLDER,
+					  TRUE, top);
+
+	  egg_menu_merge_node_prepend_ui_reference (NODE_INFO (ctx->current),
+						    ctx->merge_id, verb_quark);
+	  NODE_INFO(ctx->current)->dirty = TRUE;
+
+	  raise_error = FALSE;
+	}
+      break;
+    case 's':
+      if (ctx->state == STATE_MENU && !strcmp(element_name, "submenu"))
+	{
+	  ctx->state = STATE_MENU;
+	  ctx->current = get_child_node(self, ctx->current,
+					node_name, strlen(node_name),
+					EGG_MENU_MERGE_MENU,
+					TRUE, top);
+	  if (NODE_INFO(ctx->current)->action_name == 0)
+	    NODE_INFO(ctx->current)->action_name = verb_quark;
+
+	  egg_menu_merge_node_prepend_ui_reference (NODE_INFO (ctx->current),
+						    ctx->merge_id, verb_quark);
+	  NODE_INFO(ctx->current)->dirty = TRUE;
+
+	  raise_error = FALSE;
+	}
+      else if ((ctx->state == STATE_MENU || ctx->state == STATE_TOOLBAR) &&
+	       !strcmp(element_name, "separator"))
+	{
+	  GNode *node;
+
+	  if (ctx->state == STATE_MENU)
+	    ctx->state = STATE_MENUITEM;
+	  else
+	    ctx->state = STATE_TOOLITEM;
+	  node = get_child_node(self, ctx->current,
+				node_name, strlen(node_name),
+				EGG_MENU_MERGE_SEPARATOR,
+				TRUE, top);
+	  if (NODE_INFO(node)->action_name == 0)
+	    NODE_INFO(node)->action_name = verb_quark;
+
+	  egg_menu_merge_node_prepend_ui_reference (NODE_INFO (node),
+						    ctx->merge_id, verb_quark);
+	  NODE_INFO(node)->dirty = TRUE;
+
+	  raise_error = FALSE;
+	}
+      break;
+    case 't':
+      if (ctx->state == STATE_TOOLBAR && !strcmp(element_name, "toolitem"))
+	{
+	  GNode *node;
+
+	  ctx->state = STATE_TOOLITEM;
+	  node = get_child_node(self, ctx->current,
+				node_name, strlen(node_name),
+				EGG_MENU_MERGE_TOOLITEM,
+				TRUE, top);
+	  if (NODE_INFO(node)->action_name == 0)
+	    NODE_INFO(node)->action_name = verb_quark;
+
+	  egg_menu_merge_node_prepend_ui_reference (NODE_INFO (node),
+						    ctx->merge_id, verb_quark);
+	  NODE_INFO(node)->dirty = TRUE;
+
+	  raise_error = FALSE;
+	}
+      break;
+    default:
+      break;
+    }
+  if (raise_error)
+    {
+      gint line_number, char_number;
+ 
+      g_markup_parse_context_get_position (context,
+					   &line_number, &char_number);
+      if (error_attr)
+	g_set_error (error,
+		     G_MARKUP_ERROR,
+		     G_MARKUP_ERROR_UNKNOWN_ATTRIBUTE,
+		     _("Unknown attribute '%s' on line %d char %d"),
+		     error_attr,
+		     line_number, char_number);
+      else
+	g_set_error (error,
+		     G_MARKUP_ERROR,
+		     G_MARKUP_ERROR_UNKNOWN_ELEMENT,
+		     _("Unknown tag '%s' on line %d char %d"),
+		     element_name,
+		     line_number, char_number);
+    }
+}
+
+static void
+end_element_handler (GMarkupParseContext *context,
+		     const gchar *element_name,
+		     gpointer user_data,
+		     GError **error)
+{
+  ParseContext *ctx = user_data;
+  EggMenuMerge *self = ctx->self;
+
+  //g_message("ending element %s (state=%d)", element_name, ctx->state);
+
+  switch (ctx->state)
+    {
+    case STATE_START:
+      g_warning("shouldn't get any end tags in start state");
+      /* should we GError here? */
+      break;
+    case STATE_ROOT:
+      if (ctx->current != self->root_node)
+	g_warning("we are in STATE_ROOT, but the current node isn't the root");
+      ctx->current = NULL;
+      ctx->state = STATE_END;
+      break;
+    case STATE_MENU:
+      ctx->current = ctx->current->parent;
+      if (NODE_INFO(ctx->current)->type == EGG_MENU_MERGE_ROOT) /* menubar */
+	ctx->state = STATE_ROOT;
+      else if (NODE_INFO(ctx->current)->type == EGG_MENU_MERGE_POPUPS) /* popup */
+	ctx->state = STATE_POPUPS;
+      /* else, stay in STATE_MENU state */
+      break;
+    case STATE_TOOLBAR:
+      ctx->current = ctx->current->parent;
+      /* we conditionalise this test, in case we are closing off a
+       * placeholder */
+      if (NODE_INFO(ctx->current)->type == EGG_MENU_MERGE_ROOT)
+	ctx->state = STATE_ROOT;
+      /* else, stay in STATE_TOOLBAR state */
+      break;
+    case STATE_POPUPS:
+      ctx->current = ctx->current->parent;
+      ctx->state = STATE_ROOT;
+      break;
+    case STATE_MENUITEM:
+      ctx->state = STATE_MENU;
+      break;
+    case STATE_TOOLITEM:
+      ctx->state = STATE_TOOLBAR;
+      break;
+    case STATE_END:
+      g_warning("shouldn't get any end tags at this point");
+      /* should do an error here */
+      break;
+    }
+}
+
+static void
+cleanup (GMarkupParseContext *context,
+	 GError *error,
+	 gpointer user_data)
+{
+  ParseContext *ctx = user_data;
+  EggMenuMerge *self = ctx->self;
+
+  ctx->current = NULL;
+  /* should also walk through the tree and get rid of nodes related to
+   * this UI file's tag */
+
+  egg_menu_merge_remove_ui (self, ctx->merge_id);
+}
+
+static GMarkupParser ui_parser = {
+  start_element_handler,
+  end_element_handler,
+  NULL,
+  NULL,
+  cleanup
+};
+
+guint
+egg_menu_merge_add_ui_from_string (EggMenuMerge *self,
+				   const gchar *buffer, guint length,
+				   GError **error)
+{
+  ParseContext ctx = { 0 };
+  GMarkupParseContext *context;
+  gboolean res = TRUE;
+
+  g_return_val_if_fail(EGG_IS_MENU_MERGE(self), FALSE);
+  g_return_val_if_fail(buffer != NULL, FALSE);
+
+  ctx.state = STATE_START;
+  ctx.self = self;
+  ctx.current = NULL;
+  ctx.merge_id = egg_menu_merge_next_merge_id (self);
+
+  context = g_markup_parse_context_new(&ui_parser, 0, &ctx, NULL);
+  if (length < 0)
+    length = strlen(buffer);
+
+  if (g_markup_parse_context_parse(context, buffer, length, error))
+    {
+      if (!g_markup_parse_context_end_parse(context, error))
+	res = FALSE;
+    }
+  else
+    res = FALSE;
+
+  g_markup_parse_context_free (context);
+
+  egg_menu_merge_queue_update(self);
+
+  if (res)
+    return ctx.merge_id;
+  return 0;
+}
+
+guint
+egg_menu_merge_add_ui_from_file (EggMenuMerge *self,
+				 const gchar *filename,
+				 GError **error)
+{
+  gchar *buffer;
+  gint length;
+  guint res;
+
+  if (!g_file_get_contents (filename, &buffer, &length, error))
+    return 0;
+
+  res = egg_menu_merge_add_ui_from_string(self, buffer, length, error);
+  g_free(buffer);
+
+  return res;
+}
+
+static gboolean
+remove_ui (GNode *node, gpointer user_data)
+{
+  guint merge_id = GPOINTER_TO_UINT (user_data);
+
+  egg_menu_merge_node_remove_ui_reference (NODE_INFO (node), merge_id);
+
+  return FALSE; /* continue */
+}
+
+void
+egg_menu_merge_remove_ui (EggMenuMerge *self, guint merge_id)
+{
+  g_node_traverse(self->root_node, G_POST_ORDER, G_TRAVERSE_ALL, -1,
+		  remove_ui, GUINT_TO_POINTER (merge_id));
+
+  egg_menu_merge_queue_update(self);
+}
+
+/* -------------------- Updates -------------------- */
+
+
+static EggAction *
+get_action_by_name (EggMenuMerge *merge, const char *action_name)
+{
+  GList *tmp;
+
+  if (!action_name)
+    return NULL;
+  
+  /* lookup name */
+  for (tmp = merge->action_groups; tmp != NULL; tmp = tmp->next)
+    {
+      EggActionGroup *action_group = tmp->data;
+      EggAction *action;
+      
+      action = egg_action_group_get_action (action_group, action_name);
+
+      if (action)
+	return action;
+    }
+
+  return NULL;
+}
+
+static gboolean
+find_menu_position (GNode *node, GtkWidget **menushell_p, gint *pos_p)
+{
+  GtkWidget *menushell;
+  gint pos;
+
+  g_return_val_if_fail(node != NULL, FALSE);
+  g_return_val_if_fail(NODE_INFO(node)->type == EGG_MENU_MERGE_MENU ||
+		       NODE_INFO(node)->type == EGG_MENU_MERGE_MENU_PLACEHOLDER ||
+		       NODE_INFO(node)->type == EGG_MENU_MERGE_MENUITEM ||
+		       NODE_INFO(node)->type == EGG_MENU_MERGE_SEPARATOR,
+		       FALSE);
+
+  /* first sibling -- look at parent */
+  if (node->prev == NULL)
+    {
+      GNode *parent;
+
+      parent = node->parent;
+      switch (NODE_INFO(parent)->type)
+	{
+	case EGG_MENU_MERGE_MENUBAR:
+	  menushell = NODE_INFO(parent)->proxy;
+	  pos = 0;
+	  break;
+	case EGG_MENU_MERGE_MENU:
+	  menushell = NODE_INFO(parent)->proxy;
+	  if (GTK_IS_MENU_ITEM(menushell))
+	    menushell = gtk_menu_item_get_submenu(GTK_MENU_ITEM(menushell));
+	  pos = 0;
+	  break;
+	case EGG_MENU_MERGE_MENU_PLACEHOLDER:
+	  menushell = gtk_widget_get_parent(NODE_INFO(parent)->proxy);
+	  g_return_val_if_fail(GTK_IS_MENU_SHELL(menushell), FALSE);
+	  pos = g_list_index(GTK_MENU_SHELL(menushell)->children,
+			     NODE_INFO(parent)->proxy) + 1;
+	  break;
+	default:
+	  g_warning("%s: bad parent node type %d", G_STRLOC,
+		    NODE_INFO(parent)->type);
+	  return FALSE;
+	}
+    }
+  else
+    {
+      GtkWidget *prev_child;
+      GNode *sibling;
+
+      sibling = node->prev;
+      if (NODE_INFO(sibling)->type == EGG_MENU_MERGE_MENU_PLACEHOLDER)
+	prev_child = NODE_INFO(sibling)->extra; /* second Separator */
+      else
+	prev_child = NODE_INFO(sibling)->proxy;
+
+      g_return_val_if_fail(GTK_IS_WIDGET(prev_child), FALSE);
+      menushell = gtk_widget_get_parent(prev_child);
+      g_return_val_if_fail(GTK_IS_MENU_SHELL(menushell), FALSE);
+
+      pos = g_list_index(GTK_MENU_SHELL(menushell)->children, prev_child) + 1;
+    }
+
+  if (menushell_p)
+    *menushell_p = menushell;
+  if (pos_p)
+    *pos_p = pos;
+
+  return TRUE;
+}
+
+static gboolean
+find_toolbar_position (GNode *node, GtkWidget **toolbar_p, gint *pos_p)
+{
+  GtkWidget *toolbar;
+  gint pos;
+
+  g_return_val_if_fail(node != NULL, FALSE);
+  g_return_val_if_fail(NODE_INFO(node)->type == EGG_MENU_MERGE_TOOLBAR ||
+		       NODE_INFO(node)->type == EGG_MENU_MERGE_TOOLBAR_PLACEHOLDER ||
+		       NODE_INFO(node)->type == EGG_MENU_MERGE_TOOLITEM ||
+		       NODE_INFO(node)->type == EGG_MENU_MERGE_SEPARATOR,
+		       FALSE);
+
+  /* first sibling -- look at parent */
+  if (node->prev == NULL)
+    {
+      GNode *parent;
+
+      parent = node->parent;
+      switch (NODE_INFO(parent)->type)
+	{
+	case EGG_MENU_MERGE_TOOLBAR:
+	  toolbar = NODE_INFO(parent)->proxy;
+	  pos = 0;
+	  break;
+	case EGG_MENU_MERGE_TOOLBAR_PLACEHOLDER:
+	  toolbar = gtk_widget_get_parent(NODE_INFO(parent)->proxy);
+	  g_return_val_if_fail(EGG_IS_TOOLBAR(toolbar), FALSE);
+	  pos = g_list_index(egg_toolbar_get_tool_items(EGG_TOOLBAR(toolbar)),
+			     NODE_INFO(parent)->proxy) + 1;
+	  break;
+	default:
+	  g_warning("%s: bad parent node type %d", G_STRLOC,
+		    NODE_INFO(parent)->type);
+	  return FALSE;
+	}
+    }
+  else
+    {
+      GtkWidget *prev_child;
+      GNode *sibling;
+
+      sibling = node->prev;
+      if (NODE_INFO(sibling)->type == EGG_MENU_MERGE_TOOLBAR_PLACEHOLDER)
+	prev_child = NODE_INFO(sibling)->extra; /* second Separator */
+      else
+	prev_child = NODE_INFO(sibling)->proxy;
+
+      g_return_val_if_fail(GTK_IS_WIDGET(prev_child), FALSE);
+      toolbar = gtk_widget_get_parent(prev_child);
+      g_return_val_if_fail(EGG_IS_TOOLBAR(toolbar), FALSE);
+
+      pos = g_list_index(egg_toolbar_get_tool_items(EGG_TOOLBAR(toolbar)),
+                         prev_child) + 1;
+    }
+
+  if (toolbar_p)
+    *toolbar_p = toolbar;
+  if (pos_p)
+    *pos_p = pos;
+
+  return TRUE;
+}
+
+static void
+update_node (EggMenuMerge *self, GNode *node)
+{
+  EggMenuMergeNode *info;
+  GNode *child;
+  EggAction *action;
+  GList *tmp;
+
+  g_return_if_fail (node != NULL);
+  g_return_if_fail (NODE_INFO(node) != NULL);
+
+  info = NODE_INFO(node);
+
+  if (NODE_INFO(node)->dirty)
+    {
+      const gchar *action_name;
+      NodeUIReference *ref;
+
+      if (info->uifiles == NULL) {
+	/* We may need to remove this node.
+	 * This must be done in post order
+	 */
+	goto recurse_children;
+      }
+
+      ref = info->uifiles->data;
+      action_name = g_quark_to_string (ref->action_quark);
+      action = get_action_by_name (self, action_name);
+
+      NODE_INFO(node)->dirty = FALSE;
+
+      /* Check if the node doesn't have an action and must have an action */
+      if (action == NULL &&
+	  info->type != EGG_MENU_MERGE_MENUBAR &&
+	  info->type != EGG_MENU_MERGE_TOOLBAR &&
+	  info->type != EGG_MENU_MERGE_SEPARATOR &&
+	  info->type != EGG_MENU_MERGE_MENU_PLACEHOLDER &&
+	  info->type != EGG_MENU_MERGE_TOOLBAR_PLACEHOLDER)
+	{
+	  /* FIXME: Should we warn here? */
+	  goto recurse_children;
+	}
+
+      /* If the widget already has a proxy and the action hasn't changed, then
+       * we don't have to do anything.
+       */
+      if (info->proxy != NULL &&
+	  action == info->action)
+	{
+	  goto recurse_children;
+	}
+      
+      if (info->action)
+	g_object_unref (info->action);
+      info->action = action;
+      if (info->action)
+	g_object_ref (info->action);
+
+      switch (info->type)
+	{
+	case EGG_MENU_MERGE_MENUBAR:
+	  if (info->proxy == NULL)
+	    {
+	      info->proxy = gtk_menu_bar_new ();
+	      gtk_widget_show (info->proxy);
+	      g_signal_emit (self, merge_signals[ADD_WIDGET], 0, info->proxy);
+	    }
+	  break;
+	case EGG_MENU_MERGE_MENU:
+	  {
+	    GtkWidget *prev_submenu = NULL;
+	    /* remove the proxy if it is of the wrong type ... */
+	    if (info->proxy &&  G_OBJECT_TYPE(info->proxy) !=
+		EGG_ACTION_GET_CLASS(info->action)->menu_item_type)
+	      {
+		prev_submenu = gtk_menu_item_get_submenu(GTK_MENU_ITEM(info->proxy));
+		if (prev_submenu)
+		  {
+		    g_object_ref (prev_submenu);
+		    gtk_menu_item_set_submenu(GTK_MENU_ITEM(info->proxy),NULL);
+		  }
+		gtk_container_remove(GTK_CONTAINER(info->proxy->parent),
+				     info->proxy);
+		info->proxy = NULL;
+	    }
+	    /* create proxy if needed ... */
+	    if (info->proxy == NULL)
+	      {
+		GtkWidget *menushell;
+		gint pos;
+		GNode *parent;
+
+		parent = node->parent;
+
+		if (parent && NODE_INFO (parent)->type == EGG_MENU_MERGE_POPUPS)
+		  {
+		    info->proxy = gtk_menu_new();
+		  }
+		else if (find_menu_position(node, &menushell, &pos))
+		  {
+		    GtkWidget *menu;
+		    info->proxy = egg_action_create_menu_item (info->action);
+		    menu = gtk_menu_new();
+		    gtk_menu_item_set_submenu(GTK_MENU_ITEM(info->proxy), menu);
+		    gtk_menu_set_accel_group (GTK_MENU (menu), self->accel_group);
+		    gtk_menu_shell_insert (GTK_MENU_SHELL (menushell),
+					   info->proxy, pos);
+		  }
+	      }
+	    else
+	      {
+		egg_action_connect_proxy (info->action, info->proxy);
+	      }
+	    if (prev_submenu)
+	      {
+		gtk_menu_item_set_submenu (GTK_MENU_ITEM (info->proxy),
+					   prev_submenu);
+		g_object_unref (prev_submenu);
+	      }
+	  }
+	  break;
+	case EGG_MENU_MERGE_UNDECIDED:
+	  g_warning("found 'undecided node!");
+	  break;
+	case EGG_MENU_MERGE_ROOT:
+	  break;
+	case EGG_MENU_MERGE_TOOLBAR:
+	  if (info->proxy == NULL)
+	    {
+	      info->proxy = egg_toolbar_new ();
+	      gtk_widget_show (info->proxy);
+	      g_signal_emit (self, merge_signals[ADD_WIDGET], 0, info->proxy);
+	    }
+	  break;
+	case EGG_MENU_MERGE_MENU_PLACEHOLDER:
+	  /* create menu items for placeholders if necessary ... */
+	  if (!GTK_IS_SEPARATOR_MENU_ITEM (info->proxy) ||
+	      !GTK_IS_SEPARATOR_MENU_ITEM (info->extra))
+	    {
+	      if (info->proxy)
+		gtk_container_remove(GTK_CONTAINER(info->proxy->parent),
+				     info->proxy);
+	      if (info->extra)
+		gtk_container_remove(GTK_CONTAINER(info->extra->parent),
+				     info->extra);
+	      info->proxy = NULL;
+	      info->extra = NULL;
+	    }
+	  if (info->proxy == NULL)
+	    {
+	      GtkWidget *menushell;
+	      gint pos;
+
+	      if (find_menu_position(node, &menushell, &pos))
+		{
+		  NODE_INFO(node)->proxy = gtk_separator_menu_item_new();
+		  gtk_menu_shell_insert(GTK_MENU_SHELL(menushell),
+					NODE_INFO(node)->proxy, pos);
+		  //gtk_widget_show(NODE_INFO(node)->proxy);
+
+		  NODE_INFO(node)->extra = gtk_separator_menu_item_new();
+		  gtk_menu_shell_insert(GTK_MENU_SHELL(menushell),
+					NODE_INFO(node)->extra, pos+1);
+		  //gtk_widget_show(NODE_INFO(node)->extra);
+		}
+	    }
+	  break;
+	case EGG_MENU_MERGE_TOOLBAR_PLACEHOLDER:
+	  /* create toolbar items for placeholders if necessary ... */
+	  if (!EGG_IS_SEPARATOR_TOOL_ITEM (info->proxy) ||
+	      !EGG_IS_SEPARATOR_TOOL_ITEM (info->extra))
+	    {
+	      if (info->proxy)
+		gtk_container_remove(GTK_CONTAINER(info->proxy->parent),
+				     info->proxy);
+	      if (info->extra)
+		gtk_container_remove(GTK_CONTAINER(info->extra->parent),
+				     info->extra);
+	      info->proxy = NULL;
+	      info->extra = NULL;
+	    }
+	  if (info->proxy == NULL)
+	    {
+	      GtkWidget *toolbar;
+	      gint pos;
+
+	      if (find_toolbar_position(node, &toolbar, &pos))
+		{
+		  EggToolItem *item;
+
+		  item = egg_separator_tool_item_new();
+		  egg_toolbar_insert_tool_item(EGG_TOOLBAR(toolbar), item, pos);
+		  NODE_INFO(node)->proxy = GTK_WIDGET (item);
+		  //gtk_widget_show(NODE_INFO(node)->proxy);
+
+		  item = egg_separator_tool_item_new();
+		  egg_toolbar_insert_tool_item(EGG_TOOLBAR(toolbar), item, pos+1);
+		  NODE_INFO(node)->extra = GTK_WIDGET (item);
+		  //gtk_widget_show(NODE_INFO(node)->extra);
+		}
+	    }
+	  break;
+	case EGG_MENU_MERGE_POPUPS:
+	  break;
+	case EGG_MENU_MERGE_MENUITEM:
+	  /* remove the proxy if it is of the wrong type ... */
+	  if (info->proxy &&  G_OBJECT_TYPE(info->proxy) !=
+	      EGG_ACTION_GET_CLASS(info->action)->menu_item_type)
+	    {
+	      gtk_container_remove(GTK_CONTAINER(info->proxy->parent),
+				   info->proxy);
+	      info->proxy = NULL;
+	    }
+	  /* create proxy if needed ... */
+	  if (info->proxy == NULL)
+	    {
+	      GtkWidget *menushell;
+	      gint pos;
+
+	      if (find_menu_position(node, &menushell, &pos))
+		{
+		  info->proxy = egg_action_create_menu_item (info->action);
+
+		  gtk_menu_shell_insert (GTK_MENU_SHELL (menushell),
+					 info->proxy, pos);
+		}
+	    }
+	  else
+	    {
+	      gtk_menu_item_set_submenu(GTK_MENU_ITEM(info->proxy), NULL);
+	      egg_action_connect_proxy (info->action, info->proxy);
+	    }
+	  break;
+	case EGG_MENU_MERGE_TOOLITEM:
+	  /* remove the proxy if it is of the wrong type ... */
+	  if (info->proxy &&  G_OBJECT_TYPE(info->proxy) !=
+	      EGG_ACTION_GET_CLASS(info->action)->toolbar_item_type)
+	    {
+	      gtk_container_remove(GTK_CONTAINER(info->proxy->parent),
+				   info->proxy);
+	      info->proxy = NULL;
+	    }
+	  /* create proxy if needed ... */
+	  if (info->proxy == NULL)
+	    {
+	      GtkWidget *toolbar;
+	      gint pos;
+
+	      if (find_toolbar_position(node, &toolbar, &pos))
+		{
+		  info->proxy = egg_action_create_tool_item (info->action);
+
+		  egg_toolbar_insert_tool_item (EGG_TOOLBAR (toolbar),
+					        EGG_TOOL_ITEM (info->proxy), pos);
+		}
+	    }
+	  else
+	    {
+	      egg_action_connect_proxy (info->action, info->proxy);
+	    }
+	  break;
+	case EGG_MENU_MERGE_SEPARATOR:
+	  if (NODE_INFO (node->parent)->type == EGG_MENU_MERGE_TOOLBAR ||
+	      NODE_INFO (node->parent)->type == EGG_MENU_MERGE_TOOLBAR_PLACEHOLDER)
+	    {
+	      GtkWidget *toolbar;
+	      gint pos;
+
+	      if (EGG_IS_SEPARATOR_TOOL_ITEM(info->proxy))
+		{
+		  gtk_container_remove(GTK_CONTAINER(info->proxy->parent),
+				       info->proxy);
+		  info->proxy = NULL;
+		}
+
+	      if (find_toolbar_position(node, &toolbar, &pos))
+		{
+		  EggToolItem *item = egg_separator_tool_item_new();
+		  egg_toolbar_insert_tool_item (EGG_TOOLBAR (toolbar), item, pos);
+		  info->proxy = GTK_WIDGET (item);
+		  gtk_widget_show(info->proxy);
+		}
+	    }
+	  else
+	    {
+	      GtkWidget *menushell;
+	      gint pos;
+
+	      if (GTK_IS_SEPARATOR_MENU_ITEM(info->proxy))
+		{
+		  gtk_container_remove(GTK_CONTAINER(info->proxy->parent),
+				       info->proxy);
+		  info->proxy = NULL;
+		}
+
+	      if (find_menu_position(node, &menushell, &pos))
+		{
+		  info->proxy = gtk_separator_menu_item_new();
+		  gtk_menu_shell_insert (GTK_MENU_SHELL (menushell),
+					 info->proxy, pos);
+		  gtk_widget_show(info->proxy);
+		}
+	    }
+	  break;
+	}
+
+      /* if this node has a widget, but it is the wrong type, remove it */
+    }
+
+ recurse_children:
+  /* process children */
+  child = node->children;
+  while (child)
+    {
+      GNode *current;
+
+      current = child;
+      child = current->next;
+      update_node (self, current);
+    }
+
+  /* handle cleanup of dead nodes */
+  if (node->children == NULL && NODE_INFO(node)->uifiles == NULL)
+    {
+      if (NODE_INFO(node)->proxy)
+	gtk_widget_destroy(NODE_INFO(node)->proxy);
+      if ((NODE_INFO(node)->type == EGG_MENU_MERGE_MENU_PLACEHOLDER ||
+	   NODE_INFO(node)->type == EGG_MENU_MERGE_TOOLBAR_PLACEHOLDER) &&
+	  NODE_INFO(node)->extra)
+	gtk_widget_destroy(NODE_INFO(node)->extra);
+      g_chunk_free(NODE_INFO(node), merge_node_chunk);
+      g_node_destroy(node);
+    }
+}
+
+static gboolean
+do_updates(EggMenuMerge *self)
+{
+  /* this function needs to check through the tree for dirty nodes.
+   * For such nodes, it needs to do the following:
+   *
+   * 1) check if they are referenced by any loaded UI files anymore.
+   *    In which case, the proxy widget should be destroyed, unless
+   *    there are any subnodes.
+   *
+   * 2) lookup the action for this node again.  If it is different to
+   *    the current one (or if no previous action has been looked up),
+   *    the proxy is reconnected to the new action (or a new proxy widget
+   *    is created and added to the parent container).
+   */
+
+  g_message("do_updates");
+
+  update_node (self, self->root_node);
+
+  self->update_tag = 0;
+  return FALSE;
+}
+
+static void
+egg_menu_merge_queue_update (EggMenuMerge *self)
+{
+  if (self->update_tag != 0)
+    return;
+
+  self->update_tag = g_idle_add((GSourceFunc)do_updates, self);
+}
+
+void
+egg_menu_merge_ensure_update (EggMenuMerge *self)
+{
+  if (self->update_tag != 0)
+    {
+      g_source_remove(self->update_tag);
+      do_updates(self);
+    }
+}
+
+static gboolean
+dirty_traverse_func (GNode *node, gpointer data)
+{
+  NODE_INFO(node)->dirty = TRUE;
+  return FALSE;
+}
+
+static void
+egg_menu_merge_dirty_all (EggMenuMerge *self)
+{
+  g_node_traverse(self->root_node, G_PRE_ORDER, G_TRAVERSE_ALL, -1,
+		  dirty_traverse_func, NULL);
+  egg_menu_merge_queue_update(self);
+}