aboutsummaryrefslogblamecommitdiffstats
path: root/e-util/e-tree-model.c
blob: f51c31f66fd0e5a694566ee40d59e8c2c2dcd838 (plain) (tree)
1
2
3
4
5
6
7
8
9
10
  



                                                                
  



                                                                    
  
                                                                   
                                                                             
  
  





                                                        
   
 
                    
                   
      
 

                         
                  
                   


                   
                    

                             
 

                        
 
                                                
 

            
                                                       

      
                   
                     
                          

                      
                     
                              
                


                   
                                          
 
           
                                                
 
                                                            
 








                                                              




























                                                                     









































                                                                         
 



                                            
                                            





























                                            


                                            



                                            

 




                                          

             

   
                           
               

                
    
    
                                                
 
                                                        
 
                                                           

 
   

                        



                
                                             
 

                                                        
                                                        

   
                             
               
         



                

    
                                                  
                                          
 
                                                        
 
                                                                   

 
   
                                  
               
         



                
    
    
                                                       
                                               
 
                                                        
 
                                                                        

 
   
                              
               

                  

  
    
    
                                                   

                                                    
 
                                                        
 

                                                      
                                            

 
   
                             
               

                 

  
    
    
                                                  

                                                  
                                             
 
                                                        
 

                                                     
                                                         
 
 

                             
               
                 

  

    
                                                  
                                                  
 
                                                        
 
                                                                           

 

                                      
               
                   

  

    
                                                           
                                                             
 
                                                        
 
                                                                                      

 






                                                 
            
                       
 
                                                      

 

                        
                                                              
  
                                             


                                                               
         
                                              
 
                                                                  
 

                                                                     

                            

 
   
                                
               




                
    
         

                                                     
 
                                                                  
 

                                                                             

                            

 
   
                                     

               



                
    
         

                                                          
 
                                                                  
 

                                                                                  

                            

 
   
                              

               



                
    
         

                                                   
 
                                                                  
 

                                                                           

                            

 
   
                             
               




                
    
        

                                                  
 
                                                         
 

                                                                          

                             

 
   
                                   
               




                
    
        

                                                        
 

                                                         
 

                                                                                

                             

 
     


                                                       
 


                                                                                      

                         

 
   
                           
               




                
    
     

                                                
 
                                                               
 

                                                                        





                         
                               






                                                              

                                             
 
                                                                  
 

                                                                          
            
                            

 

                                    
                               





                                                              
                                                          
 
                                                                   
 

                                                                                 

                             
 
 

                            
                               





                                       
                                                  
 
                                                               
 

                                                                         

                         

 
   
                           
                               




                                                           
        
                                                 
 
                                                                   
 

                                                                        
            
                             
 
 

                           

                               





                                            

                                                 
 
                                                                  
 

                                                                              

                            

 
   
                                  
                               





                                                                            
                                                        
 
                                                                   
 

                                                                               





                              

                               








                                                                 
                                                    
                                                  
 
                                                                  
 

                                                                                    





                                  
                               





                                                           
                                                        
 
                                                                   
 

                                                                               




                             
                              

                                                                
                                         
  
                                                                      
                                                                         

                                                                 
                                                                      








                                                                      
        

                                                   
                                     
 
                                                                  
 

                                                                                     




                            
                         

                                                                
                                         
  
                                                                      
                                                                         
                                                                 
  
                                                            
  






                                                                      
        

                                              
                                
 
                                                                  
 

                                                                                
            
                            
 
 
    

                                                  

                                             
 
                                                        
 

                                                                                  

 
   
                                 
               




                
    
        

                                                      
                                        
 
                                                         
 

                                                                                   
            
                             

 
   
                                


               


                
    
        
                                                     

                                                  
 
                                                        
 

                                                                                        

                            
 
 
   
                           


               


                
    
    
                                                

                                        
 
                                              
 

                                                                            

 

                                 

               



                
    
        
                                                      
                                        
 
                                                        
 

                                                                                  

                            

 
   
                               


               


                
    
        
                                                    

                                                 
 
                                                        
 

                                                                                       


                            
 

                                


               


                
    
       
                                                     

                                                  
 
                                                                 
 

                                                                                        
            
                                     
 


                              
               




         

    
                                                   


                                               


                        
                                                        

                                        
                                                                     



                                     


                                                                            





                                   
                


                                                    

                                                    


                        


                                                             
                                                                

                       

                                 
                                                                   

                                     
                                                               
                                                             

                                      
                                                                  
         
 



                    

                          
         
             



         

         
                                               

                                           

                                           



                         
                                                                  



                                                      
                                                          
 
                                                                      

                                    
                                                          
                                                                
                           

                                      


                            
                   
 



                                                                     
 
                                      
                                                                               
 

                                            
 
                                                                             
                 
 
                                                                      
                                    
 
                            
         

 
/*
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) version 3.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with the program; if not, see <http://www.gnu.org/licenses/>
 *
 *
 * Authors:
 *      Chris Lahey  <clahey@ximian.com>
 *      Chris Toshok <toshok@ximian.com>
 *
 * Copyright (C) 1999-2008 Novell, Inc. (www.novell.com)
 *
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include "e-tree-model.h"

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>

#include <gtk/gtk.h>
#include <libxml/parser.h>
#include <libxml/xmlmemory.h>

#include "e-marshal.h"
#include "e-xml-utils.h"

#define ETM_CLASS(e) (E_TREE_MODEL_GET_CLASS(e))

#define d(x)

G_DEFINE_TYPE (ETreeModel, e_tree_model, G_TYPE_OBJECT)

enum {
    PRE_CHANGE,
    NODE_CHANGED,
    NODE_DATA_CHANGED,
    NODE_INSERTED,
    NODE_REMOVED,
    NODE_DELETED,
    NODE_REQUEST_COLLAPSE,
    REBUILT,
    LAST_SIGNAL
};

static guint signals[LAST_SIGNAL] = {0, };

static void
e_tree_model_class_init (ETreeModelClass *class)
{
    GObjectClass *object_class = G_OBJECT_CLASS (class);

    signals[PRE_CHANGE] = g_signal_new (
        "pre_change",
        G_TYPE_FROM_CLASS (object_class),
        G_SIGNAL_RUN_LAST,
        G_STRUCT_OFFSET (ETreeModelClass, pre_change),
        (GSignalAccumulator) NULL, NULL,
        g_cclosure_marshal_VOID__VOID,
        G_TYPE_NONE, 0);

    signals[REBUILT] = g_signal_new (
        "rebuilt",
        G_TYPE_FROM_CLASS (object_class),
        G_SIGNAL_RUN_LAST,
        G_STRUCT_OFFSET (ETreeModelClass, rebuilt),
        (GSignalAccumulator) NULL, NULL,
        g_cclosure_marshal_VOID__VOID,
        G_TYPE_NONE, 0);

    signals[NODE_CHANGED] = g_signal_new (
        "node_changed",
        G_TYPE_FROM_CLASS (object_class),
        G_SIGNAL_RUN_LAST,
        G_STRUCT_OFFSET (ETreeModelClass, node_changed),
        (GSignalAccumulator) NULL, NULL,
        g_cclosure_marshal_VOID__POINTER,
        G_TYPE_NONE, 1,
        G_TYPE_POINTER);

    signals[NODE_DATA_CHANGED] = g_signal_new (
        "node_data_changed",
        G_TYPE_FROM_CLASS (object_class),
        G_SIGNAL_RUN_LAST,
        G_STRUCT_OFFSET (ETreeModelClass, node_data_changed),
        (GSignalAccumulator) NULL, NULL,
        g_cclosure_marshal_VOID__POINTER,
        G_TYPE_NONE, 1,
        G_TYPE_POINTER);

    signals[NODE_INSERTED] = g_signal_new (
        "node_inserted",
        G_TYPE_FROM_CLASS (object_class),
        G_SIGNAL_RUN_LAST,
        G_STRUCT_OFFSET (ETreeModelClass, node_inserted),
        (GSignalAccumulator) NULL, NULL,
        e_marshal_VOID__POINTER_POINTER,
        G_TYPE_NONE, 2,
        G_TYPE_POINTER,
        G_TYPE_POINTER);

    signals[NODE_REMOVED] = g_signal_new (
        "node_removed",
        G_TYPE_FROM_CLASS (object_class),
        G_SIGNAL_RUN_LAST,
        G_STRUCT_OFFSET (ETreeModelClass, node_removed),
        (GSignalAccumulator) NULL, NULL,
        e_marshal_VOID__POINTER_POINTER_INT,
        G_TYPE_NONE, 3,
        G_TYPE_POINTER,
        G_TYPE_POINTER,
        G_TYPE_INT);

    signals[NODE_DELETED] = g_signal_new (
        "node_deleted",
        G_TYPE_FROM_CLASS (object_class),
        G_SIGNAL_RUN_LAST,
        G_STRUCT_OFFSET (ETreeModelClass, node_deleted),
        (GSignalAccumulator) NULL, NULL,
        g_cclosure_marshal_VOID__POINTER,
        G_TYPE_NONE, 1,
        G_TYPE_POINTER);

    signals[NODE_REQUEST_COLLAPSE] = g_signal_new (
        "node_request_collapse",
        G_TYPE_FROM_CLASS (object_class),
        G_SIGNAL_RUN_LAST,
        G_STRUCT_OFFSET (ETreeModelClass, node_request_collapse),
        (GSignalAccumulator) NULL, NULL,
        g_cclosure_marshal_VOID__POINTER,
        G_TYPE_NONE, 1,
        G_TYPE_POINTER);

    class->get_root              = NULL;

    class->get_parent            = NULL;
    class->get_first_child       = NULL;
    class->get_next              = NULL;

    class->is_root               = NULL;
    class->is_expandable         = NULL;
    class->get_children          = NULL;
    class->depth                 = NULL;

    class->icon_at               = NULL;

    class->get_expanded_default  = NULL;
    class->column_count          = NULL;

    class->has_save_id           = NULL;
    class->get_save_id           = NULL;
    class->has_get_node_by_id    = NULL;
    class->get_node_by_id        = NULL;

    class->has_change_pending    = NULL;

    class->sort_value_at      = NULL;
    class->value_at              = NULL;
    class->set_value_at          = NULL;
    class->is_editable           = NULL;

    class->duplicate_value       = NULL;
    class->free_value            = NULL;
    class->initialize_value      = NULL;
    class->value_is_empty        = NULL;
    class->value_to_string       = NULL;

    class->pre_change            = NULL;
    class->rebuilt           = NULL;
    class->node_changed          = NULL;
    class->node_data_changed     = NULL;
    class->node_inserted         = NULL;
    class->node_removed          = NULL;
    class->node_deleted          = NULL;
    class->node_request_collapse = NULL;
}

static void
e_tree_model_init (ETreeModel *tree_model)
{
    /* nothing to do */
}

/* signals */

/**
 * e_tree_model_pre_change:
 * @tree_model:
 *
 * Return value:
 **/
void
e_tree_model_pre_change (ETreeModel *tree_model)
{
    g_return_if_fail (E_IS_TREE_MODEL (tree_model));

    g_signal_emit (tree_model, signals[PRE_CHANGE], 0);
}

/**
 * e_tree_model_rebuilt:
 * @tree_model:
 *
 * Return value:
 **/
void
e_tree_model_rebuilt (ETreeModel *tree_model)
{
    g_return_if_fail (E_IS_TREE_MODEL (tree_model));

    g_signal_emit (tree_model, signals[REBUILT], 0);
}
/**
 * e_tree_model_node_changed:
 * @tree_model:
 * @path:
 *
 *
 *
 * Return value:
 **/
void
e_tree_model_node_changed (ETreeModel *tree_model,
                           ETreePath path)
{
    g_return_if_fail (E_IS_TREE_MODEL (tree_model));

    g_signal_emit (tree_model, signals[NODE_CHANGED], 0, path);
}

/**
 * e_tree_model_node_data_changed:
 * @tree_model:
 * @path:
 *
 *
 *
 * Return value:
 **/
void
e_tree_model_node_data_changed (ETreeModel *tree_model,
                                ETreePath path)
{
    g_return_if_fail (E_IS_TREE_MODEL (tree_model));

    g_signal_emit (tree_model, signals[NODE_DATA_CHANGED], 0, path);
}

/**
 * e_tree_model_node_inserted:
 * @tree_model:
 * @parent_path:
 * @inserted_path:
 *
 *
 **/
void
e_tree_model_node_inserted (ETreeModel *tree_model,
                            ETreePath parent_path,
                            ETreePath inserted_path)
{
    g_return_if_fail (E_IS_TREE_MODEL (tree_model));

    g_signal_emit (
        tree_model, signals[NODE_INSERTED], 0,
        parent_path, inserted_path);
}

/**
 * e_tree_model_node_removed:
 * @tree_model:
 * @parent_path:
 * @removed_path:
 *
 *
 **/
void
e_tree_model_node_removed (ETreeModel *tree_model,
                           ETreePath parent_path,
                           ETreePath removed_path,
                           gint old_position)
{
    g_return_if_fail (E_IS_TREE_MODEL (tree_model));

    g_signal_emit (
        tree_model, signals[NODE_REMOVED], 0,
        parent_path, removed_path, old_position);
}

/**
 * e_tree_model_node_deleted:
 * @tree_model:
 * @deleted_path:
 *
 *
 **/
void
e_tree_model_node_deleted (ETreeModel *tree_model,
                           ETreePath deleted_path)
{
    g_return_if_fail (E_IS_TREE_MODEL (tree_model));

    g_signal_emit (tree_model, signals[NODE_DELETED], 0, deleted_path);
}

/**
 * e_tree_model_node_request_collapse:
 * @tree_model:
 * @collapsed_path:
 *
 *
 **/
void
e_tree_model_node_request_collapse (ETreeModel *tree_model,
                                    ETreePath collapsed_path)
{
    g_return_if_fail (E_IS_TREE_MODEL (tree_model));

    g_signal_emit (tree_model, signals[NODE_REQUEST_COLLAPSE], 0, collapsed_path);
}

/**
 * e_tree_model_new
 *
 * XXX docs here.
 *
 * return values: a newly constructed ETreeModel.
 */
ETreeModel *
e_tree_model_new (void)
{
    return g_object_new (E_TYPE_TREE_MODEL, NULL);
}

/**
 * e_tree_model_get_root
 * @tree_model: the ETreeModel of which we want the root node.
 *
 * Accessor for the root node of @tree_model.
 *
 * return values: the ETreePath corresponding to the root node.
 */
ETreePath
e_tree_model_get_root (ETreeModel *tree_model)
{
    g_return_val_if_fail (E_IS_TREE_MODEL (tree_model), NULL);

    if (ETM_CLASS (tree_model)->get_root)
        return ETM_CLASS (tree_model)->get_root (tree_model);
    else
        return NULL;
}

/**
 * e_tree_model_node_get_parent:
 * @tree_model:
 * @path:
 *
 *
 *
 * Return value:
 **/
ETreePath
e_tree_model_node_get_parent (ETreeModel *tree_model,
                              ETreePath path)
{
    g_return_val_if_fail (E_IS_TREE_MODEL (tree_model), NULL);

    if (ETM_CLASS (tree_model)->get_parent)
        return ETM_CLASS (tree_model)->get_parent (tree_model, path);
    else
        return NULL;
}

/**
 * e_tree_model_node_get_first_child:
 * @tree_model:
 * @path:
 *
 *
 *
 * Return value:
 **/
ETreePath
e_tree_model_node_get_first_child (ETreeModel *tree_model,
                                   ETreePath path)
{
    g_return_val_if_fail (E_IS_TREE_MODEL (tree_model), NULL);

    if (ETM_CLASS (tree_model)->get_first_child)
        return ETM_CLASS (tree_model)->get_first_child (tree_model, path);
    else
        return NULL;
}

/**
 * e_tree_model_node_get_next:
 * @tree_model:
 * @path:
 *
 *
 *
 * Return value:
 **/
ETreePath
e_tree_model_node_get_next (ETreeModel *tree_model,
                            ETreePath path)
{
    g_return_val_if_fail (E_IS_TREE_MODEL (tree_model), NULL);

    if (ETM_CLASS (tree_model)->get_next)
        return ETM_CLASS (tree_model)->get_next (tree_model, path);
    else
        return NULL;
}

/**
 * e_tree_model_node_is_root:
 * @tree_model:
 * @path:
 *
 *
 *
 * Return value:
 **/
gboolean
e_tree_model_node_is_root (ETreeModel *tree_model,
                           ETreePath path)
{
    g_return_val_if_fail (tree_model != NULL, FALSE);

    if (ETM_CLASS (tree_model)->is_root)
        return ETM_CLASS (tree_model)->is_root (tree_model, path);
    else
        return FALSE;
}

/**
 * e_tree_model_node_is_expandable:
 * @tree_model:
 * @path:
 *
 *
 *
 * Return value:
 **/
gboolean
e_tree_model_node_is_expandable (ETreeModel *tree_model,
                                 ETreePath path)
{
    g_return_val_if_fail (tree_model != NULL, FALSE);
    g_return_val_if_fail (path != NULL, FALSE);

    if (ETM_CLASS (tree_model)->is_expandable)
        return ETM_CLASS (tree_model)->is_expandable (tree_model, path);
    else
        return FALSE;
}

guint
e_tree_model_node_get_children (ETreeModel *tree_model,
                                ETreePath path,
                                ETreePath **paths)
{
    g_return_val_if_fail (tree_model != NULL, 0);
    if (ETM_CLASS (tree_model)->get_children)
        return ETM_CLASS (tree_model)->get_children (tree_model, path, paths);
    else
        return 0;
}

/**
 * e_tree_model_node_depth:
 * @tree_model:
 * @path:
 *
 *
 *
 * Return value:
 **/
guint
e_tree_model_node_depth (ETreeModel *tree_model,
                         ETreePath path)
{
    g_return_val_if_fail (E_IS_TREE_MODEL (tree_model), 0);

    if (ETM_CLASS (tree_model)->depth)
        return ETM_CLASS (tree_model)->depth (tree_model, path);
    else
        return 0;
}

/**
 * e_tree_model_icon_at
 * @tree_model: The ETreeModel.
 * @path: The ETreePath to the node we're getting the icon of.
 *
 * XXX docs here.
 *
 * return values: the GdkPixbuf associated with this node.
 */
GdkPixbuf *
e_tree_model_icon_at (ETreeModel *tree_model,
                      ETreePath path)
{
    g_return_val_if_fail (E_IS_TREE_MODEL (tree_model), NULL);

    if (ETM_CLASS (tree_model)->icon_at)
        return ETM_CLASS (tree_model)->icon_at (tree_model, path);
    else
        return NULL;
}

/**
 * e_tree_model_get_expanded_default
 * @tree_model: The ETreeModel.
 *
 * XXX docs here.
 *
 * return values: Whether nodes should be expanded by default.
 */
gboolean
e_tree_model_get_expanded_default (ETreeModel *tree_model)
{
    g_return_val_if_fail (E_IS_TREE_MODEL (tree_model), FALSE);

    if (ETM_CLASS (tree_model)->get_expanded_default)
        return ETM_CLASS (tree_model)->get_expanded_default (tree_model);
    else
        return FALSE;
}

/**
 * e_tree_model_column_count
 * @tree_model: The ETreeModel.
 *
 * XXX docs here.
 *
 * return values: The number of columns
 */
gint
e_tree_model_column_count (ETreeModel *tree_model)
{
    g_return_val_if_fail (E_IS_TREE_MODEL (tree_model), 0);

    if (ETM_CLASS (tree_model)->column_count)
        return ETM_CLASS (tree_model)->column_count (tree_model);
    else
        return 0;
}

/**
 * e_tree_model_has_save_id
 * @tree_model: The ETreeModel.
 *
 * XXX docs here.
 *
 * return values: Whether this tree has valid save id data.
 */
gboolean
e_tree_model_has_save_id (ETreeModel *tree_model)
{
    g_return_val_if_fail (E_IS_TREE_MODEL (tree_model), FALSE);

    if (ETM_CLASS (tree_model)->has_save_id)
        return ETM_CLASS (tree_model)->has_save_id (tree_model);
    else
        return FALSE;
}

/**
 * e_tree_model_get_save_id
 * @tree_model: The ETreeModel.
 * @path: The ETreePath.
 *
 * XXX docs here.
 *
 * return values: The save id for this path.
 */
gchar *
e_tree_model_get_save_id (ETreeModel *tree_model,
                          ETreePath path)
{
    g_return_val_if_fail (E_IS_TREE_MODEL (tree_model), NULL);

    if (ETM_CLASS (tree_model)->get_save_id)
        return ETM_CLASS (tree_model)->get_save_id (tree_model, path);
    else
        return NULL;
}

/**
 * e_tree_model_has_get_node_by_id
 * @tree_model: The ETreeModel.
 *
 * XXX docs here.
 *
 * return values: Whether this tree can quickly get a node from its save id.
 */
gboolean
e_tree_model_has_get_node_by_id (ETreeModel *tree_model)
{
    g_return_val_if_fail (E_IS_TREE_MODEL (tree_model), FALSE);

    if (ETM_CLASS (tree_model)->has_get_node_by_id)
        return ETM_CLASS (tree_model)->has_get_node_by_id (tree_model);
    else
        return FALSE;
}

/**
 * e_tree_model_get_node_by_id
 * @tree_model: The ETreeModel.
 * @save_id:
 *
 * get_node_by_id(get_save_id(node)) should be the original node.
 * Likewise if get_node_by_id is not NULL, then
 * get_save_id(get_node_by_id(string)) should be a copy of the
 * original string.
 *
 * return values: The path for this save id.
 */
ETreePath
e_tree_model_get_node_by_id (ETreeModel *tree_model,
                             const gchar *save_id)
{
    g_return_val_if_fail (E_IS_TREE_MODEL (tree_model), NULL);

    if (ETM_CLASS (tree_model)->get_node_by_id)
        return ETM_CLASS (tree_model)->get_node_by_id (tree_model, save_id);
    else
        return NULL;
}

/**
 * e_tree_model_has_change_pending
 * @tree_model: The ETreeModel.
 *
 * XXX docs here.
 *
 * return values: Whether this tree has valid save id data.
 */
gboolean
e_tree_model_has_change_pending (ETreeModel *tree_model)
{
    g_return_val_if_fail (E_IS_TREE_MODEL (tree_model), FALSE);

    if (ETM_CLASS (tree_model)->has_change_pending)
        return ETM_CLASS (tree_model)->has_change_pending (tree_model);
    else
        return FALSE;
}

/**
 * e_tree_model_sort_value_at:
 * @tree_model: The ETreeModel.
 * @path: The ETreePath to the node we're getting the data from.
 * @col: the column to retrieve data from
 *
 * Return value: This function returns the value that is stored by the
 * @tree_model in column @col and node @path.  The data returned can be a
 * pointer or any data value that can be stored inside a pointer.
 *
 * The data returned is typically used by an sort renderer if it wants
 * to proxy the data of cell value_at at a better sorting order.
 *
 * The data returned must be valid until the model sends a signal that
 * affect that piece of data.  node_changed and node_deleted affect
 * all data in tha t node and all nodes under that node.
 * node_data_changed affects the data in that node.  node_col_changed
 * affects the data in that node for that column.  node_inserted,
 * node_removed, and no_change don't affect any data in this way.
 **/
gpointer
e_tree_model_sort_value_at (ETreeModel *tree_model,
                            ETreePath path,
                            gint col)
{
    g_return_val_if_fail (E_IS_TREE_MODEL (tree_model), NULL);

    if (ETM_CLASS (tree_model)->sort_value_at)
        return ETM_CLASS (tree_model)->sort_value_at (tree_model, path, col);
    else
        return NULL;
}

/**
 * e_tree_model_value_at:
 * @tree_model: The ETreeModel.
 * @path: The ETreePath to the node we're getting the data from.
 * @col: the column to retrieve data from
 *
 * Return value: This function returns the value that is stored by the
 * @tree_model in column @col and node @path.  The data returned can be a
 * pointer or any data value that can be stored inside a pointer.
 *
 * The data returned is typically used by an ECell renderer.
 *
 * The data returned must be valid until the model sends a signal that
 * affect that piece of data.  node_changed and node_deleted affect
 * all data in tha t node and all nodes under that node.
 * node_data_changed affects the data in that node.  node_col_changed
 * affects the data in that node for that column.  node_inserted,
 * node_removed, and no_change don't affect any data in this way.
 **/
gpointer
e_tree_model_value_at (ETreeModel *tree_model,
                       ETreePath path,
                       gint col)
{
    g_return_val_if_fail (E_IS_TREE_MODEL (tree_model), NULL);

    if (ETM_CLASS (tree_model)->value_at)
        return ETM_CLASS (tree_model)->value_at (tree_model, path, col);
    else
        return NULL;
}

void
e_tree_model_set_value_at (ETreeModel *tree_model,
                           ETreePath path,
                           gint col,
                           gconstpointer val)
{
    g_return_if_fail (E_IS_TREE_MODEL (tree_model));

    if (ETM_CLASS (tree_model)->set_value_at)
        ETM_CLASS (tree_model)->set_value_at (tree_model, path, col, val);
}

/**
 * e_tree_model_node_is_editable:
 * @tree_model:
 * @path:
 *
 *
 *
 * Return value:
 **/
gboolean
e_tree_model_node_is_editable (ETreeModel *tree_model,
                               ETreePath path,
                               gint col)
{
    g_return_val_if_fail (tree_model != NULL, FALSE);

    if (ETM_CLASS (tree_model)->is_editable)
        return ETM_CLASS (tree_model)->is_editable (tree_model, path, col);
    else
        return FALSE;
}

/**
 * e_tree_model_duplicate_value:
 * @tree_model:
 * @col:
 * @value:
 *
 *
 * Return value:
 **/
gpointer
e_tree_model_duplicate_value (ETreeModel *tree_model,
                              gint col,
                              gconstpointer value)
{
    g_return_val_if_fail (tree_model != NULL, NULL);

    if (ETM_CLASS (tree_model)->duplicate_value)
        return ETM_CLASS (tree_model)->duplicate_value (tree_model, col, value);
    else
        return NULL;
}

/**
 * e_tree_model_free_value:
 * @tree_model:
 * @col:
 * @value:
 *
 *
 * Return value:
 **/
void
e_tree_model_free_value (ETreeModel *tree_model,
                         gint col,
                         gpointer value)
{
    g_return_if_fail (tree_model != NULL);

    if (ETM_CLASS (tree_model)->free_value)
        ETM_CLASS (tree_model)->free_value (tree_model, col, value);
}

/**
 * e_tree_model_initialize_value:
 * @tree_model:
 * @col:
 *
 *
 *
 * Return value:
 **/
gpointer
e_tree_model_initialize_value (ETreeModel *tree_model,
                               gint col)
{
    g_return_val_if_fail (tree_model != NULL, NULL);

    if (ETM_CLASS (tree_model)->initialize_value)
        return ETM_CLASS (tree_model)->initialize_value (tree_model, col);
    else
        return NULL;
}

/**
 * e_tree_model_value_is_empty:
 * @tree_model:
 * @col:
 * @value:
 *
 *
 * Return value:
 **/
gboolean
e_tree_model_value_is_empty (ETreeModel *tree_model,
                             gint col,
                             gconstpointer value)
{
    g_return_val_if_fail (tree_model != NULL, TRUE);

    if (ETM_CLASS (tree_model)->value_is_empty)
        return ETM_CLASS (tree_model)->value_is_empty (tree_model, col, value);
    else
        return TRUE;
}

/**
 * e_tree_model_value_to_string:
 * @tree_model:
 * @col:
 * @value:
 *
 *
 * Return value:
 **/
gchar *
e_tree_model_value_to_string (ETreeModel *tree_model,
                              gint col,
                              gconstpointer value)
{
    g_return_val_if_fail (tree_model != NULL, g_strdup (""));

    if (ETM_CLASS (tree_model)->value_to_string)
        return ETM_CLASS (tree_model)->value_to_string (tree_model, col, value);
    else
        return g_strdup ("");
}

/**
 * e_tree_model_node_traverse:
 * @tree_model:
 * @path:
 * @func:
 * @data:
 *
 *
 **/
void
e_tree_model_node_traverse (ETreeModel *tree_model,
                            ETreePath path,
                            ETreePathFunc func,
                            gpointer data)
{
    ETreePath child;

    g_return_if_fail (E_IS_TREE_MODEL (tree_model));
    g_return_if_fail (path != NULL);

    child = e_tree_model_node_get_first_child (tree_model, path);

    while (child) {
        ETreePath next_child;

        next_child = e_tree_model_node_get_next (tree_model, child);
        e_tree_model_node_traverse (tree_model, child, func, data);
        if (func (tree_model, child, data))
            return;

        child = next_child;
    }
}

static ETreePath
e_tree_model_node_real_traverse (ETreeModel *model,
                                 ETreePath path,
                                 ETreePath end_path,
                                 ETreePathFunc func,
                                 gpointer data)
{
    ETreePath child;

    g_return_val_if_fail (E_IS_TREE_MODEL (model), NULL);
    g_return_val_if_fail (path != NULL, NULL);

    child = e_tree_model_node_get_first_child (model, path);

    while (child) {
        ETreePath result;

        if (child == end_path || func (model, child, data))
            return child;

        if ((result = e_tree_model_node_real_traverse (
            model, child, end_path, func, data)))
            return result;

        child = e_tree_model_node_get_next (model, child);
    }

    return NULL;
}

/**
 * e_tree_model_node_find:
 * @tree_model:
 * @path:
 * @end_path:
 * @func:
 * @data:
 *
 *
 **/
ETreePath
e_tree_model_node_find (ETreeModel *tree_model,
                        ETreePath path,
                        ETreePath end_path,
                        ETreePathFunc func,
                        gpointer data)
{
    ETreePath result;
    ETreePath next;

    g_return_val_if_fail (E_IS_TREE_MODEL (tree_model), NULL);

    /* Just search the whole tree in this case. */
    if (path == NULL) {
        ETreePath root;
        root = e_tree_model_get_root (tree_model);

        if (end_path == root || func (tree_model, root, data))
            return root;

        result = e_tree_model_node_real_traverse (
            tree_model, root, end_path, func, data);
        if (result)
            return result;

        return NULL;
    }

    while (1) {

        if ((result = e_tree_model_node_real_traverse (
            tree_model, path, end_path, func, data)))
            return result;
        next = e_tree_model_node_get_next (tree_model, path);

        while (next == NULL) {
            path = e_tree_model_node_get_parent (tree_model, path);

            if (path == NULL)
                return NULL;

            next = e_tree_model_node_get_next (tree_model, path);
        }

        if (end_path == next || func (tree_model, next, data))
            return next;

        path = next;
    }
}