path: root/src/ephy-session.c

/*
 *  Copyright (C) 2002 Jorn Baayen
 *  Copyright (C) 2003, 2004 Marco Pesenti Gritti
 *  Copyright (C) 2003, 2004 Christian Persch
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2, or (at your option)
 *  any later version.
 *
 *  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 General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 *
 *  $Id$
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "ephy-session.h"

#include "ephy-window.h"
#include "ephy-tab.h"
#include "ephy-shell.h"
#include "ephy-history-window.h"
#include "ephy-bookmarks-editor.h"
#include "ephy-string.h"
#include "ephy-file-helpers.h"
#include "eel-gconf-extensions.h"
#include "ephy-prefs.h"
#include "ephy-debug.h"

#include <glib/gi18n.h>
#include <string.h>
#include <gtk/gtkdialog.h>
#include <gtk/gtkimage.h>
#include <gtk/gtklabel.h>
#include <gtk/gtkstock.h>
#include <gtk/gtkhbox.h>
#include <gtk/gtkvbox.h>
#include <libgnomevfs/gnome-vfs-ops.h>
#include <libxml/tree.h>
#include <libxml/xmlwriter.h>

#define EPHY_SESSION_GET_PRIVATE(object)(G_TYPE_INSTANCE_GET_PRIVATE ((object), EPHY_TYPE_SESSION, EphySessionPrivate))

struct EphySessionPrivate
{
    GList *windows;
    GList *tool_windows;
    GtkWidget *resume_dialog;
    gboolean resuming;
};

#define BOOKMARKS_EDITOR_ID "BookmarksEditor"
#define HISTORY_WINDOW_ID   "HistoryWindow"
#define SESSION_CRASHED     "type:session_crashed"

static void ephy_session_class_init (EphySessionClass *klass);
static void ephy_session_iface_init (EphyExtensionIface *iface);
static void ephy_session_init       (EphySession *session);

enum
{
    PROP_0,
    PROP_ACTIVE_WINDOW
};

static GObjectClass *parent_class = NULL;

GType
ephy_session_get_type (void)
{
    static GType type = 0;

    if (G_UNLIKELY (type == 0))
    {
        static const GTypeInfo our_info =
        {
            sizeof (EphySessionClass),
            NULL, /* base_init */
            NULL, /* base_finalize */
            (GClassInitFunc) ephy_session_class_init,
            NULL,
            NULL, /* class_data */
            sizeof (EphySession),
            0, /* n_preallocs */
            (GInstanceInitFunc) ephy_session_init
        };

        static const GInterfaceInfo extension_info =
        {
            (GInterfaceInitFunc) ephy_session_iface_init,
            NULL,
            NULL
        };

        type = g_type_register_static (G_TYPE_OBJECT,
                           "EphySession",
                           &our_info, 0);

        g_type_add_interface_static (type,
                         EPHY_TYPE_EXTENSION,
                         &extension_info);
    }

    return type;
}

static char *
get_session_filename (const char *filename)
{
    char *save_to;

    if (filename == NULL)
    {
        return NULL;
    }

    if (strcmp (filename, SESSION_CRASHED) == 0)
    {
        save_to = g_build_filename (ephy_dot_dir (),
                        "session_crashed.xml",
                        NULL);
    }
    else
    {
        save_to = g_strdup (filename);
    }

    return save_to;
}

static void
session_delete (EphySession *session,
        const char *filename)
{
    char *save_to;

    save_to = get_session_filename (filename);

    gnome_vfs_unlink (save_to);

    g_free (save_to);
}

static void
net_stop_cb (EphyEmbed *embed,
         EphySession *session)
{
    ephy_session_save (session, SESSION_CRASHED);
}

static void
tab_added_cb (GtkWidget *notebook,
          EphyTab *tab,
          EphySession *session)
{
    g_signal_connect (ephy_tab_get_embed (tab), "net_stop",
              G_CALLBACK (net_stop_cb), session);
}

static void
tab_removed_cb (GtkWidget *notebook,
        EphyTab *tab,
        EphySession *session)
{
    ephy_session_save (session, SESSION_CRASHED);

    g_signal_handlers_disconnect_by_func
        (ephy_tab_get_embed (tab), G_CALLBACK (net_stop_cb), session);
}

static void
tabs_reordered_cb (GtkWidget *notebook,
           EphySession *session)
{
    ephy_session_save (session, SESSION_CRASHED);
}

static gboolean
window_focus_in_event_cb (EphyWindow *window,
              GdkEventFocus *event,
              EphySession *session)
{
    LOG ("focus-in-event for window %p", window)

    g_return_val_if_fail (g_list_find (session->priv->windows, window) != NULL, FALSE);

    /* move the active window to the front of the list */
    session->priv->windows = g_list_remove (session->priv->windows, window);
    session->priv->windows = g_list_prepend (session->priv->windows, window);

    g_object_notify (G_OBJECT (session), "active-window");

    /* propagate event */
    return FALSE;
}

static void
impl_attach_window (EphyExtension *extension,
            EphyWindow *window)
{
    EphySession *session = EPHY_SESSION (extension);
    GtkWidget *notebook;

    LOG ("impl_attach_window")

    session->priv->windows = g_list_append (session->priv->windows, window);
    ephy_session_save (session, SESSION_CRASHED);

    g_signal_connect (window, "focus-in-event",
              G_CALLBACK (window_focus_in_event_cb), session);

    notebook = ephy_window_get_notebook (window);
    g_signal_connect (notebook, "tab_added",
              G_CALLBACK (tab_added_cb), session);
    g_signal_connect (notebook, "tab_removed",
              G_CALLBACK (tab_removed_cb), session);
    g_signal_connect (notebook, "tabs_reordered",
              G_CALLBACK (tabs_reordered_cb), session);
}

static void
impl_detach_window (EphyExtension *extension,
            EphyWindow *window)
{
    EphySession *session = EPHY_SESSION (extension);

    LOG ("impl_detach_window")

    session->priv->windows = g_list_remove (session->priv->windows, window);
    ephy_session_save (session, SESSION_CRASHED);

    /* NOTE: since the window will be destroyed anyway, we don't need to
     * disconnect our signal handlers from its components.
     */
}

static void
ensure_session_directory (void)
{
    char *dir;

    dir = g_build_filename (ephy_dot_dir (), "sessions", NULL);
    if (g_file_test (dir, G_FILE_TEST_EXISTS) == FALSE)
    {
        if (mkdir (dir, 488) != 0)
        {
            g_error ("Unable to create session directory '%s'\n", dir);
        }
    }

    g_free (dir);
}

static void
ephy_session_init (EphySession *session)
{
    session->priv = EPHY_SESSION_GET_PRIVATE (session);

    LOG ("EphySession initialising")

    session->priv->windows = NULL;
    session->priv->tool_windows = NULL;
    session->priv->resume_dialog = NULL;
    session->priv->resuming = FALSE;

    ensure_session_directory ();
}

static void
ephy_session_dispose (GObject *object)
{
    EphySession *session = EPHY_SESSION(object);

    LOG ("EphySession disposing")

    session_delete (session, SESSION_CRASHED);

    parent_class->dispose (object);
}

static void
ephy_session_finalize (GObject *object)
{
    EphySession *session = EPHY_SESSION (object);

    LOG ("EphySession finalising")

    /* FIXME: those should be NULL already!? */
    g_list_free (session->priv->windows);
    g_list_free (session->priv->tool_windows);

    G_OBJECT_CLASS (parent_class)->finalize (object);
}

static void
ephy_session_iface_init (EphyExtensionIface *iface)
{
    iface->attach_window = impl_attach_window;
    iface->detach_window = impl_detach_window;
}

static void
ephy_session_set_property (GObject *object,
               guint prop_id,
               const GValue *value,
               GParamSpec *pspec)
{
    /* no writeable properties */
    g_return_if_reached ();
}

static void
ephy_session_get_property (GObject *object,
               guint prop_id,
               GValue *value,
               GParamSpec *pspec)
{
    EphySession *session = EPHY_SESSION (object);

    switch (prop_id)
    {
        case PROP_ACTIVE_WINDOW:
            g_value_set_object (value, ephy_session_get_active_window (session));
            break;
        default:
            G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
    }
}

static void
ephy_session_class_init (EphySessionClass *class)
{
    GObjectClass *object_class = G_OBJECT_CLASS (class);

    parent_class = g_type_class_peek_parent (class);

    object_class->dispose = ephy_session_dispose;
    object_class->finalize = ephy_session_finalize;
    object_class->get_property = ephy_session_get_property;
    object_class->set_property = ephy_session_set_property;

    g_object_class_install_property
        (object_class,
         PROP_ACTIVE_WINDOW,
         g_param_spec_object ("active-window",
                      "Active Window",
                      "The active window",
                      EPHY_TYPE_WINDOW,
                      G_PARAM_READABLE));

    g_type_class_add_private (object_class, sizeof (EphySessionPrivate));
}

static gboolean
offer_to_resume (EphySession *session)
{
    GtkWidget *dialog;
    GtkWidget *label;
    GtkWidget *vbox;
    GtkWidget *hbox;
    GtkWidget *image;
    char *str;
    int response;

    dialog = gtk_dialog_new_with_buttons
        (_("Crash Recovery"), NULL,
         GTK_DIALOG_NO_SEPARATOR,
         _("_Don't Recover"), GTK_RESPONSE_CANCEL,
         _("_Recover"), GTK_RESPONSE_OK,
         NULL);
    session->priv->resume_dialog = dialog;
    gtk_dialog_set_default_response (GTK_DIALOG (dialog), GTK_RESPONSE_OK);
    gtk_dialog_set_has_separator (GTK_DIALOG (dialog), FALSE);
    gtk_container_set_border_width (GTK_CONTAINER (dialog), 5);
    gtk_box_set_spacing (GTK_BOX (GTK_DIALOG (dialog)->vbox), 14);

    hbox = gtk_hbox_new (FALSE, 6);
    gtk_container_set_border_width (GTK_CONTAINER (GTK_BOX (hbox)), 5);
    gtk_widget_show (hbox);
    gtk_box_pack_start (GTK_BOX (GTK_DIALOG (dialog)->vbox), hbox,
                TRUE, TRUE, 0);

    image = gtk_image_new_from_stock (GTK_STOCK_DIALOG_WARNING,
                      GTK_ICON_SIZE_DIALOG);
    gtk_misc_set_alignment (GTK_MISC (image), 0.5, 0.0);
    gtk_widget_show (image);
    gtk_box_pack_start (GTK_BOX (hbox), image,
                TRUE, TRUE, 0);

    vbox = gtk_vbox_new (FALSE, 6);
    gtk_widget_show (vbox);
    gtk_box_pack_start (GTK_BOX (hbox), vbox,
                TRUE, TRUE, 0);

    label = gtk_label_new (NULL);
    gtk_label_set_selectable (GTK_LABEL (label), TRUE);
    gtk_misc_set_alignment (GTK_MISC (label), 0.0, 0.5);
    gtk_label_set_line_wrap (GTK_LABEL (label), TRUE);
    gtk_widget_show (label);
    str = g_strconcat ("<b>", _("Epiphany appears to have crashed or been killed the last time it was run."),
               "</b>", NULL);
    gtk_label_set_markup (GTK_LABEL (label), str);
    gtk_box_pack_start (GTK_BOX (vbox), label, TRUE, TRUE, 0);
    g_free (str);

    label = gtk_label_new (_("You can recover the opened tabs and windows."));
    gtk_label_set_selectable (GTK_LABEL (label), TRUE);
    gtk_misc_set_alignment (GTK_MISC (label), 0.0, 0.5);
    gtk_widget_show (label);
    gtk_box_pack_start (GTK_BOX (vbox), label,
                TRUE, TRUE, 0);

    response = gtk_dialog_run (GTK_DIALOG (dialog));

    gtk_widget_destroy (dialog);

    session->priv->resume_dialog = NULL;

    return (response == GTK_RESPONSE_OK);
}

/**
 * ephy_session_autoresume:
 * @session: a #EphySession
 *
 * Resume a crashed session when necessary (interactive)
 *
 * Return value: TRUE if handled; windows have actually
 * been opened or the dialog from a previous instance
 * has been re-presented to the user.
 **/
gboolean
ephy_session_autoresume (EphySession *session)
{
    char *saved_session;
    gboolean retval = FALSE;

    LOG ("ephy_session_autoresume")

    if (session->priv->windows != NULL) return FALSE;

    if (session->priv->resume_dialog)
    {
        gtk_window_present (GTK_WINDOW (session->priv->resume_dialog));
        return TRUE;
    }

    saved_session = get_session_filename (SESSION_CRASHED);

    if (g_file_test (saved_session, G_FILE_TEST_EXISTS)
        && offer_to_resume (session))
    {
        session->priv->resuming = TRUE;
        retval = ephy_session_load (session, saved_session);
        session->priv->resuming = FALSE;
        ephy_session_save (session, SESSION_CRASHED);
    }

    g_free (saved_session);

    return retval;
}

void
ephy_session_close (EphySession *session)
{
    GList *windows;

    LOG ("ephy_session_close")

    windows = ephy_session_get_windows (session);
    g_list_foreach (windows, (GFunc) gtk_widget_destroy, NULL);
    g_list_free (windows);

    windows = g_list_copy (session->priv->tool_windows);
    g_list_foreach (windows, (GFunc) gtk_widget_destroy, NULL);
    g_list_free (windows);  
}

static int
write_tab (xmlTextWriterPtr writer,
       EphyTab *tab)
{
    EphyEmbed *embed;
    char *location;
    int ret;

    ret = xmlTextWriterStartElement (writer, (xmlChar *) "embed");
    if (ret < 0) return ret;

    embed = ephy_tab_get_embed (tab);
    location = ephy_embed_get_location (embed, TRUE);
    ret = xmlTextWriterWriteAttribute (writer, (xmlChar *) "url", (xmlChar *) location);
    g_free (location);
    if (ret < 0) return ret;

    ret = xmlTextWriterEndElement (writer); /* embed */
    return ret;
}

static int
write_window_geometry (xmlTextWriterPtr writer,
               GtkWindow *window)
{
    int x = 0, y = 0, width = 0, height = 0;
    int ret;

    /* get window geometry */
    gtk_window_get_size (window, &width, &height);
    gtk_window_get_position (window, &x, &y);

    /* set window properties */
    ret = xmlTextWriterWriteFormatAttribute (writer, (const xmlChar *) "x", "%d", x);
    if (ret < 0) return ret;

    ret = xmlTextWriterWriteFormatAttribute (writer, (const xmlChar *) "y", "%d", y);
    if (ret < 0) return ret;

    ret = xmlTextWriterWriteFormatAttribute (writer, (const xmlChar *) "width", "%d", width);
    if (ret < 0) return ret;

    ret = xmlTextWriterWriteFormatAttribute (writer, (const xmlChar *) "height", "%d", height);
    return ret;
}

static int
write_tool_window (xmlTextWriterPtr writer,
           GtkWindow *window)
{
    const xmlChar *id;
    int ret;

    if (EPHY_IS_BOOKMARKS_EDITOR (window))
    {
        id = (const xmlChar *) BOOKMARKS_EDITOR_ID;
    }
    else if (EPHY_IS_HISTORY_WINDOW (window))
    {
        id = (const xmlChar *) HISTORY_WINDOW_ID;
    }
    else
    {
        g_return_val_if_reached (-1);
    }

    ret = xmlTextWriterStartElement (writer, (const xmlChar *) "toolwindow");
    if (ret < 0) return ret;

    ret = xmlTextWriterWriteAttribute (writer, (const xmlChar *) "id", id);
    if (ret < 0) return ret;

    ret = write_window_geometry (writer, window);
    if (ret < 0) return ret;

    ret = xmlTextWriterEndElement (writer); /* toolwindow */
    return ret;
}

static int
write_ephy_window (xmlTextWriterPtr writer,
           EphyWindow *window)
{
    GList *tabs, *l;
    int ret;

    tabs = ephy_window_get_tabs (window);

    /* Do not save an empty EphyWindow.
     * This only happens when the window was newly opened.
     */
    if (tabs == NULL) return 0;

    ret = xmlTextWriterStartElement (writer, (xmlChar *) "window");
    if (ret < 0) return ret;

    ret = write_window_geometry (writer, GTK_WINDOW (window));
    if (ret < 0) return ret;

    for (l = tabs; l != NULL; l = l->next)
    {
        EphyTab *tab = EPHY_TAB(l->data);
        ret = write_tab (writer, tab);
        if (ret < 0) break;
    }
    g_list_free (tabs);
    if (ret < 0) return ret;

    ret = xmlTextWriterEndElement (writer); /* window */
    return ret;
}

gboolean
ephy_session_save (EphySession *session,
           const char *filename)
{
    xmlTextWriterPtr writer;
    GList *w;
    char *save_to, *tmp_file;
    int ret;

    if (session->priv->resuming)
    {
        return TRUE;
    }

    LOG ("ephy_sesion_save %s", filename)

    if (session->priv->windows == NULL && session->priv->tool_windows == NULL)
    {
        session_delete (session, filename);
        return TRUE;
    }

    save_to = get_session_filename (filename);
    tmp_file = g_strconcat (save_to, ".tmp", NULL);

    /* FIXME: do we want to turn on compression? */
    writer = xmlNewTextWriterFilename (tmp_file, 0);
    if (writer == NULL)
    {
        g_free (save_to);
        g_free (tmp_file);

        return FALSE;
    }

    ret = xmlTextWriterSetIndent (writer, 1);
    if (ret < 0) goto out;

    ret = xmlTextWriterSetIndentString (writer, (const xmlChar *) "  ");
    if (ret < 0) goto out;

    START_PROFILER ("Saving session")

    ret = xmlTextWriterStartDocument (writer, "1.0", NULL, NULL);
    if (ret < 0) goto out;

    /* create and set the root node for the session */
    ret = xmlTextWriterStartElement (writer, (const xmlChar *) "session");
    if (ret < 0) goto out;

    /* iterate through all the windows */   
    for (w = session->priv->windows; w != NULL && ret >= 0; w = w->next)
    {
        ret = write_ephy_window (writer, EPHY_WINDOW (w->data));
    }
    if (ret < 0) goto out;

    for (w = session->priv->tool_windows; w != NULL && ret >= 0; w = w->next)
    {
        ret = write_tool_window (writer, GTK_WINDOW (w->data));
    }
    if (ret < 0) goto out;

    ret = xmlTextWriterEndElement (writer); /* session */
    if (ret < 0) goto out;

    ret = xmlTextWriterEndDocument (writer);

out:
    xmlFreeTextWriter (writer);

    if (ret >= 0)
    {
        if (ephy_file_switch_temp_file (save_to, tmp_file) == FALSE)
        {
            ret = -1;
        }
    }

    g_free (save_to);
    g_free (tmp_file);

    STOP_PROFILER ("Saving session")

    return ret >= 0 ? TRUE : FALSE;
}

static void
parse_embed (xmlNodePtr child, EphyWindow *window)
{
    while (child != NULL)
    {
        if (strcmp ((char *) child->name, "embed") == 0)
        {
            xmlChar *url;

            g_return_if_fail (window != NULL);

            url = xmlGetProp (child, (const xmlChar *) "url");

            ephy_shell_new_tab (ephy_shell, window, NULL, (char *) url,
                        EPHY_NEW_TAB_IN_EXISTING_WINDOW |
                        EPHY_NEW_TAB_OPEN_PAGE |
                        EPHY_NEW_TAB_APPEND_LAST);

            xmlFree (url);
        }

        child = child->next;
    }
}

/*
 * ephy_session_load:
 * @session: a #EphySession
 * @filename: the path of the source file
 *
 * Load a session from disk, restoring the windows and their state
 *
 * Return value: TRUE if at least a window has been opened
 **/
gboolean
ephy_session_load (EphySession *session,
           const char *filename)
{
    xmlDocPtr doc;
        xmlNodePtr child;
    GtkWidget *widget = NULL;
    char *save_to;

    LOG ("ephy_sesion_load %s", filename)

    save_to = get_session_filename (filename);

    doc = xmlParseFile (save_to);
    g_free (save_to);

    if (doc == NULL)
    {
        return FALSE;
    }

    child = xmlDocGetRootElement (doc);

    /* skip the session node */
    child = child->children;

    while (child != NULL)
    {
        if (xmlStrEqual (child->name, (const xmlChar *) "window"))
        {
            widget = GTK_WIDGET (ephy_window_new ());
            parse_embed (child->children, EPHY_WINDOW (widget));
        }
        else if (xmlStrEqual (child->name, (const xmlChar *) "toolwindow"))
        {
            xmlChar *id;

            id = xmlGetProp (child, (const xmlChar *) "id");

            if (id && xmlStrEqual ((const xmlChar *) BOOKMARKS_EDITOR_ID, id))
            {
                if (!eel_gconf_get_boolean (CONF_LOCKDOWN_DISABLE_BOOKMARK_EDITING))
                {
                    widget = ephy_shell_get_bookmarks_editor (ephy_shell);
                }
            }
            else if (id && xmlStrEqual ((const xmlChar *) HISTORY_WINDOW_ID, id))
            {
                if (!eel_gconf_get_boolean (CONF_LOCKDOWN_DISABLE_HISTORY))
                {
                    widget = ephy_shell_get_history_window (ephy_shell);
                }
            }
        }

        if (widget)
        {
            xmlChar *tmp;
            gulong x = 0, y = 0, width = 0, height = 0;

            tmp = xmlGetProp (child, (xmlChar *) "x");
            ephy_string_to_int ((char *) tmp, &x);
            xmlFree (tmp);
            tmp = xmlGetProp (child, (xmlChar *) "y");
            ephy_string_to_int ((char *) tmp, &y);
            xmlFree (tmp);
            tmp = xmlGetProp (child, (xmlChar *) "width");
            ephy_string_to_int ((char *) tmp, &width);
            xmlFree (tmp);
            tmp = xmlGetProp (child, (xmlChar *) "height");
            ephy_string_to_int ((char *) tmp, &height);
            xmlFree (tmp);
            gtk_window_move (GTK_WINDOW (widget), x, y);
            gtk_window_set_default_size (GTK_WINDOW (widget),
                                     width, height);
            gtk_widget_show (widget);
        }

        child = child->next;
    }

    xmlFreeDoc (doc);

    return (session->priv->windows != NULL || session->priv->tool_windows != NULL);
}

/**
 * ephy_session_get_windows:
 * @ephy_session: the #EphySession
 *
 * Returns: the list of open #EphyWindow:s.
 **/
GList *
ephy_session_get_windows (EphySession *session)
{
    g_return_val_if_fail (EPHY_IS_SESSION (session), NULL);

    return g_list_copy (session->priv->windows);
}

/**
 * ephy_session_add_window:
 * @ephy_session: a #EphySession
 * @window: a #EphyWindow
 *
 * Add a tool window to the session. #EphyWindow take care of adding
 * itself to session.
 **/
void
ephy_session_add_window (EphySession *session,
             GtkWindow *window)
{
    LOG ("ephy_session_add_window %p", window)

    session->priv->tool_windows =
        g_list_append (session->priv->tool_windows, window);

    ephy_session_save (session, SESSION_CRASHED);
}

/**
 * ephy_session_remove_window:
 * @session: a #EphySession.
 * @window: a #GtkWindow, which must be either the bookmarks editor or the
 * history window.
 *
 * Remove a tool window from the session.
 **/
void
ephy_session_remove_window (EphySession *session,
                GtkWindow *window)
{
    LOG ("ephy_session_remove_window %p", window)

    session->priv->tool_windows =
        g_list_remove (session->priv->tool_windows, window);

    ephy_session_save (session, SESSION_CRASHED);
}

/**
 * ephy_session_get_active_window:
 * @session: a #EphySession
 *
 * Get the current active browser window. Use it when you
 * need to take an action (like opening an url) on
 * a window but you dont have a target window.
 *
 * Return value: the current active browser window, or NULL of there is none.
 **/
EphyWindow *
ephy_session_get_active_window (EphySession *session)
{
    GList *first;

    g_return_val_if_fail (EPHY_IS_SESSION (session), NULL);

    first = session->priv->windows;
    if (first != NULL)
    {
        return EPHY_WINDOW (first->data);
    }

    return NULL;
}