gtk2/gtk/gtktrashmonitor.c
Ondrej Holy cb9b7278d6 trash-monitor: Rate limit updates
Trash monitor queries info from gvfsd-trash after each file monitor
change which can be problematic when too many changes happen in
a short time. Let's rate limit the number of queries...

Fixes: #1010
2020-05-21 21:16:20 -04:00

286 lines
7.5 KiB
C

/* GTK - The GIMP Toolkit
* gtktrashmonitor.h: Monitor the trash:/// folder to see if there is trash or not
* Copyright (C) 2011 Suse
*
* 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 2.1 of the
* License, 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*
* Authors: Federico Mena Quintero <federico@gnome.org>
*/
#include "config.h"
#include "gtkintl.h"
#include "gtkmarshalers.h"
#include "gtktrashmonitor.h"
#define UPDATE_RATE_SECONDS 1
struct _GtkTrashMonitor
{
GObject parent;
GFileMonitor *file_monitor;
gulong file_monitor_changed_id;
gboolean pending;
gint timeout_id;
guint has_trash : 1;
};
struct _GtkTrashMonitorClass
{
GObjectClass parent_class;
void (* trash_state_changed) (GtkTrashMonitor *monitor);
};
enum {
TRASH_STATE_CHANGED,
LAST_SIGNAL
};
static guint signals[LAST_SIGNAL];
G_DEFINE_TYPE (GtkTrashMonitor, _gtk_trash_monitor, G_TYPE_OBJECT)
static GtkTrashMonitor *the_trash_monitor;
#define ICON_NAME_TRASH_EMPTY "user-trash-symbolic"
#define ICON_NAME_TRASH_FULL "user-trash-full-symbolic"
static void
gtk_trash_monitor_dispose (GObject *object)
{
GtkTrashMonitor *monitor;
monitor = GTK_TRASH_MONITOR (object);
if (monitor->file_monitor)
{
g_signal_handler_disconnect (monitor->file_monitor, monitor->file_monitor_changed_id);
monitor->file_monitor_changed_id = 0;
g_clear_object (&monitor->file_monitor);
}
if (monitor->timeout_id > 0)
g_source_remove (monitor->timeout_id);
monitor->timeout_id = 0;
G_OBJECT_CLASS (_gtk_trash_monitor_parent_class)->dispose (object);
}
static void
_gtk_trash_monitor_class_init (GtkTrashMonitorClass *class)
{
GObjectClass *gobject_class;
gobject_class = (GObjectClass *) class;
gobject_class->dispose = gtk_trash_monitor_dispose;
signals[TRASH_STATE_CHANGED] =
g_signal_new (I_("trash-state-changed"),
G_OBJECT_CLASS_TYPE (gobject_class),
G_SIGNAL_RUN_FIRST,
G_STRUCT_OFFSET (GtkTrashMonitorClass, trash_state_changed),
NULL, NULL,
NULL,
G_TYPE_NONE, 0);
}
/* Updates the internal has_trash flag and emits the "trash-state-changed" signal */
static void
update_has_trash_and_notify (GtkTrashMonitor *monitor,
gboolean has_trash)
{
if (monitor->has_trash == !!has_trash)
return;
monitor->has_trash = !!has_trash;
g_signal_emit (monitor, signals[TRASH_STATE_CHANGED], 0);
}
/* Use G_FILE_ATTRIBUTE_TRASH_ITEM_COUNT since we only want to know whether the
* trash is empty or not, not access its children. This is available for the
* trash backend since it uses a cache. In this way we prevent flooding the
* trash backend with enumeration requests when trashing > 1000 files
*/
static void
trash_query_info_cb (GObject *source,
GAsyncResult *result,
gpointer user_data)
{
GtkTrashMonitor *monitor = GTK_TRASH_MONITOR (user_data);
GFileInfo *info;
guint32 item_count;
gboolean has_trash = FALSE;
info = g_file_query_info_finish (G_FILE (source), result, NULL);
if (info != NULL)
{
item_count = g_file_info_get_attribute_uint32 (info,
G_FILE_ATTRIBUTE_TRASH_ITEM_COUNT);
has_trash = item_count > 0;
g_object_unref (info);
}
update_has_trash_and_notify (monitor, has_trash);
g_object_unref (monitor); /* was reffed in recompute_trash_state() */
}
static void recompute_trash_state (GtkTrashMonitor *monitor);
static gboolean
recompute_trash_state_cb (gpointer data)
{
GtkTrashMonitor *monitor = data;
monitor->timeout_id = 0;
if (monitor->pending)
{
monitor->pending = FALSE;
recompute_trash_state (monitor);
}
return G_SOURCE_REMOVE;
}
/* Asynchronously recomputes whether there is trash or not */
static void
recompute_trash_state (GtkTrashMonitor *monitor)
{
GFile *file;
/* Rate limit the updates to not flood the gvfsd-trash when too many changes
* happended in a short time.
*/
if (monitor->timeout_id > 0)
{
monitor->pending = TRUE;
return;
}
file = g_file_new_for_uri ("trash:///");
g_file_query_info_async (file,
G_FILE_ATTRIBUTE_TRASH_ITEM_COUNT,
G_FILE_QUERY_INFO_NONE,
G_PRIORITY_DEFAULT, NULL,
trash_query_info_cb, g_object_ref (monitor));
monitor->timeout_id = g_timeout_add_seconds (UPDATE_RATE_SECONDS,
recompute_trash_state_cb,
monitor);
g_object_unref (file);
}
/* Callback used when the "trash:///" file monitor changes; we just recompute the trash state
* whenever something happens.
*/
static void
file_monitor_changed_cb (GFileMonitor *file_monitor,
GFile *child,
GFile *other_file,
GFileMonitorEvent event_type,
GtkTrashMonitor *monitor)
{
recompute_trash_state (monitor);
}
static void
_gtk_trash_monitor_init (GtkTrashMonitor *monitor)
{
GFile *file;
file = g_file_new_for_uri ("trash:///");
monitor->file_monitor = g_file_monitor_file (file, G_FILE_MONITOR_NONE, NULL, NULL);
monitor->pending = FALSE;
monitor->timeout_id = 0;
g_object_unref (file);
if (monitor->file_monitor)
monitor->file_monitor_changed_id = g_signal_connect (monitor->file_monitor, "changed",
G_CALLBACK (file_monitor_changed_cb), monitor);
recompute_trash_state (monitor);
}
/**
* _gtk_trash_monitor_get:
*
* Returns: (transfer full): a new reference to the singleton
* #GtkTrashMonitor object. Be sure to call g_object_unref() on it when you are
* done with the trash monitor.
*/
GtkTrashMonitor *
_gtk_trash_monitor_get (void)
{
if (the_trash_monitor != NULL)
{
g_object_ref (the_trash_monitor);
}
else
{
the_trash_monitor = g_object_new (GTK_TYPE_TRASH_MONITOR, NULL);
g_object_add_weak_pointer (G_OBJECT (the_trash_monitor), (gpointer *) &the_trash_monitor);
}
return the_trash_monitor;
}
/**
* _gtk_trash_monitor_get_icon:
* @monitor: a #GtkTrashMonitor
*
* Returns: (transfer full): the #GIcon that should be used to represent
* the state of the trash folder on screen, based on whether there is trash or
* not.
*/
GIcon *
_gtk_trash_monitor_get_icon (GtkTrashMonitor *monitor)
{
const char *icon_name;
g_return_val_if_fail (GTK_IS_TRASH_MONITOR (monitor), NULL);
if (monitor->has_trash)
icon_name = ICON_NAME_TRASH_FULL;
else
icon_name = ICON_NAME_TRASH_EMPTY;
return g_themed_icon_new (icon_name);
}
/**
* _gtk_trash_monitor_get_has_trash:
* @monitor: a #GtkTrashMonitor
*
* Returns: #TRUE if there is trash in the trash:/// folder, or #FALSE otherwise.
*/
gboolean
_gtk_trash_monitor_get_has_trash (GtkTrashMonitor *monitor)
{
g_return_val_if_fail (GTK_IS_TRASH_MONITOR (monitor), FALSE);
return monitor->has_trash;
}