1 /* GIO - GLib Input, Output and Streaming Library
3 * Copyright (C) 2006-2007 Red Hat, Inc.
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
15 * You should have received a copy of the GNU Lesser General
16 * Public License along with this library; if not, write to the
17 * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
18 * Boston, MA 02111-1307, USA.
20 * Author: Alexander Larsson <alexl@redhat.com>
26 #include "gfilemonitor.h"
27 #include "gio-marshal.h"
28 #include "gioenumtypes.h"
36 typedef struct _FileChange FileChange;
37 static void file_change_free (FileChange *change);
40 * SECTION:gfilemonitor
41 * @short_description: File Monitor
44 * Monitors a file or directory for changes.
46 * To obtain a #GFileMonitor for a file or directory, use
47 * g_file_monitor(), g_file_monitor_file(), or
48 * g_file_monitor_directory().
50 * To get informed about changes to the file or directory you
51 * are monitoring, connect to the #GFileMonitor::changed signal.
54 G_LOCK_DEFINE_STATIC(cancelled);
61 /* work around a limitation of the aliasing foo */
64 G_DEFINE_ABSTRACT_TYPE (GFileMonitor, g_file_monitor, G_TYPE_OBJECT);
68 guint32 last_sent_change_time; /* 0 == not sent */
69 guint32 send_delayed_change_at; /* 0 == never */
70 guint32 send_virtual_changes_done_at; /* 0 == never */
73 struct _GFileMonitorPrivate {
77 /* Rate limiting change events */
78 GHashTable *rate_limiter;
80 GSource *pending_file_change_source;
81 GSList *pending_file_changes; /* FileChange */
84 guint32 timeout_fires_at;
94 g_file_monitor_set_property (GObject *object,
99 GFileMonitor *monitor;
101 monitor = G_FILE_MONITOR (object);
105 case PROP_RATE_LIMIT:
106 g_file_monitor_set_rate_limit (monitor, g_value_get_int (value));
110 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
116 g_file_monitor_get_property (GObject *object,
121 GFileMonitor *monitor;
122 GFileMonitorPrivate *priv;
124 monitor = G_FILE_MONITOR (object);
125 priv = monitor->priv;
129 case PROP_RATE_LIMIT:
130 g_value_set_int (value, priv->rate_limit_msec);
135 g_value_set_boolean (value, priv->cancelled);
136 G_UNLOCK (cancelled);
140 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
145 #define DEFAULT_RATE_LIMIT_MSECS 800
146 #define DEFAULT_VIRTUAL_CHANGES_DONE_DELAY_SECS 2
148 static guint signals[LAST_SIGNAL] = { 0 };
151 rate_limiter_free (RateLimiter *limiter)
153 g_object_unref (limiter->file);
154 g_slice_free (RateLimiter, limiter);
158 g_file_monitor_finalize (GObject *object)
160 GFileMonitor *monitor;
162 monitor = G_FILE_MONITOR (object);
164 if (monitor->priv->timeout)
166 g_source_destroy (monitor->priv->timeout);
167 g_source_unref (monitor->priv->timeout);
170 g_hash_table_destroy (monitor->priv->rate_limiter);
172 G_OBJECT_CLASS (g_file_monitor_parent_class)->finalize (object);
176 g_file_monitor_dispose (GObject *object)
178 GFileMonitor *monitor;
179 GFileMonitorPrivate *priv;
181 monitor = G_FILE_MONITOR (object);
182 priv = monitor->priv;
184 if (priv->pending_file_change_source)
186 g_source_destroy (priv->pending_file_change_source);
187 g_source_unref (priv->pending_file_change_source);
188 priv->pending_file_change_source = NULL;
190 g_slist_foreach (priv->pending_file_changes, (GFunc) file_change_free, NULL);
191 g_slist_free (priv->pending_file_changes);
192 priv->pending_file_changes = NULL;
194 /* Make sure we cancel on last unref */
195 g_file_monitor_cancel (monitor);
197 G_OBJECT_CLASS (g_file_monitor_parent_class)->dispose (object);
201 g_file_monitor_class_init (GFileMonitorClass *klass)
203 GObjectClass *object_class;
205 g_type_class_add_private (klass, sizeof (GFileMonitorPrivate));
207 object_class = G_OBJECT_CLASS (klass);
208 object_class->finalize = g_file_monitor_finalize;
209 object_class->dispose = g_file_monitor_dispose;
210 object_class->get_property = g_file_monitor_get_property;
211 object_class->set_property = g_file_monitor_set_property;
214 * GFileMonitor::changed:
215 * @monitor: a #GFileMonitor.
217 * @other_file: a #GFile.
218 * @event_type: a #GFileMonitorEvent.
220 * Emitted when a file has been changed.
223 g_signal_new (I_("changed"),
226 G_STRUCT_OFFSET (GFileMonitorClass, changed),
228 _gio_marshal_VOID__OBJECT_OBJECT_ENUM,
230 G_TYPE_FILE, G_TYPE_FILE, G_TYPE_FILE_MONITOR_EVENT);
232 g_object_class_install_property (object_class,
234 g_param_spec_int ("rate-limit",
236 P_("The limit of the monitor to watch for changes, in milliseconds"),
238 DEFAULT_RATE_LIMIT_MSECS,
240 G_PARAM_STATIC_NAME|G_PARAM_STATIC_NICK|G_PARAM_STATIC_BLURB));
242 g_object_class_install_property (object_class,
244 g_param_spec_boolean ("cancelled",
246 P_("Whether the monitor has been cancelled"),
249 G_PARAM_STATIC_NAME|G_PARAM_STATIC_NICK|G_PARAM_STATIC_BLURB));
253 g_file_monitor_init (GFileMonitor *monitor)
255 monitor->priv = G_TYPE_INSTANCE_GET_PRIVATE (monitor,
257 GFileMonitorPrivate);
258 monitor->priv->rate_limit_msec = DEFAULT_RATE_LIMIT_MSECS;
259 monitor->priv->rate_limiter = g_hash_table_new_full (g_file_hash, (GEqualFunc)g_file_equal,
260 NULL, (GDestroyNotify) rate_limiter_free);
264 * g_file_monitor_is_cancelled:
265 * @monitor: a #GFileMonitor
267 * Returns whether the monitor is canceled.
269 * Returns: %TRUE if monitor is canceled. %FALSE otherwise.
272 g_file_monitor_is_cancelled (GFileMonitor *monitor)
276 g_return_val_if_fail (G_IS_FILE_MONITOR (monitor), FALSE);
279 res = monitor->priv->cancelled;
280 G_UNLOCK (cancelled);
286 * g_file_monitor_cancel:
287 * @monitor: a #GFileMonitor.
289 * Cancels a file monitor.
291 * Returns: %TRUE if monitor was cancelled.
294 g_file_monitor_cancel (GFileMonitor* monitor)
296 GFileMonitorClass *klass;
298 g_return_val_if_fail (G_IS_FILE_MONITOR (monitor), FALSE);
301 if (monitor->priv->cancelled)
303 G_UNLOCK (cancelled);
307 monitor->priv->cancelled = TRUE;
308 G_UNLOCK (cancelled);
310 g_object_notify (G_OBJECT (monitor), "cancelled");
312 klass = G_FILE_MONITOR_GET_CLASS (monitor);
313 return (* klass->cancel) (monitor);
317 * g_file_monitor_set_rate_limit:
318 * @monitor: a #GFileMonitor.
319 * @limit_msecs: a integer with the limit in milliseconds to
322 * Sets the rate limit to which the @monitor will report
323 * consecutive change events to the same file.
327 g_file_monitor_set_rate_limit (GFileMonitor *monitor,
330 GFileMonitorPrivate *priv;
332 g_return_if_fail (G_IS_FILE_MONITOR (monitor));
334 priv = monitor->priv;
335 if (priv->rate_limit_msec != limit_msecs)
337 monitor->priv->rate_limit_msec = limit_msecs;
338 g_object_notify (G_OBJECT (monitor), "rate-limit");
345 GFileMonitorEvent event_type;
349 file_change_free (FileChange *change)
351 g_object_unref (change->child);
352 if (change->other_file)
353 g_object_unref (change->other_file);
355 g_slice_free (FileChange, change);
359 emit_cb (gpointer data)
361 GFileMonitor *monitor = G_FILE_MONITOR (data);
362 GSList *pending, *iter;
364 pending = g_slist_reverse (monitor->priv->pending_file_changes);
365 monitor->priv->pending_file_changes = NULL;
366 if (monitor->priv->pending_file_change_source)
368 g_source_unref (monitor->priv->pending_file_change_source);
369 monitor->priv->pending_file_change_source = NULL;
372 g_object_ref (monitor);
373 for (iter = pending; iter; iter = iter->next)
375 FileChange *change = iter->data;
376 g_signal_emit (monitor, signals[CHANGED], 0,
377 change->child, change->other_file, change->event_type);
378 file_change_free (change);
380 g_slist_free (pending);
381 g_object_unref (monitor);
387 emit_in_idle (GFileMonitor *monitor,
390 GFileMonitorEvent event_type)
394 GFileMonitorPrivate *priv;
396 priv = monitor->priv;
398 change = g_slice_new (FileChange);
400 change->child = g_object_ref (child);
402 change->other_file = g_object_ref (other_file);
404 change->other_file = NULL;
405 change->event_type = event_type;
407 if (!priv->pending_file_change_source)
409 source = g_idle_source_new ();
410 priv->pending_file_change_source = source;
411 g_source_set_priority (source, 0);
413 /* We don't ref monitor here - instead dispose will free any
416 g_source_set_callback (source, emit_cb, monitor, NULL);
417 g_source_attach (source, NULL);
419 /* We reverse this in the processor */
420 priv->pending_file_changes = g_slist_prepend (priv->pending_file_changes, change);
424 get_time_msecs (void)
426 return g_thread_gettime() / (1000 * 1000);
430 time_difference (guint32 from, guint32 to)
437 /* Change event rate limiting support: */
440 new_limiter (GFileMonitor *monitor,
443 RateLimiter *limiter;
445 limiter = g_slice_new0 (RateLimiter);
446 limiter->file = g_object_ref (file);
447 g_hash_table_insert (monitor->priv->rate_limiter, file, limiter);
453 rate_limiter_send_virtual_changes_done_now (GFileMonitor *monitor,
454 RateLimiter *limiter)
456 if (limiter->send_virtual_changes_done_at != 0)
458 emit_in_idle (monitor, limiter->file, NULL,
459 G_FILE_MONITOR_EVENT_CHANGES_DONE_HINT);
460 limiter->send_virtual_changes_done_at = 0;
465 rate_limiter_send_delayed_change_now (GFileMonitor *monitor,
466 RateLimiter *limiter,
469 if (limiter->send_delayed_change_at != 0)
471 emit_in_idle (monitor,
473 G_FILE_MONITOR_EVENT_CHANGED);
474 limiter->send_delayed_change_at = 0;
475 limiter->last_sent_change_time = time_now;
482 GFileMonitor *monitor;
486 calc_min_time (GFileMonitor *monitor,
487 RateLimiter *limiter,
496 if (limiter->last_sent_change_time != 0)
498 /* Set a timeout at 2*rate limit so that we can clear out the change from the hash eventualy */
499 expire_at = limiter->last_sent_change_time + 2 * monitor->priv->rate_limit_msec;
501 if (time_difference (time_now, expire_at) > 0)
504 *min_time = MIN (*min_time,
505 time_difference (time_now, expire_at));
509 if (limiter->send_delayed_change_at != 0)
512 *min_time = MIN (*min_time,
513 time_difference (time_now, limiter->send_delayed_change_at));
516 if (limiter->send_virtual_changes_done_at != 0)
519 *min_time = MIN (*min_time,
520 time_difference (time_now, limiter->send_virtual_changes_done_at));
527 foreach_rate_limiter_fire (gpointer key,
531 RateLimiter *limiter = value;
532 ForEachData *data = user_data;
534 if (limiter->send_delayed_change_at != 0 &&
535 time_difference (data->time_now, limiter->send_delayed_change_at) == 0)
536 rate_limiter_send_delayed_change_now (data->monitor, limiter, data->time_now);
538 if (limiter->send_virtual_changes_done_at != 0 &&
539 time_difference (data->time_now, limiter->send_virtual_changes_done_at) == 0)
540 rate_limiter_send_virtual_changes_done_now (data->monitor, limiter);
542 return calc_min_time (data->monitor, limiter, data->time_now, &data->min_time);
546 rate_limiter_timeout (gpointer timeout_data)
548 GFileMonitor *monitor = timeout_data;
552 data.min_time = G_MAXUINT32;
553 data.monitor = monitor;
554 data.time_now = get_time_msecs ();
555 g_hash_table_foreach_remove (monitor->priv->rate_limiter,
556 foreach_rate_limiter_fire,
559 /* Remove old timeout */
560 if (monitor->priv->timeout)
562 g_source_destroy (monitor->priv->timeout);
563 g_source_unref (monitor->priv->timeout);
564 monitor->priv->timeout = NULL;
565 monitor->priv->timeout_fires_at = 0;
568 /* Set up new timeout */
569 if (data.min_time != G_MAXUINT32)
571 source = g_timeout_source_new (data.min_time + 1); /* + 1 to make sure we've really passed the time */
572 g_source_set_callback (source, rate_limiter_timeout, monitor, NULL);
573 g_source_attach (source, NULL);
575 monitor->priv->timeout = source;
576 monitor->priv->timeout_fires_at = data.time_now + data.min_time;
583 foreach_rate_limiter_update (gpointer key,
587 RateLimiter *limiter = value;
588 ForEachData *data = user_data;
590 return calc_min_time (data->monitor, limiter, data->time_now, &data->min_time);
594 update_rate_limiter_timeout (GFileMonitor *monitor,
600 if (monitor->priv->timeout_fires_at != 0 && new_time != 0 &&
601 time_difference (new_time, monitor->priv->timeout_fires_at) == 0)
602 return; /* Nothing to do, we already fire earlier than that */
604 data.min_time = G_MAXUINT32;
605 data.monitor = monitor;
606 data.time_now = get_time_msecs ();
607 g_hash_table_foreach_remove (monitor->priv->rate_limiter,
608 foreach_rate_limiter_update,
611 /* Remove old timeout */
612 if (monitor->priv->timeout)
614 g_source_destroy (monitor->priv->timeout);
615 g_source_unref (monitor->priv->timeout);
616 monitor->priv->timeout_fires_at = 0;
617 monitor->priv->timeout = NULL;
620 /* Set up new timeout */
621 if (data.min_time != G_MAXUINT32)
623 source = g_timeout_source_new (data.min_time + 1); /* + 1 to make sure we've really passed the time */
624 g_source_set_callback (source, rate_limiter_timeout, monitor, NULL);
625 g_source_attach (source, NULL);
627 monitor->priv->timeout = source;
628 monitor->priv->timeout_fires_at = data.time_now + data.min_time;
633 * g_file_monitor_emit_event:
634 * @monitor: a #GFileMonitor.
636 * @other_file: a #GFile.
637 * @event_type: a set of #GFileMonitorEvent flags.
639 * Emits the #GFileMonitor::changed signal if a change
640 * has taken place. Should be called from file monitor
641 * implementations only.
643 * The signal will be emitted from an idle handler.
646 g_file_monitor_emit_event (GFileMonitor *monitor,
649 GFileMonitorEvent event_type)
651 guint32 time_now, since_last;
653 RateLimiter *limiter;
655 g_return_if_fail (G_IS_FILE_MONITOR (monitor));
656 g_return_if_fail (G_IS_FILE (child));
658 limiter = g_hash_table_lookup (monitor->priv->rate_limiter, child);
660 if (event_type != G_FILE_MONITOR_EVENT_CHANGED)
664 rate_limiter_send_delayed_change_now (monitor, limiter, get_time_msecs ());
665 if (event_type == G_FILE_MONITOR_EVENT_CHANGES_DONE_HINT)
666 limiter->send_virtual_changes_done_at = 0;
668 rate_limiter_send_virtual_changes_done_now (monitor, limiter);
669 update_rate_limiter_timeout (monitor, 0);
671 emit_in_idle (monitor, child, other_file, event_type);
675 /* Changed event, rate limit */
676 time_now = get_time_msecs ();
681 since_last = time_difference (limiter->last_sent_change_time, time_now);
682 if (since_last < monitor->priv->rate_limit_msec)
684 /* We ignore this change, but arm a timer so that we can fire it later if we
685 don't get any other events (that kill this timeout) */
687 if (limiter->send_delayed_change_at == 0)
689 limiter->send_delayed_change_at = time_now + monitor->priv->rate_limit_msec;
690 update_rate_limiter_timeout (monitor, limiter->send_delayed_change_at);
696 limiter = new_limiter (monitor, child);
700 emit_in_idle (monitor, child, other_file, event_type);
702 limiter->last_sent_change_time = time_now;
703 limiter->send_delayed_change_at = 0;
704 /* Set a timeout of 2*rate limit so that we can clear out the change from the hash eventualy */
705 update_rate_limiter_timeout (monitor, time_now + 2 * monitor->priv->rate_limit_msec);
708 /* Schedule a virtual change done. This is removed if we get a real one, and
709 postponed if we get more change events. */
711 limiter->send_virtual_changes_done_at = time_now + DEFAULT_VIRTUAL_CHANGES_DONE_DELAY_SECS * 1000;
712 update_rate_limiter_timeout (monitor, limiter->send_virtual_changes_done_at);
716 #define __G_FILE_MONITOR_C__
717 #include "gioaliasdef.c"