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"
35 * SECTION:gfilemonitor
36 * @short_description: File Monitor
39 * Monitors a file or directory for changes.
41 * To obtain a #GFileMonitor for a file or directory, use
42 * g_file_monitor_file() or g_file_monitor_directory().
44 * To get informed about changes to the file or directory you
45 * are monitoring, connect to the #GFileMonitor::changed signal.
48 G_LOCK_DEFINE_STATIC(cancelled);
55 G_DEFINE_ABSTRACT_TYPE (GFileMonitor, g_file_monitor, G_TYPE_OBJECT);
59 guint32 last_sent_change_time; /* 0 == not sent */
60 guint32 send_delayed_change_at; /* 0 == never */
61 guint32 send_virtual_changes_done_at; /* 0 == never */
64 struct _GFileMonitorPrivate {
68 /* Rate limiting change events */
69 GHashTable *rate_limiter;
72 guint32 timeout_fires_at;
82 g_file_monitor_set_property (GObject *object,
87 GFileMonitor *monitor;
89 monitor = G_FILE_MONITOR (object);
94 g_file_monitor_set_rate_limit (monitor, g_value_get_int (value));
98 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
104 g_file_monitor_get_property (GObject *object,
109 GFileMonitor *monitor;
110 GFileMonitorPrivate *priv;
112 monitor = G_FILE_MONITOR (object);
113 priv = monitor->priv;
117 case PROP_RATE_LIMIT:
118 g_value_set_int (value, priv->rate_limit_msec);
123 g_value_set_boolean (value, priv->cancelled);
124 G_UNLOCK (cancelled);
128 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
133 #define DEFAULT_RATE_LIMIT_MSECS 800
134 #define DEFAULT_VIRTUAL_CHANGES_DONE_DELAY_SECS 2
136 static guint signals[LAST_SIGNAL] = { 0 };
139 rate_limiter_free (RateLimiter *limiter)
141 g_object_unref (limiter->file);
142 g_slice_free (RateLimiter, limiter);
146 g_file_monitor_finalize (GObject *object)
148 GFileMonitor *monitor;
150 monitor = G_FILE_MONITOR (object);
152 if (monitor->priv->timeout)
154 g_source_destroy (monitor->priv->timeout);
155 g_source_unref (monitor->priv->timeout);
158 g_hash_table_destroy (monitor->priv->rate_limiter);
160 if (G_OBJECT_CLASS (g_file_monitor_parent_class)->finalize)
161 (*G_OBJECT_CLASS (g_file_monitor_parent_class)->finalize) (object);
165 g_file_monitor_dispose (GObject *object)
167 GFileMonitor *monitor;
169 monitor = G_FILE_MONITOR (object);
171 /* Make sure we cancel on last unref */
172 g_file_monitor_cancel (monitor);
174 if (G_OBJECT_CLASS (g_file_monitor_parent_class)->dispose)
175 (*G_OBJECT_CLASS (g_file_monitor_parent_class)->dispose) (object);
179 g_file_monitor_class_init (GFileMonitorClass *klass)
181 GObjectClass *object_class;
183 g_type_class_add_private (klass, sizeof (GFileMonitorPrivate));
185 object_class = G_OBJECT_CLASS (klass);
186 object_class->finalize = g_file_monitor_finalize;
187 object_class->dispose = g_file_monitor_dispose;
188 object_class->get_property = g_file_monitor_get_property;
189 object_class->set_property = g_file_monitor_set_property;
192 * GFileMonitor::changed:
193 * @monitor: a #GFileMonitor.
195 * @other_file: a #GFile.
196 * @event_type: a #GFileMonitorEvent.
198 * Emitted when a file has been changed.
201 g_signal_new (I_("changed"),
204 G_STRUCT_OFFSET (GFileMonitorClass, changed),
206 _gio_marshal_VOID__OBJECT_OBJECT_ENUM,
208 G_TYPE_FILE, G_TYPE_FILE, G_TYPE_FILE_MONITOR_EVENT);
210 g_object_class_install_property (object_class,
212 g_param_spec_int ("rate-limit",
214 P_("The limit of the monitor to watch for changes, in milliseconds"),
216 DEFAULT_RATE_LIMIT_MSECS,
218 G_PARAM_STATIC_NAME|G_PARAM_STATIC_NICK|G_PARAM_STATIC_BLURB));
220 g_object_class_install_property (object_class,
222 g_param_spec_boolean ("cancelled",
224 P_("Whether the monitor has been cancelled"),
227 G_PARAM_STATIC_NAME|G_PARAM_STATIC_NICK|G_PARAM_STATIC_BLURB));
231 g_file_monitor_init (GFileMonitor *monitor)
233 monitor->priv = G_TYPE_INSTANCE_GET_PRIVATE (monitor,
235 GFileMonitorPrivate);
236 monitor->priv->rate_limit_msec = DEFAULT_RATE_LIMIT_MSECS;
237 monitor->priv->rate_limiter = g_hash_table_new_full (g_file_hash, (GEqualFunc)g_file_equal,
238 NULL, (GDestroyNotify) rate_limiter_free);
242 * g_file_monitor_is_cancelled:
243 * @monitor: a #GFileMonitor
245 * Returns whether the monitor is canceled.
247 * Returns: %TRUE if monitor is canceled. %FALSE otherwise.
250 g_file_monitor_is_cancelled (GFileMonitor *monitor)
252 g_return_val_if_fail (G_IS_FILE_MONITOR (monitor), FALSE);
256 res = monitor->priv->cancelled;
257 G_UNLOCK (cancelled);
263 * g_file_monitor_cancel:
264 * @monitor: a #GFileMonitor.
266 * Cancels a file monitor.
268 * Returns: %TRUE if monitor was cancelled.
271 g_file_monitor_cancel (GFileMonitor* monitor)
273 GFileMonitorClass *klass;
275 g_return_val_if_fail (G_IS_FILE_MONITOR (monitor), FALSE);
278 if (monitor->priv->cancelled)
280 G_UNLOCK (cancelled);
284 monitor->priv->cancelled = TRUE;
285 G_UNLOCK (cancelled);
287 g_object_notify (G_OBJECT (monitor), "cancelled");
289 klass = G_FILE_MONITOR_GET_CLASS (monitor);
290 return (* klass->cancel) (monitor);
294 * g_file_monitor_set_rate_limit:
295 * @monitor: a #GFileMonitor.
296 * @limit_msecs: a integer with the limit in milliseconds to
299 * Sets the rate limit to which the @monitor will report
300 * consecutive change events to the same file.
304 g_file_monitor_set_rate_limit (GFileMonitor *monitor,
307 GFileMonitorPrivate *priv;
309 g_return_if_fail (G_IS_FILE_MONITOR (monitor));
311 priv = monitor->priv;
312 if (priv->rate_limit_msec != limit_msecs)
314 monitor->priv->rate_limit_msec = limit_msecs;
315 g_object_notify (G_OBJECT (monitor), "rate-limit");
320 GFileMonitor *monitor;
323 GFileMonitorEvent event_type;
327 emit_cb (gpointer data)
329 FileChange *change = data;
330 g_signal_emit (change->monitor, signals[CHANGED], 0,
331 change->child, change->other_file, change->event_type);
336 file_change_free (FileChange *change)
338 g_object_unref (change->monitor);
339 g_object_unref (change->child);
340 if (change->other_file)
341 g_object_unref (change->other_file);
343 g_slice_free (FileChange, change);
347 emit_in_idle (GFileMonitor *monitor,
350 GFileMonitorEvent event_type)
355 change = g_slice_new (FileChange);
357 change->monitor = g_object_ref (monitor);
358 change->child = g_object_ref (child);
360 change->other_file = g_object_ref (other_file);
362 change->other_file = NULL;
363 change->event_type = event_type;
365 source = g_idle_source_new ();
366 g_source_set_priority (source, 0);
368 g_source_set_callback (source, emit_cb, change, (GDestroyNotify)file_change_free);
369 g_source_attach (source, NULL);
370 g_source_unref (source);
374 get_time_msecs (void)
376 return g_thread_gettime() / (1000 * 1000);
380 time_difference (guint32 from, guint32 to)
387 /* Change event rate limiting support: */
390 new_limiter (GFileMonitor *monitor,
393 RateLimiter *limiter;
395 limiter = g_slice_new0 (RateLimiter);
396 limiter->file = g_object_ref (file);
397 g_hash_table_insert (monitor->priv->rate_limiter, file, limiter);
403 rate_limiter_send_virtual_changes_done_now (GFileMonitor *monitor,
404 RateLimiter *limiter)
406 if (limiter->send_virtual_changes_done_at != 0)
408 emit_in_idle (monitor, limiter->file, NULL,
409 G_FILE_MONITOR_EVENT_CHANGES_DONE_HINT);
410 limiter->send_virtual_changes_done_at = 0;
415 rate_limiter_send_delayed_change_now (GFileMonitor *monitor,
416 RateLimiter *limiter,
419 if (limiter->send_delayed_change_at != 0)
421 emit_in_idle (monitor,
423 G_FILE_MONITOR_EVENT_CHANGED);
424 limiter->send_delayed_change_at = 0;
425 limiter->last_sent_change_time = time_now;
432 GFileMonitor *monitor;
436 calc_min_time (GFileMonitor *monitor,
437 RateLimiter *limiter,
446 if (limiter->last_sent_change_time != 0)
448 /* Set a timeout at 2*rate limit so that we can clear out the change from the hash eventualy */
449 expire_at = limiter->last_sent_change_time + 2 * monitor->priv->rate_limit_msec;
451 if (time_difference (time_now, expire_at) > 0)
454 *min_time = MIN (*min_time,
455 time_difference (time_now, expire_at));
459 if (limiter->send_delayed_change_at != 0)
462 *min_time = MIN (*min_time,
463 time_difference (time_now, limiter->send_delayed_change_at));
466 if (limiter->send_virtual_changes_done_at != 0)
469 *min_time = MIN (*min_time,
470 time_difference (time_now, limiter->send_virtual_changes_done_at));
477 foreach_rate_limiter_fire (gpointer key,
481 RateLimiter *limiter = value;
482 ForEachData *data = user_data;
484 if (limiter->send_delayed_change_at != 0 &&
485 time_difference (data->time_now, limiter->send_delayed_change_at) == 0)
486 rate_limiter_send_delayed_change_now (data->monitor, limiter, data->time_now);
488 if (limiter->send_virtual_changes_done_at != 0 &&
489 time_difference (data->time_now, limiter->send_virtual_changes_done_at) == 0)
490 rate_limiter_send_virtual_changes_done_now (data->monitor, limiter);
492 return calc_min_time (data->monitor, limiter, data->time_now, &data->min_time);
496 rate_limiter_timeout (gpointer timeout_data)
498 GFileMonitor *monitor = timeout_data;
502 data.min_time = G_MAXUINT32;
503 data.monitor = monitor;
504 data.time_now = get_time_msecs ();
505 g_hash_table_foreach_remove (monitor->priv->rate_limiter,
506 foreach_rate_limiter_fire,
509 /* Remove old timeout */
510 if (monitor->priv->timeout)
512 g_source_destroy (monitor->priv->timeout);
513 g_source_unref (monitor->priv->timeout);
514 monitor->priv->timeout = NULL;
515 monitor->priv->timeout_fires_at = 0;
518 /* Set up new timeout */
519 if (data.min_time != G_MAXUINT32)
521 source = g_timeout_source_new (data.min_time + 1); /* + 1 to make sure we've really passed the time */
522 g_source_set_callback (source, rate_limiter_timeout, monitor, NULL);
523 g_source_attach (source, NULL);
525 monitor->priv->timeout = source;
526 monitor->priv->timeout_fires_at = data.time_now + data.min_time;
533 foreach_rate_limiter_update (gpointer key,
537 RateLimiter *limiter = value;
538 ForEachData *data = user_data;
540 return calc_min_time (data->monitor, limiter, data->time_now, &data->min_time);
544 update_rate_limiter_timeout (GFileMonitor *monitor,
550 if (monitor->priv->timeout_fires_at != 0 && new_time != 0 &&
551 time_difference (new_time, monitor->priv->timeout_fires_at) == 0)
552 return; /* Nothing to do, we already fire earlier than that */
554 data.min_time = G_MAXUINT32;
555 data.monitor = monitor;
556 data.time_now = get_time_msecs ();
557 g_hash_table_foreach_remove (monitor->priv->rate_limiter,
558 foreach_rate_limiter_update,
561 /* Remove old timeout */
562 if (monitor->priv->timeout)
564 g_source_destroy (monitor->priv->timeout);
565 g_source_unref (monitor->priv->timeout);
566 monitor->priv->timeout_fires_at = 0;
567 monitor->priv->timeout = NULL;
570 /* Set up new timeout */
571 if (data.min_time != G_MAXUINT32)
573 source = g_timeout_source_new (data.min_time + 1); /* + 1 to make sure we've really passed the time */
574 g_source_set_callback (source, rate_limiter_timeout, monitor, NULL);
575 g_source_attach (source, NULL);
577 monitor->priv->timeout = source;
578 monitor->priv->timeout_fires_at = data.time_now + data.min_time;
583 * g_file_monitor_emit_event:
584 * @monitor: a #GFileMonitor.
586 * @other_file: a #GFile.
587 * @event_type: a set of #GFileMonitorEvent flags.
589 * Emits the #GFileMonitor::changed signal if a change
590 * has taken place. Should be called from file monitor
591 * implementations only.
593 * The signal will be emitted from an idle handler.
596 g_file_monitor_emit_event (GFileMonitor *monitor,
599 GFileMonitorEvent event_type)
601 guint32 time_now, since_last;
603 RateLimiter *limiter;
605 g_return_if_fail (G_IS_FILE_MONITOR (monitor));
606 g_return_if_fail (G_IS_FILE (child));
608 limiter = g_hash_table_lookup (monitor->priv->rate_limiter, child);
610 if (event_type != G_FILE_MONITOR_EVENT_CHANGED)
614 rate_limiter_send_delayed_change_now (monitor, limiter, get_time_msecs ());
615 if (event_type == G_FILE_MONITOR_EVENT_CHANGES_DONE_HINT)
616 limiter->send_virtual_changes_done_at = 0;
618 rate_limiter_send_virtual_changes_done_now (monitor, limiter);
619 update_rate_limiter_timeout (monitor, 0);
621 emit_in_idle (monitor, child, other_file, event_type);
625 /* Changed event, rate limit */
626 time_now = get_time_msecs ();
631 since_last = time_difference (limiter->last_sent_change_time, time_now);
632 if (since_last < monitor->priv->rate_limit_msec)
634 /* We ignore this change, but arm a timer so that we can fire it later if we
635 don't get any other events (that kill this timeout) */
637 if (limiter->send_delayed_change_at == 0)
639 limiter->send_delayed_change_at = time_now + monitor->priv->rate_limit_msec;
640 update_rate_limiter_timeout (monitor, limiter->send_delayed_change_at);
646 limiter = new_limiter (monitor, child);
650 emit_in_idle (monitor, child, other_file, event_type);
652 limiter->last_sent_change_time = time_now;
653 limiter->send_delayed_change_at = 0;
654 /* Set a timeout of 2*rate limit so that we can clear out the change from the hash eventualy */
655 update_rate_limiter_timeout (monitor, time_now + 2 * monitor->priv->rate_limit_msec);
658 /* Schedule a virtual change done. This is removed if we get a real one, and
659 postponed if we get more change events. */
661 limiter->send_virtual_changes_done_at = time_now + DEFAULT_VIRTUAL_CHANGES_DONE_DELAY_SECS * 1000;
662 update_rate_limiter_timeout (monitor, limiter->send_virtual_changes_done_at);
666 #define __G_FILE_MONITOR_C__
667 #include "gioaliasdef.c"