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 G_OBJECT_CLASS (g_file_monitor_parent_class)->finalize (object);
164 g_file_monitor_dispose (GObject *object)
166 GFileMonitor *monitor;
168 monitor = G_FILE_MONITOR (object);
170 /* Make sure we cancel on last unref */
171 g_file_monitor_cancel (monitor);
173 G_OBJECT_CLASS (g_file_monitor_parent_class)->dispose (object);
177 g_file_monitor_class_init (GFileMonitorClass *klass)
179 GObjectClass *object_class;
181 g_type_class_add_private (klass, sizeof (GFileMonitorPrivate));
183 object_class = G_OBJECT_CLASS (klass);
184 object_class->finalize = g_file_monitor_finalize;
185 object_class->dispose = g_file_monitor_dispose;
186 object_class->get_property = g_file_monitor_get_property;
187 object_class->set_property = g_file_monitor_set_property;
190 * GFileMonitor::changed:
191 * @monitor: a #GFileMonitor.
193 * @other_file: a #GFile.
194 * @event_type: a #GFileMonitorEvent.
196 * Emitted when a file has been changed.
199 g_signal_new (I_("changed"),
202 G_STRUCT_OFFSET (GFileMonitorClass, changed),
204 _gio_marshal_VOID__OBJECT_OBJECT_ENUM,
206 G_TYPE_FILE, G_TYPE_FILE, G_TYPE_FILE_MONITOR_EVENT);
208 g_object_class_install_property (object_class,
210 g_param_spec_int ("rate-limit",
212 P_("The limit of the monitor to watch for changes, in milliseconds"),
214 DEFAULT_RATE_LIMIT_MSECS,
216 G_PARAM_STATIC_NAME|G_PARAM_STATIC_NICK|G_PARAM_STATIC_BLURB));
218 g_object_class_install_property (object_class,
220 g_param_spec_boolean ("cancelled",
222 P_("Whether the monitor has been cancelled"),
225 G_PARAM_STATIC_NAME|G_PARAM_STATIC_NICK|G_PARAM_STATIC_BLURB));
229 g_file_monitor_init (GFileMonitor *monitor)
231 monitor->priv = G_TYPE_INSTANCE_GET_PRIVATE (monitor,
233 GFileMonitorPrivate);
234 monitor->priv->rate_limit_msec = DEFAULT_RATE_LIMIT_MSECS;
235 monitor->priv->rate_limiter = g_hash_table_new_full (g_file_hash, (GEqualFunc)g_file_equal,
236 NULL, (GDestroyNotify) rate_limiter_free);
240 * g_file_monitor_is_cancelled:
241 * @monitor: a #GFileMonitor
243 * Returns whether the monitor is canceled.
245 * Returns: %TRUE if monitor is canceled. %FALSE otherwise.
248 g_file_monitor_is_cancelled (GFileMonitor *monitor)
252 g_return_val_if_fail (G_IS_FILE_MONITOR (monitor), FALSE);
255 res = monitor->priv->cancelled;
256 G_UNLOCK (cancelled);
262 * g_file_monitor_cancel:
263 * @monitor: a #GFileMonitor.
265 * Cancels a file monitor.
267 * Returns: %TRUE if monitor was cancelled.
270 g_file_monitor_cancel (GFileMonitor* monitor)
272 GFileMonitorClass *klass;
274 g_return_val_if_fail (G_IS_FILE_MONITOR (monitor), FALSE);
277 if (monitor->priv->cancelled)
279 G_UNLOCK (cancelled);
283 monitor->priv->cancelled = TRUE;
284 G_UNLOCK (cancelled);
286 g_object_notify (G_OBJECT (monitor), "cancelled");
288 klass = G_FILE_MONITOR_GET_CLASS (monitor);
289 return (* klass->cancel) (monitor);
293 * g_file_monitor_set_rate_limit:
294 * @monitor: a #GFileMonitor.
295 * @limit_msecs: a integer with the limit in milliseconds to
298 * Sets the rate limit to which the @monitor will report
299 * consecutive change events to the same file.
303 g_file_monitor_set_rate_limit (GFileMonitor *monitor,
306 GFileMonitorPrivate *priv;
308 g_return_if_fail (G_IS_FILE_MONITOR (monitor));
310 priv = monitor->priv;
311 if (priv->rate_limit_msec != limit_msecs)
313 monitor->priv->rate_limit_msec = limit_msecs;
314 g_object_notify (G_OBJECT (monitor), "rate-limit");
319 GFileMonitor *monitor;
322 GFileMonitorEvent event_type;
326 emit_cb (gpointer data)
328 FileChange *change = data;
329 g_signal_emit (change->monitor, signals[CHANGED], 0,
330 change->child, change->other_file, change->event_type);
335 file_change_free (FileChange *change)
337 g_object_unref (change->monitor);
338 g_object_unref (change->child);
339 if (change->other_file)
340 g_object_unref (change->other_file);
342 g_slice_free (FileChange, change);
346 emit_in_idle (GFileMonitor *monitor,
349 GFileMonitorEvent event_type)
354 change = g_slice_new (FileChange);
356 change->monitor = g_object_ref (monitor);
357 change->child = g_object_ref (child);
359 change->other_file = g_object_ref (other_file);
361 change->other_file = NULL;
362 change->event_type = event_type;
364 source = g_idle_source_new ();
365 g_source_set_priority (source, 0);
367 g_source_set_callback (source, emit_cb, change, (GDestroyNotify)file_change_free);
368 g_source_attach (source, NULL);
369 g_source_unref (source);
373 get_time_msecs (void)
375 return g_thread_gettime() / (1000 * 1000);
379 time_difference (guint32 from, guint32 to)
386 /* Change event rate limiting support: */
389 new_limiter (GFileMonitor *monitor,
392 RateLimiter *limiter;
394 limiter = g_slice_new0 (RateLimiter);
395 limiter->file = g_object_ref (file);
396 g_hash_table_insert (monitor->priv->rate_limiter, file, limiter);
402 rate_limiter_send_virtual_changes_done_now (GFileMonitor *monitor,
403 RateLimiter *limiter)
405 if (limiter->send_virtual_changes_done_at != 0)
407 emit_in_idle (monitor, limiter->file, NULL,
408 G_FILE_MONITOR_EVENT_CHANGES_DONE_HINT);
409 limiter->send_virtual_changes_done_at = 0;
414 rate_limiter_send_delayed_change_now (GFileMonitor *monitor,
415 RateLimiter *limiter,
418 if (limiter->send_delayed_change_at != 0)
420 emit_in_idle (monitor,
422 G_FILE_MONITOR_EVENT_CHANGED);
423 limiter->send_delayed_change_at = 0;
424 limiter->last_sent_change_time = time_now;
431 GFileMonitor *monitor;
435 calc_min_time (GFileMonitor *monitor,
436 RateLimiter *limiter,
445 if (limiter->last_sent_change_time != 0)
447 /* Set a timeout at 2*rate limit so that we can clear out the change from the hash eventualy */
448 expire_at = limiter->last_sent_change_time + 2 * monitor->priv->rate_limit_msec;
450 if (time_difference (time_now, expire_at) > 0)
453 *min_time = MIN (*min_time,
454 time_difference (time_now, expire_at));
458 if (limiter->send_delayed_change_at != 0)
461 *min_time = MIN (*min_time,
462 time_difference (time_now, limiter->send_delayed_change_at));
465 if (limiter->send_virtual_changes_done_at != 0)
468 *min_time = MIN (*min_time,
469 time_difference (time_now, limiter->send_virtual_changes_done_at));
476 foreach_rate_limiter_fire (gpointer key,
480 RateLimiter *limiter = value;
481 ForEachData *data = user_data;
483 if (limiter->send_delayed_change_at != 0 &&
484 time_difference (data->time_now, limiter->send_delayed_change_at) == 0)
485 rate_limiter_send_delayed_change_now (data->monitor, limiter, data->time_now);
487 if (limiter->send_virtual_changes_done_at != 0 &&
488 time_difference (data->time_now, limiter->send_virtual_changes_done_at) == 0)
489 rate_limiter_send_virtual_changes_done_now (data->monitor, limiter);
491 return calc_min_time (data->monitor, limiter, data->time_now, &data->min_time);
495 rate_limiter_timeout (gpointer timeout_data)
497 GFileMonitor *monitor = timeout_data;
501 data.min_time = G_MAXUINT32;
502 data.monitor = monitor;
503 data.time_now = get_time_msecs ();
504 g_hash_table_foreach_remove (monitor->priv->rate_limiter,
505 foreach_rate_limiter_fire,
508 /* Remove old timeout */
509 if (monitor->priv->timeout)
511 g_source_destroy (monitor->priv->timeout);
512 g_source_unref (monitor->priv->timeout);
513 monitor->priv->timeout = NULL;
514 monitor->priv->timeout_fires_at = 0;
517 /* Set up new timeout */
518 if (data.min_time != G_MAXUINT32)
520 source = g_timeout_source_new (data.min_time + 1); /* + 1 to make sure we've really passed the time */
521 g_source_set_callback (source, rate_limiter_timeout, monitor, NULL);
522 g_source_attach (source, NULL);
524 monitor->priv->timeout = source;
525 monitor->priv->timeout_fires_at = data.time_now + data.min_time;
532 foreach_rate_limiter_update (gpointer key,
536 RateLimiter *limiter = value;
537 ForEachData *data = user_data;
539 return calc_min_time (data->monitor, limiter, data->time_now, &data->min_time);
543 update_rate_limiter_timeout (GFileMonitor *monitor,
549 if (monitor->priv->timeout_fires_at != 0 && new_time != 0 &&
550 time_difference (new_time, monitor->priv->timeout_fires_at) == 0)
551 return; /* Nothing to do, we already fire earlier than that */
553 data.min_time = G_MAXUINT32;
554 data.monitor = monitor;
555 data.time_now = get_time_msecs ();
556 g_hash_table_foreach_remove (monitor->priv->rate_limiter,
557 foreach_rate_limiter_update,
560 /* Remove old timeout */
561 if (monitor->priv->timeout)
563 g_source_destroy (monitor->priv->timeout);
564 g_source_unref (monitor->priv->timeout);
565 monitor->priv->timeout_fires_at = 0;
566 monitor->priv->timeout = NULL;
569 /* Set up new timeout */
570 if (data.min_time != G_MAXUINT32)
572 source = g_timeout_source_new (data.min_time + 1); /* + 1 to make sure we've really passed the time */
573 g_source_set_callback (source, rate_limiter_timeout, monitor, NULL);
574 g_source_attach (source, NULL);
576 monitor->priv->timeout = source;
577 monitor->priv->timeout_fires_at = data.time_now + data.min_time;
582 * g_file_monitor_emit_event:
583 * @monitor: a #GFileMonitor.
585 * @other_file: a #GFile.
586 * @event_type: a set of #GFileMonitorEvent flags.
588 * Emits the #GFileMonitor::changed signal if a change
589 * has taken place. Should be called from file monitor
590 * implementations only.
592 * The signal will be emitted from an idle handler.
595 g_file_monitor_emit_event (GFileMonitor *monitor,
598 GFileMonitorEvent event_type)
600 guint32 time_now, since_last;
602 RateLimiter *limiter;
604 g_return_if_fail (G_IS_FILE_MONITOR (monitor));
605 g_return_if_fail (G_IS_FILE (child));
607 limiter = g_hash_table_lookup (monitor->priv->rate_limiter, child);
609 if (event_type != G_FILE_MONITOR_EVENT_CHANGED)
613 rate_limiter_send_delayed_change_now (monitor, limiter, get_time_msecs ());
614 if (event_type == G_FILE_MONITOR_EVENT_CHANGES_DONE_HINT)
615 limiter->send_virtual_changes_done_at = 0;
617 rate_limiter_send_virtual_changes_done_now (monitor, limiter);
618 update_rate_limiter_timeout (monitor, 0);
620 emit_in_idle (monitor, child, other_file, event_type);
624 /* Changed event, rate limit */
625 time_now = get_time_msecs ();
630 since_last = time_difference (limiter->last_sent_change_time, time_now);
631 if (since_last < monitor->priv->rate_limit_msec)
633 /* We ignore this change, but arm a timer so that we can fire it later if we
634 don't get any other events (that kill this timeout) */
636 if (limiter->send_delayed_change_at == 0)
638 limiter->send_delayed_change_at = time_now + monitor->priv->rate_limit_msec;
639 update_rate_limiter_timeout (monitor, limiter->send_delayed_change_at);
645 limiter = new_limiter (monitor, child);
649 emit_in_idle (monitor, child, other_file, event_type);
651 limiter->last_sent_change_time = time_now;
652 limiter->send_delayed_change_at = 0;
653 /* Set a timeout of 2*rate limit so that we can clear out the change from the hash eventualy */
654 update_rate_limiter_timeout (monitor, time_now + 2 * monitor->priv->rate_limit_msec);
657 /* Schedule a virtual change done. This is removed if we get a real one, and
658 postponed if we get more change events. */
660 limiter->send_virtual_changes_done_at = time_now + DEFAULT_VIRTUAL_CHANGES_DONE_DELAY_SECS * 1000;
661 update_rate_limiter_timeout (monitor, limiter->send_virtual_changes_done_at);
665 #define __G_FILE_MONITOR_C__
666 #include "gioaliasdef.c"