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.
53 G_DEFINE_ABSTRACT_TYPE (GFileMonitor, g_file_monitor, G_TYPE_OBJECT);
57 guint32 last_sent_change_time; /* 0 == not sent */
58 guint32 send_delayed_change_at; /* 0 == never */
59 guint32 send_virtual_changes_done_at; /* 0 == never */
62 struct _GFileMonitorPrivate {
66 /* Rate limiting change events */
67 GHashTable *rate_limiter;
70 guint32 timeout_fires_at;
80 g_file_monitor_set_property (GObject *object,
85 GFileMonitor *monitor;
87 monitor = G_FILE_MONITOR (object);
92 g_file_monitor_set_rate_limit (monitor, g_value_get_int (value));
96 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
102 g_file_monitor_get_property (GObject *object,
107 GFileMonitor *monitor;
108 GFileMonitorPrivate *priv;
110 monitor = G_FILE_MONITOR (object);
111 priv = monitor->priv;
115 case PROP_RATE_LIMIT:
116 g_value_set_int (value, priv->rate_limit_msec);
120 g_value_set_boolean (value, priv->cancelled);
124 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
129 #define DEFAULT_RATE_LIMIT_MSECS 800
130 #define DEFAULT_VIRTUAL_CHANGES_DONE_DELAY_SECS 2
132 static guint signals[LAST_SIGNAL] = { 0 };
135 rate_limiter_free (RateLimiter *limiter)
137 g_object_unref (limiter->file);
138 g_slice_free (RateLimiter, limiter);
142 g_file_monitor_finalize (GObject *object)
144 GFileMonitor *monitor;
146 monitor = G_FILE_MONITOR (object);
148 if (monitor->priv->timeout)
150 g_source_destroy (monitor->priv->timeout);
151 g_source_unref (monitor->priv->timeout);
154 g_hash_table_destroy (monitor->priv->rate_limiter);
156 if (G_OBJECT_CLASS (g_file_monitor_parent_class)->finalize)
157 (*G_OBJECT_CLASS (g_file_monitor_parent_class)->finalize) (object);
161 g_file_monitor_dispose (GObject *object)
163 GFileMonitor *monitor;
165 monitor = G_FILE_MONITOR (object);
167 /* Make sure we cancel on last unref */
168 if (!monitor->priv->cancelled)
169 g_file_monitor_cancel (monitor);
171 if (G_OBJECT_CLASS (g_file_monitor_parent_class)->dispose)
172 (*G_OBJECT_CLASS (g_file_monitor_parent_class)->dispose) (object);
176 g_file_monitor_class_init (GFileMonitorClass *klass)
178 GObjectClass *object_class;
180 g_type_class_add_private (klass, sizeof (GFileMonitorPrivate));
182 object_class = G_OBJECT_CLASS (klass);
183 object_class->finalize = g_file_monitor_finalize;
184 object_class->dispose = g_file_monitor_dispose;
185 object_class->get_property = g_file_monitor_get_property;
186 object_class->set_property = g_file_monitor_set_property;
189 * GFileMonitor::changed:
190 * @monitor: a #GFileMonitor.
192 * @other_file: a #GFile.
193 * @event_type: a #GFileMonitorEvent.
195 * Emitted when a file has been changed.
198 g_signal_new (I_("changed"),
201 G_STRUCT_OFFSET (GFileMonitorClass, changed),
203 _gio_marshal_VOID__OBJECT_OBJECT_ENUM,
205 G_TYPE_FILE, G_TYPE_FILE, G_TYPE_FILE_MONITOR_EVENT);
207 g_object_class_install_property (object_class,
209 g_param_spec_int ("rate-limit",
211 P_("The limit of the monitor to watch for changes, in milliseconds"),
213 DEFAULT_RATE_LIMIT_MSECS,
215 G_PARAM_STATIC_NAME|G_PARAM_STATIC_NICK|G_PARAM_STATIC_BLURB));
217 g_object_class_install_property (object_class,
219 g_param_spec_boolean ("cancelled",
221 P_("Whether the monitor has been cancelled"),
224 G_PARAM_STATIC_NAME|G_PARAM_STATIC_NICK|G_PARAM_STATIC_BLURB));
228 g_file_monitor_init (GFileMonitor *monitor)
230 monitor->priv = G_TYPE_INSTANCE_GET_PRIVATE (monitor,
232 GFileMonitorPrivate);
233 monitor->priv->rate_limit_msec = DEFAULT_RATE_LIMIT_MSECS;
234 monitor->priv->rate_limiter = g_hash_table_new_full (g_file_hash, (GEqualFunc)g_file_equal,
235 NULL, (GDestroyNotify) rate_limiter_free);
239 * g_file_monitor_is_cancelled:
240 * @monitor: a #GFileMonitor
242 * Returns whether the monitor is canceled.
244 * Returns: %TRUE if monitor is canceled. %FALSE otherwise.
247 g_file_monitor_is_cancelled (GFileMonitor *monitor)
249 g_return_val_if_fail (G_IS_FILE_MONITOR (monitor), FALSE);
251 return monitor->priv->cancelled;
255 * g_file_monitor_cancel:
256 * @monitor: a #GFileMonitor.
258 * Cancels a file monitor.
260 * Returns: %TRUE if monitor was cancelled.
263 g_file_monitor_cancel (GFileMonitor* monitor)
265 GFileMonitorClass *klass;
267 g_return_val_if_fail (G_IS_FILE_MONITOR (monitor), FALSE);
269 if (monitor->priv->cancelled)
272 monitor->priv->cancelled = TRUE;
273 g_object_notify (G_OBJECT (monitor), "cancelled");
275 klass = G_FILE_MONITOR_GET_CLASS (monitor);
276 return (* klass->cancel) (monitor);
280 * g_file_monitor_set_rate_limit:
281 * @monitor: a #GFileMonitor.
282 * @limit_msecs: a integer with the limit in milliseconds to
285 * Sets the rate limit to which the @monitor will report
286 * consecutive change events to the same file.
290 g_file_monitor_set_rate_limit (GFileMonitor *monitor,
293 GFileMonitorPrivate *priv;
295 g_return_if_fail (G_IS_FILE_MONITOR (monitor));
297 priv = monitor->priv;
298 if (priv->rate_limit_msec != limit_msecs)
300 monitor->priv->rate_limit_msec = limit_msecs;
301 g_object_notify (G_OBJECT (monitor), "rate-limit");
306 GFileMonitor *monitor;
309 GFileMonitorEvent event_type;
313 emit_cb (gpointer data)
315 FileChange *change = data;
316 g_signal_emit (change->monitor, signals[CHANGED], 0,
317 change->child, change->other_file, change->event_type);
322 file_change_free (FileChange *change)
324 g_object_unref (change->monitor);
325 g_object_unref (change->child);
326 if (change->other_file)
327 g_object_unref (change->other_file);
329 g_slice_free (FileChange, change);
333 emit_in_idle (GFileMonitor *monitor,
336 GFileMonitorEvent event_type)
341 change = g_slice_new (FileChange);
343 change->monitor = g_object_ref (monitor);
344 change->child = g_object_ref (child);
346 change->other_file = g_object_ref (other_file);
348 change->other_file = NULL;
349 change->event_type = event_type;
351 source = g_idle_source_new ();
352 g_source_set_priority (source, 0);
354 g_source_set_callback (source, emit_cb, change, file_change_free);
355 g_source_attach (source, NULL);
356 g_source_unref (source);
360 get_time_msecs (void)
362 return g_thread_gettime() / (1000 * 1000);
366 time_difference (guint32 from, guint32 to)
373 /* Change event rate limiting support: */
376 new_limiter (GFileMonitor *monitor,
379 RateLimiter *limiter;
381 limiter = g_slice_new0 (RateLimiter);
382 limiter->file = g_object_ref (file);
383 g_hash_table_insert (monitor->priv->rate_limiter, file, limiter);
389 rate_limiter_send_virtual_changes_done_now (GFileMonitor *monitor,
390 RateLimiter *limiter)
392 if (limiter->send_virtual_changes_done_at != 0)
394 emit_in_idle (monitor, limiter->file, NULL,
395 G_FILE_MONITOR_EVENT_CHANGES_DONE_HINT);
396 limiter->send_virtual_changes_done_at = 0;
401 rate_limiter_send_delayed_change_now (GFileMonitor *monitor,
402 RateLimiter *limiter,
405 if (limiter->send_delayed_change_at != 0)
407 emit_in_idle (monitor,
409 G_FILE_MONITOR_EVENT_CHANGED);
410 limiter->send_delayed_change_at = 0;
411 limiter->last_sent_change_time = time_now;
418 GFileMonitor *monitor;
422 calc_min_time (GFileMonitor *monitor,
423 RateLimiter *limiter,
432 if (limiter->last_sent_change_time != 0)
434 /* Set a timeout at 2*rate limit so that we can clear out the change from the hash eventualy */
435 expire_at = limiter->last_sent_change_time + 2 * monitor->priv->rate_limit_msec;
437 if (time_difference (time_now, expire_at) > 0)
440 *min_time = MIN (*min_time,
441 time_difference (time_now, expire_at));
445 if (limiter->send_delayed_change_at != 0)
448 *min_time = MIN (*min_time,
449 time_difference (time_now, limiter->send_delayed_change_at));
452 if (limiter->send_virtual_changes_done_at != 0)
455 *min_time = MIN (*min_time,
456 time_difference (time_now, limiter->send_virtual_changes_done_at));
463 foreach_rate_limiter_fire (gpointer key,
467 RateLimiter *limiter = value;
468 ForEachData *data = user_data;
470 if (limiter->send_delayed_change_at != 0 &&
471 time_difference (data->time_now, limiter->send_delayed_change_at) == 0)
472 rate_limiter_send_delayed_change_now (data->monitor, limiter, data->time_now);
474 if (limiter->send_virtual_changes_done_at != 0 &&
475 time_difference (data->time_now, limiter->send_virtual_changes_done_at) == 0)
476 rate_limiter_send_virtual_changes_done_now (data->monitor, limiter);
478 return calc_min_time (data->monitor, limiter, data->time_now, &data->min_time);
482 rate_limiter_timeout (gpointer timeout_data)
484 GFileMonitor *monitor = timeout_data;
488 data.min_time = G_MAXUINT32;
489 data.monitor = monitor;
490 data.time_now = get_time_msecs ();
491 g_hash_table_foreach_remove (monitor->priv->rate_limiter,
492 foreach_rate_limiter_fire,
495 /* Remove old timeout */
496 if (monitor->priv->timeout)
498 g_source_destroy (monitor->priv->timeout);
499 g_source_unref (monitor->priv->timeout);
500 monitor->priv->timeout = NULL;
501 monitor->priv->timeout_fires_at = 0;
504 /* Set up new timeout */
505 if (data.min_time != G_MAXUINT32)
507 source = g_timeout_source_new (data.min_time + 1); /* + 1 to make sure we've really passed the time */
508 g_source_set_callback (source, rate_limiter_timeout, monitor, NULL);
509 g_source_attach (source, NULL);
511 monitor->priv->timeout = source;
512 monitor->priv->timeout_fires_at = data.time_now + data.min_time;
519 foreach_rate_limiter_update (gpointer key,
523 RateLimiter *limiter = value;
524 ForEachData *data = user_data;
526 return calc_min_time (data->monitor, limiter, data->time_now, &data->min_time);
530 update_rate_limiter_timeout (GFileMonitor *monitor,
536 if (monitor->priv->timeout_fires_at != 0 && new_time != 0 &&
537 time_difference (new_time, monitor->priv->timeout_fires_at) == 0)
538 return; /* Nothing to do, we already fire earlier than that */
540 data.min_time = G_MAXUINT32;
541 data.monitor = monitor;
542 data.time_now = get_time_msecs ();
543 g_hash_table_foreach_remove (monitor->priv->rate_limiter,
544 foreach_rate_limiter_update,
547 /* Remove old timeout */
548 if (monitor->priv->timeout)
550 g_source_destroy (monitor->priv->timeout);
551 g_source_unref (monitor->priv->timeout);
552 monitor->priv->timeout_fires_at = 0;
553 monitor->priv->timeout = NULL;
556 /* Set up new timeout */
557 if (data.min_time != G_MAXUINT32)
559 source = g_timeout_source_new (data.min_time + 1); /* + 1 to make sure we've really passed the time */
560 g_source_set_callback (source, rate_limiter_timeout, monitor, NULL);
561 g_source_attach (source, NULL);
563 monitor->priv->timeout = source;
564 monitor->priv->timeout_fires_at = data.time_now + data.min_time;
569 * g_file_monitor_emit_event:
570 * @monitor: a #GFileMonitor.
572 * @other_file: a #GFile.
573 * @event_type: a set of #GFileMonitorEvent flags.
575 * Emits the #GFileMonitor::changed signal if a change
576 * has taken place. Should be called from file monitor
577 * implementations only.
579 * The signal will be emitted from an idle handler.
582 g_file_monitor_emit_event (GFileMonitor *monitor,
585 GFileMonitorEvent event_type)
587 guint32 time_now, since_last;
589 RateLimiter *limiter;
591 g_return_if_fail (G_IS_FILE_MONITOR (monitor));
592 g_return_if_fail (G_IS_FILE (child));
594 limiter = g_hash_table_lookup (monitor->priv->rate_limiter, child);
596 if (event_type != G_FILE_MONITOR_EVENT_CHANGED)
600 rate_limiter_send_delayed_change_now (monitor, limiter, get_time_msecs ());
601 if (event_type == G_FILE_MONITOR_EVENT_CHANGES_DONE_HINT)
602 limiter->send_virtual_changes_done_at = 0;
604 rate_limiter_send_virtual_changes_done_now (monitor, limiter);
605 update_rate_limiter_timeout (monitor, 0);
607 emit_in_idle (monitor, child, other_file, event_type);
611 /* Changed event, rate limit */
612 time_now = get_time_msecs ();
617 since_last = time_difference (limiter->last_sent_change_time, time_now);
618 if (since_last < monitor->priv->rate_limit_msec)
620 /* We ignore this change, but arm a timer so that we can fire it later if we
621 don't get any other events (that kill this timeout) */
623 if (limiter->send_delayed_change_at == 0)
625 limiter->send_delayed_change_at = time_now + monitor->priv->rate_limit_msec;
626 update_rate_limiter_timeout (monitor, limiter->send_delayed_change_at);
632 limiter = new_limiter (monitor, child);
636 emit_in_idle (monitor, child, other_file, event_type);
638 limiter->last_sent_change_time = time_now;
639 limiter->send_delayed_change_at = 0;
640 /* Set a timeout of 2*rate limit so that we can clear out the change from the hash eventualy */
641 update_rate_limiter_timeout (monitor, time_now + 2 * monitor->priv->rate_limit_msec);
644 /* Schedule a virtual change done. This is removed if we get a real one, and
645 postponed if we get more change events. */
647 limiter->send_virtual_changes_done_at = time_now + DEFAULT_VIRTUAL_CHANGES_DONE_DELAY_SECS * 1000;
648 update_rate_limiter_timeout (monitor, limiter->send_virtual_changes_done_at);
652 #define __G_FILE_MONITOR_C__
653 #include "gioaliasdef.c"