Emit actual change signals in an idle handler. This avoids reentrance and

2008-02-25  Alexander Larsson  <alexl@redhat.com>

        * gfilemonitor.c:
	Emit actual change signals in an idle handler.
	This avoids reentrance and locking problems in
	the file notification backends.

svn path=/trunk/; revision=6584

diff --git a/gio/ChangeLog b/gio/ChangeLog
index 9e4557d..2bbdd21 100644 (file)
--- a/gio/ChangeLog
+++ b/gio/ChangeLog
@@ -1,5 +1,12 @@
 2008-02-25  Alexander Larsson  <alexl@redhat.com>
 
+        * gfilemonitor.c:
+       Emit actual change signals in an idle handler.
+       This avoids reentrance and locking problems in
+       the file notification backends.
+       
+2008-02-25  Alexander Larsson  <alexl@redhat.com>
+
         * gunixmounts.c:
         (g_unix_mount_guess_should_display):
        Remove type guessing, instead just display

diff --git a/gio/gfilemonitor.c b/gio/gfilemonitor.c
index be03d03..105f1a8 100644 (file)
--- a/gio/gfilemonitor.c
+++ b/gio/gfilemonitor.c
@@ -302,6 +302,60 @@ g_file_monitor_set_rate_limit (GFileMonitor *monitor,
     }
 }
 
+typedef struct {
+  GFileMonitor      *monitor;
+  GFile             *child;
+  GFile             *other_file;
+  GFileMonitorEvent  event_type;
+} FileChange;
+
+static gboolean
+emit_cb (gpointer data)
+{
+  FileChange *change = data;
+  g_signal_emit (change->monitor, signals[CHANGED], 0,
+                change->child, change->other_file, change->event_type);
+  return FALSE;
+}
+
+static void
+file_change_free (FileChange *change)
+{
+  g_object_unref (change->monitor);
+  g_object_unref (change->child);
+  if (change->other_file)
+    g_object_unref (change->other_file);
+  
+  g_slice_free (FileChange, change);
+}
+
+static void
+emit_in_idle (GFileMonitor      *monitor,
+             GFile             *child,
+             GFile             *other_file,
+             GFileMonitorEvent  event_type)
+{
+  GSource *source;
+  FileChange *change;
+
+  change = g_slice_new (FileChange);
+
+  change->monitor = g_object_ref (monitor);
+  change->child = g_object_ref (child);
+  if (other_file)
+    change->other_file = g_object_ref (other_file);
+  else
+    change->other_file = NULL;
+  change->event_type = event_type;
+
+  source = g_idle_source_new ();
+  g_source_set_priority (source, 0);
+
+  g_source_set_callback (source, emit_cb, change, file_change_free);
+  g_source_attach (source, NULL);
+  g_source_unref (source);
+}
+
 static guint32
 get_time_msecs (void)
 {
@@ -337,9 +391,8 @@ rate_limiter_send_virtual_changes_done_now (GFileMonitor *monitor,
 {
   if (limiter->send_virtual_changes_done_at != 0)
     {
-      g_signal_emit (monitor, signals[CHANGED], 0,
-                    limiter->file, NULL,
-                    G_FILE_MONITOR_EVENT_CHANGES_DONE_HINT);
+      emit_in_idle (monitor, limiter->file, NULL,
+                   G_FILE_MONITOR_EVENT_CHANGES_DONE_HINT);
       limiter->send_virtual_changes_done_at = 0;
     }
 }
@@ -351,9 +404,9 @@ rate_limiter_send_delayed_change_now (GFileMonitor *monitor,
 {
   if (limiter->send_delayed_change_at != 0)
     {
-      g_signal_emit (monitor, signals[CHANGED], 0,
-                    limiter->file, NULL,
-                    G_FILE_MONITOR_EVENT_CHANGED);
+      emit_in_idle (monitor, 
+                   limiter->file, NULL,
+                   G_FILE_MONITOR_EVENT_CHANGED);
       limiter->send_delayed_change_at = 0;
       limiter->last_sent_change_time = time_now;
     }
@@ -522,6 +575,8 @@ update_rate_limiter_timeout (GFileMonitor *monitor,
  * Emits the #GFileMonitor::changed signal if a change
  * has taken place. Should be called from file monitor 
  * implementations only.
+ *
+ * The signal will be emitted from an idle handler.
  **/
 void
 g_file_monitor_emit_event (GFileMonitor      *monitor,
@@ -549,7 +604,7 @@ g_file_monitor_emit_event (GFileMonitor      *monitor,
            rate_limiter_send_virtual_changes_done_now (monitor, limiter);
          update_rate_limiter_timeout (monitor, 0);
        }
-      g_signal_emit (monitor, signals[CHANGED], 0, child, other_file, event_type);
+      emit_in_idle (monitor, child, other_file, event_type);
     }
   else
     {
@@ -578,7 +633,7 @@ g_file_monitor_emit_event (GFileMonitor      *monitor,
       
       if (emit_now)
        {
-         g_signal_emit (monitor, signals[CHANGED], 0, child, other_file, event_type);
+         emit_in_idle (monitor, child, other_file, event_type);
          
          limiter->last_sent_change_time = time_now;
          limiter->send_delayed_change_at = 0;