[mutter] idle-monitor-native: Don't leak user active watches

[Ray Strode <halfline src gnome org>]

commit 5e57af62866b4d24c68b72b3467797e72de391bd
Author: Rui Matos <tiagomatos gmail com>
Date:   Mon Jan 11 17:04:11 2016 +0100

    idle-monitor-native: Don't leak user active watches
    
    This fixes an issue analogous to bug 760330 for the X11 backend,
    except on this backend we wouldn't crash accessing free'd memory.
    
    Instead we're leaking watches since we steal them from the hash table
    which means that when they're removed in
    _meta_idle_monitor_watch_fire() they're no longer there and thus
    they're never free'd.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=760476

 src/backends/native/meta-idle-monitor-native.c |   68 ++++++++---------------
 1 files changed, 24 insertions(+), 44 deletions(-)
---
diff --git a/src/backends/native/meta-idle-monitor-native.c b/src/backends/native/meta-idle-monitor-native.c
index 13d8d51..da1ad06 100644
--- a/src/backends/native/meta-idle-monitor-native.c
+++ b/src/backends/native/meta-idle-monitor-native.c
@@ -164,56 +164,36 @@ meta_idle_monitor_native_init (MetaIdleMonitorNative *monitor_native)
   monitor->watches = g_hash_table_new_full (NULL, NULL, NULL, free_watch);
 }
 
-typedef struct {
-  MetaIdleMonitorNative *monitor_native;
-  GList *fired_watches;
-} CheckNativeClosure;
-
-static gboolean
-check_native_watch (gpointer key,
-                    gpointer value,
-                    gpointer user_data)
-{
-  MetaIdleMonitorWatchNative *watch_native = value;
-  MetaIdleMonitorWatch *watch = (MetaIdleMonitorWatch *) watch_native;
-  CheckNativeClosure *closure = user_data;
-  gboolean steal;
-
-  if (watch->timeout_msec == 0)
-    {
-      closure->fired_watches = g_list_prepend (closure->fired_watches, watch);
-      steal = TRUE;
-    }
-  else
-    {
-      g_source_set_ready_time (watch_native->timeout_source,
-                               closure->monitor_native->last_event_time +
-                               watch->timeout_msec * 1000);
-      steal = FALSE;
-    }
-
-  return steal;
-}
-
-static void
-fire_native_watch (gpointer watch,
-                   gpointer data)
-{
-  _meta_idle_monitor_watch_fire (watch);
-}
-
 void
 meta_idle_monitor_native_reset_idletime (MetaIdleMonitor *monitor)
 {
   MetaIdleMonitorNative *monitor_native = META_IDLE_MONITOR_NATIVE (monitor);
-  CheckNativeClosure closure;
+  GList *node, *watch_ids;
 
   monitor_native->last_event_time = g_get_monotonic_time ();
 
-  closure.monitor_native = monitor_native;
-  closure.fired_watches = NULL;
-  g_hash_table_foreach_steal (monitor->watches, check_native_watch, &closure);
+  watch_ids = g_hash_table_get_keys (monitor->watches);
+
+  for (node = watch_ids; node != NULL; node = node->next)
+    {
+      guint watch_id = GPOINTER_TO_UINT (node->data);
+      MetaIdleMonitorWatchNative *watch;
+
+      watch = g_hash_table_lookup (monitor->watches, GUINT_TO_POINTER (watch_id));
+      if (!watch)
+        continue;
+
+      if (watch->base.timeout_msec == 0)
+        {
+          _meta_idle_monitor_watch_fire ((MetaIdleMonitorWatch *) watch);
+        }
+      else
+        {
+          g_source_set_ready_time (watch->timeout_source,
+                                   monitor_native->last_event_time +
+                                   watch->base.timeout_msec * 1000);
+        }
+    }
 
-  g_list_foreach (closure.fired_watches, fire_native_watch, NULL);
-  g_list_free (closure.fired_watches);
+  g_list_free (watch_ids);
 }