[glib] gmain: block child sources when blocking the parent

[Dan Winship <danw src gnome org>]

commit a49568ceccb133c5a99524f3fdb842f0c05eb0b3
Author: Dan Winship <danw gnome org>
Date:   Wed Apr 11 15:21:17 2012 -0400

    gmain: block child sources when blocking the parent
    
    When blocking a source that has child sources, we need to consider the
    children blocked as well. Otherwise they will still trigger repeatedly
    in an inner loop started from the parent source's callback.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=669260

 glib/gmain.c |   35 +++++++++++++++++++++++++++++------
 1 files changed, 29 insertions(+), 6 deletions(-)
---
diff --git a/glib/gmain.c b/glib/gmain.c
index 68839b5..760f179 100644
--- a/glib/gmain.c
+++ b/glib/gmain.c
@@ -191,7 +191,8 @@ typedef struct _GSourceCallback GSourceCallback;
 typedef enum
 {
   G_SOURCE_READY = 1 << G_HOOK_FLAG_USER_SHIFT,
-  G_SOURCE_CAN_RECURSE = 1 << (G_HOOK_FLAG_USER_SHIFT + 1)
+  G_SOURCE_CAN_RECURSE = 1 << (G_HOOK_FLAG_USER_SHIFT + 1),
+  G_SOURCE_BLOCKED = 1 << (G_HOOK_FLAG_USER_SHIFT + 2)
 } GSourceFlags;
 
 typedef struct _GMainWaiter GMainWaiter;
@@ -313,8 +314,7 @@ struct _GSourcePrivate
 #define G_THREAD_SELF g_thread_self ()
 
 #define SOURCE_DESTROYED(source) (((source)->flags & G_HOOK_FLAG_ACTIVE) == 0)
-#define SOURCE_BLOCKED(source) (((source)->flags & G_HOOK_FLAG_IN_CALL) != 0 && \
-		                ((source)->flags & G_SOURCE_CAN_RECURSE) == 0)
+#define SOURCE_BLOCKED(source) (((source)->flags & G_SOURCE_BLOCKED) != 0)
 
 #define SOURCE_UNREF(source, context)                       \
    G_STMT_START {                                           \
@@ -2426,12 +2426,24 @@ block_source (GSource *source)
 
   g_return_if_fail (!SOURCE_BLOCKED (source));
 
+  source->flags |= G_SOURCE_BLOCKED;
+
   tmp_list = source->poll_fds;
   while (tmp_list)
     {
       g_main_context_remove_poll_unlocked (source->context, tmp_list->data);
       tmp_list = tmp_list->next;
     }
+
+  if (source->priv && source->priv->child_sources)
+    {
+      tmp_list = source->priv->child_sources;
+      while (tmp_list)
+	{
+	  block_source (tmp_list->data);
+	  tmp_list = tmp_list->next;
+	}
+    }
 }
 
 /* HOLDS: source->context's lock */
@@ -2440,15 +2452,27 @@ unblock_source (GSource *source)
 {
   GSList *tmp_list;
   
-  g_return_if_fail (!SOURCE_BLOCKED (source)); /* Source already unblocked */
+  g_return_if_fail (SOURCE_BLOCKED (source)); /* Source already unblocked */
   g_return_if_fail (!SOURCE_DESTROYED (source));
   
+  source->flags &= ~G_SOURCE_BLOCKED;
+
   tmp_list = source->poll_fds;
   while (tmp_list)
     {
       g_main_context_add_poll_unlocked (source->context, source->priority, tmp_list->data);
       tmp_list = tmp_list->next;
     }
+
+  if (source->priv && source->priv->child_sources)
+    {
+      tmp_list = source->priv->child_sources;
+      while (tmp_list)
+	{
+	  unblock_source (tmp_list->data);
+	  tmp_list = tmp_list->next;
+	}
+    }
 }
 
 /* HOLDS: context's lock */
@@ -2527,8 +2551,7 @@ g_main_dispatch (GMainContext *context)
 	  if (!was_in_call)
 	    source->flags &= ~G_HOOK_FLAG_IN_CALL;
 
-	  if ((source->flags & G_SOURCE_CAN_RECURSE) == 0 &&
-	      !SOURCE_DESTROYED (source))
+	  if (SOURCE_BLOCKED (source) && !SOURCE_DESTROYED (source))
 	    unblock_source (source);
 	  
 	  /* Note: this depends on the fact that we can't switch