When dispatching a source that is !CAN_RECURSE, temporarily remove any

Thu Jun  5 23:40:31 2003  Owen Taylor  <otaylor@redhat.com>

        * glib/gmain.c: When dispatching a source that is
        !CAN_RECURSE, temporarily remove any file descriptors
        that that source has registered from the main loop, to keep
        recursive main loops from busy-waiting if input
        becomes available on one of those file descriptors.
        (#112222, Christian Krause)

        * glib/gmain.c (g_source_set_priority): Properly
        remove the source from the context's source list
        and reinsert it sorted, rather than simply setting
        source->next/prev to NULL! (#114274)

7 files changed, 160 insertions, 19 deletions

diff --git a/ChangeLog b/ChangeLog
index b6d1fe849..7fb979051 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,17 @@
+Thu Jun  5 23:40:31 2003  Owen Taylor  <otaylor@redhat.com>
+
+	* glib/gmain.c: When dispatching a source that is
+	!CAN_RECURSE, temporarily remove any file descriptors
+	that that source has registered from the main loop, to keep
+	recursive main loops from busy-waiting if input
+	becomes available on one of those file descriptors.
+	(#112222, Christian Krause)
+
+	* glib/gmain.c (g_source_set_priority): Properly
+	remove the source from the context's source list
+	and reinsert it sorted, rather than simply setting
+	source->next/prev to NULL! (#114274)
+
 2003-06-06  Matthias Clasen  <maclas@gmx.de>
 
 	* glib/gstring.c (g_string_append_printf_internal): Use
diff --git a/ChangeLog.pre-2-10 b/ChangeLog.pre-2-10
index b6d1fe849..7fb979051 100644
--- a/ChangeLog.pre-2-10
+++ b/ChangeLog.pre-2-10
@@ -1,3 +1,17 @@
+Thu Jun  5 23:40:31 2003  Owen Taylor  <otaylor@redhat.com>
+
+	* glib/gmain.c: When dispatching a source that is
+	!CAN_RECURSE, temporarily remove any file descriptors
+	that that source has registered from the main loop, to keep
+	recursive main loops from busy-waiting if input
+	becomes available on one of those file descriptors.
+	(#112222, Christian Krause)
+
+	* glib/gmain.c (g_source_set_priority): Properly
+	remove the source from the context's source list
+	and reinsert it sorted, rather than simply setting
+	source->next/prev to NULL! (#114274)
+
 2003-06-06  Matthias Clasen  <maclas@gmx.de>
 
 	* glib/gstring.c (g_string_append_printf_internal): Use
diff --git a/ChangeLog.pre-2-12 b/ChangeLog.pre-2-12
index b6d1fe849..7fb979051 100644
--- a/ChangeLog.pre-2-12
+++ b/ChangeLog.pre-2-12
@@ -1,3 +1,17 @@
+Thu Jun  5 23:40:31 2003  Owen Taylor  <otaylor@redhat.com>
+
+	* glib/gmain.c: When dispatching a source that is
+	!CAN_RECURSE, temporarily remove any file descriptors
+	that that source has registered from the main loop, to keep
+	recursive main loops from busy-waiting if input
+	becomes available on one of those file descriptors.
+	(#112222, Christian Krause)
+
+	* glib/gmain.c (g_source_set_priority): Properly
+	remove the source from the context's source list
+	and reinsert it sorted, rather than simply setting
+	source->next/prev to NULL! (#114274)
+
 2003-06-06  Matthias Clasen  <maclas@gmx.de>
 
 	* glib/gstring.c (g_string_append_printf_internal): Use
diff --git a/ChangeLog.pre-2-4 b/ChangeLog.pre-2-4
index b6d1fe849..7fb979051 100644
--- a/ChangeLog.pre-2-4
+++ b/ChangeLog.pre-2-4
@@ -1,3 +1,17 @@
+Thu Jun  5 23:40:31 2003  Owen Taylor  <otaylor@redhat.com>
+
+	* glib/gmain.c: When dispatching a source that is
+	!CAN_RECURSE, temporarily remove any file descriptors
+	that that source has registered from the main loop, to keep
+	recursive main loops from busy-waiting if input
+	becomes available on one of those file descriptors.
+	(#112222, Christian Krause)
+
+	* glib/gmain.c (g_source_set_priority): Properly
+	remove the source from the context's source list
+	and reinsert it sorted, rather than simply setting
+	source->next/prev to NULL! (#114274)
+
 2003-06-06  Matthias Clasen  <maclas@gmx.de>
 
 	* glib/gstring.c (g_string_append_printf_internal): Use
diff --git a/ChangeLog.pre-2-6 b/ChangeLog.pre-2-6
index b6d1fe849..7fb979051 100644
--- a/ChangeLog.pre-2-6
+++ b/ChangeLog.pre-2-6
@@ -1,3 +1,17 @@
+Thu Jun  5 23:40:31 2003  Owen Taylor  <otaylor@redhat.com>
+
+	* glib/gmain.c: When dispatching a source that is
+	!CAN_RECURSE, temporarily remove any file descriptors
+	that that source has registered from the main loop, to keep
+	recursive main loops from busy-waiting if input
+	becomes available on one of those file descriptors.
+	(#112222, Christian Krause)
+
+	* glib/gmain.c (g_source_set_priority): Properly
+	remove the source from the context's source list
+	and reinsert it sorted, rather than simply setting
+	source->next/prev to NULL! (#114274)
+
 2003-06-06  Matthias Clasen  <maclas@gmx.de>
 
 	* glib/gstring.c (g_string_append_printf_internal): Use
diff --git a/ChangeLog.pre-2-8 b/ChangeLog.pre-2-8
index b6d1fe849..7fb979051 100644
--- a/ChangeLog.pre-2-8
+++ b/ChangeLog.pre-2-8
@@ -1,3 +1,17 @@
+Thu Jun  5 23:40:31 2003  Owen Taylor  <otaylor@redhat.com>
+
+	* glib/gmain.c: When dispatching a source that is
+	!CAN_RECURSE, temporarily remove any file descriptors
+	that that source has registered from the main loop, to keep
+	recursive main loops from busy-waiting if input
+	becomes available on one of those file descriptors.
+	(#112222, Christian Krause)
+
+	* glib/gmain.c (g_source_set_priority): Properly
+	remove the source from the context's source list
+	and reinsert it sorted, rather than simply setting
+	source->next/prev to NULL! (#114274)
+
 2003-06-06  Matthias Clasen  <maclas@gmx.de>
 
 	* glib/gstring.c (g_string_append_printf_internal): Use
diff --git a/glib/gmain.c b/glib/gmain.c
index 4a66ee095..45ecb5ff6 100644
--- a/glib/gmain.c
+++ b/glib/gmain.c
@@ -175,6 +175,8 @@ struct _GPollRec
 #endif
 
 #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_UNREF(source, context)                       \
    G_STMT_START {                                           \
@@ -887,14 +889,17 @@ g_source_destroy_internal (GSource      *source,
 	  old_cb_funcs->unref (old_cb_data);
 	  LOCK_CONTEXT (context);
 	}
-      
-      tmp_list = source->poll_fds;
-      while (tmp_list)
+
+      if (!SOURCE_BLOCKED (source))
 	{
-	  g_main_context_remove_poll_unlocked (context, tmp_list->data);
-	  tmp_list = tmp_list->next;
+	  tmp_list = source->poll_fds;
+	  while (tmp_list)
+	    {
+	      g_main_context_remove_poll_unlocked (context, tmp_list->data);
+	      tmp_list = tmp_list->next;
+	    }
 	}
-      
+	  
       g_source_unref_internal (source, context, TRUE);
     }
 
@@ -1000,7 +1005,8 @@ g_source_add_poll (GSource *source,
 
   if (context)
     {
-      g_main_context_add_poll_unlocked (context, source->priority, fd);
+      if (!SOURCE_BLOCKED (source))
+	g_main_context_add_poll_unlocked (context, source->priority, fd);
       UNLOCK_CONTEXT (context);
     }
 }
@@ -1032,7 +1038,8 @@ g_source_remove_poll (GSource *source,
 
   if (context)
     {
-      g_main_context_remove_poll_unlocked (context, fd);
+      if (!SOURCE_BLOCKED (source))
+	g_main_context_remove_poll_unlocked (context, fd);
       UNLOCK_CONTEXT (context);
     }
 }
@@ -1186,16 +1193,22 @@ g_source_set_priority (GSource  *source,
 
   if (context)
     {
-      source->next = NULL;
-      source->prev = NULL;
-      
-      tmp_list = source->poll_fds;
-      while (tmp_list)
+      /* Remove the source from the context's source and then
+       * add it back so it is sorted in the correct plcae
+       */
+      g_source_list_remove (source, source->context);
+      g_source_list_add (source, source->context);
+
+      if (!SOURCE_BLOCKED (source))
 	{
-	  g_main_context_remove_poll_unlocked (context, tmp_list->data);
-	  g_main_context_add_poll_unlocked (context, priority, tmp_list->data);
-      
-	  tmp_list = tmp_list->next;
+	  tmp_list = source->poll_fds;
+	  while (tmp_list)
+	    {
+	      g_main_context_remove_poll_unlocked (context, tmp_list->data);
+	      g_main_context_add_poll_unlocked (context, priority, tmp_list->data);
+	      
+	      tmp_list = tmp_list->next;
+	    }
 	}
       
       UNLOCK_CONTEXT (source->context);
@@ -1622,6 +1635,43 @@ g_get_current_time (GTimeVal *result)
 
 /* Running the main loop */
 
+/* Temporarily remove all this source's file descriptors from the
+ * poll(), so that if data comes available for one of the file descriptors
+ * we don't continually spin in the poll()
+ */
+/* HOLDS: source->context's lock */
+void
+block_source (GSource *source)
+{
+  GSList *tmp_list;
+
+  g_return_if_fail (!SOURCE_BLOCKED (source));
+
+  tmp_list = source->poll_fds;
+  while (tmp_list)
+    {
+      g_main_context_remove_poll_unlocked (source->context, tmp_list->data);
+      tmp_list = tmp_list->next;
+    }
+}
+
+/* HOLDS: source->context's lock */
+void
+unblock_source (GSource *source)
+{
+  GSList *tmp_list;
+  
+  g_return_if_fail (!SOURCE_BLOCKED (source)); /* Source already unblocked */
+  g_return_if_fail (!SOURCE_DESTROYED (source));
+  
+  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;
+    }
+}
+
 /* HOLDS: context's lock */
 static void
 g_main_dispatch (GMainContext *context)
@@ -1657,6 +1707,9 @@ g_main_dispatch (GMainContext *context)
 	  if (cb_funcs)
 	    cb_funcs->ref (cb_data);
 	  
+	  if ((source->flags & G_SOURCE_CAN_RECURSE) == 0)
+	    block_source (source);
+	  
 	  was_in_call = source->flags & G_HOOK_FLAG_IN_CALL;
 	  source->flags |= G_HOOK_FLAG_IN_CALL;
 
@@ -1676,6 +1729,10 @@ 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))
+	    unblock_source (source);
+	  
 	  /* Note: this depends on the fact that we can't switch
 	   * sources from one main context to another
 	   */
@@ -1964,7 +2021,7 @@ g_main_context_prepare (GMainContext *context,
 	  SOURCE_UNREF (source, context);
 	  break;
 	}
-      if ((source->flags & G_HOOK_FLAG_IN_CALL) && !(source->flags & G_SOURCE_CAN_RECURSE))
+      if (SOURCE_BLOCKED (source))
 	goto next;
 
       if (!(source->flags & G_SOURCE_READY))
@@ -2152,7 +2209,7 @@ g_main_context_check (GMainContext *context,
 	  SOURCE_UNREF (source, context);
 	  break;
 	}
-      if ((source->flags & G_HOOK_FLAG_IN_CALL) && !(source->flags & G_SOURCE_CAN_RECURSE))
+      if (SOURCE_BLOCKED (source))
 	goto next;
 
       if (!(source->flags & G_SOURCE_READY))