Change event code to use gdbpy_ref

This changes the event code in the Python layer to use
gdbpy_ref, simplifying the logic in many places.

It also changes evpy_emit_event not to steal a reference to its
argument.  This is simpler to do now that gdbpy_ref is in use;
it's also a reasonable cleanup in its own right.  While doing this I
realized that evpy_emit_event should not be calling gdbpy_print_stack
(all the outermost callers do this if needed), so I removed this as
well.

2017-01-10  Tom Tromey  <tom@tromey.com>

	* python/py-threadevent.c (create_thread_event_object): Use
	gdbpy_ref.
	* python/py-stopevent.c (create_stop_event_object): Simplify.
	(emit_stop_event): Use gdbpy_ref.
	* python/py-signalevent.c (create_signal_event_object): Use
	gdbpy_ref.
	* python/py-newobjfileevent.c (create_new_objfile_event_object)
	(emit_new_objfile_event, create_clear_objfiles_event_object)
	(emit_clear_objfiles_event): Use gdbpy_ref.
	* python/py-infevents.c (create_inferior_call_event_object)
	(create_register_changed_event_object)
	(create_memory_changed_event_object, emit_inferior_call_event)
	(emit_memory_changed_event, emit_register_changed_event): Use
	gdbpy_ref.
	* python/py-exitedevent.c (create_exited_event_object)
	(emit_exited_event): Use gdbpy_ref.
	* python/py-event.h (evpy_emit_event): Remove
	CPYCHECKER_STEALS_REFERENCE_TO_ARG annotation.
	* python/py-event.c (evpy_emit_event): Use gdbpy_ref.
	* python/py-continueevent.c (emit_continue_event): Use
	gdbpy_ref.
	* python/py-breakpoint.c (gdbpy_breakpoint_created)
	(gdbpy_breakpoint_deleted, gdbpy_breakpoint_modified): Use
	gdbpy_ref.
	* python/py-bpevent.c (create_breakpoint_event_object): Use
	gdbpy_ref.

1 files changed, 7 insertions, 12 deletions

diff --git a/gdb/python/py-threadevent.c b/gdb/python/py-threadevent.c
index edcf3c0..bba974b 100644
--- a/gdb/python/py-threadevent.c
+++ b/gdb/python/py-threadevent.c
@@ -51,26 +51,21 @@ PyObject *
 create_thread_event_object (PyTypeObject *py_type)
 {
   PyObject *thread = NULL;
-  PyObject *thread_event_obj = NULL;
 
-  thread_event_obj = create_event_object (py_type);
-  if (!thread_event_obj)
-    goto fail;
+  gdbpy_ref thread_event_obj (create_event_object (py_type));
+  if (thread_event_obj == NULL)
+    return NULL;
 
   thread = get_event_thread ();
   if (!thread)
-    goto fail;
+    return NULL;
 
-  if (evpy_add_attribute (thread_event_obj,
+  if (evpy_add_attribute (thread_event_obj.get (),
                           "inferior_thread",
                           thread) < 0)
-    goto fail;
+    return NULL;
 
-  return thread_event_obj;
-
-  fail:
-   Py_XDECREF (thread_event_obj);
-   return NULL;
+  return thread_event_obj.release ();
 }
 
 GDBPY_NEW_EVENT_TYPE (thread,