[PATCH 1/4] Change evpy_emit_event to accept a gdbpy_opt_borrowed_ref

This changes evpy_emit_event to accept a gdbpy_opt_borrowed_ref.  An
"opt" type is used because one caller explicitly passes NULL, meaning
that the event should be emitted without a payload object.

This patch is a small step toward using the safety API in event
generation, though for the time being it mainly allows the removal of
calls to "get".
---
 gdb/python/py-breakpoint.c      | 5 ++---
 gdb/python/py-connection.c      | 2 +-
 gdb/python/py-continueevent.c   | 2 +-
 gdb/python/py-corefile.c        | 2 +-
 gdb/python/py-event.c           | 2 +-
 gdb/python/py-event.h           | 7 ++++++-
 gdb/python/py-exitedevent.c     | 2 +-
 gdb/python/py-inferior.c        | 8 ++++----
 gdb/python/py-infevents.c       | 6 +++---
 gdb/python/py-newobjfileevent.c | 6 +++---
 gdb/python/py-progspace.c       | 4 ++--
 gdb/python/py-stopevent.c       | 2 +-
 gdb/python/py-threadevent.c     | 2 +-
 gdb/python/py-tui.c             | 2 +-
 gdb/python/python.c             | 2 +-
 15 files changed, 29 insertions(+), 25 deletions(-)

diff --git a/gdb/python/py-breakpoint.c b/gdb/python/py-breakpoint.c
index ecb42cee5f9..b628e14ae4e 100644
--- a/gdb/python/py-breakpoint.c
+++ b/gdb/python/py-breakpoint.c
@@ -1283,8 +1283,7 @@ gdbpy_breakpoint_created (struct breakpoint *bp)
 
   if (!evregpy_no_listeners_p (gdb_py_events.breakpoint_created))
     {
-      if (evpy_emit_event ((PyObject *) newbp,
-			   gdb_py_events.breakpoint_created) < 0)
+      if (evpy_emit_event (newbp, gdb_py_events.breakpoint_created) < 0)
 	gdbpy_print_stack ();
     }
 }
@@ -1312,7 +1311,7 @@ gdbpy_breakpoint_deleted (struct breakpoint *b)
 
 	  if (!evregpy_no_listeners_p (gdb_py_events.breakpoint_deleted))
 	    {
-	      if (evpy_emit_event ((PyObject *) bp_obj.get (),
+	      if (evpy_emit_event (bp_obj,
 				   gdb_py_events.breakpoint_deleted) < 0)
 		gdbpy_print_stack ();
 	    }
diff --git a/gdb/python/py-connection.c b/gdb/python/py-connection.c
index bc738669b79..99bed238b6c 100644
--- a/gdb/python/py-connection.c
+++ b/gdb/python/py-connection.c
@@ -146,7 +146,7 @@ emit_connection_event (process_stratum_target *target,
   if (evpy_add_attribute (event_obj.get (), "connection", conn.get ()) < 0)
     return -1;
 
-  return evpy_emit_event (event_obj.get (), registry);
+  return evpy_emit_event (event_obj, registry);
 }
 
 /* Callback for the connection_removed observer.  */
diff --git a/gdb/python/py-continueevent.c b/gdb/python/py-continueevent.c
index 15404157062..06d4dabadd9 100644
--- a/gdb/python/py-continueevent.c
+++ b/gdb/python/py-continueevent.c
@@ -51,6 +51,6 @@ emit_continue_event (ptid_t ptid)
 
   gdbpy_ref<> event = create_continue_event_object (ptid);
   if (event != NULL)
-    return evpy_emit_event (event.get (), gdb_py_events.cont);
+    return evpy_emit_event (event, gdb_py_events.cont);
   return -1;
 }
diff --git a/gdb/python/py-corefile.c b/gdb/python/py-corefile.c
index fc5b4889fdc..542bc05f560 100644
--- a/gdb/python/py-corefile.c
+++ b/gdb/python/py-corefile.c
@@ -346,7 +346,7 @@ emit_corefile_changed_event (inferior *inf)
 			     inf_obj.get ()) < 0)
     return -1;
 
-  return evpy_emit_event (event_obj.get (), gdb_py_events.corefile_changed);
+  return evpy_emit_event (event_obj, gdb_py_events.corefile_changed);
 }
 
 /* Callback from gdb::observers::core_file_changed.  The core file for
diff --git a/gdb/python/py-event.c b/gdb/python/py-event.c
index a7aa46dcb6f..6dd6f3bf356 100644
--- a/gdb/python/py-event.c
+++ b/gdb/python/py-event.c
@@ -62,7 +62,7 @@ gdbpy_initialize_event ()
    returns 0 if emit is successful -1 otherwise.  */
 
 int
-evpy_emit_event (PyObject *event,
+evpy_emit_event (gdbpy_opt_borrowed_ref<> event,
 		 eventregistry_object *registry)
 {
   Py_ssize_t i;
diff --git a/gdb/python/py-event.h b/gdb/python/py-event.h
index ec2e7bc03c5..c8fbbf3add6 100644
--- a/gdb/python/py-event.h
+++ b/gdb/python/py-event.h
@@ -53,7 +53,12 @@ extern int emit_inferior_call_event (inferior_call_kind kind,
 extern int emit_register_changed_event (const frame_info_ptr &frame,
 					int regnum);
 extern int emit_memory_changed_event (CORE_ADDR addr, ssize_t len);
-extern int evpy_emit_event (PyObject *event,
+
+/* Emit an event to a given event registry.  Return 0 on success, -1
+   with the Python exception set on failure.  gdbpy_opt_borrowed_ref
+   is used; if NULL is passed, then the event will be emitted without
+   a payload.  */
+extern int evpy_emit_event (gdbpy_opt_borrowed_ref<> event,
 			    eventregistry_object *registry);
 
 /* Emits a thread exit event for THREAD */
diff --git a/gdb/python/py-exitedevent.c b/gdb/python/py-exitedevent.c
index d15f768ab79..866adb7ff8b 100644
--- a/gdb/python/py-exitedevent.c
+++ b/gdb/python/py-exitedevent.c
@@ -59,7 +59,7 @@ emit_exited_event (const LONGEST *exit_code, struct inferior *inf)
   gdbpy_ref<> event = create_exited_event_object (exit_code, inf);
 
   if (event != NULL)
-    return evpy_emit_event (event.get (), gdb_py_events.exited);
+    return evpy_emit_event (event, gdb_py_events.exited);
 
   return -1;
 }
diff --git a/gdb/python/py-inferior.c b/gdb/python/py-inferior.c
index 426aec31e9e..5f0019b7b86 100644
--- a/gdb/python/py-inferior.c
+++ b/gdb/python/py-inferior.c
@@ -257,7 +257,7 @@ python_new_inferior (struct inferior *inf)
   if (event == NULL
       || evpy_add_attribute (event.get (), "inferior",
 			     (PyObject *) inf_obj.get ()) < 0
-      || evpy_emit_event (event.get (), gdb_py_events.new_inferior) < 0)
+      || evpy_emit_event (event, gdb_py_events.new_inferior) < 0)
     gdbpy_print_stack ();
 }
 
@@ -285,7 +285,7 @@ python_inferior_deleted (struct inferior *inf)
   if (event == NULL
       || evpy_add_attribute (event.get (), "inferior",
 			     (PyObject *) inf_obj.get ()) < 0
-      || evpy_emit_event (event.get (), gdb_py_events.inferior_deleted) < 0)
+      || evpy_emit_event (event, gdb_py_events.inferior_deleted) < 0)
     gdbpy_print_stack ();
 }
 
@@ -339,7 +339,7 @@ add_thread_object (struct thread_info *tp)
      (PyObject *) ins_result.first->second.get ());
 
   if (event == NULL
-      || evpy_emit_event (event.get (), gdb_py_events.new_thread) < 0)
+      || evpy_emit_event (event, gdb_py_events.new_thread) < 0)
     gdbpy_print_stack ();
 }
 
@@ -1040,7 +1040,7 @@ python_context_changed (user_selected_what selection)
       || evpy_add_attribute (event.get (), "inferior", inf_obj.get ()) < 0
       || evpy_add_attribute (event.get (), "thread", thr_obj.get ()) < 0
       || evpy_add_attribute (event.get (), "frame", frame_obj.get ()) < 0
-      || evpy_emit_event (event.get (), gdb_py_events.selected_context) < 0)
+      || evpy_emit_event (event, gdb_py_events.selected_context) < 0)
     gdbpy_print_stack ();
 }
 
diff --git a/gdb/python/py-infevents.c b/gdb/python/py-infevents.c
index 1b27987d039..db77f4593d6 100644
--- a/gdb/python/py-infevents.c
+++ b/gdb/python/py-infevents.c
@@ -127,7 +127,7 @@ emit_inferior_call_event (inferior_call_kind flag, ptid_t thread,
 
   gdbpy_ref<> event = create_inferior_call_event_object (flag, thread, addr);
   if (event != NULL)
-    return evpy_emit_event (event.get (), gdb_py_events.inferior_call);
+    return evpy_emit_event (event, gdb_py_events.inferior_call);
   return -1;
 }
 
@@ -142,7 +142,7 @@ emit_memory_changed_event (CORE_ADDR addr, ssize_t len)
 
   gdbpy_ref<> event = create_memory_changed_event_object (addr, len);
   if (event != NULL)
-    return evpy_emit_event (event.get (), gdb_py_events.memory_changed);
+    return evpy_emit_event (event, gdb_py_events.memory_changed);
   return -1;
 }
 
@@ -157,6 +157,6 @@ emit_register_changed_event (const frame_info_ptr &frame, int regnum)
 
   gdbpy_ref<> event = create_register_changed_event_object (frame, regnum);
   if (event != NULL)
-    return evpy_emit_event (event.get (), gdb_py_events.register_changed);
+    return evpy_emit_event (event, gdb_py_events.register_changed);
   return -1;
 }
diff --git a/gdb/python/py-newobjfileevent.c b/gdb/python/py-newobjfileevent.c
index 19a33d2afc6..e72e9ae67e3 100644
--- a/gdb/python/py-newobjfileevent.c
+++ b/gdb/python/py-newobjfileevent.c
@@ -48,7 +48,7 @@ emit_new_objfile_event (struct objfile *objfile)
 
   gdbpy_ref<> event = create_new_objfile_event_object (objfile);
   if (event != NULL)
-    return evpy_emit_event (event.get (), gdb_py_events.new_objfile);
+    return evpy_emit_event (event, gdb_py_events.new_objfile);
   return -1;
 }
 
@@ -85,7 +85,7 @@ emit_free_objfile_event (struct objfile *objfile)
   gdbpy_ref<> event = create_free_objfile_event_object (objfile);
   if (event == nullptr)
     return -1;
-  return evpy_emit_event (event.get (), gdb_py_events.free_objfile);
+  return evpy_emit_event (event, gdb_py_events.free_objfile);
 }
 
 
@@ -121,6 +121,6 @@ emit_clear_objfiles_event (program_space *pspace)
 
   gdbpy_ref<> event = create_clear_objfiles_event_object (pspace);
   if (event != NULL)
-    return evpy_emit_event (event.get (), gdb_py_events.clear_objfiles);
+    return evpy_emit_event (event, gdb_py_events.clear_objfiles);
   return -1;
 }
diff --git a/gdb/python/py-progspace.c b/gdb/python/py-progspace.c
index 48e52328e9c..31ea3ad8fc8 100644
--- a/gdb/python/py-progspace.c
+++ b/gdb/python/py-progspace.c
@@ -648,7 +648,7 @@ emit_executable_changed_event (eventregistry_object *registry,
 			     py_reload_p.get ()) < 0)
     return -1;
 
-  return evpy_emit_event (event_obj.get (), registry);
+  return evpy_emit_event (event_obj, registry);
 }
 
 /* Listener for the executable_changed observable, this is called when the
@@ -708,7 +708,7 @@ gdbpy_program_space_event (program_space *pspace, bool adding_p)
   if (event == nullptr
       || evpy_add_attribute (event.get (), "progspace",
 			     pspace_obj.get ()) < 0
-      || evpy_emit_event (event.get (), registry) < 0)
+      || evpy_emit_event (event, registry) < 0)
     gdbpy_print_stack ();
 }
 
diff --git a/gdb/python/py-stopevent.c b/gdb/python/py-stopevent.c
index cefcfdd0761..77db754140c 100644
--- a/gdb/python/py-stopevent.c
+++ b/gdb/python/py-stopevent.c
@@ -169,5 +169,5 @@ emit_stop_event (struct bpstat *bs, enum gdb_signal stop_signal)
 	return -1;
     }
 
-  return evpy_emit_event (stop_event_obj.get (), gdb_py_events.stop);
+  return evpy_emit_event (stop_event_obj, gdb_py_events.stop);
 }
diff --git a/gdb/python/py-threadevent.c b/gdb/python/py-threadevent.c
index 3c28aa1174a..d2998d92304 100644
--- a/gdb/python/py-threadevent.c
+++ b/gdb/python/py-threadevent.c
@@ -71,5 +71,5 @@ emit_thread_exit_event (thread_info * thread)
   if (inf_thr == nullptr)
     return -1;
 
-  return evpy_emit_event (inf_thr.get (), gdb_py_events.thread_exited);
+  return evpy_emit_event (inf_thr, gdb_py_events.thread_exited);
 }
diff --git a/gdb/python/py-tui.c b/gdb/python/py-tui.c
index 5a36814debb..0046c66d570 100644
--- a/gdb/python/py-tui.c
+++ b/gdb/python/py-tui.c
@@ -606,7 +606,7 @@ gdbpy_tui_enabled (bool state)
 
   gdbpy_ref<> code (PyBool_FromLong (state));
   if (evpy_add_attribute (event_obj.get (), "enabled", code.get ()) < 0
-      || evpy_emit_event (event_obj.get (), gdb_py_events.tui_enabled) < 0)
+      || evpy_emit_event (event_obj, gdb_py_events.tui_enabled) < 0)
     gdbpy_print_stack ();
 }
 
diff --git a/gdb/python/python.c b/gdb/python/python.c
index 7b5de98b903..5312cdbdb01 100644
--- a/gdb/python/python.c
+++ b/gdb/python/python.c
@@ -2503,7 +2503,7 @@ emit_exiting_event (int exit_code)
   if (evpy_add_attribute (event_obj.get (), "exit_code", code.get ()) < 0)
     return -1;
 
-  return evpy_emit_event (event_obj.get (), gdb_py_events.gdb_exiting);
+  return evpy_emit_event (event_obj, gdb_py_events.gdb_exiting);
 }
 
 /* Callback for the gdb_exiting observable.  EXIT_CODE is the value GDB

-- 
2.49.0