Fix bug that munged selection info

On some optimizing C compilers, copying a structure did not
copy the padding bytes between elements, and the type punning
between struct input_data and struct selection_input_data did
not work.  Change the C code to use a proper union type instead.
Problem reported by YAMAMOTO Mitsuharu (Bug#20756).
* src/keyboard.c (kbd_buffer, kbd_fetch_ptr, kbd_store_ptr)
(readable_events, discard_mouse_events, kbd_buffer_events_waiting)
(kbd_buffer_get_event, process_special_events, stuff_buffered_input)
(mark_kboards):
Use union buffered_input_event, not struct input_event.
(clear_event, deliver_input_available_signal, process_special_events):
Remove unnecessary forward decls.
(kbd_buffer_store_buffered_event): New function, mostly just the
old kbd_buffer_store_event_hold, except its argument is of type
union buffered_input_event, not struct input_event.
(kbd_buffer_unget_event): Define only if HAVE_X11, since it's
not needed otherwise.  Argument is now of type
struct selection_input_event *, not struct input_event *.
All callers changed.
(clear_event): Arg is now of type union buffered_input_event *,
not struct input_event *.  All callers changed.
* src/keyboard.h [HAVE_X11]: Include "xterm.h".
(union buffered_input_event): New type.
(kbd_buffer_store_event_hold): Now an inline function,
defined here.
* src/termhooks.h (EVENT_KIND_WIDTH): New constant.
(struct input_event): Use it.
* src/xselect.c (struct selection_event_queue):
Make elements be of type struct selection_input_event,
not struct input_event.
(selection_input_event_equal): New static function.
(x_queue_event): Use it.
(x_queue_event, x_decline_selection_request)
(x_selection_current_request, x_reply_selection_request)
(x_handle_selection_request, x_handle_selection_clear)
(x_handle_selection_event): Use struct selection_input_event,
not struct input_event.  All callers changed.
(x_convert_selection): Omit unused first arg.  All callers changed.
(Fx_disown_selection_internal): Omit unnecessary union.
* src/xterm.c (handle_one_xevent): Use new union buffered_input_event
rather than rolling our own equivalent.  Prefer sie.kind when
setting up that kind of structure.
Call kbd_buffer_store_buffered_event, not kbd_buffer_store_event_hold.
* src/xterm.h (struct selection_input_event: Use EVENT_KIND_WIDTH.
(SELECTION_EVENT_DISPLAY, SELECTION_EVENT_DPYINFO)
(SELECTION_EVENT_REQUESTOR, SELECTION_EVENT_SELECTION)
(SELECTION_EVENT_TARGET, SELECTION_EVENT_PROPERTY)
(SELECTION_EVENT_TIME, x_handle_selection_event):
Arg is now of type struct selection_input_event *)
not struct input_event *.  All callers changed.

1 files changed, 10 insertions, 10 deletions

diff --git a/src/xterm.h b/src/xterm.h
index 3081c1653e3..5622344d97c 100644
--- a/src/xterm.h
+++ b/src/xterm.h
@@ -960,7 +960,7 @@ struct scroll_bar
 
 struct selection_input_event
 {
-  int kind;
+  ENUM_BF (event_kind) kind : EVENT_KIND_WIDTH;
   struct x_display_info *dpyinfo;
   /* We spell it with an "o" here because X does.  */
   Window requestor;
@@ -970,23 +970,23 @@ struct selection_input_event
 
 /* Unlike macros below, this can't be used as an lvalue.  */
 INLINE Display *
-SELECTION_EVENT_DISPLAY (struct input_event *ev)
+SELECTION_EVENT_DISPLAY (struct selection_input_event *ev)
 {
-  return ((struct selection_input_event *) ev)->dpyinfo->display;
+  return ev->dpyinfo->display;
 }
 #define SELECTION_EVENT_DPYINFO(eventp) \
-  (((struct selection_input_event *) (eventp))->dpyinfo)
+  ((eventp)->dpyinfo)
 /* We spell it with an "o" here because X does.  */
 #define SELECTION_EVENT_REQUESTOR(eventp)	\
-  (((struct selection_input_event *) (eventp))->requestor)
+  ((eventp)->requestor)
 #define SELECTION_EVENT_SELECTION(eventp)	\
-  (((struct selection_input_event *) (eventp))->selection)
+  ((eventp)->selection)
 #define SELECTION_EVENT_TARGET(eventp)	\
-  (((struct selection_input_event *) (eventp))->target)
+  ((eventp)->target)
 #define SELECTION_EVENT_PROPERTY(eventp)	\
-  (((struct selection_input_event *) (eventp))->property)
+  ((eventp)->property)
 #define SELECTION_EVENT_TIME(eventp)	\
-  (((struct selection_input_event *) (eventp))->time)
+  ((eventp)->time)
 
 /* From xfns.c.  */
 
@@ -1079,7 +1079,7 @@ extern void x_clear_under_internal_border (struct frame *f);
 
 extern void x_handle_property_notify (const XPropertyEvent *);
 extern void x_handle_selection_notify (const XSelectionEvent *);
-extern void x_handle_selection_event (struct input_event *);
+extern void x_handle_selection_event (struct selection_input_event *);
 extern void x_clear_frame_selections (struct frame *);
 
 extern void x_send_client_event (Lisp_Object display,