* src/keyboard.c: Fix bug#5803.

A long time ago, `read_key_sequence` used to read the keymaps at the
start, so if something happened between this start and the moment
the user actually hits a key, `read_key_sequence` could end up using
the wrong keymaps.  To work around this problem, the code used
`record_asynch_buffer_change` to try and trigger `read_key_sequence`
to re-read the keymaps in some known cases.

Several years ago, `read_key_sequence` was changed so as to read the keymaps
only once the user hits a key, making this machinery now redundant
(and also harmful apparently in bug#5803 because it introduces
"spurious" events).

So we here remove `record_asynch_buffer_change` and the
`BUFFER_SWITCH_EVENT` and `Qbuffer_switch` pseudo-events it generated.

* src/termhooks.h (enum event_kind): Delete `BUFFER_SWITCH_EVENT`.
* src/keyboard.c: (record_asynch_buffer_change): Delete function.
(syms_of_keyboard): Delete `Qbuffer_switch`.
(force_auto_save_soon, readable_events)
(kbd_buffer_store_buffered_event, kbd_buffer_get_event)
(make_lispy_event):
* src/xterm.c (handle_one_xevent):
* src/w32term.c (w32_read_socket):
* src/process.c (wait_reading_process_output)
(read_and_dispose_of_process_output, exec_sentinel): Simplify accordingly.

1 files changed, 0 insertions, 38 deletions

diff --git a/src/process.c b/src/process.c
index bf64ead24e5..48b727d9e3b 100644
--- a/src/process.c
+++ b/src/process.c
@@ -5333,14 +5333,6 @@ wait_reading_process_output (intmax_t time_limit, int nsecs, int read_kbd,
 
               timer_delay = timer_check ();
 
-              /* If a timer has run, this might have changed buffers
-                 an alike.  Make read_key_sequence aware of that.  */
-              if (timers_run != old_timers_run
-                  && (old_buffer != current_buffer
-                      || !EQ (old_window, selected_window))
-                  && waiting_for_user_input_p == -1)
-                record_asynch_buffer_change ();
-
               if (timers_run != old_timers_run && do_display)
                 /* We must retry, since a timer may have requeued itself
                    and that could alter the time_delay.  */
@@ -5706,14 +5698,6 @@ wait_reading_process_output (intmax_t time_limit, int nsecs, int read_kbd,
                 leave = true;
             }
 
-          /* If a timer has run, this might have changed buffers
-             an alike.  Make read_key_sequence aware of that.  */
-          if (timers_run != old_timers_run
-              && waiting_for_user_input_p == -1
-              && (old_buffer != current_buffer
-              || !EQ (old_window, selected_window)))
-            record_asynch_buffer_change ();
-
           if (leave)
             break;
         }
@@ -6213,18 +6197,6 @@ read_and_dispose_of_process_output (struct Lisp_Process *p, char *chars,
   /* Restore waiting_for_user_input_p as it was
      when we were called, in case the filter clobbered it.  */
   waiting_for_user_input_p = waiting;
-
-#if 0 /* Call record_asynch_buffer_change unconditionally,
-         because we might have changed minor modes or other things
-         that affect key bindings.  */
-  if (! EQ (Fcurrent_buffer (), obuffer)
-      || ! EQ (current_buffer->keymap, okeymap))
-#endif
-    /* But do it only if the caller is actually going to read events.
-       Otherwise there's no need to make him wake up, and it could
-       cause trouble (for example it would make sit_for return).  */
-    if (waiting_for_user_input_p == -1)
-      record_asynch_buffer_change ();
 }
 
 DEFUN ("internal-default-process-filter", Finternal_default_process_filter,
@@ -7390,16 +7362,6 @@ exec_sentinel (Lisp_Object proc, Lisp_Object reason)
      when we were called, in case the filter clobbered it.  */
   waiting_for_user_input_p = waiting;
 
-#if 0
-  if (! EQ (Fcurrent_buffer (), obuffer)
-      || ! EQ (current_buffer->keymap, okeymap))
-#endif
-    /* But do it only if the caller is actually going to read events.
-       Otherwise there's no need to make him wake up, and it could
-       cause trouble (for example it would make sit_for return).  */
-    if (waiting_for_user_input_p == -1)
-      record_asynch_buffer_change ();
-
   unbind_to (count, Qnil);
 }