bug#64658: 30.0.50; NotifyGrab and NotifyUngrab should be filtered with XInput2

[Zigit Zo]

They're both 0, so the ~mode~ member is chosen :( For convenient, posted
all members when FocusIn event triggered, the last one is the cause of
~selected-frame~ changes.

#+begin_src
Thread 1 "emacs" hit Breakpoint 5, xi_handle_focus_change 
(dpyinfo=0x558ec6140c00) at ../../src/xterm.c:13068
13068   {
#2  0x0000558ec403e631 in event_handler_gdk (gxev=0x7ffd3ebb6080, ev=<optimized out>, 
data=<optimized out>)
    at ../../src/xterm.c:17671
$282 = (struct frame *) 0x558ec5dd5da0
"emacs - FRAME 1 TITLE"
(gdb) p *(XIFocusInEvent*) ((XEvent*) gxev)->xcookie.data
$284 = {
  type = 35,
  serial = 265494,
  send_event = 0,
  display = 0x558ec5ecb250,
  extension = 131,
  evtype = 9,
  time = 170569789,
  deviceid = 3,
  sourceid = 3,
  detail = 3,
  root = 483,
  event = 79691928,
  child = 0,
  root_x = 2769,
  root_y = 993,
  event_x = 2751,
  event_y = 879,
  mode = 3,
  focus = 0,
  same_screen = 1,
  buttons = {
    mask_len = 4,
    mask = 0x558ec9481958 ""
  },
  mods = {
    base = 64,
    latched = 0,
    locked = 0,
    effective = 64
  },
  group = {
    base = 0,
    latched = 0,
    locked = 0,
    effective = 0
  }
}

Thread 1 "emacs" hit Breakpoint 5, xi_handle_focus_change 
(dpyinfo=0x558ec6140c00) at ../../src/xterm.c:13068
13068   {
#2  0x0000558ec403e631 in event_handler_gdk (gxev=0x7ffd3ebb6080, ev=<optimized out>, 
data=<optimized out>)
    at ../../src/xterm.c:17671
$289 = (struct frame *) 0x558ec5dd5da0
"emacs - FRAME 1 TITLE"
(gdb) p *(XIFocusInEvent*) ((XEvent*) gxev)->xcookie.data
$291 = {
  type = 35,
  serial = 270527,
  send_event = 0,
  display = 0x558ec5ecb250,
  extension = 131,
  evtype = 9,
  time = 170569915,
  deviceid = 3,
  sourceid = 3,
  detail = 0,
  root = 483,
  event = 79691928,
  child = 0,
  root_x = 2769,
  root_y = 993,
  event_x = 2751,
  event_y = 879,
  mode = 2,
  focus = 0,
  same_screen = 1,
  buttons = {
    mask_len = 4,
    mask = 0x558ecc272658 ""
  },
  mods = {
    base = 64,
    latched = 0,
    locked = 0,
    effective = 64
  },
  group = {
    base = 0,
    latched = 0,
    locked = 0,
    effective = 0
  }
}

Thread 1 "emacs" hit Breakpoint 5, xi_handle_focus_change 
(dpyinfo=0x558ec6140c00) at ../../src/xterm.c:13068
13068   {
#2  0x0000558ec403e631 in event_handler_gdk (gxev=0x7ffd3ebb6080, ev=<optimized out>, 
data=<optimized out>)
    at ../../src/xterm.c:17671
$295 = (struct frame *) 0x558ecde5baf0
"emacs - FRAME 2 TITLE UNFOCUSED"
(gdb) p *(XIFocusInEvent*) ((XEvent*) gxev)->xcookie.data
$297 = {
  type = 35,
  serial = 270527,
  send_event = 0,
  display = 0x558ec5ecb250,
  extension = 131,
  evtype = 9,
  time = 170570127,
  deviceid = 3,
  sourceid = 3,
  detail = 5,
  root = 483,
  event = 79692372,
  child = 0,
  root_x = 2769,
  root_y = 993,
  event_x = 459,
  event_y = 879,
  mode = 1,
  focus = 0,
  same_screen = 1,
  buttons = {
    mask_len = 4,
    mask = 0x558ecb779b88 ""
  },
  mods = {
    base = 64,
    latched = 0,
    locked = 0,
    effective = 64
  },
  group = {
    base = 0,
    latched = 0,
    locked = 0,
    effective = 0
  }
}
#+end_sr

Hope this will be useful.

在 2023/7/16 17:09, Po Lu 写道:

> 左 智杰 <hardirq@outlook.com> writes:
>
> > In i3wm + xfce4 setup, when multiple frames opened, switch between frames
> > using only keyboard, and leave the mouse as:
> >
> > +-----------------+  +-----------------+
> > |                 |  |                 |
> > |                 |  |                 |
> > |                 |  |                 |
> > |                 |  |                 |
> > |                 |  |                 |
> > |                 |  |                 |
> > |     FRAME 1     |  |     FRAME 2     |
> > |    *FOCUSED*    |  |   *UNFOCUSED*   |
> > |                 |  |          ^      |
> > |                 |  |          |      |
> > |                 |  |        MOUSE    |
> > |                 |  |         HERE    |
> > |                 |  |                 |
> > +-----------------+  +-----------------+
> >
> > This will make the ~emacsclient -e '(selected-frame)'~ returns wrong frame, due 
> > to
> > XInput2 sends a ~NotifyGrab~ with the unfocused frame, making Emacs selects it.
> >
> > We've make a small but ugly changes to fix this issue:
> >
> > #+begin_src
> > diff --git a/src/xterm.c b/src/xterm.c
> > index 9ecead03b0..d4836afeeb 100644
> > --- a/src/xterm.c
> > +++ b/src/xterm.c
> > @@ -13193,6 +13193,11 @@ xi_focus_handle_for_device (struct x_display_info 
> > *dpyinfo,
> >     if (!device)
> >       return;
> >   
> > +  /* Same as x_detect_focus_change, issue persists in XInput2. */
> > +  if (event->evtype == XI_FocusIn || event->evtype == XI_FocusOut)
> > +    if (event->mode == XINotifyGrab || event->mode == XINotifyUngrab)
> > +      return;
> > +
> >     switch (event->evtype)
> >       {
> >       case XI_FocusIn:
> > #+end_src
> >
> > Wonder if we're correct?
> I don't want this hack in the input extension code, because it is much
> more sensitive to inconsistencies in the keyboard focus state.
>
> What is the value of event->send_event for these unwanted focus events?