Modifier key not detected

[GoogleCodeExporter]

What steps will reproduce the problem?
I've mapped my ISO_Level3_Shift button, which is the right Alt button on my
keyboard, to be mod5:
$ xmodmap
xmodmap:  up to 3 keys per modifier, (keycodes in parentheses):

shift       Shift_L (0x32),  Shift_R (0x3e)
lock      
control     Control_L (0x25),  Control_L (0x42),  Control_R (0x69)
mod1        Alt_L (0x40),  Meta_L (0xcd)
mod2        Num_Lock (0x4d)
mod3      
mod4        Super_L (0xce),  Hyper_L (0xcf)
mod5        ISO_Level3_Shift (0x5c),  Mode_switch (0xcb)

So that when I press my Alt button on the right, xev sees:
KeyPress event, serial 25, synthetic NO, window 0x1e00001,
    root 0xa5, subw 0x0, time 358194927, (621,436), root:(622,455),
    state 0x0, keycode 108 (keysym 0xfe03, ISO_Level3_Shift), same_screen YES,
    XKeysymToKeycode returns keycode: 92
    XLookupString gives 0 bytes:
    XmbLookupString gives 0 bytes:
    XFilterEvent returns: False

So it mentions two keycodes, 108 and 92.  Keycode 92 is detected by xdotool
as mod5, but the loop in xdo_active_modifiers_to_keycode_list sees it as
108, and so doesn't recognize it as a modifier.  This causes a problem for
me when I try to port the clearmodifiers feature to mouse buttons, because
the modifier key is not detected and is still active, so it sends both the
modifier and the button press.

I changed the code:

--- orig/xdotool-20090710/xdo.c 2009-07-10 00:55:14.000000000 -0700
+++ changed/xdotool-20090710/xdo.c      2009-07-30 09:52:08.000000000 -0700
@@ -1151,14 +1151,18 @@
   char keymap[32]; /* keycode map: 256 bits */
   int keys_size = 10;
   int keycode = 0;
+  int realKeycode = 0;
+  KeySym sym;
   *nkeys = 0;
   *keys = malloc(keys_size * sizeof(charcodemap_t));

   XQueryKeymap(xdo->xdpy, keymap);

   for (keycode = 0; keycode < 256; keycode++) {
+    sym = XKeycodeToKeysym(xdo->xdpy, keycode, 0);
+    realKeycode = XKeysymToKeycode(xdo->xdpy, sym);
     if ((keymap[(keycode / 8)] & (1 << (keycode % 8))) \
-        && _xdo_cached_keycode_to_modifier(xdo, keycode)) {
+        && _xdo_cached_keycode_to_modifier(xdo, realKeycode)) {
       /* This keycode is active and is a modifier */

       (*keys)[*nkeys].code = keycode;

and that seems to fix it.  I don't actually know much about X keycodes and
keysyms, so I'm not sure if this is the right way to do this.

Original issue reported on code.google.com by andrew.a...@gmail.com on 30 Jul 2009 at 4:54

[GoogleCodeExporter]

That's funky indeed. Can you add the contents of 'xmodmap -pke' here?

Reading over the functions involved in this doesn't point out anything obvious.

The 'if' statement checks if the keycode (keyboard key) is active and if it's a 
modifier. the _xdo_cached_keycode_to_modifier() function uses data from data 
populated using _xdo_query_keycode_to_modifier, which walks data given by 
XGetModifierMapping.

Either way, it seems like a bug. I'll see if I can reproduce it. If not, I'll 
give 
you some test code to help me inspect this more.

Original comment by jls.semi...@gmail.com on 1 Jan 2010 at 4:17