On 02/12/2010 12:09 PM, Shahar Havivi wrote:
It's not true that SDL is not sending up event like the comment say,
On Fedora 12 it behave like a toggle button, first press/release will send
caps-down event second press/release send caps-up event
>
On Ubuntu 9.10 it work like any other key, i.e. pressing caps will generate two
events down and up.
True. To see why, start at
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=317010 and
http://archive.ubuntu.com/ubuntu/pool/main/libs/libsdl1.2/libsdl1.2_1.2.13-4ubuntu4.diff.gz
-- it's a nice code reading exercise, so I'll suggest a possible
solution before pointing out the reason for this behavior. The solution
would be to put hack after hack, i.e. something like this (untested):
case 0x3a: /* caps lock */
/* SDL will usually send only 2 events instead of 4, so we
generate the missing ones. However, on Debian/Ubuntu
systems it may generate 4; in this case we have to discard
the extra events. On Debian/Ubuntu ev->key.keysym.mod
will always be zero, but for other systems we need the
complicated condition below. */
if ((ev->key.keysym.mod & KMOD_CAPS) ==
(ev->type == SDL_KEYDOWN ? KMOD_CAPS : 0)) {
kbd_put_keycode(keycode);
kbd_put_keycode(keycode | 0x80);
}
return;
case 0x45: /* num lock */
/* Same as above. */
if ((ev->key.keysym.mod & KMOD_NUM) ==
(ev->type == SDL_KEYDOWN ? KMOD_NUM : 0)) {
kbd_put_keycode(keycode);
kbd_put_keycode(keycode | 0x80);
}
return;
Now, the solution of the riddle. The patch was correctly submitted as
+ SDL_UseLockKeys = getenv ("SDL_DISABLE_LOCK_KEYS") == NULL;
...
+ use_lock_keys = SDL_UseLockKeys;
...
+ if (!use_lock_keys)
+ break;
(i.e. by default do not change anything) but the maintainer apparently
morphed it into
+ SDL_UseLockKeys = getenv("SDL_DISABLE_LOCK_KEYS");
...
+ use_lock_keys = ( SDL_UseLockKeys && *SDL_UseLockKeys );
...
+ if ( ! use_lock_keys )
+ break;
which changed the default and the meaning of SDL_DISABLE_LOCK_KEYS.
I initially thought about removing the caps lock/num lock hack
altogether and add the following, however it would need SDL 1.2.14
because SDL_NO_LOCK_KEYS support was added exactly two months after
1.2.13 was released. :-( :-(
/* There are two versions around of a Debian patch that changes the
way Caps Lock and Num Lock are handled. The first version
by default sends only one of the KeyDown/KeyUp events, unless
SDL_DISABLE_LOCK_KEYS is present in the environment. The second
version instead by default sends both events, unless
SDL_DISABLE_LOCK_KEYS is present and not empty. This version
is the most commonly found (and a totally braindead idea).
Upstream instead supports SDL_NO_LOCK_KEYS which, if set to 1,
will generate all four events---which is what we want. Luckily,
there is a combination of environment variable that will satisfy
all variant. */
putenv ("SDL_DISABLE_LOCK_KEYS", "");
putenv ("SDL_NO_LOCK_KEYS", "1");
Yes, I love Debian.
Paolo