The BIOS console's interpretation of LShift+RShift as equivalent to
AltGr requires the shifted ASCII characters to be present in the AltGr
mapping table, to allow AltGr-Shift-<key> to be interpreted in the
same way as AltGr-<key>.
For keyboard layouts that have different ASCII characters for
AltGr-<key> and AltGr-Shift-<key>, this will potentially leave the
character for AltGr-<key> inaccessible via the BIOS console if the
BIOS requires the use of the LShift+RShift workaround. This
theoretically affects the numeric keys in the Lithuanian ("lt")
keyboard layout (where the numerals are accessed via AltGr-<key> and
punctuation characters via AltGr-Shift-<key>), but the simple
workaround for that keyboard layout is to avoid using AltGr and Shift
entirely since the unmodified numeric keys are not remapped anyway.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The AltGr remapping table is constructed to include only keys that are
not reachable after applying the basic remapping table. The logic
currently fails to include keys that are omitted entirely from the
basic remapping table since they would map to a non-ASCII character.
Fix this logic by allowing the remapping tables to include null
mappings, which are then elided only at the point of constructing the
C code fragment.
Reported-by: Christian Nilsson <nikize@gmail.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Several keyboard layouts define ASCII characters as accessible only
via the AltGr modifier. Add support for this modifier to ensure that
all ASCII characters are accessible.
Experiments suggest that the BIOS console is likely to fail to
generate ASCII characters when the AltGr key is pressed. Work around
this limitation by accepting LShift+RShift (which will definitely
produce an ASCII character) as a synonym for AltGr.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Separate the concept of a keyboard mapping from a list of remapped
keys, to allow for the possibility of supporting multiple keyboard
mappings at runtime.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Rewrite genkeymap.pl in Python with added sanity checks, and update
the list of keyboard mappings to remove those no longer supported by
the underlying "loadkeys" tool.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The "us" keyboard layout contains a mapping for keycode 86 (which
seems not to correspond to any physical key on many US keyboards) to
the ASCII character '<'. This mapping causes conflicts with the
mapping for keycode 51, which also maps (with shift) to '<'.
Change the keyboard mapping generator to choose the lowest keycode for
each ASCII character as indicating the relevant mapping to use, on the
basis that a lower keycode roughly indicates a "more normal" key. On
a German keyboard, which has keys for both keycode 51 and keycode 86
present, this causes '<' to be remapped to ';', which is a closer
match to typical user expectations.
Reported-by: Sven Dreyer <sven@dreyer-net.de>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Inspired by LILO's keytab-lilo.pl, genkeymap.pl uses "loadkeys -b" to
obtain a Linux keyboard map, and generates a file keymap_xx.c in
hci/keymap.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
