rockbox/apps/plugins/lua/include_lua/create_kbd_layout.lua
William Wilgus adff45ca21 lua -- temp loader
fix a few bugs, improve memory usage

Change-Id: I6ceefd033000a6178eab0dd513679b5d72cec81c
2021-05-06 21:36:55 -04:00

107 lines
3.6 KiB
Lua

--[[
/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2021 William Wilgus
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
]]
--create keyboard layout
--BILGUS 4/2021
-- create_kbd_layout = require("create_kbd_layout")
-- local layout = create_kbd_layout("abcd")
local function encode_short(n)
return string.char(bit.band(0x00FF, n), bit.rshift(bit.band(0xFF00, n), 8))
end
local function utf8decode(str)
local INVALID = 0xfffd
local t = {}
local function check_char(c)
local tail = false
local code
c = string.byte(c)
if (c <= 0x7f) or (c >= 0xc2) then
-- Start of new character
if (c < 0x80) then -- U-00000000 - U-0000007F, 1 string.byte
code = c;
elseif (c < 0xe0) then -- U-00000080 - U-000007FF, 2 string.bytes
tail = 1;
code = bit.band(c, 0x1f)
elseif (c < 0xf0) then -- U-00000800 - U-0000FFFF, 3 string.bytes
tail = 2;
code = bit.band(c, 0x0f)
elseif (c < 0xf5) then -- U-00010000 - U-001FFFFF, 4 string.bytes
tail = 3;
code = bit.band(c, 0x07)
else
-- Invalid size
code = INVALID;
end
while tail and c ~= 0 do
tail = tail - 1
if bit.band(c, 0xc0) == 0x80 then
-- Valid continuation character
code = bit.bor(bit.lshift(code, 6),bit.band(c, 0x3f))
else
-- Invalid continuation char
code = INVALID;
break;
end
end
else
-- Invalid UTF-8 char
code = INVALID;
end
-- currently we don't support chars above U-FFFF
t[#t + 1 ] = encode_short((code < 0x10000) and code or INVALID)
end
str:gsub(".", check_char) -- run check function for every char
return table.concat(t)
end
local function create_keyboard_layout(s_layout)
local insert = table.insert
lines = {}
for str in string.gmatch(s_layout, "([^\n]+)") do
local len = string.len(str)
lines[#lines + 1] =
table.concat({encode_short(len), utf8decode(str)})
end
lines[#lines + 1] = encode_short(0xFEFF)
return table.concat(lines)
end
--[[
local name = "Test_KBD_LAYOUT_" .. tostring(1)
local test = create_keyboard_layout("ABCDEFGHIJKLM\nNOPQRSTUVWXYZ\n0123456789")
local file = io.open('/' .. name, "w+") -- overwrite, rb ignores the 'b' flag
file:write(test)-- write the layout to the file now
file:close()
if not file then
rb.splash(rb.HZ, "Error opening /" .. name)
return
end
rb.kbd_input(name, test)
]]
return create_keyboard_layout