console-tools/setkeycodes.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * setkeycodes
   4  *
   5  * Copyright (C) 1994-1998 Andries E. Brouwer <aeb@cwi.nl>
   6  *
   7  * Adjusted for BusyBox by Erik Andersen <andersen@codepoet.org>
   8  *
   9  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  10  */
  11 //config:config SETKEYCODES
  12 //config:       bool "setkeycodes (2.4 kb)"
  13 //config:       default y
  14 //config:       help
  15 //config:       This program loads entries into the kernel's scancode-to-keycode
  16 //config:       map, allowing unusual keyboards to generate usable keycodes.
  17
  18 //applet:IF_SETKEYCODES(APPLET_NOEXEC(setkeycodes, setkeycodes, BB_DIR_USR_BIN, BB_SUID_DROP, setkeycodes))
  19
  20 //kbuild:lib-$(CONFIG_SETKEYCODES) += setkeycodes.o
  21
  22 //usage:#define setkeycodes_trivial_usage
  23 //usage:       "{ SCANCODE KEYCODE }..."
  24 //usage:#define setkeycodes_full_usage "\n\n"
  25 //usage:       "Modify kernel's scancode-to-keycode map,\n"
  26 //usage:       "allowing unusual keyboards to generate usable keycodes.\n\n"
  27 //usage:       "SCANCODE is either xx or e0xx (hexadecimal), KEYCODE is decimal."
  28 //usage:
  29 //usage:#define setkeycodes_example_usage
  30 //usage:       "$ setkeycodes e030 127\n"
  31
  32 #include "libbb.h"
  33
  34 /* From <linux/kd.h> */
  35 struct kbkeycode {
  36         unsigned scancode, keycode;
  37 };
  38 enum {
  39         KDSETKEYCODE = 0x4B4D  /* write kernel keycode table entry */
  40 };
  41
  42 int setkeycodes_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  43 int setkeycodes_main(int argc, char **argv)
  44 {
  45         int fd;
  46
  47         if (!(argc & 1) /* if even */ || argc < 2) {
  48                 bb_show_usage();
  49         }
  50
  51         fd = get_console_fd_or_die();
  52
  53         while (argv[1]) {
  54                 struct kbkeycode a;
  55                 int sc;
  56
  57                 sc = xstrtoul_range(argv[1], 16, 0, 0xe07f);
  58                 if (sc >= 0xe000) {
  59                         sc -= 0xe000;
  60                         sc += 0x0080;
  61                 }
  62                 a.scancode = sc;
  63                 a.keycode = xatou_range(argv[2], 0, 255);
  64                 ioctl_or_perror_and_die(fd, KDSETKEYCODE, &a,
  65                         "can't set SCANCODE %x to KEYCODE %d",
  66                         sc, a.keycode);
  67                 argv += 2;
  68         }
  69         return EXIT_SUCCESS;
  70 }