LXR busybox/console-tools/dumpkmap.c

   1/* vi: set sw=4 ts=4: */
   2/*
   3 * Mini dumpkmap implementation for busybox
   4 *
   5 * Copyright (C) Arne Bernin <arne@matrix.loopback.org>
   6 *
   7 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
   8 */
   9//config:config DUMPKMAP
  10//config:       bool "dumpkmap (1.6 kb)"
  11//config:       default y
  12//config:       select PLATFORM_LINUX
  13//config:       help
  14//config:       This program dumps the kernel's keyboard translation table to
  15//config:       stdout, in binary format. You can then use loadkmap to load it.
  16
  17//applet:IF_DUMPKMAP(APPLET_NOEXEC(dumpkmap, dumpkmap, BB_DIR_BIN, BB_SUID_DROP, dumpkmap))
  18/* bb_common_bufsiz1 usage here is safe wrt NOEXEC: not expecting it to be zeroed. */
  19
  20//kbuild:lib-$(CONFIG_DUMPKMAP) += dumpkmap.o
  21
  22//usage:#define dumpkmap_trivial_usage
  23//usage:       "> keymap"
  24//usage:#define dumpkmap_full_usage "\n\n"
  25//usage:       "Print a binary keyboard translation table to stdout"
  26//usage:
  27//usage:#define dumpkmap_example_usage
  28//usage:       "$ dumpkmap > keymap\n"
  29
  30#include "libbb.h"
  31#include "common_bufsiz.h"
  32
  33/* From <linux/kd.h> */
  34struct kbentry {
  35        unsigned char kb_table;
  36        unsigned char kb_index;
  37        unsigned short kb_value;
  38};
  39#define KDGKBENT 0x4B46  /* gets one entry in translation table */
  40
  41/* From <linux/keyboard.h> */
  42#define NR_KEYS 128
  43#define MAX_NR_KEYMAPS 256
  44
  45int dumpkmap_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  46int dumpkmap_main(int argc UNUSED_PARAM, char **argv)
  47{
  48        struct kbentry ke;
  49        int i, j, fd;
  50
  51        /* When user accidentally runs "dumpkmap FILE"
  52         * instead of "dumpkmap >FILE", we'd dump binary stuff to tty.
  53         * Let's prevent it:
  54         */
  55        if (argv[1])
  56                bb_show_usage();
  57/*      bb_warn_ignoring_args(argv[1]);*/
  58
  59        fd = get_console_fd_or_die();
  60
  61#define flags bb_common_bufsiz1
  62        setup_common_bufsiz();
  63        /*                     0 1 2 3 4 5 6 7 8 9 a b c=12 */
  64        memcpy(flags, "bkeymap\1\1\1\0\1\1\1\0\1\1\1\0\1",
  65        /* Can use sizeof, or sizeof-1. sizeof is even, using that */
  66        /****/ sizeof("bkeymap\1\1\1\0\1\1\1\0\1\1\1\0\1")
  67        );
  68        write(STDOUT_FILENO, flags, 7 + MAX_NR_KEYMAPS);
  69#define flags7 (flags + 7)
  70
  71        for (i = 0; i < 13; i++) {
  72                if (flags7[i]) {
  73                        for (j = 0; j < NR_KEYS; j++) {
  74                                ke.kb_index = j;
  75                                ke.kb_table = i;
  76                                if (!ioctl_or_perror(fd, KDGKBENT, &ke,
  77                                                "ioctl(KDGKBENT{%d,%d}) failed",
  78                                                j, i)
  79                                ) {
  80                                        write(STDOUT_FILENO, &ke.kb_value, 2);
  81                                }
  82                        }
  83                }
  84        }
  85        if (ENABLE_FEATURE_CLEAN_UP) {
  86                close(fd);
  87        }
  88        return EXIT_SUCCESS;
  89}
  90