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  */
  10 /* no options, no getopt */
  11
  12 //usage:#define dumpkmap_trivial_usage
  13 //usage:       "> keymap"
  14 //usage:#define dumpkmap_full_usage "\n\n"
  15 //usage:       "Print a binary keyboard translation table to stdout"
  16 //usage:
  17 //usage:#define dumpkmap_example_usage
  18 //usage:       "$ dumpkmap > keymap\n"
  19
  20 #include "libbb.h"
  21
  22 /* From <linux/kd.h> */
  23 struct kbentry {
  24         unsigned char kb_table;
  25         unsigned char kb_index;
  26         unsigned short kb_value;
  27 };
  28 #define KDGKBENT 0x4B46  /* gets one entry in translation table */
  29
  30 /* From <linux/keyboard.h> */
  31 #define NR_KEYS 128
  32 #define MAX_NR_KEYMAPS 256
  33
  34 int dumpkmap_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  35 int dumpkmap_main(int argc UNUSED_PARAM, char **argv)
  36 {
  37         struct kbentry ke;
  38         int i, j, fd;
  39         RESERVE_CONFIG_BUFFER(flags, MAX_NR_KEYMAPS);
  40
  41         /* When user accidentally runs "dumpkmap FILE"
  42          * instead of "dumpkmap >FILE", we'd dump binary stuff to tty.
  43          * Let's prevent it: */
  44         if (argv[1])
  45                 bb_show_usage();
  46 /*      bb_warn_ignoring_args(argv[1]);*/
  47
  48         fd = get_console_fd_or_die();
  49
  50         write(STDOUT_FILENO, "bkeymap", 7);
  51
  52         /* Here we want to set everything to 0 except for indexes:
  53          * [0-2] [4-6] [8-10] [12] */
  54         memset(flags, 0x00, MAX_NR_KEYMAPS);
  55         memset(flags, 0x01, 13);
  56         flags[3] = flags[7] = flags[11] = 0;
  57
  58         /* dump flags */
  59         write(STDOUT_FILENO, flags, MAX_NR_KEYMAPS);
  60
  61         for (i = 0; i < MAX_NR_KEYMAPS; i++) {
  62                 if (flags[i] == 1) {
  63                         for (j = 0; j < NR_KEYS; j++) {
  64                                 ke.kb_index = j;
  65                                 ke.kb_table = i;
  66                                 if (!ioctl_or_perror(fd, KDGKBENT, &ke,
  67                                                 "ioctl failed with %s, %s, %p",
  68                                                 (char *)&ke.kb_index,
  69                                                 (char *)&ke.kb_table,
  70                                                 &ke.kb_value)
  71                                 ) {
  72                                         write(STDOUT_FILENO, (void*)&ke.kb_value, 2);
  73                                 }
  74                         }
  75                 }
  76         }
  77         if (ENABLE_FEATURE_CLEAN_UP) {
  78                 close(fd);
  79                 RELEASE_CONFIG_BUFFER(flags);
  80         }
  81         return EXIT_SUCCESS;
  82 }