busybox/console-tools/dumpkmap.c
Denys Vlasenko b9be780705 sv,svc: fix NOEXEC fallout
function                                             old     new   delta
svc_main                                             145     162     +17
sv                                                  1280    1297     +17
status                                               139     133      -6
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/1 up/down: 34/-6)              Total: 28 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-08-06 21:23:03 +02:00

91 lines
2.4 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Mini dumpkmap implementation for busybox
*
* Copyright (C) Arne Bernin <arne@matrix.loopback.org>
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*
*/
//config:config DUMPKMAP
//config: bool "dumpkmap (1.3 kb)"
//config: default y
//config: select PLATFORM_LINUX
//config: help
//config: This program dumps the kernel's keyboard translation table to
//config: stdout, in binary format. You can then use loadkmap to load it.
//applet:IF_DUMPKMAP(APPLET_NOEXEC(dumpkmap, dumpkmap, BB_DIR_BIN, BB_SUID_DROP, dumpkmap))
/* bb_common_bufsiz1 usage here is safe wrt NOEXEC: not expecting it to be zeroed. */
//kbuild:lib-$(CONFIG_DUMPKMAP) += dumpkmap.o
//usage:#define dumpkmap_trivial_usage
//usage: "> keymap"
//usage:#define dumpkmap_full_usage "\n\n"
//usage: "Print a binary keyboard translation table to stdout"
//usage:
//usage:#define dumpkmap_example_usage
//usage: "$ dumpkmap > keymap\n"
#include "libbb.h"
#include "common_bufsiz.h"
/* From <linux/kd.h> */
struct kbentry {
unsigned char kb_table;
unsigned char kb_index;
unsigned short kb_value;
};
#define KDGKBENT 0x4B46 /* gets one entry in translation table */
/* From <linux/keyboard.h> */
#define NR_KEYS 128
#define MAX_NR_KEYMAPS 256
int dumpkmap_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int dumpkmap_main(int argc UNUSED_PARAM, char **argv)
{
struct kbentry ke;
int i, j, fd;
/* When user accidentally runs "dumpkmap FILE"
* instead of "dumpkmap >FILE", we'd dump binary stuff to tty.
* Let's prevent it:
*/
if (argv[1])
bb_show_usage();
/* bb_warn_ignoring_args(argv[1]);*/
fd = get_console_fd_or_die();
#define flags bb_common_bufsiz1
setup_common_bufsiz();
/* 0 1 2 3 4 5 6 7 8 9 a b c=12 */
memcpy(flags, "bkeymap\1\1\1\0\1\1\1\0\1\1\1\0\1",
/* Can use sizeof, or sizeof-1. sizeof is even, using that */
/****/ sizeof("bkeymap\1\1\1\0\1\1\1\0\1\1\1\0\1")
);
write(STDOUT_FILENO, flags, 7 + MAX_NR_KEYMAPS);
#define flags7 (flags + 7)
for (i = 0; i < 13; i++) {
if (flags7[i]) {
for (j = 0; j < NR_KEYS; j++) {
ke.kb_index = j;
ke.kb_table = i;
if (!ioctl_or_perror(fd, KDGKBENT, &ke,
"ioctl(KDGKBENT{%d,%d}) failed",
j, i)
) {
write(STDOUT_FILENO, &ke.kb_value, 2);
}
}
}
}
if (ENABLE_FEATURE_CLEAN_UP) {
close(fd);
}
return EXIT_SUCCESS;
}