hush/console-tools/loadkmap.c
Denys Vlasenko 054f3eb784 loadkmap: explain what happens with K_ALLOCATED key value
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2013-09-19 17:56:59 +02:00

92 lines
2.4 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Mini loadkmap implementation for busybox
*
* Copyright (C) 1998 Enrique Zanardi <ezanardi@ull.es>
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
//usage:#define loadkmap_trivial_usage
//usage: "< keymap"
//usage:#define loadkmap_full_usage "\n\n"
//usage: "Load a binary keyboard translation table from stdin\n"
/* //usage: "\n -C TTY Affect TTY instead of /dev/tty" */
//usage:
//usage:#define loadkmap_example_usage
//usage: "$ loadkmap < /etc/i18n/lang-keymap\n"
#include "libbb.h"
#define BINARY_KEYMAP_MAGIC "bkeymap"
/* From <linux/kd.h> */
struct kbentry {
unsigned char kb_table;
unsigned char kb_index;
unsigned short kb_value;
};
/* sets one entry in translation table */
#define KDSKBENT 0x4B47
/* From <linux/keyboard.h> */
#define NR_KEYS 128
#define MAX_NR_KEYMAPS 256
int loadkmap_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int loadkmap_main(int argc UNUSED_PARAM, char **argv)
{
struct kbentry ke;
int i, j, fd;
uint16_t ibuff[NR_KEYS];
/* const char *tty_name = CURRENT_TTY; */
RESERVE_CONFIG_BUFFER(flags, MAX_NR_KEYMAPS);
/* When user accidentally runs "loadkmap FILE"
* instead of "loadkmap <FILE", we end up waiting for input from tty.
* Let's prevent it: */
if (argv[1])
bb_show_usage();
/* bb_warn_ignoring_args(argv[1]); */
fd = get_console_fd_or_die();
/* or maybe:
opt = getopt32(argv, "C:", &tty_name);
fd = xopen_nonblocking(tty_name);
*/
xread(STDIN_FILENO, flags, 7);
if (strncmp(flags, BINARY_KEYMAP_MAGIC, 7))
bb_error_msg_and_die("not a valid binary keymap");
xread(STDIN_FILENO, flags, MAX_NR_KEYMAPS);
for (i = 0; i < MAX_NR_KEYMAPS; i++) {
if (flags[i] != 1)
continue;
xread(STDIN_FILENO, ibuff, NR_KEYS * sizeof(uint16_t));
for (j = 0; j < NR_KEYS; j++) {
ke.kb_index = j;
ke.kb_table = i;
ke.kb_value = ibuff[j];
/*
* Note: table[idx:0] can contain special value
* K_ALLOCATED (marks allocated tables in kernel).
* dumpkmap saves the value as-is; but attempts
* to load it here fail, since it isn't a valid
* key value: it is K(KT_SPEC,126) == 2<<8 + 126,
* whereas last valid KT_SPEC is
* K_BARENUMLOCK == K(KT_SPEC,19).
* So far we just ignore these errors:
*/
ioctl(fd, KDSKBENT, &ke);
}
}
if (ENABLE_FEATURE_CLEAN_UP) {
close(fd);
RELEASE_CONFIG_BUFFER(flags);
}
return EXIT_SUCCESS;
}