busybox/console-tools/showkey.c
Denys Vlasenko cc131534e2 showkey: code shrink
function                                             old     new   delta
signal_handler                                        52      45      -7
showkey_main                                         461     454      -7
xset1                                                 40      29     -11

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2010-08-29 05:00:40 +02:00

139 lines
3.1 KiB
C

/* vi: set sw=4 ts=4: */
/*
* shows keys pressed. inspired by kbd package
*
* Copyright (C) 2008 by Vladimir Dronnikov <dronnikov@gmail.com>
*
* Licensed under GPLv2, see file LICENSE in this source tree.
*/
#include "libbb.h"
#include <linux/kd.h>
// set raw tty mode
// also used by microcom
// libbb candidates?
static void xget1(struct termios *t, struct termios *oldt)
{
tcgetattr(STDIN_FILENO, oldt);
*t = *oldt;
cfmakeraw(t);
}
static void xset1(struct termios *tio)
{
int ret = tcsetattr(STDIN_FILENO, TCSAFLUSH, tio);
if (ret) {
bb_perror_msg("can't tcsetattr for stdin");
}
}
/*
* GLOBALS
*/
struct globals {
int kbmode;
struct termios tio, tio0;
};
#define G (*ptr_to_globals)
#define kbmode (G.kbmode)
#define tio (G.tio)
#define tio0 (G.tio0)
#define INIT_G() do { \
SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
} while (0)
static void signal_handler(int signo)
{
// restore keyboard and console settings
xset1(&tio0);
xioctl(STDIN_FILENO, KDSKBMODE, (void *)(ptrdiff_t)kbmode);
// alarmed? -> exit 0
exit(SIGALRM == signo);
}
int showkey_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int showkey_main(int argc UNUSED_PARAM, char **argv)
{
enum {
OPT_a = (1<<0), // display the decimal/octal/hex values of the keys
OPT_k = (1<<1), // display only the interpreted keycodes (default)
OPT_s = (1<<2), // display only the raw scan-codes
};
// FIXME: aks are all mutually exclusive
getopt32(argv, "aks");
INIT_G();
// get keyboard settings
xioctl(STDIN_FILENO, KDGKBMODE, &kbmode);
printf("kb mode was %s\n\nPress any keys. Program terminates %s\n\n",
kbmode == K_RAW ? "RAW" :
(kbmode == K_XLATE ? "XLATE" :
(kbmode == K_MEDIUMRAW ? "MEDIUMRAW" :
(kbmode == K_UNICODE ? "UNICODE" : "?UNKNOWN?")))
, (option_mask32 & OPT_a) ? "when CTRL+D pressed" : "10s after last keypress"
);
// prepare for raw mode
xget1(&tio, &tio0);
// put stdin in raw mode
xset1(&tio);
if (option_mask32 & OPT_a) {
unsigned char c;
// just read stdin char by char
while (1 == safe_read(STDIN_FILENO, &c, 1)) {
printf("%3u 0%03o 0x%02x\r\n", c, c, c);
if (04 /*CTRL-D*/ == c)
break;
}
} else {
// we should exit on any signal
bb_signals(BB_FATAL_SIGS, signal_handler);
// set raw keyboard mode
xioctl(STDIN_FILENO, KDSKBMODE, (void *)(ptrdiff_t)((option_mask32 & OPT_k) ? K_MEDIUMRAW : K_RAW));
// read and show scancodes
while (1) {
char buf[18];
int i, n;
// setup 10s watchdog
alarm(10);
// read scancodes
n = read(STDIN_FILENO, buf, sizeof(buf));
i = 0;
while (i < n) {
char c = buf[i];
// show raw scancodes ordered? ->
if (option_mask32 & OPT_s) {
printf("0x%02x ", buf[i++]);
// show interpreted scancodes (default) ? ->
} else {
int kc;
if (i+2 < n
&& (c & 0x7f) == 0
&& (buf[i+1] & 0x80) != 0
&& (buf[i+2] & 0x80) != 0
) {
kc = ((buf[i+1] & 0x7f) << 7) | (buf[i+2] & 0x7f);
i += 3;
} else {
kc = (c & 0x7f);
i++;
}
printf("keycode %3u %s", kc, (c & 0x80) ? "release" : "press");
}
}
puts("\r");
}
}
// cleanup
signal_handler(SIGALRM);
// should never be here!
return EXIT_SUCCESS;
}