Creating a ``Magic Button''
Artem Ignatiev
timon at memphis.mephi.ru
Mon Feb 23 12:12:05 PST 2004
Hello, hackers
Friend of mine, who's using linux, showed me once this kind of things:
``When I'm too bored to do shutdown, I use Alt-SysRq button.
Sync-Sync-Sync, remount all fs to r/o, halt'' - or something like that.
I thought that this will be useful feature - when system is almost dead,
but syscons's still alive (and you have no debugger in kernel) try to
minimize loss of data trying to sync your disks, and doing halt.
Adding ``SYNC'' button to syscons & kbdcontrol went fine, but then I
wished to make an accented keys, with all these neat things. I've found
that kbdcontrol don't allows me to use dead keys for entering other,
than just plain ascii symbols. So I wished to change kbdcontrol a little
bit more, to allow entering keys like ``pdwn'' from accents. So - the
last thing to do is to change definition of accentmap_t like this:
--- /sys/sys/kbio.h Mon Feb 23 22:24:24 2004
+++ kbio.h Mon Feb 23 23:07:01 2004
@@ -179,13 +179,13 @@
#define F(x) ((x)+F_FN-1)
#define S(x) ((x)+F_SCR-1)
#define ACC(x) ((x)+F_ACC)
struct acc_t {
u_char accchar;
- u_char map[NUM_ACCENTCHARS][2];
+ u_short map[NUM_ACCENTCHARS][2];
};
struct accentmap {
u_short n_accs;
struct acc_t acc[NUM_DEADKEYS];
};
but immediately after applying this patch, PIO_DEADKEYMAP suddenly
disappeared (kbdcontrol gets ENOTTY "Inappopriate ioctl for device" when
trying to set accentmap).
I can't find out, what and where depends on acc_t. What am i missing?
Below is the patch of ``what i've done already'', it still lacks some
bits, like accurate dump of accents definitions.
-------------- next part --------------
--- ./sys/dev/kbd/kbd.c.orig Sun Jan 25 03:48:55 2004
+++ ./sys/dev/kbd/kbd.c Mon Feb 23 16:29:13 2004
@@ -1280,7 +1280,7 @@
/* NON-LOCKING KEYS */
case SPSC: case RBT: case SUSP: case STBY:
case DBG: case NEXT: case PREV: case PNC:
- case HALT: case PDWN:
+ case HALT: case PDWN: case SYNC:
*accents = 0;
break;
case BTAB:
--- ./sys/dev/syscons/syscons.c.orig Sun Jan 25 04:02:07 2004
+++ ./sys/dev/syscons/syscons.c Mon Feb 23 16:57:39 2004
@@ -50,6 +50,7 @@
#include <sys/reboot.h>
#include <sys/signalvar.h>
#include <sys/sysctl.h>
+#include <sys/sysproto.h>
#include <sys/tty.h>
#include <sys/power.h>
@@ -3355,6 +3356,10 @@
case PNC:
if (enable_panic_key)
panic("Forced by the panic key");
+ break;
+ case SYNC:
+ printf("Syncing disks\n");
+ sync(&thread0, NULL);
break;
case NEXT:
--- ./sys/sys/kbio.h.orig Sun Jan 25 03:55:12 2004
+++ ./sys/sys/kbio.h Mon Feb 23 22:24:24 2004
@@ -174,6 +174,7 @@
#define HALT 0xa1 /* halt machine */
#define PDWN 0xa2 /* halt machine and power down */
#define PASTE 0xa3 /* paste from cut-paste buffer */
+#define SYNC 0xa4 /* force sync filesystems */
#define F(x) ((x)+F_FN-1)
#define S(x) ((x)+F_SCR-1)
--- ./usr.sbin/kbdcontrol/lex.l.orig Sun Jan 25 04:15:46 2004
+++ ./usr.sbin/kbdcontrol/lex.l Sun Jan 25 04:16:01 2004
@@ -72,6 +72,7 @@
halt { return THALT; }
pdwn { return TPDWN; }
paste { return TPASTE; }
+sync { return TSYNC; }
NUL|nul { number = 0; return TNUM; }
SOH|soh { number = 1; return TNUM; }
--- ./usr.sbin/kbdcontrol/lex.h.orig Sun Jan 25 04:16:23 2004
+++ ./usr.sbin/kbdcontrol/lex.h Sun Jan 25 04:16:48 2004
@@ -64,6 +64,7 @@
#define THALT 289
#define TPDWN 290
#define TPASTE 291
+#define TSYNC 292
extern int number;
extern char letter;
--- ./usr.sbin/kbdcontrol/kbdcontrol.c.orig Sun Jan 25 04:17:01 2004
+++ ./usr.sbin/kbdcontrol/kbdcontrol.c Mon Feb 23 22:12:07 2004
@@ -238,6 +238,8 @@
return PDWN | 0x100;
case TPASTE:
return PASTE | 0x100;
+ case TSYNC:
+ return SYNC | 0x100;
case TACC:
if (ACC(number) > L_ACC)
return -1;
@@ -360,6 +362,39 @@
return -1;
}
switch ((token = yylex())) {
+ case TNEXT:
+ c2 = NEXT | SPCLKEY;
+ break;
+ case TPREV:
+ c2 = PREV | SPCLKEY;
+ break;
+ case TRBT:
+ c2 = RBT | SPCLKEY;
+ break;
+ case TDBG:
+ c2 = DBG | SPCLKEY;
+ break;
+ case TSUSP:
+ c2 = SUSP | SPCLKEY;
+ break;
+ case TSPSC:
+ c2 = SPSC | SPCLKEY;
+ break;
+ case TPANIC:
+ c2 = PNC | SPCLKEY;
+ break;
+ case THALT:
+ c2 = HALT | SPCLKEY;
+ break;
+ case TPDWN:
+ c2 = PDWN | SPCLKEY;
+ break;
+ case TPASTE:
+ c2 = PASTE | SPCLKEY;
+ break;
+ case TSYNC:
+ c2 = SYNC | SPCLKEY;
+ break;
case TLET:
c2 = letter;
break;
@@ -451,6 +486,9 @@
case PNC | 0x100:
fprintf(fp, " panic ");
break;
+ case SYNC | 0x100:
+ fprintf(fp, " sync ");
+ break;
case LSHA | 0x100:
fprintf(fp, " lshifta");
break;
--- share/syscons/keymaps/ru.koi8-r.kbd Mon Apr 9 20:36:48 2001
+++ /usr/share/syscons/keymaps/ru.koi8-r.timon.kbd Mon Feb 23 16:38:46 2004
@@ -4,7 +4,7 @@
# code base shift cntrl shift alt shift cntrl shift state
# ------------------------------------------------------------------
000 nop nop nop nop nop nop nop nop O
- 001 esc esc nop nop 155 155 debug nop O
+ 001 esc esc dogo nop 155 155 debug nop O
002 '1' '!' nop nop 177 161 nop nop O
003 '2' '@' nul nul 178 192 128 128 O
004 '3' '#' nop nop 179 163 nop nop O
@@ -132,7 +132,7 @@
126 nop nop nop nop nop nop nop nop O
127 nop nop nop nop nop nop nop nop O
128 nop nop nop nop nop nop nop nop O
- 129 esc esc nop nop 155 155 debug nop O
+ 129 esc esc dogo nop 155 155 debug nop O
130 '!' '1' nop nop 177 161 nop nop O
131 '"' '2' nul nul 178 192 128 128 O
132 ''' '3' nop nop 179 163 nop nop O
@@ -240,3 +240,5 @@
234 fkey63 fkey63 fkey63 fkey63 fkey63 fkey63 fkey63 fkey63 O
235 fkey64 fkey64 fkey64 fkey64 fkey64 fkey64 fkey64 fkey64 O
236 nop nop nop nop nop nop nop nop O
+dogo 001 ( 'd' debug ) ( 'h' halt ) ( 'p' pdwn ) ( 's' sync ) ( 'P' panic )
+#dogo 001 ( 'd' 32) ( 'h' 33) ('p' 34) ( 's' 35) ('P' 36)
More information about the freebsd-hackers
mailing list