157 lines
2.1 KiB
C
157 lines
2.1 KiB
C
/*
|
|
* watchdog framework
|
|
*/
|
|
#include "u.h"
|
|
#include "../port/lib.h"
|
|
#include "mem.h"
|
|
#include "dat.h"
|
|
#include "fns.h"
|
|
#include "io.h"
|
|
#include "../port/error.h"
|
|
|
|
enum {
|
|
Qdir,
|
|
Qwdctl,
|
|
};
|
|
|
|
static Watchdog *wd;
|
|
static Dirtab wddir[] = {
|
|
".", { Qdir, 0, QTDIR }, 0, 0550,
|
|
"wdctl", { Qwdctl, 0 }, 0, 0660,
|
|
};
|
|
|
|
|
|
void
|
|
addwatchdog(Watchdog *watchdog)
|
|
{
|
|
if(wd){
|
|
print("addwatchdog: watchdog already installed\n");
|
|
return;
|
|
}
|
|
wd = watchdog;
|
|
if(wd)
|
|
wd->disable();
|
|
}
|
|
|
|
static Chan*
|
|
wdattach(char *spec)
|
|
{
|
|
return devattach('w', spec);
|
|
}
|
|
|
|
static Walkqid*
|
|
wdwalk(Chan *c, Chan *nc, char **name, int nname)
|
|
{
|
|
return devwalk(c, nc, name, nname, wddir, nelem(wddir), devgen);
|
|
}
|
|
|
|
static int
|
|
wdstat(Chan *c, uchar *dp, int n)
|
|
{
|
|
return devstat(c, dp, n, wddir, nelem(wddir), devgen);
|
|
}
|
|
|
|
static Chan*
|
|
wdopen(Chan* c, int omode)
|
|
{
|
|
return devopen(c, omode, wddir, nelem(wddir), devgen);
|
|
}
|
|
|
|
static void
|
|
wdclose(Chan*)
|
|
{
|
|
}
|
|
|
|
static long
|
|
wdread(Chan* c, void* a, long n, vlong off)
|
|
{
|
|
ulong offset = off;
|
|
char *p;
|
|
|
|
switch((ulong)c->qid.path){
|
|
case Qdir:
|
|
return devdirread(c, a, n, wddir, nelem(wddir), devgen);
|
|
|
|
case Qwdctl:
|
|
if(wd == nil || wd->stat == nil)
|
|
return 0;
|
|
|
|
p = smalloc(READSTR);
|
|
if(waserror()){
|
|
free(p);
|
|
nexterror();
|
|
}
|
|
|
|
wd->stat(p, p + READSTR);
|
|
n = readstr(offset, a, n, p);
|
|
free(p);
|
|
poperror();
|
|
return n;
|
|
|
|
default:
|
|
error(Egreg);
|
|
break;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static long
|
|
wdwrite(Chan* c, void* a, long n, vlong off)
|
|
{
|
|
ulong offset = off;
|
|
char *p;
|
|
|
|
switch((ulong)c->qid.path){
|
|
case Qdir:
|
|
error(Eperm);
|
|
|
|
case Qwdctl:
|
|
if(wd == nil)
|
|
return n;
|
|
|
|
if(offset || n >= READSTR)
|
|
error(Ebadarg);
|
|
|
|
if((p = strchr(a, '\n')) != nil)
|
|
*p = 0;
|
|
|
|
if(strncmp(a, "enable", n) == 0)
|
|
wd->enable();
|
|
else if(strncmp(a, "disable", n) == 0)
|
|
wd->disable();
|
|
else if(strncmp(a, "restart", n) == 0)
|
|
wd->restart();
|
|
else
|
|
error(Ebadarg);
|
|
return n;
|
|
|
|
default:
|
|
error(Egreg);
|
|
break;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
Dev wddevtab = {
|
|
'w',
|
|
"watchdog",
|
|
|
|
devreset,
|
|
devinit,
|
|
devshutdown,
|
|
wdattach,
|
|
wdwalk,
|
|
wdstat,
|
|
wdopen,
|
|
devcreate,
|
|
wdclose,
|
|
wdread,
|
|
devbread,
|
|
wdwrite,
|
|
devbwrite,
|
|
devremove,
|
|
devwstat,
|
|
devpower,
|
|
};
|