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#include <u.h>
#include <libc.h>
void
reboot(void)
{
int fd;
fd = open("/dev/reboot", OWRITE);
if(fd >= 0)
write(fd, "reboot", 6);
exits(0);
}
char*
readenv(char *name, char *buf, int n)
{
char *ans;
int f;
char ename[200];
ans = buf;
ename[0] = 0;
strcat(ename, "/env/");
strcat(ename, name);
f = open(ename, OREAD);
if(f < 0)
return 0;
n = read(f, ans, n-1);
if(n < 0)
ans = 0;
else
ans[n] = 0;
close(f);
return ans;
}
int alarmed;
void
ding(void*, char*msg)
{
if(strstr(msg, "alarm")){
alarmed = 1;
noted(NCONT);
}
noted(NDFLT);
}
void
main(int argc, char **argv)
{
int fd;
char buf[256];
char file[128];
char *p;
Dir *d;
if(argc > 1)
strecpy(file, file+sizeof file, argv[1]);
else{
p = readenv("cputype", buf, sizeof buf);
if(p == 0)
exits(0);
file[0] = 0;
strcat(file, "/");
strcat(file, p);
strcat(file, "/lib");
}
if (access(file, AREAD) < 0)
sysfatal("%s not readable: %r", file);
switch(rfork(RFPROC|RFNOWAIT|RFNOTEG|RFCFDG)){
case 0:
break;
default:
exits(0);
}
notify(ding);
fd = open(file, OREAD);
if (fd < 0)
exits("no file");
// the logic here is to make a request every 5 minutes.
// If the request alarms out, that's OK, the file server
// may just be busy. If the request fails for any other
// reason, it's probably because the connection went
// away so reboot.
for(;;){
alarm(1000*60);
alarmed = 0;
d = dirfstat(fd);
free(d);
if(d == nil)
if(!alarmed)
reboot();
alarm(0);
sleep(60*1000*5);
}
}
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