ref: 94916808dd9a53ac297ab537851791894b919828
dir: /sys/src/cmd/aux/reboot.c/
#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); } }