[patch] Reset sysload if sysctl call failed in usr.bin/top/machine.c

[Nan Xiao]

Hi tech@,

Below is the patch of resetting sysload if sysctl call failed in
usr.bin/top/machine.c, otherwise the memory of sysload is undetermined.
(The same process as uvmexp and bcstats).

Index: machine.c
===================================================================
RCS file: /cvs/src/usr.bin/top/machine.c,v
retrieving revision 1.90
diff -u -p -r1.90 machine.c
--- machine.c   14 May 2018 12:31:21 -0000      1.90
+++ machine.c   22 May 2018 09:49:39 -0000
@@ -282,8 +282,10 @@ get_system_info(struct system_info *si)
        }

        size = sizeof(sysload);
-       if (sysctl(sysload_mib, 2, &sysload, &size, NULL, 0) < 0)
+       if (sysctl(sysload_mib, 2, &sysload, &size, NULL, 0) < 0) {
                warn("sysctl failed");
+               bzero(&sysload, sizeof(sysload));
+       }
        infoloadp = si->load_avg;
        for (i = 0; i < 3; i++)
                *infoloadp++ = ((double) sysload.ldavg[i]) / sysload.fscale;

-- 
Best Regards
Nan Xiao