added uname check in ck_boottime(); updated variable names in merge_meas();

1 files changed, 36 insertions, 23 deletions

diff --git a/ckt0.awk b/ckt0.awk
index ebe724f..0c392a5 100644
--- a/ckt0.awk
+++ b/ckt0.awk
@@ -1,28 +1,24 @@
 #!/usr/bin/env awk -f
 
 
-function log10(n) {
+function log10(n) { return log(n)/log(10.0) }
 
-    return log(n)/log(10.0)
 
-}
-
-
-function merge_meas(val_est, unc_est, val_meas, unc_meas) {
+function merge_meas(est_val, est_unc, meas_val, meas_unc) {
 
     # Kalman filtering compares variances,
-    # convert uncerainties to square units
-    unc_est = (0.5*unc_est)^2.0
-    unc_meas = (0.5*unc_meas)^2.0
+    # convert uncertainties to square units
+    est_unc = (0.5*est_unc)^2.0
+    meas_unc = (0.5*meas_unc)^2.0
 
-    G_K = (unc_est)/((unc_est) + (unc_meas))
-    val_est = val_est + G_K*(val_meas - val_est)
-    unc_est = (unc_est*unc_meas)/(unc_est + unc_meas)
+    K = (est_unc)/((est_unc) + (meas_unc))
+    est_val = est_val + K*(meas_val - est_val)
+    est_unc = (est_unc*meas_unc)/(est_unc + meas_unc)
 
-    # convert unc_est back to original units
-    unc_est = 2.0*sqrt(unc_est)
+    # convert est_unc back to original units
+    est_unc = 2.0*sqrt(est_unc)
 
-    return sprintf(OFMT OFS OFMT ORS, val_est, unc_est)
+    return sprintf(OFMT OFS OFMT ORS, est_val, est_unc)
 
 }
 
@@ -44,21 +40,41 @@ function sigfig(val, unc) {
 }
 
 
+function ck_boottime() {
+
+    "uname" | getline uname
+    close("uname")
+
+    if (uname ~/OpenBSD/) {
+        "sysctl kern.boottime" | getline t0_k
+        close("sysctl kern.boottime")
+        sub("^.*=", "", t0_k)
+        split(t0_k, t0_k_arr)
+        t0_k_arr[2] = (index("JanFebMarAprMayJunJulAugSepOctNovDec", t0_k_arr[2]) + 2)/3.0
+        gsub(":", " ", t0_k_arr[4])
+        t0_k = sprintf("%04d %02d %02d %s", t0_k_arr[5], t0_k_arr[2], t0_k_arr[3], t0_k_arr[4])
+        t0_k = mktime(t0_k)
+    }
+
+    return t0_k
+
+}
+
+
 # function ck_boottime() {
-# 
 #     "sysctl kern.boottime" | getline t_kboot
 #     close("sysctl kern.boottime")
 #     sub("^.*\{", "", t_kboot)
 #     sub("\}.*$", "", t_kboot)
 #     split(t_kboot, t_kboot_arr, ",")
-# 
+#
 #     for (i in t_kboot_arr) {
 #         sub("^.*= ", "", t_kboot_arr[i])
 #     }
-# 
+#
 #     t_kboot = sprintf(t_kboot_arr[1] "." t_kboot_arr[2])
 #     return t_kboot
-# 
+#
 # }
 
 
@@ -141,15 +157,12 @@ BEGIN {
 
     # check ARGV for previous estimate
     if (ARGC > 0) {
-        ARGV[1] ? t0_est[1] = ARGV[1] : t0_est[1] = 0.0
+        ARGV[1] ? t0_est[1] = ARGV[1] : t0_est[1] = ck_boottime()
         ARGV[2] ? t0_est[2] = ARGV[2] : t0_est[2] = systime()
     }
     #print("t0_est = ", t0_est[1])
     #print("t_boot_unc = ", t0_est[2])
 
-    # wait (sleep) based on uncertainty
-    # print(60.0/t0_est[2])
-
     # check uptime, update estimate
     print(ck_uptime(t0_est[1], t0_est[2]))