From fb4a95730d8a244f42c501d2b10b1a06b13d340b Mon Sep 17 00:00:00 2001
From: Lars Kruse <devel@sumpfralle.de>
Date: Fri, 11 Nov 2016 00:29:45 +0100
Subject: [PATCH] [chrony] simplify field handling

---
 plugins/time/chrony | 72 +++++++++++++++++++++++++++++++++------------
 1 file changed, 54 insertions(+), 18 deletions(-)

diff --git a/plugins/time/chrony b/plugins/time/chrony
index e10ddd3e..314860f6 100755
--- a/plugins/time/chrony
+++ b/plugins/time/chrony
@@ -37,19 +37,52 @@ Revision 0.3 2014/02/16 zjttoefs
   detect slow/fast time or freqency and adjust sign of value accordingly
   remove commented out code
 
+Revision 0.4 2016/11/10 Lars Kruse
+
+  rewrite field handling
+  use "which" for "chronyc" location
+  switch from "bash" to "sh"
+  fix exit code of failing "autoconf"
+
 =head1 AUTHOR
 
   joti
   zjttoefs
+  Lars Kruse <devel@sumpfralle.de>
 
 =cut
 
 CHRONYC="$(which chronyc | head -1)"
 
-# Frequency has extremely higher values than other. Therefore they are fitted by scaling. Adjust the factors here
-fieldfactors="1 1000 1 100 100 1000 1000"
-fields="stratum systime frequency residualfreq skew rootdelay rootdispersion"
-fieldnames="Stratum (=System Time (seconds,x=Frequency (ppm,x=Residual Freq (ppm,x=Skew (ppm,x=Root delay(seconds,x=Root dispersion (seconds,x"
+# Frequency has extremely higher values than other. Therefore they are fitted by scaling via suitable factors.
+# field definitions:
+#   - munin fieldname
+#   - factor for graph visualization (all values are supposed to reach a similar dimension)
+#   - regular expression of the chrony output line (may not contain whitespace, case insensitive)
+#   - label (may include "%d" for including the factor; may contain whitespace)
+fields="stratum		1	^Stratum		Stratum
+	systime		1000	^System.time		System Time (x%d)
+	frequency	1	^Frequency		Frequency (ppm)
+	residualfreq	100	^Residual.freq		Residual Freq (ppm, x%d)
+	skew		100	^Skew			Skew (ppm, x%d)
+	rootdelay	1000	^Root.delay		Root delay (seconds, x%d)
+	rootdispersion	1000	^Root.dispersion	Root dispersion (seconds, x%d)"
+
+# chrony example output (v2.4.1):
+#   Reference ID    : 131.188.3.221 (ntp1.rrze.uni-erlangen.de)
+#   Stratum         : 2
+#   Ref time (UTC)  : Thu Nov 10 22:39:50 2016
+#   System time     : 0.000503798 seconds slow of NTP time
+#   Last offset     : +0.000254355 seconds
+#   RMS offset      : 0.002186779 seconds
+#   Frequency       : 17.716 ppm slow
+#   Residual freq   : +0.066 ppm
+#   Skew            : 4.035 ppm
+#   Root delay      : 0.042980 seconds
+#   Root dispersion : 0.005391 seconds
+#   Update interval : 258.4 seconds
+#   Leap status     : Normal
+
 
 if [ "$1" = "autoconf" ]; then
 	if [ -n "$CHRONYC" ] && [ -x "$CHRONYC" ]; then
@@ -63,21 +96,24 @@ fi
 if [ "$1" = "config" ]; then
 	echo 'graph_title Chrony Tracking Stats'
 	echo 'graph_args --base 1000 -l 0'
-	echo 'units (seconds,ppm)'
+	echo 'graph_vlabel (seconds,ppm)'
 	echo 'graph_category time'
-		i=0
-		for a in $fields ; do
-			i=$((i + 1))
-			word="$(echo "$fieldnames" | cut -f "$i" -d '=')"
-			factor="$(echo "$fieldfactors" | cut -f "$i" -d ' ')"
-			echo "$a.label $word$factor)";
-			echo "$a.type GAUGE"
-		done
+	echo "$fields" | while read fieldname factor regex label; do
+		# insert the factor, if "%d" is part of the label
+		printf "${fieldname}.label $label\n" "$factor"
+		echo "${fieldname}.type GAUGE"
+	done
 	exit 0
 fi
 
-# remove non-needed output lines, remove labels, rescale and label values while detecting slow/fast keywords
-"$CHRONYC" tracking | sed -e 1d -e 3d -e "s/.*://" | \
-	awk -v FAC="$fieldfactors" -v NAM="$fields" \
-	'BEGIN { split(FAC,factors," "); split(NAM,names," ");
-	{ /slow/ ? SIGN=-1 : SIGN=1 ; print names[NR]".value ",SIGN*$1*factors[NR]}'
+chrony_status="$("$CHRONYC" tracking)"
+echo "$fields" | while read fieldname factor regex label; do
+	status_line="$(echo "$chrony_status" | grep -i -- "$regex " | cut -d ":" -f 2-)"
+	if [ -z "$status_line" ]; then
+		value="U"
+	else
+		# the keyword "slow" indicates negative values
+		value="$(echo "$status_line" | awk '{ /slow/ ? SIGN=-1 : SIGN=1; print $1 * SIGN * '"$factor"' }')"
+	fi
+	echo "${fieldname}.value $value"
+done