fix division by zero in charts.d ap module - also optimize it to call awk once per...

diff --git a/charts.d/ap.chart.sh b/charts.d/ap.chart.sh
index 0e85c486dc95daedb9404d680ac37f42f5a70dfc..ce2eefc9f1ad9a1409678819a4815e27ff7d70c7 100644 (file)
--- a/charts.d/ap.chart.sh
+++ b/charts.d/ap.chart.sh
@@ -16,7 +16,7 @@ declare -A ap_devs=()
 # _check is called once, to find out if this chart should be enabled or not
 ap_check() {
        require_cmd iw || return 1
-       
+
        local ev=$(run iw dev | awk '
                BEGIN {
                        i = "";
@@ -77,20 +77,19 @@ DIMENSION retries 'tx retries' incremental 1 1
 DIMENSION failures 'tx failures' incremental -1 1
 
 CHART ap_signal.${dev} '' "Average Signal for ${ssid} on ${dev}" "dBm" ${dev} ap.signal line $((ap_priority + 5)) $ap_update_every
-DIMENSION signal 'average signal' absolute 1 1
+DIMENSION signal 'average signal' absolute 1 1000
 
 CHART ap_bitrate.${dev} '' "Bitrate for ${ssid} on ${dev}" "Mbps" ${dev} ap.bitrate line $((ap_priority + 6)) $ap_update_every
 DIMENSION receive '' absolute 1 1000
 DIMENSION transmit '' absolute -1 1000
 DIMENSION expected 'expected throughput' absolute 1 1000
 EOF
-
        done
 
        return 0
 }
 
-# _update is called continiously, to collect the values
+# _update is called continuously, to collect the values
 ap_update() {
        # the first argument to this function is the microseconds since last update
        # pass this parameter to the BEGIN statement (see bellow).
@@ -101,66 +100,81 @@ ap_update() {
 
        for dev in "${!ap_devs[@]}"
        do
-               iw ${dev} station dump |\
-                       awk "
-                               BEGIN {
-                                       c = 0;
-                                       rb = 0;
-                                       tb = 0;
-                                       rp = 0;
-                                       tp = 0;
-                                       tr = 0;
-                                       tf = 0;
-                                       tt = 0;
-                                       rt = 0;
-                                       s = 0;
-                                       g = 0;
-                                       e = 0;
-                               }
-                               /^Station/           { c++; }
-                               /^[ \\t]+rx bytes:/   { rb += \$3 }
-                               /^[ \\t]+tx bytes:/   { tb += \$3 }
-                               /^[ \\t]+rx packets:/ { rp += \$3 }
-                               /^[ \\t]+tx packets:/ { tp += \$3 }
-                               /^[ \\t]+tx retries:/ { tr += \$3 }
-                               /^[ \\t]+tx failed:/  { tf += \$3 }
-                               /^[ \\t]+signal:/     { s  += \$2; }
-                               /^[ \\t]+rx bitrate:/ { x = \$3; rt += x * 1000; }
-                               /^[ \\t]+tx bitrate:/ { x = \$3; tt += x * 1000; }
-                               /^[ \\t]+expected throughput:(.*)Mbps/ {
-                                       x=\$3;
-                                       sub(/Mbps/, \"\", x);
-                                       e += x * 1000;
-                               }
-                               END {
-                                       print \"BEGIN ap_clients.${dev}\"
-                                       print \"SET clients = \" c;
-                                       print \"END\"
-                                       print \"BEGIN ap_bandwidth.${dev}\"
-                                       print \"SET received = \" rb;
-                                       print \"SET sent = \" tb;
-                                       print \"END\"
-                                       print \"BEGIN ap_packets.${dev}\"
-                                       print \"SET received = \" rp;
-                                       print \"SET sent = \" tp;
-                                       print \"END\"
-                                       print \"BEGIN ap_issues.${dev}\"
-                                       print \"SET retries = \" tr;
-                                       print \"SET failures = \" tf;
-                                       print \"END\"
-                                       print \"BEGIN ap_signal.${dev}\"
-                                       print \"SET signal = \" s / c;
-                                       print \"END\"
-
-                                       if( c == 0 ) c = 1;
-                                       print \"BEGIN ap_bitrate.${dev}\"
-                                       print \"SET receive = \" rt / c;
-                                       print \"SET transmit = \" tt / c;
-                                       print \"SET expected = \" e / c;
-                                       print \"END\"
-                               }
-                               "
-       done
+           echo
+           echo "DEVICE ${dev}"
+               iw ${dev} station dump
+       done | awk "
+        function zero_data() {
+            dev = \"\";
+            c = 0;
+            rb = 0;
+            tb = 0;
+            rp = 0;
+            tp = 0;
+            tr = 0;
+            tf = 0;
+            tt = 0;
+            rt = 0;
+            s = 0;
+            g = 0;
+            e = 0;
+        }
+        function print_device() {
+            if(dev != \"\" && length(dev) > 0) {
+                print \"BEGIN ap_clients.\" dev;
+                print \"SET clients = \" c;
+                print \"END\";
+                print \"BEGIN ap_bandwidth.\" dev;
+                print \"SET received = \" rb;
+                print \"SET sent = \" tb;
+                print \"END\";
+                print \"BEGIN ap_packets.\" dev;
+                print \"SET received = \" rp;
+                print \"SET sent = \" tp;
+                print \"END\";
+                print \"BEGIN ap_issues.\" dev;
+                print \"SET retries = \" tr;
+                print \"SET failures = \" tf;
+                print \"END\";
+
+                if( c == 0 ) c = 1;
+                print \"BEGIN ap_signal.\" dev;
+                print \"SET signal = \" int(s / c);
+                print \"END\";
+                print \"BEGIN ap_bitrate.\" dev;
+                print \"SET receive = \" int(rt / c);
+                print \"SET transmit = \" int(tt / c);
+                print \"SET expected = \" int(e / c);
+                print \"END\";
+            }
+            zero_data();
+        }
+        BEGIN {
+            zero_data();
+        }
+        /^DEVICE / {
+            print_device();
+            dev = \$2;
+        }
+        /^Station/            { c++; }
+        /^[ \\t]+rx bytes:/   { rb += \$3; }
+        /^[ \\t]+tx bytes:/   { tb += \$3; }
+        /^[ \\t]+rx packets:/ { rp += \$3; }
+        /^[ \\t]+tx packets:/ { tp += \$3; }
+        /^[ \\t]+tx retries:/ { tr += \$3; }
+        /^[ \\t]+tx failed:/  { tf += \$3; }
+        /^[ \\t]+signal:/     { x = \$2; s  += x * 1000; }
+        /^[ \\t]+rx bitrate:/ { x = \$3; rt += x * 1000; }
+        /^[ \\t]+tx bitrate:/ { x = \$3; tt += x * 1000; }
+        /^[ \\t]+expected throughput:(.*)Mbps/ {
+            x=\$3;
+            sub(/Mbps/, \"\", x);
+            e += x * 1000;
+        }
+        END {
+            print_device();
+        }
+    "
 
        return 0
 }