Grab wifi status from iwconfig instead of nmcli

which reduces our resource footprint

diff --git a/README.md b/README.md
index 12d9f70..2bf2f0d 100644 (file)
--- a/README.md
+++ b/README.md
@@ -109,6 +109,3 @@ TODO
     - priority
     - snooze time (if already alerted, when to re-alert?)
     - text: subject/body
-- Reduce wireless sensor resource footprint:
-    - use `nmcli monitor`, instead of polling, for state changes
-    - use `iwconfig`, instead of `nmcli`, for SSID and signal strength

diff --git a/bin/khatus b/bin/khatus
index bf4db40..6ae08b0 100755 (executable)
--- a/bin/khatus
+++ b/bin/khatus
@@ -54,6 +54,7 @@ main() {
         ["--weather_station_id"]='KJFK'
         ["--screen_brightness_device_name"]='acpi_video0'
         ["--prefixes_of_net_interfaces_to_show"]='w'  # comma-separated
+        ["--wifi_interface"]=''
         ["--disk_space_device"]='/'
         ["--disk_io_device"]='sda'
         ["--thermal_zone"]=0
@@ -105,6 +106,12 @@ main() {
         esac
     done
 
+    if [ "${opts['--wifi_interface']}" = ''  ]
+    then
+        echo 'Please provide the required parameter: --wifi_interface' >&2
+        exit 1
+    fi
+
     (
         echo '=============================================='
         echo "Khatus starting with the following parameters:"
@@ -140,6 +147,7 @@ main() {
     cmd_sens_mpd_state="khatus_sensor_mpd_state $bin"
     cmd_sens_net_addr_io="khatus_sensor_net_addr_io $bin"
     cmd_sens_volume="khatus_sensor_volume $bin"
+    cmd_sens_wifi="khatus_sensor_net_wifi_status $bin ${opts['--wifi_interface']}"
 
     fork_watcher                                       "$pipe" "$bin" "khatus_sensor_energy $bin"     'in:ENERGY'
     fork_poller "${opts['--interval_inp_datetime']}"   "$pipe" "$bin" khatus_sensor_datetime          'in:DATE_TIME'
@@ -149,7 +157,7 @@ main() {
     fork_poller "${opts['--interval_inp_mpd_song']}"   "$pipe" "$bin" khatus_sensor_mpd_song          'in:MPD_SONG'
     fork_poller "${opts['--interval_inp_volume']}"     "$pipe" "$bin" "$cmd_sens_volume"              'in:VOLUME'
     fork_poller "${opts['--interval_inp_bluetooth']}"  "$pipe" "$bin" "$cmd_sens_bluetooth"           'in:BLUETOOTH_POWER'
-    fork_poller "${opts['--interval_inp_net_wifi']}"   "$pipe" "$bin" khatus_sensor_net_wifi_status   'in:NET_WIFI_STATUS'
+    fork_poller "${opts['--interval_inp_net_wifi']}"   "$pipe" "$bin" "$cmd_sens_wifi"                'in:NET_WIFI_STATUS'
     fork_poller "${opts['--interval_inp_net_io']}"     "$pipe" "$bin" "$cmd_sens_net_addr_io"         'in:NET_ADDR_IO'
     fork_poller "${opts['--interval_inp_disk_space']}" "$pipe" "$bin" "$cmd_sens_disk_space"          'in:DISK_SPACE'
     fork_poller "${opts['--interval_inp_disk_io']}"    "$pipe" "$bin" "$cmd_sens_disk_io"             'in:DISK_IO'

diff --git a/bin/khatus_controller b/bin/khatus_controller
index de971b2..c67e640 100755 (executable)
--- a/bin/khatus_controller
+++ b/bin/khatus_controller
@@ -97,7 +97,7 @@
 {
     shift()
     shift()
-    db["net_wifi_status"] = $0
+    set_net_wifi_status()
 }
 
 /^OK in:BLUETOOTH_POWER/\
@@ -338,6 +338,12 @@ function set_disk_io(    curr_w, curr_r, prev_w, prev_r) {
     db["disk_io_diff_r"] = curr_r - prev_r
 }
 
+function set_net_wifi_status(    interface) {
+    interface = $1
+    shift()
+    db["net_wifi_status", interface] = $0
+}
+
 function set_net_addr_io(    \
     interface, address, io_curr_w, io_curr_r, io_prev_w, io_prev_r\
 ) {
@@ -475,7 +481,7 @@ function make_status_net(    \
                     io_stat = "--"
                 }
                 if (interface ~ "^w") {
-                    label = label ":" db["net_wifi_status"]
+                    label = label ":" db["net_wifi_status", interface]
                 }
                 if (++count_printed > 1) {
                     sep = "  "

diff --git a/bin/khatus_parse_iwconfig b/bin/khatus_parse_iwconfig
new file mode 100755 (executable)
index 0000000..9a18cfa
--- /dev/null
+++ b/bin/khatus_parse_iwconfig
@@ -0,0 +1,37 @@
+#! /usr/bin/awk -f
+#
+# Example iwconfig output:
+# -----------------------
+# $ iwconfig wlp3s0
+# wlp3s0    IEEE 802.11  ESSID:"BPLUNWIRED"
+#           Mode:Managed  Frequency:5.785 GHz  Access Point: E2:55:2D:C0:64:B8
+#           Bit Rate=135 Mb/s   Tx-Power=15 dBm
+#           Retry short limit:7   RTS thr:off   Fragment thr:off
+#           Power Management:on
+#           Link Quality=59/70  Signal level=-51 dBm
+#           Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
+#           Tx excessive retries:0  Invalid misc:0   Missed beacon:0
+#
+#
+# USAGE: khatus_parse_iwconfig -v requested_interface="$wifi_interface"
+
+/^[a-z0-9]+ +IEEE 802\.11 +ESSID:/ {
+    interface = $1
+    split($4, essid_parts, ":")
+    essid[interface] = essid_parts[2]
+    gsub("\"", "", essid[interface])
+}
+
+/^ +Link Quality=[0-9]+\/[0-9]+ +Signal level=/ {
+    split($2, lq_parts_eq, "=")
+    split(lq_parts_eq[2], lq_parts_slash, "/")
+    cur = lq_parts_slash[1]
+    max = lq_parts_slash[2]
+    link[interface] = cur / max * 100
+}
+
+END {
+    i = requested_interface
+    status = link[i] ? sprintf("%s %s:%d%%", i, essid[i], link[i]) : "--"
+    print(status)
+}

diff --git a/bin/khatus_sensor_net_wifi_status b/bin/khatus_sensor_net_wifi_status
index de7fd58..033572a 100755 (executable)
--- a/bin/khatus_sensor_net_wifi_status
+++ b/bin/khatus_sensor_net_wifi_status
@@ -2,14 +2,8 @@
 
 set -e
 
-nmcli \
-    -f ACTIVE,SSID,SIGNAL \
-    -t \
-    d wifi \
-| awk \
-    -F ':' \
-    '
-    BEGIN       {wifi_status = "--"}
-    $1 == "yes" {wifi_status =  $2 ":" $3 "%"}
-    END         {print wifi_status}
-    '
+dir_bin="$1"
+wifi_interface="$2"
+
+iwconfig "$wifi_interface" \
+| "$dir_bin"/khatus_parse_iwconfig -v requested_interface="$wifi_interface"