bin/setup_screens: Fixing and simplifying various things with the help of shellcheck. Using a separate get_display function to retrieve DISPLAY.

1 files changed, 36 insertions, 30 deletions

diff --git a/bin/setup_screens b/bin/setup_screens
index 1a84bba..7cd0b17 100755
--- a/bin/setup_screens
+++ b/bin/setup_screens
@@ -2,23 +2,29 @@
 # Script to setup screens on login and lid-switch-action
 # Uses autorandr to determine which screens are connected and which to setup.
 #
-# Per default a configuration named "internal" will be used, if the computer is
+# Per default a configuration named "default" will be used, if the computer is
 # a laptop and not docked.
 # A configuration named "docked-closed" will be used during login, when the lid
 # is closed and docked.
-# A configuration named "docked-open" will be used during login, when the lid
+# A configuration named "docked-all" will be used during login, when the lid
 # is open and docked.
 
 set -e -u
 
 lid_state=""
-docking_state=""
 fingerprint=""
 action=""
 x_user=""
+display=""
 current_user=""
 path=""
 
+# get DISPLAY number
+get_display()
+{
+  display=$(pgrep -a Xorg|cut -d':' -f2| cut -d' ' -f1)
+}
+
 # get current user running X
 get_x_user()
 {
@@ -41,15 +47,17 @@ get_path()
 function get_lid_state()
 {
   if [ -r "/proc/acpi/button/lid/LID/state" ]; then
-    lid_state="$(cat /proc/acpi/button/lid/LID/state|awk '{print $2}')"
+    lid_state="$(awk '{print $2}' /proc/acpi/button/lid/LID/state)"
   fi
 }
 
 # Get current docking state ("true" or "false")
-function get_docking_state()
+function is_docked()
 {
-  if [ -x "/usr/bin/busctl" ]; then
-    docking_state="$(busctl introspect org.freedesktop.login1 /org/freedesktop/login1|grep "\.Docked"|awk '{print $4}')"
+  if command -v busctl > /dev/null; then
+    busctl introspect org.freedesktop.login1 /org/freedesktop/login1| grep -E '^.Docked'| awk '{print $4}'
+  else
+    echo false
   fi
 }
 
@@ -63,8 +71,8 @@ function get_setup_fingerprint()
 function get_configuration_fingerprint()
 {
   local fingerprint=""
-  if [ -r $HOME/.config/autorandr/$1/setup ]; then
-    fingerprint="$(md5sum $HOME/.config/autorandr/$1/setup| cut -d ' ' -f 1)"
+  if [ -r "$HOME/.config/autorandr/$1/setup" ]; then
+    fingerprint="$(md5sum "$HOME/.config/autorandr/$1/setup"| cut -d ' ' -f 1)"
   fi
   echo "$fingerprint"
 }
@@ -73,19 +81,19 @@ function set_configuration()
 {
   local state=0
   # if the computer is docked
-  if [ "$docking_state" = "true" ]; then
+  if is_docked ; then
     # if there's a lid-switch action
     if [ -n "$action" ]; then
       case "$action" in 
         "open")
-          if [ $(get_configuration_fingerprint "docked-open")  == "$fingerprint" ]; then
-            echo "Loading docked-open."
+          if [ "$(get_configuration_fingerprint 'docked-all')"  == "$fingerprint" ]; then
+            echo "Loading docked-all."
             state=1
-            autorandr -l docked-open
+            autorandr -l docked-all
           fi
           ;;
         "close")
-          if [ $(get_configuration_fingerprint "docked-closed") == "$fingerprint" ]; then
+          if [ "$(get_configuration_fingerprint 'docked-closed')" == "$fingerprint" ]; then
             echo "Loading docked-closed."
             state=1
             autorandr -l docked-closed
@@ -96,10 +104,10 @@ function set_configuration()
       # check the lid state
       case "$lid_state" in
         "open")
-          if [[ $(get_configuration_fingerprint "docked-open") == "$fingerprint" ]]; then
-            echo "Loading docked-open."
+          if [[ $(get_configuration_fingerprint "docked-all") == "$fingerprint" ]]; then
+            echo "Loading docked-all."
             state=1
-            autorandr -l docked-open
+            autorandr -l docked-all
           fi
           ;;
         "closed")
@@ -125,11 +133,11 @@ function set_configuration()
       fi
     fi
   fi
-  # if the screen still has not been setup, try using internal
+  # if the screen still has not been setup, try using default
   if [ $state -ne 1 ]; then
-    if [[ $(get_configuration_fingerprint "internal") == "$fingerprint" ]]; then
-      echo "Loading internal."
-      autorandr -l internal
+    if [[ $(get_configuration_fingerprint "default") == "$fingerprint" ]]; then
+      echo "Loading default."
+      autorandr -l default
     fi
   fi
 }
@@ -147,27 +155,25 @@ fi
 
 logger "Calling 'setup_screens'"
 get_x_user
+get_display
 get_current_user
 get_path
 
 # Export Xorg DISPLAY and XAUTHORITY
-export DISPLAY=$(ls /tmp/.X*|grep "lock"|cut -d '.' -f2| cut -d '-' -f1|sed -e 's/X/:/')
-export XAUTHORITY="$(eval echo ~$x_user/.Xauthority)"
+export DISPLAY=":$display"
+export XAUTHORITY="/home/$x_user/.Xauthority"
 
 # if the script caller is the current X user or root (and lightdm is the current X user)
-if [ "$current_user" = "$x_user" ] || [ $current_user = "root" -a $x_user = "lightdm" ]; then
+if [ "$current_user" == "$x_user" ]; then
   get_lid_state
-  get_docking_state
   get_setup_fingerprint
   set_configuration
-else
-  if [ $current_user = "root" ]; then
+elif [ "$current_user" == "root" ]; then
     logger "Running $path as user $x_user now."
-    runuser -l $x_user -c $path
-  else
+    runuser -l "$x_user" -c "$path"
+else
     echo "$current_user is not currently running X and is not allowed to let the current X user run this script."
     exit 1
-  fi
 fi
 
 exit 0