Avoid the possibility of app settings file being changed while it is being parsed

src/freedombone-installer

@@ -1616,28 +1616,32 @@ function update_app_settings {
     if [ ! -f "$appsettings_file" ]; then
         return
     fi
+    settings_data=$(cat "$appsettings_file")
+    rm "$appsettings_file"
+
     cp "$appsettings_file" "$webadmin_install_dir/appsettings.txt"
     echo '' >> "$webadmin_install_dir/appsettings.txt"
     echo 'update_app_settings' >> "$webadmin_install_dir/appsettings.txt"
-    if grep -q ',' "$appsettings_file"; then
-        app_name=$(awk -F ',' '{print $1}' < "$appsettings_file")
+    if [[ "$settings_data" == *','* ]]; then
+        app_name=$(echo "$settings_data" | awk -F ',' '{print $1}')
         echo "app_name: ${app_name}" >> "$webadmin_install_dir/appsettings.txt"
         if [ "$app_name" ]; then
             app_filename="/usr/share/${PROJECT_NAME}/apps/${PROJECT_NAME}-app-${app_name}"
             echo "app_filename: ${app_filename}" >> "$webadmin_install_dir/appsettings.txt"
             if [ -f "$app_filename" ]; then
-                app_function=$(awk -F ',' '{print $2}' < "$appsettings_file")
+                app_function=$(echo "$settings_data" | awk -F ',' '{print $2}')
                 echo "app_function: ${app_function}" >> "$webadmin_install_dir/appsettings.txt"
                 if [ "$app_function" ]; then
                     if grep -q "function setting_${app_function} {" "$app_filename"; then
-                        app_value=$(awk -F ',' '{print $3}' < "$appsettings_file")
-                        echo "app_value: ${app_value}" >> "$webadmin_install_dir/appsettings.txt"
+                        app_value=$(echo "$settings_data" | awk -F ',' '{print $3}')
 
-                        echo "test123" >> "$webadmin_install_dir/appsettings.txt"
+                        echo "app_value: ${app_value}" >> "$webadmin_install_dir/appsettings.txt"
                         echo "script: $appsettings_script" >> "$webadmin_install_dir/appsettings.txt"
+
                         check_for_existing_processes $appsettings_script
 
                         ls -l $appsettings_script >> "$webadmin_install_dir/appsettings.txt"
+
                         { echo "echo \"Beginning webadmin ${app_name} app settings change \$(date)\"";
                           echo "PROJECT_NAME=$PROJECT_NAME";
                           echo "source $app_filename";
@@ -1658,7 +1662,6 @@ function update_app_settings {
         echo 'No settings specified' >> "$webadmin_install_dir/appsettings.txt"
         chown www-data:www-data "$webadmin_install_dir/appsettings.txt"
     fi
-    rm "$appsettings_file"
 }
 
 # If the freedombone command is already running then kill its process