Merge pull request #1046 from pi-hole/tweak/subshells

Tweak/subshells

automated install/basic-install.sh

@@ -63,7 +63,7 @@ else
   echo ":::"
   echo "::: Detecting the presence of the sudo utility for continuation of this install..."
 
-  if [ -x "$(command -v sudo)" ]; then
+  if command -v sudo &> /dev/null; then
     echo "::: Utility sudo located."
     exec curl -sSL https://install.pi-hole.net | sudo bash "$@"
     exit $?
@@ -75,7 +75,7 @@ fi
 
 # Compatibility
 
-if [[ $(command -v apt-get) ]]; then
+if command -v apt-get &> /dev/null; then
   #Debian Family
   #############################################
   PKG_MANAGER="apt-get"
@@ -100,9 +100,9 @@ if [[ $(command -v apt-get) ]]; then
   package_check_install() {
     dpkg-query -W -f='${Status}' "${1}" 2>/dev/null | grep -c "ok installed" || ${PKG_INSTALL} "${1}"
   }
-elif [ $(command -v rpm) ]; then
+elif command -v rpm &> /dev/null; then
   # Fedora Family
-  if [ $(command -v dnf) ]; then
+  if command -v dnf &> /dev/null; then
     PKG_MANAGER="dnf"
   else
     PKG_MANAGER="yum"
@@ -420,7 +420,7 @@ setStaticIPv4() {
         echo "USERCTL=no"
       }> "${IFCFG_FILE}"
       ip addr replace dev "${PIHOLE_INTERFACE}" "${IPV4_ADDRESS}"
-      if [ -x "$(command -v nmcli)" ];then
+      if command -v nmcli &> /dev/null;then
         # Tell NetworkManager to read our new sysconfig file
         nmcli con load "${IFCFG_FILE}" > /dev/null
       fi
@@ -680,7 +680,7 @@ stop_service() {
   # Can softfail, as process may not be installed when this is called
   echo ":::"
   echo -n "::: Stopping ${1} service..."
-  if [ -x "$(command -v systemctl)" ]; then
+  if command -v systemctl &> /dev/null; then
     systemctl stop "${1}" &> /dev/null || true
   else
     service "${1}" stop &> /dev/null || true
@@ -693,7 +693,7 @@ start_service() {
   # This should not fail, it's an error if it does
   echo ":::"
   echo -n "::: Starting ${1} service..."
-  if [ -x "$(command -v systemctl)" ]; then
+  if command -v systemctl &> /dev/null; then
     systemctl restart "${1}" &> /dev/null
   else
     service "${1}" restart &> /dev/null
@@ -705,7 +705,7 @@ enable_service() {
   # Enable service so that it will start with next reboot
   echo ":::"
   echo -n "::: Enabling ${1} service to start on reboot..."
-  if [ -x "$(command -v systemctl)" ]; then
+  if command -v systemctl &> /dev/null; then
     systemctl enable "${1}" &> /dev/null
   else
     update-rc.d "${1}" defaults &> /dev/null
@@ -862,10 +862,10 @@ create_pihole_user() {
 
 configureFirewall() {
   # Allow HTTP and DNS traffic
-  if [ -x "$(command -v firewall-cmd)" ]; then
+  if command -v firewall-cmd &> /dev/null; then
     firewall-cmd --state &> /dev/null && ( echo "::: Configuring firewalld for httpd and dnsmasq.." && firewall-cmd --permanent --add-port=80/tcp && firewall-cmd --permanent --add-port=53/tcp \
     && firewall-cmd --permanent --add-port=53/udp && firewall-cmd --reload) || echo "::: FirewallD not enabled"
-  elif [ -x "$(command -v iptables)" ]; then
+  elif command -v iptables &> /dev/null; then
     echo "::: Configuring iptables for httpd and dnsmasq.."
     iptables -A INPUT -p tcp -m tcp --dport 80 -j ACCEPT
     iptables -A INPUT -p tcp -m tcp --dport 53 -j ACCEPT
@@ -947,7 +947,7 @@ updatePihole() {
 
 
 checkSelinux() {
-  if [ -x "$(command -v getenforce)" ]; then
+  if command -v getenforce &> /dev/null; then
     echo ":::"
     echo -n "::: SELinux Support Detected... Mode: "
     enforceMode=$(getenforce)