Switch to single quotes in contexts where we may want to use '\'

Inside double quotes, backslash is an escape character. Hence, it is
cleaner to use single quotes where backslashes may occur. This includes
pattern strings for print, grep, and sed.

contrib/bash-completion

@@ -11,7 +11,7 @@ _wireless_interfaces() {
 
 
 _netctl_profiles() {
-    find -L /etc/netctl -maxdepth 1 -type f -not -name '.*' -not -name '*~' -not -name $'*\n*' -not -name '*.action' -not -name '*.conf' -not -name '*.service' -printf "%f\n"
+    find -L /etc/netctl -maxdepth 1 -type f -not -name '.*' -not -name '*~' -not -name $'*\n*' -not -name '*.action' -not -name '*.conf' -not -name '*.service' -printf '%f\n'
 }
 
 

contrib/zsh-completion

@@ -12,7 +12,7 @@ _wireless_interfaces() {
 (( $+function[_netctl_command] )) ||
 _netctl_command() {
     [[ $words[1] = (start|stop|restart|switch-to|is-active|status|enable|disable|reenable|is-enabled|edit|wait-online) ]] &&
-      compadd "${(f)$(find -L /etc/netctl -maxdepth 1 -type f -not -name '.*' -not -name '*~' -not -name $'*\n*' -not -name '*.action' -not -name '*.conf' -not -name '*.service' -printf "%f\n")}"
+      compadd "${(f)$(find -L /etc/netctl -maxdepth 1 -type f -not -name '.*' -not -name '*~' -not -name $'*\n*' -not -name '*.action' -not -name '*.conf' -not -name '*.service' -printf '%f\n')}"
 }
 
 

src/ifplugd.action

@@ -11,7 +11,7 @@ case "$2" in
     while IFS= read -r profile; do
         if ForceConnect=yes "$SUBR_DIR/network" start "$profile"; then
             mkdir -p "$(dirname "$PROFILE_FILE")"
-            printf "%s" "$profile" > "$PROFILE_FILE"
+            printf '%s' "$profile" > "$PROFILE_FILE"
             exit 0
         fi
     done < <(list_profiles | while IFS= read -r profile; do
@@ -26,7 +26,7 @@ case "$2" in
               : ${Priority:=1}
           fi
           is_yes "${ExcludeAuto:-yes}" && exit
-          printf "%i\t%s\n" "${Priority:-0}" "$profile"
+          printf '%i\t%s\n' "${Priority:-0}" "$profile"
           report_debug "Included profile '$profile'"
         )
     done | sort -nrs -k 1,1 | cut -f 2-)

src/lib/connections/wireless

@@ -36,7 +36,7 @@ wireless_up() {
             report_error "Could not create a WPA config file for interface '$Interface'"
             return 1
         fi
-        printf "%s\n" "network={" "$(wpa_make_config_block)" "}" >> "$config_file"
+        printf '%s\n' "network={" "$(wpa_make_config_block)" "}" >> "$config_file"
     fi
 
     # Start the WPA supplicant

src/lib/globals

@@ -106,7 +106,7 @@ timeout_wait() {
 ## List all acceptable profiles names separated by newlines
 list_profiles() {
     # Follow aliases with -L, skip forbidden/reserved names
-    find -L "$PROFILE_DIR/" -maxdepth 1 -type f -not -name '.*' -not -name '*~' -not -name $'*\n*' -not -name '*.action' -not -name '*.conf' -not -name '*.service' -printf "%f\n"
+    find -L "$PROFILE_DIR/" -maxdepth 1 -type f -not -name '.*' -not -name '*~' -not -name $'*\n*' -not -name '*.action' -not -name '*.conf' -not -name '*.service' -printf '%f\n'
 }
 
 ## Sources all hooks and a profile (but no interface configuration)

src/lib/ip

@@ -27,7 +27,7 @@ dhcp_call() {
 resolvconf_add() {
     local interface="$1"
     shift
-    printf "%s\n" "$@" | do_readable resolvconf -a "$interface"
+    printf '%s\n' "$@" | do_readable resolvconf -a "$interface"
 }
 
 

src/lib/wpa

@@ -11,8 +11,8 @@ wpa_call() {
 
     if [[ $WPA_CTRL_DIR ]]; then
         args+=("-p" "$WPA_CTRL_DIR")
-    elif [[ $WPAConfigFile ]] && grep -q "^[[:space:]]*ctrl_interface=" "$WPAConfigFile"; then
-        WPA_CTRL_DIR=$(sed -n "0,/^[[:space:]]*ctrl_interface=/s///p" "$WPAConfigFile")
+    elif [[ $WPAConfigFile ]] && grep -q '^[[:space:]]*ctrl_interface=' "$WPAConfigFile"; then
+        WPA_CTRL_DIR=$(sed -n '0,/^[[:space:]]*ctrl_interface=/s///p' "$WPAConfigFile")
         if [[ $WPA_CTRL_DIR == DIR=* ]]; then
             WPA_CTRL_DIR=${WPA_CTRL_DIR:4}
             WPA_CTRL_DIR=${WPA_CTRL_DIR%% GROUP=*}
@@ -35,7 +35,7 @@ wpa_is_active() {
 # $1: interface name
 wpa_get_state() {
     local state
-    state=$(wpa_call "$1" status | grep -m1 "^wpa_state=") || return 1
+    state=$(wpa_call "$1" status | grep -m1 '^wpa_state=') || return 1
     echo "${state#wpa_state=}"
 }
 
@@ -179,14 +179,14 @@ wpa_quote() {
 wpa_unquote() {
     local string="$1"
     if [[ $string == \"*\" ]]; then
-        printf "%s" "${string:1:-1}"
+        printf '%s' "${string:1:-1}"
     elif [[ $string == +([[:xdigit:]][[:xdigit:]]) ]]; then
         while [[ $string ]]; do
-            printf "\x${string:0:2}"
+            printf "\\x${string:0:2}"
             string=${string:2}
         done
     else
-        printf "%s" "${string}"
+        printf '%s' "${string}"
     fi
 }
 
@@ -239,7 +239,7 @@ wpa_make_config_block() {
         fi
       ;;
       wpa-configsection)
-        printf "%s\n" "${WPAConfigSection[@]}"
+        printf '%s\n' "${WPAConfigSection[@]}"
         return
       ;;
       *)

src/netctl-auto

@@ -123,7 +123,7 @@ switch_to() {
 
     # List of enabled networks
     local enabled_networks=$(wpa_call "$interface" list_networks | tail -n+2 | \
-        cut -f 1,4 | grep -Fv "[DISABLED]" | cut -f 1 | tr "\n" ' ')
+        cut -f 1,4 | grep -Fv '[DISABLED]' | cut -f 1 | tr '\n' ' ')
 
     reenable_networks() {
         for network in $enabled_networks; do
@@ -222,7 +222,7 @@ start() {
           is_yes "${ExcludeAuto:-no}" && exit
           # Set default and exclude wpa-config as it does not fit this scheme
           [[ ${Security:=none} != "wpa-config" ]] || exit
-          printf "%s\n" "network={" "$(wpa_make_config_block)" "id_str=\"$profile\"" "}" >> "$wpa_conf"
+          printf '%s\n' "network={" "$(wpa_make_config_block)" "id_str=\"$profile\"" "}" >> "$wpa_conf"
           report_notice "Included profile '$profile'"
         )
     done

src/netctl.in

@@ -45,7 +45,7 @@ store() {
     mkdir -p "$(dirname "$STATE_FILE")"
     list_profiles | while IFS= read -r Profile; do
         if sd_call "is-active --quiet" "$Profile" &> /dev/null; then
-            printf "%s\n" "$Profile"
+            printf '%s\n' "$Profile"
         fi
     done > "$STATE_FILE"
 }
@@ -65,7 +65,7 @@ stop_all() {
     # We cannot pipe to mapfile, as the end of a pipe is inside a subshell
     mapfile -t Profiles < <(list_profiles)
     if (( ${#Profiles[@]} )); then
-        do_debug sd_call stop "${Profiles[@]}" 2> >(grep -Fv "not loaded" >&2)
+        do_debug sd_call stop "${Profiles[@]}" 2> >(grep -Fv 'not loaded' >&2)
     fi
 }
 
@@ -77,14 +77,14 @@ switch_to() {
     # We assume interface names are not quoted
     # Using read removes leading whitespace
     read InterfaceLine < \
-      <(grep -om1 "^[[:space:]]*Interface=[[:alnum:]:._-]\+" "$1")
+      <(grep -om1 '^[[:space:]]*Interface=[[:alnum:]:._-]\+' "$1")
     if [[ -z $InterfaceLine ]]; then
         exit_error "Profile '$1' does not specify an interface"
     fi
     mapfile -t AllProfiles < <(list_profiles)
     mapfile -t Profiles < <(grep -Fl "$InterfaceLine" "${AllProfiles[@]}")
     if (( ${#Profiles[@]} )); then
-        do_debug sd_call stop "${Profiles[@]}" 2> >(grep -Fv "not loaded" >&2)
+        do_debug sd_call stop "${Profiles[@]}" 2> >(grep -Fv 'not loaded' >&2)
     fi
     do_debug sd_call start "$1"
 }

src/wifi-menu

@@ -30,7 +30,7 @@ quote_safe() {
     if [[ "$1" = \"* ]]; then
         printf '""%s"' "$1"
     else
-        printf "%s" "$1"
+        printf '%s' "$1"
     fi
 }
 
@@ -46,7 +46,7 @@ init_profiles() {
                 if [[ "$ESSID" = \"\"*\" ]]; then
                     ESSID=${ESSID:2:-1}
                 fi
-                printf "%s" "$ESSID"
+                printf '%s' "$ESSID"
                 if [[ "$Description" =~ "Automatically generated" ]]; then
                     return 2
                 else
@@ -105,7 +105,7 @@ ssid_to_profile() {
     local i
     for i in $(seq 0 $((${#ESSIDS[@]}-1))); do
         if [[ "$1" = "${ESSIDS[i]}" ]]; then
-            printf "%s" "${PROFILES[i]}"
+            printf '%s' "${PROFILES[i]}"
             return 0
         fi
     done
@@ -157,7 +157,7 @@ create_profile() {
             fi
         elif [[ ${#key} -ge 8 && ${#key} -le 63 ]]; then
             if is_yes "${OBSCURE:-no}"; then
-                key="\"$(wpa_passphrase "$1" "$key" | sed -n "s/^[[:space:]]*psk=//p")"
+                key="\"$(wpa_passphrase "$1" "$key" | sed -n 's/^[[:space:]]*psk=//p')"
             else
                 key=$(quote_safe "$key")
             fi
@@ -172,11 +172,11 @@ Description='Automatically generated profile by wifi-menu'
 Interface=$INTERFACE
 Connection=wireless
 Security=$security
-ESSID=$(printf "%q" "$(quote_safe "$1")")
+ESSID=$(printf '%q' "$(quote_safe "$1")")
 IP=dhcp
-${key+Key=$(printf "%q" "$key")}
+${key+Key=$(printf '%q' "$key")}
 EOF
-    printf "%s" "$PROFILE"
+    printf '%s' "$PROFILE"
     return 0
 }
 
@@ -263,7 +263,7 @@ if [[ "$RFKill" && "$(rf_status "$INTERFACE" "$RFKill")" ]]; then
 fi
 
 echo -n "Scanning for networks... "
-if CONNECTION=$(wpa_call "$INTERFACE" status 2> /dev/null | grep -m 1 "^ssid="); then
+if CONNECTION=$(wpa_call "$INTERFACE" status 2> /dev/null | grep -m 1 '^ssid='); then
     CONNECTION=$(printf_decode "${CONNECTION#ssid=}")
     CONNECTED=yes
 fi