fix(service,{invoke,update}-rc.d): fix regressions and refactor

bash_completion

@@ -2207,18 +2207,25 @@ _comp_compgen_xinetd_services()
     fi
 }
 
+# This function completes on SysV init services
+#
+# @since 2.18
+_comp_compgen_sysv_services()
+{
+    local sysvdirs
+    _comp_sysvdirs &&
+        _comp_compgen -U sysvdirs -C "${sysvdirs[0]}" -- \
+            -fX "@($_comp_backup_glob|functions|*.sh|README*|*/*)"
+}
+
 # This function completes on services
 #
 # @return 0 if at least one completion is generated, or 1 otherwise.
 # @since 2.12
 _comp_compgen_services()
 {
-    local sysvdirs
-    _comp_sysvdirs || return 1
-
     local status=1
-    _comp_compgen -U sysvdirs -C "${sysvdirs[0]}" -- -f -X "@($_comp_backup_glob|functions|README)" &&
-        status=0
+    _comp_compgen_sysv_services && status=0
 
     local _generated=$({
         systemctl list-units --full --all ||

completions-core/invoke-rc.d.bash

@@ -7,11 +7,7 @@ _comp_cmd_invoke_rc_d()
     local cur prev words cword comp_args
     _comp_initialize -- "$@" || return
 
-    local sysvdir options
-
-    [[ -d /etc/rc.d/init.d ]] && sysvdir=/etc/rc.d/init.d ||
-        sysvdir=/etc/init.d
-
+    local options
     options=(--help --quiet --force --try-anyway --disclose-deny --query
         --no-fallback)
 
@@ -21,12 +17,15 @@ _comp_cmd_invoke_rc_d()
         local exclude="@(${words[*]})"
         _comp_unlocal IFS
         _comp_compgen -- -W '"${options[@]}"' -X "$exclude"
-        # shellcheck disable=SC2154
-        _comp_compgen -aC "$sysvdir" -- -f -X "@(README*|*.sh|$_comp_backup_glob)"
-    elif [[ -x $sysvdir/$prev ]]; then
+        _comp_compgen -a sysv_services
+        return
+    fi
+
+    local sysvdirs
+    if _comp_sysvdirs && [[ -x ${sysvdirs[0]}/$prev ]]; then
         _comp_compgen_split -- "$(command sed -e 'y/|/ /' \
             -ne 's/^.*Usage:[ ]*[^ ]*[ ]*{*\([^}"]*\).*$/\1/p' \
-            "$sysvdir/$prev")"
+            "${sysvdirs[0]}/$prev")"
     else
         COMPREPLY=()
     fi

completions-core/update-rc.d.bash

@@ -7,13 +7,8 @@ _comp_cmd_update_rc_d()
     local cur prev words cword comp_args
     _comp_initialize -- "$@" || return
 
-    local sysvdir services options
-
-    [[ -d /etc/rc.d/init.d ]] && sysvdir=/etc/rc.d/init.d ||
-        sysvdir=/etc/init.d
-
-    # shellcheck disable=SC2154
-    _comp_compgen -v services -C "$sysvdir" -- -f -X "@(README*|*.sh|$_comp_backup_glob)"
+    local services options
+    _comp_compgen -v services sysv_services
     options=(-f -n)
 
     if [[ $cword -eq 1 || $prev == -* ]]; then