contrib: dracut: zfs-lib: simplify ask_for_password

The only user is mount-zfs.sh (non-systemd systems),
so reduce it to what it needs

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes #13291

contrib/dracut/90zfs/mount-zfs.sh.in

@@ -56,9 +56,9 @@ if import_pool "${ZFS_POOL}" ; then
 			if [ "$KEYSTATUS" = "unavailable" ]; then
 				# decrypt them
 				ask_for_password \
-					--tries 5 \
+					5 \
-					--prompt "Encrypted ZFS password for ${ENCRYPTIONROOT}: " \
+					"Encrypted ZFS password for ${ENCRYPTIONROOT}: " \
-					--cmd "zfs load-key '${ENCRYPTIONROOT}'"
+					"zfs load-key '${ENCRYPTIONROOT}'"
 			fi
 		fi
 	fi

contrib/dracut/90zfs/zfs-lib.sh.in

@@ -122,44 +122,14 @@ for_relevant_root_children() {
         )
 }
 
-# ask_for_password
+# ask_for_password tries prompt cmd
 #
 # Wraps around plymouth ask-for-password and adds fallback to tty password ask
 # if plymouth is not present.
-#
-# --cmd command
-#   Command to execute. Required.
-# --prompt prompt
-#   Password prompt. Note that function already adds ':' at the end.
-#   Recommended.
-# --tries n
-#   How many times repeat command on its failure.  Default is 3.
-# --ply-[cmd|prompt|tries]
-#   Command/prompt/tries specific for plymouth password ask only.
-# --tty-[cmd|prompt|tries]
-#   Command/prompt/tries specific for tty password ask only.
-# --tty-echo-off
-#   Turn off input echo before tty command is executed and turn on after.
-#   It's useful when password is read from stdin.
 ask_for_password() {
-    ply_tries=3
+    tries="$1"
-    tty_tries=3
+    prompt="$2"
-    while [ "$#" -gt 0 ]; do
+    cmd="$3"
-        case "$1" in
-            --cmd) ply_cmd="$2"; tty_cmd="$2"; shift;;
-            --ply-cmd) ply_cmd="$2"; shift;;
-            --tty-cmd) tty_cmd="$2"; shift;;
-            --prompt) ply_prompt="$2"; tty_prompt="$2"; shift;;
-            --ply-prompt) ply_prompt="$2"; shift;;
-            --tty-prompt) tty_prompt="$2"; shift;;
-            --tries) ply_tries="$2"; tty_tries="$2"; shift;;
-            --ply-tries) ply_tries="$2"; shift;;
-            --tty-tries) tty_tries="$2"; shift;;
-            --tty-echo-off) tty_echo_off=yes;;
-            *) echo "ask_for_password(): wrong opt '$1'" >&2;;
-        esac
-        shift
-    done
 
     {
         flock -s 9
@@ -167,26 +137,19 @@ ask_for_password() {
         # Prompt for password with plymouth, if installed and running.
         if plymouth --ping 2>/dev/null; then
             plymouth ask-for-password \
-                --prompt "$ply_prompt" --number-of-tries="$ply_tries" | \
+                --prompt "$prompt" --number-of-tries="$tries" | \
-                eval "$ply_cmd"
+                eval "$cmd"
             ret=$?
         else
-            if [ "$tty_echo_off" = yes ]; then
-                stty_orig="$(stty -g)"
-                stty -echo
-            fi
-
             i=1
-            while [ "$i" -le "$tty_tries" ]; do
+            while [ "$i" -le "$tries" ]; do
-                [ -n "$tty_prompt" ] && \
+                printf "%s [%i/%i]:" "$prompt" "$i" "$tries" >&2
-                    printf "%s [%i/%i]:" "$tty_prompt" "$i" "$tty_tries" >&2
+                eval "$cmd" && ret=0 && break
-                eval "$tty_cmd" && ret=0 && break
                 ret=$?
                 i=$((i+1))
-                [ -n "$tty_prompt" ] && printf '\n' >&2
+                printf '\n' >&2
             done
             unset i
-            [ "$tty_echo_off" = yes ] && stty "$stty_orig"
         fi
     } 9>/.console_lock