Similar to r251236, improve the portion of dialog(1) API in dialog.subr

responsible for retrieving stored input (for the --inputbox and --password
widgets).

When we (Ron McDowell and I) developed the first version of bsdconfig, it
used temporary files to store responses from dialog(1). That hasn't been
true for a very long time, so the need to always execute some clean-up
function is long-deprecated. The function that used to perform these clean-
up routines for these widgets was f_dialog_inputstr().

We really don't need f_dialog_inputstr() for its originally designed purpose
as all dialog invocations no longer require temporary files.

Just as in r251236, redesign f_dialog_inputstr() in the following four ways:

1. Rename f_dialog_inputstr() to f_dialog_inputstr_fetch()
2. Introduce the new first-argument of $var_to_set to reduce forking
3. Create a corresponding f_dialog_inputstr_store() to abstract storage
4. Offload the sanitization to a new function, f_dialog_line_sanitize()

It should be noted that f_dialog_line_sanitize() -- unlike its cousin from
SVN r251236, f_dialog_data_sanitize() -- trims leading/trailing whitespace
from the user's input. This helps prevent errors and common mistakes caused
by the fact that the new cdialog implementation allows the right-arrow
cursor key to go beyond the last byte of realtime input (adding whitespace
at the end of the typed value).

While we're centralizing the sanitization, let's rewrite f_dialog_input()
while we're here to likewise reduce forking. The f_dialog_input() function
now expects the first argument of $var_to_set instead of producing results
on standard-out.

These changes greatly improve readability and also improve performance.

1 files changed, 3 insertions, 3 deletions

diff --git a/usr.sbin/bsdconfig/console/saver b/usr.sbin/bsdconfig/console/saver
index f2c9cf7..d0150a7 100755
--- a/usr.sbin/bsdconfig/console/saver
+++ b/usr.sbin/bsdconfig/console/saver
@@ -183,9 +183,9 @@ while :; do
 		break ;;
 	"$msg_timeout") # Set the screen saver timeout interval
 		f_dialog_title "$msg_value_required"
-		blanktime=$( f_dialog_input "$msg_enter_timeout_period" \
-		                            "$( f_sysrc_get blanktime )"
-		           ) && f_sysrc_set blanktime "$blanktime"
+		f_dialog_input blanktime "$msg_enter_timeout_period" \
+		               "$( f_sysrc_get blanktime )" &&
+			f_sysrc_set blanktime "$blanktime"
 		f_dialog_title_restore
 		;;
 	esac