make work better

bin/volume

@@ -14,13 +14,16 @@ argv0="$0"
 # `volume s` must output the current volume in integer form in whatever units
 # are being used by `volume a` on the given system.
 
-! command -v stris >/dev/null 2>/dev/null \
-	&& printf "%b: Missing stris.\n" "$argv0" \
-	&& exit 1 \
-	|| true
-
 VOLUME_TMP_FILE="$HOME/.volume-previous"
 
+system_determine(){
+	if [ "$(uname)" = NetBSD ]; then
+		printf "NetBSD\n"
+	elif command -v pactl >/dev/null 2>&1; then
+		printf "PulseAudio\n"
+	fi
+}
+
 unknown_system(){
 	printf "%s: Unknown system.\n" "$argv0" 1>&2
 	exit 1
@@ -34,6 +37,7 @@ Functions:
 	'+'      - shortcut to \"relative \$2\"
 	'-'      - shortcut to \"relative -\$2\"
 	absolute - change sound output to absolute unit
+	debug    - show debugging information
 	help,''  - print this help output
 	mute     - toggle mute/unmute
 	relative - change sound output relative to current status
@@ -56,29 +60,27 @@ case "$argv1" in
 #
 # SYSTEM DEPENDENT
 #
-(a*)
-	[ -n "$2" ] && [ -z "$3" ] && stris int "$2" || usage 
-
-	if [ "$(uname)" = "NetBSD" ]; then
+a*) [ -n "$2" ] || usage
+	case "$(system_determine)" in
+	NetBSD)
 		# NetBSD 9.2 STABLE 2021-07
 		audioctl -w play.gain=$2 >/dev/null
-
-	elif command -v pactl >/dev/null; then
+		;;
+	PulseAudio)
 		# pactl 15.0 compiled+linked with libpulse 15.0.0
 		pactl set-sink-volume @DEFAULT_SINK@ $2%
+		;;
+	*)	unknown_system ;;
+	esac; exit 0 ;;
 
-	else	unknown_system; fi
-	exit 0 ;;
-(s*)
-	[ -z "$2" ] || usage
-
-	if [ "$(uname)" = "NetBSD" ]; then
-		# hacky
+s*) [ -z "$2" ] || usage
+	case "$(system_determine)" in
+	NetBSD) # hacky
 		audioctl -a \
 			| grep "play\.gain" \
 			| cut -d '=' -f 2
-
-	elif command -v pactl >/dev/null; then
+		;;
+	PulseAudio)
 		# really hacky, gets the job done
 		# gets the volume % of Lchan specifically
 		pactl get-sink-volume @DEFAULT_SINK@ \
@@ -86,32 +88,31 @@ case "$argv1" in
 			| cut -d '/' -f 2 \
 			| xargs echo \
 			| sed s/'%'//
+		;;
+	*)	unknown_system ;;
+	esac; exit 0 ;;
 
-	else	unknown_system; fi
-	exit 0 ;;
 #
 # SYSTEM independent
 #
-(+)
-	[ -n "$2" ] && [ -z "$3" ] && stris uint "$2" \
-		&& "$argv0" r "$2" \
-		|| usage
-	;;
-(-)
-	[ -n "$2" ] && [ -z "$3" ] && stris uint "$2" \
-		&& "$argv0" r -"$2" \
-		|| usage
-	;;
-(m*)
-	[ -z "$2" ] || usage
++) "$argv0" r  "$2" ;;
+-) "$argv0" r -"$2" ;;
+
+d*)
+	printf '$0: %s\nAudio system detected: %s\n' \
+		"$argv0" \
+		"$(system_determine)"
+	exit 0 ;;
+
+m*) [ -z "$2" ] || usage
 	# restore previous volume if there is one
 	if [ -e "$VOLUME_TMP_FILE" ]; then
-		"$argv0" a "$(cat "$VOLUME_TMP_FILE")" \
+		xargs "$argv0" a <"$VOLUME_TMP_FILE" \
 			&& rm "$VOLUME_TMP_FILE" \
 			&& printf "Unmuted.\n" \
 			&& exit 0 \
 			|| printf "Error restoring previous volume.\n" \
-				>/dev/stderr \
+				1>&2 \
 			&& exit 1
 	fi
 
@@ -120,10 +121,10 @@ case "$argv1" in
 	# dd used rather than shell redirect so it's easy to determine
 	# whether or not the file write worked
 	if ! printf "%b" "$("$argv0" s)" \
-				| dd >"$VOLUME_TMP_FILE" 2>/dev/null
+				| dd of="$VOLUME_TMP_FILE" 2>/dev/null
 	then
-		printf "Error writing to file.\n" >/dev/stderr
-		false
+		printf "Error writing to file.\n" 1>&2
+		exit 1
 	fi
 
 	# and then of course mute
@@ -131,16 +132,13 @@ case "$argv1" in
 	printf "Muted.\n"
 
 	exit 0 ;;
-(r*)
-	[ -n "$2" ] && [ -z "$3" ] && stris int "$2" \
-		|| usage
 
-	if ! newval=$(add $("$argv0" s) $2) || ! stris int "$newval"; then
-		printf "%b: Error finding new value for volume.\n" "$argv0"
-		exit 1
-	fi
-	"$argv0" a $newval
+r*)
+	! newval=$(printf "%s %s + p\n" $("$argv0"s) "$2" | dc) \
+		&& printf "%b: Error finding new value for volume.\n" "$argv0" \
+		&& exit 1
+	"$argv0" a "$newval"
 	exit $? ;;
-(h*)	usage ;;
-(*)	usage ;;
+
+*)	usage ;;
 esac