common: introduce usearg and use it

bin/rpmbs

@@ -232,8 +232,7 @@ if [ -n "$UPLOADNOW" ] && is_gear $SPECDIR ; then
 	if [ -n "$TASKNUMBER" ] ; then
 		docmd ssh $GIRARHOST task add $TASKNUMBER repo $PROJECTNAME $TAG 2>&1 | tee $RPMDIR/uploaded.log.tmp
 	else
-		[ -n "$POCKET" ] && POCKETARG="-p $POCKET" || POCKETARG=""
-		docmd ssh $GIRARHOST build -b $BINARYREPO $POCKETARG $PROJECTNAME $TAG 2>&1 | tee $RPMDIR/uploaded.log.tmp
+		docmd ssh $GIRARHOST build -b $BINARYREPO $(usearg -p $POCKET) $PROJECTNAME $TAG 2>&1 | tee $RPMDIR/uploaded.log.tmp
 	fi
 	# FIXME: incorporate
 	cat $RPMDIR/uploaded.log.tmp | grep task | head -n2 | tail -n1 >> $RPMDIR/uploaded.log

share/eterbuild/functions/common

@@ -312,3 +312,13 @@ showcmd()
 	echo " \$ $@"
 	SETCOLOR_NORMAL
 }
+
+# Example: $ command $(usearg -d "$PARAM")
+# will add -d "$PARAM" if $PARAM is not empty
+usearg()
+{
+        local ARG=$1
+        shift
+        [ -n "$1" ] && echo "$ARG $@"
+}
+

tests/test_usearg.sh

+#!/bin/sh
+
+. `dirname $0`/../share/eterbuild/functions/common
+#load_mod spec
+
+check()
+{
+	[ "$2" != "$3" ] && echo "FATAL with '$1': result '$2' do not match with '$3'" || echo "OK for '$1' with '$2'"
+}
+
+echo "$(usearg -f TEST)"
+echo "$(usearg -f TEST MORE)"
+echo "$(usearg -f $TEST)"
+TEST=124
+echo "$(usearg -f $TEST)"