obs: build_all.sh: Add usage function (refactor)

Add usage function.

Signed-off-by: Jose Carlos Venegas Munoz <jose.carlos.venegas.munoz@intel.com>

obs-packaging/build_all.sh

@@ -10,7 +10,6 @@ set -o errexit
 set -o nounset
 set -o pipefail
 
-
 script_dir=$(dirname "$0")
 #Note:Lets update qemu and the kernel first, they take longer to build.
 #Note: runtime is build at the end to get the version from all its dependencies.
@@ -36,10 +35,22 @@ export BUILD_DISTROS=${BUILD_DISTROS:-xUbuntu_16.04}
 export AUTHOR="${AUTHOR:-user}"
 export AUTHOR_EMAIL="${AUTHOR_EMAIL:-user@example.com}"
 
-cd "$script_dir"
-
 OBS_API="https://api.opensuse.org"
 
+usage() {
+	msg="${1:-}"
+	exit_code=$"${2:-0}"
+	cat <<EOT
+${msg}
+Usage:
+${script_name} <kata-branch>
+EOT
+	exit "${exit_code}"
+}
+
+main() {
+	local branch="${1:-}"
+	[ -n "${branch}" ] || usage "missing branch" "1"
 	if [ -n "${OBS_USER:-}" ] && [ -n "${OBS_PASS:-}" ] && [ ! -e "${OSCRC:-}" ]; then
 		echo "Creating  ${OSCRC} with user $OBS_USER"
 		cat <<eom >"${OSCRC}"
@@ -51,17 +62,21 @@ pass = ${OBS_PASS}
 eom
 	fi
 
-if [ -n "${PUSH}" ]; then
-	# push to obs
-	PUSH_TO_OBS="-p"
-elif [ -n "${LOCAL}" ]; then
-	# local build
-	PUSH_TO_OBS="-l"
-fi
-
 	for p in "${projects[@]}"; do
 		pushd "$p" >>/dev/null
+		update_cmd="./update.sh"
+		if [ -n "${PUSH}" ]; then
+			# push to obs
+			update_cmd+=" -p"
+		elif [ -n "${LOCAL}" ]; then
+			# local build
+			update_cmd+=" -l"
+		fi
+
 		echo "update ${p}"
-	bash ./update.sh "${PUSH_TO_OBS}" -v
+		bash -c "${update_cmd} ${branch}"
 		popd >>/dev/null
 	done
+}
+
+main $@