external_deps: rework the help and error messages, also fix a bug

Author: illwieckz

external_deps/build.sh

@@ -1471,7 +1471,7 @@ all_windows_platforms='windows-amd64-mingw windows-amd64-msvc windows-i686-mingw
 all_macos_platforms='macos-amd64-default'
 all_platforms="${all_linux_platforms} ${all_windows_platforms} ${all_macos_platforms}"
 
-errorHelp() {
+printHelp() {
 	sed -e 's/\\t/\t/g' <<-EOF
 	usage: $(basename "${BASH_SOURCE[0]}") [OPTION] <PLATFORM> <PACKAGE[S]...>
 
@@ -1530,7 +1530,8 @@ errorHelp() {
 	\tall\t${all_linux_arm64_default_packages}
 
 	EOF
-	false
+	
+	exit
 }
 
 download_only='false'
@@ -1551,17 +1552,22 @@ do
 		require_theirs='true'
 		shift
 	;;
-	'--'*)
-		helpError
+	'-h'|'--help')
+		printHelp
+	;;
+	'-'*)
+		log ERROR 'Unknown option'
 	;;
 	*)
 		break
 	esac
 done
 
 # Usage
-if [ "${#}" -lt "2" ]; then
-	errorHelp
+if [ "${#}" -lt "1" ]; then
+	log ERROR 'Missing platform and package'
+elif [ "${#}" -lt "2" ]; then
+	log ERROR 'Missing package'
 fi
 
 # Do not reuse self-built curl from external_deps custom PATH