buildsys: abi-generate: add usage output

Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>

diff --git a/debian/scripts/abi-generate b/debian/scripts/abi-generate
index 44704fb598ebd1fc6c3341bb15d143578c7d400e..a4df443ba643e2871987a965ce44f3d42a100bda 100755 (executable)
--- a/debian/scripts/abi-generate
+++ b/debian/scripts/abi-generate
@@ -4,9 +4,13 @@ use PVE::Tools;
 
 use IO::File;
 
-my $input_file = shift;
-my $output_file = shift;
-my $abi = shift;
+sub usage {
+    die "USAGE: $0 INFILE OUTFILE ABI [INFILE-IS-DEB]\n";
+}
+
+my $input_file = shift // usage();
+my $output_file = shift // usage();
+my $abi = shift // usage();
 my $extract_deb = shift;
 
 die "input file '$input_file' does not exist\n" if ! -e $input_file;