sbopkglint: refactor gzip detection.

1 files changed, 6 insertions, 0 deletions

diff --git a/sbopkglint b/sbopkglint
index fd458c4..2e86174 100755
--- a/sbopkglint
+++ b/sbopkglint
@@ -584,6 +584,12 @@ find_warnfiles() {
 	rm -f $output
 }
 
+# return true if the file is gzipped, otherwise false.
+# faster than using file(1).
+is_gzipped() {
+	[ "$( hexdump -n 2 -e '"%2x"' "$1" )" = '8b1f' ]
+}
+
 # N.B. these need to match the template (and they do)
 TMP=${TMP:-/tmp/SBo}
 OUTPUT=${OUTPUT:-/tmp}