Disallow the empty string as an attribute name

mhagger · gitster · commit c0b13b21b8da · 2011-08-04T15:53:15.000-07:00
Previously, it was possible to have a line like "file.txt =foo" in a
.gitattribute file, after which an invocation like "git check-attr ''
-- file.txt" would succeed.  This patch disallows both constructs.

Please note that any existing .gitattributes file that tries to set an
empty attribute will now trigger the error message "error: : not a
valid attribute name" whereas previously the nonsense was allowed
through.

Signed-off-by: Michael Haggerty &lt;mhagger@alum.mit.edu&gt;
Signed-off-by: Junio C Hamano &lt;gitster@pobox.com&gt;
diff --git a/attr.c b/attr.c
@@ -53,7 +53,7 @@ static int invalid_attr_name(const char *name, int namelen)
 	 * Attribute name cannot begin with '-' and must consist of
 	 * characters from [-A-Za-z0-9_.].
 	 */
-	if (*name == '-')
+	if (namelen <= 0 || *name == '-')
 		return -1;
 	while (namelen--) {
 		char ch = *name++;
diff --git a/t/t0003-attributes.sh b/t/t0003-attributes.sh
@@ -42,6 +42,12 @@ test_expect_success 'setup' '
 
 '
 
+test_expect_success 'command line checks' '
+
+	test_must_fail git check-attr "" -- f
+
+'
+
 test_expect_success 'attribute test' '
 
 	attr_check f f &&
