1 files changed, 38 insertions, 0 deletions
diff --git a/resolv/ns_samename.c b/resolv/ns_samename.c
new file mode 100644
index 0000000000..61fe3cab43
--- /dev/null
+++ b/resolv/ns_samename.c
@@ -0,0 +1,38 @@
+/* Check if two domain names are equal after trailing dot normalization.
+ * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (c) 1995,1999 by Internet Software Consortium.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
+ * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
+ * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
+ * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
+ * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
+ * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
+ * SOFTWARE.
+ */
+
+#include <arpa/nameser.h>
+#include <string.h>
+
+/* Determines whether domain name A is the same as domain name B.
+   Returns -1 on error, 0 if names differ, 1 if names are the
+   same.  */
+int
+__libc_ns_samename (const char *a, const char *b)
+{
+  char ta[NS_MAXDNAME], tb[NS_MAXDNAME];
+
+  if (__libc_ns_makecanon (a, ta, sizeof ta) < 0 ||
+      __libc_ns_makecanon (b, tb, sizeof tb) < 0)
+    return -1;
+  if (__strcasecmp (ta, tb) == 0)
+    return 1;
+  else
+    return 0;
+}
+libc_hidden_def (__libc_ns_samename)