+/*
+ * Emit a warning and return true iff ref1 and ref2 have the same name
+ * and the same sha1. Die if they have the same name but different
+ * sha1s.
+ */
+static int is_dup_ref(const struct ref_entry *ref1, const struct ref_entry *ref2)
+{
+ if (!strcmp(ref1->name, ref2->name)) {
+ /* Duplicate name; make sure that the SHA1s match: */
+ if (hashcmp(ref1->sha1, ref2->sha1))
+ die("Duplicated ref, and SHA1s don't match: %s",
+ ref1->name);
+ warning("Duplicated ref: %s", ref1->name);
+ return 1;
+ } else {
+ return 0;
+ }
+}
+