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diff --git a/dbm/sdbm/sdbm_hash.c b/dbm/sdbm/sdbm_hash.c
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+/* Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * sdbm - ndbm work-alike hashed database library
+ * based on Per-Aake Larson's Dynamic Hashing algorithms. BIT 18 (1978).
+ * author: oz@nexus.yorku.ca
+ * status: ex-public domain. keep it that way.
+ *
+ * hashing routine
+ */
+
+#include "apr_sdbm.h"
+#include "sdbm_private.h"
+
+/*
+ * polynomial conversion ignoring overflows
+ * [this seems to work remarkably well, in fact better
+ * then the ndbm hash function. Replace at your own risk]
+ * use: 65599 nice.
+ * 65587 even better.
+ */
+long sdbm_hash(const char *str, int len)
+{
+ register unsigned long n = 0;
+
+#define DUFF /* go ahead and use the loop-unrolled version */
+#ifdef DUFF
+
+#define HASHC n = *str++ + 65599 * n
+
+ if (len > 0) {
+ register int loop = (len + 8 - 1) >> 3;
+
+ switch(len & (8 - 1)) {
+ case 0: do {
+ HASHC; case 7: HASHC;
+ case 6: HASHC; case 5: HASHC;
+ case 4: HASHC; case 3: HASHC;
+ case 2: HASHC; case 1: HASHC;
+ } while (--loop);
+ }
+
+ }
+#else
+ while (len--)
+ n = *str++ + 65599 * n;
+#endif
+ return n;
+}