Moved hash.c from libdhcp to libomapi, in anticipation of moving the

tsig_key structure into libomapi.  (tsig_keys are stored in a hashtable,
and libomapi should not depend on libdhcp.)

includes/omapip/hash.h

@@ -0,0 +1,141 @@
+/* hash.h
+
+   Definitions for hashing... */
+
+/*
+ * Copyright (c) 1995-2000 Internet Software Consortium.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of The Internet Software Consortium nor the names
+ *    of its contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE INTERNET SOFTWARE CONSORTIUM AND
+ * CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE INTERNET SOFTWARE CONSORTIUM OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * This software has been written for the Internet Software Consortium
+ * by Ted Lemon in cooperation with Vixie Enterprises and Nominum, Inc.
+ * To learn more about the Internet Software Consortium, see
+ * ``http://www.isc.org/''.  To learn more about Vixie Enterprises,
+ * see ``http://www.vix.com''.   To learn more about Nominum, Inc., see
+ * ``http://www.nominum.com''.
+ */
+
+#ifndef OMAPI_HASH_H
+#define OMAPI_HASH_H
+
+#define DEFAULT_HASH_SIZE	9973
+
+/* The purpose of the hashed_object_t struct is to not match anything else. */
+typedef struct {
+	int foo;
+} hashed_object_t;
+
+typedef void (*hash_foreach_func) (const unsigned char *,
+				   unsigned, hashed_object_t *);
+typedef int (*hash_reference) (hashed_object_t **, hashed_object_t *,
+			       const char *, int);
+typedef int (*hash_dereference) (hashed_object_t **, const char *, int);
+
+struct hash_bucket {
+	struct hash_bucket *next;
+	const unsigned char *name;
+	unsigned len;
+	hashed_object_t *value;
+};
+
+typedef int (*hash_comparator_t)(const void *, const void *, unsigned long);
+
+struct hash_table {
+	unsigned hash_count;
+	struct hash_bucket *buckets [DEFAULT_HASH_SIZE];
+	hash_reference referencer;
+	hash_dereference dereferencer;
+	hash_comparator_t cmp;
+	int (*do_hash) (const unsigned char *, unsigned, unsigned);
+};
+
+struct named_hash {
+	struct named_hash *next;
+	const char *name;
+	struct hash_table *hash;
+};
+
+#define HASH_FUNCTIONS_DECL(name, bufarg, type)				      \
+void name##_hash_add (struct hash_table *, bufarg, unsigned, type *,	      \
+		      const char *, int);				      \
+void name##_hash_delete (struct hash_table *, bufarg, unsigned,		      \
+			 const char *, int);				      \
+int name##_hash_lookup (type **, struct hash_table *, bufarg, unsigned,	      \
+			const char *, int);				      \
+int name##_hash_foreach (struct hash_table *,				      \
+			 void (*) (bufarg, unsigned, type *));
+
+
+#define HASH_FUNCTIONS(name, bufarg, type)				      \
+void name##_hash_add (struct hash_table *table,				      \
+		      bufarg buf, unsigned len, type *ptr,		      \
+		      const char *file, int line)			      \
+{									      \
+	add_hash (table,						      \
+		  (const unsigned char *)buf,				      \
+		  len, (hashed_object_t *)ptr, file, line);		      \
+}									      \
+									      \
+void name##_hash_delete (struct hash_table *table,			      \
+			 bufarg buf, unsigned len, const char *file, int line)\
+{									      \
+	delete_hash_entry (table, (const unsigned char *)buf,		      \
+			   len, file, line);				      \
+}									      \
+									      \
+int name##_hash_lookup (type **ptr, struct hash_table *table,		      \
+			bufarg buf, unsigned len, const char *file, int line) \
+{									      \
+	return hash_lookup ((hashed_object_t **)ptr, table,		      \
+			    (const unsigned char *)buf, len, file, line);     \
+}									      \
+									      \
+int name##_hash_foreach (struct hash_table *table,			      \
+			 void (*func) (bufarg, unsigned, type *))	      \
+{									      \
+	return hash_foreach (table, (hash_foreach_func)func);		      \
+}
+
+
+struct hash_table *new_hash_table (int, const char *, int);
+void free_hash_table (struct hash_table *, const char *, int);
+struct hash_bucket *new_hash_bucket (const char *, int);
+void free_hash_bucket (struct hash_bucket *, const char *, int);
+struct hash_table *new_hash (hash_reference, hash_dereference, int);
+void add_hash (struct hash_table *,
+		      const unsigned char *, unsigned, hashed_object_t *,
+		      const char *, int);
+void delete_hash_entry (struct hash_table *, const unsigned char *,
+			       unsigned, const char *, int);
+int hash_lookup (hashed_object_t **, struct hash_table *,
+			const unsigned char *, unsigned, const char *, int);
+int hash_foreach (struct hash_table *, hash_foreach_func);
+int casecmp (const void *s, const void *t, unsigned long len);
+
+#endif /* OMAPI_HASH_H */