Add ohash_* functions to libc.

Ok'd deraadt@, millert@

src/include/Makefile

@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile,v 1.88 2000/12/18 16:51:49 brad Exp $
+#	$OpenBSD: Makefile,v 1.89 2001/03/02 13:27:04 espie Exp $
 #	$NetBSD: Makefile,v 1.59 1996/05/15 21:36:43 jtc Exp $
 
 #	@(#)Makefile	5.45.1.1 (Berkeley) 5/6/91
@@ -13,7 +13,8 @@ FILES=	a.out.h ar.h assert.h bitstring.h blf.h bm.h bsd_auth.h cast.h cpio.h \
 	fnmatch.h fstab.h fts.h glob.h grp.h ifaddrs.h inttypes.h \
 	iso646.h kvm.h langinfo.h libgen.h limits.h locale.h login_cap.h \
 	malloc.h math.h md4.h md5.h memory.h mpool.h ndbm.h netdb.h netgroup.h \
-	nlist.h nl_types.h olf_abi.h paths.h poll.h pwd.h ranlib.h re_comp.h \
+	nlist.h nl_types.h ohash.h olf_abi.h paths.h poll.h pwd.h \
+	ranlib.h re_comp.h \
 	readpassphrase.h regex.h resolv.h rmd160.h search.h setjmp.h sgtty.h \
 	sha1.h skipjack.h signal.h stab.h stdbool.h stddef.h stdio.h stdlib.h \
 	string.h strings.h struct.h sysexits.h tar.h time.h ttyent.h tzfile.h \

src/include/ohash.h

@@ -0,0 +1,85 @@
+#ifndef OHASH_H
+#define OHASH_H
+/* $OpenBSD: ohash.h,v 1.1 2001/03/02 13:27:05 espie Exp $ */
+/* ex:ts=8 sw=4: 
+ */
+
+/*
+ * Copyright (c) 1999 Marc Espie.
+ *
+ * Code written for the OpenBSD project.
+ * 
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE OPENBSD PROJECT 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 OPENBSD
+ * PROJECT 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.
+ */
+
+/* Open hashing support. 
+ * Open hashing was chosen because it is much lighter than other hash
+ * techniques, and more efficient in most cases.
+ */
+
+struct ohash_info {
+	ptrdiff_t key_offset;
+	void *data;	/* user data */
+	void *(*halloc) __P((size_t, void *));
+	void (*hfree) __P((void *, size_t, void *));
+	void *(*alloc) __P((size_t, void *));
+};
+
+struct _ohash_record;
+
+struct ohash {
+	struct _ohash_record 	*t;
+	struct ohash_info 	info;
+	unsigned int 		size;
+	unsigned int 		total;
+	unsigned int 		deleted;
+};
+
+/* For this to be tweakable, we use small primitives, and leave part of the
+ * logic to the client application.  e.g., hashing is left to the client
+ * application.  We also provide a simple table entry lookup that yields
+ * a hashing table index (opaque) to be used in find/insert/remove.
+ * The keys are stored at a known position in the client data.
+ */
+__BEGIN_DECLS
+void ohash_init __P((struct ohash *, unsigned, struct ohash_info *));
+void ohash_delete __P((struct ohash *));
+
+unsigned int ohash_lookup_string __P((struct ohash *, const char *, u_int32_t));
+unsigned int ohash_lookup_interval __P((struct ohash *, const char *, \
+	const char *, u_int32_t));
+unsigned int ohash_lookup_memory __P((struct ohash *, const char *, \
+	size_t, u_int32_t));
+void *ohash_find __P((struct ohash *, unsigned int));
+void *ohash_remove __P((struct ohash *, unsigned int));
+void *ohash_insert __P((struct ohash *, unsigned int, void *));
+void *ohash_first __P((struct ohash *, unsigned int *));
+void *ohash_next __P((struct ohash *, unsigned int *));
+unsigned int ohash_entries __P((struct ohash *));
+
+void *ohash_create_entry __P((struct ohash_info *, const char *, const char **));
+u_int32_t ohash_interval __P((const char *, const char **));
+
+unsigned int ohash_qlookupi __P((struct ohash *, const char *, const char **));
+unsigned int ohash_qlookup __P((struct ohash *, const char *));
+__END_DECLS
+#endif