1 files changed, 151 insertions, 0 deletions
diff --git a/usr.bin/m4/look.c b/usr.bin/m4/look.c
new file mode 100644
index 000000000000..ffb58e05167c
--- /dev/null
+++ b/usr.bin/m4/look.c
@@ -0,0 +1,151 @@
+/*	$OpenBSD: look.c,v 1.9 2002/02/16 21:27:48 millert Exp $	*/
+
+/*
+ * Copyright (c) 1989, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Ozan Yigit at York University.
+ *
+ * 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. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University 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 REGENTS 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 REGENTS 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.
+ */
+
+#ifndef lint
+static char sccsid[] = "@(#)look.c	8.1 (Berkeley) 6/6/93";
+#endif /* not lint */
+
+/*
+ * look.c
+ * Facility: m4 macro processor
+ * by: oz
+ */
+
+#include <sys/types.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <string.h>
+#include "mdef.h"
+#include "stdd.h"
+#include "extern.h"
+
+static void freent(ndptr);
+
+unsigned
+hash(name)
+	const char *name;
+{
+	unsigned int h = 0;
+	while (*name)
+		h = (h << 5) + h + *name++;
+	return (h);
+}
+
+/*
+ * find name in the hash table
+ */
+ndptr 
+lookup(name)
+	const char *name;
+{
+	ndptr p;
+	unsigned int h;
+
+	h = hash(name);
+	for (p = hashtab[h % HASHSIZE]; p != nil; p = p->nxtptr)
+		if (h == p->hv && STREQ(name, p->name))
+			break;
+	return (p);
+}
+
+/*
+ * hash and create an entry in the hash table.
+ * The new entry is added in front of a hash bucket.
+ */
+ndptr 
+addent(name)
+	const char *name;
+{
+	unsigned int h;
+	ndptr p;
+
+	h = hash(name);
+	p = (ndptr) xalloc(sizeof(struct ndblock));
+	p->nxtptr = hashtab[h % HASHSIZE];
+	hashtab[h % HASHSIZE] = p;
+	p->name = xstrdup(name);
+	p->hv = h;
+	return p;
+}
+
+static void
+freent(p)
+	ndptr p;
+{
+	free((char *) p->name);
+	if (p->defn != null)
+		free((char *) p->defn);
+	free((char *) p);
+}
+
+/*
+ * remove an entry from the hashtable
+ */
+void
+remhash(name, all)
+	const char *name;
+	int all;
+{
+	unsigned int h;
+	ndptr xp, tp, mp;
+
+	h = hash(name);
+	mp = hashtab[h % HASHSIZE];
+	tp = nil;
+	while (mp != nil) {
+		if (mp->hv == h && STREQ(mp->name, name)) {
+			mp = mp->nxtptr;
+			if (tp == nil) {
+				freent(hashtab[h % HASHSIZE]);
+				hashtab[h % HASHSIZE] = mp;
+			}
+			else {
+				xp = tp->nxtptr;
+				tp->nxtptr = mp;
+				freent(xp);
+			}
+			if (!all)
+				break;
+		}
+		else {
+			tp = mp;
+			mp = mp->nxtptr;
+		}
+	}
+}