1 files changed, 71 insertions, 0 deletions
diff --git a/src/usr.bin/vis/foldit.c b/src/usr.bin/vis/foldit.c
new file mode 100644
index 0000000..f9abd99
--- /dev/null
+++ b/src/usr.bin/vis/foldit.c
@@ -0,0 +1,71 @@
+/*	$OpenBSD: foldit.c,v 1.7 2013/11/12 22:51:18 deraadt Exp $	*/
+/*	$NetBSD: foldit.c,v 1.4 1994/12/20 16:13:02 jtc Exp $	*/
+
+/*-
+ * Copyright (c) 1990, 1993
+ *	The Regents of the University of California.  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 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.
+ */
+
+#include <stdio.h>
+
+int	foldit(char *chunk, int col, int max);
+
+int
+foldit(char *chunk, int col, int max)
+{
+	char *cp;
+
+	/*
+	 * Keep track of column position. Insert hidden newline
+	 * if this chunk puts us over the limit.
+	 */
+again:
+	cp = chunk;
+	while (*cp) {
+		switch(*cp) {
+		case '\n':
+		case '\r':
+			col = 0;
+			break;
+		case '\t':
+			col = (col + 8) & ~07;
+			break;
+		case '\b':
+			col = col ? col - 1 : 0;
+			break;
+		default:
+			col++;
+		}
+		if (col > (max - 2)) {
+			printf("\\\n");
+			col = 0;
+			goto again;
+		} 
+		cp++;
+	}
+	return (col);
+}