1 /* $NetBSD: foldit.c,v 1.7 2009/02/10 23:06:31 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 1990, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 #ifndef lint 34 #if 0 35 static char sccsid[] = "@(#)foldit.c 8.1 (Berkeley) 6/6/93"; 36 #endif 37 __RCSID("$NetBSD: foldit.c,v 1.7 2009/02/10 23:06:31 christos Exp $"); 38 #endif /* not lint */ 39 40 #include <stdio.h> 41 #include <vis.h> 42 #include "extern.h" 43 44 int 45 foldit(const char *chunk, int col, int max, int flags) 46 { 47 const char *cp; 48 49 /* 50 * Keep track of column position. Insert hidden newline 51 * if this chunk puts us over the limit. 52 */ 53 again: 54 cp = chunk; 55 while (*cp) { 56 switch(*cp) { 57 case '\n': 58 case '\r': 59 col = 0; 60 break; 61 case '\t': 62 col = (col + 8) &~ 07; 63 break; 64 case '\b': 65 col = col ? col - 1 : 0; 66 break; 67 default: 68 col++; 69 } 70 if (col > (max - 2)) { 71 printf(flags & VIS_MIMESTYLE ? "=\n" : "\\\n"); 72 col = 0; 73 goto again; 74 } 75 cp++; 76 } 77 return (col); 78 } 79