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