fold.c revision 200462
1106686Stjr/*- 2128005Stjr * Copyright (c) 1990, 1993 3106686Stjr * The Regents of the University of California. All rights reserved. 4106686Stjr * 5106686Stjr * This code is derived from software contributed to Berkeley by 6106686Stjr * Kevin Ruddy. 7106686Stjr * 8106686Stjr * Redistribution and use in source and binary forms, with or without 9106686Stjr * modification, are permitted provided that the following conditions 10106686Stjr * are met: 11106686Stjr * 1. Redistributions of source code must retain the above copyright 12106686Stjr * notice, this list of conditions and the following disclaimer. 13106686Stjr * 2. Redistributions in binary form must reproduce the above copyright 14106686Stjr * notice, this list of conditions and the following disclaimer in the 15106686Stjr * documentation and/or other materials provided with the distribution. 16106686Stjr * 3. All advertising materials mentioning features or use of this software 17106686Stjr * must display the following acknowledgement: 18106686Stjr * This product includes software developed by the University of 19106686Stjr * California, Berkeley and its contributors. 20106686Stjr * 4. Neither the name of the University nor the names of its contributors 21106686Stjr * may be used to endorse or promote products derived from this software 22106686Stjr * without specific prior written permission. 23106686Stjr * 24106686Stjr * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25106686Stjr * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26106686Stjr * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27106686Stjr * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28106686Stjr * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29106686Stjr * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30106686Stjr * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31106686Stjr * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32106686Stjr * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33106686Stjr * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34106686Stjr * SUCH DAMAGE. 35106686Stjr */ 36106686Stjr 37106686Stjr#ifndef lint 38106686Stjrstatic const char copyright[] = 39106686Stjr"@(#) Copyright (c) 1990, 1993\n\ 40106686Stjr The Regents of the University of California. All rights reserved.\n"; 41106686Stjr#endif /* not lint */ 42106686Stjr 43106686Stjr#ifndef lint 44106686Stjr#if 0 45106686Stjrstatic char sccsid[] = "@(#)fold.c 8.1 (Berkeley) 6/6/93"; 46106686Stjr#endif 47106686Stjr#endif /* not lint */ 48106686Stjr 49106686Stjr#include <sys/cdefs.h> 50106686Stjr__FBSDID("$FreeBSD: head/usr.bin/fold/fold.c 200462 2009-12-13 03:14:06Z delphij $"); 51106686Stjr 52106686Stjr#include <err.h> 53106686Stjr#include <limits.h> 54106686Stjr#include <locale.h> 55106686Stjr#include <stdio.h> 56137587Snik#include <stdlib.h> 57137587Snik#include <string.h> 58106686Stjr#include <unistd.h> 59106686Stjr#include <wchar.h> 60106686Stjr#include <wctype.h> 61106686Stjr 62106686Stjr#define DEFLINEWIDTH 80 63106686Stjr 64106686Stjrvoid fold(int); 65106686Stjrstatic int newpos(int, wint_t); 66106686Stjrstatic void usage(void); 67106686Stjr 68106686Stjrint bflag; /* Count bytes, not columns */ 69106686Stjrint sflag; /* Split on word boundaries */ 70106686Stjr 71106686Stjrint 72106686Stjrmain(int argc, char **argv) 73106686Stjr{ 74106686Stjr int ch; 75106686Stjr int rval, width; 76106686Stjr char *p; 77106686Stjr 78106686Stjr (void) setlocale(LC_CTYPE, ""); 79128005Stjr 80106686Stjr width = -1; 81106686Stjr while ((ch = getopt(argc, argv, "0123456789bsw:")) != -1) 82106686Stjr switch (ch) { 83106686Stjr case 'b': 84106686Stjr bflag = 1; 85106686Stjr break; 86106686Stjr case 's': 87106686Stjr sflag = 1; 88106686Stjr break; 89106686Stjr case 'w': 90106686Stjr if ((width = atoi(optarg)) <= 0) { 91106686Stjr errx(1, "illegal width value"); 92106686Stjr } 93106686Stjr break; 94106686Stjr case '0': case '1': case '2': case '3': case '4': 95106686Stjr case '5': case '6': case '7': case '8': case '9': 96106686Stjr if (width == -1) { 97106686Stjr p = argv[optind - 1]; 98106686Stjr if (p[0] == '-' && p[1] == ch && !p[2]) 99106686Stjr width = atoi(++p); 100106686Stjr else 101106686Stjr width = atoi(argv[optind] + 1); 102106686Stjr } 103106686Stjr break; 104106686Stjr default: 105128005Stjr usage(); 106106686Stjr } 107106686Stjr argv += optind; 108106686Stjr argc -= optind; 109106686Stjr 110106686Stjr if (width == -1) 111106686Stjr width = DEFLINEWIDTH; 112106686Stjr rval = 0; 113106686Stjr if (!*argv) 114128005Stjr fold(width); 115106686Stjr else for (; *argv; ++argv) 116106686Stjr if (!freopen(*argv, "r", stdin)) { 117106686Stjr warn("%s", *argv); 118106686Stjr rval = 1; 119106686Stjr } else 120106686Stjr fold(width); 121137587Snik exit(rval); 122106686Stjr} 123106686Stjr 124106686Stjrstatic void 125usage(void) 126{ 127 (void)fprintf(stderr, "usage: fold [-bs] [-w width] [file ...]\n"); 128 exit(1); 129} 130 131/* 132 * Fold the contents of standard input to fit within WIDTH columns (or bytes) 133 * and write to standard output. 134 * 135 * If sflag is set, split the line at the last space character on the line. 136 * This flag necessitates storing the line in a buffer until the current 137 * column > width, or a newline or EOF is read. 138 * 139 * The buffer can grow larger than WIDTH due to backspaces and carriage 140 * returns embedded in the input stream. 141 */ 142void 143fold(int width) 144{ 145 static wchar_t *buf; 146 static int buf_max; 147 int col, i, indx, space; 148 wint_t ch; 149 150 col = indx = 0; 151 while ((ch = getwchar()) != WEOF) { 152 if (ch == '\n') { 153 wprintf(L"%.*ls\n", indx, buf); 154 col = indx = 0; 155 continue; 156 } 157 if ((col = newpos(col, ch)) > width) { 158 if (sflag) { 159 i = indx; 160 while (--i >= 0 && !iswblank(buf[i])) 161 ; 162 space = i; 163 } 164 if (sflag && space != -1) { 165 space++; 166 wprintf(L"%.*ls\n", space, buf); 167 wmemmove(buf, buf + space, indx - space); 168 indx -= space; 169 col = 0; 170 for (i = 0; i < indx; i++) 171 col = newpos(col, buf[i]); 172 } else { 173 wprintf(L"%.*ls\n", indx, buf); 174 col = indx = 0; 175 } 176 col = newpos(col, ch); 177 } 178 if (indx + 1 > buf_max) { 179 buf_max += LINE_MAX; 180 buf = realloc(buf, sizeof(*buf) * buf_max); 181 if (buf == NULL) 182 err(1, "realloc()"); 183 } 184 buf[indx++] = ch; 185 } 186 187 if (indx != 0) 188 wprintf(L"%.*ls", indx, buf); 189} 190 191/* 192 * Update the current column position for a character. 193 */ 194static int 195newpos(int col, wint_t ch) 196{ 197 char buf[MB_LEN_MAX]; 198 size_t len; 199 int w; 200 201 if (bflag) { 202 len = wcrtomb(buf, ch, NULL); 203 col += len; 204 } else 205 switch (ch) { 206 case '\b': 207 if (col > 0) 208 --col; 209 break; 210 case '\r': 211 col = 0; 212 break; 213 case '\t': 214 col = (col + 8) & ~7; 215 break; 216 default: 217 if ((w = wcwidth(ch)) > 0) 218 col += w; 219 break; 220 } 221 222 return (col); 223} 224