1 /*- 2 * Copyright (c) 1990, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Kevin Ruddy. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#) Copyright (c) 1990, 1993 The Regents of the University of California. All rights reserved. 37 * @(#)fold.c 8.1 (Berkeley) 6/6/93 38 * $FreeBSD: src/usr.bin/fold/fold.c,v 1.4.2.3 2002/07/11 01:01:44 tjr Exp $ 39 * $DragonFly: src/usr.bin/fold/fold.c,v 1.2 2003/06/17 04:29:26 dillon Exp $ 40 */ 41 42 #include <ctype.h> 43 #include <err.h> 44 #include <limits.h> 45 #include <locale.h> 46 #include <stdio.h> 47 #include <stdlib.h> 48 #include <string.h> 49 #include <unistd.h> 50 51 #define DEFLINEWIDTH 80 52 53 void fold(int); 54 static int newpos(int, int); 55 static void usage(void); 56 57 int bflag; /* Count bytes, not columns */ 58 int sflag; /* Split on word boundaries */ 59 60 int 61 main(argc, argv) 62 int argc; 63 char **argv; 64 { 65 register int ch; 66 int rval, width; 67 char *p; 68 69 (void) setlocale(LC_CTYPE, ""); 70 71 width = -1; 72 while ((ch = getopt(argc, argv, "0123456789bsw:")) != -1) 73 switch (ch) { 74 case 'b': 75 bflag = 1; 76 break; 77 case 's': 78 sflag = 1; 79 break; 80 case 'w': 81 if ((width = atoi(optarg)) <= 0) { 82 errx(1, "illegal width value"); 83 } 84 break; 85 case '0': case '1': case '2': case '3': case '4': 86 case '5': case '6': case '7': case '8': case '9': 87 if (width == -1) { 88 p = argv[optind - 1]; 89 if (p[0] == '-' && p[1] == ch && !p[2]) 90 width = atoi(++p); 91 else 92 width = atoi(argv[optind] + 1); 93 } 94 break; 95 default: 96 usage(); 97 } 98 argv += optind; 99 argc -= optind; 100 101 if (width == -1) 102 width = DEFLINEWIDTH; 103 rval = 0; 104 if (!*argv) 105 fold(width); 106 else for (; *argv; ++argv) 107 if (!freopen(*argv, "r", stdin)) { 108 warn("%s", *argv); 109 rval = 1; 110 } else 111 fold(width); 112 exit(rval); 113 } 114 115 static void 116 usage() 117 { 118 (void)fprintf(stderr, "usage: fold [-bs] [-w width] [file ...]\n"); 119 exit(1); 120 } 121 122 /* 123 * Fold the contents of standard input to fit within WIDTH columns (or bytes) 124 * and write to standard output. 125 * 126 * If sflag is set, split the line at the last space character on the line. 127 * This flag necessitates storing the line in a buffer until the current 128 * column > width, or a newline or EOF is read. 129 * 130 * The buffer can grow larger than WIDTH due to backspaces and carriage 131 * returns embedded in the input stream. 132 */ 133 void 134 fold(width) 135 register int width; 136 { 137 static char *buf; 138 static int buf_max; 139 int ch, col, i, indx, space; 140 141 col = indx = 0; 142 while ((ch = getchar()) != EOF) { 143 if (ch == '\n') { 144 if (indx != 0) 145 fwrite(buf, 1, indx, stdout); 146 putchar('\n'); 147 col = indx = 0; 148 continue; 149 } 150 if ((col = newpos(col, ch)) > width) { 151 if (sflag) { 152 i = indx; 153 while (--i >= 0 && !isblank((unsigned char)buf[i])) 154 ; 155 space = i; 156 } 157 if (sflag && space != -1) { 158 space++; 159 fwrite(buf, 1, space, stdout); 160 memmove(buf, buf + space, indx - space); 161 indx -= space; 162 col = 0; 163 for (i = 0; i < indx; i++) 164 col = newpos(col, 165 (unsigned char)buf[i]); 166 } else { 167 fwrite(buf, 1, indx, stdout); 168 col = indx = 0; 169 } 170 putchar('\n'); 171 col = newpos(col, ch); 172 } 173 if (indx + 1 > buf_max) { 174 buf_max += LINE_MAX; 175 if ((buf = realloc(buf, buf_max)) == NULL) 176 err(1, "realloc()"); 177 } 178 buf[indx++] = ch; 179 } 180 181 if (indx != 0) 182 fwrite(buf, 1, indx, stdout); 183 } 184 185 /* 186 * Update the current column position for a character. 187 */ 188 static int 189 newpos(col, ch) 190 int col, ch; 191 { 192 193 if (bflag) 194 ++col; 195 else 196 switch (ch) { 197 case '\b': 198 if (col > 0) 199 --col; 200 break; 201 case '\r': 202 col = 0; 203 break; 204 case '\t': 205 col = (col + 8) & ~7; 206 break; 207 default: 208 if (isprint(ch)) 209 ++col; 210 break; 211 } 212 213 return (col); 214 } 215