1 /* $NetBSD: fold.c,v 1.7 1997/10/18 15:02:18 lukem Exp $ */ 2 3 /*- 4 * Copyright (c) 1990, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Kevin Ruddy. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 */ 38 39 #include <sys/cdefs.h> 40 #ifndef lint 41 __COPYRIGHT("@(#) Copyright (c) 1990, 1993\n\ 42 The Regents of the University of California. All rights reserved.\n"); 43 #endif /* not lint */ 44 45 #ifndef lint 46 #if 0 47 static char sccsid[] = "@(#)fold.c 8.1 (Berkeley) 6/6/93"; 48 #endif 49 __RCSID("$NetBSD: fold.c,v 1.7 1997/10/18 15:02:18 lukem Exp $"); 50 #endif /* not lint */ 51 52 #include <stdio.h> 53 #include <stdlib.h> 54 #include <string.h> 55 #include <unistd.h> 56 #include <err.h> 57 58 #define DEFLINEWIDTH 80 59 60 int main __P((int, char **)); 61 static void fold __P((int)); 62 static int new_column_position __P((int, int)); 63 64 int count_bytes = 0; 65 int split_words = 0; 66 67 int 68 main(argc, argv) 69 int argc; 70 char **argv; 71 { 72 int ch; 73 int width; 74 char *p; 75 76 width = -1; 77 while ((ch = getopt(argc, argv, "0123456789bsw:")) != -1) 78 switch (ch) { 79 case 'b': 80 count_bytes = 1; 81 break; 82 case 's': 83 split_words = 1; 84 break; 85 case 'w': 86 if ((width = atoi(optarg)) <= 0) { 87 (void)fprintf(stderr, 88 "fold: illegal width value.\n"); 89 exit(1); 90 } 91 break; 92 case '0': case '1': case '2': case '3': case '4': 93 case '5': case '6': case '7': case '8': case '9': 94 if (width == -1) { 95 p = argv[optind - 1]; 96 if (p[0] == '-' && p[1] == ch && !p[2]) 97 width = atoi(++p); 98 else 99 width = atoi(argv[optind] + 1); 100 } 101 break; 102 default: 103 (void)fprintf(stderr, 104 "usage: fold [-bs] [-w width] [file ...]\n"); 105 exit(1); 106 } 107 argv += optind; 108 argc -= optind; 109 110 if (width == -1) 111 width = DEFLINEWIDTH; 112 113 if (!*argv) 114 fold(width); 115 else for (; *argv; ++argv) 116 if (!freopen(*argv, "r", stdin)) { 117 err (1, "%s", *argv); 118 /* NOTREACHED */ 119 } else 120 fold(width); 121 exit(0); 122 } 123 124 /* 125 * Fold the contents of standard input to fit within WIDTH columns 126 * (or bytes) and write to standard output. 127 * 128 * If split_words is set, split the line at the last space character 129 * on the line. This flag necessitates storing the line in a buffer 130 * until the current column > width, or a newline or EOF is read. 131 * 132 * The buffer can grow larger than WIDTH due to backspaces and carriage 133 * returns embedded in the input stream. 134 */ 135 static void 136 fold(width) 137 int width; 138 { 139 static char *buf = NULL; 140 static int buf_max = 0; 141 int ch, col; 142 int indx; 143 144 col = indx = 0; 145 while ((ch = getchar()) != EOF) { 146 if (ch == '\n') { 147 if (indx != 0) 148 fwrite (buf, 1, indx, stdout); 149 putchar('\n'); 150 col = indx = 0; 151 continue; 152 } 153 154 col = new_column_position (col, ch); 155 if (col > width) { 156 int i, last_space; 157 158 if (split_words) { 159 for (i = 0, last_space = -1; i < indx; i++) 160 if(buf[i] == ' ') last_space = i; 161 } 162 163 if (split_words && last_space != -1) { 164 last_space++; 165 166 fwrite (buf, 1, last_space, stdout); 167 memmove (buf, buf+last_space, indx-last_space); 168 169 indx -= last_space; 170 col = 0; 171 for (i = 0; i < indx; i++) { 172 col = new_column_position (col, ch); 173 } 174 } else { 175 fwrite (buf, 1, indx, stdout); 176 col = indx = 0; 177 } 178 putchar('\n'); 179 180 /* calculate the column position for the next line. */ 181 col = new_column_position (col, ch); 182 } 183 184 if (indx + 1 > buf_max) { 185 /* Allocate buffer in LINE_MAX increments */ 186 buf_max += 2048; 187 if((buf = realloc (buf, buf_max)) == NULL) { 188 err (1, "realloc"); 189 /* NOTREACHED */ 190 } 191 } 192 buf[indx++] = ch; 193 } 194 195 if (indx != 0) 196 fwrite (buf, 1, indx, stdout); 197 } 198 199 /* 200 * calculate the column position 201 */ 202 static int 203 new_column_position (col, ch) 204 int col; 205 int ch; 206 { 207 if (!count_bytes) { 208 switch (ch) { 209 case '\b': 210 if (col > 0) 211 --col; 212 break; 213 case '\r': 214 col = 0; 215 break; 216 case '\t': 217 col = (col + 8) & ~7; 218 break; 219 default: 220 ++col; 221 break; 222 } 223 } else { 224 ++col; 225 } 226 227 return col; 228 } 229