1 /* $NetBSD: fold.c,v 1.11 2000/09/08 12:57:28 mjl 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 1.11 2000/09/08 12:57:28 mjl 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(int, char **); 61 static void fold(int); 62 static int new_column_position(int, int); 63 static void usage(void); 64 65 int count_bytes = 0; 66 int split_words = 0; 67 68 int 69 main(int argc, char **argv) 70 { 71 int ch; 72 int width; 73 char *p; 74 75 width = -1; 76 while ((ch = getopt(argc, argv, "0123456789bsw:")) != -1) 77 switch (ch) { 78 case 'b': 79 count_bytes = 1; 80 break; 81 case 's': 82 split_words = 1; 83 break; 84 case 'w': 85 if ((width = atoi(optarg)) <= 0) 86 errx(1, "illegal width value"); 87 break; 88 case '0': case '1': case '2': case '3': case '4': 89 case '5': case '6': case '7': case '8': case '9': 90 if (width == -1) { 91 p = argv[optind - 1]; 92 if (p[0] == '-' && p[1] == ch && !p[2]) 93 width = atoi(++p); 94 else 95 width = atoi(argv[optind] + 1); 96 } 97 break; 98 default: 99 usage(); 100 } 101 argv += optind; 102 argc -= optind; 103 104 if (width == -1) 105 width = DEFLINEWIDTH; 106 107 if (!*argv) 108 fold(width); 109 else for (; *argv; ++argv) 110 if (!freopen(*argv, "r", stdin)) { 111 err (1, "%s", *argv); 112 /* NOTREACHED */ 113 } else 114 fold(width); 115 exit(0); 116 } 117 118 /* 119 * Fold the contents of standard input to fit within WIDTH columns 120 * (or bytes) and write to standard output. 121 * 122 * If split_words is set, split the line at the last space character 123 * on the line. This flag necessitates storing the line in a buffer 124 * until the current column > width, or a newline or EOF is read. 125 * 126 * The buffer can grow larger than WIDTH due to backspaces and carriage 127 * returns embedded in the input stream. 128 */ 129 static void 130 fold(int width) 131 { 132 static char *buf = NULL; 133 static int buf_max = 0; 134 int ch, col; 135 int indx; 136 137 col = indx = 0; 138 while ((ch = getchar()) != EOF) { 139 if (ch == '\n') { 140 if (indx != 0) 141 fwrite (buf, 1, indx, stdout); 142 putchar('\n'); 143 col = indx = 0; 144 continue; 145 } 146 147 col = new_column_position (col, ch); 148 if (col > width) { 149 int i, last_space; 150 151 #ifdef __GNUC__ 152 last_space = 0; /* XXX gcc */ 153 #endif 154 if (split_words) { 155 for (i = 0, last_space = -1; i < indx; i++) 156 if (buf[i] == ' ') 157 last_space = i; 158 } 159 160 if (split_words && last_space != -1) { 161 last_space++; 162 163 fwrite (buf, 1, last_space, stdout); 164 memmove (buf, buf+last_space, indx-last_space); 165 166 indx -= last_space; 167 col = 0; 168 for (i = 0; i < indx; i++) { 169 col = new_column_position (col, buf[i]); 170 } 171 } else { 172 fwrite (buf, 1, indx, stdout); 173 col = indx = 0; 174 } 175 putchar('\n'); 176 177 /* calculate the column position for the next line. */ 178 col = new_column_position (col, ch); 179 } 180 181 if (indx + 1 > buf_max) { 182 /* Allocate buffer in LINE_MAX increments */ 183 buf_max += 2048; 184 if((buf = realloc (buf, buf_max)) == NULL) { 185 err (1, "realloc"); 186 /* NOTREACHED */ 187 } 188 } 189 buf[indx++] = ch; 190 } 191 192 if (indx != 0) 193 fwrite (buf, 1, indx, stdout); 194 } 195 196 /* 197 * calculate the column position 198 */ 199 static int 200 new_column_position (int col, int ch) 201 { 202 if (!count_bytes) { 203 switch (ch) { 204 case '\b': 205 if (col > 0) 206 --col; 207 break; 208 case '\r': 209 col = 0; 210 break; 211 case '\t': 212 col = (col + 8) & ~7; 213 break; 214 default: 215 ++col; 216 break; 217 } 218 } else { 219 ++col; 220 } 221 222 return col; 223 } 224 225 static void 226 usage(void) 227 { 228 (void)fprintf(stderr, 229 "usage: fold [-bs] [-w width] [file ...]\n"); 230 exit(1); 231 } 232 233