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 1.3 2003/10/04 20:36:44 hmp 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(int argc, char **argv) 62 { 63 register int ch; 64 int rval, width; 65 char *p; 66 67 (void) setlocale(LC_CTYPE, ""); 68 69 width = -1; 70 while ((ch = getopt(argc, argv, "0123456789bsw:")) != -1) 71 switch (ch) { 72 case 'b': 73 bflag = 1; 74 break; 75 case 's': 76 sflag = 1; 77 break; 78 case 'w': 79 if ((width = atoi(optarg)) <= 0) { 80 errx(1, "illegal width value"); 81 } 82 break; 83 case '0': case '1': case '2': case '3': case '4': 84 case '5': case '6': case '7': case '8': case '9': 85 if (width == -1) { 86 p = argv[optind - 1]; 87 if (p[0] == '-' && p[1] == ch && !p[2]) 88 width = atoi(++p); 89 else 90 width = atoi(argv[optind] + 1); 91 } 92 break; 93 default: 94 usage(); 95 } 96 argv += optind; 97 argc -= optind; 98 99 if (width == -1) 100 width = DEFLINEWIDTH; 101 rval = 0; 102 if (!*argv) 103 fold(width); 104 else for (; *argv; ++argv) 105 if (!freopen(*argv, "r", stdin)) { 106 warn("%s", *argv); 107 rval = 1; 108 } else 109 fold(width); 110 exit(rval); 111 } 112 113 static void 114 usage(void) 115 { 116 (void)fprintf(stderr, "usage: fold [-bs] [-w width] [file ...]\n"); 117 exit(1); 118 } 119 120 /* 121 * Fold the contents of standard input to fit within WIDTH columns (or bytes) 122 * and write to standard output. 123 * 124 * If sflag is set, split the line at the last space character on the line. 125 * This flag necessitates storing the line in a buffer until the current 126 * column > width, or a newline or EOF is read. 127 * 128 * The buffer can grow larger than WIDTH due to backspaces and carriage 129 * returns embedded in the input stream. 130 */ 131 void 132 fold(register int width) 133 { 134 static char *buf; 135 static int buf_max; 136 int ch, col, i, indx, space; 137 138 col = indx = 0; 139 while ((ch = getchar()) != EOF) { 140 if (ch == '\n') { 141 if (indx != 0) 142 fwrite(buf, 1, indx, stdout); 143 putchar('\n'); 144 col = indx = 0; 145 continue; 146 } 147 if ((col = newpos(col, ch)) > width) { 148 if (sflag) { 149 i = indx; 150 while (--i >= 0 && !isblank((unsigned char)buf[i])) 151 ; 152 space = i; 153 } 154 if (sflag && space != -1) { 155 space++; 156 fwrite(buf, 1, space, stdout); 157 memmove(buf, buf + space, indx - space); 158 indx -= space; 159 col = 0; 160 for (i = 0; i < indx; i++) 161 col = newpos(col, 162 (unsigned char)buf[i]); 163 } else { 164 fwrite(buf, 1, indx, stdout); 165 col = indx = 0; 166 } 167 putchar('\n'); 168 col = newpos(col, ch); 169 } 170 if (indx + 1 > buf_max) { 171 buf_max += LINE_MAX; 172 if ((buf = realloc(buf, buf_max)) == NULL) 173 err(1, "realloc()"); 174 } 175 buf[indx++] = ch; 176 } 177 178 if (indx != 0) 179 fwrite(buf, 1, indx, stdout); 180 } 181 182 /* 183 * Update the current column position for a character. 184 */ 185 static int 186 newpos(int col, int ch) 187 { 188 189 if (bflag) 190 ++col; 191 else 192 switch (ch) { 193 case '\b': 194 if (col > 0) 195 --col; 196 break; 197 case '\r': 198 col = 0; 199 break; 200 case '\t': 201 col = (col + 8) & ~7; 202 break; 203 default: 204 if (isprint(ch)) 205 ++col; 206 break; 207 } 208 209 return (col); 210 } 211