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 37 #ifndef lint 38 static const char copyright[] = 39 "@(#) Copyright (c) 1990, 1993\n\ 40 The Regents of the University of California. All rights reserved.\n"; 41 #endif /* not lint */ 42 43 #ifndef lint 44 #if 0 45 static char sccsid[] = "@(#)fold.c 8.1 (Berkeley) 6/6/93"; 46 #endif 47 #endif /* not lint */ 48 49 #include <sys/cdefs.h> 50 __FBSDID("$FreeBSD: src/usr.bin/fold/fold.c,v 1.4.2.3 2002/07/11 01:01:44 tjr Exp $"); 51 52 #include <ctype.h> 53 #include <err.h> 54 #include <limits.h> 55 #include <locale.h> 56 #include <stdio.h> 57 #include <stdlib.h> 58 #include <string.h> 59 #include <unistd.h> 60 61 #define DEFLINEWIDTH 80 62 63 void fold(int); 64 static int newpos(int, int); 65 static void usage(void); 66 67 int bflag; /* Count bytes, not columns */ 68 int sflag; /* Split on word boundaries */ 69 70 int 71 main(argc, argv) 72 int argc; 73 char **argv; 74 { 75 register int ch; 76 int rval, width; 77 char *p; 78 79 (void) setlocale(LC_CTYPE, ""); 80 81 width = -1; 82 while ((ch = getopt(argc, argv, "0123456789bsw:")) != -1) 83 switch (ch) { 84 case 'b': 85 bflag = 1; 86 break; 87 case 's': 88 sflag = 1; 89 break; 90 case 'w': 91 if ((width = atoi(optarg)) <= 0) { 92 errx(1, "illegal width value"); 93 } 94 break; 95 case '0': case '1': case '2': case '3': case '4': 96 case '5': case '6': case '7': case '8': case '9': 97 if (width == -1) { 98 p = argv[optind - 1]; 99 if (p[0] == '-' && p[1] == ch && !p[2]) 100 width = atoi(++p); 101 else 102 width = atoi(argv[optind] + 1); 103 } 104 break; 105 default: 106 usage(); 107 } 108 argv += optind; 109 argc -= optind; 110 111 if (width == -1) 112 width = DEFLINEWIDTH; 113 rval = 0; 114 if (!*argv) 115 fold(width); 116 else for (; *argv; ++argv) 117 if (!freopen(*argv, "r", stdin)) { 118 warn("%s", *argv); 119 rval = 1; 120 } else 121 fold(width); 122 exit(rval); 123 } 124 125 static void 126 usage() 127 { 128 (void)fprintf(stderr, "usage: fold [-bs] [-w width] [file ...]\n"); 129 exit(1); 130 } 131 132 /* 133 * Fold the contents of standard input to fit within WIDTH columns (or bytes) 134 * and write to standard output. 135 * 136 * If sflag is set, split the line at the last space character on the line. 137 * This flag necessitates storing the line in a buffer until the current 138 * column > width, or a newline or EOF is read. 139 * 140 * The buffer can grow larger than WIDTH due to backspaces and carriage 141 * returns embedded in the input stream. 142 */ 143 void 144 fold(width) 145 register int width; 146 { 147 static char *buf; 148 static int buf_max; 149 int ch, col, i, indx, space; 150 151 col = indx = 0; 152 while ((ch = getchar()) != EOF) { 153 if (ch == '\n') { 154 if (indx != 0) 155 fwrite(buf, 1, indx, stdout); 156 putchar('\n'); 157 col = indx = 0; 158 continue; 159 } 160 if ((col = newpos(col, ch)) > width) { 161 if (sflag) { 162 i = indx; 163 while (--i >= 0 && !isblank((unsigned char)buf[i])) 164 ; 165 space = i; 166 } 167 if (sflag && space != -1) { 168 space++; 169 fwrite(buf, 1, space, stdout); 170 memmove(buf, buf + space, indx - space); 171 indx -= space; 172 col = 0; 173 for (i = 0; i < indx; i++) 174 col = newpos(col, 175 (unsigned char)buf[i]); 176 } else { 177 fwrite(buf, 1, indx, stdout); 178 col = indx = 0; 179 } 180 putchar('\n'); 181 col = newpos(col, ch); 182 } 183 if (indx + 1 > buf_max) { 184 buf_max += LINE_MAX; 185 if ((buf = realloc(buf, buf_max)) == NULL) 186 err(1, "realloc()"); 187 } 188 buf[indx++] = ch; 189 } 190 191 if (indx != 0) 192 fwrite(buf, 1, indx, stdout); 193 } 194 195 /* 196 * Update the current column position for a character. 197 */ 198 static int 199 newpos(col, ch) 200 int col, ch; 201 { 202 203 if (bflag) 204 ++col; 205 else 206 switch (ch) { 207 case '\b': 208 if (col > 0) 209 --col; 210 break; 211 case '\r': 212 col = 0; 213 break; 214 case '\t': 215 col = (col + 8) & ~7; 216 break; 217 default: 218 if (isprint(ch)) 219 ++col; 220 break; 221 } 222 223 return (col); 224 } 225