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 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 static char sccsid[] = "@(#)fold.c 8.1 (Berkeley) 6/6/93"; 45 #endif /* not lint */ 46 47 #include <stdio.h> 48 #include <string.h> 49 50 #define DEFLINEWIDTH 80 51 52 main(argc, argv) 53 int argc; 54 char **argv; 55 { 56 extern int errno, optind; 57 extern char *optarg; 58 register int ch; 59 int width; 60 char *p; 61 62 width = -1; 63 while ((ch = getopt(argc, argv, "0123456789w:")) != -1) 64 switch (ch) { 65 case 'w': 66 if ((width = atoi(optarg)) <= 0) { 67 (void)fprintf(stderr, 68 "fold: illegal width value.\n"); 69 exit(1); 70 } 71 break; 72 case '0': case '1': case '2': case '3': case '4': 73 case '5': case '6': case '7': case '8': case '9': 74 if (width == -1) { 75 p = argv[optind - 1]; 76 if (p[0] == '-' && p[1] == ch && !p[2]) 77 width = atoi(++p); 78 else 79 width = atoi(argv[optind] + 1); 80 } 81 break; 82 default: 83 (void)fprintf(stderr, 84 "usage: fold [-w width] [file ...]\n"); 85 exit(1); 86 } 87 argv += optind; 88 argc -= optind; 89 90 if (width == -1) 91 width = DEFLINEWIDTH; 92 if (!*argv) 93 fold(width); 94 else for (; *argv; ++argv) 95 if (!freopen(*argv, "r", stdin)) { 96 (void)fprintf(stderr, 97 "fold: %s: %s\n", *argv, strerror(errno)); 98 exit(1); 99 } else 100 fold(width); 101 exit(0); 102 } 103 104 fold(width) 105 register int width; 106 { 107 register int ch, col, new; 108 109 for (col = 0;;) { 110 switch (ch = getchar()) { 111 case EOF: 112 return; 113 case '\b': 114 new = col ? col - 1 : 0; 115 break; 116 case '\n': 117 case '\r': 118 new = 0; 119 break; 120 case '\t': 121 new = (col + 8) & ~7; 122 break; 123 default: 124 new = col + 1; 125 break; 126 } 127 128 if (new > width) { 129 putchar('\n'); 130 col = 0; 131 } 132 putchar(ch); 133 134 switch (ch) { 135 case '\b': 136 if (col > 0) 137 --col; 138 break; 139 case '\n': 140 case '\r': 141 col = 0; 142 break; 143 case '\t': 144 col += 8; 145 col &= ~7; 146 break; 147 default: 148 ++col; 149 break; 150 } 151 } 152 } 153