1 /* $OpenBSD: colrm.c,v 1.9 2009/10/27 23:59:36 deraadt Exp $ */ 2 /* $NetBSD: colrm.c,v 1.4 1995/09/02 05:51:37 jtc Exp $ */ 3 4 /*- 5 * Copyright (c) 1991, 1993 6 * The Regents of the University of California. All rights reserved. 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. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 #include <sys/types.h> 34 35 #include <err.h> 36 #include <errno.h> 37 #include <limits.h> 38 #include <stdio.h> 39 #include <stdlib.h> 40 #include <string.h> 41 #include <unistd.h> 42 43 #define TAB 8 44 45 void check(FILE *); 46 void usage(void); 47 48 int 49 main(int argc, char *argv[]) 50 { 51 u_long column, start, stop; 52 int ch; 53 char *p; 54 55 while ((ch = getopt(argc, argv, "")) != -1) 56 switch(ch) { 57 case '?': 58 default: 59 usage(); 60 } 61 argc -= optind; 62 argv += optind; 63 64 start = stop = 0; 65 switch(argc) { 66 case 2: 67 stop = strtol(argv[1], &p, 10); 68 if (stop <= 0 || *p) 69 errx(1, "illegal column -- %s", argv[1]); 70 /* FALLTHROUGH */ 71 case 1: 72 start = strtol(argv[0], &p, 10); 73 if (start <= 0 || *p) 74 errx(1, "illegal column -- %s", argv[0]); 75 break; 76 case 0: 77 break; 78 default: 79 usage(); 80 } 81 82 if (stop && start > stop) 83 err(1, "illegal start and stop columns"); 84 85 for (column = 0;;) { 86 switch (ch = getchar()) { 87 case EOF: 88 check(stdin); 89 break; 90 case '\b': 91 if (column) 92 --column; 93 break; 94 case '\n': 95 column = 0; 96 break; 97 case '\t': 98 column = (column + TAB) & ~(TAB - 1); 99 break; 100 default: 101 ++column; 102 break; 103 } 104 105 if ((!start || column < start || (stop && column > stop)) && 106 putchar(ch) == EOF) 107 check(stdout); 108 } 109 } 110 111 void 112 check(FILE *stream) 113 { 114 if (feof(stream)) 115 exit(0); 116 if (ferror(stream)) 117 err(1, "%s", stream == stdin ? "stdin" : "stdout"); 118 } 119 120 void 121 usage(void) 122 { 123 (void)fprintf(stderr, "usage: colrm [start [stop]]\n"); 124 exit(1); 125 } 126