1 /*- 2 * Copyright (c) 1987, 1992, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#) Copyright (c) 1987, 1992, 1993 The Regents of the University of California. All rights reserved. 34 * @(#)rev.c 8.3 (Berkeley) 5/4/95 35 * $DragonFly: src/usr.bin/rev/rev.c,v 1.7 2006/07/30 06:49:39 dillon Exp $ 36 */ 37 38 #include <sys/types.h> 39 40 #include <err.h> 41 #include <stdio.h> 42 #include <stdlib.h> 43 #include <unistd.h> 44 45 static void usage(void); 46 static int dorev(FILE *, const char *); 47 48 int 49 main(int argc, char **argv) 50 { 51 FILE *fp; 52 int ch, i, rval; 53 54 rval = 0; 55 56 while ((ch = getopt(argc, argv, "")) != -1) 57 switch(ch) { 58 case '?': 59 default: 60 usage(); 61 } 62 63 argc -= optind; 64 argv += optind; 65 66 if (argc == 0) 67 rval += dorev(stdin, "stdin"); 68 69 for (i = 0; i < argc; ++i) { 70 if ((fp = fopen(argv[i], "r")) != NULL) { 71 rval += dorev(fp, argv[i]); 72 fclose(fp); 73 } else { 74 warn("failed to open %s", argv[i]); 75 rval++ ; 76 } 77 } 78 79 exit(rval != 0 ? 1 : 0); 80 } 81 82 static void 83 usage() 84 { 85 fprintf(stderr, "usage: rev [file ...]\n"); 86 exit(1); 87 } 88 89 static int 90 dorev(FILE *fp, const char *filepath) 91 { 92 const char *p, *t; 93 size_t len; 94 95 while ((p = fgetln(fp, &len)) != NULL) { 96 if (p[len - 1] == '\n') 97 --len; 98 for (t = p + len - 1; t >= p; --t) 99 putchar(*t); 100 putchar('\n'); 101 } 102 103 if (ferror(fp)) { 104 warn("%s", filepath); 105 /* Reset error indicator */ 106 clearerr(fp); 107 return(1); 108 } 109 110 return(0); 111 } 112