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. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#) Copyright (c) 1987, 1992, 1993 The Regents of the University of California. All rights reserved. 30 * @(#)rev.c 8.3 (Berkeley) 5/4/95 31 * $DragonFly: src/usr.bin/rev/rev.c,v 1.8 2008/10/16 01:52:33 swildner Exp $ 32 */ 33 34 #include <sys/types.h> 35 36 #include <err.h> 37 #include <stdio.h> 38 #include <stdlib.h> 39 #include <unistd.h> 40 41 static void usage(void); 42 static int dorev(FILE *, const char *); 43 44 int 45 main(int argc, char **argv) 46 { 47 FILE *fp; 48 int ch, i, rval; 49 50 rval = 0; 51 52 while ((ch = getopt(argc, argv, "")) != -1) 53 switch(ch) { 54 case '?': 55 default: 56 usage(); 57 } 58 59 argc -= optind; 60 argv += optind; 61 62 if (argc == 0) 63 rval += dorev(stdin, "stdin"); 64 65 for (i = 0; i < argc; ++i) { 66 if ((fp = fopen(argv[i], "r")) != NULL) { 67 rval += dorev(fp, argv[i]); 68 fclose(fp); 69 } else { 70 warn("failed to open %s", argv[i]); 71 rval++ ; 72 } 73 } 74 75 exit(rval != 0 ? 1 : 0); 76 } 77 78 static void 79 usage(void) 80 { 81 fprintf(stderr, "usage: rev [file ...]\n"); 82 exit(1); 83 } 84 85 static int 86 dorev(FILE *fp, const char *filepath) 87 { 88 const char *p, *t; 89 size_t len; 90 91 while ((p = fgetln(fp, &len)) != NULL) { 92 if (p[len - 1] == '\n') 93 --len; 94 for (t = p + len - 1; t >= p; --t) 95 putchar(*t); 96 putchar('\n'); 97 } 98 99 if (ferror(fp)) { 100 warn("%s", filepath); 101 /* Reset error indicator */ 102 clearerr(fp); 103 return(1); 104 } 105 106 return(0); 107 } 108