1 /* $NetBSD: cmp.c,v 1.14 2005/02/06 20:50:34 dsl Exp $ */ 2 3 /* 4 * Copyright (c) 1987, 1990, 1993, 1994 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 #ifndef lint 34 __COPYRIGHT("@(#) Copyright (c) 1987, 1990, 1993, 1994\n\ 35 The Regents of the University of California. All rights reserved.\n"); 36 #endif /* not lint */ 37 38 #ifndef lint 39 #if 0 40 static char sccsid[] = "@(#)cmp.c 8.3 (Berkeley) 4/2/94"; 41 #else 42 __RCSID("$NetBSD: cmp.c,v 1.14 2005/02/06 20:50:34 dsl Exp $"); 43 #endif 44 #endif /* not lint */ 45 46 #include <sys/types.h> 47 #include <sys/stat.h> 48 49 #include <err.h> 50 #include <fcntl.h> 51 #include <stdio.h> 52 #include <stdlib.h> 53 #include <string.h> 54 #include <unistd.h> 55 #include <locale.h> 56 57 #include "extern.h" 58 59 int lflag, sflag; 60 61 static void usage(void); 62 63 int 64 main(int argc, char *argv[]) 65 { 66 struct stat sb1, sb2; 67 off_t skip1, skip2; 68 int ch, fd1, fd2, special; 69 char *file1, *file2; 70 71 setlocale(LC_ALL, ""); 72 73 while ((ch = getopt(argc, argv, "ls")) != -1) 74 switch (ch) { 75 case 'l': /* print all differences */ 76 lflag = 1; 77 break; 78 case 's': /* silent run */ 79 sflag = 1; 80 break; 81 case '?': 82 default: 83 usage(); 84 } 85 argv += optind; 86 argc -= optind; 87 88 if (lflag && sflag) 89 errx(ERR_EXIT, "only one of -l and -s may be specified"); 90 91 if (argc < 2 || argc > 4) 92 usage(); 93 94 /* Backward compatibility -- handle "-" meaning stdin. */ 95 special = 0; 96 if (strcmp(file1 = argv[0], "-") == 0) { 97 special = 1; 98 fd1 = 0; 99 file1 = "stdin"; 100 } 101 else if ((fd1 = open(file1, O_RDONLY, 0)) < 0) { 102 if (!sflag) 103 warn("%s", file1); 104 exit(ERR_EXIT); 105 } 106 if (strcmp(file2 = argv[1], "-") == 0) { 107 if (special) 108 errx(ERR_EXIT, 109 "standard input may only be specified once"); 110 special = 1; 111 fd2 = 0; 112 file2 = "stdin"; 113 } 114 else if ((fd2 = open(file2, O_RDONLY, 0)) < 0) { 115 if (!sflag) 116 warn("%s", file2); 117 exit(ERR_EXIT); 118 } 119 120 skip1 = argc > 2 ? strtoq(argv[2], NULL, 10) : 0; 121 skip2 = argc == 4 ? strtoq(argv[3], NULL, 10) : 0; 122 123 if (!special) { 124 if (fstat(fd1, &sb1)) 125 err(ERR_EXIT, "%s", file1); 126 if (!S_ISREG(sb1.st_mode)) 127 special = 1; 128 else { 129 if (fstat(fd2, &sb2)) 130 err(ERR_EXIT, "%s", file2); 131 if (!S_ISREG(sb2.st_mode)) 132 special = 1; 133 } 134 } 135 136 if (special) 137 c_special(fd1, file1, skip1, fd2, file2, skip2); 138 else 139 c_regular(fd1, file1, skip1, sb1.st_size, 140 fd2, file2, skip2, sb2.st_size); 141 exit(0); 142 } 143 144 static void 145 usage(void) 146 { 147 148 (void)fprintf(stderr, 149 "usage: cmp [-l | -s] file1 file2 [skip1 [skip2]]\n"); 150 exit(ERR_EXIT); 151 } 152