cmp.c revision 1.13
1/* $NetBSD: cmp.c,v 1.13 2003/08/07 11:13:22 agc 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 40static char sccsid[] = "@(#)cmp.c 8.3 (Berkeley) 4/2/94"; 41#else 42__RCSID("$NetBSD: cmp.c,v 1.13 2003/08/07 11:13:22 agc 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 59int lflag, sflag; 60 61int main __P((int, char **)); 62static void usage __P((void)); 63 64int 65main(argc, argv) 66 int argc; 67 char *argv[]; 68{ 69 struct stat sb1, sb2; 70 off_t skip1, skip2; 71 int ch, fd1, fd2, special; 72 char *file1, *file2; 73 74 setlocale(LC_ALL, ""); 75 76 while ((ch = getopt(argc, argv, "ls")) != -1) 77 switch (ch) { 78 case 'l': /* print all differences */ 79 lflag = 1; 80 break; 81 case 's': /* silent run */ 82 sflag = 1; 83 break; 84 case '?': 85 default: 86 usage(); 87 } 88 argv += optind; 89 argc -= optind; 90 91 if (lflag && sflag) 92 errx(ERR_EXIT, "only one of -l and -s may be specified"); 93 94 if (argc < 2 || argc > 4) 95 usage(); 96 97 /* Backward compatibility -- handle "-" meaning stdin. */ 98 special = 0; 99 if (strcmp(file1 = argv[0], "-") == 0) { 100 special = 1; 101 fd1 = 0; 102 file1 = "stdin"; 103 } 104 else if ((fd1 = open(file1, O_RDONLY, 0)) < 0) { 105 if (!sflag) 106 warn("%s", file1); 107 exit(ERR_EXIT); 108 } 109 if (strcmp(file2 = argv[1], "-") == 0) { 110 if (special) 111 errx(ERR_EXIT, 112 "standard input may only be specified once"); 113 special = 1; 114 fd2 = 0; 115 file2 = "stdin"; 116 } 117 else if ((fd2 = open(file2, O_RDONLY, 0)) < 0) { 118 if (!sflag) 119 warn("%s", file2); 120 exit(ERR_EXIT); 121 } 122 123 skip1 = argc > 2 ? strtoq(argv[2], NULL, 10) : 0; 124 skip2 = argc == 4 ? strtoq(argv[3], NULL, 10) : 0; 125 126 if (!special) { 127 if (fstat(fd1, &sb1)) 128 err(ERR_EXIT, "%s", file1); 129 if (!S_ISREG(sb1.st_mode)) 130 special = 1; 131 else { 132 if (fstat(fd2, &sb2)) 133 err(ERR_EXIT, "%s", file2); 134 if (!S_ISREG(sb2.st_mode)) 135 special = 1; 136 } 137 } 138 139 if (special) 140 c_special(fd1, file1, skip1, fd2, file2, skip2); 141 else 142 c_regular(fd1, file1, skip1, sb1.st_size, 143 fd2, file2, skip2, sb2.st_size); 144 exit(0); 145} 146 147static void 148usage() 149{ 150 151 (void)fprintf(stderr, 152 "usage: cmp [-l | -s] file1 file2 [skip1 [skip2]]\n"); 153 exit(ERR_EXIT); 154} 155