1 /* 2 * SPDX-License-Identifier: BSD-3-Clause 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 #ifndef lint 33 static const char copyright[] = 34 "@(#) Copyright (c) 1987, 1990, 1993, 1994\n\ 35 The Regents of the University of California. All rights reserved.\n"; 36 #endif 37 38 #if 0 39 #ifndef lint 40 static char sccsid[] = "@(#)cmp.c 8.3 (Berkeley) 4/2/94"; 41 #endif 42 #endif 43 44 #include <sys/cdefs.h> 45 __FBSDID("$FreeBSD$"); 46 47 #include <sys/types.h> 48 #include <sys/stat.h> 49 50 #include <capsicum_helpers.h> 51 #include <err.h> 52 #include <errno.h> 53 #include <fcntl.h> 54 #include <getopt.h> 55 #include <nl_types.h> 56 #include <stdio.h> 57 #include <stdlib.h> 58 #include <string.h> 59 #include <unistd.h> 60 61 #include <libutil.h> 62 63 #include "extern.h" 64 65 bool bflag, lflag, sflag, xflag, zflag; 66 67 static const struct option long_opts[] = 68 { 69 {"print-bytes", no_argument, NULL, 'b'}, 70 {"ignore-initial", required_argument, NULL, 'i'}, 71 {"verbose", no_argument, NULL, 'l'}, 72 {"bytes", required_argument, NULL, 'n'}, 73 {"silent", no_argument, NULL, 's'}, 74 {"quiet", no_argument, NULL, 's'}, 75 {NULL, no_argument, NULL, 0} 76 }; 77 78 static void usage(void); 79 80 static bool 81 parse_iskipspec(char *spec, off_t *skip1, off_t *skip2) 82 { 83 char *colon; 84 85 colon = strchr(spec, ':'); 86 if (colon != NULL) 87 *colon++ = '\0'; 88 89 if (expand_number(spec, skip1) < 0) 90 return (false); 91 92 if (colon != NULL) 93 return (expand_number(colon, skip2) == 0); 94 95 *skip2 = *skip1; 96 return (true); 97 } 98 99 int 100 main(int argc, char *argv[]) 101 { 102 struct stat sb1, sb2; 103 off_t skip1, skip2, limit; 104 int ch, fd1, fd2, oflag; 105 bool special; 106 const char *file1, *file2; 107 108 limit = skip1 = skip2 = 0; 109 oflag = O_RDONLY; 110 while ((ch = getopt_long(argc, argv, "+bhi:ln:sxz", long_opts, NULL)) != -1) 111 switch (ch) { 112 case 'b': /* Print bytes */ 113 bflag = true; 114 break; 115 case 'h': /* Don't follow symlinks */ 116 oflag |= O_NOFOLLOW; 117 break; 118 case 'i': 119 if (!parse_iskipspec(optarg, &skip1, &skip2)) { 120 fprintf(stderr, 121 "Invalid --ignore-initial: %s\n", 122 optarg); 123 usage(); 124 } 125 break; 126 case 'l': /* print all differences */ 127 lflag = true; 128 break; 129 case 'n': /* Limit */ 130 if (expand_number(optarg, &limit) < 0 || limit < 0) { 131 fprintf(stderr, "Invalid --bytes: %s\n", 132 optarg); 133 usage(); 134 } 135 break; 136 case 's': /* silent run */ 137 sflag = true; 138 break; 139 case 'x': /* hex output */ 140 lflag = true; 141 xflag = true; 142 break; 143 case 'z': /* compare size first */ 144 zflag = true; 145 break; 146 case '?': 147 default: 148 usage(); 149 } 150 argv += optind; 151 argc -= optind; 152 153 if (lflag && sflag) 154 errx(ERR_EXIT, "specifying -s with -l or -x is not permitted"); 155 156 if (argc < 2 || argc > 4) 157 usage(); 158 159 /* Don't limit rights on stdin since it may be one of the inputs. */ 160 if (caph_limit_stream(STDOUT_FILENO, CAPH_WRITE | CAPH_IGNORE_EBADF)) 161 err(ERR_EXIT, "unable to limit rights on stdout"); 162 if (caph_limit_stream(STDERR_FILENO, CAPH_WRITE | CAPH_IGNORE_EBADF)) 163 err(ERR_EXIT, "unable to limit rights on stderr"); 164 165 /* Backward compatibility -- handle "-" meaning stdin. */ 166 special = false; 167 if (strcmp(file1 = argv[0], "-") == 0) { 168 special = true; 169 fd1 = STDIN_FILENO; 170 file1 = "stdin"; 171 } else if ((fd1 = open(file1, oflag, 0)) < 0 && errno != EMLINK) { 172 if (!sflag) 173 err(ERR_EXIT, "%s", file1); 174 else 175 exit(ERR_EXIT); 176 } 177 if (strcmp(file2 = argv[1], "-") == 0) { 178 if (special) 179 errx(ERR_EXIT, 180 "standard input may only be specified once"); 181 special = true; 182 fd2 = STDIN_FILENO; 183 file2 = "stdin"; 184 } else if ((fd2 = open(file2, oflag, 0)) < 0 && errno != EMLINK) { 185 if (!sflag) 186 err(ERR_EXIT, "%s", file2); 187 else 188 exit(ERR_EXIT); 189 } 190 191 if (argc > 2 && expand_number(argv[2], &skip1) < 0) { 192 fprintf(stderr, "Invalid skip1: %s\n", argv[2]); 193 usage(); 194 } 195 196 if (argc == 4 && expand_number(argv[3], &skip2) < 0) { 197 fprintf(stderr, "Invalid skip2: %s\n", argv[3]); 198 usage(); 199 } 200 201 if (sflag && skip1 == 0 && skip2 == 0) 202 zflag = true; 203 204 if (fd1 == -1) { 205 if (fd2 == -1) { 206 c_link(file1, skip1, file2, skip2, limit); 207 exit(0); 208 } else if (!sflag) 209 errx(ERR_EXIT, "%s: Not a symbolic link", file2); 210 else 211 exit(ERR_EXIT); 212 } else if (fd2 == -1) { 213 if (!sflag) 214 errx(ERR_EXIT, "%s: Not a symbolic link", file1); 215 else 216 exit(ERR_EXIT); 217 } 218 219 /* FD rights are limited in c_special() and c_regular(). */ 220 caph_cache_catpages(); 221 222 if (!special) { 223 if (fstat(fd1, &sb1)) { 224 if (!sflag) 225 err(ERR_EXIT, "%s", file1); 226 else 227 exit(ERR_EXIT); 228 } 229 if (!S_ISREG(sb1.st_mode)) 230 special = true; 231 else { 232 if (fstat(fd2, &sb2)) { 233 if (!sflag) 234 err(ERR_EXIT, "%s", file2); 235 else 236 exit(ERR_EXIT); 237 } 238 if (!S_ISREG(sb2.st_mode)) 239 special = true; 240 } 241 } 242 243 if (special) 244 c_special(fd1, file1, skip1, fd2, file2, skip2, limit); 245 else { 246 if (zflag && sb1.st_size != sb2.st_size) { 247 if (!sflag) 248 (void) printf("%s %s differ: size\n", 249 file1, file2); 250 exit(DIFF_EXIT); 251 } 252 c_regular(fd1, file1, skip1, sb1.st_size, 253 fd2, file2, skip2, sb2.st_size, limit); 254 } 255 exit(0); 256 } 257 258 static void 259 usage(void) 260 { 261 262 (void)fprintf(stderr, 263 "usage: cmp [-l | -s | -x] [-hz] file1 file2 [skip1 [skip2]]\n"); 264 exit(ERR_EXIT); 265 } 266