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 #include <sys/types.h> 46 #include <sys/stat.h> 47 48 #include <capsicum_helpers.h> 49 #include <err.h> 50 #include <errno.h> 51 #include <fcntl.h> 52 #include <getopt.h> 53 #include <nl_types.h> 54 #include <stdio.h> 55 #include <stdlib.h> 56 #include <string.h> 57 #include <unistd.h> 58 59 #include <libutil.h> 60 61 #include "extern.h" 62 63 bool bflag, lflag, sflag, xflag, zflag; 64 65 static const struct option long_opts[] = 66 { 67 {"print-bytes", no_argument, NULL, 'b'}, 68 {"ignore-initial", required_argument, NULL, 'i'}, 69 {"verbose", no_argument, NULL, 'l'}, 70 {"bytes", required_argument, NULL, 'n'}, 71 {"silent", no_argument, NULL, 's'}, 72 {"quiet", no_argument, NULL, 's'}, 73 {NULL, no_argument, NULL, 0} 74 }; 75 76 #ifdef SIGINFO 77 volatile sig_atomic_t info; 78 79 static void 80 siginfo(int signo) 81 { 82 83 info = signo; 84 } 85 #endif 86 87 static void usage(void) __dead2; 88 89 static bool 90 parse_iskipspec(char *spec, off_t *skip1, off_t *skip2) 91 { 92 char *colon; 93 94 colon = strchr(spec, ':'); 95 if (colon != NULL) 96 *colon++ = '\0'; 97 98 if (expand_number(spec, skip1) < 0) 99 return (false); 100 101 if (colon != NULL) 102 return (expand_number(colon, skip2) == 0); 103 104 *skip2 = *skip1; 105 return (true); 106 } 107 108 int 109 main(int argc, char *argv[]) 110 { 111 struct stat sb1, sb2; 112 off_t skip1, skip2, limit; 113 int ch, fd1, fd2, oflag; 114 bool special; 115 const char *file1, *file2; 116 117 limit = skip1 = skip2 = 0; 118 oflag = O_RDONLY; 119 while ((ch = getopt_long(argc, argv, "+bhi:ln:sxz", long_opts, NULL)) != -1) 120 switch (ch) { 121 case 'b': /* Print bytes */ 122 bflag = true; 123 break; 124 case 'h': /* Don't follow symlinks */ 125 oflag |= O_NOFOLLOW; 126 break; 127 case 'i': 128 if (!parse_iskipspec(optarg, &skip1, &skip2)) { 129 fprintf(stderr, 130 "Invalid --ignore-initial: %s\n", 131 optarg); 132 usage(); 133 } 134 break; 135 case 'l': /* print all differences */ 136 lflag = true; 137 break; 138 case 'n': /* Limit */ 139 if (expand_number(optarg, &limit) < 0 || limit < 0) { 140 fprintf(stderr, "Invalid --bytes: %s\n", 141 optarg); 142 usage(); 143 } 144 break; 145 case 's': /* silent run */ 146 sflag = true; 147 break; 148 case 'x': /* hex output */ 149 lflag = true; 150 xflag = true; 151 break; 152 case 'z': /* compare size first */ 153 zflag = true; 154 break; 155 case '?': 156 default: 157 usage(); 158 } 159 argv += optind; 160 argc -= optind; 161 162 if (lflag && sflag) 163 errx(ERR_EXIT, "specifying -s with -l or -x is not permitted"); 164 165 if (argc < 2 || argc > 4) 166 usage(); 167 168 /* Don't limit rights on stdin since it may be one of the inputs. */ 169 if (caph_limit_stream(STDOUT_FILENO, CAPH_WRITE | CAPH_IGNORE_EBADF)) 170 err(ERR_EXIT, "unable to limit rights on stdout"); 171 if (caph_limit_stream(STDERR_FILENO, CAPH_WRITE | CAPH_IGNORE_EBADF)) 172 err(ERR_EXIT, "unable to limit rights on stderr"); 173 174 /* Backward compatibility -- handle "-" meaning stdin. */ 175 special = false; 176 if (strcmp(file1 = argv[0], "-") == 0) { 177 special = true; 178 fd1 = STDIN_FILENO; 179 file1 = "stdin"; 180 } else if ((fd1 = open(file1, oflag, 0)) < 0 && errno != EMLINK) { 181 if (!sflag) 182 err(ERR_EXIT, "%s", file1); 183 else 184 exit(ERR_EXIT); 185 } 186 if (strcmp(file2 = argv[1], "-") == 0) { 187 if (special) 188 errx(ERR_EXIT, 189 "standard input may only be specified once"); 190 special = true; 191 fd2 = STDIN_FILENO; 192 file2 = "stdin"; 193 } else if ((fd2 = open(file2, oflag, 0)) < 0 && errno != EMLINK) { 194 if (!sflag) 195 err(ERR_EXIT, "%s", file2); 196 else 197 exit(ERR_EXIT); 198 } 199 200 if (argc > 2 && expand_number(argv[2], &skip1) < 0) { 201 fprintf(stderr, "Invalid skip1: %s\n", argv[2]); 202 usage(); 203 } 204 205 if (argc == 4 && expand_number(argv[3], &skip2) < 0) { 206 fprintf(stderr, "Invalid skip2: %s\n", argv[3]); 207 usage(); 208 } 209 210 if (sflag && skip1 == 0 && skip2 == 0) 211 zflag = true; 212 213 if (fd1 == -1) { 214 if (fd2 == -1) { 215 c_link(file1, skip1, file2, skip2, limit); 216 exit(0); 217 } else if (!sflag) 218 errx(ERR_EXIT, "%s: Not a symbolic link", file2); 219 else 220 exit(ERR_EXIT); 221 } else if (fd2 == -1) { 222 if (!sflag) 223 errx(ERR_EXIT, "%s: Not a symbolic link", file1); 224 else 225 exit(ERR_EXIT); 226 } 227 228 /* FD rights are limited in c_special() and c_regular(). */ 229 caph_cache_catpages(); 230 231 if (!special) { 232 if (fstat(fd1, &sb1)) { 233 if (!sflag) 234 err(ERR_EXIT, "%s", file1); 235 else 236 exit(ERR_EXIT); 237 } 238 if (!S_ISREG(sb1.st_mode)) 239 special = true; 240 else { 241 if (fstat(fd2, &sb2)) { 242 if (!sflag) 243 err(ERR_EXIT, "%s", file2); 244 else 245 exit(ERR_EXIT); 246 } 247 if (!S_ISREG(sb2.st_mode)) 248 special = true; 249 } 250 } 251 252 #ifdef SIGINFO 253 (void)signal(SIGINFO, siginfo); 254 #endif 255 if (special) 256 c_special(fd1, file1, skip1, fd2, file2, skip2, limit); 257 else { 258 if (zflag && sb1.st_size != sb2.st_size) { 259 if (!sflag) 260 (void) printf("%s %s differ: size\n", 261 file1, file2); 262 exit(DIFF_EXIT); 263 } 264 c_regular(fd1, file1, skip1, sb1.st_size, 265 fd2, file2, skip2, sb2.st_size, limit); 266 } 267 exit(0); 268 } 269 270 static void 271 usage(void) 272 { 273 274 (void)fprintf(stderr, 275 "usage: cmp [-l | -s | -x] [-hz] file1 file2 [skip1 [skip2]]\n"); 276 exit(ERR_EXIT); 277 } 278