1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1992, 1993 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) 1992, 1993\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[] = "@(#)compress.c 8.2 (Berkeley) 1/7/94"; 41 #endif 42 #endif 43 44 #include <sys/cdefs.h> 45 __FBSDID("$FreeBSD$"); 46 47 #include <sys/param.h> 48 #include <sys/stat.h> 49 #include <sys/time.h> 50 51 #include <err.h> 52 #include <errno.h> 53 #include <fcntl.h> 54 #include <stdarg.h> 55 #include <stdio.h> 56 #include <stdlib.h> 57 #include <string.h> 58 #include <unistd.h> 59 60 #include "zopen.h" 61 62 static void compress(const char *, const char *, int); 63 static void cwarn(const char *, ...) __printflike(1, 2); 64 static void cwarnx(const char *, ...) __printflike(1, 2); 65 static void decompress(const char *, const char *, int); 66 static int permission(const char *); 67 static void setfile(const char *, struct stat *); 68 static void usage(int); 69 70 static int eval, force, verbose; 71 72 int 73 main(int argc, char *argv[]) 74 { 75 enum {COMPRESS, DECOMPRESS} style; 76 size_t len; 77 int bits, cat, ch; 78 char *p, newname[MAXPATHLEN]; 79 80 cat = 0; 81 if ((p = strrchr(argv[0], '/')) == NULL) 82 p = argv[0]; 83 else 84 ++p; 85 if (!strcmp(p, "uncompress")) 86 style = DECOMPRESS; 87 else if (!strcmp(p, "compress")) 88 style = COMPRESS; 89 else if (!strcmp(p, "zcat")) { 90 cat = 1; 91 style = DECOMPRESS; 92 } else 93 errx(1, "unknown program name"); 94 95 bits = 0; 96 while ((ch = getopt(argc, argv, "b:cdfv")) != -1) 97 switch(ch) { 98 case 'b': 99 bits = strtol(optarg, &p, 10); 100 if (*p) 101 errx(1, "illegal bit count -- %s", optarg); 102 break; 103 case 'c': 104 cat = 1; 105 break; 106 case 'd': /* Backward compatible. */ 107 style = DECOMPRESS; 108 break; 109 case 'f': 110 force = 1; 111 break; 112 case 'v': 113 verbose = 1; 114 break; 115 case '?': 116 default: 117 usage(style == COMPRESS); 118 } 119 argc -= optind; 120 argv += optind; 121 122 if (argc == 0) { 123 switch(style) { 124 case COMPRESS: 125 (void)compress("/dev/stdin", "/dev/stdout", bits); 126 break; 127 case DECOMPRESS: 128 (void)decompress("/dev/stdin", "/dev/stdout", bits); 129 break; 130 } 131 exit (eval); 132 } 133 134 if (cat == 1 && style == COMPRESS && argc > 1) 135 errx(1, "the -c option permits only a single file argument"); 136 137 for (; *argv; ++argv) 138 switch(style) { 139 case COMPRESS: 140 if (strcmp(*argv, "-") == 0) { 141 compress("/dev/stdin", "/dev/stdout", bits); 142 break; 143 } else if (cat) { 144 compress(*argv, "/dev/stdout", bits); 145 break; 146 } 147 if ((p = strrchr(*argv, '.')) != NULL && 148 !strcmp(p, ".Z")) { 149 cwarnx("%s: name already has trailing .Z", 150 *argv); 151 break; 152 } 153 len = strlen(*argv); 154 if (len > sizeof(newname) - 3) { 155 cwarnx("%s: name too long", *argv); 156 break; 157 } 158 memmove(newname, *argv, len); 159 newname[len] = '.'; 160 newname[len + 1] = 'Z'; 161 newname[len + 2] = '\0'; 162 compress(*argv, newname, bits); 163 break; 164 case DECOMPRESS: 165 if (strcmp(*argv, "-") == 0) { 166 decompress("/dev/stdin", "/dev/stdout", bits); 167 break; 168 } 169 len = strlen(*argv); 170 if ((p = strrchr(*argv, '.')) == NULL || 171 strcmp(p, ".Z")) { 172 if (len > sizeof(newname) - 3) { 173 cwarnx("%s: name too long", *argv); 174 break; 175 } 176 memmove(newname, *argv, len); 177 newname[len] = '.'; 178 newname[len + 1] = 'Z'; 179 newname[len + 2] = '\0'; 180 decompress(newname, 181 cat ? "/dev/stdout" : *argv, bits); 182 } else { 183 if (len - 2 > sizeof(newname) - 1) { 184 cwarnx("%s: name too long", *argv); 185 break; 186 } 187 memmove(newname, *argv, len - 2); 188 newname[len - 2] = '\0'; 189 decompress(*argv, 190 cat ? "/dev/stdout" : newname, bits); 191 } 192 break; 193 } 194 exit (eval); 195 } 196 197 static void 198 compress(const char *in, const char *out, int bits) 199 { 200 size_t nr; 201 struct stat isb, sb; 202 FILE *ifp, *ofp; 203 int exists, isreg, oreg; 204 u_char buf[1024]; 205 206 exists = !stat(out, &sb); 207 if (!force && exists && S_ISREG(sb.st_mode) && !permission(out)) 208 return; 209 isreg = oreg = !exists || S_ISREG(sb.st_mode); 210 211 ifp = ofp = NULL; 212 if ((ifp = fopen(in, "r")) == NULL) { 213 cwarn("%s", in); 214 return; 215 } 216 if (stat(in, &isb)) { /* DON'T FSTAT! */ 217 cwarn("%s", in); 218 goto err; 219 } 220 if (!S_ISREG(isb.st_mode)) 221 isreg = 0; 222 223 if ((ofp = zopen(out, "w", bits)) == NULL) { 224 cwarn("%s", out); 225 goto err; 226 } 227 while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0) 228 if (fwrite(buf, 1, nr, ofp) != nr) { 229 cwarn("%s", out); 230 goto err; 231 } 232 233 if (ferror(ifp) || fclose(ifp)) { 234 cwarn("%s", in); 235 goto err; 236 } 237 ifp = NULL; 238 239 if (fclose(ofp)) { 240 cwarn("%s", out); 241 goto err; 242 } 243 ofp = NULL; 244 245 if (isreg) { 246 if (stat(out, &sb)) { 247 cwarn("%s", out); 248 goto err; 249 } 250 251 if (!force && sb.st_size >= isb.st_size) { 252 if (verbose) 253 (void)fprintf(stderr, "%s: file would grow; left unmodified\n", 254 in); 255 eval = 2; 256 if (unlink(out)) 257 cwarn("%s", out); 258 goto err; 259 } 260 261 setfile(out, &isb); 262 263 if (unlink(in)) 264 cwarn("%s", in); 265 266 if (verbose) { 267 (void)fprintf(stderr, "%s: ", out); 268 if (isb.st_size > sb.st_size) 269 (void)fprintf(stderr, "%.0f%% compression\n", 270 ((float)sb.st_size / isb.st_size) * 100.0); 271 else 272 (void)fprintf(stderr, "%.0f%% expansion\n", 273 ((float)isb.st_size / sb.st_size) * 100.0); 274 } 275 } 276 return; 277 278 err: if (ofp) { 279 if (oreg) 280 (void)unlink(out); 281 (void)fclose(ofp); 282 } 283 if (ifp) 284 (void)fclose(ifp); 285 } 286 287 static void 288 decompress(const char *in, const char *out, int bits) 289 { 290 size_t nr; 291 struct stat sb; 292 FILE *ifp, *ofp; 293 int exists, isreg, oreg; 294 u_char buf[1024]; 295 296 exists = !stat(out, &sb); 297 if (!force && exists && S_ISREG(sb.st_mode) && !permission(out)) 298 return; 299 isreg = oreg = !exists || S_ISREG(sb.st_mode); 300 301 ifp = ofp = NULL; 302 if ((ifp = zopen(in, "r", bits)) == NULL) { 303 cwarn("%s", in); 304 return; 305 } 306 if (stat(in, &sb)) { 307 cwarn("%s", in); 308 goto err; 309 } 310 if (!S_ISREG(sb.st_mode)) 311 isreg = 0; 312 313 /* 314 * Try to read the first few uncompressed bytes from the input file 315 * before blindly truncating the output file. 316 */ 317 if ((nr = fread(buf, 1, sizeof(buf), ifp)) == 0) { 318 cwarn("%s", in); 319 (void)fclose(ifp); 320 return; 321 } 322 if ((ofp = fopen(out, "w")) == NULL || 323 (nr != 0 && fwrite(buf, 1, nr, ofp) != nr)) { 324 cwarn("%s", out); 325 if (ofp) 326 (void)fclose(ofp); 327 (void)fclose(ifp); 328 return; 329 } 330 331 while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0) 332 if (fwrite(buf, 1, nr, ofp) != nr) { 333 cwarn("%s", out); 334 goto err; 335 } 336 337 if (ferror(ifp) || fclose(ifp)) { 338 cwarn("%s", in); 339 goto err; 340 } 341 ifp = NULL; 342 343 if (fclose(ofp)) { 344 cwarn("%s", out); 345 goto err; 346 } 347 348 if (isreg) { 349 setfile(out, &sb); 350 351 if (unlink(in)) 352 cwarn("%s", in); 353 } 354 return; 355 356 err: if (ofp) { 357 if (oreg) 358 (void)unlink(out); 359 (void)fclose(ofp); 360 } 361 if (ifp) 362 (void)fclose(ifp); 363 } 364 365 static void 366 setfile(const char *name, struct stat *fs) 367 { 368 static struct timespec tspec[2]; 369 370 fs->st_mode &= S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO; 371 372 tspec[0] = fs->st_atim; 373 tspec[1] = fs->st_mtim; 374 if (utimensat(AT_FDCWD, name, tspec, 0)) 375 cwarn("utimensat: %s", name); 376 377 /* 378 * Changing the ownership probably won't succeed, unless we're root 379 * or POSIX_CHOWN_RESTRICTED is not set. Set uid/gid before setting 380 * the mode; current BSD behavior is to remove all setuid bits on 381 * chown. If chown fails, lose setuid/setgid bits. 382 */ 383 if (chown(name, fs->st_uid, fs->st_gid)) { 384 if (errno != EPERM) 385 cwarn("chown: %s", name); 386 fs->st_mode &= ~(S_ISUID|S_ISGID); 387 } 388 if (chmod(name, fs->st_mode) && errno != EOPNOTSUPP) 389 cwarn("chmod: %s", name); 390 391 if (chflags(name, fs->st_flags) && errno != EOPNOTSUPP) 392 cwarn("chflags: %s", name); 393 } 394 395 static int 396 permission(const char *fname) 397 { 398 int ch, first; 399 400 if (!isatty(fileno(stderr))) 401 return (0); 402 (void)fprintf(stderr, "overwrite %s? ", fname); 403 first = ch = getchar(); 404 while (ch != '\n' && ch != EOF) 405 ch = getchar(); 406 return (first == 'y'); 407 } 408 409 static void 410 usage(int iscompress) 411 { 412 if (iscompress) 413 (void)fprintf(stderr, 414 "usage: compress [-cfv] [-b bits] [file ...]\n"); 415 else 416 (void)fprintf(stderr, 417 "usage: uncompress [-c] [-b bits] [file ...]\n"); 418 exit(1); 419 } 420 421 static void 422 cwarnx(const char *fmt, ...) 423 { 424 va_list ap; 425 426 va_start(ap, fmt); 427 vwarnx(fmt, ap); 428 va_end(ap); 429 eval = 1; 430 } 431 432 static void 433 cwarn(const char *fmt, ...) 434 { 435 va_list ap; 436 437 va_start(ap, fmt); 438 vwarn(fmt, ap); 439 va_end(ap); 440 eval = 1; 441 } 442