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