1 /* $NetBSD: compress.c,v 1.26 2011/08/30 23:08:05 joerg Exp $ */ 2 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 #include <sys/cdefs.h> 33 #ifndef lint 34 __COPYRIGHT("@(#) Copyright (c) 1992, 1993\ 35 The Regents of the University of California. All rights reserved."); 36 #endif /* not lint */ 37 38 #ifndef lint 39 #if 0 40 static char sccsid[] = "@(#)compress.c 8.2 (Berkeley) 1/7/94"; 41 #else 42 __RCSID("$NetBSD: compress.c,v 1.26 2011/08/30 23:08:05 joerg Exp $"); 43 #endif 44 #endif /* not lint */ 45 46 #include <sys/param.h> 47 #include <sys/time.h> 48 #include <sys/stat.h> 49 50 #include <err.h> 51 #include <errno.h> 52 #include <stdarg.h> 53 #include <stdio.h> 54 #include <stdlib.h> 55 #include <string.h> 56 #include <unistd.h> 57 58 static void compress(const char *, const char *, int); 59 static void cwarn(const char *, ...) __printflike(1, 2); 60 static void cwarnx(const char *, ...) __printflike(1, 2); 61 static void decompress(const char *, const char *, int); 62 static int permission(const char *); 63 static void setfile(const char *, struct stat *); 64 __dead static void usage(int); 65 66 extern FILE *zopen(const char *fname, const char *mode, int bits); 67 68 static int eval, force, verbose; 69 static int isstdout, isstdin; 70 71 int 72 main(int argc, char **argv) 73 { 74 enum {COMPRESS, DECOMPRESS} style = COMPRESS; 75 size_t len; 76 int bits, cat, ch; 77 char *p, newname[MAXPATHLEN]; 78 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 style = DECOMPRESS; 89 cat = 1; 90 } 91 else 92 errx(1, "unknown program name"); 93 94 bits = cat = 0; 95 while ((ch = getopt(argc, argv, "b:cdfv")) != -1) 96 switch(ch) { 97 case 'b': 98 bits = strtol(optarg, &p, 10); 99 if (*p) 100 errx(1, "illegal bit count -- %s", optarg); 101 break; 102 case 'c': 103 cat = 1; 104 break; 105 case 'd': /* Backward compatible. */ 106 style = DECOMPRESS; 107 break; 108 case 'f': 109 force = 1; 110 break; 111 case 'v': 112 verbose = 1; 113 break; 114 case '?': 115 default: 116 usage(style == COMPRESS); 117 } 118 argc -= optind; 119 argv += optind; 120 121 if (argc == 0) { 122 switch(style) { 123 case COMPRESS: 124 isstdout = 1; 125 isstdin = 1; 126 (void)compress("/dev/stdin", "/dev/stdout", bits); 127 break; 128 case DECOMPRESS: 129 isstdout = 1; 130 isstdin = 1; 131 (void)decompress("/dev/stdin", "/dev/stdout", bits); 132 break; 133 } 134 exit (eval); 135 } 136 137 if (cat == 1 && argc > 1) 138 errx(1, "the -c option permits only a single file argument"); 139 140 for (; *argv; ++argv) { 141 isstdout = 0; 142 switch(style) { 143 case COMPRESS: 144 if (cat) { 145 isstdout = 1; 146 compress(*argv, "/dev/stdout", bits); 147 break; 148 } 149 if ((p = strrchr(*argv, '.')) != NULL && 150 !strcmp(p, ".Z")) { 151 cwarnx("%s: name already has trailing .Z", 152 *argv); 153 break; 154 } 155 len = strlen(*argv); 156 if (len > sizeof(newname) - 3) { 157 cwarnx("%s: name too long", *argv); 158 break; 159 } 160 memmove(newname, *argv, len); 161 newname[len] = '.'; 162 newname[len + 1] = 'Z'; 163 newname[len + 2] = '\0'; 164 compress(*argv, newname, bits); 165 break; 166 case DECOMPRESS: 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 if (cat) 181 isstdout = 1; 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 if (cat) 192 isstdout = 1; 193 } 194 break; 195 } 196 } 197 exit (eval); 198 } 199 200 static void 201 compress(const char *in, const char *out, int bits) 202 { 203 size_t nr; 204 struct stat isb, sb; 205 const char *error = NULL; 206 FILE *ifp, *ofp; 207 int exists, isreg, oreg; 208 u_char buf[BUFSIZ]; 209 210 if (!isstdout) { 211 exists = !stat(out, &sb); 212 if (!force && exists && S_ISREG(sb.st_mode) && !permission(out)) 213 return; 214 oreg = !exists || S_ISREG(sb.st_mode); 215 } else 216 oreg = 0; 217 218 ifp = ofp = NULL; 219 if ((ifp = fopen(in, "r")) == NULL) { 220 cwarn("%s", in); 221 return; 222 } 223 224 if (!isstdin) { 225 if (stat(in, &isb)) { /* DON'T FSTAT! */ 226 cwarn("%s", in); 227 goto err; 228 } 229 if (!S_ISREG(isb.st_mode)) 230 isreg = 0; 231 else 232 isreg = 1; 233 } else 234 isreg = 0; 235 236 if ((ofp = zopen(out, "w", bits)) == NULL) { 237 cwarn("%s", out); 238 goto err; 239 } 240 oreg <<= 1; 241 while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0) 242 if (fwrite(buf, 1, nr, ofp) != nr) { 243 cwarn("%s", out); 244 goto err; 245 } 246 247 if (ferror(ifp)) 248 error = in; 249 if (fclose(ifp)) 250 if (error == NULL) 251 error = in; 252 if (fclose(ofp)) 253 if (error == NULL) 254 error = out; 255 ifp = NULL; 256 ofp = NULL; 257 if (error) { 258 cwarn("%s", error); 259 goto err; 260 } 261 262 if (isreg && oreg) { 263 if (stat(out, &sb)) { 264 cwarn("%s", out); 265 goto err; 266 } 267 268 if (!force && sb.st_size >= isb.st_size) { 269 if (verbose) 270 (void)printf("%s: file would grow; left unmodified\n", in); 271 goto err; 272 } 273 274 setfile(out, &isb); 275 276 if (unlink(in)) 277 cwarn("%s", in); 278 279 if (verbose) { 280 (void)printf("%s: ", out); 281 if (isb.st_size > sb.st_size) 282 (void)printf("%.0f%% compression\n", 283 ((double)sb.st_size / isb.st_size) * 100.0); 284 else 285 (void)printf("%.0f%% expansion\n", 286 ((double)isb.st_size / sb.st_size) * 100.0); 287 } 288 } 289 return; 290 291 err: if (ofp) 292 (void)fclose(ofp); 293 if (oreg == 2) 294 (void)unlink(out); 295 if (ifp) 296 (void)fclose(ifp); 297 } 298 299 static void 300 decompress(const char *in, const char *out, int bits) 301 { 302 size_t nr; 303 struct stat sb; 304 FILE *ifp, *ofp; 305 int exists, isreg, oreg; 306 u_char buf[BUFSIZ]; 307 308 if (!isstdout) { 309 exists = !stat(out, &sb); 310 if (!force && exists && S_ISREG(sb.st_mode) && !permission(out)) 311 return; 312 oreg = !exists || S_ISREG(sb.st_mode); 313 } else 314 oreg = 0; 315 316 ifp = ofp = NULL; 317 if ((ofp = fopen(out, "w")) == NULL) { 318 cwarn("%s", out); 319 return; 320 } 321 322 if ((ifp = zopen(in, "r", bits)) == NULL) { 323 cwarn("%s", in); 324 goto err; 325 } 326 if (!isstdin) { 327 if (stat(in, &sb)) { 328 cwarn("%s", in); 329 goto err; 330 } 331 if (!S_ISREG(sb.st_mode)) 332 isreg = 0; 333 else 334 isreg = 1; 335 } else 336 isreg = 0; 337 338 oreg <<= 1; 339 while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0) 340 if (fwrite(buf, 1, nr, ofp) != nr) { 341 cwarn("%s", out); 342 goto err; 343 } 344 345 if (ferror(ifp)) { 346 cwarn("%s", in); 347 goto err; 348 } 349 if (fclose(ifp)) { 350 ifp = NULL; 351 cwarn("%s", in); 352 goto err; 353 } 354 ifp = NULL; 355 356 if (fclose(ofp)) { 357 ofp = NULL; 358 cwarn("%s", out); 359 goto err; 360 } 361 362 if (isreg && oreg) { 363 setfile(out, &sb); 364 365 if (unlink(in)) 366 cwarn("%s", in); 367 } 368 return; 369 370 err: if (ofp) 371 (void)fclose(ofp); 372 if (oreg == 2) 373 (void)unlink(out); 374 if (ifp) 375 (void)fclose(ifp); 376 } 377 378 static void 379 setfile(const char *name, struct stat *fs) 380 { 381 static struct timeval tv[2]; 382 383 fs->st_mode &= S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO; 384 385 TIMESPEC_TO_TIMEVAL(&tv[0], &fs->st_atimespec); 386 TIMESPEC_TO_TIMEVAL(&tv[1], &fs->st_mtimespec); 387 if (utimes(name, tv)) 388 cwarn("utimes: %s", name); 389 390 /* 391 * Changing the ownership probably won't succeed, unless we're root 392 * or POSIX_CHOWN_RESTRICTED is not set. Set uid/gid before setting 393 * the mode; current BSD behavior is to remove all setuid bits on 394 * chown. If chown fails, lose setuid/setgid bits. 395 */ 396 if (chown(name, fs->st_uid, fs->st_gid)) { 397 if (errno != EPERM) 398 cwarn("chown: %s", name); 399 fs->st_mode &= ~(S_ISUID|S_ISGID); 400 } 401 if (chmod(name, fs->st_mode)) 402 cwarn("chown: %s", name); 403 404 /* 405 * Restore the file's flags. However, do this only if the original 406 * file had any flags set; this avoids a warning on file-systems that 407 * do not support flags. 408 */ 409 if (fs->st_flags != 0 && chflags(name, fs->st_flags)) 410 cwarn("chflags: %s", name); 411 } 412 413 static int 414 permission(const char *fname) 415 { 416 int ch, first; 417 418 if (!isatty(fileno(stderr))) 419 return (0); 420 (void)fprintf(stderr, "overwrite %s? ", fname); 421 first = ch = getchar(); 422 while (ch != '\n' && ch != EOF) 423 ch = getchar(); 424 return (first == 'y'); 425 } 426 427 static void 428 usage(int iscompress) 429 { 430 if (iscompress) 431 (void)fprintf(stderr, 432 "usage: compress [-cdfv] [-b bits] [file ...]\n"); 433 else 434 (void)fprintf(stderr, 435 "usage: uncompress [-cdfv] [-b bits] [file ...]\n"); 436 exit(1); 437 } 438 439 static void 440 cwarnx(const char *fmt, ...) 441 { 442 va_list ap; 443 444 va_start(ap, fmt); 445 vwarnx(fmt, ap); 446 va_end(ap); 447 eval = 1; 448 } 449 450 static void 451 cwarn(const char *fmt, ...) 452 { 453 va_list ap; 454 455 va_start(ap, fmt); 456 vwarn(fmt, ap); 457 va_end(ap); 458 eval = 1; 459 } 460