1 /* $NetBSD: compress.c,v 1.23 2006/04/09 20:01:40 christos 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\n\ 35 The Regents of the University of California. All rights reserved.\n"); 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 1.23 2006/04/09 20:01:40 christos 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 void compress(char *, char *, int); 59 void cwarn(const char *, ...) __attribute__((__format__(__printf__,1,2))); 60 void cwarnx(const char *, ...) __attribute__((__format__(__printf__,1,2))); 61 void decompress(char *, char *, int); 62 int permission(char *); 63 void setfile(char *, struct stat *); 64 void usage(int); 65 66 int main(int, char *[]); 67 extern FILE *zopen(const char *fname, const char *mode, int bits); 68 69 int eval, force, verbose; 70 int isstdout, isstdin; 71 72 int 73 main(int argc, char **argv) 74 { 75 enum {COMPRESS, DECOMPRESS} style = COMPRESS; 76 size_t len; 77 int bits, cat, ch; 78 char *p, newname[MAXPATHLEN]; 79 80 if ((p = strrchr(argv[0], '/')) == NULL) 81 p = argv[0]; 82 else 83 ++p; 84 if (!strcmp(p, "uncompress")) 85 style = DECOMPRESS; 86 else if (!strcmp(p, "compress")) 87 style = COMPRESS; 88 else if (!strcmp(p, "zcat")) { 89 style = DECOMPRESS; 90 cat = 1; 91 } 92 else 93 errx(1, "unknown program name"); 94 95 bits = cat = 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 isstdout = 1; 126 isstdin = 1; 127 (void)compress("/dev/stdin", "/dev/stdout", bits); 128 break; 129 case DECOMPRESS: 130 isstdout = 1; 131 isstdin = 1; 132 (void)decompress("/dev/stdin", "/dev/stdout", bits); 133 break; 134 } 135 exit (eval); 136 } 137 138 if (cat == 1 && argc > 1) 139 errx(1, "the -c option permits only a single file argument"); 140 141 for (; *argv; ++argv) { 142 isstdout = 0; 143 switch(style) { 144 case COMPRESS: 145 if (cat) { 146 isstdout = 1; 147 compress(*argv, "/dev/stdout", bits); 148 break; 149 } 150 if ((p = strrchr(*argv, '.')) != NULL && 151 !strcmp(p, ".Z")) { 152 cwarnx("%s: name already has trailing .Z", 153 *argv); 154 break; 155 } 156 len = strlen(*argv); 157 if (len > sizeof(newname) - 3) { 158 cwarnx("%s: name too long", *argv); 159 break; 160 } 161 memmove(newname, *argv, len); 162 newname[len] = '.'; 163 newname[len + 1] = 'Z'; 164 newname[len + 2] = '\0'; 165 compress(*argv, newname, bits); 166 break; 167 case DECOMPRESS: 168 len = strlen(*argv); 169 if ((p = strrchr(*argv, '.')) == NULL || 170 strcmp(p, ".Z")) { 171 if (len > sizeof(newname) - 3) { 172 cwarnx("%s: name too long", *argv); 173 break; 174 } 175 memmove(newname, *argv, len); 176 newname[len] = '.'; 177 newname[len + 1] = 'Z'; 178 newname[len + 2] = '\0'; 179 decompress(newname, 180 cat ? "/dev/stdout" : *argv, bits); 181 if (cat) 182 isstdout = 1; 183 } else { 184 if (len - 2 > sizeof(newname) - 1) { 185 cwarnx("%s: name too long", *argv); 186 break; 187 } 188 memmove(newname, *argv, len - 2); 189 newname[len - 2] = '\0'; 190 decompress(*argv, 191 cat ? "/dev/stdout" : newname, bits); 192 if (cat) 193 isstdout = 1; 194 } 195 break; 196 } 197 } 198 exit (eval); 199 } 200 201 void 202 compress(char *in, char *out, int bits) 203 { 204 int nr; 205 struct stat isb, sb; 206 const char *error = NULL; 207 FILE *ifp, *ofp; 208 int exists, isreg, oreg; 209 u_char buf[BUFSIZ]; 210 211 if (!isstdout) { 212 exists = !stat(out, &sb); 213 if (!force && exists && S_ISREG(sb.st_mode) && !permission(out)) 214 return; 215 oreg = !exists || S_ISREG(sb.st_mode); 216 } else 217 oreg = 0; 218 219 ifp = ofp = NULL; 220 if ((ifp = fopen(in, "r")) == NULL) { 221 cwarn("%s", in); 222 return; 223 } 224 225 if (!isstdin) { 226 if (stat(in, &isb)) { /* DON'T FSTAT! */ 227 cwarn("%s", in); 228 goto err; 229 } 230 if (!S_ISREG(isb.st_mode)) 231 isreg = 0; 232 else 233 isreg = 1; 234 } else 235 isreg = 0; 236 237 if ((ofp = zopen(out, "w", bits)) == NULL) { 238 cwarn("%s", out); 239 goto err; 240 } 241 oreg <<= 1; 242 while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0) 243 if (fwrite(buf, 1, nr, ofp) != nr) { 244 cwarn("%s", out); 245 goto err; 246 } 247 248 if (ferror(ifp)) 249 error = in; 250 if (fclose(ifp)) 251 if (error == NULL) 252 error = in; 253 if (fclose(ofp)) 254 if (error == NULL) 255 error = out; 256 ifp = NULL; 257 ofp = NULL; 258 if (error) { 259 cwarn("%s", error); 260 goto err; 261 } 262 263 if (isreg && oreg) { 264 if (stat(out, &sb)) { 265 cwarn("%s", out); 266 goto err; 267 } 268 269 if (!force && sb.st_size >= isb.st_size) { 270 if (verbose) 271 (void)printf("%s: file would grow; left unmodified\n", in); 272 goto err; 273 } 274 275 setfile(out, &isb); 276 277 if (unlink(in)) 278 cwarn("%s", in); 279 280 if (verbose) { 281 (void)printf("%s: ", out); 282 if (isb.st_size > sb.st_size) 283 (void)printf("%.0f%% compression\n", 284 ((double)sb.st_size / isb.st_size) * 100.0); 285 else 286 (void)printf("%.0f%% expansion\n", 287 ((double)isb.st_size / sb.st_size) * 100.0); 288 } 289 } 290 return; 291 292 err: if (ofp) 293 (void)fclose(ofp); 294 if (oreg == 2) 295 (void)unlink(out); 296 if (ifp) 297 (void)fclose(ifp); 298 } 299 300 void 301 decompress(char *in, char *out, int bits) 302 { 303 int nr; 304 struct stat sb; 305 FILE *ifp, *ofp; 306 int exists, isreg, oreg; 307 u_char buf[BUFSIZ]; 308 309 if (!isstdout) { 310 exists = !stat(out, &sb); 311 if (!force && exists && S_ISREG(sb.st_mode) && !permission(out)) 312 return; 313 oreg = !exists || S_ISREG(sb.st_mode); 314 } else 315 oreg = 0; 316 317 ifp = ofp = NULL; 318 if ((ofp = fopen(out, "w")) == NULL) { 319 cwarn("%s", out); 320 return; 321 } 322 323 if ((ifp = zopen(in, "r", bits)) == NULL) { 324 cwarn("%s", in); 325 goto err; 326 } 327 if (!isstdin) { 328 if (stat(in, &sb)) { 329 cwarn("%s", in); 330 goto err; 331 } 332 if (!S_ISREG(sb.st_mode)) 333 isreg = 0; 334 else 335 isreg = 1; 336 } else 337 isreg = 0; 338 339 oreg <<= 1; 340 while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0) 341 if (fwrite(buf, 1, nr, ofp) != nr) { 342 cwarn("%s", out); 343 goto err; 344 } 345 346 if (ferror(ifp)) { 347 cwarn("%s", in); 348 goto err; 349 } 350 if (fclose(ifp)) { 351 ifp = NULL; 352 cwarn("%s", in); 353 goto err; 354 } 355 ifp = NULL; 356 357 if (fclose(ofp)) { 358 ofp = NULL; 359 cwarn("%s", out); 360 goto err; 361 } 362 363 if (isreg && oreg) { 364 setfile(out, &sb); 365 366 if (unlink(in)) 367 cwarn("%s", in); 368 } 369 return; 370 371 err: if (ofp) 372 (void)fclose(ofp); 373 if (oreg == 2) 374 (void)unlink(out); 375 if (ifp) 376 (void)fclose(ifp); 377 } 378 379 void 380 setfile(char *name, struct stat *fs) 381 { 382 static struct timeval tv[2]; 383 384 fs->st_mode &= S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO; 385 386 TIMESPEC_TO_TIMEVAL(&tv[0], &fs->st_atimespec); 387 TIMESPEC_TO_TIMEVAL(&tv[1], &fs->st_mtimespec); 388 if (utimes(name, tv)) 389 cwarn("utimes: %s", name); 390 391 /* 392 * Changing the ownership probably won't succeed, unless we're root 393 * or POSIX_CHOWN_RESTRICTED is not set. Set uid/gid before setting 394 * the mode; current BSD behavior is to remove all setuid bits on 395 * chown. If chown fails, lose setuid/setgid bits. 396 */ 397 if (chown(name, fs->st_uid, fs->st_gid)) { 398 if (errno != EPERM) 399 cwarn("chown: %s", name); 400 fs->st_mode &= ~(S_ISUID|S_ISGID); 401 } 402 if (chmod(name, fs->st_mode)) 403 cwarn("chown: %s", name); 404 405 /* 406 * Restore the file's flags. However, do this only if the original 407 * file had any flags set; this avoids a warning on file-systems that 408 * do not support flags. 409 */ 410 if (fs->st_flags != 0 && chflags(name, fs->st_flags)) 411 cwarn("chflags: %s", name); 412 } 413 414 int 415 permission(char *fname) 416 { 417 int ch, first; 418 419 if (!isatty(fileno(stderr))) 420 return (0); 421 (void)fprintf(stderr, "overwrite %s? ", fname); 422 first = ch = getchar(); 423 while (ch != '\n' && ch != EOF) 424 ch = getchar(); 425 return (first == 'y'); 426 } 427 428 void 429 usage(int iscompress) 430 { 431 if (iscompress) 432 (void)fprintf(stderr, 433 "usage: compress [-cdfv] [-b bits] [file ...]\n"); 434 else 435 (void)fprintf(stderr, 436 "usage: uncompress [-cdfv] [-b bits] [file ...]\n"); 437 exit(1); 438 } 439 440 void 441 cwarnx(const char *fmt, ...) 442 { 443 va_list ap; 444 445 va_start(ap, fmt); 446 vwarnx(fmt, ap); 447 va_end(ap); 448 eval = 1; 449 } 450 451 void 452 cwarn(const char *fmt, ...) 453 { 454 va_list ap; 455 456 va_start(ap, fmt); 457 vwarn(fmt, ap); 458 va_end(ap); 459 eval = 1; 460 } 461