compress/compress.c

   1 /*      $NetBSD: compress.c,v 1.16 1998/03/10 12:45:44 kleink 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. All advertising materials mentioning features or use of this software
  16  *    must display the following acknowledgement:
  17  *      This product includes software developed by the University of
  18  *      California, Berkeley and its contributors.
  19  * 4. Neither the name of the University nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  */
  35
  36 #include <sys/cdefs.h>
  37 #ifndef lint
  38 __COPYRIGHT("@(#) Copyright (c) 1992, 1993\n\
  39         The Regents of the University of California.  All rights reserved.\n");
  40 #endif /* not lint */
  41
  42 #ifndef lint
  43 #if 0
  44 static char sccsid[] = "@(#)compress.c  8.2 (Berkeley) 1/7/94";
  45 #else
  46 __RCSID("$NetBSD: compress.c,v 1.16 1998/03/10 12:45:44 kleink Exp $");
  47 #endif
  48 #endif /* not lint */
  49
  50 #include <sys/param.h>
  51 #include <sys/time.h>
  52 #include <sys/stat.h>
  53
  54 #include <err.h>
  55 #include <errno.h>
  56 #include <stdio.h>
  57 #include <stdlib.h>
  58 #include <string.h>
  59 #include <unistd.h>
  60
  61 #ifdef __STDC__
  62 #include <stdarg.h>
  63 #else
  64 #include <varargs.h>
  65 #endif
  66
  67 void    compress __P((char *, char *, int));
  68 void    cwarn __P((const char *, ...));
  69 void    cwarnx __P((const char *, ...));
  70 void    decompress __P((char *, char *, int));
  71 int     permission __P((char *));
  72 void    setfile __P((char *, struct stat *));
  73 void    usage __P((int));
  74
  75 int     main __P((int, char *[]));
  76 extern FILE *zopen __P((const char *fname, const char *mode, int bits));
  77
  78 int eval, force, verbose;
  79 int isstdout, isstdin;
  80
  81 int
  82 main(argc, argv)
  83         int argc;
  84         char *argv[];
  85 {
  86         enum {COMPRESS, DECOMPRESS} style = COMPRESS;
  87         size_t len;
  88         int bits, cat, ch;
  89         char *p, newname[MAXPATHLEN];
  90
  91         if ((p = strrchr(argv[0], '/')) == NULL)
  92                 p = argv[0];
  93         else
  94                 ++p;
  95         if (!strcmp(p, "uncompress"))
  96                 style = DECOMPRESS;
  97         else if (!strcmp(p, "compress"))
  98                 style = COMPRESS;
  99         else if (!strcmp(p, "zcat")) {
 100                 style = DECOMPRESS;
 101                 cat = 1;
 102         }
 103         else
 104                 errx(1, "unknown program name");
 105
 106         bits = cat = 0;
 107         while ((ch = getopt(argc, argv, "b:cdfv")) != -1)
 108                 switch(ch) {
 109                 case 'b':
 110                         bits = strtol(optarg, &p, 10);
 111                         if (*p)
 112                                 errx(1, "illegal bit count -- %s", optarg);
 113                         break;
 114                 case 'c':
 115                         cat = 1;
 116                         break;
 117                 case 'd':               /* Backward compatible. */
 118                         style = DECOMPRESS;
 119                         break;
 120                 case 'f':
 121                         force = 1;
 122                         break;
 123                 case 'v':
 124                         verbose = 1;
 125                         break;
 126                 case '?':
 127                 default:
 128                         usage(style == COMPRESS);
 129                 }
 130         argc -= optind;
 131         argv += optind;
 132
 133         if (argc == 0) {
 134                 switch(style) {
 135                 case COMPRESS:
 136                         isstdout = 1;
 137                         isstdin = 1;
 138                         (void)compress("/dev/stdin", "/dev/stdout", bits);
 139                         break;
 140                 case DECOMPRESS:
 141                         isstdout = 1;
 142                         isstdin = 1;
 143                         (void)decompress("/dev/stdin", "/dev/stdout", bits);
 144                         break;
 145                 }
 146                 exit (eval);
 147         }
 148
 149         if (cat == 1 && argc > 1)
 150                 errx(1, "the -c option permits only a single file argument");
 151
 152         for (; *argv; ++argv) {
 153                 isstdout = 0;
 154                 switch(style) {
 155                 case COMPRESS:
 156                         if (cat) {
 157                                 isstdout = 1;
 158                                 compress(*argv, "/dev/stdout", bits);
 159                                 break;
 160                         }
 161                         if ((p = strrchr(*argv, '.')) != NULL &&
 162                             !strcmp(p, ".Z")) {
 163                                 cwarnx("%s: name already has trailing .Z",
 164                                     *argv);
 165                                 break;
 166                         }
 167                         len = strlen(*argv);
 168                         if (len > sizeof(newname) - 3) {
 169                                 cwarnx("%s: name too long", *argv);
 170                                 break;
 171                         }
 172                         memmove(newname, *argv, len);
 173                         newname[len] = '.';
 174                         newname[len + 1] = 'Z';
 175                         newname[len + 2] = '\0';
 176                         compress(*argv, newname, bits);
 177                         break;
 178                 case DECOMPRESS:
 179                         len = strlen(*argv);
 180                         if ((p = strrchr(*argv, '.')) == NULL ||
 181                             strcmp(p, ".Z")) {
 182                                 if (len > sizeof(newname) - 3) {
 183                                         cwarnx("%s: name too long", *argv);
 184                                         break;
 185                                 }
 186                                 memmove(newname, *argv, len);
 187                                 newname[len] = '.';
 188                                 newname[len + 1] = 'Z';
 189                                 newname[len + 2] = '\0';
 190                                 decompress(newname,
 191                                     cat ? "/dev/stdout" : *argv, bits);
 192                                 if (cat)
 193                                         isstdout = 1;
 194                         } else {
 195                                 if (len - 2 > sizeof(newname) - 1) {
 196                                         cwarnx("%s: name too long", *argv);
 197                                         break;
 198                                 }
 199                                 memmove(newname, *argv, len - 2);
 200                                 newname[len - 2] = '\0';
 201                                 decompress(*argv,
 202                                     cat ? "/dev/stdout" : newname, bits);
 203                                 if (cat)
 204                                         isstdout = 1;
 205                         }
 206                         break;
 207                 }
 208         }
 209         exit (eval);
 210 }
 211
 212 void
 213 compress(in, out, bits)
 214         char *in, *out;
 215         int bits;
 216 {
 217         int nr;
 218         struct stat isb, sb;
 219         FILE *ifp, *ofp;
 220         int exists, isreg, oreg;
 221         u_char buf[BUFSIZ];
 222
 223         if (!isstdout) {
 224                 exists = !stat(out, &sb);
 225                 if (!force && exists && S_ISREG(sb.st_mode) && !permission(out))
 226                         return;
 227                 oreg = !exists || S_ISREG(sb.st_mode);
 228         } else
 229                 oreg = 0;
 230
 231         ifp = ofp = NULL;
 232         if ((ifp = fopen(in, "r")) == NULL) {
 233                 cwarn("%s", in);
 234                 return;
 235         }
 236
 237         if (!isstdin) {
 238                 if (stat(in, &isb)) {           /* DON'T FSTAT! */
 239                         cwarn("%s", in);
 240                         goto err;
 241                 }
 242                 if (!S_ISREG(isb.st_mode))
 243                         isreg = 0;
 244                 else
 245                         isreg = 1;
 246         } else
 247                 isreg = 0;
 248
 249         if ((ofp = zopen(out, "w", bits)) == NULL) {
 250                 cwarn("%s", out);
 251                 goto err;
 252         }
 253         while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0)
 254                 if (fwrite(buf, 1, nr, ofp) != nr) {
 255                         cwarn("%s", out);
 256                         goto err;
 257                 }
 258
 259         if (ferror(ifp) || fclose(ifp)) {
 260                 cwarn("%s", in);
 261                 goto err;
 262         }
 263         ifp = NULL;
 264
 265         if (fclose(ofp)) {
 266                 cwarn("%s", out);
 267                 goto err;
 268         }
 269         ofp = NULL;
 270
 271         if (isreg && oreg) {
 272                 if (stat(out, &sb)) {
 273                         cwarn("%s", out);
 274                         goto err;
 275                 }
 276
 277                 if (!force && sb.st_size >= isb.st_size) {
 278                         if (verbose)
 279                 (void)printf("%s: file would grow; left unmodified\n", in);
 280                         if (unlink(out))
 281                                 cwarn("%s", out);
 282                         goto err;
 283                 }
 284
 285                 setfile(out, &isb);
 286
 287                 if (unlink(in))
 288                         cwarn("%s", in);
 289
 290                 if (verbose) {
 291                         (void)printf("%s: ", out);
 292                         if (isb.st_size > sb.st_size)
 293                                 (void)printf("%.0f%% compression\n",
 294                                     ((double)sb.st_size / isb.st_size) * 100.0);
 295                         else
 296                                 (void)printf("%.0f%% expansion\n",
 297                                     ((double)isb.st_size / sb.st_size) * 100.0);
 298                 }
 299         }
 300         return;
 301
 302 err:    if (ofp) {
 303                 if (oreg)
 304                         (void)unlink(out);
 305                 (void)fclose(ofp);
 306         }
 307         if (ifp)
 308                 (void)fclose(ifp);
 309 }
 310
 311 void
 312 decompress(in, out, bits)
 313         char *in, *out;
 314         int bits;
 315 {
 316         int nr;
 317         struct stat sb;
 318         FILE *ifp, *ofp;
 319         int exists, isreg, oreg;
 320         u_char buf[BUFSIZ];
 321
 322         if (!isstdout) {
 323                 exists = !stat(out, &sb);
 324                 if (!force && exists && S_ISREG(sb.st_mode) && !permission(out))
 325                         return;
 326                 oreg = !exists || S_ISREG(sb.st_mode);
 327         } else
 328                 oreg = 0;
 329
 330         ifp = ofp = NULL;
 331         if ((ofp = fopen(out, "w")) == NULL) {
 332                 cwarn("%s", out);
 333                 return;
 334         }
 335
 336         if ((ifp = zopen(in, "r", bits)) == NULL) {
 337                 cwarn("%s", in);
 338                 goto err;
 339         }
 340         if (!isstdin) {
 341                 if (stat(in, &sb)) {
 342                         cwarn("%s", in);
 343                         goto err;
 344                 }
 345                 if (!S_ISREG(sb.st_mode))
 346                         isreg = 0;
 347                 else
 348                         isreg = 1;
 349         } else
 350                 isreg = 0;
 351
 352         while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0)
 353                 if (fwrite(buf, 1, nr, ofp) != nr) {
 354                         cwarn("%s", out);
 355                         goto err;
 356                 }
 357
 358         if (ferror(ifp) || fclose(ifp)) {
 359                 cwarn("%s", in);
 360                 goto err;
 361         }
 362         ifp = NULL;
 363
 364         if (fclose(ofp)) {
 365                 cwarn("%s", out);
 366                 goto err;
 367         }
 368
 369         if (isreg && oreg) {
 370                 setfile(out, &sb);
 371
 372                 if (unlink(in))
 373                         cwarn("%s", in);
 374         }
 375         return;
 376
 377 err:    if (ofp) {
 378                 if (oreg)
 379                         (void)unlink(out);
 380                 (void)fclose(ofp);
 381         }
 382         if (ifp)
 383                 (void)fclose(ifp);
 384 }
 385
 386 void
 387 setfile(name, fs)
 388         char *name;
 389         struct stat *fs;
 390 {
 391         static struct timeval tv[2];
 392
 393         fs->st_mode &= S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO;
 394
 395         TIMESPEC_TO_TIMEVAL(&tv[0], &fs->st_atimespec);
 396         TIMESPEC_TO_TIMEVAL(&tv[1], &fs->st_mtimespec);
 397         if (utimes(name, tv))
 398                 cwarn("utimes: %s", name);
 399
 400         /*
 401          * Changing the ownership probably won't succeed, unless we're root
 402          * or POSIX_CHOWN_RESTRICTED is not set.  Set uid/gid before setting
 403          * the mode; current BSD behavior is to remove all setuid bits on
 404          * chown.  If chown fails, lose setuid/setgid bits.
 405          */
 406         if (chown(name, fs->st_uid, fs->st_gid)) {
 407                 if (errno != EPERM)
 408                         cwarn("chown: %s", name);
 409                 fs->st_mode &= ~(S_ISUID|S_ISGID);
 410         }
 411         if (chmod(name, fs->st_mode))
 412                 cwarn("chown: %s", name);
 413
 414         /*
 415          * Restore the file's flags.  However, do this only if the original
 416          * file had any flags set; this avoids a warning on file-systems that
 417          * do not support flags.
 418          */
 419         if (fs->st_flags != 0 && chflags(name, fs->st_flags))
 420                 cwarn("chflags: %s", name);
 421 }
 422
 423 int
 424 permission(fname)
 425         char *fname;
 426 {
 427         int ch, first;
 428
 429         if (!isatty(fileno(stderr)))
 430                 return (0);
 431         (void)fprintf(stderr, "overwrite %s? ", fname);
 432         first = ch = getchar();
 433         while (ch != '\n' && ch != EOF)
 434                 ch = getchar();
 435         return (first == 'y');
 436 }
 437
 438 void
 439 usage(iscompress)
 440         int iscompress;
 441 {
 442         if (iscompress)
 443                 (void)fprintf(stderr,
 444                     "usage: compress [-cfv] [-b bits] [file ...]\n");
 445         else
 446                 (void)fprintf(stderr,
 447                     "usage: uncompress [-c] [-b bits] [file ...]\n");
 448         exit(1);
 449 }
 450
 451 void
 452 #if __STDC__
 453 cwarnx(const char *fmt, ...)
 454 #else
 455 cwarnx(fmt, va_alist)
 456         int eval;
 457         const char *fmt;
 458         va_dcl
 459 #endif
 460 {
 461         va_list ap;
 462 #if __STDC__
 463         va_start(ap, fmt);
 464 #else
 465         va_start(ap);
 466 #endif
 467         vwarnx(fmt, ap);
 468         va_end(ap);
 469         eval = 1;
 470 }
 471
 472 void
 473 #if __STDC__
 474 cwarn(const char *fmt, ...)
 475 #else
 476 cwarn(fmt, va_alist)
 477         int eval;
 478         const char *fmt;
 479         va_dcl
 480 #endif
 481 {
 482         va_list ap;
 483 #if __STDC__
 484         va_start(ap, fmt);
 485 #else
 486         va_start(ap);
 487 #endif
 488         vwarn(fmt, ap);
 489         va_end(ap);
 490         eval = 1;
 491 }