compress/compress.c

   1 /*-
   2  * Copyright (c) 1992, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #ifndef lint
  35 static const char copyright[] =
  36 "@(#) Copyright (c) 1992, 1993\n\
  37         The Regents of the University of California.  All rights reserved.\n";
  38 #endif
  39
  40 #if 0
  41 #ifndef lint
  42 static char sccsid[] = "@(#)compress.c  8.2 (Berkeley) 1/7/94";
  43 #endif
  44 #endif
  45
  46 #include <sys/cdefs.h>
  47 __FBSDID("$FreeBSD: src/usr.bin/compress/compress.c,v 1.21 2003/06/14 13:41:31 trhodes Exp $");
  48
  49 #include <sys/param.h>
  50 #include <sys/stat.h>
  51 #include <sys/time.h>
  52
  53 #include <err.h>
  54 #include <errno.h>
  55 #include <stdarg.h>
  56 #include <stdio.h>
  57 #include <stdlib.h>
  58 #include <string.h>
  59 #include <unistd.h>
  60
  61 #include "zopen.h"
  62
  63 void    compress(const char *, const char *, int);
  64 void    cwarn(const char *, ...) __printflike(1, 2);
  65 void    cwarnx(const char *, ...) __printflike(1, 2);
  66 void    decompress(const char *, const char *, int);
  67 int     permission(const char *);
  68 void    setfile(const char *, struct stat *);
  69 void    usage(int);
  70
  71 int eval, force, verbose, cat;
  72
  73 int
  74 main(int argc, char *argv[])
  75 {
  76         enum {COMPRESS, DECOMPRESS} style;
  77         size_t len;
  78         int bits, ch;
  79         char *p, newname[MAXPATHLEN];
  80
  81         if (argc < 1)
  82                 usage(1);
  83         cat = 0;
  84         if ((p = rindex(argv[0], '/')) == NULL)
  85                 p = argv[0];
  86         else
  87                 ++p;
  88         if (!strcmp(p, "uncompress"))
  89                 style = DECOMPRESS;
  90         else if (!strcmp(p, "compress"))
  91                 style = COMPRESS;
  92         else if (!strcmp(p, "zcat")) {
  93                 cat = 1;
  94                 style = DECOMPRESS;
  95         } else
  96                 errx(1, "unknown program name");
  97
  98         bits = 0;
  99         while ((ch = getopt(argc, argv, "b:cdfv")) != -1)
 100                 switch(ch) {
 101                 case 'b':
 102                         bits = strtol(optarg, &p, 10);
 103                         if (*p)
 104                                 errx(1, "illegal bit count -- %s", optarg);
 105                         break;
 106                 case 'c':
 107                         cat = 1;
 108                         break;
 109                 case 'd':               /* Backward compatible. */
 110                         style = DECOMPRESS;
 111                         break;
 112                 case 'f':
 113                         force = 1;
 114                         break;
 115                 case 'v':
 116                         verbose = 1;
 117                         break;
 118                 case '?':
 119                 default:
 120                         usage(style == COMPRESS);
 121                 }
 122         argc -= optind;
 123         argv += optind;
 124
 125         if (argc == 0) {
 126                 cat = 1;
 127                 switch(style) {
 128                 case COMPRESS:
 129                         (void)compress("/dev/stdin", "/dev/stdout", bits);
 130                         break;
 131                 case DECOMPRESS:
 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                 switch(style) {
 143                 case COMPRESS:
 144                         if (strcmp(*argv, "-") == 0) {
 145                                 cat = 1;
 146                                 compress("/dev/stdin", "/dev/stdout", bits);
 147                                 break;
 148                         } else if (cat) {
 149                                 compress(*argv, "/dev/stdout", bits);
 150                                 break;
 151                         }
 152                         if ((p = rindex(*argv, '.')) != NULL &&
 153                             !strcmp(p, ".Z")) {
 154                                 cwarnx("%s: name already has trailing .Z",
 155                                     *argv);
 156                                 break;
 157                         }
 158                         len = strlen(*argv);
 159                         if (len > sizeof(newname) - 3) {
 160                                 cwarnx("%s: name too long", *argv);
 161                                 break;
 162                         }
 163                         memmove(newname, *argv, len);
 164                         newname[len] = '.';
 165                         newname[len + 1] = 'Z';
 166                         newname[len + 2] = '\0';
 167                         compress(*argv, newname, bits);
 168                         break;
 169                 case DECOMPRESS:
 170                         if (strcmp(*argv, "-") == 0) {
 171                                 cat = 1;
 172                                 decompress("/dev/stdin", "/dev/stdout", bits);
 173                                 break;
 174                         }
 175                         len = strlen(*argv);
 176                         if ((p = rindex(*argv, '.')) == NULL ||
 177                             strcmp(p, ".Z")) {
 178                                 if (len > sizeof(newname) - 3) {
 179                                         cwarnx("%s: name too long", *argv);
 180                                         break;
 181                                 }
 182                                 memmove(newname, *argv, len);
 183                                 newname[len] = '.';
 184                                 newname[len + 1] = 'Z';
 185                                 newname[len + 2] = '\0';
 186                                 decompress(newname,
 187                                     cat ? "/dev/stdout" : *argv, bits);
 188                         } else {
 189                                 if (len - 2 > sizeof(newname) - 1) {
 190                                         cwarnx("%s: name too long", *argv);
 191                                         break;
 192                                 }
 193                                 memmove(newname, *argv, len - 2);
 194                                 newname[len - 2] = '\0';
 195                                 decompress(*argv,
 196                                     cat ? "/dev/stdout" : newname, bits);
 197                         }
 198                         break;
 199                 }
 200         exit (eval);
 201 }
 202
 203 void
 204 compress(const char *in, const char *out, int bits)
 205 {
 206         size_t nr;
 207         struct stat isb, sb;
 208         FILE *ifp, *ofp;
 209         int exists, isreg, oreg;
 210         u_char buf[1024];
 211
 212         exists = !stat(out, &sb);
 213         if (!force && exists && S_ISREG(sb.st_mode) && !cat && !permission(out)) {
 214                 cwarnx("%s already exists", out);
 215                 return;
 216         }
 217         isreg = oreg = !exists || S_ISREG(sb.st_mode);
 218
 219         ifp = ofp = NULL;
 220         if ((ifp = fopen(in, "r")) == NULL) {
 221                 cwarn("%s", in);
 222                 return;
 223         }
 224         if (stat(in, &isb)) {           /* DON'T FSTAT! */
 225                 cwarn("%s", in);
 226                 goto err;
 227         }
 228         if (!S_ISREG(isb.st_mode))
 229                 isreg = 0;
 230
 231         if ((ofp = zopen(out, "w", bits)) == NULL) {
 232                 cwarn("%s", out);
 233                 goto err;
 234         }
 235         while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0)
 236                 if (fwrite(buf, 1, nr, ofp) != nr) {
 237                         cwarn("%s", out);
 238                         goto err;
 239                 }
 240
 241         if (ferror(ifp) || fclose(ifp)) {
 242                 cwarn("%s", in);
 243                 goto err;
 244         }
 245         ifp = NULL;
 246
 247         if (fclose(ofp)) {
 248                 cwarn("%s", out);
 249                 goto err;
 250         }
 251         ofp = NULL;
 252
 253         if (!cat && isreg) {
 254                 if (stat(out, &sb)) {
 255                         cwarn("%s", out);
 256                         goto err;
 257                 }
 258
 259                 if (!force && sb.st_size >= isb.st_size) {
 260                         if (verbose)
 261                 (void)fprintf(stderr, "%s: file would grow; left unmodified\n",
 262                     in);
 263                         eval = 2;
 264                         if (unlink(out))
 265                                 cwarn("%s", out);
 266                         goto err;
 267                 }
 268
 269                 setfile(out, &isb);
 270
 271                 if (unlink(in))
 272                         cwarn("%s", in);
 273
 274                 if (verbose) {
 275                         (void)fprintf(stderr, "%s: ", out);
 276                         if (isb.st_size > sb.st_size)
 277                                 (void)fprintf(stderr, "%.0f%% compression\n",
 278                                     ((float)sb.st_size / isb.st_size) * 100.0);
 279                         else
 280                                 (void)fprintf(stderr, "%.0f%% expansion\n",
 281                                     ((float)isb.st_size / sb.st_size) * 100.0);
 282                 }
 283         }
 284         return;
 285
 286 err:    if (ofp) {
 287                 if (!cat && oreg)
 288                         (void)unlink(out);
 289                 (void)fclose(ofp);
 290         }
 291         if (ifp)
 292                 (void)fclose(ifp);
 293 }
 294
 295 void
 296 decompress(const char *in, const char *out, int bits)
 297 {
 298         size_t nr;
 299         struct stat sb;
 300         FILE *ifp, *ofp;
 301         int exists, isreg, oreg;
 302         u_char buf[1024];
 303
 304         exists = !stat(out, &sb);
 305         if (!force && exists && S_ISREG(sb.st_mode) && !cat && !permission(out)) {
 306                 cwarnx("%s already exists", out);
 307                 return;
 308         }
 309         isreg = oreg = !exists || S_ISREG(sb.st_mode);
 310
 311         ifp = ofp = NULL;
 312         if ((ifp = zopen(in, "r", bits)) == NULL) {
 313                 cwarn("%s", in);
 314                 return;
 315         }
 316         if (stat(in, &sb)) {
 317                 cwarn("%s", in);
 318                 goto err;
 319         }
 320         if (!S_ISREG(sb.st_mode))
 321                 isreg = 0;
 322
 323         /*
 324          * Try to read the first few uncompressed bytes from the input file
 325          * before blindly truncating the output file.
 326          */
 327         if ((nr = fread(buf, 1, sizeof(buf), ifp)) == 0) {
 328                 cwarn("%s", in);
 329                 (void)fclose(ifp);
 330                 return;
 331         }
 332         if ((ofp = fopen(out, "w")) == NULL ||
 333             (nr != 0 && fwrite(buf, 1, nr, ofp) != nr)) {
 334                 cwarn("%s", out);
 335                 (void)fclose(ifp);
 336                 return;
 337         }
 338
 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) || fclose(ifp)) {
 346                 cwarn("%s", in);
 347                 goto err;
 348         }
 349         ifp = NULL;
 350
 351         if (fclose(ofp)) {
 352                 cwarn("%s", out);
 353                 goto err;
 354         }
 355
 356         if (!cat && isreg) {
 357                 setfile(out, &sb);
 358
 359                 if (unlink(in))
 360                         cwarn("%s", in);
 361                 if (verbose) {
 362                         struct stat isb = sb;
 363                         stat(out, &sb);
 364                         (void)fprintf(stderr, "%s: ", out);
 365                         if (isb.st_size > sb.st_size)
 366                                 (void)fprintf(stderr, "%.0f%% compression\n",
 367                                     ((float)sb.st_size / isb.st_size) * 100.0);
 368                         else
 369                                 (void)fprintf(stderr, "%.0f%% expansion\n",
 370                                     ((float)isb.st_size / sb.st_size) * 100.0);
 371                 }
 372         }
 373         return;
 374
 375 err:    if (ofp) {
 376                 if (!cat && oreg)
 377                         (void)unlink(out);
 378                 (void)fclose(ofp);
 379         }
 380         if (ifp)
 381                 (void)fclose(ifp);
 382 }
 383
 384 void
 385 setfile(const char *name, struct stat *fs)
 386 {
 387         static struct timeval tv[2];
 388
 389         fs->st_mode &= S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO;
 390
 391         TIMESPEC_TO_TIMEVAL(&tv[0], &fs->st_atimespec);
 392         TIMESPEC_TO_TIMEVAL(&tv[1], &fs->st_mtimespec);
 393         if (utimes(name, tv))
 394                 cwarn("utimes: %s", name);
 395
 396         /*
 397          * Changing the ownership probably won't succeed, unless we're root
 398          * or POSIX_CHOWN_RESTRICTED is not set.  Set uid/gid before setting
 399          * the mode; current BSD behavior is to remove all setuid bits on
 400          * chown.  If chown fails, lose setuid/setgid bits.
 401          */
 402         if (chown(name, fs->st_uid, fs->st_gid)) {
 403                 if (errno != EPERM)
 404                         cwarn("chown: %s", name);
 405                 fs->st_mode &= ~(S_ISUID|S_ISGID);
 406         }
 407         if (chmod(name, fs->st_mode) && errno != ENOTSUP)
 408                 cwarn("chmod: %s", name);
 409
 410         if (chflags(name, fs->st_flags) && errno != ENOTSUP)
 411                 cwarn("chflags: %s", name);
 412 }
 413
 414 int
 415 permission(const 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 [-cfv] [-b bits] [file ...]\n");
 434         else
 435                 (void)fprintf(stderr,
 436                     "usage: uncompress [-cfv] [-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 }