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  * 4. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29
  30 #include <sys/cdefs.h>
  31 #ifndef lint
  32 __used static const char copyright[] =
  33 "@(#) Copyright (c) 1992, 1993\n\
  34         The Regents of the University of California.  All rights reserved.\n";
  35 #endif
  36
  37 #if 0
  38 #ifndef lint
  39 static char sccsid[] = "@(#)compress.c  8.2 (Berkeley) 1/7/94";
  40 #endif
  41 #endif
  42
  43 #include <sys/cdefs.h>
  44 __FBSDID("$FreeBSD: src/usr.bin/compress/compress.c,v 1.23 2010/12/11 08:32:16 joel Exp $");
  45
  46 #include <sys/param.h>
  47 #include <sys/stat.h>
  48 #include <sys/time.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 #include "zopen.h"
  59
  60 void    compress(const char *, const char *, int);
  61 void    cwarn(const char *, ...) __printflike(1, 2);
  62 void    cwarnx(const char *, ...) __printflike(1, 2);
  63 void    decompress(const char *, const char *, int);
  64 int     permission(const char *);
  65 void    setfile(const char *, struct stat *);
  66 void    usage(int);
  67
  68 int eval, force, verbose, cat;
  69
  70 int
  71 main(int argc, char *argv[])
  72 {
  73         enum {COMPRESS, DECOMPRESS} style;
  74         size_t len;
  75         int bits, ch;
  76         char *p, newname[MAXPATHLEN];
  77
  78         if (argc < 1)
  79                 usage(1);
  80         cat = 0;
  81         if ((p = rindex(argv[0], '/')) == NULL)
  82                 p = argv[0];
  83         else
  84                 ++p;
  85         if (!strcmp(p, "uncompress"))
  86                 style = DECOMPRESS;
  87         else if (!strcmp(p, "compress"))
  88                 style = COMPRESS;
  89         else if (!strcmp(p, "zcat")) {
  90                 cat = 1;
  91                 style = DECOMPRESS;
  92         } else
  93                 errx(1, "unknown program name");
  94
  95         bits = 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                 cat = 1;
 124                 switch(style) {
 125                 case COMPRESS:
 126                         (void)compress("/dev/stdin", "/dev/stdout", bits);
 127                         break;
 128                 case DECOMPRESS:
 129                         (void)decompress("/dev/stdin", "/dev/stdout", bits);
 130                         break;
 131                 }
 132                 exit (eval);
 133         }
 134
 135     /*
 136      * The UNIX standard requires that `uncompress -c` be able to have multiple file parameters given.
 137      */
 138
 139         for (; *argv; ++argv)
 140                 switch(style) {
 141                 case COMPRESS:
 142                         if (strcmp(*argv, "-") == 0) {
 143                                 cat = 1;
 144                                 compress("/dev/stdin", "/dev/stdout", bits);
 145                                 break;
 146                         } else if (cat) {
 147                                 compress(*argv, "/dev/stdout", bits);
 148                                 break;
 149                         }
 150                         if ((p = rindex(*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                         if (strcmp(*argv, "-") == 0) {
 169                                 cat = 1;
 170                                 decompress("/dev/stdin", "/dev/stdout", bits);
 171                                 break;
 172                         }
 173                         len = strlen(*argv);
 174                         if ((p = rindex(*argv, '.')) == NULL ||
 175                             strcmp(p, ".Z")) {
 176                                 if (len > sizeof(newname) - 3) {
 177                                         cwarnx("%s: name too long", *argv);
 178                                         break;
 179                                 }
 180                                 memmove(newname, *argv, len);
 181                                 newname[len] = '.';
 182                                 newname[len + 1] = 'Z';
 183                                 newname[len + 2] = '\0';
 184                                 decompress(newname,
 185                                     cat ? "/dev/stdout" : *argv, bits);
 186                         } else {
 187                                 if (len - 2 > sizeof(newname) - 1) {
 188                                         cwarnx("%s: name too long", *argv);
 189                                         break;
 190                                 }
 191                                 memmove(newname, *argv, len - 2);
 192                                 newname[len - 2] = '\0';
 193                                 decompress(*argv,
 194                                     cat ? "/dev/stdout" : newname, bits);
 195                         }
 196                         break;
 197                 }
 198         exit (eval);
 199 }
 200
 201 void
 202 compress(const char *in, const char *out, int bits)
 203 {
 204         size_t nr;
 205         struct stat isb, sb;
 206         FILE *ifp = NULL, *ofp = NULL;
 207         int exists, isreg, oreg;
 208         u_char buf[1024];
 209
 210         exists = !stat(out, &sb);
 211         if (!force && exists && S_ISREG(sb.st_mode) && !cat && !permission(out)) {
 212                 cwarnx("%s already exists", out);
 213                 return;
 214         }
 215         isreg = oreg = !exists || S_ISREG(sb.st_mode);
 216
 217         if ((ifp = fopen(in, "r")) == NULL) {
 218                 cwarn("%s", in);
 219                 return;
 220         }
 221         if (stat(in, &isb)) {           /* DON'T FSTAT! */
 222                 cwarn("%s", in);
 223                 goto err;
 224         }
 225         if (!S_ISREG(isb.st_mode))
 226                 isreg = 0;
 227
 228         if ((ofp = zopen(out, "w", bits)) == NULL) {
 229                 cwarn("%s", out);
 230                 goto err;
 231         }
 232         while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0)
 233                 if (fwrite(buf, 1, nr, ofp) != nr) {
 234                         cwarn("%s", out);
 235                         goto err;
 236                 }
 237
 238         if (ferror(ifp) || fclose(ifp)) {
 239                 cwarn("%s", in);
 240                 goto err;
 241         }
 242         ifp = NULL;
 243
 244         if (fclose(ofp)) {
 245                 cwarn("%s", out);
 246                 goto err;
 247         }
 248         ofp = NULL;
 249
 250         if (!cat && isreg) {
 251                 if (stat(out, &sb)) {
 252                         cwarn("%s", out);
 253                         goto err;
 254                 }
 255
 256                 if (!force && sb.st_size >= isb.st_size) {
 257                         if (verbose)
 258                 (void)fprintf(stderr, "%s: file would grow; left unmodified\n",
 259                     in);
 260                         eval = 2;
 261                         if (unlink(out))
 262                                 cwarn("%s", out);
 263                         goto err;
 264                 }
 265
 266                 setfile(out, &isb);
 267
 268                 if (unlink(in))
 269                         cwarn("%s", in);
 270
 271                 if (verbose) {
 272                         (void)fprintf(stderr, "%s: ", out);
 273                         if (isb.st_size > sb.st_size)
 274                                 (void)fprintf(stderr, "%.0f%% compression\n",
 275                                     ((float)sb.st_size / isb.st_size) * 100.0);
 276                         else
 277                                 (void)fprintf(stderr, "%.0f%% expansion\n",
 278                                     ((float)isb.st_size / sb.st_size) * 100.0);
 279                 }
 280         }
 281         return;
 282
 283 err:    if (ofp) {
 284                 if (!cat && oreg)
 285                         (void)unlink(out);
 286                 (void)fclose(ofp);
 287         }
 288         if (ifp)
 289                 (void)fclose(ifp);
 290 }
 291
 292 void
 293 decompress(const char *in, const char *out, int bits)
 294 {
 295         size_t nr;
 296         struct stat sb;
 297         FILE *ifp, *ofp;
 298         int exists, isreg, oreg;
 299         u_char buf[1024];
 300
 301         exists = !stat(out, &sb);
 302         if (!force && exists && S_ISREG(sb.st_mode) && !cat && !permission(out)) {
 303                 cwarnx("%s already exists", out);
 304                 return;
 305         }
 306         isreg = oreg = !exists || S_ISREG(sb.st_mode);
 307
 308         ofp = NULL;
 309         if ((ifp = zopen(in, "r", bits)) == NULL) {
 310                 cwarn("%s", in);
 311                 return;
 312         }
 313         if (stat(in, &sb)) {
 314                 cwarn("%s", in);
 315                 goto err;
 316         }
 317         if (!S_ISREG(sb.st_mode))
 318                 isreg = 0;
 319
 320         /*
 321          * Try to read the first few uncompressed bytes from the input file
 322          * before blindly truncating the output file.
 323          */
 324         if ((nr = fread(buf, 1, sizeof(buf), ifp)) == 0) {
 325                 cwarn("%s", in);
 326                 (void)fclose(ifp);
 327                 return;
 328         }
 329         if ((ofp = fopen(out, "w")) == NULL ||
 330             (nr != 0 && fwrite(buf, 1, nr, ofp) != nr)) {
 331                 cwarn("%s", out);
 332                 (void)fclose(ifp);
 333                 return;
 334         }
 335
 336         while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0)
 337                 if (fwrite(buf, 1, nr, ofp) != nr) {
 338                         cwarn("%s", out);
 339                         goto err;
 340                 }
 341
 342         if (ferror(ifp) || fclose(ifp)) {
 343                 cwarn("%s", in);
 344                 goto err;
 345         }
 346         ifp = NULL;
 347
 348         if (fclose(ofp)) {
 349                 cwarn("%s", out);
 350                 goto err;
 351         }
 352
 353         if (!cat && isreg) {
 354                 setfile(out, &sb);
 355
 356                 if (unlink(in))
 357                         cwarn("%s", in);
 358                 if (verbose) {
 359                         struct stat isb = sb;
 360                         stat(out, &sb);
 361                         (void)fprintf(stderr, "%s: ", out);
 362                         if (isb.st_size > sb.st_size)
 363                                 (void)fprintf(stderr, "%.0f%% compression\n",
 364                                     ((float)sb.st_size / isb.st_size) * 100.0);
 365                         else
 366                                 (void)fprintf(stderr, "%.0f%% expansion\n",
 367                                     ((float)isb.st_size / sb.st_size) * 100.0);
 368                 }
 369         }
 370         return;
 371
 372 err:    if (ofp) {
 373                 if (!cat && oreg)
 374                         (void)unlink(out);
 375                 (void)fclose(ofp);
 376         }
 377         if (ifp)
 378                 (void)fclose(ifp);
 379 }
 380
 381 void
 382 setfile(const char *name, struct stat *fs)
 383 {
 384         static struct timeval tv[2];
 385
 386         fs->st_mode &= S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO;
 387
 388         TIMESPEC_TO_TIMEVAL(&tv[0], &fs->st_atimespec);
 389         TIMESPEC_TO_TIMEVAL(&tv[1], &fs->st_mtimespec);
 390         if (utimes(name, tv))
 391                 cwarn("utimes: %s", name);
 392
 393         /*
 394          * Changing the ownership probably won't succeed, unless we're root
 395          * or POSIX_CHOWN_RESTRICTED is not set.  Set uid/gid before setting
 396          * the mode; current BSD behavior is to remove all setuid bits on
 397          * chown.  If chown fails, lose setuid/setgid bits.
 398          */
 399         if (chown(name, fs->st_uid, fs->st_gid)) {
 400                 if (errno != EPERM)
 401                         cwarn("chown: %s", name);
 402                 fs->st_mode &= ~(S_ISUID|S_ISGID);
 403         }
 404         if (chmod(name, fs->st_mode) && errno != ENOTSUP)
 405                 cwarn("chmod: %s", name);
 406
 407         if (chflags(name, fs->st_flags) && errno != ENOTSUP)
 408                 cwarn("chflags: %s", name);
 409 }
 410
 411 int
 412 permission(const char *fname)
 413 {
 414         int ch, first;
 415
 416         if (!isatty(fileno(stderr)))
 417                 return (0);
 418         (void)fprintf(stderr, "overwrite %s? ", fname);
 419         first = ch = getchar();
 420         while (ch != '\n' && ch != EOF)
 421                 ch = getchar();
 422         return (first == 'y');
 423 }
 424
 425 void
 426 usage(int iscompress)
 427 {
 428         if (iscompress)
 429                 (void)fprintf(stderr,
 430                     "usage: compress [-cfv] [-b bits] [file ...]\n");
 431         else
 432                 (void)fprintf(stderr,
 433                     "usage: uncompress [-cfv] [file ...]\n");
 434         exit(1);
 435 }
 436
 437 void
 438 cwarnx(const char *fmt, ...)
 439 {
 440         va_list ap;
 441
 442         va_start(ap, fmt);
 443         vwarnx(fmt, ap);
 444         va_end(ap);
 445         eval = 1;
 446 }
 447
 448 void
 449 cwarn(const char *fmt, ...)
 450 {
 451         va_list ap;
 452
 453         va_start(ap, fmt);
 454         vwarn(fmt, ap);
 455         va_end(ap);
 456         eval = 1;
 457 }