usr.bin/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  * @(#) Copyright (c) 1992, 1993 The Regents of the University of California.  All rights reserved.
  34  * @(#)compress.c       8.2 (Berkeley) 1/7/94
  35  * $FreeBSD: src/usr.bin/compress/compress.c,v 1.7.6.5 2002/07/16 00:56:04 tjr Exp $
  36  * $DragonFly: src/usr.bin/compress/compress.c,v 1.4 2004/08/30 18:06:49 eirikn Exp $
  37  */
  38
  39 #include <sys/param.h>
  40 #include <sys/stat.h>
  41 #include <sys/time.h>
  42
  43 #include <err.h>
  44 #include <errno.h>
  45 #include <stdarg.h>
  46 #include <stdio.h>
  47 #include <stdlib.h>
  48 #include <string.h>
  49 #include <unistd.h>
  50
  51 #include "zopen.h"
  52
  53 void    compress(const char *, const char *, int);
  54 void    cwarn(const char *, ...) __printflike(1, 2);
  55 void    cwarnx(const char *, ...) __printflike(1, 2);
  56 void    decompress(const char *, const char *, int);
  57 int     permission(const char *);
  58 void    setfile(const char *, struct stat *);
  59 void    usage(int);
  60
  61 int eval, force, verbose;
  62
  63 int
  64 main(int argc, char **argv)
  65 {
  66         enum {COMPRESS, DECOMPRESS} style;
  67         size_t len;
  68         int bits, cat, ch;
  69         char *p, newname[MAXPATHLEN];
  70
  71         cat = 0;
  72         if ((p = strrchr(argv[0], '/')) == NULL)
  73                 p = argv[0];
  74         else
  75                 ++p;
  76         if (!strcmp(p, "uncompress"))
  77                 style = DECOMPRESS;
  78         else if (!strcmp(p, "compress"))
  79                 style = COMPRESS;
  80         else if (!strcmp(p, "zcat")) {
  81                 cat = 1;
  82                 style = DECOMPRESS;
  83         } else
  84                 errx(1, "unknown program name");
  85
  86         bits = 0;
  87         while ((ch = getopt(argc, argv, "b:cdfv")) != -1)
  88                 switch(ch) {
  89                 case 'b':
  90                         bits = strtol(optarg, &p, 10);
  91                         if (*p)
  92                                 errx(1, "illegal bit count -- %s", optarg);
  93                         break;
  94                 case 'c':
  95                         cat = 1;
  96                         break;
  97                 case 'd':               /* Backward compatible. */
  98                         style = DECOMPRESS;
  99                         break;
 100                 case 'f':
 101                         force = 1;
 102                         break;
 103                 case 'v':
 104                         verbose = 1;
 105                         break;
 106                 case '?':
 107                 default:
 108                         usage(style == COMPRESS);
 109                 }
 110         argc -= optind;
 111         argv += optind;
 112
 113         if (argc == 0) {
 114                 switch(style) {
 115                 case COMPRESS:
 116                         (void)compress("/dev/stdin", "/dev/stdout", bits);
 117                         break;
 118                 case DECOMPRESS:
 119                         (void)decompress("/dev/stdin", "/dev/stdout", bits);
 120                         break;
 121                 }
 122                 exit (eval);
 123         }
 124
 125         if (cat == 1 && argc > 1)
 126                 errx(1, "the -c option permits only a single file argument");
 127
 128         for (; *argv; ++argv)
 129                 switch(style) {
 130                 case COMPRESS:
 131                         if (strcmp(*argv, "-") == 0) {
 132                                 compress("/dev/stdin", "/dev/stdout", bits);
 133                                 break;
 134                         } else if (cat) {
 135                                 compress(*argv, "/dev/stdout", bits);
 136                                 break;
 137                         }
 138                         if ((p = strrchr(*argv, '.')) != NULL &&
 139                             !strcmp(p, ".Z")) {
 140                                 cwarnx("%s: name already has trailing .Z",
 141                                     *argv);
 142                                 break;
 143                         }
 144                         len = strlen(*argv);
 145                         if (len > sizeof(newname) - 3) {
 146                                 cwarnx("%s: name too long", *argv);
 147                                 break;
 148                         }
 149                         memmove(newname, *argv, len);
 150                         newname[len] = '.';
 151                         newname[len + 1] = 'Z';
 152                         newname[len + 2] = '\0';
 153                         compress(*argv, newname, bits);
 154                         break;
 155                 case DECOMPRESS:
 156                         if (strcmp(*argv, "-") == 0) {
 157                                 decompress("/dev/stdin", "/dev/stdout", bits);
 158                                 break;
 159                         }
 160                         len = strlen(*argv);
 161                         if ((p = strrchr(*argv, '.')) == NULL ||
 162                             strcmp(p, ".Z")) {
 163                                 if (len > sizeof(newname) - 3) {
 164                                         cwarnx("%s: name too long", *argv);
 165                                         break;
 166                                 }
 167                                 memmove(newname, *argv, len);
 168                                 newname[len] = '.';
 169                                 newname[len + 1] = 'Z';
 170                                 newname[len + 2] = '\0';
 171                                 decompress(newname,
 172                                     cat ? "/dev/stdout" : *argv, bits);
 173                         } else {
 174                                 if (len - 2 > sizeof(newname) - 1) {
 175                                         cwarnx("%s: name too long", *argv);
 176                                         break;
 177                                 }
 178                                 memmove(newname, *argv, len - 2);
 179                                 newname[len - 2] = '\0';
 180                                 decompress(*argv,
 181                                     cat ? "/dev/stdout" : newname, bits);
 182                         }
 183                         break;
 184                 }
 185         exit (eval);
 186 }
 187
 188 void
 189 compress(const char *in, const char *out, int bits)
 190 {
 191         size_t nr;
 192         struct stat isb, sb;
 193         FILE *ifp, *ofp;
 194         int exists, isreg, oreg;
 195         u_char buf[1024];
 196
 197         exists = !stat(out, &sb);
 198         if (!force && exists && S_ISREG(sb.st_mode) && !permission(out))
 199                 return;
 200         isreg = oreg = !exists || S_ISREG(sb.st_mode);
 201
 202         ifp = ofp = NULL;
 203         if ((ifp = fopen(in, "r")) == NULL) {
 204                 cwarn("%s", in);
 205                 return;
 206         }
 207         if (stat(in, &isb)) {           /* DON'T FSTAT! */
 208                 cwarn("%s", in);
 209                 goto err;
 210         }
 211         if (!S_ISREG(isb.st_mode))
 212                 isreg = 0;
 213
 214         if ((ofp = zopen(out, "w", bits)) == NULL) {
 215                 cwarn("%s", out);
 216                 goto err;
 217         }
 218         while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0)
 219                 if (fwrite(buf, 1, nr, ofp) != nr) {
 220                         cwarn("%s", out);
 221                         goto err;
 222                 }
 223
 224         if (ferror(ifp) || fclose(ifp)) {
 225                 cwarn("%s", in);
 226                 goto err;
 227         }
 228         ifp = NULL;
 229
 230         if (fclose(ofp)) {
 231                 cwarn("%s", out);
 232                 goto err;
 233         }
 234         ofp = NULL;
 235
 236         if (isreg) {
 237                 if (stat(out, &sb)) {
 238                         cwarn("%s", out);
 239                         goto err;
 240                 }
 241
 242                 if (!force && sb.st_size >= isb.st_size) {
 243                         if (verbose)
 244                 (void)fprintf(stderr, "%s: file would grow; left unmodified\n",
 245                     in);
 246                         eval = 2;
 247                         if (unlink(out))
 248                                 cwarn("%s", out);
 249                         goto err;
 250                 }
 251
 252                 setfile(out, &isb);
 253
 254                 if (unlink(in))
 255                         cwarn("%s", in);
 256
 257                 if (verbose) {
 258                         (void)fprintf(stderr, "%s: ", out);
 259                         if (isb.st_size > sb.st_size)
 260                                 (void)fprintf(stderr, "%.0f%% compression\n",
 261                                     ((float)sb.st_size / isb.st_size) * 100.0);
 262                         else
 263                                 (void)fprintf(stderr, "%.0f%% expansion\n",
 264                                     ((float)isb.st_size / sb.st_size) * 100.0);
 265                 }
 266         }
 267         return;
 268
 269 err:    if (ofp) {
 270                 if (oreg)
 271                         (void)unlink(out);
 272                 (void)fclose(ofp);
 273         }
 274         if (ifp)
 275                 (void)fclose(ifp);
 276 }
 277
 278 void
 279 decompress(const char *in, const char *out, int bits)
 280 {
 281         size_t nr;
 282         struct stat sb;
 283         FILE *ifp, *ofp;
 284         int exists, isreg, oreg;
 285         u_char buf[1024];
 286
 287         exists = !stat(out, &sb);
 288         if (!force && exists && S_ISREG(sb.st_mode) && !permission(out))
 289                 return;
 290         isreg = oreg = !exists || S_ISREG(sb.st_mode);
 291
 292         ifp = ofp = NULL;
 293         if ((ofp = fopen(out, "w")) == NULL) {
 294                 cwarn("%s", out);
 295                 return;
 296         }
 297
 298         if ((ifp = zopen(in, "r", bits)) == NULL) {
 299                 cwarn("%s", in);
 300                 goto err;
 301         }
 302         if (stat(in, &sb)) {
 303                 cwarn("%s", in);
 304                 goto err;
 305         }
 306         if (!S_ISREG(sb.st_mode))
 307                 isreg = 0;
 308
 309         while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0)
 310                 if (fwrite(buf, 1, nr, ofp) != nr) {
 311                         cwarn("%s", out);
 312                         goto err;
 313                 }
 314
 315         if (ferror(ifp) || fclose(ifp)) {
 316                 cwarn("%s", in);
 317                 goto err;
 318         }
 319         ifp = NULL;
 320
 321         if (fclose(ofp)) {
 322                 cwarn("%s", out);
 323                 goto err;
 324         }
 325
 326         if (isreg) {
 327                 setfile(out, &sb);
 328
 329                 if (unlink(in))
 330                         cwarn("%s", in);
 331         }
 332         return;
 333
 334 err:    if (ofp) {
 335                 if (oreg)
 336                         (void)unlink(out);
 337                 (void)fclose(ofp);
 338         }
 339         if (ifp)
 340                 (void)fclose(ifp);
 341 }
 342
 343 void
 344 setfile(const char *name, struct stat *fs)
 345 {
 346         static struct timeval tv[2];
 347
 348         fs->st_mode &= S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO;
 349
 350         TIMESPEC_TO_TIMEVAL(&tv[0], &fs->st_atimespec);
 351         TIMESPEC_TO_TIMEVAL(&tv[1], &fs->st_mtimespec);
 352         if (utimes(name, tv))
 353                 cwarn("utimes: %s", name);
 354
 355         /*
 356          * Changing the ownership probably won't succeed, unless we're root
 357          * or POSIX_CHOWN_RESTRICTED is not set.  Set uid/gid before setting
 358          * the mode; current BSD behavior is to remove all setuid bits on
 359          * chown.  If chown fails, lose setuid/setgid bits.
 360          */
 361         if (chown(name, fs->st_uid, fs->st_gid)) {
 362                 if (errno != EPERM)
 363                         cwarn("chown: %s", name);
 364                 fs->st_mode &= ~(S_ISUID|S_ISGID);
 365         }
 366         if (chmod(name, fs->st_mode) && errno != EOPNOTSUPP)
 367                 cwarn("chmod: %s", name);
 368
 369         if (chflags(name, fs->st_flags) && errno != EOPNOTSUPP)
 370                 cwarn("chflags: %s", name);
 371 }
 372
 373 int
 374 permission(const char *fname)
 375 {
 376         int ch, first;
 377
 378         if (!isatty(fileno(stderr)))
 379                 return (0);
 380         (void)fprintf(stderr, "overwrite %s? ", fname);
 381         first = ch = getchar();
 382         while (ch != '\n' && ch != EOF)
 383                 ch = getchar();
 384         return (first == 'y');
 385 }
 386
 387 void
 388 usage(int iscompress)
 389 {
 390         if (iscompress)
 391                 (void)fprintf(stderr,
 392                     "usage: compress [-cfv] [-b bits] [file ...]\n");
 393         else
 394                 (void)fprintf(stderr,
 395                     "usage: uncompress [-c] [-b bits] [file ...]\n");
 396         exit(1);
 397 }
 398
 399 void
 400 cwarnx(const char *fmt, ...)
 401 {
 402         va_list ap;
 403
 404         va_start(ap, fmt);
 405         vwarnx(fmt, ap);
 406         va_end(ap);
 407         eval = 1;
 408 }
 409
 410 void
 411 cwarn(const char *fmt, ...)
 412 {
 413         va_list ap;
 414
 415         va_start(ap, fmt);
 416         vwarn(fmt, ap);
 417         va_end(ap);
 418         eval = 1;
 419 }