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. 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  * @(#) Copyright (c) 1992, 1993 The Regents of the University of California.  All rights reserved.
  30  * @(#)compress.c       8.2 (Berkeley) 1/7/94
  31  * $FreeBSD: src/usr.bin/compress/compress.c,v 1.7.6.5 2002/07/16 00:56:04 tjr Exp $
  32  * $DragonFly: src/usr.bin/compress/compress.c,v 1.4 2004/08/30 18:06:49 eirikn Exp $
  33  */
  34
  35 #include <sys/param.h>
  36 #include <sys/stat.h>
  37 #include <sys/time.h>
  38
  39 #include <err.h>
  40 #include <errno.h>
  41 #include <stdarg.h>
  42 #include <stdio.h>
  43 #include <stdlib.h>
  44 #include <string.h>
  45 #include <unistd.h>
  46
  47 #include "zopen.h"
  48
  49 void    compress(const char *, const char *, int);
  50 void    cwarn(const char *, ...) __printflike(1, 2);
  51 void    cwarnx(const char *, ...) __printflike(1, 2);
  52 void    decompress(const char *, const char *, int);
  53 int     permission(const char *);
  54 void    setfile(const char *, struct stat *);
  55 void    usage(int);
  56
  57 int eval, force, verbose;
  58
  59 int
  60 main(int argc, char **argv)
  61 {
  62         enum {COMPRESS, DECOMPRESS} style;
  63         size_t len;
  64         int bits, cat, ch;
  65         char *p, newname[MAXPATHLEN];
  66
  67         cat = 0;
  68         if ((p = strrchr(argv[0], '/')) == NULL)
  69                 p = argv[0];
  70         else
  71                 ++p;
  72         if (!strcmp(p, "uncompress"))
  73                 style = DECOMPRESS;
  74         else if (!strcmp(p, "compress"))
  75                 style = COMPRESS;
  76         else if (!strcmp(p, "zcat")) {
  77                 cat = 1;
  78                 style = DECOMPRESS;
  79         } else
  80                 errx(1, "unknown program name");
  81
  82         bits = 0;
  83         while ((ch = getopt(argc, argv, "b:cdfv")) != -1)
  84                 switch(ch) {
  85                 case 'b':
  86                         bits = strtol(optarg, &p, 10);
  87                         if (*p)
  88                                 errx(1, "illegal bit count -- %s", optarg);
  89                         break;
  90                 case 'c':
  91                         cat = 1;
  92                         break;
  93                 case 'd':               /* Backward compatible. */
  94                         style = DECOMPRESS;
  95                         break;
  96                 case 'f':
  97                         force = 1;
  98                         break;
  99                 case 'v':
 100                         verbose = 1;
 101                         break;
 102                 case '?':
 103                 default:
 104                         usage(style == COMPRESS);
 105                 }
 106         argc -= optind;
 107         argv += optind;
 108
 109         if (argc == 0) {
 110                 switch(style) {
 111                 case COMPRESS:
 112                         (void)compress("/dev/stdin", "/dev/stdout", bits);
 113                         break;
 114                 case DECOMPRESS:
 115                         (void)decompress("/dev/stdin", "/dev/stdout", bits);
 116                         break;
 117                 }
 118                 exit (eval);
 119         }
 120
 121         if (cat == 1 && argc > 1)
 122                 errx(1, "the -c option permits only a single file argument");
 123
 124         for (; *argv; ++argv)
 125                 switch(style) {
 126                 case COMPRESS:
 127                         if (strcmp(*argv, "-") == 0) {
 128                                 compress("/dev/stdin", "/dev/stdout", bits);
 129                                 break;
 130                         } else if (cat) {
 131                                 compress(*argv, "/dev/stdout", bits);
 132                                 break;
 133                         }
 134                         if ((p = strrchr(*argv, '.')) != NULL &&
 135                             !strcmp(p, ".Z")) {
 136                                 cwarnx("%s: name already has trailing .Z",
 137                                     *argv);
 138                                 break;
 139                         }
 140                         len = strlen(*argv);
 141                         if (len > sizeof(newname) - 3) {
 142                                 cwarnx("%s: name too long", *argv);
 143                                 break;
 144                         }
 145                         memmove(newname, *argv, len);
 146                         newname[len] = '.';
 147                         newname[len + 1] = 'Z';
 148                         newname[len + 2] = '\0';
 149                         compress(*argv, newname, bits);
 150                         break;
 151                 case DECOMPRESS:
 152                         if (strcmp(*argv, "-") == 0) {
 153                                 decompress("/dev/stdin", "/dev/stdout", bits);
 154                                 break;
 155                         }
 156                         len = strlen(*argv);
 157                         if ((p = strrchr(*argv, '.')) == NULL ||
 158                             strcmp(p, ".Z")) {
 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                                 decompress(newname,
 168                                     cat ? "/dev/stdout" : *argv, bits);
 169                         } else {
 170                                 if (len - 2 > sizeof(newname) - 1) {
 171                                         cwarnx("%s: name too long", *argv);
 172                                         break;
 173                                 }
 174                                 memmove(newname, *argv, len - 2);
 175                                 newname[len - 2] = '\0';
 176                                 decompress(*argv,
 177                                     cat ? "/dev/stdout" : newname, bits);
 178                         }
 179                         break;
 180                 }
 181         exit (eval);
 182 }
 183
 184 void
 185 compress(const char *in, const char *out, int bits)
 186 {
 187         size_t nr;
 188         struct stat isb, sb;
 189         FILE *ifp, *ofp;
 190         int exists, isreg, oreg;
 191         u_char buf[1024];
 192
 193         exists = !stat(out, &sb);
 194         if (!force && exists && S_ISREG(sb.st_mode) && !permission(out))
 195                 return;
 196         isreg = oreg = !exists || S_ISREG(sb.st_mode);
 197
 198         ifp = ofp = NULL;
 199         if ((ifp = fopen(in, "r")) == NULL) {
 200                 cwarn("%s", in);
 201                 return;
 202         }
 203         if (stat(in, &isb)) {           /* DON'T FSTAT! */
 204                 cwarn("%s", in);
 205                 goto err;
 206         }
 207         if (!S_ISREG(isb.st_mode))
 208                 isreg = 0;
 209
 210         if ((ofp = zopen(out, "w", bits)) == NULL) {
 211                 cwarn("%s", out);
 212                 goto err;
 213         }
 214         while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0)
 215                 if (fwrite(buf, 1, nr, ofp) != nr) {
 216                         cwarn("%s", out);
 217                         goto err;
 218                 }
 219
 220         if (ferror(ifp) || fclose(ifp)) {
 221                 cwarn("%s", in);
 222                 goto err;
 223         }
 224         ifp = NULL;
 225
 226         if (fclose(ofp)) {
 227                 cwarn("%s", out);
 228                 goto err;
 229         }
 230         ofp = NULL;
 231
 232         if (isreg) {
 233                 if (stat(out, &sb)) {
 234                         cwarn("%s", out);
 235                         goto err;
 236                 }
 237
 238                 if (!force && sb.st_size >= isb.st_size) {
 239                         if (verbose)
 240                 (void)fprintf(stderr, "%s: file would grow; left unmodified\n",
 241                     in);
 242                         eval = 2;
 243                         if (unlink(out))
 244                                 cwarn("%s", out);
 245                         goto err;
 246                 }
 247
 248                 setfile(out, &isb);
 249
 250                 if (unlink(in))
 251                         cwarn("%s", in);
 252
 253                 if (verbose) {
 254                         (void)fprintf(stderr, "%s: ", out);
 255                         if (isb.st_size > sb.st_size)
 256                                 (void)fprintf(stderr, "%.0f%% compression\n",
 257                                     ((float)sb.st_size / isb.st_size) * 100.0);
 258                         else
 259                                 (void)fprintf(stderr, "%.0f%% expansion\n",
 260                                     ((float)isb.st_size / sb.st_size) * 100.0);
 261                 }
 262         }
 263         return;
 264
 265 err:    if (ofp) {
 266                 if (oreg)
 267                         (void)unlink(out);
 268                 (void)fclose(ofp);
 269         }
 270         if (ifp)
 271                 (void)fclose(ifp);
 272 }
 273
 274 void
 275 decompress(const char *in, const char *out, int bits)
 276 {
 277         size_t nr;
 278         struct stat sb;
 279         FILE *ifp, *ofp;
 280         int exists, isreg, oreg;
 281         u_char buf[1024];
 282
 283         exists = !stat(out, &sb);
 284         if (!force && exists && S_ISREG(sb.st_mode) && !permission(out))
 285                 return;
 286         isreg = oreg = !exists || S_ISREG(sb.st_mode);
 287
 288         ifp = ofp = NULL;
 289         if ((ofp = fopen(out, "w")) == NULL) {
 290                 cwarn("%s", out);
 291                 return;
 292         }
 293
 294         if ((ifp = zopen(in, "r", bits)) == NULL) {
 295                 cwarn("%s", in);
 296                 goto err;
 297         }
 298         if (stat(in, &sb)) {
 299                 cwarn("%s", in);
 300                 goto err;
 301         }
 302         if (!S_ISREG(sb.st_mode))
 303                 isreg = 0;
 304
 305         while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0)
 306                 if (fwrite(buf, 1, nr, ofp) != nr) {
 307                         cwarn("%s", out);
 308                         goto err;
 309                 }
 310
 311         if (ferror(ifp) || fclose(ifp)) {
 312                 cwarn("%s", in);
 313                 goto err;
 314         }
 315         ifp = NULL;
 316
 317         if (fclose(ofp)) {
 318                 cwarn("%s", out);
 319                 goto err;
 320         }
 321
 322         if (isreg) {
 323                 setfile(out, &sb);
 324
 325                 if (unlink(in))
 326                         cwarn("%s", in);
 327         }
 328         return;
 329
 330 err:    if (ofp) {
 331                 if (oreg)
 332                         (void)unlink(out);
 333                 (void)fclose(ofp);
 334         }
 335         if (ifp)
 336                 (void)fclose(ifp);
 337 }
 338
 339 void
 340 setfile(const char *name, struct stat *fs)
 341 {
 342         static struct timeval tv[2];
 343
 344         fs->st_mode &= S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO;
 345
 346         TIMESPEC_TO_TIMEVAL(&tv[0], &fs->st_atimespec);
 347         TIMESPEC_TO_TIMEVAL(&tv[1], &fs->st_mtimespec);
 348         if (utimes(name, tv))
 349                 cwarn("utimes: %s", name);
 350
 351         /*
 352          * Changing the ownership probably won't succeed, unless we're root
 353          * or POSIX_CHOWN_RESTRICTED is not set.  Set uid/gid before setting
 354          * the mode; current BSD behavior is to remove all setuid bits on
 355          * chown.  If chown fails, lose setuid/setgid bits.
 356          */
 357         if (chown(name, fs->st_uid, fs->st_gid)) {
 358                 if (errno != EPERM)
 359                         cwarn("chown: %s", name);
 360                 fs->st_mode &= ~(S_ISUID|S_ISGID);
 361         }
 362         if (chmod(name, fs->st_mode) && errno != EOPNOTSUPP)
 363                 cwarn("chmod: %s", name);
 364
 365         if (chflags(name, fs->st_flags) && errno != EOPNOTSUPP)
 366                 cwarn("chflags: %s", name);
 367 }
 368
 369 int
 370 permission(const char *fname)
 371 {
 372         int ch, first;
 373
 374         if (!isatty(fileno(stderr)))
 375                 return (0);
 376         (void)fprintf(stderr, "overwrite %s? ", fname);
 377         first = ch = getchar();
 378         while (ch != '\n' && ch != EOF)
 379                 ch = getchar();
 380         return (first == 'y');
 381 }
 382
 383 void
 384 usage(int iscompress)
 385 {
 386         if (iscompress)
 387                 (void)fprintf(stderr,
 388                     "usage: compress [-cfv] [-b bits] [file ...]\n");
 389         else
 390                 (void)fprintf(stderr,
 391                     "usage: uncompress [-c] [-b bits] [file ...]\n");
 392         exit(1);
 393 }
 394
 395 void
 396 cwarnx(const char *fmt, ...)
 397 {
 398         va_list ap;
 399
 400         va_start(ap, fmt);
 401         vwarnx(fmt, ap);
 402         va_end(ap);
 403         eval = 1;
 404 }
 405
 406 void
 407 cwarn(const char *fmt, ...)
 408 {
 409         va_list ap;
 410
 411         va_start(ap, fmt);
 412         vwarn(fmt, ap);
 413         va_end(ap);
 414         eval = 1;
 415 }