file_cmds/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 #include <sys/attr.h>
  50
  51 #include <err.h>
  52 #include <errno.h>
  53 #include <stdarg.h>
  54 #include <stdio.h>
  55 #include <stdlib.h>
  56 #include <string.h>
  57 #include <unistd.h>
  58 #include <locale.h>
  59
  60 #include "zopen.h"
  61
  62 void    compress(const char *, const char *, int);
  63 void    cwarn(const char *, ...) __printflike(1, 2);
  64 void    cwarnx(const char *, ...) __printflike(1, 2);
  65 void    decompress(const char *, const char *, int);
  66 int     permission(const char *);
  67 void    setfile(const char *, struct stat *);
  68 void    usage(int);
  69
  70 int eval, force, verbose, cat;
  71
  72 int
  73 main(int argc, char *argv[])
  74 {
  75         enum {COMPRESS, DECOMPRESS} style;
  76         size_t len;
  77         int bits, ch;
  78         char *p, newname[MAXPATHLEN];
  79
  80         if (argc < 1)
  81                 usage(1);
  82         cat = 0;
  83         if ((p = rindex(argv[0], '/')) == NULL)
  84                 p = argv[0];
  85         else
  86                 ++p;
  87         if (!strcmp(p, "uncompress"))
  88                 style = DECOMPRESS;
  89         else if (!strcmp(p, "compress"))
  90                 style = COMPRESS;
  91         else if (!strcmp(p, "zcat")) {
  92                 cat = 1;
  93                 style = DECOMPRESS;
  94         } else
  95                 errx(1, "unknown program name");
  96
  97         bits = 0;
  98         while ((ch = getopt(argc, argv, "b:cdfv")) != -1)
  99                 switch(ch) {
 100                 case 'b':
 101                         bits = strtol(optarg, &p, 10);
 102                         if (*p)
 103                                 errx(1, "illegal bit count -- %s", optarg);
 104                         break;
 105                 case 'c':
 106                         cat = 1;
 107                         break;
 108                 case 'd':               /* Backward compatible. */
 109                         style = DECOMPRESS;
 110                         break;
 111                 case 'f':
 112                         force = 1;
 113                         break;
 114                 case 'v':
 115                         verbose = 1;
 116                         break;
 117                 case '?':
 118                 default:
 119                         usage(style == COMPRESS);
 120                 }
 121         argc -= optind;
 122         argv += optind;
 123
 124         if (argc == 0) {
 125                 cat = 1;
 126                 switch(style) {
 127                 case COMPRESS:
 128                         (void)compress("/dev/stdin", "/dev/stdout", bits);
 129                         break;
 130                 case DECOMPRESS:
 131                         (void)decompress("/dev/stdin", "/dev/stdout", bits);
 132                         break;
 133                 }
 134                 exit (eval);
 135         }
 136
 137     /*
 138      * The UNIX standard requires that `uncompress -c` be able to have multiple file parameters given.
 139      */
 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 = NULL, *ofp = NULL;
 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         if ((ifp = fopen(in, "r")) == NULL) {
 220                 cwarn("%s", in);
 221                 return;
 222         }
 223         if (stat(in, &isb)) {           /* DON'T FSTAT! */
 224                 cwarn("%s", in);
 225                 goto err;
 226         }
 227         if (!S_ISREG(isb.st_mode))
 228                 isreg = 0;
 229
 230         if ((ofp = zopen(out, "w", bits)) == NULL) {
 231                 cwarn("%s", out);
 232                 goto err;
 233         }
 234         while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0)
 235                 if (fwrite(buf, 1, nr, ofp) != nr) {
 236                         cwarn("%s", out);
 237                         goto err;
 238                 }
 239
 240         if (ferror(ifp) || fclose(ifp)) {
 241                 cwarn("%s", in);
 242                 goto err;
 243         }
 244         ifp = NULL;
 245
 246         if (fclose(ofp)) {
 247                 cwarn("%s", out);
 248                 goto err;
 249         }
 250         ofp = NULL;
 251
 252         if (!cat && isreg) {
 253                 if (stat(out, &sb)) {
 254                         cwarn("%s", out);
 255                         goto err;
 256                 }
 257
 258                 if (!force && sb.st_size >= isb.st_size) {
 259                         if (verbose)
 260                 (void)fprintf(stderr, "%s: file would grow; left unmodified\n",
 261                     in);
 262                         eval = 2;
 263                         if (unlink(out))
 264                                 cwarn("%s", out);
 265                         goto err;
 266                 }
 267
 268                 setfile(out, &isb);
 269
 270                 if (unlink(in))
 271                         cwarn("%s", in);
 272
 273                 if (verbose) {
 274                         (void)fprintf(stderr, "%s: ", out);
 275                         if (isb.st_size > sb.st_size)
 276                                 (void)fprintf(stderr, "%.0f%% compression\n",
 277                                     ((float)sb.st_size / isb.st_size) * 100.0);
 278                         else
 279                                 (void)fprintf(stderr, "%.0f%% expansion\n",
 280                                     ((float)isb.st_size / sb.st_size) * 100.0);
 281                 }
 282         }
 283         return;
 284
 285 err:    if (ofp) {
 286                 if (!cat && oreg)
 287                         (void)unlink(out);
 288                 (void)fclose(ofp);
 289         }
 290         if (ifp)
 291                 (void)fclose(ifp);
 292 }
 293
 294 void
 295 decompress(const char *in, const char *out, int bits)
 296 {
 297         size_t nr;
 298         struct stat sb;
 299         FILE *ifp, *ofp;
 300         int exists, isreg, oreg;
 301         u_char buf[1024];
 302
 303         exists = !stat(out, &sb);
 304         if (!force && exists && S_ISREG(sb.st_mode) && !cat && !permission(out)) {
 305                 cwarnx("%s already exists", out);
 306                 return;
 307         }
 308         isreg = oreg = !exists || S_ISREG(sb.st_mode);
 309
 310         ofp = NULL;
 311         if ((ifp = zopen(in, "r", bits)) == NULL) {
 312                 cwarn("%s", in);
 313                 return;
 314         }
 315         if (stat(in, &sb)) {
 316                 cwarn("%s", in);
 317                 goto err;
 318         }
 319         if (!S_ISREG(sb.st_mode))
 320                 isreg = 0;
 321
 322         /*
 323          * Try to read the first few uncompressed bytes from the input file
 324          * before blindly truncating the output file.
 325          */
 326         if ((nr = fread(buf, 1, sizeof(buf), ifp)) == 0) {
 327                 cwarn("%s", in);
 328                 (void)fclose(ifp);
 329                 return;
 330         }
 331         if ((ofp = fopen(out, "w")) == NULL ||
 332             (nr != 0 && fwrite(buf, 1, nr, ofp) != nr)) {
 333                 cwarn("%s", out);
 334                 (void)fclose(ifp);
 335                 return;
 336         }
 337
 338         while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0)
 339                 if (fwrite(buf, 1, nr, ofp) != nr) {
 340                         cwarn("%s", out);
 341                         goto err;
 342                 }
 343
 344         if (ferror(ifp) || fclose(ifp)) {
 345                 cwarn("%s", in);
 346                 goto err;
 347         }
 348         ifp = NULL;
 349
 350         if (fclose(ofp)) {
 351                 cwarn("%s", out);
 352                 goto err;
 353         }
 354
 355         if (!cat && isreg) {
 356                 setfile(out, &sb);
 357
 358                 if (unlink(in))
 359                         cwarn("%s", in);
 360                 if (verbose) {
 361                         struct stat isb = sb;
 362                         stat(out, &sb);
 363                         (void)fprintf(stderr, "%s: ", out);
 364                         if (isb.st_size > sb.st_size)
 365                                 (void)fprintf(stderr, "%.0f%% compression\n",
 366                                     ((float)sb.st_size / isb.st_size) * 100.0);
 367                         else
 368                                 (void)fprintf(stderr, "%.0f%% expansion\n",
 369                                     ((float)isb.st_size / sb.st_size) * 100.0);
 370                 }
 371         }
 372         return;
 373
 374 err:    if (ofp) {
 375                 if (!cat && oreg)
 376                         (void)unlink(out);
 377                 (void)fclose(ofp);
 378         }
 379         if (ifp)
 380                 (void)fclose(ifp);
 381 }
 382
 383 void
 384 setfile(const char *name, struct stat *fs)
 385 {
 386         struct attrlist ts_req = {};
 387         struct {
 388                 struct timespec mtime;
 389                 struct timespec atime;
 390         } set_ts;
 391
 392         fs->st_mode &= S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO;
 393
 394         ts_req.bitmapcount = ATTR_BIT_MAP_COUNT;
 395         ts_req.commonattr = ATTR_CMN_MODTIME | ATTR_CMN_ACCTIME;
 396         set_ts.mtime = fs->st_mtimespec;
 397         set_ts.atime = fs->st_atimespec;
 398
 399         if (setattrlist(name, &ts_req, &set_ts, sizeof(set_ts), 0))
 400                 cwarn("setattrlist: %s", name);
 401
 402         /*
 403          * Changing the ownership probably won't succeed, unless we're root
 404          * or POSIX_CHOWN_RESTRICTED is not set.  Set uid/gid before setting
 405          * the mode; current BSD behavior is to remove all setuid bits on
 406          * chown.  If chown fails, lose setuid/setgid bits.
 407          */
 408         if (chown(name, fs->st_uid, fs->st_gid)) {
 409                 if (errno != EPERM)
 410                         cwarn("chown: %s", name);
 411                 fs->st_mode &= ~(S_ISUID|S_ISGID);
 412         }
 413         if (chmod(name, fs->st_mode) && errno != ENOTSUP)
 414                 cwarn("chmod: %s", name);
 415
 416         if (chflags(name, fs->st_flags) && errno != ENOTSUP)
 417                 cwarn("chflags: %s", name);
 418 }
 419
 420 int
 421 permission(const char *fname)
 422 {
 423         int ch, first;
 424         char resp[] = {'\0', '\0'};
 425
 426         if (!isatty(fileno(stderr)))
 427                 return (0);
 428         (void)fprintf(stderr, "overwrite %s? ", fname);
 429
 430         /* Load user specified locale */
 431         setlocale(LC_MESSAGES, "");
 432
 433         first = ch = getchar();
 434         while (ch != '\n' && ch != EOF)
 435                 ch = getchar();
 436
 437         /* only care about first character */
 438         resp[0] = first;
 439
 440         return (rpmatch(resp) == 1);
 441 }
 442
 443 void
 444 usage(int iscompress)
 445 {
 446         if (iscompress)
 447                 (void)fprintf(stderr,
 448                     "usage: compress [-cfv] [-b bits] [file ...]\n");
 449         else
 450                 (void)fprintf(stderr,
 451                     "usage: uncompress [-cfv] [file ...]\n");
 452         exit(1);
 453 }
 454
 455 void
 456 cwarnx(const char *fmt, ...)
 457 {
 458         va_list ap;
 459
 460         va_start(ap, fmt);
 461         vwarnx(fmt, ap);
 462         va_end(ap);
 463         eval = 1;
 464 }
 465
 466 void
 467 cwarn(const char *fmt, ...)
 468 {
 469         va_list ap;
 470
 471         va_start(ap, fmt);
 472         vwarn(fmt, ap);
 473         va_end(ap);
 474         eval = 1;
 475 }