bin/cp/cp.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-3-Clause
   3  *
   4  * Copyright (c) 1988, 1993, 1994
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * This code is derived from software contributed to Berkeley by
   8  * David Hitz of Auspex Systems Inc.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. Neither the name of the University nor the names of its contributors
  19  *    may be used to endorse or promote products derived from this software
  20  *    without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  */
  34
  35 #if 0
  36 #ifndef lint
  37 static char const copyright[] =
  38 "@(#) Copyright (c) 1988, 1993, 1994\n\
  39         The Regents of the University of California.  All rights reserved.\n";
  40 #endif /* not lint */
  41
  42 #ifndef lint
  43 static char sccsid[] = "@(#)cp.c        8.2 (Berkeley) 4/1/94";
  44 #endif /* not lint */
  45 #endif
  46 #include <sys/cdefs.h>
  47 __FBSDID("$FreeBSD$");
  48
  49 /*
  50  * Cp copies source files to target files.
  51  *
  52  * The global PATH_T structure "to" always contains the path to the
  53  * current target file.  Since fts(3) does not change directories,
  54  * this path can be either absolute or dot-relative.
  55  *
  56  * The basic algorithm is to initialize "to" and use fts(3) to traverse
  57  * the file hierarchy rooted in the argument list.  A trivial case is the
  58  * case of 'cp file1 file2'.  The more interesting case is the case of
  59  * 'cp file1 file2 ... fileN dir' where the hierarchy is traversed and the
  60  * path (relative to the root of the traversal) is appended to dir (stored
  61  * in "to") to form the final target path.
  62  */
  63
  64 #include <sys/types.h>
  65 #include <sys/stat.h>
  66
  67 #include <err.h>
  68 #include <errno.h>
  69 #include <fts.h>
  70 #include <limits.h>
  71 #include <signal.h>
  72 #include <stdio.h>
  73 #include <stdlib.h>
  74 #include <string.h>
  75 #include <unistd.h>
  76
  77 #include "extern.h"
  78
  79 #define STRIP_TRAILING_SLASH(p) {                                       \
  80         while ((p).p_end > (p).p_path + 1 && (p).p_end[-1] == '/')      \
  81         *--(p).p_end = 0;                                               \
  82 }
  83
  84 static char emptystring[] = "";
  85
  86 PATH_T to = { to.p_path, emptystring, "" };
  87
  88 int fflag, iflag, lflag, nflag, pflag, sflag, vflag;
  89 static int Hflag, Lflag, Rflag, rflag;
  90 volatile sig_atomic_t info;
  91
  92 enum op { FILE_TO_FILE, FILE_TO_DIR, DIR_TO_DNE };
  93
  94 static int copy(char *[], enum op, int);
  95 static void siginfo(int __unused);
  96
  97 int
  98 main(int argc, char *argv[])
  99 {
 100         struct stat to_stat, tmp_stat;
 101         enum op type;
 102         int Pflag, ch, fts_options, r, have_trailing_slash;
 103         char *target;
 104
 105         fts_options = FTS_NOCHDIR | FTS_PHYSICAL;
 106         Pflag = 0;
 107         while ((ch = getopt(argc, argv, "HLPRafilnprsvx")) != -1)
 108                 switch (ch) {
 109                 case 'H':
 110                         Hflag = 1;
 111                         Lflag = Pflag = 0;
 112                         break;
 113                 case 'L':
 114                         Lflag = 1;
 115                         Hflag = Pflag = 0;
 116                         break;
 117                 case 'P':
 118                         Pflag = 1;
 119                         Hflag = Lflag = 0;
 120                         break;
 121                 case 'R':
 122                         Rflag = 1;
 123                         break;
 124                 case 'a':
 125                         pflag = 1;
 126                         Rflag = 1;
 127                         Pflag = 1;
 128                         Hflag = Lflag = 0;
 129                         break;
 130                 case 'f':
 131                         fflag = 1;
 132                         iflag = nflag = 0;
 133                         break;
 134                 case 'i':
 135                         iflag = 1;
 136                         fflag = nflag = 0;
 137                         break;
 138                 case 'l':
 139                         lflag = 1;
 140                         break;
 141                 case 'n':
 142                         nflag = 1;
 143                         fflag = iflag = 0;
 144                         break;
 145                 case 'p':
 146                         pflag = 1;
 147                         break;
 148                 case 'r':
 149                         rflag = Lflag = 1;
 150                         Hflag = Pflag = 0;
 151                         break;
 152                 case 's':
 153                         sflag = 1;
 154                         break;
 155                 case 'v':
 156                         vflag = 1;
 157                         break;
 158                 case 'x':
 159                         fts_options |= FTS_XDEV;
 160                         break;
 161                 default:
 162                         usage();
 163                         break;
 164                 }
 165         argc -= optind;
 166         argv += optind;
 167
 168         if (argc < 2)
 169                 usage();
 170
 171         if (Rflag && rflag)
 172                 errx(1, "the -R and -r options may not be specified together");
 173         if (lflag && sflag)
 174                 errx(1, "the -l and -s options may not be specified together");
 175         if (rflag)
 176                 Rflag = 1;
 177         if (Rflag) {
 178                 if (Hflag)
 179                         fts_options |= FTS_COMFOLLOW;
 180                 if (Lflag) {
 181                         fts_options &= ~FTS_PHYSICAL;
 182                         fts_options |= FTS_LOGICAL;
 183                 }
 184         } else if (!Pflag) {
 185                 fts_options &= ~FTS_PHYSICAL;
 186                 fts_options |= FTS_LOGICAL | FTS_COMFOLLOW;
 187         }
 188         (void)signal(SIGINFO, siginfo);
 189
 190         /* Save the target base in "to". */
 191         target = argv[--argc];
 192         if (strlcpy(to.p_path, target, sizeof(to.p_path)) >= sizeof(to.p_path))
 193                 errx(1, "%s: name too long", target);
 194         to.p_end = to.p_path + strlen(to.p_path);
 195         if (to.p_path == to.p_end) {
 196                 *to.p_end++ = '.';
 197                 *to.p_end = 0;
 198         }
 199         have_trailing_slash = (to.p_end[-1] == '/');
 200         if (have_trailing_slash)
 201                 STRIP_TRAILING_SLASH(to);
 202         to.target_end = to.p_end;
 203
 204         /* Set end of argument list for fts(3). */
 205         argv[argc] = NULL;
 206
 207         /*
 208          * Cp has two distinct cases:
 209          *
 210          * cp [-R] source target
 211          * cp [-R] source1 ... sourceN directory
 212          *
 213          * In both cases, source can be either a file or a directory.
 214          *
 215          * In (1), the target becomes a copy of the source. That is, if the
 216          * source is a file, the target will be a file, and likewise for
 217          * directories.
 218          *
 219          * In (2), the real target is not directory, but "directory/source".
 220          */
 221         r = stat(to.p_path, &to_stat);
 222         if (r == -1 && errno != ENOENT)
 223                 err(1, "%s", to.p_path);
 224         if (r == -1 || !S_ISDIR(to_stat.st_mode)) {
 225                 /*
 226                  * Case (1).  Target is not a directory.
 227                  */
 228                 if (argc > 1)
 229                         errx(1, "%s is not a directory", to.p_path);
 230
 231                 /*
 232                  * Need to detect the case:
 233                  *      cp -R dir foo
 234                  * Where dir is a directory and foo does not exist, where
 235                  * we want pathname concatenations turned on but not for
 236                  * the initial mkdir().
 237                  */
 238                 if (r == -1) {
 239                         if (Rflag && (Lflag || Hflag))
 240                                 stat(*argv, &tmp_stat);
 241                         else
 242                                 lstat(*argv, &tmp_stat);
 243
 244                         if (S_ISDIR(tmp_stat.st_mode) && Rflag)
 245                                 type = DIR_TO_DNE;
 246                         else
 247                                 type = FILE_TO_FILE;
 248                 } else
 249                         type = FILE_TO_FILE;
 250
 251                 if (have_trailing_slash && type == FILE_TO_FILE) {
 252                         if (r == -1) {
 253                                 errx(1, "directory %s does not exist",
 254                                     to.p_path);
 255                         } else
 256                                 errx(1, "%s is not a directory", to.p_path);
 257                 }
 258         } else
 259                 /*
 260                  * Case (2).  Target is a directory.
 261                  */
 262                 type = FILE_TO_DIR;
 263
 264         exit (copy(argv, type, fts_options));
 265 }
 266
 267 /* Does the right thing based on -R + -H/-L/-P */
 268 static int
 269 copy_stat(const char *path, struct stat *sb)
 270 {
 271
 272         /*
 273          * For -R -H/-P, we need to lstat() instead; copy() cares about the link
 274          * itself rather than the target if we're not following links during the
 275          * traversal.
 276          */
 277         if (!Rflag || Lflag)
 278                 return (stat(path, sb));
 279         return (lstat(path, sb));
 280 }
 281
 282
 283 static int
 284 copy(char *argv[], enum op type, int fts_options)
 285 {
 286         struct stat to_stat;
 287         FTS *ftsp;
 288         FTSENT *curr;
 289         int base = 0, dne, badcp, rval;
 290         size_t nlen;
 291         char *p, *target_mid;
 292         mode_t mask, mode;
 293
 294         /*
 295          * Keep an inverted copy of the umask, for use in correcting
 296          * permissions on created directories when not using -p.
 297          */
 298         mask = ~umask(0777);
 299         umask(~mask);
 300
 301         if ((ftsp = fts_open(argv, fts_options, NULL)) == NULL)
 302                 err(1, "fts_open");
 303         for (badcp = rval = 0; errno = 0, (curr = fts_read(ftsp)) != NULL;
 304             badcp = 0) {
 305                 switch (curr->fts_info) {
 306                 case FTS_NS:
 307                 case FTS_DNR:
 308                 case FTS_ERR:
 309                         warnx("%s: %s",
 310                             curr->fts_path, strerror(curr->fts_errno));
 311                         badcp = rval = 1;
 312                         continue;
 313                 case FTS_DC:                    /* Warn, continue. */
 314                         warnx("%s: directory causes a cycle", curr->fts_path);
 315                         badcp = rval = 1;
 316                         continue;
 317                 default:
 318                         ;
 319                 }
 320
 321                 /*
 322                  * If we are in case (2) or (3) above, we need to append the
 323                  * source name to the target name.
 324                  */
 325                 if (type != FILE_TO_FILE) {
 326                         /*
 327                          * Need to remember the roots of traversals to create
 328                          * correct pathnames.  If there's a directory being
 329                          * copied to a non-existent directory, e.g.
 330                          *      cp -R a/dir noexist
 331                          * the resulting path name should be noexist/foo, not
 332                          * noexist/dir/foo (where foo is a file in dir), which
 333                          * is the case where the target exists.
 334                          *
 335                          * Also, check for "..".  This is for correct path
 336                          * concatenation for paths ending in "..", e.g.
 337                          *      cp -R .. /tmp
 338                          * Paths ending in ".." are changed to ".".  This is
 339                          * tricky, but seems the easiest way to fix the problem.
 340                          *
 341                          * XXX
 342                          * Since the first level MUST be FTS_ROOTLEVEL, base
 343                          * is always initialized.
 344                          */
 345                         if (curr->fts_level == FTS_ROOTLEVEL) {
 346                                 if (type != DIR_TO_DNE) {
 347                                         p = strrchr(curr->fts_path, '/');
 348                                         base = (p == NULL) ? 0 :
 349                                             (int)(p - curr->fts_path + 1);
 350
 351                                         if (!strcmp(&curr->fts_path[base],
 352                                             ".."))
 353                                                 base += 1;
 354                                 } else
 355                                         base = curr->fts_pathlen;
 356                         }
 357
 358                         p = &curr->fts_path[base];
 359                         nlen = curr->fts_pathlen - base;
 360                         target_mid = to.target_end;
 361                         if (*p != '/' && target_mid[-1] != '/')
 362                                 *target_mid++ = '/';
 363                         *target_mid = 0;
 364                         if (target_mid - to.p_path + nlen >= PATH_MAX) {
 365                                 warnx("%s%s: name too long (not copied)",
 366                                     to.p_path, p);
 367                                 badcp = rval = 1;
 368                                 continue;
 369                         }
 370                         (void)strncat(target_mid, p, nlen);
 371                         to.p_end = target_mid + nlen;
 372                         *to.p_end = 0;
 373                         STRIP_TRAILING_SLASH(to);
 374                 }
 375
 376                 if (curr->fts_info == FTS_DP) {
 377                         /*
 378                          * We are nearly finished with this directory.  If we
 379                          * didn't actually copy it, or otherwise don't need to
 380                          * change its attributes, then we are done.
 381                          */
 382                         if (!curr->fts_number)
 383                                 continue;
 384                         /*
 385                          * If -p is in effect, set all the attributes.
 386                          * Otherwise, set the correct permissions, limited
 387                          * by the umask.  Optimise by avoiding a chmod()
 388                          * if possible (which is usually the case if we
 389                          * made the directory).  Note that mkdir() does not
 390                          * honour setuid, setgid and sticky bits, but we
 391                          * normally want to preserve them on directories.
 392                          */
 393                         if (pflag) {
 394                                 if (setfile(curr->fts_statp, -1))
 395                                         rval = 1;
 396                                 if (preserve_dir_acls(curr->fts_statp,
 397                                     curr->fts_accpath, to.p_path) != 0)
 398                                         rval = 1;
 399                         } else {
 400                                 mode = curr->fts_statp->st_mode;
 401                                 if ((mode & (S_ISUID | S_ISGID | S_ISTXT)) ||
 402                                     ((mode | S_IRWXU) & mask) != (mode & mask))
 403                                         if (chmod(to.p_path, mode & mask) !=
 404                                             0) {
 405                                                 warn("chmod: %s", to.p_path);
 406                                                 rval = 1;
 407                                         }
 408                         }
 409                         continue;
 410                 }
 411
 412                 /* Not an error but need to remember it happened. */
 413                 if (copy_stat(to.p_path, &to_stat) == -1)
 414                         dne = 1;
 415                 else {
 416                         if (to_stat.st_dev == curr->fts_statp->st_dev &&
 417                             to_stat.st_ino == curr->fts_statp->st_ino) {
 418                                 warnx("%s and %s are identical (not copied).",
 419                                     to.p_path, curr->fts_path);
 420                                 badcp = rval = 1;
 421                                 if (S_ISDIR(curr->fts_statp->st_mode))
 422                                         (void)fts_set(ftsp, curr, FTS_SKIP);
 423                                 continue;
 424                         }
 425                         if (!S_ISDIR(curr->fts_statp->st_mode) &&
 426                             S_ISDIR(to_stat.st_mode)) {
 427                                 warnx("cannot overwrite directory %s with "
 428                                     "non-directory %s",
 429                                     to.p_path, curr->fts_path);
 430                                 badcp = rval = 1;
 431                                 continue;
 432                         }
 433                         dne = 0;
 434                 }
 435
 436                 switch (curr->fts_statp->st_mode & S_IFMT) {
 437                 case S_IFLNK:
 438                         /* Catch special case of a non-dangling symlink. */
 439                         if ((fts_options & FTS_LOGICAL) ||
 440                             ((fts_options & FTS_COMFOLLOW) &&
 441                             curr->fts_level == 0)) {
 442                                 if (copy_file(curr, dne))
 443                                         badcp = rval = 1;
 444                         } else {
 445                                 if (copy_link(curr, !dne))
 446                                         badcp = rval = 1;
 447                         }
 448                         break;
 449                 case S_IFDIR:
 450                         if (!Rflag) {
 451                                 warnx("%s is a directory (not copied).",
 452                                     curr->fts_path);
 453                                 (void)fts_set(ftsp, curr, FTS_SKIP);
 454                                 badcp = rval = 1;
 455                                 break;
 456                         }
 457                         /*
 458                          * If the directory doesn't exist, create the new
 459                          * one with the from file mode plus owner RWX bits,
 460                          * modified by the umask.  Trade-off between being
 461                          * able to write the directory (if from directory is
 462                          * 555) and not causing a permissions race.  If the
 463                          * umask blocks owner writes, we fail.
 464                          */
 465                         if (dne) {
 466                                 if (mkdir(to.p_path,
 467                                     curr->fts_statp->st_mode | S_IRWXU) < 0)
 468                                         err(1, "%s", to.p_path);
 469                         } else if (!S_ISDIR(to_stat.st_mode)) {
 470                                 errno = ENOTDIR;
 471                                 err(1, "%s", to.p_path);
 472                         }
 473                         /*
 474                          * Arrange to correct directory attributes later
 475                          * (in the post-order phase) if this is a new
 476                          * directory, or if the -p flag is in effect.
 477                          */
 478                         curr->fts_number = pflag || dne;
 479                         break;
 480                 case S_IFBLK:
 481                 case S_IFCHR:
 482                         if (Rflag && !sflag) {
 483                                 if (copy_special(curr->fts_statp, !dne))
 484                                         badcp = rval = 1;
 485                         } else {
 486                                 if (copy_file(curr, dne))
 487                                         badcp = rval = 1;
 488                         }
 489                         break;
 490                 case S_IFSOCK:
 491                         warnx("%s is a socket (not copied).",
 492                             curr->fts_path);
 493                         break;
 494                 case S_IFIFO:
 495                         if (Rflag && !sflag) {
 496                                 if (copy_fifo(curr->fts_statp, !dne))
 497                                         badcp = rval = 1;
 498                         } else {
 499                                 if (copy_file(curr, dne))
 500                                         badcp = rval = 1;
 501                         }
 502                         break;
 503                 default:
 504                         if (copy_file(curr, dne))
 505                                 badcp = rval = 1;
 506                         break;
 507                 }
 508                 if (vflag && !badcp)
 509                         (void)printf("%s -> %s\n", curr->fts_path, to.p_path);
 510         }
 511         if (errno)
 512                 err(1, "fts_read");
 513         fts_close(ftsp);
 514         return (rval);
 515 }
 516
 517 static void
 518 siginfo(int sig __unused)
 519 {
 520
 521         info = 1;
 522 }