bin/cp/cp.c

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