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 static char emptystring[] = "";
  69
  70 PATH_T to = { to.p_path, emptystring, "" };
  71
  72 int fflag, iflag, lflag, nflag, pflag, vflag;
  73 static int Rflag, rflag;
  74 volatile sig_atomic_t info;
  75
  76 enum op { FILE_TO_FILE, FILE_TO_DIR, DIR_TO_DNE };
  77
  78 static int copy(char *[], enum op, int);
  79 static int mastercmp (const FTSENT * const *, const FTSENT * const *);
  80 static void siginfo (int);
  81
  82 int
  83 main(int argc, char *argv[])
  84 {
  85         struct stat to_stat, tmp_stat;
  86         enum op type;
  87         int Hflag, Lflag, Pflag, ch, fts_options, r, have_trailing_slash;
  88         char *target;
  89
  90         fts_options = FTS_NOCHDIR | FTS_PHYSICAL;
  91         Hflag = Lflag = Pflag = 0;
  92         while ((ch = getopt(argc, argv, "HLPRafilnprvx")) != -1)
  93                 switch (ch) {
  94                 case 'H':
  95                         Hflag = 1;
  96                         Lflag = Pflag = 0;
  97                         break;
  98                 case 'L':
  99                         Lflag = 1;
 100                         Hflag = Pflag = 0;
 101                         break;
 102                 case 'P':
 103                         Pflag = 1;
 104                         Hflag = Lflag = 0;
 105                         break;
 106                 case 'R':
 107                         Rflag = 1;
 108                         break;
 109                 case 'a':
 110                         Pflag = 1;
 111                         pflag = 1;
 112                         Rflag = 1;
 113                         Hflag = Lflag = 0;
 114                         break;
 115                 case 'f':
 116                         fflag = 1;
 117                         iflag = nflag = 0;
 118                         break;
 119                 case 'i':
 120                         iflag = 1;
 121                         fflag = nflag = 0;
 122                         break;
 123                 case 'l':
 124                         lflag = 1;
 125                         break;
 126                 case 'n':
 127                         nflag = 1;
 128                         fflag = iflag = 0;
 129                         break;
 130                 case 'p':
 131                         pflag = 1;
 132                         break;
 133                 case 'r':
 134                         rflag = Lflag = 1;
 135                         Hflag = Pflag = 0;
 136                         break;
 137                 case 'v':
 138                         vflag = 1;
 139                         break;
 140                 case 'x':
 141                         fts_options |= FTS_XDEV;
 142                         break;
 143                 default:
 144                         usage();
 145                         break;
 146                 }
 147         argc -= optind;
 148         argv += optind;
 149
 150         if (argc < 2)
 151                 usage();
 152
 153         if (Rflag && rflag)
 154                 errx(1, "the -R and -r options may not be specified together");
 155         if (rflag)
 156                 Rflag = 1;
 157         if (Rflag) {
 158                 if (Hflag)
 159                         fts_options |= FTS_COMFOLLOW;
 160                 if (Lflag) {
 161                         fts_options &= ~FTS_PHYSICAL;
 162                         fts_options |= FTS_LOGICAL;
 163                 }
 164         } else {
 165                 fts_options &= ~FTS_PHYSICAL;
 166                 fts_options |= FTS_LOGICAL | FTS_COMFOLLOW;
 167         }
 168         signal(SIGINFO, siginfo);
 169
 170         /* Save the target base in "to". */
 171         target = argv[--argc];
 172         if (strlcpy(to.p_path, target, sizeof(to.p_path)) >= sizeof(to.p_path))
 173                 errx(1, "%s: name too long", target);
 174         to.p_end = to.p_path + strlen(to.p_path);
 175         if (to.p_path == to.p_end) {
 176                 *to.p_end++ = '.';
 177                 *to.p_end = 0;
 178         }
 179         have_trailing_slash = (to.p_end[-1] == '/');
 180         if (have_trailing_slash)
 181                 STRIP_TRAILING_SLASH(to);
 182         to.target_end = to.p_end;
 183
 184         /* Set end of argument list for fts(3). */
 185         argv[argc] = NULL;
 186
 187         /*
 188          * Cp has two distinct cases:
 189          *
 190          * cp [-R] source target
 191          * cp [-R] source1 ... sourceN directory
 192          *
 193          * In both cases, source can be either a file or a directory.
 194          *
 195          * In (1), the target becomes a copy of the source. That is, if the
 196          * source is a file, the target will be a file, and likewise for
 197          * directories.
 198          *
 199          * In (2), the real target is not directory, but "directory/source".
 200          */
 201         r = stat(to.p_path, &to_stat);
 202         if (r == -1 && errno != ENOENT)
 203                 err(1, "%s", to.p_path);
 204         if (r == -1 || !S_ISDIR(to_stat.st_mode)) {
 205                 /*
 206                  * Case (1).  Target is not a directory.
 207                  */
 208                 if (argc > 1)
 209                         errx(1, "%s is not a directory", to.p_path);
 210
 211                 /*
 212                  * Need to detect the case:
 213                  *      cp -R dir foo
 214                  * Where dir is a directory and foo does not exist, where
 215                  * we want pathname concatenations turned on but not for
 216                  * the initial mkdir().
 217                  */
 218                 if (r == -1) {
 219                         if (Rflag && (Lflag || Hflag))
 220                                 stat(*argv, &tmp_stat);
 221                         else
 222                                 lstat(*argv, &tmp_stat);
 223
 224                         if (S_ISDIR(tmp_stat.st_mode) && Rflag)
 225                                 type = DIR_TO_DNE;
 226                         else
 227                                 type = FILE_TO_FILE;
 228                 } else
 229                         type = FILE_TO_FILE;
 230
 231                 if (have_trailing_slash && type == FILE_TO_FILE) {
 232                         if (r == -1)
 233                                 errx(1, "directory %s does not exist",
 234                                      to.p_path);
 235                         else
 236                                 errx(1, "%s is not a directory", to.p_path);
 237                 }
 238         } else
 239                 /*
 240                  * Case (2).  Target is a directory.
 241                  */
 242                 type = FILE_TO_DIR;
 243
 244         exit (copy(argv, type, fts_options));
 245 }
 246
 247 static int
 248 copy(char *argv[], enum op type, int fts_options)
 249 {
 250         struct stat to_stat;
 251         FTS *ftsp;
 252         FTSENT *curr;
 253         int base = 0, dne, badcp, rval;
 254         size_t nlen;
 255         char *p, *target_mid;
 256         mode_t mask, mode;
 257
 258         /*
 259          * Keep an inverted copy of the umask, for use in correcting
 260          * permissions on created directories when not using -p.
 261          */
 262         mask = ~umask(0777);
 263         umask(~mask);
 264
 265         if ((ftsp = fts_open(argv, fts_options, mastercmp)) == NULL)
 266                 err(1, "fts_open");
 267         for (badcp = rval = 0; (curr = fts_read(ftsp)) != NULL; badcp = 0) {
 268                 switch (curr->fts_info) {
 269                 case FTS_NS:
 270                 case FTS_DNR:
 271                 case FTS_ERR:
 272                         warnx("%s: %s",
 273                             curr->fts_path, strerror(curr->fts_errno));
 274                         rval = 1;
 275                         continue;
 276                 case FTS_DC:                    /* Warn, continue. */
 277                         warnx("%s: directory causes a cycle", curr->fts_path);
 278                         rval = 1;
 279                         continue;
 280                 default:
 281                         ;
 282                 }
 283
 284                 /*
 285                  * If we are in case (2) or (3) above, we need to append the
 286                  * source name to the target name.
 287                  */
 288                 if (type != FILE_TO_FILE) {
 289                         /*
 290                          * Need to remember the roots of traversals to create
 291                          * correct pathnames.  If there's a directory being
 292                          * copied to a non-existent directory, e.g.
 293                          *      cp -R a/dir noexist
 294                          * the resulting path name should be noexist/foo, not
 295                          * noexist/dir/foo (where foo is a file in dir), which
 296                          * is the case where the target exists.
 297                          *
 298                          * Also, check for "..".  This is for correct path
 299                          * concatenation for paths ending in "..", e.g.
 300                          *      cp -R .. /tmp
 301                          * Paths ending in ".." are changed to ".".  This is
 302                          * tricky, but seems the easiest way to fix the problem.
 303                          *
 304                          * XXX
 305                          * Since the first level MUST be FTS_ROOTLEVEL, base
 306                          * is always initialized.
 307                          */
 308                         if (curr->fts_level == FTS_ROOTLEVEL) {
 309                                 if (type != DIR_TO_DNE) {
 310                                         p = strrchr(curr->fts_path, '/');
 311                                         base = (p == NULL) ? 0 :
 312                                             (int)(p - curr->fts_path + 1);
 313
 314                                         if (!strcmp(&curr->fts_path[base],
 315                                             ".."))
 316                                                 base += 1;
 317                                 } else
 318                                         base = curr->fts_pathlen;
 319                         }
 320
 321                         p = &curr->fts_path[base];
 322                         nlen = curr->fts_pathlen - base;
 323                         target_mid = to.target_end;
 324                         if (*p != '/' && target_mid[-1] != '/')
 325                                 *target_mid++ = '/';
 326                         *target_mid = 0;
 327                         if (target_mid - to.p_path + nlen >= PATH_MAX) {
 328                                 warnx("%s%s: name too long (not copied)",
 329                                     to.p_path, p);
 330                                 rval = 1;
 331                                 continue;
 332                         }
 333                         strncat(target_mid, p, nlen);
 334                         to.p_end = target_mid + nlen;
 335                         *to.p_end = 0;
 336                         STRIP_TRAILING_SLASH(to);
 337                 }
 338
 339                 if (curr->fts_info == FTS_DP) {
 340                         /*
 341                          * We are nearly finished with this directory.  If we
 342                          * didn't actually copy it, or otherwise don't need to
 343                          * change its attributes, then we are done.
 344                          */
 345                         if (!curr->fts_number)
 346                                 continue;
 347                         /*
 348                          * If -p is in effect, set all the attributes.
 349                          * Otherwise, set the correct permissions, limited
 350                          * by the umask.  Optimise by avoiding a chmod()
 351                          * if possible (which is usually the case if we
 352                          * made the directory).  Note that mkdir() does not
 353                          * honour setuid, setgid and sticky bits, but we
 354                          * normally want to preserve them on directories.
 355                          */
 356                         if (pflag) {
 357                                 if (setfile(curr->fts_statp, -1))
 358                                     rval = 1;
 359                         } else {
 360                                 mode = curr->fts_statp->st_mode;
 361                                 if ((mode & (S_ISUID | S_ISGID | S_ISTXT)) ||
 362                                     ((mode | S_IRWXU) & mask) != (mode & mask))
 363                                         if (chmod(to.p_path, mode & mask) != 0){
 364                                                 warn("chmod: %s", to.p_path);
 365                                                 rval = 1;
 366                                         }
 367                         }
 368                         continue;
 369                 }
 370
 371                 /* Not an error but need to remember it happened */
 372                 if (stat(to.p_path, &to_stat) == -1)
 373                         dne = 1;
 374                 else {
 375                         if (to_stat.st_dev == curr->fts_statp->st_dev &&
 376                             to_stat.st_ino == curr->fts_statp->st_ino) {
 377                                 warnx("%s and %s are identical (not copied).",
 378                                     to.p_path, curr->fts_path);
 379                                 rval = 1;
 380                                 if (S_ISDIR(curr->fts_statp->st_mode))
 381                                         fts_set(ftsp, curr, FTS_SKIP);
 382                                 continue;
 383                         }
 384                         if (!S_ISDIR(curr->fts_statp->st_mode) &&
 385                             S_ISDIR(to_stat.st_mode)) {
 386                                 warnx("cannot overwrite directory %s with "
 387                                     "non-directory %s",
 388                                     to.p_path, curr->fts_path);
 389                                 rval = 1;
 390                                 continue;
 391                         }
 392                         dne = 0;
 393                 }
 394
 395                 switch (curr->fts_statp->st_mode & S_IFMT) {
 396                 case S_IFLNK:
 397                         /* Catch special case of a non-dangling symlink */
 398                         if ((fts_options & FTS_LOGICAL) ||
 399                             ((fts_options & FTS_COMFOLLOW) &&
 400                             curr->fts_level == 0)) {
 401                                 if (copy_file(curr, dne))
 402                                         badcp = rval = 1;
 403                         } else {
 404                                 if (copy_link(curr, !dne))
 405                                         badcp = rval = 1;
 406                         }
 407                         break;
 408                 case S_IFDIR:
 409                         if (!Rflag) {
 410                                 warnx("%s is a directory (not copied).",
 411                                     curr->fts_path);
 412                                 fts_set(ftsp, curr, FTS_SKIP);
 413                                 badcp = rval = 1;
 414                                 break;
 415                         }
 416                         /*
 417                          * If the directory doesn't exist, create the new
 418                          * one with the from file mode plus owner RWX bits,
 419                          * modified by the umask.  Trade-off between being
 420                          * able to write the directory (if from directory is
 421                          * 555) and not causing a permissions race.  If the
 422                          * umask blocks owner writes, we fail..
 423                          */
 424                         if (dne) {
 425                                 if (mkdir(to.p_path,
 426                                     curr->fts_statp->st_mode | S_IRWXU) < 0)
 427                                         err(1, "%s", to.p_path);
 428                         } else if (!S_ISDIR(to_stat.st_mode)) {
 429                                 errno = ENOTDIR;
 430                                 err(1, "%s", to.p_path);
 431                         }
 432                         /*
 433                          * Arrange to correct directory attributes later
 434                          * (in the post-order phase) if this is a new
 435                          * directory, or if the -p flag is in effect.
 436                          */
 437                         curr->fts_number = pflag || dne;
 438                         break;
 439                 case S_IFBLK:
 440                 case S_IFCHR:
 441                         if (Rflag) {
 442                                 if (copy_special(curr->fts_statp, !dne))
 443                                         badcp = rval = 1;
 444                         } else {
 445                                 if (copy_file(curr, dne))
 446                                         badcp = rval = 1;
 447                         }
 448                         break;
 449                 case S_IFSOCK:
 450                         warnx("%s is a socket (not copied).",
 451                                     curr->fts_path);
 452                         break;
 453                 case S_IFIFO:
 454                         if (Rflag) {
 455                                 if (copy_fifo(curr->fts_statp, !dne))
 456                                         badcp = rval = 1;
 457                         } else {
 458                                 if (copy_file(curr, dne))
 459                                         badcp = rval = 1;
 460                         }
 461                         break;
 462                 default:
 463                         if (copy_file(curr, dne))
 464                                 badcp = rval = 1;
 465                         break;
 466                 }
 467                 if (vflag && !badcp)
 468                         printf("%s -> %s\n", curr->fts_path, to.p_path);
 469         }
 470         if (errno)
 471                 err(1, "fts_read");
 472         fts_close(ftsp);
 473         return (rval);
 474 }
 475
 476 /*
 477  * mastercmp --
 478  *      The comparison function for the copy order.  The order is to copy
 479  *      non-directory files before directory files.  The reason for this
 480  *      is because files tend to be in the same cylinder group as their
 481  *      parent directory, whereas directories tend not to be.  Copying the
 482  *      files first reduces seeking.
 483  */
 484 static int
 485 mastercmp(const FTSENT * const *a, const FTSENT * const *b)
 486 {
 487         int a_info, b_info;
 488
 489         a_info = (*a)->fts_info;
 490         if (a_info == FTS_ERR || a_info == FTS_NS || a_info == FTS_DNR)
 491                 return (0);
 492         b_info = (*b)->fts_info;
 493         if (b_info == FTS_ERR || b_info == FTS_NS || b_info == FTS_DNR)
 494                 return (0);
 495         if (a_info == FTS_D)
 496                 return (-1);
 497         if (b_info == FTS_D)
 498                 return (1);
 499         return (0);
 500 }
 501
 502 static void
 503 siginfo(int sig __unused)
 504 {
 505
 506         info = 1;
 507 }