bin/mv/mv.c

   1 /*-
   2  * Copyright (c) 1989, 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  * Ken Smith of The State University of New York at Buffalo.
   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 #include <sys/param.h>
  34 #include <sys/time.h>
  35 #include <sys/wait.h>
  36 #include <sys/stat.h>
  37 #include <sys/mount.h>
  38
  39 #include <err.h>
  40 #include <errno.h>
  41 #include <fcntl.h>
  42 #include <grp.h>
  43 #include <limits.h>
  44 #include <paths.h>
  45 #include <pwd.h>
  46 #include <signal.h>
  47 #include <stdio.h>
  48 #include <stdlib.h>
  49 #include <string.h>
  50 #include <sysexits.h>
  51 #include <unistd.h>
  52
  53 /* Exit code for a failed exec. */
  54 #define EXEC_FAILED 127
  55
  56 #ifndef _PATH_RM
  57 #define _PATH_RM        "/bin/rm"
  58 #endif
  59
  60 static int      fflg, hflg, iflg, nflg, vflg;
  61 static volatile sig_atomic_t info;
  62
  63 static int      copy(const char *, const char *);
  64 static int      do_move(const char *, const char *);
  65 static int      fastcopy(const char *, const char *, struct stat *);
  66 static void     usage(void);
  67 #ifdef SIGINFO
  68 static void     siginfo(int);
  69 #endif
  70
  71 int
  72 main(int argc, char *argv[])
  73 {
  74         size_t baselen, len;
  75         int rval;
  76         char *p, *endp;
  77         struct stat sb;
  78         int ch;
  79         char path[PATH_MAX];
  80
  81         while ((ch = getopt(argc, argv, "fhinv")) != -1)
  82                 switch (ch) {
  83                 case 'h':
  84                         hflg = 1;
  85                         break;
  86                 case 'i':
  87                         iflg = 1;
  88                         fflg = nflg = 0;
  89                         break;
  90                 case 'f':
  91                         fflg = 1;
  92                         iflg = nflg = 0;
  93                         break;
  94                 case 'n':
  95                         nflg = 1;
  96                         fflg = iflg = 0;
  97                         break;
  98                 case 'v':
  99                         vflg = 1;
 100                         break;
 101                 default:
 102                         usage();
 103                 }
 104         argc -= optind;
 105         argv += optind;
 106
 107 #ifdef SIGINFO
 108         signal(SIGINFO, siginfo);
 109 #endif
 110
 111         if (argc < 2)
 112                 usage();
 113
 114         /*
 115          * If the stat on the target fails or the target isn't a directory,
 116          * try the move.  More than 2 arguments is an error in this case.
 117          */
 118         if (stat(argv[argc - 1], &sb) || !S_ISDIR(sb.st_mode)) {
 119                 if (argc > 2)
 120                         usage();
 121                 exit(do_move(argv[0], argv[1]));
 122         }
 123
 124         /*
 125          * If -h was specified, treat the target as a symlink instead of
 126          * directory.
 127          */
 128         if (hflg) {
 129                 if (argc > 2)
 130                         usage();
 131                 if (lstat(argv[1], &sb) == 0 && S_ISLNK(sb.st_mode))
 132                         exit(do_move(argv[0], argv[1]));
 133         }
 134
 135         /* It's a directory, move each file into it. */
 136         if (strlen(argv[argc - 1]) > sizeof(path) - 1)
 137                 errx(1, "%s: destination pathname too long", *argv);
 138         strcpy(path, argv[argc - 1]);
 139         baselen = strlen(path);
 140         endp = &path[baselen];
 141         if (!baselen || *(endp - 1) != '/') {
 142                 *endp++ = '/';
 143                 ++baselen;
 144         }
 145         for (rval = 0; --argc; ++argv) {
 146                 /*
 147                  * Find the last component of the source pathname.  It
 148                  * may have trailing slashes.
 149                  */
 150                 p = *argv + strlen(*argv);
 151                 while (p != *argv && p[-1] == '/')
 152                         --p;
 153                 while (p != *argv && p[-1] != '/')
 154                         --p;
 155
 156                 if ((baselen + (len = strlen(p))) >= PATH_MAX) {
 157                         warnx("%s: destination pathname too long", *argv);
 158                         rval = 1;
 159                 } else {
 160                         memmove(endp, p, (size_t)len + 1);
 161                         if (do_move(*argv, path))
 162                                 rval = 1;
 163                 }
 164         }
 165         exit(rval);
 166 }
 167
 168 static int
 169 do_move(const char *from, const char *to)
 170 {
 171         struct stat sb;
 172         int ask, ch, first;
 173         char modep[15];
 174
 175         /*
 176          * Check access.  If interactive and file exists, ask user if it
 177          * should be replaced.  Otherwise if file exists but isn't writable
 178          * make sure the user wants to clobber it.
 179          */
 180         if (!fflg && !access(to, F_OK)) {
 181
 182                 /* prompt only if source exist */
 183                 if (lstat(from, &sb) == -1) {
 184                         warn("%s", from);
 185                         return (1);
 186                 }
 187
 188 #define YESNO "(y/n [n]) "
 189                 ask = 0;
 190                 if (nflg) {
 191                         if (vflg)
 192                                 printf("%s not overwritten\n", to);
 193                         return (0);
 194                 } else if (iflg) {
 195                         fprintf(stderr, "overwrite %s? %s", to, YESNO);
 196                         ask = 1;
 197                 } else if (access(to, W_OK) && !stat(to, &sb) && isatty(STDIN_FILENO)) {
 198                         strmode(sb.st_mode, modep);
 199                         fprintf(stderr, "override %s%s%s/%s for %s? %s",
 200                             modep + 1, modep[9] == ' ' ? "" : " ",
 201                             user_from_uid((unsigned long)sb.st_uid, 0),
 202                             group_from_gid((unsigned long)sb.st_gid, 0), to, YESNO);
 203                         ask = 1;
 204                 }
 205                 if (ask) {
 206                         first = ch = getchar();
 207                         while (ch != '\n' && ch != EOF)
 208                                 ch = getchar();
 209                         if (first != 'y' && first != 'Y') {
 210                                 fprintf(stderr, "not overwritten\n");
 211                                 return (0);
 212                         }
 213                 }
 214         }
 215         /*
 216          * Rename on FreeBSD will fail with EISDIR and ENOTDIR, before failing
 217          * with EXDEV.  Therefore, copy() doesn't have to perform the checks
 218          * specified in the Step 3 of the POSIX mv specification.
 219          */
 220         if (!rename(from, to)) {
 221                 if (vflg)
 222                         printf("%s -> %s\n", from, to);
 223                 return (0);
 224         }
 225
 226         if (errno == EXDEV) {
 227                 char path[PATH_MAX];
 228                 int target_is_file = 0;
 229
 230                 if (!lstat(to, &sb) && S_ISREG(sb.st_mode))
 231                         target_is_file = 1;
 232                 /*
 233                  * If the source is a symbolic link and is on another
 234                  * filesystem, it can be recreated at the destination.
 235                  */
 236                 if (lstat(from, &sb) == -1) {
 237                         warn("%s", from);
 238                         return (1);
 239                 }
 240                 /* Can't mv(1) directory into a file ever. */
 241                 if (target_is_file && S_ISDIR(sb.st_mode)) {
 242                         warn("cannot overwrite %s with directory", to);
 243                         return (1);
 244                 }
 245                 if (!S_ISLNK(sb.st_mode)) {
 246                         /* Can't mv(1) a mount point. */
 247                         if (realpath(from, path) == NULL) {
 248                                 warn("cannot resolve %s: %s", from, path);
 249                                 return (1);
 250                         }
 251 #ifdef MNAMELEN
 252                         struct statfs sfs;
 253                         if (!statfs(path, &sfs) &&
 254                             !strcmp(path, sfs.f_mntonname)) {
 255                                 warnx("cannot rename a mount point");
 256                                 return (1);
 257                         }
 258 #endif
 259                 }
 260         } else {
 261                 warn("rename %s to %s", from, to);
 262                 return (1);
 263         }
 264
 265         /*
 266          * If rename fails because we're trying to cross devices, and
 267          * it's a regular file, do the copy internally; otherwise, use
 268          * cp and rm.
 269          */
 270         if (lstat(from, &sb)) {
 271                 warn("%s", from);
 272                 return (1);
 273         }
 274         return (S_ISREG(sb.st_mode) ?
 275             fastcopy(from, to, &sb) : copy(from, to));
 276 }
 277
 278 static int
 279 fastcopy(const char *from, const char *to, struct stat *sbp)
 280 {
 281         struct timeval tval[2];
 282         static u_int blen = MAXPHYS;
 283         static char *bp = NULL;
 284         mode_t oldmode;
 285         int from_fd, to_fd;
 286         ssize_t nread;
 287
 288         if ((from_fd = open(from, O_RDONLY, 0)) < 0) {
 289                 warn("fastcopy: open() failed (from): %s", from);
 290                 return (1);
 291         }
 292         if (bp == NULL && (bp = malloc((size_t)blen)) == NULL) {
 293                 warnx("malloc(%u) failed", blen);
 294                 return (1);
 295         }
 296         while ((to_fd =
 297             open(to, O_CREAT | O_EXCL | O_TRUNC | O_WRONLY, 0)) < 0) {
 298                 if (errno == EEXIST && unlink(to) == 0)
 299                         continue;
 300                 warn("fastcopy: open() failed (to): %s", to);
 301                 close(from_fd);
 302                 return (1);
 303         }
 304         while ((nread = read(from_fd, bp, (size_t)blen)) > 0)
 305                 if (write(to_fd, bp, (size_t)nread) != nread) {
 306                         warn("fastcopy: write() failed: %s", to);
 307                         goto err;
 308                 }
 309         if (nread < 0) {
 310                 warn("fastcopy: read() failed: %s", from);
 311 err:            if (unlink(to))
 312                         warn("%s: remove", to);
 313                 close(from_fd);
 314                 close(to_fd);
 315                 return (1);
 316         }
 317
 318         oldmode = sbp->st_mode & ALLPERMS;
 319         if (fchown(to_fd, sbp->st_uid, sbp->st_gid)) {
 320                 warn("%s: set owner/group (was: %lu/%lu)", to,
 321                     (u_long)sbp->st_uid, (u_long)sbp->st_gid);
 322                 if (oldmode & (S_ISUID | S_ISGID)) {
 323                         warnx(
 324 "%s: owner/group changed; clearing suid/sgid (mode was 0%03o)",
 325                             to, oldmode);
 326                         sbp->st_mode &= ~(S_ISUID | S_ISGID);
 327                 }
 328         }
 329         if (fchmod(to_fd, sbp->st_mode))
 330                 warn("%s: set mode (was: 0%03o)", to, oldmode);
 331
 332         close(from_fd);
 333         /*
 334          * XXX
 335          * NFS doesn't support chflags; ignore errors unless there's reason
 336          * to believe we're losing bits.  (Note, this still won't be right
 337          * if the server supports flags and we were trying to *remove* flags
 338          * on a file that we copied, i.e., that we didn't create.)
 339          */
 340         errno = 0;
 341 #ifdef _ST_FLAGS_PRESENT_
 342         if (fchflags(to_fd, sbp->st_flags))
 343                 if (errno != EOPNOTSUPP || sbp->st_flags != 0)
 344                         warn("%s: set flags (was: 0%07o)", to, sbp->st_flags);
 345 #endif
 346
 347         tval[0].tv_sec = sbp->st_atime;
 348         tval[1].tv_sec = sbp->st_mtime;
 349         tval[0].tv_usec = tval[1].tv_usec = 0;
 350         if (utimes(to, tval))
 351                 warn("%s: set times", to);
 352
 353         if (close(to_fd)) {
 354                 warn("%s", to);
 355                 return (1);
 356         }
 357
 358         if (unlink(from)) {
 359                 warn("%s: remove", from);
 360                 return (1);
 361         }
 362         if (vflg)
 363                 printf("%s -> %s\n", from, to);
 364         return (0);
 365 }
 366
 367 static int
 368 copy(const char *from, const char *to)
 369 {
 370         struct stat sb;
 371         int status;
 372         pid_t pid;
 373
 374         if (lstat(to, &sb) == 0) {
 375                 /* Destination path exists. */
 376                 if (S_ISDIR(sb.st_mode)) {
 377                         if (rmdir(to) != 0) {
 378                                 warn("rmdir %s", to);
 379                                 return (1);
 380                         }
 381                 } else {
 382                         if (unlink(to) != 0) {
 383                                 warn("unlink %s", to);
 384                                 return (1);
 385                         }
 386                 }
 387         } else if (errno != ENOENT) {
 388                 warn("%s", to);
 389                 return (1);
 390         }
 391
 392         /* Copy source to destination. */
 393         if (!(pid = vfork())) {
 394                 execl(_PATH_CP, "mv", vflg ? "-PRpv" : "-PRp", "--", from, to,
 395                     NULL);
 396                 _exit(EXEC_FAILED);
 397         }
 398         if (waitpid(pid, &status, 0) == -1) {
 399                 warn("%s %s %s: waitpid", _PATH_CP, from, to);
 400                 return (1);
 401         }
 402         if (!WIFEXITED(status)) {
 403                 warnx("%s %s %s: did not terminate normally",
 404                     _PATH_CP, from, to);
 405                 return (1);
 406         }
 407         switch (WEXITSTATUS(status)) {
 408         case 0:
 409                 break;
 410         case EXEC_FAILED:
 411                 warnx("%s %s %s: exec failed", _PATH_CP, from, to);
 412                 return (1);
 413         default:
 414                 warnx("%s %s %s: terminated with %d (non-zero) status",
 415                     _PATH_CP, from, to, WEXITSTATUS(status));
 416                 return (1);
 417         }
 418
 419         /* Delete the source. */
 420         if (!(pid = vfork())) {
 421                 execl(_PATH_RM, "mv", "-rf", "--", from, NULL);
 422                 _exit(EXEC_FAILED);
 423         }
 424         if (waitpid(pid, &status, 0) == -1) {
 425                 warn("%s %s: waitpid", _PATH_RM, from);
 426                 return (1);
 427         }
 428         if (!WIFEXITED(status)) {
 429                 warnx("%s %s: did not terminate normally", _PATH_RM, from);
 430                 return (1);
 431         }
 432         switch (WEXITSTATUS(status)) {
 433         case 0:
 434                 break;
 435         case EXEC_FAILED:
 436                 warnx("%s %s: exec failed", _PATH_RM, from);
 437                 return (1);
 438         default:
 439                 warnx("%s %s: terminated with %d (non-zero) status",
 440                     _PATH_RM, from, WEXITSTATUS(status));
 441                 return (1);
 442         }
 443         return (0);
 444 }
 445
 446 static void
 447 usage(void)
 448 {
 449
 450         fprintf(stderr, "%s\n%s\n",
 451                 "usage: mv [-f | -i | -n] [-hv] source target",
 452                 "       mv [-f | -i | -n] [-v] source ... directory");
 453         exit(EX_USAGE);
 454 }
 455
 456 #ifdef SIGINFO
 457 static void
 458 siginfo(int notused __unused)
 459 {
 460         info = 1;
 461 }
 462 #endif