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