xref: /freebsd/bin/mv/mv.c (revision 4cd9b24e478b38e4e497f3ab98e09d6a00a5390d)
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  * 4. 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 #if 0
34 #ifndef lint
35 static char const copyright[] =
36 "@(#) Copyright (c) 1989, 1993, 1994\n\
37 	The Regents of the University of California.  All rights reserved.\n";
38 #endif /* not lint */
39 
40 #ifndef lint
41 static char sccsid[] = "@(#)mv.c	8.2 (Berkeley) 4/2/94";
42 #endif /* not lint */
43 #endif
44 #include <sys/cdefs.h>
45 __FBSDID("$FreeBSD$");
46 
47 #include <sys/types.h>
48 #include <sys/acl.h>
49 #include <sys/param.h>
50 #include <sys/time.h>
51 #include <sys/wait.h>
52 #include <sys/stat.h>
53 #include <sys/mount.h>
54 
55 #include <err.h>
56 #include <errno.h>
57 #include <fcntl.h>
58 #include <grp.h>
59 #include <limits.h>
60 #include <paths.h>
61 #include <pwd.h>
62 #include <stdio.h>
63 #include <stdlib.h>
64 #include <string.h>
65 #include <sysexits.h>
66 #include <unistd.h>
67 
68 /* Exit code for a failed exec. */
69 #define EXEC_FAILED 127
70 
71 static int	fflg, hflg, iflg, nflg, vflg;
72 
73 static int	copy(const char *, const char *);
74 static int	do_move(const char *, const char *);
75 static int	fastcopy(const char *, const char *, struct stat *);
76 static void	usage(void);
77 static void	preserve_fd_acls(int source_fd, int dest_fd, const char *source_path,
78 		    const char *dest_path);
79 
80 int
81 main(int argc, char *argv[])
82 {
83 	size_t baselen, len;
84 	int rval;
85 	char *p, *endp;
86 	struct stat sb;
87 	int ch;
88 	char path[PATH_MAX];
89 
90 	while ((ch = getopt(argc, argv, "fhinv")) != -1)
91 		switch (ch) {
92 		case 'h':
93 			hflg = 1;
94 			break;
95 		case 'i':
96 			iflg = 1;
97 			fflg = nflg = 0;
98 			break;
99 		case 'f':
100 			fflg = 1;
101 			iflg = nflg = 0;
102 			break;
103 		case 'n':
104 			nflg = 1;
105 			fflg = iflg = 0;
106 			break;
107 		case 'v':
108 			vflg = 1;
109 			break;
110 		default:
111 			usage();
112 		}
113 	argc -= optind;
114 	argv += optind;
115 
116 	if (argc < 2)
117 		usage();
118 
119 	/*
120 	 * If the stat on the target fails or the target isn't a directory,
121 	 * try the move.  More than 2 arguments is an error in this case.
122 	 */
123 	if (stat(argv[argc - 1], &sb) || !S_ISDIR(sb.st_mode)) {
124 		if (argc > 2)
125 			errx(1, "%s is not a directory", argv[argc - 1]);
126 		exit(do_move(argv[0], argv[1]));
127 	}
128 
129 	/*
130 	 * If -h was specified, treat the target as a symlink instead of
131 	 * directory.
132 	 */
133 	if (hflg) {
134 		if (argc > 2)
135 			usage();
136 		if (lstat(argv[1], &sb) == 0 && S_ISLNK(sb.st_mode))
137 			exit(do_move(argv[0], argv[1]));
138 	}
139 
140 	/* It's a directory, move each file into it. */
141 	if (strlen(argv[argc - 1]) > sizeof(path) - 1)
142 		errx(1, "%s: destination pathname too long", *argv);
143 	(void)strcpy(path, argv[argc - 1]);
144 	baselen = strlen(path);
145 	endp = &path[baselen];
146 	if (!baselen || *(endp - 1) != '/') {
147 		*endp++ = '/';
148 		++baselen;
149 	}
150 	for (rval = 0; --argc; ++argv) {
151 		/*
152 		 * Find the last component of the source pathname.  It
153 		 * may have trailing slashes.
154 		 */
155 		p = *argv + strlen(*argv);
156 		while (p != *argv && p[-1] == '/')
157 			--p;
158 		while (p != *argv && p[-1] != '/')
159 			--p;
160 
161 		if ((baselen + (len = strlen(p))) >= PATH_MAX) {
162 			warnx("%s: destination pathname too long", *argv);
163 			rval = 1;
164 		} else {
165 			memmove(endp, p, (size_t)len + 1);
166 			if (do_move(*argv, path))
167 				rval = 1;
168 		}
169 	}
170 	exit(rval);
171 }
172 
173 static int
174 do_move(const char *from, const char *to)
175 {
176 	struct stat sb;
177 	int ask, ch, first;
178 	char modep[15];
179 
180 	/*
181 	 * Check access.  If interactive and file exists, ask user if it
182 	 * should be replaced.  Otherwise if file exists but isn't writable
183 	 * make sure the user wants to clobber it.
184 	 */
185 	if (!fflg && !access(to, F_OK)) {
186 
187 		/* prompt only if source exist */
188 	        if (lstat(from, &sb) == -1) {
189 			warn("%s", from);
190 			return (1);
191 		}
192 
193 #define YESNO "(y/n [n]) "
194 		ask = 0;
195 		if (nflg) {
196 			if (vflg)
197 				printf("%s not overwritten\n", to);
198 			return (0);
199 		} else if (iflg) {
200 			(void)fprintf(stderr, "overwrite %s? %s", to, YESNO);
201 			ask = 1;
202 		} else if (access(to, W_OK) && !stat(to, &sb) && isatty(STDIN_FILENO)) {
203 			strmode(sb.st_mode, modep);
204 			(void)fprintf(stderr, "override %s%s%s/%s for %s? %s",
205 			    modep + 1, modep[9] == ' ' ? "" : " ",
206 			    user_from_uid((unsigned long)sb.st_uid, 0),
207 			    group_from_gid((unsigned long)sb.st_gid, 0), to, YESNO);
208 			ask = 1;
209 		}
210 		if (ask) {
211 			first = ch = getchar();
212 			while (ch != '\n' && ch != EOF)
213 				ch = getchar();
214 			if (first != 'y' && first != 'Y') {
215 				(void)fprintf(stderr, "not overwritten\n");
216 				return (0);
217 			}
218 		}
219 	}
220 	/*
221 	 * Rename on FreeBSD will fail with EISDIR and ENOTDIR, before failing
222 	 * with EXDEV.  Therefore, copy() doesn't have to perform the checks
223 	 * specified in the Step 3 of the POSIX mv specification.
224 	 */
225 	if (!rename(from, to)) {
226 		if (vflg)
227 			printf("%s -> %s\n", from, to);
228 		return (0);
229 	}
230 
231 	if (errno == EXDEV) {
232 		struct statfs sfs;
233 		char path[PATH_MAX];
234 
235 		/*
236 		 * If the source is a symbolic link and is on another
237 		 * filesystem, it can be recreated at the destination.
238 		 */
239 		if (lstat(from, &sb) == -1) {
240 			warn("%s", from);
241 			return (1);
242 		}
243 		if (!S_ISLNK(sb.st_mode)) {
244 			/* Can't mv(1) a mount point. */
245 			if (realpath(from, path) == NULL) {
246 				warn("cannot resolve %s: %s", from, path);
247 				return (1);
248 			}
249 			if (!statfs(path, &sfs) &&
250 			    !strcmp(path, sfs.f_mntonname)) {
251 				warnx("cannot rename a mount point");
252 				return (1);
253 			}
254 		}
255 	} else {
256 		warn("rename %s to %s", from, to);
257 		return (1);
258 	}
259 
260 	/*
261 	 * If rename fails because we're trying to cross devices, and
262 	 * it's a regular file, do the copy internally; otherwise, use
263 	 * cp and rm.
264 	 */
265 	if (lstat(from, &sb)) {
266 		warn("%s", from);
267 		return (1);
268 	}
269 	return (S_ISREG(sb.st_mode) ?
270 	    fastcopy(from, to, &sb) : copy(from, to));
271 }
272 
273 static int
274 fastcopy(const char *from, const char *to, struct stat *sbp)
275 {
276 	struct timespec ts[2];
277 	static u_int blen = MAXPHYS;
278 	static char *bp = NULL;
279 	mode_t oldmode;
280 	int nread, from_fd, to_fd;
281 	struct stat tsb;
282 
283 	if ((from_fd = open(from, O_RDONLY, 0)) < 0) {
284 		warn("fastcopy: open() failed (from): %s", from);
285 		return (1);
286 	}
287 	if (bp == NULL && (bp = malloc((size_t)blen)) == NULL) {
288 		warnx("malloc(%u) failed", blen);
289 		return (1);
290 	}
291 	while ((to_fd =
292 	    open(to, O_CREAT | O_EXCL | O_TRUNC | O_WRONLY, 0)) < 0) {
293 		if (errno == EEXIST && unlink(to) == 0)
294 			continue;
295 		warn("fastcopy: open() failed (to): %s", to);
296 		(void)close(from_fd);
297 		return (1);
298 	}
299 	while ((nread = read(from_fd, bp, (size_t)blen)) > 0)
300 		if (write(to_fd, bp, (size_t)nread) != nread) {
301 			warn("fastcopy: write() failed: %s", to);
302 			goto err;
303 		}
304 	if (nread < 0) {
305 		warn("fastcopy: read() failed: %s", from);
306 err:		if (unlink(to))
307 			warn("%s: remove", to);
308 		(void)close(from_fd);
309 		(void)close(to_fd);
310 		return (1);
311 	}
312 
313 	oldmode = sbp->st_mode & ALLPERMS;
314 	if (fchown(to_fd, sbp->st_uid, sbp->st_gid)) {
315 		warn("%s: set owner/group (was: %lu/%lu)", to,
316 		    (u_long)sbp->st_uid, (u_long)sbp->st_gid);
317 		if (oldmode & (S_ISUID | S_ISGID)) {
318 			warnx(
319 "%s: owner/group changed; clearing suid/sgid (mode was 0%03o)",
320 			    to, oldmode);
321 			sbp->st_mode &= ~(S_ISUID | S_ISGID);
322 		}
323 	}
324 	if (fchmod(to_fd, sbp->st_mode))
325 		warn("%s: set mode (was: 0%03o)", to, oldmode);
326 	/*
327 	 * POSIX 1003.2c states that if _POSIX_ACL_EXTENDED is in effect
328 	 * for dest_file, then its ACLs shall reflect the ACLs of the
329 	 * source_file.
330 	 */
331 	preserve_fd_acls(from_fd, to_fd, from, to);
332 	(void)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 	if (fstat(to_fd, &tsb) == 0) {
341 		if ((sbp->st_flags  & ~UF_ARCHIVE) !=
342 		    (tsb.st_flags & ~UF_ARCHIVE)) {
343 			if (fchflags(to_fd,
344 			    sbp->st_flags | (tsb.st_flags & UF_ARCHIVE)))
345 				if (errno != EOPNOTSUPP ||
346 				    ((sbp->st_flags & ~UF_ARCHIVE) != 0))
347 					warn("%s: set flags (was: 0%07o)",
348 					    to, sbp->st_flags);
349 		}
350 	} else
351 		warn("%s: cannot stat", to);
352 
353 	ts[0] = sbp->st_atim;
354 	ts[1] = sbp->st_mtim;
355 	if (futimens(to_fd, ts))
356 		warn("%s: set times", to);
357 
358 	if (close(to_fd)) {
359 		warn("%s", to);
360 		return (1);
361 	}
362 
363 	if (unlink(from)) {
364 		warn("%s: remove", from);
365 		return (1);
366 	}
367 	if (vflg)
368 		printf("%s -> %s\n", from, to);
369 	return (0);
370 }
371 
372 static int
373 copy(const char *from, const char *to)
374 {
375 	struct stat sb;
376 	int pid, status;
377 
378 	if (lstat(to, &sb) == 0) {
379 		/* Destination path exists. */
380 		if (S_ISDIR(sb.st_mode)) {
381 			if (rmdir(to) != 0) {
382 				warn("rmdir %s", to);
383 				return (1);
384 			}
385 		} else {
386 			if (unlink(to) != 0) {
387 				warn("unlink %s", to);
388 				return (1);
389 			}
390 		}
391 	} else if (errno != ENOENT) {
392 		warn("%s", to);
393 		return (1);
394 	}
395 
396 	/* Copy source to destination. */
397 	if (!(pid = vfork())) {
398 		execl(_PATH_CP, "mv", vflg ? "-PRpv" : "-PRp", "--", from, to,
399 		    (char *)NULL);
400 		_exit(EXEC_FAILED);
401 	}
402 	if (waitpid(pid, &status, 0) == -1) {
403 		warn("%s %s %s: waitpid", _PATH_CP, from, to);
404 		return (1);
405 	}
406 	if (!WIFEXITED(status)) {
407 		warnx("%s %s %s: did not terminate normally",
408 		    _PATH_CP, from, to);
409 		return (1);
410 	}
411 	switch (WEXITSTATUS(status)) {
412 	case 0:
413 		break;
414 	case EXEC_FAILED:
415 		warnx("%s %s %s: exec failed", _PATH_CP, from, to);
416 		return (1);
417 	default:
418 		warnx("%s %s %s: terminated with %d (non-zero) status",
419 		    _PATH_CP, from, to, WEXITSTATUS(status));
420 		return (1);
421 	}
422 
423 	/* Delete the source. */
424 	if (!(pid = vfork())) {
425 		execl(_PATH_RM, "mv", "-rf", "--", from, (char *)NULL);
426 		_exit(EXEC_FAILED);
427 	}
428 	if (waitpid(pid, &status, 0) == -1) {
429 		warn("%s %s: waitpid", _PATH_RM, from);
430 		return (1);
431 	}
432 	if (!WIFEXITED(status)) {
433 		warnx("%s %s: did not terminate normally", _PATH_RM, from);
434 		return (1);
435 	}
436 	switch (WEXITSTATUS(status)) {
437 	case 0:
438 		break;
439 	case EXEC_FAILED:
440 		warnx("%s %s: exec failed", _PATH_RM, from);
441 		return (1);
442 	default:
443 		warnx("%s %s: terminated with %d (non-zero) status",
444 		    _PATH_RM, from, WEXITSTATUS(status));
445 		return (1);
446 	}
447 	return (0);
448 }
449 
450 static void
451 preserve_fd_acls(int source_fd, int dest_fd, const char *source_path,
452     const char *dest_path)
453 {
454 	acl_t acl;
455 	acl_type_t acl_type;
456 	int acl_supported = 0, ret, trivial;
457 
458 	ret = fpathconf(source_fd, _PC_ACL_NFS4);
459 	if (ret > 0 ) {
460 		acl_supported = 1;
461 		acl_type = ACL_TYPE_NFS4;
462 	} else if (ret < 0 && errno != EINVAL) {
463 		warn("fpathconf(..., _PC_ACL_NFS4) failed for %s",
464 		    source_path);
465 		return;
466 	}
467 	if (acl_supported == 0) {
468 		ret = fpathconf(source_fd, _PC_ACL_EXTENDED);
469 		if (ret > 0 ) {
470 			acl_supported = 1;
471 			acl_type = ACL_TYPE_ACCESS;
472 		} else if (ret < 0 && errno != EINVAL) {
473 			warn("fpathconf(..., _PC_ACL_EXTENDED) failed for %s",
474 			    source_path);
475 			return;
476 		}
477 	}
478 	if (acl_supported == 0)
479 		return;
480 
481 	acl = acl_get_fd_np(source_fd, acl_type);
482 	if (acl == NULL) {
483 		warn("failed to get acl entries for %s", source_path);
484 		return;
485 	}
486 	if (acl_is_trivial_np(acl, &trivial)) {
487 		warn("acl_is_trivial() failed for %s", source_path);
488 		acl_free(acl);
489 		return;
490 	}
491 	if (trivial) {
492 		acl_free(acl);
493 		return;
494 	}
495 	if (acl_set_fd_np(dest_fd, acl, acl_type) < 0) {
496 		warn("failed to set acl entries for %s", dest_path);
497 		acl_free(acl);
498 		return;
499 	}
500 	acl_free(acl);
501 }
502 
503 static void
504 usage(void)
505 {
506 
507 	(void)fprintf(stderr, "%s\n%s\n",
508 		      "usage: mv [-f | -i | -n] [-hv] source target",
509 		      "       mv [-f | -i | -n] [-v] source ... directory");
510 	exit(EX_USAGE);
511 }
512