xref: /freebsd/bin/mv/mv.c (revision 9a14aa017b21c292740c00ee098195cd46642730)
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, 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, "finv")) != -1)
91 		switch (ch) {
92 		case 'i':
93 			iflg = 1;
94 			fflg = nflg = 0;
95 			break;
96 		case 'f':
97 			fflg = 1;
98 			iflg = nflg = 0;
99 			break;
100 		case 'n':
101 			nflg = 1;
102 			fflg = iflg = 0;
103 			break;
104 		case 'v':
105 			vflg = 1;
106 			break;
107 		default:
108 			usage();
109 		}
110 	argc -= optind;
111 	argv += optind;
112 
113 	if (argc < 2)
114 		usage();
115 
116 	/*
117 	 * If the stat on the target fails or the target isn't a directory,
118 	 * try the move.  More than 2 arguments is an error in this case.
119 	 */
120 	if (stat(argv[argc - 1], &sb) || !S_ISDIR(sb.st_mode)) {
121 		if (argc > 2)
122 			usage();
123 		exit(do_move(argv[0], argv[1]));
124 	}
125 
126 	/* It's a directory, move each file into it. */
127 	if (strlen(argv[argc - 1]) > sizeof(path) - 1)
128 		errx(1, "%s: destination pathname too long", *argv);
129 	(void)strcpy(path, argv[argc - 1]);
130 	baselen = strlen(path);
131 	endp = &path[baselen];
132 	if (!baselen || *(endp - 1) != '/') {
133 		*endp++ = '/';
134 		++baselen;
135 	}
136 	for (rval = 0; --argc; ++argv) {
137 		/*
138 		 * Find the last component of the source pathname.  It
139 		 * may have trailing slashes.
140 		 */
141 		p = *argv + strlen(*argv);
142 		while (p != *argv && p[-1] == '/')
143 			--p;
144 		while (p != *argv && p[-1] != '/')
145 			--p;
146 
147 		if ((baselen + (len = strlen(p))) >= PATH_MAX) {
148 			warnx("%s: destination pathname too long", *argv);
149 			rval = 1;
150 		} else {
151 			memmove(endp, p, (size_t)len + 1);
152 			if (do_move(*argv, path))
153 				rval = 1;
154 		}
155 	}
156 	exit(rval);
157 }
158 
159 static int
160 do_move(const char *from, const char *to)
161 {
162 	struct stat sb;
163 	int ask, ch, first;
164 	char modep[15];
165 
166 	/*
167 	 * Check access.  If interactive and file exists, ask user if it
168 	 * should be replaced.  Otherwise if file exists but isn't writable
169 	 * make sure the user wants to clobber it.
170 	 */
171 	if (!fflg && !access(to, F_OK)) {
172 
173 		/* prompt only if source exist */
174 	        if (lstat(from, &sb) == -1) {
175 			warn("%s", from);
176 			return (1);
177 		}
178 
179 #define YESNO "(y/n [n]) "
180 		ask = 0;
181 		if (nflg) {
182 			if (vflg)
183 				printf("%s not overwritten\n", to);
184 			return (0);
185 		} else if (iflg) {
186 			(void)fprintf(stderr, "overwrite %s? %s", to, YESNO);
187 			ask = 1;
188 		} else if (access(to, W_OK) && !stat(to, &sb)) {
189 			strmode(sb.st_mode, modep);
190 			(void)fprintf(stderr, "override %s%s%s/%s for %s? %s",
191 			    modep + 1, modep[9] == ' ' ? "" : " ",
192 			    user_from_uid((unsigned long)sb.st_uid, 0),
193 			    group_from_gid((unsigned long)sb.st_gid, 0), to, YESNO);
194 			ask = 1;
195 		}
196 		if (ask) {
197 			first = ch = getchar();
198 			while (ch != '\n' && ch != EOF)
199 				ch = getchar();
200 			if (first != 'y' && first != 'Y') {
201 				(void)fprintf(stderr, "not overwritten\n");
202 				return (0);
203 			}
204 		}
205 	}
206 	/*
207 	 * Rename on FreeBSD will fail with EISDIR and ENOTDIR, before failing
208 	 * with EXDEV.  Therefore, copy() doesn't have to perform the checks
209 	 * specified in the Step 3 of the POSIX mv specification.
210 	 */
211 	if (!rename(from, to)) {
212 		if (vflg)
213 			printf("%s -> %s\n", from, to);
214 		return (0);
215 	}
216 
217 	if (errno == EXDEV) {
218 		struct statfs sfs;
219 		char path[PATH_MAX];
220 
221 		/*
222 		 * If the source is a symbolic link and is on another
223 		 * filesystem, it can be recreated at the destination.
224 		 */
225 		if (lstat(from, &sb) == -1) {
226 			warn("%s", from);
227 			return (1);
228 		}
229 		if (!S_ISLNK(sb.st_mode)) {
230 			/* Can't mv(1) a mount point. */
231 			if (realpath(from, path) == NULL) {
232 				warn("cannot resolve %s: %s", from, path);
233 				return (1);
234 			}
235 			if (!statfs(path, &sfs) &&
236 			    !strcmp(path, sfs.f_mntonname)) {
237 				warnx("cannot rename a mount point");
238 				return (1);
239 			}
240 		}
241 	} else {
242 		warn("rename %s to %s", from, to);
243 		return (1);
244 	}
245 
246 	/*
247 	 * If rename fails because we're trying to cross devices, and
248 	 * it's a regular file, do the copy internally; otherwise, use
249 	 * cp and rm.
250 	 */
251 	if (lstat(from, &sb)) {
252 		warn("%s", from);
253 		return (1);
254 	}
255 	return (S_ISREG(sb.st_mode) ?
256 	    fastcopy(from, to, &sb) : copy(from, to));
257 }
258 
259 static int
260 fastcopy(const char *from, const char *to, struct stat *sbp)
261 {
262 	struct timeval tval[2];
263 	static u_int blen = MAXPHYS;
264 	static char *bp = NULL;
265 	mode_t oldmode;
266 	int nread, from_fd, to_fd;
267 
268 	if ((from_fd = open(from, O_RDONLY, 0)) < 0) {
269 		warn("fastcopy: open() failed (from): %s", from);
270 		return (1);
271 	}
272 	if (bp == NULL && (bp = malloc((size_t)blen)) == NULL) {
273 		warnx("malloc(%u) failed", blen);
274 		return (1);
275 	}
276 	while ((to_fd =
277 	    open(to, O_CREAT | O_EXCL | O_TRUNC | O_WRONLY, 0)) < 0) {
278 		if (errno == EEXIST && unlink(to) == 0)
279 			continue;
280 		warn("fastcopy: open() failed (to): %s", to);
281 		(void)close(from_fd);
282 		return (1);
283 	}
284 	while ((nread = read(from_fd, bp, (size_t)blen)) > 0)
285 		if (write(to_fd, bp, (size_t)nread) != nread) {
286 			warn("fastcopy: write() failed: %s", to);
287 			goto err;
288 		}
289 	if (nread < 0) {
290 		warn("fastcopy: read() failed: %s", from);
291 err:		if (unlink(to))
292 			warn("%s: remove", to);
293 		(void)close(from_fd);
294 		(void)close(to_fd);
295 		return (1);
296 	}
297 
298 	oldmode = sbp->st_mode & ALLPERMS;
299 	if (fchown(to_fd, sbp->st_uid, sbp->st_gid)) {
300 		warn("%s: set owner/group (was: %lu/%lu)", to,
301 		    (u_long)sbp->st_uid, (u_long)sbp->st_gid);
302 		if (oldmode & (S_ISUID | S_ISGID)) {
303 			warnx(
304 "%s: owner/group changed; clearing suid/sgid (mode was 0%03o)",
305 			    to, oldmode);
306 			sbp->st_mode &= ~(S_ISUID | S_ISGID);
307 		}
308 	}
309 	if (fchmod(to_fd, sbp->st_mode))
310 		warn("%s: set mode (was: 0%03o)", to, oldmode);
311 	/*
312 	 * POSIX 1003.2c states that if _POSIX_ACL_EXTENDED is in effect
313 	 * for dest_file, then its ACLs shall reflect the ACLs of the
314 	 * source_file.
315 	 */
316 	preserve_fd_acls(from_fd, to_fd, from, to);
317 	(void)close(from_fd);
318 	/*
319 	 * XXX
320 	 * NFS doesn't support chflags; ignore errors unless there's reason
321 	 * to believe we're losing bits.  (Note, this still won't be right
322 	 * if the server supports flags and we were trying to *remove* flags
323 	 * on a file that we copied, i.e., that we didn't create.)
324 	 */
325 	errno = 0;
326 	if (fchflags(to_fd, (u_long)sbp->st_flags))
327 		if (errno != EOPNOTSUPP || sbp->st_flags != 0)
328 			warn("%s: set flags (was: 0%07o)", to, sbp->st_flags);
329 
330 	tval[0].tv_sec = sbp->st_atime;
331 	tval[1].tv_sec = sbp->st_mtime;
332 	tval[0].tv_usec = tval[1].tv_usec = 0;
333 	if (utimes(to, tval))
334 		warn("%s: set times", to);
335 
336 	if (close(to_fd)) {
337 		warn("%s", to);
338 		return (1);
339 	}
340 
341 	if (unlink(from)) {
342 		warn("%s: remove", from);
343 		return (1);
344 	}
345 	if (vflg)
346 		printf("%s -> %s\n", from, to);
347 	return (0);
348 }
349 
350 static int
351 copy(const char *from, const char *to)
352 {
353 	struct stat sb;
354 	int pid, status;
355 
356 	if (lstat(to, &sb) == 0) {
357 		/* Destination path exists. */
358 		if (S_ISDIR(sb.st_mode)) {
359 			if (rmdir(to) != 0) {
360 				warn("rmdir %s", to);
361 				return (1);
362 			}
363 		} else {
364 			if (unlink(to) != 0) {
365 				warn("unlink %s", to);
366 				return (1);
367 			}
368 		}
369 	} else if (errno != ENOENT) {
370 		warn("%s", to);
371 		return (1);
372 	}
373 
374 	/* Copy source to destination. */
375 	if (!(pid = vfork())) {
376 		execl(_PATH_CP, "mv", vflg ? "-PRpv" : "-PRp", "--", from, to,
377 		    (char *)NULL);
378 		_exit(EXEC_FAILED);
379 	}
380 	if (waitpid(pid, &status, 0) == -1) {
381 		warn("%s %s %s: waitpid", _PATH_CP, from, to);
382 		return (1);
383 	}
384 	if (!WIFEXITED(status)) {
385 		warnx("%s %s %s: did not terminate normally",
386 		    _PATH_CP, from, to);
387 		return (1);
388 	}
389 	switch (WEXITSTATUS(status)) {
390 	case 0:
391 		break;
392 	case EXEC_FAILED:
393 		warnx("%s %s %s: exec failed", _PATH_CP, from, to);
394 		return (1);
395 	default:
396 		warnx("%s %s %s: terminated with %d (non-zero) status",
397 		    _PATH_CP, from, to, WEXITSTATUS(status));
398 		return (1);
399 	}
400 
401 	/* Delete the source. */
402 	if (!(pid = vfork())) {
403 		execl(_PATH_RM, "mv", "-rf", "--", from, (char *)NULL);
404 		_exit(EXEC_FAILED);
405 	}
406 	if (waitpid(pid, &status, 0) == -1) {
407 		warn("%s %s: waitpid", _PATH_RM, from);
408 		return (1);
409 	}
410 	if (!WIFEXITED(status)) {
411 		warnx("%s %s: did not terminate normally", _PATH_RM, from);
412 		return (1);
413 	}
414 	switch (WEXITSTATUS(status)) {
415 	case 0:
416 		break;
417 	case EXEC_FAILED:
418 		warnx("%s %s: exec failed", _PATH_RM, from);
419 		return (1);
420 	default:
421 		warnx("%s %s: terminated with %d (non-zero) status",
422 		    _PATH_RM, from, WEXITSTATUS(status));
423 		return (1);
424 	}
425 	return (0);
426 }
427 
428 static void
429 preserve_fd_acls(int source_fd, int dest_fd, const char *source_path,
430     const char *dest_path)
431 {
432 	acl_t acl;
433 	acl_type_t acl_type;
434 	int acl_supported = 0, ret, trivial;
435 
436 	ret = fpathconf(source_fd, _PC_ACL_NFS4);
437 	if (ret > 0 ) {
438 		acl_supported = 1;
439 		acl_type = ACL_TYPE_NFS4;
440 	} else if (ret < 0 && errno != EINVAL) {
441 		warn("fpathconf(..., _PC_ACL_NFS4) failed for %s",
442 		    source_path);
443 		return;
444 	}
445 	if (acl_supported == 0) {
446 		ret = fpathconf(source_fd, _PC_ACL_EXTENDED);
447 		if (ret > 0 ) {
448 			acl_supported = 1;
449 			acl_type = ACL_TYPE_ACCESS;
450 		} else if (ret < 0 && errno != EINVAL) {
451 			warn("fpathconf(..., _PC_ACL_EXTENDED) failed for %s",
452 			    source_path);
453 			return;
454 		}
455 	}
456 	if (acl_supported == 0)
457 		return;
458 
459 	acl = acl_get_fd_np(source_fd, acl_type);
460 	if (acl == NULL) {
461 		warn("failed to get acl entries for %s", source_path);
462 		return;
463 	}
464 	if (acl_is_trivial_np(acl, &trivial)) {
465 		warn("acl_is_trivial() failed for %s", source_path);
466 		acl_free(acl);
467 		return;
468 	}
469 	if (trivial) {
470 		acl_free(acl);
471 		return;
472 	}
473 	if (acl_set_fd_np(dest_fd, acl, acl_type) < 0) {
474 		warn("failed to set acl entries for %s", dest_path);
475 		acl_free(acl);
476 		return;
477 	}
478 	acl_free(acl);
479 }
480 
481 static void
482 usage(void)
483 {
484 
485 	(void)fprintf(stderr, "%s\n%s\n",
486 		      "usage: mv [-f | -i | -n] [-v] source target",
487 		      "       mv [-f | -i | -n] [-v] source ... directory");
488 	exit(EX_USAGE);
489 }
490