mv.c revision 280386
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
35static 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
41static char sccsid[] = "@(#)mv.c	8.2 (Berkeley) 4/2/94";
42#endif /* not lint */
43#endif
44#include <sys/cdefs.h>
45__FBSDID("$FreeBSD: head/bin/mv/mv.c 280386 2015-03-23 17:35:05Z jilles $");
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
71static int	fflg, hflg, iflg, nflg, vflg;
72
73static int	copy(const char *, const char *);
74static int	do_move(const char *, const char *);
75static int	fastcopy(const char *, const char *, struct stat *);
76static void	usage(void);
77static void	preserve_fd_acls(int source_fd, int dest_fd, const char *source_path,
78		    const char *dest_path);
79
80int
81main(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			usage();
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
173static int
174do_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
273static int
274fastcopy(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);
306err:		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
372static int
373copy(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
450static void
451preserve_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
503static void
504usage(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