xref: /freebsd/bin/mv/mv.c (revision 1669d8afc64812c8d2d1d147ae1fd42ff441e1b1)
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 int fflg, iflg, nflg, vflg;
72 
73 int	copy(char *, char *);
74 int	do_move(char *, char *);
75 int	fastcopy(char *, char *, struct stat *);
76 void	usage(void);
77 
78 int
79 main(int argc, char *argv[])
80 {
81 	size_t baselen, len;
82 	int rval;
83 	char *p, *endp;
84 	struct stat sb;
85 	int ch;
86 	char path[PATH_MAX];
87 
88 	while ((ch = getopt(argc, argv, "finv")) != -1)
89 		switch (ch) {
90 		case 'i':
91 			iflg = 1;
92 			fflg = nflg = 0;
93 			break;
94 		case 'f':
95 			fflg = 1;
96 			iflg = nflg = 0;
97 			break;
98 		case 'n':
99 			nflg = 1;
100 			fflg = iflg = 0;
101 			break;
102 		case 'v':
103 			vflg = 1;
104 			break;
105 		default:
106 			usage();
107 		}
108 	argc -= optind;
109 	argv += optind;
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 	/* It's a directory, move each file into it. */
125 	if (strlen(argv[argc - 1]) > sizeof(path) - 1)
126 		errx(1, "%s: destination pathname too long", *argv);
127 	(void)strcpy(path, argv[argc - 1]);
128 	baselen = strlen(path);
129 	endp = &path[baselen];
130 	if (!baselen || *(endp - 1) != '/') {
131 		*endp++ = '/';
132 		++baselen;
133 	}
134 	for (rval = 0; --argc; ++argv) {
135 		/*
136 		 * Find the last component of the source pathname.  It
137 		 * may have trailing slashes.
138 		 */
139 		p = *argv + strlen(*argv);
140 		while (p != *argv && p[-1] == '/')
141 			--p;
142 		while (p != *argv && p[-1] != '/')
143 			--p;
144 
145 		if ((baselen + (len = strlen(p))) >= PATH_MAX) {
146 			warnx("%s: destination pathname too long", *argv);
147 			rval = 1;
148 		} else {
149 			memmove(endp, p, (size_t)len + 1);
150 			if (do_move(*argv, path))
151 				rval = 1;
152 		}
153 	}
154 	exit(rval);
155 }
156 
157 int
158 do_move(char *from, char *to)
159 {
160 	struct stat sb;
161 	int ask, ch, first;
162 	char modep[15];
163 
164 	/*
165 	 * Check access.  If interactive and file exists, ask user if it
166 	 * should be replaced.  Otherwise if file exists but isn't writable
167 	 * make sure the user wants to clobber it.
168 	 */
169 	if (!fflg && !access(to, F_OK)) {
170 
171 		/* prompt only if source exist */
172 	        if (lstat(from, &sb) == -1) {
173 			warn("%s", from);
174 			return (1);
175 		}
176 
177 #define YESNO "(y/n [n]) "
178 		ask = 0;
179 		if (nflg) {
180 			if (vflg)
181 				printf("%s not overwritten\n", to);
182 			return (0);
183 		} else if (iflg) {
184 			(void)fprintf(stderr, "overwrite %s? %s", to, YESNO);
185 			ask = 1;
186 		} else if (access(to, W_OK) && !stat(to, &sb)) {
187 			strmode(sb.st_mode, modep);
188 			(void)fprintf(stderr, "override %s%s%s/%s for %s? %s",
189 			    modep + 1, modep[9] == ' ' ? "" : " ",
190 			    user_from_uid((unsigned long)sb.st_uid, 0),
191 			    group_from_gid((unsigned long)sb.st_gid, 0), to, YESNO);
192 			ask = 1;
193 		}
194 		if (ask) {
195 			first = ch = getchar();
196 			while (ch != '\n' && ch != EOF)
197 				ch = getchar();
198 			if (first != 'y' && first != 'Y') {
199 				(void)fprintf(stderr, "not overwritten\n");
200 				return (0);
201 			}
202 		}
203 	}
204 	/*
205 	 * Rename on FreeBSD will fail with EISDIR and ENOTDIR, before failing
206 	 * with EXDEV.  Therefore, copy() doesn't have to perform the checks
207 	 * specified in the Step 3 of the POSIX mv specification.
208 	 */
209 	if (!rename(from, to)) {
210 		if (vflg)
211 			printf("%s -> %s\n", from, to);
212 		return (0);
213 	}
214 
215 	if (errno == EXDEV) {
216 		struct statfs sfs;
217 		char path[PATH_MAX];
218 
219 		/*
220 		 * If the source is a symbolic link and is on another
221 		 * filesystem, it can be recreated at the destination.
222 		 */
223 		if (lstat(from, &sb) == -1) {
224 			warn("%s", from);
225 			return (1);
226 		}
227 		if (!S_ISLNK(sb.st_mode)) {
228 			/* Can't mv(1) a mount point. */
229 			if (realpath(from, path) == NULL) {
230 				warn("cannot resolve %s: %s", from, path);
231 				return (1);
232 			}
233 			if (!statfs(path, &sfs) &&
234 			    !strcmp(path, sfs.f_mntonname)) {
235 				warnx("cannot rename a mount point");
236 				return (1);
237 			}
238 		}
239 	} else {
240 		warn("rename %s to %s", from, to);
241 		return (1);
242 	}
243 
244 	/*
245 	 * If rename fails because we're trying to cross devices, and
246 	 * it's a regular file, do the copy internally; otherwise, use
247 	 * cp and rm.
248 	 */
249 	if (lstat(from, &sb)) {
250 		warn("%s", from);
251 		return (1);
252 	}
253 	return (S_ISREG(sb.st_mode) ?
254 	    fastcopy(from, to, &sb) : copy(from, to));
255 }
256 
257 int
258 fastcopy(char *from, char *to, struct stat *sbp)
259 {
260 	struct timeval tval[2];
261 	static u_int blen;
262 	static char *bp;
263 	acl_t acl;
264 	mode_t oldmode;
265 	int nread, from_fd, to_fd;
266 
267 	if ((from_fd = open(from, O_RDONLY, 0)) < 0) {
268 		warn("%s", from);
269 		return (1);
270 	}
271 	if (blen < sbp->st_blksize) {
272 		if (bp != NULL)
273 			free(bp);
274 		if ((bp = malloc((size_t)sbp->st_blksize)) == NULL) {
275 			blen = 0;
276 			warnx("malloc failed");
277 			return (1);
278 		}
279 		blen = sbp->st_blksize;
280 	}
281 	while ((to_fd =
282 	    open(to, O_CREAT | O_EXCL | O_TRUNC | O_WRONLY, 0)) < 0) {
283 		if (errno == EEXIST && unlink(to) == 0)
284 			continue;
285 		warn("%s", to);
286 		(void)close(from_fd);
287 		return (1);
288 	}
289 	while ((nread = read(from_fd, bp, (size_t)blen)) > 0)
290 		if (write(to_fd, bp, (size_t)nread) != nread) {
291 			warn("%s", to);
292 			goto err;
293 		}
294 	if (nread < 0) {
295 		warn("%s", from);
296 err:		if (unlink(to))
297 			warn("%s: remove", to);
298 		(void)close(from_fd);
299 		(void)close(to_fd);
300 		return (1);
301 	}
302 
303 	oldmode = sbp->st_mode & ALLPERMS;
304 	if (fchown(to_fd, sbp->st_uid, sbp->st_gid)) {
305 		warn("%s: set owner/group (was: %lu/%lu)", to,
306 		    (u_long)sbp->st_uid, (u_long)sbp->st_gid);
307 		if (oldmode & (S_ISUID | S_ISGID)) {
308 			warnx(
309 "%s: owner/group changed; clearing suid/sgid (mode was 0%03o)",
310 			    to, oldmode);
311 			sbp->st_mode &= ~(S_ISUID | S_ISGID);
312 		}
313 	}
314 	/*
315 	 * POSIX 1003.2c states that if _POSIX_ACL_EXTENDED is in effect
316 	 * for dest_file, then its ACLs shall reflect the ACLs of the
317 	 * source_file.
318 	 */
319 	if (fpathconf(to_fd, _PC_ACL_EXTENDED) == 1 &&
320 	    fpathconf(from_fd, _PC_ACL_EXTENDED) == 1) {
321 		acl = acl_get_fd(from_fd);
322 		if (acl == NULL)
323 			warn("failed to get acl entries while setting %s",
324 			    from);
325 		else if (acl_set_fd(to_fd, acl) < 0)
326 			warn("failed to set acl entries for %s", to);
327 	}
328 	(void)close(from_fd);
329 	if (fchmod(to_fd, sbp->st_mode))
330 		warn("%s: set mode (was: 0%03o)", to, oldmode);
331 	/*
332 	 * XXX
333 	 * NFS doesn't support chflags; ignore errors unless there's reason
334 	 * to believe we're losing bits.  (Note, this still won't be right
335 	 * if the server supports flags and we were trying to *remove* flags
336 	 * on a file that we copied, i.e., that we didn't create.)
337 	 */
338 	errno = 0;
339 	if (fchflags(to_fd, (u_long)sbp->st_flags))
340 		if (errno != EOPNOTSUPP || sbp->st_flags != 0)
341 			warn("%s: set flags (was: 0%07o)", to, sbp->st_flags);
342 
343 	tval[0].tv_sec = sbp->st_atime;
344 	tval[1].tv_sec = sbp->st_mtime;
345 	tval[0].tv_usec = tval[1].tv_usec = 0;
346 	if (utimes(to, tval))
347 		warn("%s: set times", to);
348 
349 	if (close(to_fd)) {
350 		warn("%s", to);
351 		return (1);
352 	}
353 
354 	if (unlink(from)) {
355 		warn("%s: remove", from);
356 		return (1);
357 	}
358 	if (vflg)
359 		printf("%s -> %s\n", from, to);
360 	return (0);
361 }
362 
363 int
364 copy(char *from, char *to)
365 {
366 	struct stat sb;
367 	int pid, status;
368 
369 	if (lstat(to, &sb) == 0) {
370 		/* Destination path exists. */
371 		if (S_ISDIR(sb.st_mode)) {
372 			if (rmdir(to) != 0) {
373 				warn("rmdir %s", to);
374 				return (1);
375 			}
376 		} else {
377 			if (unlink(to) != 0) {
378 				warn("unlink %s", to);
379 				return (1);
380 			}
381 		}
382 	} else if (errno != ENOENT) {
383 		warn("%s", to);
384 		return (1);
385 	}
386 
387 	/* Copy source to destination. */
388 	if (!(pid = vfork())) {
389 		execl(_PATH_CP, "mv", vflg ? "-PRpv" : "-PRp", "--", from, to,
390 		    (char *)NULL);
391 		_exit(EXEC_FAILED);
392 	}
393 	if (waitpid(pid, &status, 0) == -1) {
394 		warn("%s %s %s: waitpid", _PATH_CP, from, to);
395 		return (1);
396 	}
397 	if (!WIFEXITED(status)) {
398 		warnx("%s %s %s: did not terminate normally",
399 		    _PATH_CP, from, to);
400 		return (1);
401 	}
402 	switch (WEXITSTATUS(status)) {
403 	case 0:
404 		break;
405 	case EXEC_FAILED:
406 		warnx("%s %s %s: exec failed", _PATH_CP, from, to);
407 		return (1);
408 	default:
409 		warnx("%s %s %s: terminated with %d (non-zero) status",
410 		    _PATH_CP, from, to, WEXITSTATUS(status));
411 		return (1);
412 	}
413 
414 	/* Delete the source. */
415 	if (!(pid = vfork())) {
416 		execl(_PATH_RM, "mv", "-rf", "--", from, (char *)NULL);
417 		_exit(EXEC_FAILED);
418 	}
419 	if (waitpid(pid, &status, 0) == -1) {
420 		warn("%s %s: waitpid", _PATH_RM, from);
421 		return (1);
422 	}
423 	if (!WIFEXITED(status)) {
424 		warnx("%s %s: did not terminate normally", _PATH_RM, from);
425 		return (1);
426 	}
427 	switch (WEXITSTATUS(status)) {
428 	case 0:
429 		break;
430 	case EXEC_FAILED:
431 		warnx("%s %s: exec failed", _PATH_RM, from);
432 		return (1);
433 	default:
434 		warnx("%s %s: terminated with %d (non-zero) status",
435 		    _PATH_RM, from, WEXITSTATUS(status));
436 		return (1);
437 	}
438 	return (0);
439 }
440 
441 void
442 usage(void)
443 {
444 
445 	(void)fprintf(stderr, "%s\n%s\n",
446 		      "usage: mv [-f | -i | -n] [-v] source target",
447 		      "       mv [-f | -i | -n] [-v] source ... directory");
448 	exit(EX_USAGE);
449 }
450