xref: /dragonfly/bin/mv/mv.c (revision 335b9e93)
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 #ifdef SIGINFO
68 static void	siginfo(int);
69 #endif
70 
71 int
72 main(int argc, char *argv[])
73 {
74 	size_t baselen, len;
75 	int rval;
76 	char *p, *endp;
77 	struct stat sb;
78 	int ch;
79 	char path[PATH_MAX];
80 
81 	while ((ch = getopt(argc, argv, "fhinv")) != -1)
82 		switch (ch) {
83 		case 'h':
84 			hflg = 1;
85 			break;
86 		case 'i':
87 			iflg = 1;
88 			fflg = nflg = 0;
89 			break;
90 		case 'f':
91 			fflg = 1;
92 			iflg = nflg = 0;
93 			break;
94 		case 'n':
95 			nflg = 1;
96 			fflg = iflg = 0;
97 			break;
98 		case 'v':
99 			vflg = 1;
100 			break;
101 		default:
102 			usage();
103 		}
104 	argc -= optind;
105 	argv += optind;
106 
107 #ifdef SIGINFO
108 	signal(SIGINFO, siginfo);
109 #endif
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 	/*
125 	 * If -h was specified, treat the target as a symlink instead of
126 	 * directory.
127 	 */
128 	if (hflg) {
129 		if (argc > 2)
130 			usage();
131 		if (lstat(argv[1], &sb) == 0 && S_ISLNK(sb.st_mode))
132 			exit(do_move(argv[0], argv[1]));
133 	}
134 
135 	/* It's a directory, move each file into it. */
136 	if (strlen(argv[argc - 1]) > sizeof(path) - 1)
137 		errx(1, "%s: destination pathname too long", *argv);
138 	strcpy(path, argv[argc - 1]);
139 	baselen = strlen(path);
140 	endp = &path[baselen];
141 	if (!baselen || *(endp - 1) != '/') {
142 		*endp++ = '/';
143 		++baselen;
144 	}
145 	for (rval = 0; --argc; ++argv) {
146 		/*
147 		 * Find the last component of the source pathname.  It
148 		 * may have trailing slashes.
149 		 */
150 		p = *argv + strlen(*argv);
151 		while (p != *argv && p[-1] == '/')
152 			--p;
153 		while (p != *argv && p[-1] != '/')
154 			--p;
155 
156 		if ((baselen + (len = strlen(p))) >= PATH_MAX) {
157 			warnx("%s: destination pathname too long", *argv);
158 			rval = 1;
159 		} else {
160 			memmove(endp, p, (size_t)len + 1);
161 			if (do_move(*argv, path))
162 				rval = 1;
163 		}
164 	}
165 	exit(rval);
166 }
167 
168 static int
169 do_move(const char *from, const char *to)
170 {
171 	struct stat sb;
172 	int ask, ch, first;
173 	char modep[15];
174 
175 	/*
176 	 * Check access.  If interactive and file exists, ask user if it
177 	 * should be replaced.  Otherwise if file exists but isn't writable
178 	 * make sure the user wants to clobber it.
179 	 */
180 	if (!fflg && !access(to, F_OK)) {
181 
182 		/* prompt only if source exist */
183 		if (lstat(from, &sb) == -1) {
184 			warn("%s", from);
185 			return (1);
186 		}
187 
188 #define YESNO "(y/n [n]) "
189 		ask = 0;
190 		if (nflg) {
191 			if (vflg)
192 				printf("%s not overwritten\n", to);
193 			return (0);
194 		} else if (iflg) {
195 			fprintf(stderr, "overwrite %s? %s", to, YESNO);
196 			ask = 1;
197 		} else if (access(to, W_OK) && !stat(to, &sb) && isatty(STDIN_FILENO)) {
198 			strmode(sb.st_mode, modep);
199 			fprintf(stderr, "override %s%s%s/%s for %s? %s",
200 			    modep + 1, modep[9] == ' ' ? "" : " ",
201 			    user_from_uid((unsigned long)sb.st_uid, 0),
202 			    group_from_gid((unsigned long)sb.st_gid, 0), to, YESNO);
203 			ask = 1;
204 		}
205 		if (ask) {
206 			first = ch = getchar();
207 			while (ch != '\n' && ch != EOF)
208 				ch = getchar();
209 			if (first != 'y' && first != 'Y') {
210 				fprintf(stderr, "not overwritten\n");
211 				return (0);
212 			}
213 		}
214 	}
215 	/*
216 	 * Rename on FreeBSD will fail with EISDIR and ENOTDIR, before failing
217 	 * with EXDEV.  Therefore, copy() doesn't have to perform the checks
218 	 * specified in the Step 3 of the POSIX mv specification.
219 	 */
220 	if (!rename(from, to)) {
221 		if (vflg)
222 			printf("%s -> %s\n", from, to);
223 		return (0);
224 	}
225 
226 	if (errno == EXDEV) {
227 		char path[PATH_MAX];
228 		int target_is_file = 0;
229 
230 		if (!lstat(to, &sb) && S_ISREG(sb.st_mode))
231 			target_is_file = 1;
232 		/*
233 		 * If the source is a symbolic link and is on another
234 		 * filesystem, it can be recreated at the destination.
235 		 */
236 		if (lstat(from, &sb) == -1) {
237 			warn("%s", from);
238 			return (1);
239 		}
240 		/* Can't mv(1) directory into a file ever. */
241 		if (target_is_file && S_ISDIR(sb.st_mode)) {
242 			warn("cannot overwrite %s with directory", to);
243 			return (1);
244 		}
245 		if (!S_ISLNK(sb.st_mode)) {
246 			/* Can't mv(1) a mount point. */
247 			if (realpath(from, path) == NULL) {
248 				warn("cannot resolve %s: %s", from, path);
249 				return (1);
250 			}
251 #ifdef MNAMELEN
252 			struct statfs sfs;
253 			if (!statfs(path, &sfs) &&
254 			    !strcmp(path, sfs.f_mntonname)) {
255 				warnx("cannot rename a mount point");
256 				return (1);
257 			}
258 #endif
259 		}
260 	} else {
261 		warn("rename %s to %s", from, to);
262 		return (1);
263 	}
264 
265 	/*
266 	 * If rename fails because we're trying to cross devices, and
267 	 * it's a regular file, do the copy internally; otherwise, use
268 	 * cp and rm.
269 	 */
270 	if (lstat(from, &sb)) {
271 		warn("%s", from);
272 		return (1);
273 	}
274 	return (S_ISREG(sb.st_mode) ?
275 	    fastcopy(from, to, &sb) : copy(from, to));
276 }
277 
278 static int
279 fastcopy(const char *from, const char *to, struct stat *sbp)
280 {
281 	struct timeval tval[2];
282 	static u_int blen = MAXPHYS;
283 	static char *bp = NULL;
284 	mode_t oldmode;
285 	int from_fd, to_fd;
286 	ssize_t nread;
287 
288 	if ((from_fd = open(from, O_RDONLY, 0)) < 0) {
289 		warn("fastcopy: open() failed (from): %s", from);
290 		return (1);
291 	}
292 	if (bp == NULL && (bp = malloc((size_t)blen)) == NULL) {
293 		warnx("malloc(%u) failed", blen);
294 		return (1);
295 	}
296 	while ((to_fd =
297 	    open(to, O_CREAT | O_EXCL | O_TRUNC | O_WRONLY, 0)) < 0) {
298 		if (errno == EEXIST && unlink(to) == 0)
299 			continue;
300 		warn("fastcopy: open() failed (to): %s", to);
301 		close(from_fd);
302 		return (1);
303 	}
304 	while ((nread = read(from_fd, bp, (size_t)blen)) > 0)
305 		if (write(to_fd, bp, (size_t)nread) != nread) {
306 			warn("fastcopy: write() failed: %s", to);
307 			goto err;
308 		}
309 	if (nread < 0) {
310 		warn("fastcopy: read() failed: %s", from);
311 err:		if (unlink(to))
312 			warn("%s: remove", to);
313 		close(from_fd);
314 		close(to_fd);
315 		return (1);
316 	}
317 
318 	oldmode = sbp->st_mode & ALLPERMS;
319 	if (fchown(to_fd, sbp->st_uid, sbp->st_gid)) {
320 		warn("%s: set owner/group (was: %lu/%lu)", to,
321 		    (u_long)sbp->st_uid, (u_long)sbp->st_gid);
322 		if (oldmode & (S_ISUID | S_ISGID)) {
323 			warnx(
324 "%s: owner/group changed; clearing suid/sgid (mode was 0%03o)",
325 			    to, oldmode);
326 			sbp->st_mode &= ~(S_ISUID | S_ISGID);
327 		}
328 	}
329 	if (fchmod(to_fd, sbp->st_mode))
330 		warn("%s: set mode (was: 0%03o)", to, oldmode);
331 
332 	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 	errno = 0;
341 #ifdef _ST_FLAGS_PRESENT_
342 	if (fchflags(to_fd, sbp->st_flags))
343 		if (errno != EOPNOTSUPP || sbp->st_flags != 0)
344 			warn("%s: set flags (was: 0%07o)", to, sbp->st_flags);
345 #endif
346 
347 	tval[0].tv_sec = sbp->st_atime;
348 	tval[1].tv_sec = sbp->st_mtime;
349 	tval[0].tv_usec = tval[1].tv_usec = 0;
350 	if (utimes(to, tval))
351 		warn("%s: set times", to);
352 
353 	if (close(to_fd)) {
354 		warn("%s", to);
355 		return (1);
356 	}
357 
358 	if (unlink(from)) {
359 		warn("%s: remove", from);
360 		return (1);
361 	}
362 	if (vflg)
363 		printf("%s -> %s\n", from, to);
364 	return (0);
365 }
366 
367 static int
368 copy(const char *from, const char *to)
369 {
370 	struct stat sb;
371 	int status;
372 	pid_t pid;
373 
374 	if (lstat(to, &sb) == 0) {
375 		/* Destination path exists. */
376 		if (S_ISDIR(sb.st_mode)) {
377 			if (rmdir(to) != 0) {
378 				warn("rmdir %s", to);
379 				return (1);
380 			}
381 		} else {
382 			if (unlink(to) != 0) {
383 				warn("unlink %s", to);
384 				return (1);
385 			}
386 		}
387 	} else if (errno != ENOENT) {
388 		warn("%s", to);
389 		return (1);
390 	}
391 
392 	/* Copy source to destination. */
393 	if (!(pid = vfork())) {
394 		execl(_PATH_CP, "mv", vflg ? "-PRpv" : "-PRp", "--", from, to,
395 		    NULL);
396 		_exit(EXEC_FAILED);
397 	}
398 	if (waitpid(pid, &status, 0) == -1) {
399 		warn("%s %s %s: waitpid", _PATH_CP, from, to);
400 		return (1);
401 	}
402 	if (!WIFEXITED(status)) {
403 		warnx("%s %s %s: did not terminate normally",
404 		    _PATH_CP, from, to);
405 		return (1);
406 	}
407 	switch (WEXITSTATUS(status)) {
408 	case 0:
409 		break;
410 	case EXEC_FAILED:
411 		warnx("%s %s %s: exec failed", _PATH_CP, from, to);
412 		return (1);
413 	default:
414 		warnx("%s %s %s: terminated with %d (non-zero) status",
415 		    _PATH_CP, from, to, WEXITSTATUS(status));
416 		return (1);
417 	}
418 
419 	/* Delete the source. */
420 	if (!(pid = vfork())) {
421 		execl(_PATH_RM, "mv", "-rf", "--", from, NULL);
422 		_exit(EXEC_FAILED);
423 	}
424 	if (waitpid(pid, &status, 0) == -1) {
425 		warn("%s %s: waitpid", _PATH_RM, from);
426 		return (1);
427 	}
428 	if (!WIFEXITED(status)) {
429 		warnx("%s %s: did not terminate normally", _PATH_RM, from);
430 		return (1);
431 	}
432 	switch (WEXITSTATUS(status)) {
433 	case 0:
434 		break;
435 	case EXEC_FAILED:
436 		warnx("%s %s: exec failed", _PATH_RM, from);
437 		return (1);
438 	default:
439 		warnx("%s %s: terminated with %d (non-zero) status",
440 		    _PATH_RM, from, WEXITSTATUS(status));
441 		return (1);
442 	}
443 	return (0);
444 }
445 
446 static void
447 usage(void)
448 {
449 
450 	fprintf(stderr, "%s\n%s\n",
451 		"usage: mv [-f | -i | -n] [-hv] source target",
452 		"       mv [-f | -i | -n] [-v] source ... directory");
453 	exit(EX_USAGE);
454 }
455 
456 #ifdef SIGINFO
457 static void
458 siginfo(int notused __unused)
459 {
460 	info = 1;
461 }
462 #endif
463