xref: /freebsd/usr.bin/xinstall/xinstall.c (revision 4f29da19bd44f0e99f021510460a81bf754c21d2)
1 /*
2  * Copyright (c) 1987, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 static const char copyright[] =
36 "@(#) Copyright (c) 1987, 1993\n\
37 	The Regents of the University of California.  All rights reserved.\n";
38 #endif /* not lint */
39 
40 #if 0
41 #ifndef lint
42 static char sccsid[] = "@(#)xinstall.c	8.1 (Berkeley) 7/21/93";
43 #endif /* not lint */
44 #endif
45 
46 #include <sys/cdefs.h>
47 __FBSDID("$FreeBSD$");
48 
49 #include <sys/param.h>
50 #include <sys/mman.h>
51 #include <sys/mount.h>
52 #include <sys/stat.h>
53 #include <sys/time.h>
54 #include <sys/wait.h>
55 
56 #include <ctype.h>
57 #include <err.h>
58 #include <errno.h>
59 #include <fcntl.h>
60 #include <grp.h>
61 #include <paths.h>
62 #include <pwd.h>
63 #include <stdio.h>
64 #include <stdlib.h>
65 #include <string.h>
66 #include <sysexits.h>
67 #include <unistd.h>
68 
69 /* Bootstrap aid - this doesn't exist in most older releases */
70 #ifndef MAP_FAILED
71 #define MAP_FAILED ((void *)-1)	/* from <sys/mman.h> */
72 #endif
73 
74 #define MAX_CMP_SIZE	(16 * 1024 * 1024)
75 
76 #define	DIRECTORY	0x01		/* Tell install it's a directory. */
77 #define	SETFLAGS	0x02		/* Tell install to set flags. */
78 #define	NOCHANGEBITS	(UF_IMMUTABLE | UF_APPEND | SF_IMMUTABLE | SF_APPEND)
79 #define	BACKUP_SUFFIX	".old"
80 
81 struct passwd *pp;
82 struct group *gp;
83 gid_t gid;
84 uid_t uid;
85 int dobackup, docompare, dodir, dopreserve, dostrip, nommap, safecopy, verbose;
86 mode_t mode = S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH;
87 const char *suffix = BACKUP_SUFFIX;
88 
89 void	copy(int, const char *, int, const char *, off_t);
90 int	compare(int, const char *, size_t, int, const char *, size_t);
91 int	create_newfile(const char *, int, struct stat *);
92 int	create_tempfile(const char *, char *, size_t);
93 void	install(const char *, const char *, u_long, u_int);
94 void	install_dir(char *);
95 u_long	numeric_id(const char *, const char *);
96 void	strip(const char *);
97 int	trymmap(int);
98 void	usage(void);
99 
100 int
101 main(int argc, char *argv[])
102 {
103 	struct stat from_sb, to_sb;
104 	mode_t *set;
105 	u_long fset;
106 	int ch, no_target;
107 	u_int iflags;
108 	char *flags;
109 	const char *group, *owner, *to_name;
110 
111 	iflags = 0;
112 	group = owner = NULL;
113 	while ((ch = getopt(argc, argv, "B:bCcdf:g:Mm:o:pSsv")) != -1)
114 		switch((char)ch) {
115 		case 'B':
116 			suffix = optarg;
117 			/* FALLTHROUGH */
118 		case 'b':
119 			dobackup = 1;
120 			break;
121 		case 'C':
122 			docompare = 1;
123 			break;
124 		case 'c':
125 			/* For backwards compatibility. */
126 			break;
127 		case 'd':
128 			dodir = 1;
129 			break;
130 		case 'f':
131 			flags = optarg;
132 			if (strtofflags(&flags, &fset, NULL))
133 				errx(EX_USAGE, "%s: invalid flag", flags);
134 			iflags |= SETFLAGS;
135 			break;
136 		case 'g':
137 			group = optarg;
138 			break;
139 		case 'M':
140 			nommap = 1;
141 			break;
142 		case 'm':
143 			if (!(set = setmode(optarg)))
144 				errx(EX_USAGE, "invalid file mode: %s",
145 				     optarg);
146 			mode = getmode(set, 0);
147 			free(set);
148 			break;
149 		case 'o':
150 			owner = optarg;
151 			break;
152 		case 'p':
153 			docompare = dopreserve = 1;
154 			break;
155 		case 'S':
156 			safecopy = 1;
157 			break;
158 		case 's':
159 			dostrip = 1;
160 			break;
161 		case 'v':
162 			verbose = 1;
163 			break;
164 		case '?':
165 		default:
166 			usage();
167 		}
168 	argc -= optind;
169 	argv += optind;
170 
171 	/* some options make no sense when creating directories */
172 	if (dostrip && dodir) {
173 		warnx("-d and -s may not be specified together");
174 		usage();
175 	}
176 
177 	if (getenv("DONTSTRIP") != NULL) {
178 		warnx("DONTSTRIP set - will not strip installed binaries");
179 		dostrip = 0;
180 	}
181 
182 	/* must have at least two arguments, except when creating directories */
183 	if (argc == 0 || (argc == 1 && !dodir))
184 		usage();
185 
186 	/* need to make a temp copy so we can compare stripped version */
187 	if (docompare && dostrip)
188 		safecopy = 1;
189 
190 	/* get group and owner id's */
191 	if (group != NULL) {
192 		if ((gp = getgrnam(group)) != NULL)
193 			gid = gp->gr_gid;
194 		else
195 			gid = (gid_t)numeric_id(group, "group");
196 	} else
197 		gid = (gid_t)-1;
198 
199 	if (owner != NULL) {
200 		if ((pp = getpwnam(owner)) != NULL)
201 			uid = pp->pw_uid;
202 		else
203 			uid = (uid_t)numeric_id(owner, "user");
204 	} else
205 		uid = (uid_t)-1;
206 
207 	if (dodir) {
208 		for (; *argv != NULL; ++argv)
209 			install_dir(*argv);
210 		exit(EX_OK);
211 		/* NOTREACHED */
212 	}
213 
214 	no_target = stat(to_name = argv[argc - 1], &to_sb);
215 	if (!no_target && S_ISDIR(to_sb.st_mode)) {
216 		for (; *argv != to_name; ++argv)
217 			install(*argv, to_name, fset, iflags | DIRECTORY);
218 		exit(EX_OK);
219 		/* NOTREACHED */
220 	}
221 
222 	/* can't do file1 file2 directory/file */
223 	if (argc != 2) {
224 		warnx("wrong number or types of arguments");
225 		usage();
226 	}
227 
228 	if (!no_target) {
229 		if (stat(*argv, &from_sb))
230 			err(EX_OSERR, "%s", *argv);
231 		if (!S_ISREG(to_sb.st_mode)) {
232 			errno = EFTYPE;
233 			err(EX_OSERR, "%s", to_name);
234 		}
235 		if (to_sb.st_dev == from_sb.st_dev &&
236 		    to_sb.st_ino == from_sb.st_ino)
237 			errx(EX_USAGE,
238 			    "%s and %s are the same file", *argv, to_name);
239 	}
240 	install(*argv, to_name, fset, iflags);
241 	exit(EX_OK);
242 	/* NOTREACHED */
243 }
244 
245 u_long
246 numeric_id(const char *name, const char *type)
247 {
248 	u_long val;
249 	char *ep;
250 
251 	/*
252 	 * XXX
253 	 * We know that uid_t's and gid_t's are unsigned longs.
254 	 */
255 	errno = 0;
256 	val = strtoul(name, &ep, 10);
257 	if (errno)
258 		err(EX_NOUSER, "%s", name);
259 	if (*ep != '\0')
260 		errx(EX_NOUSER, "unknown %s %s", type, name);
261 	return (val);
262 }
263 
264 /*
265  * install --
266  *	build a path name and install the file
267  */
268 void
269 install(const char *from_name, const char *to_name, u_long fset, u_int flags)
270 {
271 	struct stat from_sb, temp_sb, to_sb;
272 	struct timeval tvb[2];
273 	int devnull, files_match, from_fd, serrno, target;
274 	int tempcopy, temp_fd, to_fd;
275 	char backup[MAXPATHLEN], *p, pathbuf[MAXPATHLEN], tempfile[MAXPATHLEN];
276 
277 	files_match = 0;
278 	from_fd = -1;
279 	to_fd = -1;
280 
281 	/* If try to install NULL file to a directory, fails. */
282 	if (flags & DIRECTORY || strcmp(from_name, _PATH_DEVNULL)) {
283 		if (stat(from_name, &from_sb))
284 			err(EX_OSERR, "%s", from_name);
285 		if (!S_ISREG(from_sb.st_mode)) {
286 			errno = EFTYPE;
287 			err(EX_OSERR, "%s", from_name);
288 		}
289 		/* Build the target path. */
290 		if (flags & DIRECTORY) {
291 			(void)snprintf(pathbuf, sizeof(pathbuf), "%s/%s",
292 			    to_name,
293 			    (p = strrchr(from_name, '/')) ? ++p : from_name);
294 			to_name = pathbuf;
295 		}
296 		devnull = 0;
297 	} else {
298 		devnull = 1;
299 	}
300 
301 	target = stat(to_name, &to_sb) == 0;
302 
303 	/* Only install to regular files. */
304 	if (target && !S_ISREG(to_sb.st_mode)) {
305 		errno = EFTYPE;
306 		warn("%s", to_name);
307 		return;
308 	}
309 
310 	/* Only copy safe if the target exists. */
311 	tempcopy = safecopy && target;
312 
313 	if (!devnull && (from_fd = open(from_name, O_RDONLY, 0)) < 0)
314 		err(EX_OSERR, "%s", from_name);
315 
316 	/* If we don't strip, we can compare first. */
317 	if (docompare && !dostrip && target) {
318 		if ((to_fd = open(to_name, O_RDONLY, 0)) < 0)
319 			err(EX_OSERR, "%s", to_name);
320 		if (devnull)
321 			files_match = to_sb.st_size == 0;
322 		else
323 			files_match = !(compare(from_fd, from_name,
324 			    (size_t)from_sb.st_size, to_fd,
325 			    to_name, (size_t)to_sb.st_size));
326 
327 		/* Close "to" file unless we match. */
328 		if (!files_match)
329 			(void)close(to_fd);
330 	}
331 
332 	if (!files_match) {
333 		if (tempcopy) {
334 			to_fd = create_tempfile(to_name, tempfile,
335 			    sizeof(tempfile));
336 			if (to_fd < 0)
337 				err(EX_OSERR, "%s", tempfile);
338 		} else {
339 			if ((to_fd = create_newfile(to_name, target,
340 			    &to_sb)) < 0)
341 				err(EX_OSERR, "%s", to_name);
342 			if (verbose)
343 				(void)printf("install: %s -> %s\n",
344 				    from_name, to_name);
345 		}
346 		if (!devnull)
347 			copy(from_fd, from_name, to_fd,
348 			     tempcopy ? tempfile : to_name, from_sb.st_size);
349 	}
350 
351 	if (dostrip) {
352 		strip(tempcopy ? tempfile : to_name);
353 
354 		/*
355 		 * Re-open our fd on the target, in case we used a strip
356 		 * that does not work in-place -- like GNU binutils strip.
357 		 */
358 		close(to_fd);
359 		to_fd = open(tempcopy ? tempfile : to_name, O_RDONLY, 0);
360 		if (to_fd < 0)
361 			err(EX_OSERR, "stripping %s", to_name);
362 	}
363 
364 	/*
365 	 * Compare the stripped temp file with the target.
366 	 */
367 	if (docompare && dostrip && target) {
368 		temp_fd = to_fd;
369 
370 		/* Re-open to_fd using the real target name. */
371 		if ((to_fd = open(to_name, O_RDONLY, 0)) < 0)
372 			err(EX_OSERR, "%s", to_name);
373 
374 		if (fstat(temp_fd, &temp_sb)) {
375 			serrno = errno;
376 			(void)unlink(tempfile);
377 			errno = serrno;
378 			err(EX_OSERR, "%s", tempfile);
379 		}
380 
381 		if (compare(temp_fd, tempfile, (size_t)temp_sb.st_size, to_fd,
382 			    to_name, (size_t)to_sb.st_size) == 0) {
383 			/*
384 			 * If target has more than one link we need to
385 			 * replace it in order to snap the extra links.
386 			 * Need to preserve target file times, though.
387 			 */
388 			if (to_sb.st_nlink != 1) {
389 				tvb[0].tv_sec = to_sb.st_atime;
390 				tvb[0].tv_usec = 0;
391 				tvb[1].tv_sec = to_sb.st_mtime;
392 				tvb[1].tv_usec = 0;
393 				(void)utimes(tempfile, tvb);
394 			} else {
395 				files_match = 1;
396 				(void)unlink(tempfile);
397 			}
398 			(void) close(temp_fd);
399 		}
400 	}
401 
402 	/*
403 	 * Move the new file into place if doing a safe copy
404 	 * and the files are different (or just not compared).
405 	 */
406 	if (tempcopy && !files_match) {
407 		/* Try to turn off the immutable bits. */
408 		if (to_sb.st_flags & NOCHANGEBITS)
409 			(void)chflags(to_name, to_sb.st_flags & ~NOCHANGEBITS);
410 		if (dobackup) {
411 			if ((size_t)snprintf(backup, MAXPATHLEN, "%s%s", to_name,
412 			    suffix) != strlen(to_name) + strlen(suffix)) {
413 				unlink(tempfile);
414 				errx(EX_OSERR, "%s: backup filename too long",
415 				    to_name);
416 			}
417 			if (verbose)
418 				(void)printf("install: %s -> %s\n", to_name, backup);
419 			if (rename(to_name, backup) < 0) {
420 				serrno = errno;
421 				unlink(tempfile);
422 				errno = serrno;
423 				err(EX_OSERR, "rename: %s to %s", to_name,
424 				     backup);
425 			}
426 		}
427 		if (verbose)
428 			(void)printf("install: %s -> %s\n", from_name, to_name);
429 		if (rename(tempfile, to_name) < 0) {
430 			serrno = errno;
431 			unlink(tempfile);
432 			errno = serrno;
433 			err(EX_OSERR, "rename: %s to %s",
434 			    tempfile, to_name);
435 		}
436 
437 		/* Re-open to_fd so we aren't hosed by the rename(2). */
438 		(void) close(to_fd);
439 		if ((to_fd = open(to_name, O_RDONLY, 0)) < 0)
440 			err(EX_OSERR, "%s", to_name);
441 	}
442 
443 	/*
444 	 * Preserve the timestamp of the source file if necessary.
445 	 */
446 	if (dopreserve && !files_match && !devnull) {
447 		tvb[0].tv_sec = from_sb.st_atime;
448 		tvb[0].tv_usec = 0;
449 		tvb[1].tv_sec = from_sb.st_mtime;
450 		tvb[1].tv_usec = 0;
451 		(void)utimes(to_name, tvb);
452 	}
453 
454 	if (fstat(to_fd, &to_sb) == -1) {
455 		serrno = errno;
456 		(void)unlink(to_name);
457 		errno = serrno;
458 		err(EX_OSERR, "%s", to_name);
459 	}
460 
461 	/*
462 	 * Set owner, group, mode for target; do the chown first,
463 	 * chown may lose the setuid bits.
464 	 */
465 	if ((gid != (gid_t)-1 && gid != to_sb.st_gid) ||
466 	    (uid != (uid_t)-1 && uid != to_sb.st_uid) ||
467 	    (mode != (to_sb.st_mode & ALLPERMS))) {
468 		/* Try to turn off the immutable bits. */
469 		if (to_sb.st_flags & NOCHANGEBITS)
470 			(void)fchflags(to_fd, to_sb.st_flags & ~NOCHANGEBITS);
471 	}
472 
473 	if ((gid != (gid_t)-1 && gid != to_sb.st_gid) ||
474 	    (uid != (uid_t)-1 && uid != to_sb.st_uid))
475 		if (fchown(to_fd, uid, gid) == -1) {
476 			serrno = errno;
477 			(void)unlink(to_name);
478 			errno = serrno;
479 			err(EX_OSERR,"%s: chown/chgrp", to_name);
480 		}
481 
482 	if (mode != (to_sb.st_mode & ALLPERMS))
483 		if (fchmod(to_fd, mode)) {
484 			serrno = errno;
485 			(void)unlink(to_name);
486 			errno = serrno;
487 			err(EX_OSERR, "%s: chmod", to_name);
488 		}
489 
490 	/*
491 	 * If provided a set of flags, set them, otherwise, preserve the
492 	 * flags, except for the dump flag.
493 	 * NFS does not support flags.  Ignore EOPNOTSUPP flags if we're just
494 	 * trying to turn off UF_NODUMP.  If we're trying to set real flags,
495 	 * then warn if the the fs doesn't support it, otherwise fail.
496 	 */
497 	if (!devnull && (flags & SETFLAGS ||
498 	    (from_sb.st_flags & ~UF_NODUMP) != to_sb.st_flags) &&
499 	    fchflags(to_fd,
500 	    flags & SETFLAGS ? fset : from_sb.st_flags & ~UF_NODUMP)) {
501 		if (flags & SETFLAGS) {
502 			if (errno == EOPNOTSUPP)
503 				warn("%s: chflags", to_name);
504 			else {
505 				serrno = errno;
506 				(void)unlink(to_name);
507 				errno = serrno;
508 				err(EX_OSERR, "%s: chflags", to_name);
509 			}
510 		}
511 	}
512 
513 	(void)close(to_fd);
514 	if (!devnull)
515 		(void)close(from_fd);
516 }
517 
518 /*
519  * compare --
520  *	compare two files; non-zero means files differ
521  */
522 int
523 compare(int from_fd, const char *from_name __unused, size_t from_len,
524 	int to_fd, const char *to_name __unused, size_t to_len)
525 {
526 	char *p, *q;
527 	int rv;
528 	int done_compare;
529 
530 	rv = 0;
531 	if (from_len != to_len)
532 		return 1;
533 
534 	if (from_len <= MAX_CMP_SIZE) {
535 		done_compare = 0;
536 		if (trymmap(from_fd) && trymmap(to_fd)) {
537 			p = mmap(NULL, from_len, PROT_READ, MAP_SHARED, from_fd, (off_t)0);
538 			if (p == (char *)MAP_FAILED)
539 				goto out;
540 			q = mmap(NULL, from_len, PROT_READ, MAP_SHARED, to_fd, (off_t)0);
541 			if (q == (char *)MAP_FAILED) {
542 				munmap(p, from_len);
543 				goto out;
544 			}
545 
546 			rv = memcmp(p, q, from_len);
547 			munmap(p, from_len);
548 			munmap(q, from_len);
549 			done_compare = 1;
550 		}
551 	out:
552 		if (!done_compare) {
553 			char buf1[MAXBSIZE];
554 			char buf2[MAXBSIZE];
555 			int n1, n2;
556 
557 			rv = 0;
558 			lseek(from_fd, 0, SEEK_SET);
559 			lseek(to_fd, 0, SEEK_SET);
560 			while (rv == 0) {
561 				n1 = read(from_fd, buf1, sizeof(buf1));
562 				if (n1 == 0)
563 					break;		/* EOF */
564 				else if (n1 > 0) {
565 					n2 = read(to_fd, buf2, n1);
566 					if (n2 == n1)
567 						rv = memcmp(buf1, buf2, n1);
568 					else
569 						rv = 1;	/* out of sync */
570 				} else
571 					rv = 1;		/* read failure */
572 			}
573 			lseek(from_fd, 0, SEEK_SET);
574 			lseek(to_fd, 0, SEEK_SET);
575 		}
576 	} else
577 		rv = 1;	/* don't bother in this case */
578 
579 	return rv;
580 }
581 
582 /*
583  * create_tempfile --
584  *	create a temporary file based on path and open it
585  */
586 int
587 create_tempfile(const char *path, char *temp, size_t tsize)
588 {
589 	char *p;
590 
591 	(void)strncpy(temp, path, tsize);
592 	temp[tsize - 1] = '\0';
593 	if ((p = strrchr(temp, '/')) != NULL)
594 		p++;
595 	else
596 		p = temp;
597 	(void)strncpy(p, "INS@XXXX", &temp[tsize - 1] - p);
598 	temp[tsize - 1] = '\0';
599 	return (mkstemp(temp));
600 }
601 
602 /*
603  * create_newfile --
604  *	create a new file, overwriting an existing one if necessary
605  */
606 int
607 create_newfile(const char *path, int target, struct stat *sbp)
608 {
609 	char backup[MAXPATHLEN];
610 	int saved_errno = 0;
611 	int newfd;
612 
613 	if (target) {
614 		/*
615 		 * Unlink now... avoid ETXTBSY errors later.  Try to turn
616 		 * off the append/immutable bits -- if we fail, go ahead,
617 		 * it might work.
618 		 */
619 		if (sbp->st_flags & NOCHANGEBITS)
620 			(void)chflags(path, sbp->st_flags & ~NOCHANGEBITS);
621 
622 		if (dobackup) {
623 			if ((size_t)snprintf(backup, MAXPATHLEN, "%s%s",
624 			    path, suffix) != strlen(path) + strlen(suffix))
625 				errx(EX_OSERR, "%s: backup filename too long",
626 				    path);
627 			(void)snprintf(backup, MAXPATHLEN, "%s%s",
628 			    path, suffix);
629 			if (verbose)
630 				(void)printf("install: %s -> %s\n",
631 				    path, backup);
632 			if (rename(path, backup) < 0)
633 				err(EX_OSERR, "rename: %s to %s", path, backup);
634 		} else
635 			if (unlink(path) < 0)
636 				saved_errno = errno;
637 	}
638 
639 	newfd = open(path, O_CREAT | O_RDWR | O_TRUNC, S_IRUSR | S_IWUSR);
640 	if (newfd < 0 && saved_errno != 0)
641 		errno = saved_errno;
642 	return newfd;
643 }
644 
645 /*
646  * copy --
647  *	copy from one file to another
648  */
649 void
650 copy(int from_fd, const char *from_name, int to_fd, const char *to_name,
651     off_t size)
652 {
653 	int nr, nw;
654 	int serrno;
655 	char *p, buf[MAXBSIZE];
656 	int done_copy;
657 
658 	/* Rewind file descriptors. */
659 	if (lseek(from_fd, (off_t)0, SEEK_SET) == (off_t)-1)
660 		err(EX_OSERR, "lseek: %s", from_name);
661 	if (lseek(to_fd, (off_t)0, SEEK_SET) == (off_t)-1)
662 		err(EX_OSERR, "lseek: %s", to_name);
663 
664 	/*
665 	 * Mmap and write if less than 8M (the limit is so we don't totally
666 	 * trash memory on big files.  This is really a minor hack, but it
667 	 * wins some CPU back.
668 	 */
669 	done_copy = 0;
670 	if (size <= 8 * 1048576 && trymmap(from_fd) &&
671 	    (p = mmap(NULL, (size_t)size, PROT_READ, MAP_SHARED,
672 		    from_fd, (off_t)0)) != (char *)MAP_FAILED) {
673 		if ((nw = write(to_fd, p, size)) != size) {
674 			serrno = errno;
675 			(void)unlink(to_name);
676 			errno = nw > 0 ? EIO : serrno;
677 			err(EX_OSERR, "%s", to_name);
678 		}
679 		done_copy = 1;
680 	}
681 	if (!done_copy) {
682 		while ((nr = read(from_fd, buf, sizeof(buf))) > 0)
683 			if ((nw = write(to_fd, buf, nr)) != nr) {
684 				serrno = errno;
685 				(void)unlink(to_name);
686 				errno = nw > 0 ? EIO : serrno;
687 				err(EX_OSERR, "%s", to_name);
688 			}
689 		if (nr != 0) {
690 			serrno = errno;
691 			(void)unlink(to_name);
692 			errno = serrno;
693 			err(EX_OSERR, "%s", from_name);
694 		}
695 	}
696 }
697 
698 /*
699  * strip --
700  *	use strip(1) to strip the target file
701  */
702 void
703 strip(const char *to_name)
704 {
705 	const char *stripbin;
706 	int serrno, status;
707 
708 	switch (fork()) {
709 	case -1:
710 		serrno = errno;
711 		(void)unlink(to_name);
712 		errno = serrno;
713 		err(EX_TEMPFAIL, "fork");
714 	case 0:
715 		stripbin = getenv("STRIPBIN");
716 		if (stripbin == NULL)
717 			stripbin = "strip";
718 		execlp(stripbin, stripbin, to_name, (char *)NULL);
719 		err(EX_OSERR, "exec(%s)", stripbin);
720 	default:
721 		if (wait(&status) == -1 || status) {
722 			serrno = errno;
723 			(void)unlink(to_name);
724 			errc(EX_SOFTWARE, serrno, "wait");
725 			/* NOTREACHED */
726 		}
727 	}
728 }
729 
730 /*
731  * install_dir --
732  *	build directory heirarchy
733  */
734 void
735 install_dir(char *path)
736 {
737 	char *p;
738 	struct stat sb;
739 	int ch;
740 
741 	for (p = path;; ++p)
742 		if (!*p || (p != path && *p  == '/')) {
743 			ch = *p;
744 			*p = '\0';
745 			if (stat(path, &sb)) {
746 				if (errno != ENOENT || mkdir(path, 0755) < 0) {
747 					err(EX_OSERR, "mkdir %s", path);
748 					/* NOTREACHED */
749 				} else if (verbose)
750 					(void)printf("install: mkdir %s\n",
751 						     path);
752 			} else if (!S_ISDIR(sb.st_mode))
753 				errx(EX_OSERR, "%s exists but is not a directory", path);
754 			if (!(*p = ch))
755 				break;
756  		}
757 
758 	if ((gid != (gid_t)-1 || uid != (uid_t)-1) && chown(path, uid, gid))
759 		warn("chown %u:%u %s", uid, gid, path);
760 	if (chmod(path, mode))
761 		warn("chmod %o %s", mode, path);
762 }
763 
764 /*
765  * usage --
766  *	print a usage message and die
767  */
768 void
769 usage()
770 {
771 	(void)fprintf(stderr,
772 "usage: install [-bCcpSsv] [-B suffix] [-f flags] [-g group] [-m mode]\n"
773 "               [-o owner] file1 file2\n"
774 "       install [-bCcpSsv] [-B suffix] [-f flags] [-g group] [-m mode]\n"
775 "               [-o owner] file1 ... fileN directory\n"
776 "       install -d [-v] [-g group] [-m mode] [-o owner] directory ...\n");
777 	exit(EX_USAGE);
778 	/* NOTREACHED */
779 }
780 
781 /*
782  * trymmap --
783  *	return true (1) if mmap should be tried, false (0) if not.
784  */
785 int
786 trymmap(int fd)
787 {
788 /*
789  * The ifdef is for bootstrapping - f_fstypename doesn't exist in
790  * pre-Lite2-merge systems.
791  */
792 #ifdef MFSNAMELEN
793 	struct statfs stfs;
794 
795 	if (nommap || fstatfs(fd, &stfs) != 0)
796 		return (0);
797 	if (strcmp(stfs.f_fstypename, "ufs") == 0 ||
798 	    strcmp(stfs.f_fstypename, "cd9660") == 0)
799 		return (1);
800 #endif
801 	return (0);
802 }
803