xref: /freebsd/sbin/restore/tape.c (revision eacee0ff7ec955b32e09515246bd97b6edcd2b0f)
1 /*
2  * Copyright (c) 1983, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  * (c) UNIX System Laboratories, Inc.
5  * All or some portions of this file are derived from material licensed
6  * to the University of California by American Telephone and Telegraph
7  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8  * the permission of UNIX System Laboratories, Inc.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the University of
21  *	California, Berkeley and its contributors.
22  * 4. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  */
38 
39 #ifndef lint
40 #if 0
41 static char sccsid[] = "@(#)tape.c	8.9 (Berkeley) 5/1/95";
42 #endif
43 static const char rcsid[] =
44   "$FreeBSD$";
45 #endif /* not lint */
46 
47 #include <sys/param.h>
48 #include <sys/file.h>
49 #include <sys/mtio.h>
50 #include <sys/stat.h>
51 #include <sys/time.h>
52 
53 #include <ufs/ufs/dinode.h>
54 #include <protocols/dumprestore.h>
55 
56 #include <errno.h>
57 #include <paths.h>
58 #include <setjmp.h>
59 #include <stdio.h>
60 #include <stdlib.h>
61 #include <string.h>
62 #include <time.h>
63 #include <unistd.h>
64 
65 #include "restore.h"
66 #include "extern.h"
67 
68 static long	fssize = MAXBSIZE;
69 static int	mt = -1;
70 static int	pipein = 0;
71 static char	*magtape;
72 static int	blkcnt;
73 static int	numtrec;
74 static char	*tapebuf;
75 static union	u_spcl endoftapemark;
76 static long	blksread;		/* blocks read since last header */
77 static long	tapeaddr = 0;		/* current TP_BSIZE tape record */
78 static long	tapesread;
79 static jmp_buf	restart;
80 static int	gettingfile = 0;	/* restart has a valid frame */
81 static char	*host = NULL;
82 
83 static int	ofile;
84 static char	*map;
85 static char	lnkbuf[MAXPATHLEN + 1];
86 static int	pathlen;
87 
88 int		oldinofmt;	/* old inode format conversion required */
89 int		Bcvt;		/* Swap Bytes (for CCI or sun) */
90 static int	Qcvt;		/* Swap quads (for sun) */
91 
92 #define	FLUSHTAPEBUF()	blkcnt = ntrec + 1
93 
94 static void	 accthdr __P((struct s_spcl *));
95 static int	 checksum __P((int *));
96 static void	 findinode __P((struct s_spcl *));
97 static void	 findtapeblksize __P((void));
98 static int	 gethead __P((struct s_spcl *));
99 static void	 readtape __P((char *));
100 static void	 setdumpnum __P((void));
101 static u_long	 swabl __P((u_long));
102 static u_char	*swablong __P((u_char *, int));
103 static u_char	*swabshort __P((u_char *, int));
104 static void	 terminateinput __P((void));
105 static void	 xtrfile __P((char *, long));
106 static void	 xtrlnkfile __P((char *, long));
107 static void	 xtrlnkskip __P((char *, long));
108 static void	 xtrmap __P((char *, long));
109 static void	 xtrmapskip __P((char *, long));
110 static void	 xtrskip __P((char *, long));
111 
112 static int readmapflag;
113 
114 /*
115  * Set up an input source
116  */
117 void
118 setinput(source)
119 	char *source;
120 {
121 	FLUSHTAPEBUF();
122 	if (bflag)
123 		newtapebuf(ntrec);
124 	else
125 		newtapebuf(NTREC > HIGHDENSITYTREC ? NTREC : HIGHDENSITYTREC);
126 	terminal = stdin;
127 
128 #ifdef RRESTORE
129 	if (strchr(source, ':')) {
130 		host = source;
131 		source = strchr(host, ':');
132 		*source++ = '\0';
133 		if (rmthost(host) == 0)
134 			done(1);
135 	} else
136 #endif
137 	if (strcmp(source, "-") == 0) {
138 		/*
139 		 * Since input is coming from a pipe we must establish
140 		 * our own connection to the terminal.
141 		 */
142 		terminal = fopen(_PATH_TTY, "r");
143 		if (terminal == NULL) {
144 			(void)fprintf(stderr, "cannot open %s: %s\n",
145 			    _PATH_TTY, strerror(errno));
146 			terminal = fopen(_PATH_DEVNULL, "r");
147 			if (terminal == NULL) {
148 				(void)fprintf(stderr, "cannot open %s: %s\n",
149 				    _PATH_DEVNULL, strerror(errno));
150 				done(1);
151 			}
152 		}
153 		pipein++;
154 	}
155 	setuid(getuid());	/* no longer need or want root privileges */
156 	magtape = strdup(source);
157 	if (magtape == NULL) {
158 		fprintf(stderr, "Cannot allocate space for magtape buffer\n");
159 		done(1);
160 	}
161 }
162 
163 void
164 newtapebuf(size)
165 	long size;
166 {
167 	static tapebufsize = -1;
168 
169 	ntrec = size;
170 	if (size <= tapebufsize)
171 		return;
172 	if (tapebuf != NULL)
173 		free(tapebuf);
174 	tapebuf = malloc(size * TP_BSIZE);
175 	if (tapebuf == NULL) {
176 		fprintf(stderr, "Cannot allocate space for tape buffer\n");
177 		done(1);
178 	}
179 	tapebufsize = size;
180 }
181 
182 /*
183  * Verify that the tape drive can be accessed and
184  * that it actually is a dump tape.
185  */
186 void
187 setup()
188 {
189 	int i, j, *ip;
190 	struct stat stbuf;
191 
192 	vprintf(stdout, "Verify tape and initialize maps\n");
193 #ifdef RRESTORE
194 	if (host)
195 		mt = rmtopen(magtape, 0);
196 	else
197 #endif
198 	if (pipein)
199 		mt = 0;
200 	else
201 		mt = open(magtape, O_RDONLY, 0);
202 	if (mt < 0) {
203 		fprintf(stderr, "%s: %s\n", magtape, strerror(errno));
204 		done(1);
205 	}
206 	volno = 1;
207 	setdumpnum();
208 	FLUSHTAPEBUF();
209 	if (!pipein && !bflag)
210 		findtapeblksize();
211 	if (gethead(&spcl) == FAIL) {
212 		blkcnt--; /* push back this block */
213 		blksread--;
214 		cvtflag++;
215 		if (gethead(&spcl) == FAIL) {
216 			fprintf(stderr, "Tape is not a dump tape\n");
217 			done(1);
218 		}
219 		fprintf(stderr, "Converting to new file system format.\n");
220 	}
221 	if (pipein) {
222 		endoftapemark.s_spcl.c_magic = cvtflag ? OFS_MAGIC : NFS_MAGIC;
223 		endoftapemark.s_spcl.c_type = TS_END;
224 		ip = (int *)&endoftapemark;
225 		j = sizeof(union u_spcl) / sizeof(int);
226 		i = 0;
227 		do
228 			i += *ip++;
229 		while (--j);
230 		endoftapemark.s_spcl.c_checksum = CHECKSUM - i;
231 	}
232 	if (vflag || command == 't')
233 		printdumpinfo();
234 	dumptime = _time32_to_time(spcl.c_ddate);
235 	dumpdate = _time32_to_time(spcl.c_date);
236 	if (stat(".", &stbuf) < 0) {
237 		fprintf(stderr, "cannot stat .: %s\n", strerror(errno));
238 		done(1);
239 	}
240 	if (stbuf.st_blksize > 0 && stbuf.st_blksize < TP_BSIZE )
241 		fssize = TP_BSIZE;
242 	if (stbuf.st_blksize >= TP_BSIZE && stbuf.st_blksize <= MAXBSIZE)
243 		fssize = stbuf.st_blksize;
244 	if (((fssize - 1) & fssize) != 0) {
245 		fprintf(stderr, "bad block size %ld\n", fssize);
246 		done(1);
247 	}
248 	if (spcl.c_volume != 1) {
249 		fprintf(stderr, "Tape is not volume 1 of the dump\n");
250 		done(1);
251 	}
252 	if (gethead(&spcl) == FAIL) {
253 		dprintf(stdout, "header read failed at %ld blocks\n", blksread);
254 		panic("no header after volume mark!\n");
255 	}
256 	findinode(&spcl);
257 	if (spcl.c_type != TS_CLRI) {
258 		fprintf(stderr, "Cannot find file removal list\n");
259 		done(1);
260 	}
261 	maxino = (spcl.c_count * TP_BSIZE * NBBY) + 1;
262 	dprintf(stdout, "maxino = %d\n", maxino);
263 	map = calloc((unsigned)1, (unsigned)howmany(maxino, NBBY));
264 	if (map == NULL)
265 		panic("no memory for active inode map\n");
266 	usedinomap = map;
267 	curfile.action = USING;
268 	getfile(xtrmap, xtrmapskip);
269 	if (spcl.c_type != TS_BITS) {
270 		fprintf(stderr, "Cannot find file dump list\n");
271 		done(1);
272 	}
273 	map = calloc((unsigned)1, (unsigned)howmany(maxino, NBBY));
274 	if (map == (char *)NULL)
275 		panic("no memory for file dump list\n");
276 	dumpmap = map;
277 	curfile.action = USING;
278 	getfile(xtrmap, xtrmapskip);
279 	/*
280 	 * If there may be whiteout entries on the tape, pretend that the
281 	 * whiteout inode exists, so that the whiteout entries can be
282 	 * extracted.
283 	 */
284 	if (oldinofmt == 0)
285 		SETINO(WINO, dumpmap);
286 	/* 'r' restores don't call getvol() for tape 1, so mark it as read. */
287 	if (command == 'r')
288 		tapesread = 1;
289 }
290 
291 /*
292  * Prompt user to load a new dump volume.
293  * "Nextvol" is the next suggested volume to use.
294  * This suggested volume is enforced when doing full
295  * or incremental restores, but can be overridden by
296  * the user when only extracting a subset of the files.
297  */
298 void
299 getvol(nextvol)
300 	long nextvol;
301 {
302 	long newvol, prevtapea, savecnt, i;
303 	union u_spcl tmpspcl;
304 #	define tmpbuf tmpspcl.s_spcl
305 	char buf[TP_BSIZE];
306 
307 	if (nextvol == 1) {
308 		tapesread = 0;
309 		gettingfile = 0;
310 	}
311 	prevtapea = tapeaddr;
312 	savecnt = blksread;
313 	if (pipein) {
314 		if (nextvol != 1) {
315 			panic("Changing volumes on pipe input?\n");
316 			/* Avoid looping if we couldn't ask the user. */
317 			if (yflag || ferror(terminal) || feof(terminal))
318 				done(1);
319 		}
320 		if (volno == 1)
321 			return;
322 		goto gethdr;
323 	}
324 again:
325 	if (pipein)
326 		done(1); /* pipes do not get a second chance */
327 	if (command == 'R' || command == 'r' || curfile.action != SKIP)
328 		newvol = nextvol;
329 	else
330 		newvol = 0;
331 	while (newvol <= 0) {
332 		if (tapesread == 0) {
333 			fprintf(stderr, "%s%s%s%s%s%s%s",
334 			    "You have not read any tapes yet.\n",
335 			    "If you are extracting just a few files,",
336 			    " start with the last volume\n",
337 			    "and work towards the first; restore",
338 			    " can quickly skip tapes that\n",
339 			    "have no further files to extract.",
340 			    " Otherwise, begin with volume 1.\n");
341 		} else {
342 			fprintf(stderr, "You have read volumes");
343 			strcpy(buf, ": ");
344 			for (i = 0; i < 32; i++)
345 				if (tapesread & (1 << i)) {
346 					fprintf(stderr, "%s%ld", buf, i + 1);
347 					strcpy(buf, ", ");
348 				}
349 			fprintf(stderr, "\n");
350 		}
351 		do	{
352 			fprintf(stderr, "Specify next volume #: ");
353 			(void) fflush(stderr);
354 			if (fgets(buf, BUFSIZ, terminal) == NULL)
355 				done(1);
356 		} while (buf[0] == '\n');
357 		newvol = atoi(buf);
358 		if (newvol <= 0) {
359 			fprintf(stderr,
360 			    "Volume numbers are positive numerics\n");
361 		}
362 	}
363 	if (newvol == volno) {
364 		tapesread |= 1 << (volno - 1);
365 		return;
366 	}
367 	closemt();
368 	fprintf(stderr, "Mount tape volume %ld\n", newvol);
369 	fprintf(stderr, "Enter ``none'' if there are no more tapes\n");
370 	fprintf(stderr, "otherwise enter tape name (default: %s) ", magtape);
371 	(void) fflush(stderr);
372 	if (fgets(buf, BUFSIZ, terminal) == NULL)
373 		done(1);
374 	if (!strcmp(buf, "none\n")) {
375 		terminateinput();
376 		return;
377 	}
378 	if (buf[0] != '\n') {
379 		(void) strcpy(magtape, buf);
380 		magtape[strlen(magtape) - 1] = '\0';
381 	}
382 #ifdef RRESTORE
383 	if (host)
384 		mt = rmtopen(magtape, 0);
385 	else
386 #endif
387 		mt = open(magtape, O_RDONLY, 0);
388 
389 	if (mt == -1) {
390 		fprintf(stderr, "Cannot open %s\n", magtape);
391 		volno = -1;
392 		goto again;
393 	}
394 gethdr:
395 	volno = newvol;
396 	setdumpnum();
397 	FLUSHTAPEBUF();
398 	if (gethead(&tmpbuf) == FAIL) {
399 		dprintf(stdout, "header read failed at %ld blocks\n", blksread);
400 		fprintf(stderr, "tape is not dump tape\n");
401 		volno = 0;
402 		goto again;
403 	}
404 	if (tmpbuf.c_volume != volno) {
405 		fprintf(stderr, "Wrong volume (%ld)\n", tmpbuf.c_volume);
406 		volno = 0;
407 		goto again;
408 	}
409 	if (_time32_to_time(tmpbuf.c_date) != dumpdate ||
410 	    _time32_to_time(tmpbuf.c_ddate) != dumptime) {
411 		time_t t = _time32_to_time(tmpbuf.c_date);
412 		fprintf(stderr, "Wrong dump date\n\tgot: %s", ctime(&t));
413 		fprintf(stderr, "\twanted: %s", ctime(&dumpdate));
414 		volno = 0;
415 		goto again;
416 	}
417 	tapesread |= 1 << (volno - 1);
418 	blksread = savecnt;
419  	/*
420  	 * If continuing from the previous volume, skip over any
421  	 * blocks read already at the end of the previous volume.
422  	 *
423  	 * If coming to this volume at random, skip to the beginning
424  	 * of the next record.
425  	 */
426 	dprintf(stdout, "last rec %ld, tape starts with %ld\n", prevtapea,
427 	    tmpbuf.c_tapea);
428  	if (tmpbuf.c_type == TS_TAPE && (tmpbuf.c_flags & DR_NEWHEADER)) {
429  		if (curfile.action != USING) {
430 			/*
431 			 * XXX Dump incorrectly sets c_count to 1 in the
432 			 * volume header of the first tape, so ignore
433 			 * c_count when volno == 1.
434 			 */
435 			if (volno != 1)
436 				for (i = tmpbuf.c_count; i > 0; i--)
437 					readtape(buf);
438  		} else if (tmpbuf.c_tapea <= prevtapea) {
439 			/*
440 			 * Normally the value of c_tapea in the volume
441 			 * header is the record number of the header itself.
442 			 * However in the volume header following an EOT-
443 			 * terminated tape, it is the record number of the
444 			 * first continuation data block (dump bug?).
445 			 *
446 			 * The next record we want is `prevtapea + 1'.
447 			 */
448  			i = prevtapea + 1 - tmpbuf.c_tapea;
449 			dprintf(stderr, "Skipping %ld duplicate record%s.\n",
450 				i, i > 1 ? "s" : "");
451  			while (--i >= 0)
452  				readtape(buf);
453  		}
454  	}
455 	if (curfile.action == USING) {
456 		if (volno == 1)
457 			panic("active file into volume 1\n");
458 		return;
459 	}
460 	(void) gethead(&spcl);
461 	findinode(&spcl);
462 	if (gettingfile) {
463 		gettingfile = 0;
464 		longjmp(restart, 1);
465 	}
466 }
467 
468 /*
469  * Handle unexpected EOF.
470  */
471 static void
472 terminateinput()
473 {
474 
475 	if (gettingfile && curfile.action == USING) {
476 		printf("Warning: %s %s\n",
477 		    "End-of-input encountered while extracting", curfile.name);
478 	}
479 	curfile.name = "<name unknown>";
480 	curfile.action = UNKNOWN;
481 	curfile.dip = NULL;
482 	curfile.ino = maxino;
483 	if (gettingfile) {
484 		gettingfile = 0;
485 		longjmp(restart, 1);
486 	}
487 }
488 
489 /*
490  * handle multiple dumps per tape by skipping forward to the
491  * appropriate one.
492  */
493 static void
494 setdumpnum()
495 {
496 	struct mtop tcom;
497 
498 	if (dumpnum == 1 || volno != 1)
499 		return;
500 	if (pipein) {
501 		fprintf(stderr, "Cannot have multiple dumps on pipe input\n");
502 		done(1);
503 	}
504 	tcom.mt_op = MTFSF;
505 	tcom.mt_count = dumpnum - 1;
506 #ifdef RRESTORE
507 	if (host)
508 		rmtioctl(MTFSF, dumpnum - 1);
509 	else
510 #endif
511 		if (ioctl(mt, MTIOCTOP, (char *)&tcom) < 0)
512 			fprintf(stderr, "ioctl MTFSF: %s\n", strerror(errno));
513 }
514 
515 void
516 printdumpinfo()
517 {
518 	time_t t;
519 	t = _time32_to_time(spcl.c_date);
520 	fprintf(stdout, "Dump   date: %s", ctime(&t));
521 	t = _time32_to_time(spcl.c_ddate);
522 	fprintf(stdout, "Dumped from: %s",
523 	    (spcl.c_ddate == 0) ? "the epoch\n" : ctime(&t));
524 	if (spcl.c_host[0] == '\0')
525 		return;
526 	fprintf(stderr, "Level %ld dump of %s on %s:%s\n",
527 		spcl.c_level, spcl.c_filesys, spcl.c_host, spcl.c_dev);
528 	fprintf(stderr, "Label: %s\n", spcl.c_label);
529 }
530 
531 int
532 extractfile(name)
533 	char *name;
534 {
535 	int flags;
536 	mode_t mode;
537 	struct timeval timep[2];
538 	struct entry *ep;
539 
540 	curfile.name = name;
541 	curfile.action = USING;
542 	timep[0].tv_sec = curfile.dip->di_atime;
543 	timep[0].tv_usec = curfile.dip->di_atimensec / 1000;
544 	timep[1].tv_sec = curfile.dip->di_mtime;
545 	timep[1].tv_usec = curfile.dip->di_mtimensec / 1000;
546 	mode = curfile.dip->di_mode;
547 	flags = curfile.dip->di_flags;
548 	switch (mode & IFMT) {
549 
550 	default:
551 		fprintf(stderr, "%s: unknown file mode 0%o\n", name, mode);
552 		skipfile();
553 		return (FAIL);
554 
555 	case IFSOCK:
556 		vprintf(stdout, "skipped socket %s\n", name);
557 		skipfile();
558 		return (GOOD);
559 
560 	case IFDIR:
561 		if (mflag) {
562 			ep = lookupname(name);
563 			if (ep == NULL || ep->e_flags & EXTRACT)
564 				panic("unextracted directory %s\n", name);
565 			skipfile();
566 			return (GOOD);
567 		}
568 		vprintf(stdout, "extract file %s\n", name);
569 		return (genliteraldir(name, curfile.ino));
570 
571 	case IFLNK:
572 		lnkbuf[0] = '\0';
573 		pathlen = 0;
574 		getfile(xtrlnkfile, xtrlnkskip);
575 		if (pathlen == 0) {
576 			vprintf(stdout,
577 			    "%s: zero length symbolic link (ignored)\n", name);
578 			return (GOOD);
579 		}
580 		return (linkit(lnkbuf, name, SYMLINK));
581 
582 	case IFIFO:
583 		vprintf(stdout, "extract fifo %s\n", name);
584 		if (Nflag) {
585 			skipfile();
586 			return (GOOD);
587 		}
588 		if (uflag && !Nflag)
589 			(void)unlink(name);
590 		if (mkfifo(name, mode) < 0) {
591 			fprintf(stderr, "%s: cannot create fifo: %s\n",
592 			    name, strerror(errno));
593 			skipfile();
594 			return (FAIL);
595 		}
596 		(void) chown(name, curfile.dip->di_uid, curfile.dip->di_gid);
597 		(void) chmod(name, mode);
598 		utimes(name, timep);
599 		(void) chflags(name, flags);
600 		skipfile();
601 		return (GOOD);
602 
603 	case IFCHR:
604 	case IFBLK:
605 		vprintf(stdout, "extract special file %s\n", name);
606 		if (Nflag) {
607 			skipfile();
608 			return (GOOD);
609 		}
610 		if (uflag)
611 			(void)unlink(name);
612 		if (mknod(name, mode, (int)curfile.dip->di_rdev) < 0) {
613 			fprintf(stderr, "%s: cannot create special file: %s\n",
614 			    name, strerror(errno));
615 			skipfile();
616 			return (FAIL);
617 		}
618 		(void) chown(name, curfile.dip->di_uid, curfile.dip->di_gid);
619 		(void) chmod(name, mode);
620 		utimes(name, timep);
621 		(void) chflags(name, flags);
622 		skipfile();
623 		return (GOOD);
624 
625 	case IFREG:
626 		vprintf(stdout, "extract file %s\n", name);
627 		if (Nflag) {
628 			skipfile();
629 			return (GOOD);
630 		}
631 		if (uflag)
632 			(void)unlink(name);
633 		if ((ofile = open(name, O_WRONLY | O_CREAT | O_TRUNC,
634 		    0666)) < 0) {
635 			fprintf(stderr, "%s: cannot create file: %s\n",
636 			    name, strerror(errno));
637 			skipfile();
638 			return (FAIL);
639 		}
640 		(void) fchown(ofile, curfile.dip->di_uid, curfile.dip->di_gid);
641 		(void) fchmod(ofile, mode);
642 		getfile(xtrfile, xtrskip);
643 		(void) close(ofile);
644 		utimes(name, timep);
645 		(void) chflags(name, flags);
646 		return (GOOD);
647 	}
648 	/* NOTREACHED */
649 }
650 
651 /*
652  * skip over bit maps on the tape
653  */
654 void
655 skipmaps()
656 {
657 
658 	while (spcl.c_type == TS_BITS || spcl.c_type == TS_CLRI)
659 		skipfile();
660 }
661 
662 /*
663  * skip over a file on the tape
664  */
665 void
666 skipfile()
667 {
668 
669 	curfile.action = SKIP;
670 	getfile(xtrnull, xtrnull);
671 }
672 
673 /*
674  * Extract a file from the tape.
675  * When an allocated block is found it is passed to the fill function;
676  * when an unallocated block (hole) is found, a zeroed buffer is passed
677  * to the skip function.
678  */
679 void
680 getfile(fill, skip)
681 	void	(*fill) __P((char *, long));
682 	void	(*skip) __P((char *, long));
683 {
684 	register int i;
685 	int curblk = 0;
686 	quad_t size = spcl.c_dinode.di_size;
687 	static char clearedbuf[MAXBSIZE];
688 	char buf[MAXBSIZE / TP_BSIZE][TP_BSIZE];
689 	char junk[TP_BSIZE];
690 
691 	if (spcl.c_type == TS_END)
692 		panic("ran off end of tape\n");
693 	if (spcl.c_magic != NFS_MAGIC)
694 		panic("not at beginning of a file\n");
695 	if (!gettingfile && setjmp(restart) != 0)
696 		return;
697 	gettingfile++;
698 loop:
699 	for (i = 0; i < spcl.c_count; i++) {
700 		if (readmapflag || spcl.c_addr[i]) {
701 			readtape(&buf[curblk++][0]);
702 			if (curblk == fssize / TP_BSIZE) {
703 				(*fill)((char *)buf, (long)(size > TP_BSIZE ?
704 				     fssize : (curblk - 1) * TP_BSIZE + size));
705 				curblk = 0;
706 			}
707 		} else {
708 			if (curblk > 0) {
709 				(*fill)((char *)buf, (long)(size > TP_BSIZE ?
710 				     curblk * TP_BSIZE :
711 				     (curblk - 1) * TP_BSIZE + size));
712 				curblk = 0;
713 			}
714 			(*skip)(clearedbuf, (long)(size > TP_BSIZE ?
715 				TP_BSIZE : size));
716 		}
717 		if ((size -= TP_BSIZE) <= 0) {
718 			for (i++; i < spcl.c_count; i++)
719 				if (readmapflag || spcl.c_addr[i])
720 					readtape(junk);
721 			break;
722 		}
723 	}
724 	if (gethead(&spcl) == GOOD && size > 0) {
725 		if (spcl.c_type == TS_ADDR)
726 			goto loop;
727 		dprintf(stdout,
728 			"Missing address (header) block for %s at %ld blocks\n",
729 			curfile.name, blksread);
730 	}
731 	if (curblk > 0)
732 		(*fill)((char *)buf, (long)((curblk * TP_BSIZE) + size));
733 	findinode(&spcl);
734 	gettingfile = 0;
735 }
736 
737 /*
738  * Write out the next block of a file.
739  */
740 static void
741 xtrfile(buf, size)
742 	char	*buf;
743 	long	size;
744 {
745 
746 	if (Nflag)
747 		return;
748 	if (write(ofile, buf, (int) size) == -1) {
749 		fprintf(stderr,
750 		    "write error extracting inode %d, name %s\nwrite: %s\n",
751 			curfile.ino, curfile.name, strerror(errno));
752 	}
753 }
754 
755 /*
756  * Skip over a hole in a file.
757  */
758 /* ARGSUSED */
759 static void
760 xtrskip(buf, size)
761 	char *buf;
762 	long size;
763 {
764 
765 	if (lseek(ofile, size, SEEK_CUR) == -1) {
766 		fprintf(stderr,
767 		    "seek error extracting inode %d, name %s\nlseek: %s\n",
768 			curfile.ino, curfile.name, strerror(errno));
769 		done(1);
770 	}
771 }
772 
773 /*
774  * Collect the next block of a symbolic link.
775  */
776 static void
777 xtrlnkfile(buf, size)
778 	char	*buf;
779 	long	size;
780 {
781 
782 	pathlen += size;
783 	if (pathlen > MAXPATHLEN) {
784 		fprintf(stderr, "symbolic link name: %s->%s%s; too long %d\n",
785 		    curfile.name, lnkbuf, buf, pathlen);
786 		done(1);
787 	}
788 	(void) strcat(lnkbuf, buf);
789 }
790 
791 /*
792  * Skip over a hole in a symbolic link (should never happen).
793  */
794 /* ARGSUSED */
795 static void
796 xtrlnkskip(buf, size)
797 	char *buf;
798 	long size;
799 {
800 
801 	fprintf(stderr, "unallocated block in symbolic link %s\n",
802 		curfile.name);
803 	done(1);
804 }
805 
806 /*
807  * Collect the next block of a bit map.
808  */
809 static void
810 xtrmap(buf, size)
811 	char	*buf;
812 	long	size;
813 {
814 
815 	memmove(map, buf, size);
816 	map += size;
817 }
818 
819 /*
820  * Skip over a hole in a bit map (should never happen).
821  */
822 /* ARGSUSED */
823 static void
824 xtrmapskip(buf, size)
825 	char *buf;
826 	long size;
827 {
828 
829 	panic("hole in map\n");
830 	map += size;
831 }
832 
833 /*
834  * Noop, when an extraction function is not needed.
835  */
836 /* ARGSUSED */
837 void
838 xtrnull(buf, size)
839 	char *buf;
840 	long size;
841 {
842 
843 	return;
844 }
845 
846 /*
847  * Read TP_BSIZE blocks from the input.
848  * Handle read errors, and end of media.
849  */
850 static void
851 readtape(buf)
852 	char *buf;
853 {
854 	long rd, newvol, i;
855 	int cnt, seek_failed;
856 
857 	if (blkcnt < numtrec) {
858 		memmove(buf, &tapebuf[(blkcnt++ * TP_BSIZE)], (long)TP_BSIZE);
859 		blksread++;
860 		tapeaddr++;
861 		return;
862 	}
863 	for (i = 0; i < ntrec; i++)
864 		((struct s_spcl *)&tapebuf[i * TP_BSIZE])->c_magic = 0;
865 	if (numtrec == 0)
866 		numtrec = ntrec;
867 	cnt = ntrec * TP_BSIZE;
868 	rd = 0;
869 getmore:
870 #ifdef RRESTORE
871 	if (host)
872 		i = rmtread(&tapebuf[rd], cnt);
873 	else
874 #endif
875 		i = read(mt, &tapebuf[rd], cnt);
876 	/*
877 	 * Check for mid-tape short read error.
878 	 * If found, skip rest of buffer and start with the next.
879 	 */
880 	if (!pipein && numtrec < ntrec && i > 0) {
881 		dprintf(stdout, "mid-media short read error.\n");
882 		numtrec = ntrec;
883 	}
884 	/*
885 	 * Handle partial block read.
886 	 */
887 	if (pipein && i == 0 && rd > 0)
888 		i = rd;
889 	else if (i > 0 && i != ntrec * TP_BSIZE) {
890 		if (pipein) {
891 			rd += i;
892 			cnt -= i;
893 			if (cnt > 0)
894 				goto getmore;
895 			i = rd;
896 		} else {
897 			/*
898 			 * Short read. Process the blocks read.
899 			 */
900 			if (i % TP_BSIZE != 0)
901 				vprintf(stdout,
902 				    "partial block read: %ld should be %ld\n",
903 				    i, ntrec * TP_BSIZE);
904 			numtrec = i / TP_BSIZE;
905 		}
906 	}
907 	/*
908 	 * Handle read error.
909 	 */
910 	if (i < 0) {
911 		fprintf(stderr, "Tape read error while ");
912 		switch (curfile.action) {
913 		default:
914 			fprintf(stderr, "trying to set up tape\n");
915 			break;
916 		case UNKNOWN:
917 			fprintf(stderr, "trying to resynchronize\n");
918 			break;
919 		case USING:
920 			fprintf(stderr, "restoring %s\n", curfile.name);
921 			break;
922 		case SKIP:
923 			fprintf(stderr, "skipping over inode %d\n",
924 				curfile.ino);
925 			break;
926 		}
927 		if (!yflag && !reply("continue"))
928 			done(1);
929 		i = ntrec * TP_BSIZE;
930 		memset(tapebuf, 0, i);
931 #ifdef RRESTORE
932 		if (host)
933 			seek_failed = (rmtseek(i, 1) < 0);
934 		else
935 #endif
936 			seek_failed = (lseek(mt, i, SEEK_CUR) == (off_t)-1);
937 
938 		if (seek_failed) {
939 			fprintf(stderr,
940 			    "continuation failed: %s\n", strerror(errno));
941 			done(1);
942 		}
943 	}
944 	/*
945 	 * Handle end of tape.
946 	 */
947 	if (i == 0) {
948 		vprintf(stdout, "End-of-tape encountered\n");
949 		if (!pipein) {
950 			newvol = volno + 1;
951 			volno = 0;
952 			numtrec = 0;
953 			getvol(newvol);
954 			readtape(buf);
955 			return;
956 		}
957 		if (rd % TP_BSIZE != 0)
958 			panic("partial block read: %d should be %d\n",
959 				rd, ntrec * TP_BSIZE);
960 		terminateinput();
961 		memmove(&tapebuf[rd], &endoftapemark, (long)TP_BSIZE);
962 	}
963 	blkcnt = 0;
964 	memmove(buf, &tapebuf[(blkcnt++ * TP_BSIZE)], (long)TP_BSIZE);
965 	blksread++;
966 	tapeaddr++;
967 }
968 
969 static void
970 findtapeblksize()
971 {
972 	register long i;
973 
974 	for (i = 0; i < ntrec; i++)
975 		((struct s_spcl *)&tapebuf[i * TP_BSIZE])->c_magic = 0;
976 	blkcnt = 0;
977 #ifdef RRESTORE
978 	if (host)
979 		i = rmtread(tapebuf, ntrec * TP_BSIZE);
980 	else
981 #endif
982 		i = read(mt, tapebuf, ntrec * TP_BSIZE);
983 
984 	if (i <= 0) {
985 		fprintf(stderr, "tape read error: %s\n", strerror(errno));
986 		done(1);
987 	}
988 	if (i % TP_BSIZE != 0) {
989 		fprintf(stderr, "Tape block size (%ld) %s (%d)\n",
990 			i, "is not a multiple of dump block size", TP_BSIZE);
991 		done(1);
992 	}
993 	ntrec = i / TP_BSIZE;
994 	numtrec = ntrec;
995 	vprintf(stdout, "Tape block size is %ld\n", ntrec);
996 }
997 
998 void
999 closemt()
1000 {
1001 
1002 	if (mt < 0)
1003 		return;
1004 #ifdef RRESTORE
1005 	if (host)
1006 		rmtclose();
1007 	else
1008 #endif
1009 		(void) close(mt);
1010 }
1011 
1012 /*
1013  * Read the next block from the tape.
1014  * Check to see if it is one of several vintage headers.
1015  * If it is an old style header, convert it to a new style header.
1016  * If it is not any valid header, return an error.
1017  */
1018 static int
1019 gethead(buf)
1020 	struct s_spcl *buf;
1021 {
1022 	long i;
1023 	union {
1024 		quad_t	qval;
1025 		int32_t	val[2];
1026 	} qcvt;
1027 	union u_ospcl {
1028 		char dummy[TP_BSIZE];
1029 		struct	s_ospcl {
1030 			int32_t	c_type;
1031 			int32_t	c_date;
1032 			int32_t	c_ddate;
1033 			int32_t	c_volume;
1034 			int32_t	c_tapea;
1035 			u_short	c_inumber;
1036 			int32_t	c_magic;
1037 			int32_t	c_checksum;
1038 			struct odinode {
1039 				unsigned short odi_mode;
1040 				u_short	odi_nlink;
1041 				u_short	odi_uid;
1042 				u_short	odi_gid;
1043 				int32_t	odi_size;
1044 				int32_t	odi_rdev;
1045 				char	odi_addr[36];
1046 				int32_t	odi_atime;
1047 				int32_t	odi_mtime;
1048 				int32_t	odi_ctime;
1049 			} c_dinode;
1050 			int32_t	c_count;
1051 			char	c_addr[256];
1052 		} s_ospcl;
1053 	} u_ospcl;
1054 
1055 	if (!cvtflag) {
1056 		readtape((char *)buf);
1057 		if (buf->c_magic != NFS_MAGIC) {
1058 			if (swabl(buf->c_magic) != NFS_MAGIC)
1059 				return (FAIL);
1060 			if (!Bcvt) {
1061 				vprintf(stdout, "Note: Doing Byte swapping\n");
1062 				Bcvt = 1;
1063 			}
1064 		}
1065 		if (checksum((int *)buf) == FAIL)
1066 			return (FAIL);
1067 		if (Bcvt) {
1068 			swabst((u_char *)"8l4s31l", (u_char *)buf);
1069 			swabst((u_char *)"l",(u_char *) &buf->c_level);
1070 			swabst((u_char *)"2l",(u_char *) &buf->c_flags);
1071 		}
1072 		goto good;
1073 	}
1074 	readtape((char *)(&u_ospcl.s_ospcl));
1075 	memset(buf, 0, (long)TP_BSIZE);
1076 	buf->c_type = u_ospcl.s_ospcl.c_type;
1077 	buf->c_date = u_ospcl.s_ospcl.c_date;
1078 	buf->c_ddate = u_ospcl.s_ospcl.c_ddate;
1079 	buf->c_volume = u_ospcl.s_ospcl.c_volume;
1080 	buf->c_tapea = u_ospcl.s_ospcl.c_tapea;
1081 	buf->c_inumber = u_ospcl.s_ospcl.c_inumber;
1082 	buf->c_checksum = u_ospcl.s_ospcl.c_checksum;
1083 	buf->c_magic = u_ospcl.s_ospcl.c_magic;
1084 	buf->c_dinode.di_mode = u_ospcl.s_ospcl.c_dinode.odi_mode;
1085 	buf->c_dinode.di_nlink = u_ospcl.s_ospcl.c_dinode.odi_nlink;
1086 	buf->c_dinode.di_uid = u_ospcl.s_ospcl.c_dinode.odi_uid;
1087 	buf->c_dinode.di_gid = u_ospcl.s_ospcl.c_dinode.odi_gid;
1088 	buf->c_dinode.di_size = u_ospcl.s_ospcl.c_dinode.odi_size;
1089 	buf->c_dinode.di_rdev = u_ospcl.s_ospcl.c_dinode.odi_rdev;
1090 	buf->c_dinode.di_atime = u_ospcl.s_ospcl.c_dinode.odi_atime;
1091 	buf->c_dinode.di_mtime = u_ospcl.s_ospcl.c_dinode.odi_mtime;
1092 	buf->c_dinode.di_ctime = u_ospcl.s_ospcl.c_dinode.odi_ctime;
1093 	buf->c_count = u_ospcl.s_ospcl.c_count;
1094 	memmove(buf->c_addr, u_ospcl.s_ospcl.c_addr, (long)256);
1095 	if (u_ospcl.s_ospcl.c_magic != OFS_MAGIC ||
1096 	    checksum((int *)(&u_ospcl.s_ospcl)) == FAIL)
1097 		return(FAIL);
1098 	buf->c_magic = NFS_MAGIC;
1099 
1100 good:
1101 	if ((buf->c_dinode.di_size == 0 || buf->c_dinode.di_size > 0xfffffff) &&
1102 	    (buf->c_dinode.di_mode & IFMT) == IFDIR && Qcvt == 0) {
1103 		qcvt.qval = buf->c_dinode.di_size;
1104 		if (qcvt.val[0] || qcvt.val[1]) {
1105 			printf("Note: Doing Quad swapping\n");
1106 			Qcvt = 1;
1107 		}
1108 	}
1109 	if (Qcvt) {
1110 		qcvt.qval = buf->c_dinode.di_size;
1111 		i = qcvt.val[1];
1112 		qcvt.val[1] = qcvt.val[0];
1113 		qcvt.val[0] = i;
1114 		buf->c_dinode.di_size = qcvt.qval;
1115 	}
1116 	readmapflag = 0;
1117 
1118 	switch (buf->c_type) {
1119 
1120 	case TS_CLRI:
1121 	case TS_BITS:
1122 		/*
1123 		 * Have to patch up missing information in bit map headers
1124 		 */
1125 		buf->c_inumber = 0;
1126 		buf->c_dinode.di_size = buf->c_count * TP_BSIZE;
1127 		if (buf->c_count > TP_NINDIR)
1128 			readmapflag = 1;
1129 		else
1130 			for (i = 0; i < buf->c_count; i++)
1131 				buf->c_addr[i]++;
1132 		break;
1133 
1134 	case TS_TAPE:
1135 		if ((buf->c_flags & DR_NEWINODEFMT) == 0)
1136 			oldinofmt = 1;
1137 		/* fall through */
1138 	case TS_END:
1139 		buf->c_inumber = 0;
1140 		break;
1141 
1142 	case TS_INODE:
1143 	case TS_ADDR:
1144 		break;
1145 
1146 	default:
1147 		panic("gethead: unknown inode type %d\n", buf->c_type);
1148 		break;
1149 	}
1150 	/*
1151 	 * If we are restoring a filesystem with old format inodes,
1152 	 * copy the uid/gid to the new location.
1153 	 */
1154 	if (oldinofmt) {
1155 		buf->c_dinode.di_uid = buf->c_dinode.di_ouid;
1156 		buf->c_dinode.di_gid = buf->c_dinode.di_ogid;
1157 	}
1158 	tapeaddr = buf->c_tapea;
1159 	if (dflag)
1160 		accthdr(buf);
1161 	return(GOOD);
1162 }
1163 
1164 /*
1165  * Check that a header is where it belongs and predict the next header
1166  */
1167 static void
1168 accthdr(header)
1169 	struct s_spcl *header;
1170 {
1171 	static ino_t previno = 0x7fffffff;
1172 	static int prevtype;
1173 	static long predict;
1174 	long blks, i;
1175 
1176 	if (header->c_type == TS_TAPE) {
1177 		fprintf(stderr, "Volume header (%s inode format) ",
1178 		    oldinofmt ? "old" : "new");
1179  		if (header->c_firstrec)
1180  			fprintf(stderr, "begins with record %ld",
1181  				header->c_firstrec);
1182  		fprintf(stderr, "\n");
1183 		previno = 0x7fffffff;
1184 		return;
1185 	}
1186 	if (previno == 0x7fffffff)
1187 		goto newcalc;
1188 	switch (prevtype) {
1189 	case TS_BITS:
1190 		fprintf(stderr, "Dumped inodes map header");
1191 		break;
1192 	case TS_CLRI:
1193 		fprintf(stderr, "Used inodes map header");
1194 		break;
1195 	case TS_INODE:
1196 		fprintf(stderr, "File header, ino %d", previno);
1197 		break;
1198 	case TS_ADDR:
1199 		fprintf(stderr, "File continuation header, ino %d", previno);
1200 		break;
1201 	case TS_END:
1202 		fprintf(stderr, "End of tape header");
1203 		break;
1204 	}
1205 	if (predict != blksread - 1)
1206 		fprintf(stderr, "; predicted %ld blocks, got %ld blocks",
1207 			predict, blksread - 1);
1208 	fprintf(stderr, "\n");
1209 newcalc:
1210 	blks = 0;
1211 	if (header->c_type != TS_END)
1212 		for (i = 0; i < header->c_count; i++)
1213 			if (readmapflag || header->c_addr[i] != 0)
1214 				blks++;
1215 	predict = blks;
1216 	blksread = 0;
1217 	prevtype = header->c_type;
1218 	previno = header->c_inumber;
1219 }
1220 
1221 /*
1222  * Find an inode header.
1223  * Complain if had to skip.
1224  */
1225 static void
1226 findinode(header)
1227 	struct s_spcl *header;
1228 {
1229 	static long skipcnt = 0;
1230 	long i;
1231 	char buf[TP_BSIZE];
1232 	int htype;
1233 
1234 	curfile.name = "<name unknown>";
1235 	curfile.action = UNKNOWN;
1236 	curfile.dip = NULL;
1237 	curfile.ino = 0;
1238 	do {
1239 		if (header->c_magic != NFS_MAGIC) {
1240 			skipcnt++;
1241 			while (gethead(header) == FAIL ||
1242 			    _time32_to_time(header->c_date) != dumpdate)
1243 				skipcnt++;
1244 		}
1245 		htype = header->c_type;
1246 		switch (htype) {
1247 
1248 		case TS_ADDR:
1249 			/*
1250 			 * Skip up to the beginning of the next record
1251 			 */
1252 			for (i = 0; i < header->c_count; i++)
1253 				if (header->c_addr[i])
1254 					readtape(buf);
1255 			while (gethead(header) == FAIL ||
1256 			    _time32_to_time(header->c_date) != dumpdate)
1257 				skipcnt++;
1258 			break;
1259 
1260 		case TS_INODE:
1261 			curfile.dip = &header->c_dinode;
1262 			curfile.ino = header->c_inumber;
1263 			break;
1264 
1265 		case TS_END:
1266 			/* If we missed some tapes, get another volume. */
1267 			if (tapesread & (tapesread + 1)) {
1268 				getvol(0);
1269 				continue;
1270 			}
1271 			curfile.ino = maxino;
1272 			break;
1273 
1274 		case TS_CLRI:
1275 			curfile.name = "<file removal list>";
1276 			break;
1277 
1278 		case TS_BITS:
1279 			curfile.name = "<file dump list>";
1280 			break;
1281 
1282 		case TS_TAPE:
1283 			panic("unexpected tape header\n");
1284 			/* NOTREACHED */
1285 
1286 		default:
1287 			panic("unknown tape header type %d\n", spcl.c_type);
1288 			/* NOTREACHED */
1289 
1290 		}
1291 	} while (htype == TS_ADDR);
1292 	if (skipcnt > 0)
1293 		fprintf(stderr, "resync restore, skipped %ld blocks\n",
1294 		    skipcnt);
1295 	skipcnt = 0;
1296 }
1297 
1298 static int
1299 checksum(buf)
1300 	register int *buf;
1301 {
1302 	register int i, j;
1303 
1304 	j = sizeof(union u_spcl) / sizeof(int);
1305 	i = 0;
1306 	if(!Bcvt) {
1307 		do
1308 			i += *buf++;
1309 		while (--j);
1310 	} else {
1311 		/* What happens if we want to read restore tapes
1312 			for a 16bit int machine??? */
1313 		do
1314 			i += swabl(*buf++);
1315 		while (--j);
1316 	}
1317 
1318 	if (i != CHECKSUM) {
1319 		fprintf(stderr, "Checksum error %o, inode %d file %s\n", i,
1320 			curfile.ino, curfile.name);
1321 		return(FAIL);
1322 	}
1323 	return(GOOD);
1324 }
1325 
1326 #ifdef RRESTORE
1327 #if __STDC__
1328 #include <stdarg.h>
1329 #else
1330 #include <varargs.h>
1331 #endif
1332 
1333 void
1334 #if __STDC__
1335 msg(const char *fmt, ...)
1336 #else
1337 msg(fmt, va_alist)
1338 	char *fmt;
1339 	va_dcl
1340 #endif
1341 {
1342 	va_list ap;
1343 #if __STDC__
1344 	va_start(ap, fmt);
1345 #else
1346 	va_start(ap);
1347 #endif
1348 	(void)vfprintf(stderr, fmt, ap);
1349 	va_end(ap);
1350 }
1351 #endif /* RRESTORE */
1352 
1353 static u_char *
1354 swabshort(sp, n)
1355 	register u_char *sp;
1356 	register int n;
1357 {
1358 	char c;
1359 
1360 	while (--n >= 0) {
1361 		c = sp[0]; sp[0] = sp[1]; sp[1] = c;
1362 		sp += 2;
1363 	}
1364 	return (sp);
1365 }
1366 
1367 static u_char *
1368 swablong(sp, n)
1369 	register u_char *sp;
1370 	register int n;
1371 {
1372 	char c;
1373 
1374 	while (--n >= 0) {
1375 		c = sp[0]; sp[0] = sp[3]; sp[3] = c;
1376 		c = sp[2]; sp[2] = sp[1]; sp[1] = c;
1377 		sp += 4;
1378 	}
1379 	return (sp);
1380 }
1381 
1382 void
1383 swabst(cp, sp)
1384 	register u_char *cp, *sp;
1385 {
1386 	int n = 0;
1387 
1388 	while (*cp) {
1389 		switch (*cp) {
1390 		case '0': case '1': case '2': case '3': case '4':
1391 		case '5': case '6': case '7': case '8': case '9':
1392 			n = (n * 10) + (*cp++ - '0');
1393 			continue;
1394 
1395 		case 's': case 'w': case 'h':
1396 			if (n == 0)
1397 				n = 1;
1398 			sp = swabshort(sp, n);
1399 			break;
1400 
1401 		case 'l':
1402 			if (n == 0)
1403 				n = 1;
1404 			sp = swablong(sp, n);
1405 			break;
1406 
1407 		default: /* Any other character, like 'b' counts as byte. */
1408 			if (n == 0)
1409 				n = 1;
1410 			sp += n;
1411 			break;
1412 		}
1413 		cp++;
1414 		n = 0;
1415 	}
1416 }
1417 
1418 static u_long
1419 swabl(x)
1420 	u_long x;
1421 {
1422 	swabst((u_char *)"l", (u_char *)&x);
1423 	return (x);
1424 }
1425