xref: /freebsd/sbin/dump/main.c (revision 41466b50c1d5bfd1cf6adaae547a579a75d7c04e)
1 /*-
2  * Copyright (c) 1980, 1991, 1993, 1994
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) 1980, 1991, 1993, 1994\n\
37 	The Regents of the University of California.  All rights reserved.\n";
38 #endif /* not lint */
39 
40 #ifndef lint
41 #if 0
42 static char sccsid[] = "@(#)main.c	8.6 (Berkeley) 5/1/95";
43 #endif
44 static const char rcsid[] =
45   "$FreeBSD$";
46 #endif /* not lint */
47 
48 #include <sys/param.h>
49 #include <sys/stat.h>
50 #include <sys/time.h>
51 #ifdef sunos
52 #include <sys/vnode.h>
53 
54 #include <ufs/inode.h>
55 #include <ufs/fs.h>
56 #else
57 #include <ufs/ufs/dinode.h>
58 #include <ufs/ffs/fs.h>
59 #endif
60 
61 #include <protocols/dumprestore.h>
62 
63 #include <ctype.h>
64 #include <err.h>
65 #include <fcntl.h>
66 #include <fstab.h>
67 #include <signal.h>
68 #include <stdio.h>
69 #include <stdlib.h>
70 #include <string.h>
71 #include <unistd.h>
72 
73 #include "dump.h"
74 #include "pathnames.h"
75 
76 #ifndef SBOFF
77 #define SBOFF (SBLOCK * DEV_BSIZE)
78 #endif
79 
80 int	notify = 0;	/* notify operator flag */
81 int	blockswritten = 0;	/* number of blocks written on current tape */
82 int	tapeno = 0;	/* current tape number */
83 int	density = 0;	/* density in bytes/0.1" " <- this is for hilit19 */
84 int	ntrec = NTREC;	/* # tape blocks in each tape record */
85 int	cartridge = 0;	/* Assume non-cartridge tape */
86 int	dokerberos = 0;	/* Use Kerberos authentication */
87 long	dev_bsize = 1;	/* recalculated below */
88 long	blocksperfile;	/* output blocks per file */
89 char	*host = NULL;	/* remote host (if any) */
90 
91 static long numarg __P((char *, long, long));
92 static void obsolete __P((int *, char **[]));
93 static void usage __P((void));
94 
95 int
96 main(argc, argv)
97 	int argc;
98 	char *argv[];
99 {
100 	register ino_t ino;
101 	register int dirty;
102 	register struct dinode *dp;
103 	register struct	fstab *dt;
104 	register char *map;
105 	register int ch;
106 	int i, anydirskipped, bflag = 0, Tflag = 0, honorlevel = 1;
107 	ino_t maxino;
108 	char *tmsg;
109 	time_t t;
110 
111 	spcl.c_date = time_to_time32(time(NULL));
112 
113 	tsize = 0;	/* Default later, based on 'c' option for cart tapes */
114 	if ((tape = getenv("TAPE")) == NULL)
115 		tape = _PATH_DEFTAPE;
116 	dumpdates = _PATH_DUMPDATES;
117 	temp = _PATH_DTMP;
118 	if (TP_BSIZE / DEV_BSIZE == 0 || TP_BSIZE % DEV_BSIZE != 0)
119 		quit("TP_BSIZE must be a multiple of DEV_BSIZE\n");
120 	level = '0';
121 
122 	if (argc < 2)
123 		usage();
124 
125 	obsolete(&argc, &argv);
126 #ifdef KERBEROS
127 #define optstring "0123456789aB:b:cd:f:h:kns:T:uWwD:"
128 #else
129 #define optstring "0123456789aB:b:cd:f:h:ns:T:uWwD:"
130 #endif
131 	while ((ch = getopt(argc, argv, optstring)) != -1)
132 #undef optstring
133 		switch (ch) {
134 		/* dump level */
135 		case '0': case '1': case '2': case '3': case '4':
136 		case '5': case '6': case '7': case '8': case '9':
137 			level = ch;
138 			break;
139 
140 		case 'a':		/* `auto-size', Write to EOM. */
141 			unlimited = 1;
142 			break;
143 
144 		case 'B':		/* blocks per output file */
145 			blocksperfile = numarg("number of blocks per file",
146 			    1L, 0L);
147 			break;
148 
149 		case 'b':		/* blocks per tape write */
150 			ntrec = numarg("number of blocks per write",
151 			    1L, 1000L);
152 			break;
153 
154 		case 'c':		/* Tape is cart. not 9-track */
155 			cartridge = 1;
156 			break;
157 
158 		case 'd':		/* density, in bits per inch */
159 			density = numarg("density", 10L, 327670L) / 10;
160 			if (density >= 625 && !bflag)
161 				ntrec = HIGHDENSITYTREC;
162 			break;
163 
164 		case 'f':		/* output file */
165 			tape = optarg;
166 			break;
167 
168 		case 'D':
169 			dumpdates = optarg;
170 			break;
171 
172 		case 'h':
173 			honorlevel = numarg("honor level", 0L, 10L);
174 			break;
175 
176 #ifdef KERBEROS
177 		case 'k':
178 			dokerberos = 1;
179 			break;
180 #endif
181 
182 		case 'n':		/* notify operators */
183 			notify = 1;
184 			break;
185 
186 		case 's':		/* tape size, feet */
187 			tsize = numarg("tape size", 1L, 0L) * 12 * 10;
188 			break;
189 
190 		case 'T':		/* time of last dump */
191 			spcl.c_ddate = unctime(optarg);
192 			if (spcl.c_ddate < 0) {
193 				(void)fprintf(stderr, "bad time \"%s\"\n",
194 				    optarg);
195 				exit(X_STARTUP);
196 			}
197 			Tflag = 1;
198 			lastlevel = '?';
199 			break;
200 
201 		case 'u':		/* update /etc/dumpdates */
202 			uflag = 1;
203 			break;
204 
205 		case 'W':		/* what to do */
206 		case 'w':
207 			lastdump(ch);
208 			exit(X_FINOK);	/* do nothing else */
209 
210 		default:
211 			usage();
212 		}
213 	argc -= optind;
214 	argv += optind;
215 
216 	if (argc < 1) {
217 		(void)fprintf(stderr, "Must specify disk or filesystem\n");
218 		exit(X_STARTUP);
219 	}
220 	disk = *argv++;
221 	argc--;
222 	if (argc >= 1) {
223 		(void)fprintf(stderr, "Unknown arguments to dump:");
224 		while (argc--)
225 			(void)fprintf(stderr, " %s", *argv++);
226 		(void)fprintf(stderr, "\n");
227 		exit(X_STARTUP);
228 	}
229 	if (Tflag && uflag) {
230 	        (void)fprintf(stderr,
231 		    "You cannot use the T and u flags together.\n");
232 		exit(X_STARTUP);
233 	}
234 	if (strcmp(tape, "-") == 0) {
235 		pipeout++;
236 		tape = "standard output";
237 	}
238 
239 	if (blocksperfile)
240 		blocksperfile = blocksperfile / ntrec * ntrec; /* round down */
241 	else if (!unlimited) {
242 		/*
243 		 * Determine how to default tape size and density
244 		 *
245 		 *         	density				tape size
246 		 * 9-track	1600 bpi (160 bytes/.1")	2300 ft.
247 		 * 9-track	6250 bpi (625 bytes/.1")	2300 ft.
248 		 * cartridge	8000 bpi (100 bytes/.1")	1700 ft.
249 		 *						(450*4 - slop)
250 		 * hilit19 hits again: "
251 		 */
252 		if (density == 0)
253 			density = cartridge ? 100 : 160;
254 		if (tsize == 0)
255 			tsize = cartridge ? 1700L*120L : 2300L*120L;
256 	}
257 
258 	if (strchr(tape, ':')) {
259 		host = tape;
260 		tape = strchr(host, ':');
261 		*tape++ = '\0';
262 #ifdef RDUMP
263 		if (index(tape, '\n')) {
264 		    (void)fprintf(stderr, "invalid characters in tape\n");
265 		    exit(X_STARTUP);
266 		}
267 		if (rmthost(host) == 0)
268 			exit(X_STARTUP);
269 #else
270 		(void)fprintf(stderr, "remote dump not enabled\n");
271 		exit(X_STARTUP);
272 #endif
273 	}
274 	(void)setuid(getuid()); /* rmthost() is the only reason to be setuid */
275 
276 	if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
277 		signal(SIGHUP, sig);
278 	if (signal(SIGTRAP, SIG_IGN) != SIG_IGN)
279 		signal(SIGTRAP, sig);
280 	if (signal(SIGFPE, SIG_IGN) != SIG_IGN)
281 		signal(SIGFPE, sig);
282 	if (signal(SIGBUS, SIG_IGN) != SIG_IGN)
283 		signal(SIGBUS, sig);
284 	if (signal(SIGSEGV, SIG_IGN) != SIG_IGN)
285 		signal(SIGSEGV, sig);
286 	if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
287 		signal(SIGTERM, sig);
288 	if (signal(SIGINT, interrupt) == SIG_IGN)
289 		signal(SIGINT, SIG_IGN);
290 
291 	getfstab();		/* /etc/fstab snarfed */
292 	/*
293 	 *	disk can be either the full special file name,
294 	 *	the suffix of the special file name,
295 	 *	the special name missing the leading '/',
296 	 *	the file system name with or without the leading '/'.
297 	 */
298 	dt = fstabsearch(disk);
299 	if (dt != NULL) {
300 		disk = rawname(dt->fs_spec);
301 		(void)strncpy(spcl.c_dev, dt->fs_spec, NAMELEN);
302 		(void)strncpy(spcl.c_filesys, dt->fs_file, NAMELEN);
303 	} else {
304 		(void)strncpy(spcl.c_dev, disk, NAMELEN);
305 		(void)strncpy(spcl.c_filesys, "an unlisted file system",
306 		    NAMELEN);
307 	}
308 	spcl.c_dev[NAMELEN-1]='\0';
309 	spcl.c_filesys[NAMELEN-1]='\0';
310 	(void)strcpy(spcl.c_label, "none");
311 	(void)gethostname(spcl.c_host, NAMELEN);
312 	spcl.c_level = level - '0';
313 	spcl.c_type = TS_TAPE;
314 	if (!Tflag)
315 	        getdumptime();		/* /etc/dumpdates snarfed */
316 
317 	if (spcl.c_date == 0) {
318 		tmsg = "the epoch\n";
319 	} else {
320 		time_t t = time32_to_time(spcl.c_date);
321 		tmsg = ctime(&t);
322 	}
323 	msg("Date of this level %c dump: %s", level, tmsg);
324 	if (spcl.c_ddate == 0) {
325 		tmsg = "the epoch\n";
326 	} else {
327 		time_t t = time32_to_time(spcl.c_ddate);
328 		tmsg = ctime(&t);
329 	}
330  	msg("Date of last level %c dump: %s", lastlevel, tmsg);
331 	msg("Dumping %s ", disk);
332 	if (dt != NULL)
333 		msgtail("(%s) ", dt->fs_file);
334 	if (host)
335 		msgtail("to %s on host %s\n", tape, host);
336 	else
337 		msgtail("to %s\n", tape);
338 
339 	if ((diskfd = open(disk, O_RDONLY)) < 0) {
340 		msg("Cannot open %s\n", disk);
341 		exit(X_STARTUP);
342 	}
343 	sync();
344 	sblock = (struct fs *)sblock_buf;
345 	bread(SBOFF, (char *) sblock, SBSIZE);
346 	if (sblock->fs_magic != FS_MAGIC)
347 		quit("bad sblock magic number\n");
348 	dev_bsize = sblock->fs_fsize / fsbtodb(sblock, 1);
349 	dev_bshift = ffs(dev_bsize) - 1;
350 	if (dev_bsize != (1 << dev_bshift))
351 		quit("dev_bsize (%d) is not a power of 2", dev_bsize);
352 	tp_bshift = ffs(TP_BSIZE) - 1;
353 	if (TP_BSIZE != (1 << tp_bshift))
354 		quit("TP_BSIZE (%d) is not a power of 2", TP_BSIZE);
355 #ifdef FS_44INODEFMT
356 	if (sblock->fs_inodefmt >= FS_44INODEFMT)
357 		spcl.c_flags |= DR_NEWINODEFMT;
358 #endif
359 	maxino = sblock->fs_ipg * sblock->fs_ncg;
360 	mapsize = roundup(howmany(maxino, NBBY), TP_BSIZE);
361 	usedinomap = (char *)calloc((unsigned) mapsize, sizeof(char));
362 	dumpdirmap = (char *)calloc((unsigned) mapsize, sizeof(char));
363 	dumpinomap = (char *)calloc((unsigned) mapsize, sizeof(char));
364 	tapesize = 3 * (howmany(mapsize * sizeof(char), TP_BSIZE) + 1);
365 
366 	nonodump = spcl.c_level < honorlevel;
367 
368 	msg("mapping (Pass I) [regular files]\n");
369 	anydirskipped = mapfiles(maxino, &tapesize);
370 
371 	msg("mapping (Pass II) [directories]\n");
372 	while (anydirskipped) {
373 		anydirskipped = mapdirs(maxino, &tapesize);
374 	}
375 
376 	if (pipeout || unlimited) {
377 		tapesize += 10;	/* 10 trailer blocks */
378 		msg("estimated %ld tape blocks.\n", tapesize);
379 	} else {
380 		double fetapes;
381 
382 		if (blocksperfile)
383 			fetapes = (double) tapesize / blocksperfile;
384 		else if (cartridge) {
385 			/* Estimate number of tapes, assuming streaming stops at
386 			   the end of each block written, and not in mid-block.
387 			   Assume no erroneous blocks; this can be compensated
388 			   for with an artificially low tape size. */
389 			fetapes =
390 			(	  (double) tapesize	/* blocks */
391 				* TP_BSIZE	/* bytes/block */
392 				* (1.0/density)	/* 0.1" / byte " */
393 			  +
394 				  (double) tapesize	/* blocks */
395 				* (1.0/ntrec)	/* streaming-stops per block */
396 				* 15.48		/* 0.1" / streaming-stop " */
397 			) * (1.0 / tsize );	/* tape / 0.1" " */
398 		} else {
399 			/* Estimate number of tapes, for old fashioned 9-track
400 			   tape */
401 			int tenthsperirg = (density == 625) ? 3 : 7;
402 			fetapes =
403 			(	  (double) tapesize	/* blocks */
404 				* TP_BSIZE	/* bytes / block */
405 				* (1.0/density)	/* 0.1" / byte " */
406 			  +
407 				  (double) tapesize	/* blocks */
408 				* (1.0/ntrec)	/* IRG's / block */
409 				* tenthsperirg	/* 0.1" / IRG " */
410 			) * (1.0 / tsize );	/* tape / 0.1" " */
411 		}
412 		etapes = fetapes;		/* truncating assignment */
413 		etapes++;
414 		/* count the dumped inodes map on each additional tape */
415 		tapesize += (etapes - 1) *
416 			(howmany(mapsize * sizeof(char), TP_BSIZE) + 1);
417 		tapesize += etapes + 10;	/* headers + 10 trailer blks */
418 		msg("estimated %ld tape blocks on %3.2f tape(s).\n",
419 		    tapesize, fetapes);
420 	}
421 
422 	/*
423 	 * Allocate tape buffer.
424 	 */
425 	if (!alloctape())
426 		quit(
427 	"can't allocate tape buffers - try a smaller blocking factor.\n");
428 
429 	startnewtape(1);
430 	(void)time((time_t *)&(tstart_writing));
431 	dumpmap(usedinomap, TS_CLRI, maxino - 1);
432 
433 	msg("dumping (Pass III) [directories]\n");
434 	dirty = 0;		/* XXX just to get gcc to shut up */
435 	for (map = dumpdirmap, ino = 1; ino < maxino; ino++) {
436 		if (((ino - 1) % NBBY) == 0)	/* map is offset by 1 */
437 			dirty = *map++;
438 		else
439 			dirty >>= 1;
440 		if ((dirty & 1) == 0)
441 			continue;
442 		/*
443 		 * Skip directory inodes deleted and maybe reallocated
444 		 */
445 		dp = getino(ino);
446 		if ((dp->di_mode & IFMT) != IFDIR)
447 			continue;
448 		(void)dumpino(dp, ino);
449 	}
450 
451 	msg("dumping (Pass IV) [regular files]\n");
452 	for (map = dumpinomap, ino = 1; ino < maxino; ino++) {
453 		int mode;
454 
455 		if (((ino - 1) % NBBY) == 0)	/* map is offset by 1 */
456 			dirty = *map++;
457 		else
458 			dirty >>= 1;
459 		if ((dirty & 1) == 0)
460 			continue;
461 		/*
462 		 * Skip inodes deleted and reallocated as directories.
463 		 */
464 		dp = getino(ino);
465 		mode = dp->di_mode & IFMT;
466 		if (mode == IFDIR)
467 			continue;
468 		(void)dumpino(dp, ino);
469 	}
470 
471 	(void)time((time_t *)&(tend_writing));
472 	spcl.c_type = TS_END;
473 	for (i = 0; i < ntrec; i++)
474 		writeheader(maxino - 1);
475 	if (pipeout)
476 		msg("DUMP: %ld tape blocks\n", spcl.c_tapea);
477 	else
478 		msg("DUMP: %ld tape blocks on %d volume%s\n",
479 		    spcl.c_tapea, spcl.c_volume,
480 		    (spcl.c_volume == 1) ? "" : "s");
481 
482 	/* report dump performance, avoid division through zero */
483 	if (tend_writing - tstart_writing == 0)
484 		msg("finished in less than a second\n");
485 	else
486 		msg("finished in %d seconds, throughput %d KBytes/sec\n",
487 		    tend_writing - tstart_writing,
488 		    spcl.c_tapea / (tend_writing - tstart_writing));
489 
490 	putdumptime();
491 	trewind();
492 	broadcast("DUMP IS DONE!\a\a\n");
493 	msg("DUMP IS DONE\n");
494 	Exit(X_FINOK);
495 	/* NOTREACHED */
496 }
497 
498 static void
499 usage()
500 {
501 	fprintf(stderr,
502 		"usage: dump [-0123456789ac"
503 #ifdef KERBEROS
504 		"k"
505 #endif
506 		"nu] [-B records] [-b blocksize] [-D dumpdates]\n"
507 		"            [-d density] [-f file ] [-h level] [-s feet] "
508 		"[-T date] filesystem\n"
509 		"       dump [-W | -w]\n");
510 	exit(X_STARTUP);
511 }
512 
513 /*
514  * Pick up a numeric argument.  It must be nonnegative and in the given
515  * range (except that a vmax of 0 means unlimited).
516  */
517 static long
518 numarg(meaning, vmin, vmax)
519 	char *meaning;
520 	long vmin, vmax;
521 {
522 	char *p;
523 	long val;
524 
525 	val = strtol(optarg, &p, 10);
526 	if (*p)
527 		errx(1, "illegal %s -- %s", meaning, optarg);
528 	if (val < vmin || (vmax && val > vmax))
529 		errx(1, "%s must be between %ld and %ld", meaning, vmin, vmax);
530 	return (val);
531 }
532 
533 void
534 sig(signo)
535 	int signo;
536 {
537 	switch(signo) {
538 	case SIGALRM:
539 	case SIGBUS:
540 	case SIGFPE:
541 	case SIGHUP:
542 	case SIGTERM:
543 	case SIGTRAP:
544 		if (pipeout)
545 			quit("Signal on pipe: cannot recover\n");
546 		msg("Rewriting attempted as response to unknown signal.\n");
547 		(void)fflush(stderr);
548 		(void)fflush(stdout);
549 		close_rewind();
550 		exit(X_REWRITE);
551 		/* NOTREACHED */
552 	case SIGSEGV:
553 		msg("SIGSEGV: ABORTING!\n");
554 		(void)signal(SIGSEGV, SIG_DFL);
555 		(void)kill(0, SIGSEGV);
556 		/* NOTREACHED */
557 	}
558 }
559 
560 char *
561 rawname(cp)
562 	char *cp;
563 {
564 	static char rawbuf[MAXPATHLEN];
565 	char *dp;
566 	struct stat sb;
567 
568 	if (stat(cp, &sb) == 0) {
569 		/*
570 		 * If the name already refers to a raw device, return
571 		 * it immediately without tampering.
572 		 */
573 		if ((sb.st_mode & S_IFMT) == S_IFCHR)
574 			return (cp);
575 	}
576 
577 	dp = strrchr(cp, '/');
578 
579 	if (dp == NULL)
580 		return (NULL);
581 	*dp = '\0';
582 	(void)strncpy(rawbuf, cp, MAXPATHLEN - 1);
583 	rawbuf[MAXPATHLEN-1] = '\0';
584 	*dp = '/';
585 	(void)strncat(rawbuf, "/r", MAXPATHLEN - 1 - strlen(rawbuf));
586 	(void)strncat(rawbuf, dp + 1, MAXPATHLEN - 1 - strlen(rawbuf));
587 	return (rawbuf);
588 }
589 
590 /*
591  * obsolete --
592  *	Change set of key letters and ordered arguments into something
593  *	getopt(3) will like.
594  */
595 static void
596 obsolete(argcp, argvp)
597 	int *argcp;
598 	char **argvp[];
599 {
600 	int argc, flags;
601 	char *ap, **argv, *flagsp, **nargv, *p;
602 
603 	/* Setup. */
604 	argv = *argvp;
605 	argc = *argcp;
606 
607 	/* Return if no arguments or first argument has leading dash. */
608 	ap = argv[1];
609 	if (argc == 1 || *ap == '-')
610 		return;
611 
612 	/* Allocate space for new arguments. */
613 	if ((*argvp = nargv = malloc((argc + 1) * sizeof(char *))) == NULL ||
614 	    (p = flagsp = malloc(strlen(ap) + 2)) == NULL)
615 		err(1, NULL);
616 
617 	*nargv++ = *argv;
618 	argv += 2;
619 
620 	for (flags = 0; *ap; ++ap) {
621 		switch (*ap) {
622 		case 'B':
623 		case 'b':
624 		case 'd':
625 		case 'f':
626 		case 'D':
627 		case 'h':
628 		case 's':
629 		case 'T':
630 			if (*argv == NULL) {
631 				warnx("option requires an argument -- %c", *ap);
632 				usage();
633 			}
634 			if ((nargv[0] = malloc(strlen(*argv) + 2 + 1)) == NULL)
635 				err(1, NULL);
636 			nargv[0][0] = '-';
637 			nargv[0][1] = *ap;
638 			(void)strcpy(&nargv[0][2], *argv);
639 			++argv;
640 			++nargv;
641 			break;
642 		default:
643 			if (!flags) {
644 				*p++ = '-';
645 				flags = 1;
646 			}
647 			*p++ = *ap;
648 			break;
649 		}
650 	}
651 
652 	/* Terminate flags. */
653 	if (flags) {
654 		*p = '\0';
655 		*nargv++ = flagsp;
656 	}
657 
658 	/* Copy remaining arguments. */
659 	while ((*nargv++ = *argv++));
660 
661 	/* Update argument count. */
662 	*argcp = nargv - *argvp - 1;
663 }
664