xref: /freebsd/sbin/swapon/swapon.c (revision 273c26a3c3bea87a241d6879abd4f991db180bf0)
1 /*-
2  * Copyright (c) 1980, 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  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #if 0
31 #ifndef lint
32 static const char copyright[] =
33 "@(#) Copyright (c) 1980, 1993\n\
34 	The Regents of the University of California.  All rights reserved.\n";
35 #endif /* not lint */
36 
37 #ifndef lint
38 static char sccsid[] = "@(#)swapon.c	8.1 (Berkeley) 6/5/93";
39 #endif /* not lint */
40 #endif
41 #include <sys/cdefs.h>
42 __FBSDID("$FreeBSD$");
43 
44 #include <sys/param.h>
45 #include <sys/types.h>
46 #include <sys/mdioctl.h>
47 #include <sys/stat.h>
48 #include <sys/sysctl.h>
49 #include <sys/wait.h>
50 #include <vm/vm_param.h>
51 
52 #include <err.h>
53 #include <errno.h>
54 #include <fcntl.h>
55 #include <fnmatch.h>
56 #include <fstab.h>
57 #include <libgen.h>
58 #include <libutil.h>
59 #include <limits.h>
60 #include <paths.h>
61 #include <stdarg.h>
62 #include <stdio.h>
63 #include <stdlib.h>
64 #include <string.h>
65 #include <unistd.h>
66 
67 static void usage(void);
68 static const char *swap_on_off(const char *, int, char *);
69 static const char *swap_on_off_gbde(const char *, int);
70 static const char *swap_on_off_geli(const char *, char *, int);
71 static const char *swap_on_off_md(const char *, char *, int);
72 static const char *swap_on_off_sfile(const char *, int);
73 static void swaplist(int, int, int);
74 static int run_cmd(int *, const char *, ...) __printflike(2, 3);
75 
76 static enum { SWAPON, SWAPOFF, SWAPCTL } orig_prog, which_prog = SWAPCTL;
77 
78 static int qflag;
79 
80 int
81 main(int argc, char **argv)
82 {
83 	struct fstab *fsp;
84 	const char *swfile;
85 	char *ptr;
86 	int ret, ch, doall;
87 	int sflag, lflag, late, hflag;
88 	const char *etc_fstab;
89 
90 	sflag = lflag = late = hflag = 0;
91 	if ((ptr = strrchr(argv[0], '/')) == NULL)
92 		ptr = argv[0];
93 	if (strstr(ptr, "swapon") != NULL)
94 		which_prog = SWAPON;
95 	else if (strstr(ptr, "swapoff") != NULL)
96 		which_prog = SWAPOFF;
97 	orig_prog = which_prog;
98 
99 	doall = 0;
100 	etc_fstab = NULL;
101 	while ((ch = getopt(argc, argv, "AadghklLmqsUF:")) != -1) {
102 		switch(ch) {
103 		case 'A':
104 			if (which_prog == SWAPCTL) {
105 				doall = 1;
106 				which_prog = SWAPON;
107 			} else
108 				usage();
109 			break;
110 		case 'a':
111 			if (which_prog == SWAPON || which_prog == SWAPOFF)
112 				doall = 1;
113 			else
114 				which_prog = SWAPON;
115 			break;
116 		case 'd':
117 			if (which_prog == SWAPCTL)
118 				which_prog = SWAPOFF;
119 			else
120 				usage();
121 			break;
122 		case 'g':
123 			hflag = 'G';
124 			break;
125 		case 'h':
126 			hflag = 'H';
127 			break;
128 		case 'k':
129 			hflag = 'K';
130 			break;
131 		case 'l':
132 			lflag = 1;
133 			break;
134 		case 'L':
135 			late = 1;
136 			break;
137 		case 'm':
138 			hflag = 'M';
139 			break;
140 		case 'q':
141 			if (which_prog == SWAPON || which_prog == SWAPOFF)
142 				qflag = 1;
143 			break;
144 		case 's':
145 			sflag = 1;
146 			break;
147 		case 'U':
148 			if (which_prog == SWAPCTL) {
149 				doall = 1;
150 				which_prog = SWAPOFF;
151 			} else
152 				usage();
153 			break;
154 		case 'F':
155 			etc_fstab = optarg;
156 			break;
157 		case '?':
158 		default:
159 			usage();
160 		}
161 	}
162 	argv += optind;
163 
164 	ret = 0;
165 	swfile = NULL;
166 	if (etc_fstab != NULL)
167 		setfstab(etc_fstab);
168 	if (which_prog == SWAPON || which_prog == SWAPOFF) {
169 		if (doall) {
170 			while ((fsp = getfsent()) != NULL) {
171 				if (strcmp(fsp->fs_type, FSTAB_SW) != 0)
172 					continue;
173 				if (strstr(fsp->fs_mntops, "noauto") != NULL)
174 					continue;
175 				if (which_prog != SWAPOFF &&
176 				    strstr(fsp->fs_mntops, "late") &&
177 				    late == 0)
178 					continue;
179 				swfile = swap_on_off(fsp->fs_spec, 1,
180 				    fsp->fs_mntops);
181 				if (swfile == NULL) {
182 					ret = 1;
183 					continue;
184 				}
185 				if (qflag == 0) {
186 					printf("%s: %sing %s as swap device\n",
187 					    getprogname(),
188 					    (which_prog == SWAPOFF) ?
189 					    "remov" : "add", swfile);
190 				}
191 			}
192 		} else if (*argv == NULL)
193 			usage();
194 		for (; *argv; ++argv) {
195 			swfile = swap_on_off(*argv, 0, NULL);
196 			if (swfile == NULL) {
197 				ret = 1;
198 				continue;
199 			}
200 			if (orig_prog == SWAPCTL) {
201 				printf("%s: %sing %s as swap device\n",
202 				    getprogname(),
203 				    (which_prog == SWAPOFF) ? "remov" : "add",
204 				    swfile);
205 			}
206 		}
207 	} else {
208 		if (lflag || sflag)
209 			swaplist(lflag, sflag, hflag);
210 		else
211 			usage();
212 	}
213 	exit(ret);
214 }
215 
216 static const char *
217 swap_on_off(const char *name, int doingall, char *mntops)
218 {
219 	char *base, *basebuf;
220 
221 	/* Swap on vnode-backed md(4) device. */
222 	if (mntops != NULL &&
223 	    (fnmatch(_PATH_DEV MD_NAME "[0-9]*", name, 0) == 0 ||
224 	     fnmatch(MD_NAME "[0-9]*", name, 0) == 0 ||
225 	     strncmp(_PATH_DEV MD_NAME, name,
226 		sizeof(_PATH_DEV) + sizeof(MD_NAME)) == 0 ||
227 	     strncmp(MD_NAME, name, sizeof(MD_NAME)) == 0))
228 		return (swap_on_off_md(name, mntops, doingall));
229 
230 	basebuf = strdup(name);
231 	base = basename(basebuf);
232 
233 	/* Swap on encrypted device by GEOM_BDE. */
234 	if (fnmatch("*.bde", base, 0) == 0) {
235 		free(basebuf);
236 		return (swap_on_off_gbde(name, doingall));
237 	}
238 
239 	/* Swap on encrypted device by GEOM_ELI. */
240 	if (fnmatch("*.eli", base, 0) == 0) {
241 		free(basebuf);
242 		return (swap_on_off_geli(name, mntops, doingall));
243 	}
244 
245 	/* Swap on special file. */
246 	free(basebuf);
247 	return (swap_on_off_sfile(name, doingall));
248 }
249 
250 /* Strip off .bde or .eli suffix from swap device name */
251 static char *
252 swap_basename(const char *name)
253 {
254 	char *dname, *p;
255 
256 	dname = strdup(name);
257 	p = strrchr(dname, '.');
258 	/* assert(p != NULL); */
259 	*p = '\0';
260 
261 	return (dname);
262 }
263 
264 static const char *
265 swap_on_off_gbde(const char *name, int doingall)
266 {
267 	const char *ret;
268 	char pass[64 * 2 + 1];
269 	unsigned char bpass[64];
270 	char *dname;
271 	int i, error;
272 
273 	dname = swap_basename(name);
274 	if (dname == NULL)
275 		return (NULL);
276 
277 	if (which_prog == SWAPON) {
278 		arc4random_buf(bpass, sizeof(bpass));
279 		for (i = 0; i < (int)sizeof(bpass); i++)
280 			sprintf(&pass[2 * i], "%02x", bpass[i]);
281 		pass[sizeof(pass) - 1] = '\0';
282 
283 		error = run_cmd(NULL, "%s init %s -P %s", _PATH_GBDE,
284 		    dname, pass);
285 		if (error) {
286 			/* bde device found.  Ignore it. */
287 			free(dname);
288 			if (qflag == 0)
289 				warnx("%s: Device already in use", name);
290 			return (NULL);
291 		}
292 		error = run_cmd(NULL, "%s attach %s -p %s", _PATH_GBDE,
293 		    dname, pass);
294 		free(dname);
295 		if (error) {
296 			warnx("gbde (attach) error: %s", name);
297 			return (NULL);
298 		}
299 	}
300 
301 	ret = swap_on_off_sfile(name, doingall);
302 
303 	if (which_prog == SWAPOFF) {
304 		error = run_cmd(NULL, "%s detach %s", _PATH_GBDE, dname);
305 		free(dname);
306 		if (error) {
307 			/* bde device not found.  Ignore it. */
308 			if (qflag == 0)
309 				warnx("%s: Device not found", name);
310 			return (NULL);
311 		}
312 	}
313 
314 	return (ret);
315 }
316 
317 /* Build geli(8) arguments from mntops */
318 static char *
319 swap_on_geli_args(const char *mntops)
320 {
321 	const char *aalgo, *ealgo, *keylen_str, *sectorsize_str;
322 	const char *aflag, *eflag, *lflag, *Tflag, *sflag;
323 	char *p, *args, *token, *string, *ops;
324 	int pagesize;
325 	size_t pagesize_len;
326 	u_long ul;
327 
328 	/* Use built-in defaults for geli(8). */
329 	aalgo = ealgo = keylen_str = "";
330 	aflag = eflag = lflag = Tflag = "";
331 
332 	/* We will always specify sectorsize. */
333 	sflag = " -s ";
334 	sectorsize_str = NULL;
335 
336 	if (mntops != NULL) {
337 		string = ops = strdup(mntops);
338 
339 		while ((token = strsep(&string, ",")) != NULL) {
340 			if ((p = strstr(token, "aalgo=")) == token) {
341 				aalgo = p + sizeof("aalgo=") - 1;
342 				aflag = " -a ";
343 			} else if ((p = strstr(token, "ealgo=")) == token) {
344 				ealgo = p + sizeof("ealgo=") - 1;
345 				eflag = " -e ";
346 			} else if ((p = strstr(token, "keylen=")) == token) {
347 				keylen_str = p + sizeof("keylen=") - 1;
348 				errno = 0;
349 				ul = strtoul(keylen_str, &p, 10);
350 				if (errno == 0) {
351 					if (*p != '\0' || ul > INT_MAX)
352 						errno = EINVAL;
353 				}
354 				if (errno) {
355 					warn("Invalid keylen: %s", keylen_str);
356 					free(ops);
357 					return (NULL);
358 				}
359 				lflag = " -l ";
360 			} else if ((p = strstr(token, "sectorsize=")) == token) {
361 				sectorsize_str = p + sizeof("sectorsize=") - 1;
362 				errno = 0;
363 				ul = strtoul(sectorsize_str, &p, 10);
364 				if (errno == 0) {
365 					if (*p != '\0' || ul > INT_MAX)
366 						errno = EINVAL;
367 				}
368 				if (errno) {
369 					warn("Invalid sectorsize: %s",
370 					    sectorsize_str);
371 					free(ops);
372 					return (NULL);
373 				}
374 			} else if ((p = strstr(token, "notrim")) == token) {
375 				Tflag = " -T ";
376 			} else if (strcmp(token, "sw") != 0) {
377 				warnx("Invalid option: %s", token);
378 				free(ops);
379 				return (NULL);
380 			}
381 		}
382 	} else
383 		ops = NULL;
384 
385 	/*
386 	 * If we do not have a sector size at this point, fill in
387 	 * pagesize as sector size.
388 	 */
389 	if (sectorsize_str == NULL) {
390 		/* Use pagesize as default sectorsize. */
391 		pagesize = getpagesize();
392 		pagesize_len = snprintf(NULL, 0, "%d", pagesize) + 1;
393 		p = alloca(pagesize_len);
394 		snprintf(p, pagesize_len, "%d", pagesize);
395 		sectorsize_str = p;
396 	}
397 
398 	(void)asprintf(&args, "%s%s%s%s%s%s%s%s%s -d",
399 	    aflag, aalgo, eflag, ealgo, lflag, keylen_str, Tflag,
400 	    sflag, sectorsize_str);
401 
402 	free(ops);
403 	return (args);
404 }
405 
406 static const char *
407 swap_on_off_geli(const char *name, char *mntops, int doingall)
408 {
409 	struct stat sb;
410 	char *dname, *args;
411 	int error;
412 
413 	error = stat(name, &sb);
414 
415 	if (which_prog == SWAPON) do {
416 		/* Skip if the .eli device already exists. */
417 		if (error == 0)
418 			break;
419 
420 		args = swap_on_geli_args(mntops);
421 		if (args == NULL)
422 			return (NULL);
423 
424 		dname = swap_basename(name);
425 		if (dname == NULL) {
426 			free(args);
427 			return (NULL);
428 		}
429 
430 		error = run_cmd(NULL, "%s onetime%s %s", _PATH_GELI, args,
431 		    dname);
432 
433 		free(dname);
434 		free(args);
435 
436 		if (error) {
437 			/* error occurred during creation. */
438 			if (qflag == 0)
439 				warnx("%s: Invalid parameters", name);
440 			return (NULL);
441 		}
442 	} while (0);
443 
444 	return (swap_on_off_sfile(name, doingall));
445 }
446 
447 static const char *
448 swap_on_off_md(const char *name, char *mntops, int doingall)
449 {
450 	FILE *sfd;
451 	int fd, mdunit, error;
452 	const char *ret;
453 	static char mdpath[PATH_MAX], linebuf[PATH_MAX];
454 	char *p, *vnodefile;
455 	size_t linelen;
456 	u_long ul;
457 
458 	fd = -1;
459 	sfd = NULL;
460 	if (strlen(name) == (sizeof(MD_NAME) - 1))
461 		mdunit = -1;
462 	else {
463 		errno = 0;
464 		ul = strtoul(name + 2, &p, 10);
465 		if (errno == 0) {
466 			if (*p != '\0' || ul > INT_MAX)
467 				errno = EINVAL;
468 		}
469 		if (errno) {
470 			warn("Bad device unit: %s", name);
471 			return (NULL);
472 		}
473 		mdunit = (int)ul;
474 	}
475 
476 	vnodefile = NULL;
477 	if ((p = strstr(mntops, "file=")) != NULL) {
478 		vnodefile = strdup(p + sizeof("file=") - 1);
479 		p = strchr(vnodefile, ',');
480 		if (p != NULL)
481 			*p = '\0';
482 	}
483 	if (vnodefile == NULL) {
484 		warnx("file option not found for %s", name);
485 		return (NULL);
486 	}
487 
488 	if (which_prog == SWAPON) {
489 		if (mdunit == -1) {
490 			error = run_cmd(&fd, "%s -l -n -f %s",
491 			    _PATH_MDCONFIG, vnodefile);
492 			if (error == 0) {
493 				/* md device found.  Ignore it. */
494 				close(fd);
495 				if (!qflag)
496 					warnx("%s: Device already in use",
497 					    vnodefile);
498 				free(vnodefile);
499 				return (NULL);
500 			}
501 			error = run_cmd(&fd, "%s -a -t vnode -n -f %s",
502 			    _PATH_MDCONFIG, vnodefile);
503 			if (error) {
504 				warnx("mdconfig (attach) error: file=%s",
505 				    vnodefile);
506 				free(vnodefile);
507 				return (NULL);
508 			}
509 			sfd = fdopen(fd, "r");
510 			if (sfd == NULL) {
511 				warn("mdconfig (attach) fdopen error");
512 				ret = NULL;
513 				goto err;
514 			}
515 			p = fgetln(sfd, &linelen);
516 			if (p == NULL &&
517 			    (linelen < 2 || linelen > sizeof(linebuf))) {
518 				warn("mdconfig (attach) unexpected output");
519 				ret = NULL;
520 				goto err;
521 			}
522 			strncpy(linebuf, p, linelen);
523 			linebuf[linelen - 1] = '\0';
524 			errno = 0;
525 			ul = strtoul(linebuf, &p, 10);
526 			if (errno == 0) {
527 				if (*p != '\0' || ul > INT_MAX)
528 					errno = EINVAL;
529 			}
530 			if (errno) {
531 				warn("mdconfig (attach) unexpected output: %s",
532 				    linebuf);
533 				ret = NULL;
534 				goto err;
535 			}
536 			mdunit = (int)ul;
537 		} else {
538 			error = run_cmd(&fd, "%s -l -n -f %s -u %d",
539 			    _PATH_MDCONFIG, vnodefile, mdunit);
540 			if (error == 0) {
541 				/* md device found.  Ignore it. */
542 				close(fd);
543 				if (qflag == 0)
544 					warnx("md%d on %s: Device already "
545 					    "in use", mdunit, vnodefile);
546 				free(vnodefile);
547 				return (NULL);
548 			}
549 			error = run_cmd(NULL, "%s -a -t vnode -u %d -f %s",
550 			    _PATH_MDCONFIG, mdunit, vnodefile);
551 			if (error) {
552 				warnx("mdconfig (attach) error: "
553 				    "md%d on file=%s", mdunit, vnodefile);
554 				free(vnodefile);
555 				return (NULL);
556 			}
557 		}
558 	} else /* SWAPOFF */ {
559 		if (mdunit == -1) {
560 			error = run_cmd(&fd, "%s -l -n -f %s",
561 			    _PATH_MDCONFIG, vnodefile);
562 			if (error) {
563 				/* md device not found.  Ignore it. */
564 				close(fd);
565 				if (!qflag)
566 					warnx("md on %s: Device not found",
567 					    vnodefile);
568 				free(vnodefile);
569 				return (NULL);
570 			}
571 			sfd = fdopen(fd, "r");
572 			if (sfd == NULL) {
573 				warn("mdconfig (list) fdopen error");
574 				ret = NULL;
575 				goto err;
576 			}
577 			p = fgetln(sfd, &linelen);
578 			if (p == NULL &&
579 			    (linelen < 2 || linelen > sizeof(linebuf) - 1)) {
580 				warn("mdconfig (list) unexpected output");
581 				ret = NULL;
582 				goto err;
583 			}
584 			strncpy(linebuf, p, linelen);
585 			linebuf[linelen - 1] = '\0';
586 			p = strchr(linebuf, ' ');
587 			if (p != NULL)
588 				*p = '\0';
589 			errno = 0;
590 			ul = strtoul(linebuf, &p, 10);
591 			if (errno == 0) {
592 				if (*p != '\0' || ul > INT_MAX)
593 					errno = EINVAL;
594 			}
595 			if (errno) {
596 				warn("mdconfig (list) unexpected output: %s",
597 				    linebuf);
598 				ret = NULL;
599 				goto err;
600 			}
601 			mdunit = (int)ul;
602 		} else {
603 			error = run_cmd(&fd, "%s -l -n -f %s -u %d",
604 			    _PATH_MDCONFIG, vnodefile, mdunit);
605 			if (error) {
606 				/* md device not found.  Ignore it. */
607 				close(fd);
608 				if (!qflag)
609 					warnx("md%d on %s: Device not found",
610 					    mdunit, vnodefile);
611 				free(vnodefile);
612 				return (NULL);
613 			}
614 		}
615 	}
616 	snprintf(mdpath, sizeof(mdpath), "%s%s%d", _PATH_DEV,
617 	    MD_NAME, mdunit);
618 	mdpath[sizeof(mdpath) - 1] = '\0';
619 	ret = swap_on_off_sfile(mdpath, doingall);
620 
621 	if (which_prog == SWAPOFF) {
622 		if (ret != NULL) {
623 			error = run_cmd(NULL, "%s -d -u %d",
624 			    _PATH_MDCONFIG, mdunit);
625 			if (error)
626 				warn("mdconfig (detach) detach failed: %s%s%d",
627 				    _PATH_DEV, MD_NAME, mdunit);
628 		}
629 	}
630 err:
631 	if (sfd != NULL)
632 		fclose(sfd);
633 	if (fd != -1)
634 		close(fd);
635 	free(vnodefile);
636 	return (ret);
637 }
638 
639 static int
640 run_cmd(int *ofd, const char *cmdline, ...)
641 {
642 	va_list ap;
643 	char **argv, **argvp, *cmd, *p;
644 	int argc, pid, status, rv;
645 	int pfd[2], nfd, dup2dn;
646 
647 	va_start(ap, cmdline);
648 	rv = vasprintf(&cmd, cmdline, ap);
649 	if (rv == -1) {
650 		warn("%s", __func__);
651 		va_end(ap);
652 		return (rv);
653 	}
654 	va_end(ap);
655 
656 	for (argc = 1, p = cmd; (p = strchr(p, ' ')) != NULL; p++)
657 		argc++;
658 	argv = (char **)malloc(sizeof(*argv) * (argc + 1));
659 	for (p = cmd, argvp = argv; (*argvp = strsep(&p, " ")) != NULL;)
660 		if (**argvp != '\0' && (++argvp > &argv[argc])) {
661 			*argvp = NULL;
662 			break;
663 		}
664 	/* The argv array ends up NULL-terminated here. */
665 #if 0
666 	{
667 		int i;
668 
669 		fprintf(stderr, "DEBUG: running:");
670 		/* Should be equivalent to 'cmd' (before strsep, of course). */
671 		for (i = 0; argv[i] != NULL; i++)
672 			fprintf(stderr, " %s", argv[i]);
673 		fprintf(stderr, "\n");
674 	}
675 #endif
676 	dup2dn = 1;
677 	if (ofd != NULL) {
678 		if (pipe(&pfd[0]) == -1) {
679 			warn("%s: pipe", __func__);
680 			return (-1);
681 		}
682 		*ofd = pfd[0];
683 		dup2dn = 0;
684 	}
685 	pid = fork();
686 	switch (pid) {
687 	case 0:
688 		/* Child process. */
689 		if (ofd != NULL)
690 			if (dup2(pfd[1], STDOUT_FILENO) < 0)
691 				err(1, "dup2 in %s", __func__);
692 		nfd = open(_PATH_DEVNULL, O_RDWR);
693 		if (nfd == -1)
694 			err(1, "%s: open %s", __func__, _PATH_DEVNULL);
695 		if (dup2(nfd, STDIN_FILENO) < 0)
696 			err(1, "%s: dup2", __func__);
697 		if (dup2dn && dup2(nfd, STDOUT_FILENO) < 0)
698 			err(1, "%s: dup2", __func__);
699 		if (dup2(nfd, STDERR_FILENO) < 0)
700 			err(1, "%s: dup2", __func__);
701 		execv(argv[0], argv);
702 		warn("exec: %s", argv[0]);
703 		_exit(-1);
704 	case -1:
705 		err(1, "%s: fork", __func__);
706 	}
707 	free(cmd);
708 	free(argv);
709 	while (waitpid(pid, &status, 0) != pid)
710 		;
711 	return (WEXITSTATUS(status));
712 }
713 
714 static const char *
715 swap_on_off_sfile(const char *name, int doingall)
716 {
717 	int error;
718 
719 	if (which_prog == SWAPON)
720 		error = swapon(name);
721 	else /* SWAPOFF */
722 		error = swapoff(name);
723 
724 	if (error == -1) {
725 		switch (errno) {
726 		case EBUSY:
727 			if (doingall == 0)
728 				warnx("%s: Device already in use", name);
729 			break;
730 		case EINVAL:
731 			if (which_prog == SWAPON)
732 				warnx("%s: NSWAPDEV limit reached", name);
733 			else if (doingall == 0)
734 				warn("%s", name);
735 			break;
736 		default:
737 			warn("%s", name);
738 			break;
739 		}
740 		return (NULL);
741 	}
742 	return (name);
743 }
744 
745 static void
746 usage(void)
747 {
748 
749 	fprintf(stderr, "usage: %s ", getprogname());
750 	switch(orig_prog) {
751 	case SWAPON:
752 	case SWAPOFF:
753 	    fprintf(stderr, "[-F fstab] -aLq | file ...\n");
754 	    break;
755 	case SWAPCTL:
756 	    fprintf(stderr, "[-AghklmsU] [-a file ... | -d file ...]\n");
757 	    break;
758 	}
759 	exit(1);
760 }
761 
762 static void
763 sizetobuf(char *buf, size_t bufsize, int hflag, long long val, int hlen,
764     long blocksize)
765 {
766 	char tmp[16];
767 
768 	if (hflag == 'H') {
769 		humanize_number(tmp, 5, (int64_t)val, "", HN_AUTOSCALE,
770 		    HN_B | HN_NOSPACE | HN_DECIMAL);
771 		snprintf(buf, bufsize, "%*s", hlen, tmp);
772 	} else
773 		snprintf(buf, bufsize, "%*lld", hlen, val / blocksize);
774 }
775 
776 static void
777 swaplist(int lflag, int sflag, int hflag)
778 {
779 	size_t mibsize, size;
780 	struct xswdev xsw;
781 	int hlen, mib[16], n, pagesize;
782 	long blocksize;
783 	long long total = 0;
784 	long long used = 0;
785 	long long tmp_total;
786 	long long tmp_used;
787 	char buf[32];
788 
789 	pagesize = getpagesize();
790 	switch(hflag) {
791 	case 'G':
792 		blocksize = 1024 * 1024 * 1024;
793 		strlcpy(buf, "1GB-blocks", sizeof(buf));
794 		hlen = 10;
795 		break;
796 	case 'H':
797 		blocksize = -1;
798 		strlcpy(buf, "Bytes", sizeof(buf));
799 		hlen = 10;
800 		break;
801 	case 'K':
802 		blocksize = 1024;
803 		strlcpy(buf, "1kB-blocks", sizeof(buf));
804 		hlen = 10;
805 		break;
806 	case 'M':
807 		blocksize = 1024 * 1024;
808 		strlcpy(buf, "1MB-blocks", sizeof(buf));
809 		hlen = 10;
810 		break;
811 	default:
812 		getbsize(&hlen, &blocksize);
813 		snprintf(buf, sizeof(buf), "%ld-blocks", blocksize);
814 		break;
815 	}
816 
817 	mibsize = nitems(mib);
818 	if (sysctlnametomib("vm.swap_info", mib, &mibsize) == -1)
819 		err(1, "sysctlnametomib()");
820 
821 	if (lflag) {
822 		printf("%-13s %*s %*s\n",
823 		    "Device:",
824 		    hlen, buf,
825 		    hlen, "Used:");
826 	}
827 
828 	for (n = 0; ; ++n) {
829 		mib[mibsize] = n;
830 		size = sizeof xsw;
831 		if (sysctl(mib, mibsize + 1, &xsw, &size, NULL, 0) == -1)
832 			break;
833 		if (xsw.xsw_version != XSWDEV_VERSION)
834 			errx(1, "xswdev version mismatch");
835 
836 		tmp_total = (long long)xsw.xsw_nblks * pagesize;
837 		tmp_used  = (long long)xsw.xsw_used * pagesize;
838 		total += tmp_total;
839 		used  += tmp_used;
840 		if (lflag) {
841 			sizetobuf(buf, sizeof(buf), hflag, tmp_total, hlen,
842 			    blocksize);
843 			printf("/dev/%-8s %s ", devname(xsw.xsw_dev, S_IFCHR),
844 			    buf);
845 			sizetobuf(buf, sizeof(buf), hflag, tmp_used, hlen,
846 			    blocksize);
847 			printf("%s\n", buf);
848 		}
849 	}
850 	if (errno != ENOENT)
851 		err(1, "sysctl()");
852 
853 	if (sflag) {
854 		sizetobuf(buf, sizeof(buf), hflag, total, hlen, blocksize);
855 		printf("Total:        %s ", buf);
856 		sizetobuf(buf, sizeof(buf), hflag, used, hlen, blocksize);
857 		printf("%s\n", buf);
858 	}
859 }
860 
861