xref: /freebsd/sbin/swapon/swapon.c (revision 0b3105a37d7adcadcb720112fed4dc4e8040be99)
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[PATH_MAX];
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 	basename_r(name, base);
231 
232 	/* Swap on encrypted device by GEOM_BDE. */
233 	if (fnmatch("*.bde", base, 0) == 0)
234 		return (swap_on_off_gbde(name, doingall));
235 
236 	/* Swap on encrypted device by GEOM_ELI. */
237 	if (fnmatch("*.eli", base, 0) == 0)
238 		return (swap_on_off_geli(name, mntops, doingall));
239 
240 	/* Swap on special file. */
241 	return (swap_on_off_sfile(name, doingall));
242 }
243 
244 /* Strip off .bde or .eli suffix from swap device name */
245 static char *
246 swap_basename(const char *name)
247 {
248 	char *dname, *p;
249 
250 	dname = strdup(name);
251 	p = strrchr(dname, '.');
252 	/* assert(p != NULL); */
253 	*p = '\0';
254 
255 	return (dname);
256 }
257 
258 static const char *
259 swap_on_off_gbde(const char *name, int doingall)
260 {
261 	const char *ret;
262 	char pass[64 * 2 + 1];
263 	unsigned char bpass[64];
264 	char *dname;
265 	int i, error;
266 
267 	dname = swap_basename(name);
268 	if (dname == NULL)
269 		return (NULL);
270 
271 	if (which_prog == SWAPON) {
272 		arc4random_buf(bpass, sizeof(bpass));
273 		for (i = 0; i < (int)sizeof(bpass); i++)
274 			sprintf(&pass[2 * i], "%02x", bpass[i]);
275 		pass[sizeof(pass) - 1] = '\0';
276 
277 		error = run_cmd(NULL, "%s init %s -P %s", _PATH_GBDE,
278 		    dname, pass);
279 		if (error) {
280 			/* bde device found.  Ignore it. */
281 			free(dname);
282 			if (qflag == 0)
283 				warnx("%s: Device already in use", name);
284 			return (NULL);
285 		}
286 		error = run_cmd(NULL, "%s attach %s -p %s", _PATH_GBDE,
287 		    dname, pass);
288 		free(dname);
289 		if (error) {
290 			warnx("gbde (attach) error: %s", name);
291 			return (NULL);
292 		}
293 	}
294 
295 	ret = swap_on_off_sfile(name, doingall);
296 
297 	if (which_prog == SWAPOFF) {
298 		error = run_cmd(NULL, "%s detach %s", _PATH_GBDE, dname);
299 		free(dname);
300 		if (error) {
301 			/* bde device not found.  Ignore it. */
302 			if (qflag == 0)
303 				warnx("%s: Device not found", name);
304 			return (NULL);
305 		}
306 	}
307 
308 	return (ret);
309 }
310 
311 /* Build geli(8) arguments from mntops */
312 static char *
313 swap_on_geli_args(const char *mntops)
314 {
315 	const char *aalgo, *ealgo, *keylen_str, *sectorsize_str;
316 	const char *aflag, *eflag, *lflag, *Tflag, *sflag;
317 	char *p, *args, *token, *string, *ops;
318 	int pagesize;
319 	size_t pagesize_len;
320 	u_long ul;
321 
322 	/* Use built-in defaults for geli(8). */
323 	aalgo = ealgo = keylen_str = "";
324 	aflag = eflag = lflag = Tflag = "";
325 
326 	/* We will always specify sectorsize. */
327 	sflag = " -s ";
328 	sectorsize_str = NULL;
329 
330 	if (mntops != NULL) {
331 		string = ops = strdup(mntops);
332 
333 		while ((token = strsep(&string, ",")) != NULL) {
334 			if ((p = strstr(token, "aalgo=")) == token) {
335 				aalgo = p + sizeof("aalgo=") - 1;
336 				aflag = " -a ";
337 			} else if ((p = strstr(token, "ealgo=")) == token) {
338 				ealgo = p + sizeof("ealgo=") - 1;
339 				eflag = " -e ";
340 			} else if ((p = strstr(token, "keylen=")) == token) {
341 				keylen_str = p + sizeof("keylen=") - 1;
342 				errno = 0;
343 				ul = strtoul(keylen_str, &p, 10);
344 				if (errno == 0) {
345 					if (*p != '\0' || ul > INT_MAX)
346 						errno = EINVAL;
347 				}
348 				if (errno) {
349 					warn("Invalid keylen: %s", keylen_str);
350 					free(ops);
351 					return (NULL);
352 				}
353 				lflag = " -l ";
354 			} else if ((p = strstr(token, "sectorsize=")) == token) {
355 				sectorsize_str = p + sizeof("sectorsize=") - 1;
356 				errno = 0;
357 				ul = strtoul(sectorsize_str, &p, 10);
358 				if (errno == 0) {
359 					if (*p != '\0' || ul > INT_MAX)
360 						errno = EINVAL;
361 				}
362 				if (errno) {
363 					warn("Invalid sectorsize: %s",
364 					    sectorsize_str);
365 					free(ops);
366 					return (NULL);
367 				}
368 			} else if ((p = strstr(token, "notrim")) == token) {
369 				Tflag = " -T ";
370 			} else if (strcmp(token, "sw") != 0) {
371 				warnx("Invalid option: %s", token);
372 				free(ops);
373 				return (NULL);
374 			}
375 		}
376 	} else
377 		ops = NULL;
378 
379 	/*
380 	 * If we do not have a sector size at this point, fill in
381 	 * pagesize as sector size.
382 	 */
383 	if (sectorsize_str == NULL) {
384 		/* Use pagesize as default sectorsize. */
385 		pagesize = getpagesize();
386 		pagesize_len = snprintf(NULL, 0, "%d", pagesize) + 1;
387 		p = alloca(pagesize_len);
388 		snprintf(p, pagesize_len, "%d", pagesize);
389 		sectorsize_str = p;
390 	}
391 
392 	(void)asprintf(&args, "%s%s%s%s%s%s%s%s%s -d",
393 	    aflag, aalgo, eflag, ealgo, lflag, keylen_str, Tflag,
394 	    sflag, sectorsize_str);
395 
396 	free(ops);
397 	return (args);
398 }
399 
400 static const char *
401 swap_on_off_geli(const char *name, char *mntops, int doingall)
402 {
403 	struct stat sb;
404 	char *dname, *args;
405 	int error;
406 
407 	error = stat(name, &sb);
408 
409 	if (which_prog == SWAPON) do {
410 		/* Skip if the .eli device already exists. */
411 		if (error == 0)
412 			break;
413 
414 		args = swap_on_geli_args(mntops);
415 		if (args == NULL)
416 			return (NULL);
417 
418 		dname = swap_basename(name);
419 		if (dname == NULL) {
420 			free(args);
421 			return (NULL);
422 		}
423 
424 		error = run_cmd(NULL, "%s onetime%s %s", _PATH_GELI, args,
425 		    dname);
426 
427 		free(dname);
428 		free(args);
429 
430 		if (error) {
431 			/* error occured during creation. */
432 			if (qflag == 0)
433 				warnx("%s: Invalid parameters", name);
434 			return (NULL);
435 		}
436 	} while (0);
437 
438 	return (swap_on_off_sfile(name, doingall));
439 }
440 
441 static const char *
442 swap_on_off_md(const char *name, char *mntops, int doingall)
443 {
444 	FILE *sfd;
445 	int fd, mdunit, error;
446 	const char *ret;
447 	static char mdpath[PATH_MAX], linebuf[PATH_MAX];
448 	char *p, *vnodefile;
449 	size_t linelen;
450 	u_long ul;
451 
452 	fd = -1;
453 	sfd = NULL;
454 	if (strlen(name) == (sizeof(MD_NAME) - 1))
455 		mdunit = -1;
456 	else {
457 		errno = 0;
458 		ul = strtoul(name + 2, &p, 10);
459 		if (errno == 0) {
460 			if (*p != '\0' || ul > INT_MAX)
461 				errno = EINVAL;
462 		}
463 		if (errno) {
464 			warn("Bad device unit: %s", name);
465 			return (NULL);
466 		}
467 		mdunit = (int)ul;
468 	}
469 
470 	vnodefile = NULL;
471 	if ((p = strstr(mntops, "file=")) != NULL) {
472 		vnodefile = strdup(p + sizeof("file=") - 1);
473 		p = strchr(vnodefile, ',');
474 		if (p != NULL)
475 			*p = '\0';
476 	}
477 	if (vnodefile == NULL) {
478 		warnx("file option not found for %s", name);
479 		return (NULL);
480 	}
481 
482 	if (which_prog == SWAPON) {
483 		if (mdunit == -1) {
484 			error = run_cmd(&fd, "%s -l -n -f %s",
485 			    _PATH_MDCONFIG, vnodefile);
486 			if (error == 0) {
487 				/* md device found.  Ignore it. */
488 				close(fd);
489 				if (!qflag)
490 					warnx("%s: Device already in use",
491 					    vnodefile);
492 				free(vnodefile);
493 				return (NULL);
494 			}
495 			error = run_cmd(&fd, "%s -a -t vnode -n -f %s",
496 			    _PATH_MDCONFIG, vnodefile);
497 			if (error) {
498 				warnx("mdconfig (attach) error: file=%s",
499 				    vnodefile);
500 				free(vnodefile);
501 				return (NULL);
502 			}
503 			sfd = fdopen(fd, "r");
504 			if (sfd == NULL) {
505 				warn("mdconfig (attach) fdopen error");
506 				ret = NULL;
507 				goto err;
508 			}
509 			p = fgetln(sfd, &linelen);
510 			if (p == NULL &&
511 			    (linelen < 2 || linelen > sizeof(linebuf))) {
512 				warn("mdconfig (attach) unexpected output");
513 				ret = NULL;
514 				goto err;
515 			}
516 			strncpy(linebuf, p, linelen);
517 			linebuf[linelen - 1] = '\0';
518 			errno = 0;
519 			ul = strtoul(linebuf, &p, 10);
520 			if (errno == 0) {
521 				if (*p != '\0' || ul > INT_MAX)
522 					errno = EINVAL;
523 			}
524 			if (errno) {
525 				warn("mdconfig (attach) unexpected output: %s",
526 				    linebuf);
527 				ret = NULL;
528 				goto err;
529 			}
530 			mdunit = (int)ul;
531 		} else {
532 			error = run_cmd(&fd, "%s -l -n -f %s -u %d",
533 			    _PATH_MDCONFIG, vnodefile, mdunit);
534 			if (error == 0) {
535 				/* md device found.  Ignore it. */
536 				close(fd);
537 				if (qflag == 0)
538 					warnx("md%d on %s: Device already "
539 					    "in use", mdunit, vnodefile);
540 				free(vnodefile);
541 				return (NULL);
542 			}
543 			error = run_cmd(NULL, "%s -a -t vnode -u %d -f %s",
544 			    _PATH_MDCONFIG, mdunit, vnodefile);
545 			if (error) {
546 				warnx("mdconfig (attach) error: "
547 				    "md%d on file=%s", mdunit, vnodefile);
548 				free(vnodefile);
549 				return (NULL);
550 			}
551 		}
552 	} else /* SWAPOFF */ {
553 		if (mdunit == -1) {
554 			error = run_cmd(&fd, "%s -l -n -f %s",
555 			    _PATH_MDCONFIG, vnodefile);
556 			if (error) {
557 				/* md device not found.  Ignore it. */
558 				close(fd);
559 				if (!qflag)
560 					warnx("md on %s: Device not found",
561 					    vnodefile);
562 				free(vnodefile);
563 				return (NULL);
564 			}
565 			sfd = fdopen(fd, "r");
566 			if (sfd == NULL) {
567 				warn("mdconfig (list) fdopen error");
568 				ret = NULL;
569 				goto err;
570 			}
571 			p = fgetln(sfd, &linelen);
572 			if (p == NULL &&
573 			    (linelen < 2 || linelen > sizeof(linebuf) - 1)) {
574 				warn("mdconfig (list) unexpected output");
575 				ret = NULL;
576 				goto err;
577 			}
578 			strncpy(linebuf, p, linelen);
579 			linebuf[linelen - 1] = '\0';
580 			p = strchr(linebuf, ' ');
581 			if (p != NULL)
582 				*p = '\0';
583 			errno = 0;
584 			ul = strtoul(linebuf, &p, 10);
585 			if (errno == 0) {
586 				if (*p != '\0' || ul > INT_MAX)
587 					errno = EINVAL;
588 			}
589 			if (errno) {
590 				warn("mdconfig (list) unexpected output: %s",
591 				    linebuf);
592 				ret = NULL;
593 				goto err;
594 			}
595 			mdunit = (int)ul;
596 		} else {
597 			error = run_cmd(&fd, "%s -l -n -f %s -u %d",
598 			    _PATH_MDCONFIG, vnodefile, mdunit);
599 			if (error) {
600 				/* md device not found.  Ignore it. */
601 				close(fd);
602 				if (!qflag)
603 					warnx("md%d on %s: Device not found",
604 					    mdunit, vnodefile);
605 				free(vnodefile);
606 				return (NULL);
607 			}
608 		}
609 	}
610 	snprintf(mdpath, sizeof(mdpath), "%s%s%d", _PATH_DEV,
611 	    MD_NAME, mdunit);
612 	mdpath[sizeof(mdpath) - 1] = '\0';
613 	ret = swap_on_off_sfile(mdpath, doingall);
614 
615 	if (which_prog == SWAPOFF) {
616 		if (ret != NULL) {
617 			error = run_cmd(NULL, "%s -d -u %d",
618 			    _PATH_MDCONFIG, mdunit);
619 			if (error)
620 				warn("mdconfig (detach) detach failed: %s%s%d",
621 				    _PATH_DEV, MD_NAME, mdunit);
622 		}
623 	}
624 err:
625 	if (sfd != NULL)
626 		fclose(sfd);
627 	if (fd != -1)
628 		close(fd);
629 	free(vnodefile);
630 	return (ret);
631 }
632 
633 static int
634 run_cmd(int *ofd, const char *cmdline, ...)
635 {
636 	va_list ap;
637 	char **argv, **argvp, *cmd, *p;
638 	int argc, pid, status, rv;
639 	int pfd[2], nfd, dup2dn;
640 
641 	va_start(ap, cmdline);
642 	rv = vasprintf(&cmd, cmdline, ap);
643 	if (rv == -1) {
644 		warn("%s", __func__);
645 		va_end(ap);
646 		return (rv);
647 	}
648 	va_end(ap);
649 
650 	for (argc = 1, p = cmd; (p = strchr(p, ' ')) != NULL; p++)
651 		argc++;
652 	argv = (char **)malloc(sizeof(*argv) * (argc + 1));
653 	for (p = cmd, argvp = argv; (*argvp = strsep(&p, " ")) != NULL;)
654 		if (**argvp != '\0' && (++argvp > &argv[argc])) {
655 			*argvp = NULL;
656 			break;
657 		}
658 	/* The argv array ends up NULL-terminated here. */
659 #if 0
660 	{
661 		int i;
662 
663 		fprintf(stderr, "DEBUG: running:");
664 		/* Should be equivalent to 'cmd' (before strsep, of course). */
665 		for (i = 0; argv[i] != NULL; i++)
666 			fprintf(stderr, " %s", argv[i]);
667 		fprintf(stderr, "\n");
668 	}
669 #endif
670 	dup2dn = 1;
671 	if (ofd != NULL) {
672 		if (pipe(&pfd[0]) == -1) {
673 			warn("%s: pipe", __func__);
674 			return (-1);
675 		}
676 		*ofd = pfd[0];
677 		dup2dn = 0;
678 	}
679 	pid = fork();
680 	switch (pid) {
681 	case 0:
682 		/* Child process. */
683 		if (ofd != NULL)
684 			if (dup2(pfd[1], STDOUT_FILENO) < 0)
685 				err(1, "dup2 in %s", __func__);
686 		nfd = open(_PATH_DEVNULL, O_RDWR);
687 		if (nfd == -1)
688 			err(1, "%s: open %s", __func__, _PATH_DEVNULL);
689 		if (dup2(nfd, STDIN_FILENO) < 0)
690 			err(1, "%s: dup2", __func__);
691 		if (dup2dn && dup2(nfd, STDOUT_FILENO) < 0)
692 			err(1, "%s: dup2", __func__);
693 		if (dup2(nfd, STDERR_FILENO) < 0)
694 			err(1, "%s: dup2", __func__);
695 		execv(argv[0], argv);
696 		warn("exec: %s", argv[0]);
697 		_exit(-1);
698 	case -1:
699 		err(1, "%s: fork", __func__);
700 	}
701 	free(cmd);
702 	free(argv);
703 	while (waitpid(pid, &status, 0) != pid)
704 		;
705 	return (WEXITSTATUS(status));
706 }
707 
708 static const char *
709 swap_on_off_sfile(const char *name, int doingall)
710 {
711 	int error;
712 
713 	if (which_prog == SWAPON)
714 		error = swapon(name);
715 	else /* SWAPOFF */
716 		error = swapoff(name);
717 
718 	if (error == -1) {
719 		switch (errno) {
720 		case EBUSY:
721 			if (doingall == 0)
722 				warnx("%s: Device already in use", name);
723 			break;
724 		case EINVAL:
725 			if (which_prog == SWAPON)
726 				warnx("%s: NSWAPDEV limit reached", name);
727 			else if (doingall == 0)
728 				warn("%s", name);
729 			break;
730 		default:
731 			warn("%s", name);
732 			break;
733 		}
734 		return (NULL);
735 	}
736 	return (name);
737 }
738 
739 static void
740 usage(void)
741 {
742 
743 	fprintf(stderr, "usage: %s ", getprogname());
744 	switch(orig_prog) {
745 	case SWAPON:
746 	case SWAPOFF:
747 	    fprintf(stderr, "[-F fstab] -aLq | file ...\n");
748 	    break;
749 	case SWAPCTL:
750 	    fprintf(stderr, "[-AghklmsU] [-a file ... | -d file ...]\n");
751 	    break;
752 	}
753 	exit(1);
754 }
755 
756 static void
757 sizetobuf(char *buf, size_t bufsize, int hflag, long long val, int hlen,
758     long blocksize)
759 {
760 	char tmp[16];
761 
762 	if (hflag == 'H') {
763 		humanize_number(tmp, 5, (int64_t)val, "", HN_AUTOSCALE,
764 		    HN_B | HN_NOSPACE | HN_DECIMAL);
765 		snprintf(buf, bufsize, "%*s", hlen, tmp);
766 	} else
767 		snprintf(buf, bufsize, "%*lld", hlen, val / blocksize);
768 }
769 
770 static void
771 swaplist(int lflag, int sflag, int hflag)
772 {
773 	size_t mibsize, size;
774 	struct xswdev xsw;
775 	int hlen, mib[16], n, pagesize;
776 	long blocksize;
777 	long long total = 0;
778 	long long used = 0;
779 	long long tmp_total;
780 	long long tmp_used;
781 	char buf[32];
782 
783 	pagesize = getpagesize();
784 	switch(hflag) {
785 	case 'G':
786 		blocksize = 1024 * 1024 * 1024;
787 		strlcpy(buf, "1GB-blocks", sizeof(buf));
788 		hlen = 10;
789 		break;
790 	case 'H':
791 		blocksize = -1;
792 		strlcpy(buf, "Bytes", sizeof(buf));
793 		hlen = 10;
794 		break;
795 	case 'K':
796 		blocksize = 1024;
797 		strlcpy(buf, "1kB-blocks", sizeof(buf));
798 		hlen = 10;
799 		break;
800 	case 'M':
801 		blocksize = 1024 * 1024;
802 		strlcpy(buf, "1MB-blocks", sizeof(buf));
803 		hlen = 10;
804 		break;
805 	default:
806 		getbsize(&hlen, &blocksize);
807 		snprintf(buf, sizeof(buf), "%ld-blocks", blocksize);
808 		break;
809 	}
810 
811 	mibsize = nitems(mib);
812 	if (sysctlnametomib("vm.swap_info", mib, &mibsize) == -1)
813 		err(1, "sysctlnametomib()");
814 
815 	if (lflag) {
816 		printf("%-13s %*s %*s\n",
817 		    "Device:",
818 		    hlen, buf,
819 		    hlen, "Used:");
820 	}
821 
822 	for (n = 0; ; ++n) {
823 		mib[mibsize] = n;
824 		size = sizeof xsw;
825 		if (sysctl(mib, mibsize + 1, &xsw, &size, NULL, 0) == -1)
826 			break;
827 		if (xsw.xsw_version != XSWDEV_VERSION)
828 			errx(1, "xswdev version mismatch");
829 
830 		tmp_total = (long long)xsw.xsw_nblks * pagesize;
831 		tmp_used  = (long long)xsw.xsw_used * pagesize;
832 		total += tmp_total;
833 		used  += tmp_used;
834 		if (lflag) {
835 			sizetobuf(buf, sizeof(buf), hflag, tmp_total, hlen,
836 			    blocksize);
837 			printf("/dev/%-8s %s ", devname(xsw.xsw_dev, S_IFCHR),
838 			    buf);
839 			sizetobuf(buf, sizeof(buf), hflag, tmp_used, hlen,
840 			    blocksize);
841 			printf("%s\n", buf);
842 		}
843 	}
844 	if (errno != ENOENT)
845 		err(1, "sysctl()");
846 
847 	if (sflag) {
848 		sizetobuf(buf, sizeof(buf), hflag, total, hlen, blocksize);
849 		printf("Total:        %s ", buf);
850 		sizetobuf(buf, sizeof(buf), hflag, used, hlen, blocksize);
851 		printf("%s\n", buf);
852 	}
853 }
854 
855