swapctl.c revision 1.39 1 /* $NetBSD: swapctl.c,v 1.39 2013/01/01 19:01:10 dsl Exp $ */
2
3 /*
4 * Copyright (c) 1996, 1997, 1999 Matthew R. Green
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 /*
30 * swapctl command:
31 * -A add all devices listed as `sw' in /etc/fstab (also
32 * (sets the dump device, if listed in fstab)
33 * -D [<dev>|none] set dumpdev to <dev> or disable dumps
34 * -z show dumpdev
35 * -U remove all devices listed as `sw' in /etc/fstab.
36 * -t [blk|noblk|auto]
37 * if -A or -U , add (remove) either all block device
38 * or all non-block devices, or all swap partitions
39 * -q check if any swap or dump devices are defined in
40 * /etc/fstab
41 * -a <dev> add this device
42 * -d <dev> remove this swap device
43 * -f with -A -t auto, use the first swap as dump device
44 * -g use gigabytes
45 * -h use humanize_number(3) for listing
46 * -l list swap devices
47 * -m use megabytes
48 * -n print actions, but do not add/remove swap or
49 * with -A/-U
50 * -o with -A -t auto only configure the first swap as dump,
51 * (similar to -f), but do not add any further swap devs
52 * -s short listing of swap devices
53 * -k use kilobytes
54 * -p <pri> use this priority
55 * -c change priority
56 *
57 * or, if invoked as "swapon" (compatibility mode):
58 *
59 * -a all devices listed as `sw' in /etc/fstab
60 * -t same as -t above (feature not present in old
61 * swapon(8) command)
62 * <dev> add this device
63 */
64 #include <sys/cdefs.h>
65
66 #ifndef lint
67 __RCSID("$NetBSD: swapctl.c,v 1.39 2013/01/01 19:01:10 dsl Exp $");
68 #endif
69
70
71 #include <sys/param.h>
72 #include <sys/ioctl.h>
73 #include <sys/stat.h>
74 #include <sys/swap.h>
75 #include <sys/sysctl.h>
76 #include <sys/disk.h>
77 #include <sys/disklabel.h>
78
79 #include <unistd.h>
80 #include <err.h>
81 #include <errno.h>
82 #include <stdio.h>
83 #include <stdlib.h>
84 #include <string.h>
85 #include <fstab.h>
86 #include <fcntl.h>
87 #include <util.h>
88 #include <paths.h>
89
90 #include "swapctl.h"
91
92 static int command;
93
94 /*
95 * Commands for swapctl(8). These are mutually exclusive.
96 */
97 #define CMD_A 0x01 /* process /etc/fstab for adding */
98 #define CMD_D 0x02 /* set dumpdev */
99 #define CMD_U 0x04 /* process /etc/fstab for removing */
100 #define CMD_a 0x08 /* add a swap file/device */
101 #define CMD_c 0x10 /* change priority of a swap file/device */
102 #define CMD_d 0x20 /* delete a swap file/device */
103 #define CMD_l 0x40 /* list swap files/devices */
104 #define CMD_s 0x80 /* summary of swap files/devices */
105 #define CMD_z 0x100 /* show dump device */
106 #define CMD_q 0x200 /* check for dump/swap in /etc/fstab */
107
108 #define SET_COMMAND(cmd) \
109 do { \
110 if (command) \
111 usage(); \
112 command = (cmd); \
113 } while (0)
114
115 /*
116 * Commands that require a "path" argument at the end of the command
117 * line, and the ones which require that none exist.
118 */
119 #define REQUIRE_PATH (CMD_D | CMD_a | CMD_c | CMD_d)
120 #define REQUIRE_NOPATH (CMD_A | CMD_U | CMD_l | CMD_s | CMD_z | CMD_q)
121
122 /*
123 * Option flags, and the commands with which they are valid.
124 */
125 static int kflag; /* display in 1K^x blocks */
126 #define KFLAG_CMDS (CMD_l | CMD_s)
127 #define MFLAG_CMDS (CMD_l | CMD_s)
128 #define GFLAG_CMDS (CMD_l | CMD_s)
129
130 static int hflag; /* display with humanize_number */
131 #define HFLAG_CMDS (CMD_l | CMD_s)
132
133 static int pflag; /* priority was specified */
134 #define PFLAG_CMDS (CMD_A | CMD_a | CMD_c)
135
136 static char *tflag; /* swap device type (blk, noblk, auto) */
137 static int autoflag; /* 1, if tflag is "auto" */
138 #define TFLAG_CMDS (CMD_A | CMD_U)
139
140 static int fflag; /* first swap becomes dump */
141 #define FFLAG_CMDS (CMD_A)
142
143 static int oflag; /* only autoset dump device */
144 #define OFLAG_CMDS (CMD_A)
145
146 static int nflag; /* no execute, just print actions */
147 #define NFLAG_CMDS (CMD_A | CMD_U)
148
149 static int pri; /* uses 0 as default pri */
150
151 static void change_priority(char *);
152 static int add_swap(char *, int);
153 static int delete_swap(char *);
154 static void set_dumpdev1(char *);
155 static void set_dumpdev(char *);
156 static int get_dumpdev(void);
157 __dead static void do_fstab(int);
158 static int check_fstab(void);
159 static void do_localdevs(int);
160 static void do_localdisk(const char *, int);
161 static int do_wedgesofdisk(int fd, int);
162 static int do_partitionsofdisk(const char *, int fd, int);
163 __dead static void usage(void);
164 __dead static void swapon_command(int, char **);
165 #if 0
166 static void swapoff_command(int, char **);
167 #endif
168
169 int
170 main(int argc, char *argv[])
171 {
172 int c;
173
174 if (strcmp(getprogname(), "swapon") == 0) {
175 swapon_command(argc, argv);
176 /* NOTREACHED */
177 }
178
179 #if 0
180 if (strcmp(getprogname(), "swapoff") == 0) {
181 swapoff_command(argc, argv);
182 /* NOTREACHED */
183 }
184 #endif
185
186 while ((c = getopt(argc, argv, "ADUacdfghklmnop:qst:z")) != -1) {
187 switch (c) {
188 case 'A':
189 SET_COMMAND(CMD_A);
190 break;
191
192 case 'D':
193 SET_COMMAND(CMD_D);
194 break;
195
196 case 'U':
197 SET_COMMAND(CMD_U);
198 break;
199
200 case 'a':
201 SET_COMMAND(CMD_a);
202 break;
203
204 case 'c':
205 SET_COMMAND(CMD_c);
206 break;
207
208 case 'd':
209 SET_COMMAND(CMD_d);
210 break;
211
212 case 'f':
213 fflag = 1;
214 break;
215
216 case 'g':
217 kflag = 3; /* 1k ^ 3 */
218 break;
219
220 case 'h':
221 hflag = 1;
222 break;
223
224 case 'k':
225 kflag = 1;
226 break;
227
228 case 'l':
229 SET_COMMAND(CMD_l);
230 break;
231
232 case 'm':
233 kflag = 2; /* 1k ^ 2 */
234 break;
235
236 case 'n':
237 nflag = 1;
238 break;
239
240 case 'o':
241 oflag = 1;
242 break;
243
244 case 'p':
245 pflag = 1;
246 /* XXX strtol() */
247 pri = atoi(optarg);
248 break;
249
250 case 'q':
251 SET_COMMAND(CMD_q);
252 break;
253
254 case 's':
255 SET_COMMAND(CMD_s);
256 break;
257
258 case 't':
259 if (tflag != NULL)
260 usage();
261 tflag = optarg;
262 if (strcmp(tflag, "auto") == 0)
263 autoflag = 1;
264 break;
265
266 case 'z':
267 SET_COMMAND(CMD_z);
268 break;
269
270 default:
271 usage();
272 /* NOTREACHED */
273 }
274 }
275
276 /* Did the user specify a command? */
277 if (command == 0)
278 usage();
279
280 argv += optind;
281 argc -= optind;
282
283 switch (argc) {
284 case 0:
285 if (command & REQUIRE_PATH)
286 usage();
287 break;
288
289 case 1:
290 if (command & REQUIRE_NOPATH)
291 usage();
292 break;
293
294 default:
295 usage();
296 }
297
298 /* To change priority, you have to specify one. */
299 if ((command == CMD_c) && pflag == 0)
300 usage();
301
302 /* -f and -o are mutualy exclusive */
303 if (fflag && oflag)
304 usage();
305
306 /* Sanity-check -t */
307 if (tflag != NULL) {
308 if (command != CMD_A && command != CMD_U)
309 usage();
310 if (strcmp(tflag, "blk") != 0 &&
311 strcmp(tflag, "noblk") != 0 &&
312 strcmp(tflag, "auto") != 0)
313 usage();
314 }
315
316 /* Dispatch the command. */
317 switch (command) {
318 case CMD_l:
319 if (!list_swap(pri, kflag, pflag, 0, 1, hflag))
320 exit(1);
321 break;
322
323 case CMD_s:
324 list_swap(pri, kflag, pflag, 0, 0, hflag);
325 break;
326
327 case CMD_c:
328 change_priority(argv[0]);
329 break;
330
331 case CMD_a:
332 if (! add_swap(argv[0], pri))
333 exit(1);
334 break;
335
336 case CMD_d:
337 if (! delete_swap(argv[0]))
338 exit(1);
339 break;
340
341 case CMD_A:
342 if (autoflag)
343 do_localdevs(1);
344 else
345 do_fstab(1);
346 break;
347
348 case CMD_D:
349 set_dumpdev(argv[0]);
350 break;
351
352 case CMD_z:
353 if (!get_dumpdev())
354 exit(1);
355 break;
356
357 case CMD_U:
358 if (autoflag)
359 do_localdevs(0);
360 else
361 do_fstab(0);
362 break;
363 case CMD_q:
364 if (check_fstab()) {
365 printf("%s: there are swap or dump devices defined in "
366 _PATH_FSTAB "\n", getprogname());
367 exit(0);
368 } else {
369 printf("%s: no swap or dump devices in "
370 _PATH_FSTAB "\n", getprogname());
371 exit(1);
372 }
373 }
374
375 exit(0);
376 }
377
378 /*
379 * swapon_command: emulate the old swapon(8) program.
380 */
381 static void
382 swapon_command(int argc, char **argv)
383 {
384 int ch, fiztab = 0;
385
386 while ((ch = getopt(argc, argv, "at:")) != -1) {
387 switch (ch) {
388 case 'a':
389 fiztab = 1;
390 break;
391 case 't':
392 if (tflag != NULL)
393 usage();
394 tflag = optarg;
395 break;
396 default:
397 goto swapon_usage;
398 }
399 }
400 argc -= optind;
401 argv += optind;
402
403 if (fiztab) {
404 if (argc)
405 goto swapon_usage;
406 /* Sanity-check -t */
407 if (tflag != NULL) {
408 if (strcmp(tflag, "blk") != 0 &&
409 strcmp(tflag, "noblk") != 0)
410 usage();
411 }
412 do_fstab(1);
413 exit(0);
414 } else if (argc == 0 || tflag != NULL)
415 goto swapon_usage;
416
417 while (argc) {
418 if (! add_swap(argv[0], pri))
419 exit(1);
420 argc--;
421 argv++;
422 }
423 exit(0);
424 /* NOTREACHED */
425
426 swapon_usage:
427 fprintf(stderr, "usage: %s -a [-t blk|noblk]\n", getprogname());
428 fprintf(stderr, " %s <path> ...\n", getprogname());
429 exit(1);
430 }
431
432 /*
433 * change_priority: change the priority of a swap device.
434 */
435 static void
436 change_priority(char *path)
437 {
438
439 if (swapctl(SWAP_CTL, path, pri) < 0)
440 err(1, "%s", path);
441 }
442
443 /*
444 * add_swap: add the pathname to the list of swap devices.
445 */
446 static int
447 add_swap(char *path, int priority)
448 {
449 struct stat sb;
450 char buf[MAXPATHLEN];
451 char *spec;
452
453 if (getfsspecname(buf, sizeof(buf), path) == NULL)
454 goto oops;
455 spec = buf;
456
457 if (stat(spec, &sb) < 0)
458 goto oops;
459
460 if (sb.st_mode & S_IROTH)
461 warnx("WARNING: %s is readable by the world", path);
462 if (sb.st_mode & S_IWOTH)
463 warnx("WARNING: %s is writable by the world", path);
464
465 if (fflag || oflag) {
466 set_dumpdev1(spec);
467 if (oflag)
468 exit(0);
469 else
470 fflag = 0;
471 }
472
473 if (nflag)
474 return 1;
475
476 if (swapctl(SWAP_ON, spec, priority) < 0) {
477 oops:
478 err(1, "%s", path);
479 }
480 return (1);
481 }
482
483 /*
484 * delete_swap: remove the pathname to the list of swap devices.
485 */
486 static int
487 delete_swap(char *path)
488 {
489 char buf[MAXPATHLEN];
490 char *spec;
491
492 if (getfsspecname(buf, sizeof(buf), path) == NULL)
493 err(1, "%s", path);
494 spec = buf;
495
496 if (nflag)
497 return 1;
498
499 if (swapctl(SWAP_OFF, spec, pri) < 0)
500 err(1, "%s", path);
501 return (1);
502 }
503
504 static void
505 set_dumpdev1(char *spec)
506 {
507 int rv = 0;
508
509 if (!nflag) {
510 if (strcmp(spec, "none") == 0)
511 rv = swapctl(SWAP_DUMPOFF, NULL, 0);
512 else
513 rv = swapctl(SWAP_DUMPDEV, spec, 0);
514 }
515
516 if (rv == -1)
517 err(1, "could not set dump device to %s", spec);
518 else
519 printf("%s: setting dump device to %s\n", getprogname(), spec);
520 }
521
522 static void
523 set_dumpdev(char *path)
524 {
525 char buf[MAXPATHLEN];
526 char *spec;
527
528 if (getfsspecname(buf, sizeof(buf), path) == NULL)
529 err(1, "%s", path);
530 spec = buf;
531
532 return set_dumpdev1(spec);
533 }
534
535 static int
536 get_dumpdev(void)
537 {
538 dev_t dev;
539 char *name;
540
541 if (swapctl(SWAP_GETDUMPDEV, &dev, 0) == -1) {
542 warn("could not get dump device");
543 return 0;
544 } else if (dev == NODEV) {
545 printf("no dump device set\n");
546 return 0;
547 } else {
548 name = devname(dev, S_IFBLK);
549 printf("dump device is ");
550 if (name)
551 printf("%s\n", name);
552 else
553 printf("major %llu minor %llu\n",
554 (unsigned long long)major(dev),
555 (unsigned long long)minor(dev));
556 }
557 return 1;
558 }
559
560 static void
561 do_localdevs(int add)
562 {
563 size_t ressize;
564 char *disknames, *disk;
565 static const char mibname[] = "hw.disknames";
566
567 ressize = 0;
568 if (sysctlbyname(mibname, NULL, &ressize, NULL, 0))
569 return;
570 ressize += 200; /* add some arbitrary slope */
571 disknames = malloc(ressize);
572 if (sysctlbyname(mibname, disknames, &ressize, NULL, 0) == 0) {
573 for (disk = strtok(disknames, " "); disk;
574 disk = strtok(NULL, " "))
575 do_localdisk(disk, add);
576 }
577 free(disknames);
578 }
579
580 static void
581 do_localdisk(const char *disk, int add)
582 {
583 int fd;
584 char dvname[MAXPATHLEN];
585
586 if ((fd = opendisk(disk, O_RDONLY, dvname, sizeof(dvname), 0)) == -1)
587 return;
588
589 if (!do_wedgesofdisk(fd, add))
590 do_partitionsofdisk(disk, fd, add);
591
592 close(fd);
593 }
594
595 static int
596 do_wedgesofdisk(int fd, int add)
597 {
598 char devicename[MAXPATHLEN];
599 struct dkwedge_info *dkw;
600 struct dkwedge_list dkwl;
601 size_t bufsize;
602 u_int i;
603
604 dkw = NULL;
605 dkwl.dkwl_buf = dkw;
606 dkwl.dkwl_bufsize = 0;
607
608 for (;;) {
609 if (ioctl(fd, DIOCLWEDGES, &dkwl) == -1)
610 return 0;
611 if (dkwl.dkwl_nwedges == dkwl.dkwl_ncopied)
612 break;
613 bufsize = dkwl.dkwl_nwedges * sizeof(*dkw);
614 if (dkwl.dkwl_bufsize < bufsize) {
615 dkw = realloc(dkwl.dkwl_buf, bufsize);
616 if (dkw == NULL)
617 return 0;
618 dkwl.dkwl_buf = dkw;
619 dkwl.dkwl_bufsize = bufsize;
620 }
621 }
622
623 for (i = 0; i < dkwl.dkwl_ncopied; i++) {
624 if (strcmp(dkw[i].dkw_ptype, DKW_PTYPE_SWAP) != 0)
625 continue;
626 snprintf(devicename, sizeof(devicename), "%s%s", _PATH_DEV,
627 dkw[i].dkw_devname);
628 devicename[sizeof(devicename)-1] = '\0';
629
630 if (add) {
631 if (add_swap(devicename, pri)) {
632 printf(
633 "%s: adding %s as swap device at priority 0\n",
634 getprogname(), devicename);
635 }
636 } else {
637 if (delete_swap(devicename)) {
638 printf(
639 "%s: removing %s as swap device\n",
640 getprogname(), devicename);
641 }
642 }
643
644 }
645
646 free(dkw);
647 return dkwl.dkwl_nwedges != 0;
648 }
649
650 static int
651 do_partitionsofdisk(const char *prefix, int fd, int add)
652 {
653 char devicename[MAXPATHLEN];
654 struct disklabel lab;
655 uint i;
656
657 if (ioctl(fd, DIOCGDINFO, &lab) != 0)
658 return 0;
659
660 for (i = 0; i < lab.d_npartitions; i++) {
661 if (lab.d_partitions[i].p_fstype != FS_SWAP)
662 continue;
663 snprintf(devicename, sizeof(devicename), "%s%s%c", _PATH_DEV,
664 prefix, 'a'+i);
665 devicename[sizeof(devicename)-1] = '\0';
666
667 if (add) {
668 if (add_swap(devicename, pri)) {
669 printf(
670 "%s: adding %s as swap device at priority 0\n",
671 getprogname(), devicename);
672 }
673 } else {
674 if (delete_swap(devicename)) {
675 printf(
676 "%s: removing %s as swap device\n",
677 getprogname(), devicename);
678 }
679 }
680 }
681
682 return 1;
683 }
684
685 static int
686 check_fstab(void)
687 {
688 struct fstab *fp;
689
690 while ((fp = getfsent()) != NULL) {
691 if (strcmp(fp->fs_type, "dp") == 0)
692 return 1;
693
694 if (strcmp(fp->fs_type, "sw") == 0)
695 return 1;
696 }
697
698 return 0;
699 }
700
701 static void
702 do_fstab(int add)
703 {
704 struct fstab *fp;
705 char *s;
706 long priority;
707 struct stat st;
708 int isblk;
709 int success = 0; /* set to 1 after a successful operation */
710 int error = 0; /* set to 1 after an error */
711
712 #ifdef RESCUEDIR
713 #define PATH_MOUNT RESCUEDIR "/mount_nfs"
714 #define PATH_UMOUNT RESCUEDIR "/umount"
715 #else
716 #define PATH_MOUNT "/sbin/mount_nfs"
717 #define PATH_UMOUNT "/sbin/umount"
718 #endif
719
720 char cmd[2*PATH_MAX+sizeof(PATH_MOUNT)+2];
721
722 #define PRIORITYEQ "priority="
723 #define NFSMNTPT "nfsmntpt="
724 while ((fp = getfsent()) != NULL) {
725 char buf[MAXPATHLEN];
726 char *spec, *fsspec;
727
728 if (getfsspecname(buf, sizeof(buf), fp->fs_spec) == NULL) {
729 warn("%s", buf);
730 continue;
731 }
732 fsspec = spec = buf;
733 cmd[0] = '\0';
734
735 if (strcmp(fp->fs_type, "dp") == 0 && add) {
736 set_dumpdev1(spec);
737 continue;
738 }
739
740 if (strcmp(fp->fs_type, "sw") != 0)
741 continue;
742
743 /* handle dp as mnt option */
744 if (strstr(fp->fs_mntops, "dp") && add)
745 set_dumpdev1(spec);
746
747 isblk = 0;
748
749 if ((s = strstr(fp->fs_mntops, PRIORITYEQ)) != NULL) {
750 s += sizeof(PRIORITYEQ) - 1;
751 priority = atol(s);
752 } else
753 priority = pri;
754
755 if ((s = strstr(fp->fs_mntops, NFSMNTPT)) != NULL) {
756 char *t;
757
758 /*
759 * Skip this song and dance if we're only
760 * doing block devices.
761 */
762 if (tflag != NULL && strcmp(tflag, "blk") == 0)
763 continue;
764
765 t = strpbrk(s, ",");
766 if (t != 0)
767 *t = '\0';
768 spec = strdup(s + strlen(NFSMNTPT));
769 if (t != 0)
770 *t = ',';
771
772 if (spec == NULL)
773 errx(1, "Out of memory");
774
775 if (strlen(spec) == 0) {
776 warnx("empty mountpoint");
777 free(spec);
778 continue;
779 }
780 if (add) {
781 snprintf(cmd, sizeof(cmd), "%s %s %s",
782 PATH_MOUNT, fsspec, spec);
783 if (system(cmd) != 0) {
784 warnx("%s: mount failed", fsspec);
785 continue;
786 }
787 } else {
788 snprintf(cmd, sizeof(cmd), "%s %s",
789 PATH_UMOUNT, fsspec);
790 }
791 } else {
792 /*
793 * Determine blk-ness.
794 */
795 if (stat(spec, &st) < 0) {
796 warn("%s", spec);
797 continue;
798 }
799 if (S_ISBLK(st.st_mode))
800 isblk = 1;
801 }
802
803 /*
804 * Skip this type if we're told to.
805 */
806 if (tflag != NULL) {
807 if (strcmp(tflag, "blk") == 0 && isblk == 0)
808 continue;
809 if (strcmp(tflag, "noblk") == 0 && isblk == 1)
810 continue;
811 }
812
813 if (add) {
814 if (add_swap(spec, (int)priority)) {
815 success = 1;
816 printf(
817 "%s: adding %s as swap device at priority %d\n",
818 getprogname(), fsspec, (int)priority);
819 } else {
820 error = 1;
821 fprintf(stderr,
822 "%s: failed to add %s as swap device\n",
823 getprogname(), fsspec);
824 }
825 } else {
826 if (delete_swap(spec)) {
827 success = 1;
828 printf(
829 "%s: removing %s as swap device\n",
830 getprogname(), fsspec);
831 } else {
832 error = 1;
833 fprintf(stderr,
834 "%s: failed to remove %s as swap device\n",
835 getprogname(), fsspec);
836 }
837 if (cmd[0]) {
838 if (system(cmd) != 0) {
839 warnx("%s: umount failed", fsspec);
840 error = 1;
841 continue;
842 }
843 }
844 }
845
846 if (spec != fsspec)
847 free(spec);
848 }
849 if (error)
850 exit(1);
851 else if (success)
852 exit(0);
853 else
854 exit(2); /* not really an error, but no swap devices found */
855 }
856
857 static void
858 usage(void)
859 {
860 const char *progname = getprogname();
861
862 fprintf(stderr, "usage: %s -A [-f|-o] [-n] [-p priority] "
863 "[-t blk|noblk|auto]\n", progname);
864 fprintf(stderr, " %s -a [-p priority] path\n", progname);
865 fprintf(stderr, " %s -q\n", progname);
866 fprintf(stderr, " %s -c -p priority path\n", progname);
867 fprintf(stderr, " %s -D dumpdev|none\n", progname);
868 fprintf(stderr, " %s -d path\n", progname);
869 fprintf(stderr, " %s -l | -s [-k|-m|-g|-h]\n", progname);
870 fprintf(stderr, " %s -U [-n] [-t blk|noblk|auto]\n", progname);
871 fprintf(stderr, " %s -z\n", progname);
872 exit(1);
873 }
874