xref: /netbsd-src/sbin/swapctl/swapctl.c (revision 3b435a73967be44dfb4a27315acd72bfacde430c) 
1 /*	$NetBSD: swapctl.c,v 1.11 1999/04/26 01:02:25 mrg 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  * 3. The name of the author may not be used to endorse or promote products
16  *    derived from this software without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
23  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
24  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
25  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
26  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 /*
32  * swapctl command:
33  *	-A		add all devices listed as `sw' in /etc/fstab (also
34  *			(sets the the dump device, if listed in fstab)
35  *	-D <dev>	set dumpdev to <dev>
36  *	-t [blk|noblk]	if -A, add either all block device or all non-block
37  *			devices
38  *	-a <dev>	add this device
39  *	-d <dev>	remove this swap device (not supported yet)
40  *	-l		list swap devices
41  *	-s		short listing of swap devices
42  *	-k		use kilobytes
43  *	-p <pri>	use this priority
44  *	-c		change priority
45  *
46  * or, if invoked as "swapon" (compatibility mode):
47  *
48  *	-a		all devices listed as `sw' in /etc/fstab
49  *	-t		same as -t above (feature not present in old
50  *			swapon(8) command)
51  *	<dev>		add this device
52  */
53 
54 #include <sys/param.h>
55 #include <sys/stat.h>
56 
57 #include <vm/vm_swap.h>
58 
59 #include <unistd.h>
60 #include <err.h>
61 #include <errno.h>
62 #include <stdio.h>
63 #include <stdlib.h>
64 #include <string.h>
65 #include <fstab.h>
66 
67 #include "swapctl.h"
68 
69 int	command;
70 
71 /*
72  * Commands for swapctl(8).  These are mutually exclusive.
73  */
74 #define	CMD_A		0x01	/* process /etc/fstab */
75 #define	CMD_D		0x02	/* set dumpdev */
76 #define	CMD_a		0x04	/* add a swap file/device */
77 #define	CMD_c		0x08	/* change priority of a swap file/device */
78 #define	CMD_d		0x10	/* delete a swap file/device */
79 #define	CMD_l		0x20	/* list swap files/devices */
80 #define	CMD_s		0x40	/* summary of swap files/devices */
81 
82 #define	SET_COMMAND(cmd) \
83 do { \
84 	if (command) \
85 		usage(); \
86 	command = (cmd); \
87 } while (0)
88 
89 /*
90  * Commands that require a "path" argument at the end of the command
91  * line, and the ones which require that none exist.
92  */
93 #define	REQUIRE_PATH	(CMD_D | CMD_a | CMD_c | CMD_d)
94 #define	REQUIRE_NOPATH	(CMD_A | CMD_l | CMD_s)
95 
96 /*
97  * Option flags, and the commands with which they are valid.
98  */
99 int	kflag;		/* display in 1K blocks */
100 #define	KFLAG_CMDS	(CMD_l | CMD_s)
101 
102 int	pflag;		/* priority was specified */
103 #define	PFLAG_CMDS	(CMD_A | CMD_a | CMD_c)
104 
105 char	*tflag;		/* swap device type (blk or noblk) */
106 #define	TFLAG_CMDS	(CMD_A)
107 
108 int	pri;		/* uses 0 as default pri */
109 
110 static	void change_priority __P((const char *));
111 static	void add_swap __P((const char *));
112 static	void delete_swap __P((const char *));
113 static	void set_dumpdev __P((const char *));
114 	int  main __P((int, char *[]));
115 static	void do_fstab __P((void));
116 static	void usage __P((void));
117 static	void swapon_command __P((int, char **));
118 #if 0
119 static	void swapoff_command __P((int, char **));
120 #endif
121 
122 extern	char *__progname;	/* from crt0.o */
123 
124 int
125 main(argc, argv)
126 	int	argc;
127 	char	*argv[];
128 {
129 	int	c;
130 
131 	if (strcmp(__progname, "swapon") == 0) {
132 		swapon_command(argc, argv);
133 		/* NOTREACHED */
134 	}
135 
136 #if 0
137 	if (strcmp(__progname, "swapoff") == 0) {
138 		swapoff_command(argc, argv);
139 		/* NOTREACHED */
140 	}
141 #endif
142 
143 	while ((c = getopt(argc, argv, "ADacdlkp:st:")) != -1) {
144 		switch (c) {
145 		case 'A':
146 			SET_COMMAND(CMD_A);
147 			break;
148 
149 		case 'D':
150 			SET_COMMAND(CMD_D);
151 			break;
152 
153 		case 'a':
154 			SET_COMMAND(CMD_a);
155 			break;
156 
157 		case 'c':
158 			SET_COMMAND(CMD_c);
159 			break;
160 
161 		case 'd':
162 			SET_COMMAND(CMD_d);
163 			break;
164 
165 		case 'l':
166 			SET_COMMAND(CMD_l);
167 			break;
168 
169 		case 'k':
170 			kflag = 1;
171 			break;
172 
173 		case 'p':
174 			pflag = 1;
175 			/* XXX strtol() */
176 			pri = atoi(optarg);
177 			break;
178 
179 		case 's':
180 			SET_COMMAND(CMD_s);
181 			break;
182 
183 		case 't':
184 			if (tflag != NULL)
185 				usage();
186 			tflag = optarg;
187 			break;
188 
189 		default:
190 			usage();
191 			/* NOTREACHED */
192 		}
193 	}
194 
195 	/* Did the user specify a command? */
196 	if (command == 0)
197 		usage();
198 
199 	argv += optind;
200 	argc -= optind;
201 
202 	switch (argc) {
203 	case 0:
204 		if (command & REQUIRE_PATH)
205 			usage();
206 		break;
207 
208 	case 1:
209 		if (command & REQUIRE_NOPATH)
210 			usage();
211 		break;
212 
213 	default:
214 		usage();
215 	}
216 
217 	/* To change priority, you have to specify one. */
218 	if ((command == CMD_c) && pflag == 0)
219 		usage();
220 
221 	/* Sanity-check -t */
222 	if (tflag != NULL) {
223 		if (command != CMD_A)
224 			usage();
225 		if (strcmp(tflag, "blk") != 0 &&
226 		    strcmp(tflag, "noblk") != 0)
227 			usage();
228 	}
229 
230 	/* Dispatch the command. */
231 	switch (command) {
232 	case CMD_l:
233 		list_swap(pri, kflag, pflag, 0, 1);
234 		break;
235 
236 	case CMD_s:
237 		list_swap(pri, kflag, pflag, 0, 0);
238 		break;
239 
240 	case CMD_c:
241 		change_priority(argv[0]);
242 		break;
243 
244 	case CMD_a:
245 		add_swap(argv[0]);
246 		break;
247 
248 	case CMD_d:
249 		delete_swap(argv[0]);
250 		break;
251 
252 	case CMD_A:
253 		do_fstab();
254 		break;
255 
256 	case CMD_D:
257 		set_dumpdev(argv[0]);
258 		break;
259 	}
260 
261 	exit(0);
262 }
263 
264 /*
265  * swapon_command: emulate the old swapon(8) program.
266  */
267 void
268 swapon_command(argc, argv)
269 	int argc;
270 	char **argv;
271 {
272 	int ch, fiztab = 0;
273 
274 	while ((ch = getopt(argc, argv, "at:")) != -1) {
275 		switch (ch) {
276 		case 'a':
277 			fiztab = 1;
278 			break;
279 		case 't':
280 			if (tflag != NULL)
281 				usage();
282 			tflag = optarg;
283 			break;
284 		default:
285 			goto swapon_usage;
286 		}
287 	}
288 	argc -= optind;
289 	argv += optind;
290 
291 	if (fiztab) {
292 		if (argc)
293 			goto swapon_usage;
294 		/* Sanity-check -t */
295 		if (tflag != NULL) {
296 			if (strcmp(tflag, "blk") != 0 &&
297 			    strcmp(tflag, "noblk") != 0)
298 				usage();
299 		}
300 		do_fstab();
301 		exit(0);
302 	} else if (argc == 0 || tflag != NULL)
303 		goto swapon_usage;
304 
305 	while (argc) {
306 		add_swap(argv[0]);
307 		argc--;
308 		argv++;
309 	}
310 	exit(0);
311 	/* NOTREACHED */
312 
313  swapon_usage:
314 	fprintf(stderr, "usage: %s -a [-t blk|noblk]\n", __progname);
315 	fprintf(stderr, "       %s <path> ...\n", __progname);
316 	exit(1);
317 }
318 
319 /*
320  * change_priority:  change the priority of a swap device.
321  */
322 void
323 change_priority(path)
324 	const char	*path;
325 {
326 
327 	if (swapctl(SWAP_CTL, path, pri) < 0)
328 		warn("%s", path);
329 }
330 
331 /*
332  * add_swap:  add the pathname to the list of swap devices.
333  */
334 void
335 add_swap(path)
336 	const char *path;
337 {
338 	struct stat sb;
339 
340 	if (stat(path, &sb) < 0)
341 		goto oops;
342 
343 	if (sb.st_mode & S_IROTH)
344 		warnx("%s is readable by the world", path);
345 	if (sb.st_mode & S_IWOTH)
346 		warnx("%s is writable by the world", path);
347 
348 	if (swapctl(SWAP_ON, path, pri) < 0)
349 oops:
350 		err(1, "%s", path);
351 }
352 
353 /*
354  * delete_swap:  remove the pathname to the list of swap devices.
355  */
356 void
357 delete_swap(path)
358 	const char *path;
359 {
360 
361 	if (swapctl(SWAP_OFF, path, pri) < 0)
362 		err(1, "%s", path);
363 }
364 
365 void
366 set_dumpdev(path)
367 	const char *path;
368 {
369 
370 	if (swapctl(SWAP_DUMPDEV, path, NULL) == -1)
371 		warn("could not set dump device to %s", path);
372 	else
373 		printf("%s: setting dump device to %s\n", __progname, path);
374 }
375 
376 void
377 do_fstab()
378 {
379 	struct	fstab *fp;
380 	char	*s;
381 	long	priority;
382 	struct	stat st;
383 	int	isblk;
384 	int	gotone = 0;
385 
386 #define PRIORITYEQ	"priority="
387 #define NFSMNTPT	"nfsmntpt="
388 #define PATH_MOUNT	"/sbin/mount_nfs"
389 	while ((fp = getfsent()) != NULL) {
390 		const char *spec;
391 
392 		spec = fp->fs_spec;
393 
394 		if (strcmp(fp->fs_type, "dp") == 0) {
395 			set_dumpdev(spec);
396 			continue;
397 		}
398 
399 		if (strcmp(fp->fs_type, "sw") != 0)
400 			continue;
401 		isblk = 0;
402 
403 		if ((s = strstr(fp->fs_mntops, PRIORITYEQ)) != NULL) {
404 			s += sizeof(PRIORITYEQ) - 1;
405 			priority = atol(s);
406 		} else
407 			priority = pri;
408 
409 		if ((s = strstr(fp->fs_mntops, NFSMNTPT)) != NULL) {
410 			char *t, cmd[2*PATH_MAX+sizeof(PATH_MOUNT)+2];
411 
412 			/*
413 			 * Skip this song and dance if we're only
414 			 * doing block devices.
415 			 */
416 			if (tflag != NULL &&
417 			    strcmp(tflag, "blk") == 0)
418 				continue;
419 
420 			t = strpbrk(s, ",");
421 			if (t != 0)
422 				*t = '\0';
423 			spec = strdup(s + strlen(NFSMNTPT));
424 			if (t != 0)
425 				*t = ',';
426 
427 			if (spec == NULL)
428 				errx(1, "Out of memory");
429 
430 			if (strlen(spec) == 0) {
431 				warnx("empty mountpoint");
432 				free((char *)spec);
433 				continue;
434 			}
435 			snprintf(cmd, sizeof(cmd), "%s %s %s",
436 				PATH_MOUNT, fp->fs_spec, spec);
437 			if (system(cmd) != 0) {
438 				warnx("%s: mount failed", fp->fs_spec);
439 				continue;
440 			}
441 		} else {
442 			/*
443 			 * Determine blk-ness.
444 			 */
445 			if (stat(spec, &st) < 0) {
446 				warn(spec);
447 				continue;
448 			}
449 			if (S_ISBLK(st.st_mode))
450 				isblk = 1;
451 		}
452 
453 		/*
454 		 * Skip this type if we're told to.
455 		 */
456 		if (tflag != NULL) {
457 			if (strcmp(tflag, "blk") == 0 && isblk == 0)
458 				continue;
459 			if (strcmp(tflag, "noblk") == 0 && isblk == 1)
460 				continue;
461 		}
462 
463 		if (swapctl(SWAP_ON, spec, (int)priority) < 0)
464 			warn("%s", spec);
465 		else {
466 			gotone = 1;
467 			printf("%s: adding %s as swap device at priority %d\n",
468 			    __progname, fp->fs_spec, (int)priority);
469 		}
470 
471 		if (spec != fp->fs_spec)
472 			free((char *)spec);
473 	}
474 	if (gotone == 0)
475 		exit(1);
476 }
477 
478 void
479 usage()
480 {
481 
482 	fprintf(stderr, "usage: %s -A [-p priority] [-t blk|noblk]\n",
483 	    __progname);
484 	fprintf(stderr, "       %s -D dumppath\n", __progname);
485 	fprintf(stderr, "       %s -a [-p priority] path\n", __progname);
486 	fprintf(stderr, "       %s -c -p priority path\n", __progname);
487 	fprintf(stderr, "       %s -d path\n", __progname);
488 	fprintf(stderr, "       %s -l | -s [-k]\n", __progname);
489 	exit(1);
490 }
491