swapctl.c revision 1.2 
1/*	$OpenBSD: swapctl.c,v 1.2 2000/02/26 04:06:23 hugh Exp $	*/
2/*	$NetBSD: swapctl.c,v 1.9 1998/07/26 20:23:15 mycroft Exp $	*/
3
4/*
5 * Copyright (c) 1996, 1997 Matthew R. Green
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 3. The name of the author may not be used to endorse or promote products
17 *    derived from this software without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
24 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
25 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
26 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
27 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32/*
33 * swapctl command:
34 *	-A		add all devices listed as `sw' in /etc/fstab
35 *	-t [blk|noblk]	if -A, add either all block device or all non-block
36 *			devices
37 *	-a <dev>	add this device
38 *	-d <dev>	remove this swap device (not supported yet)
39 *	-l		list swap devices
40 *	-s		short listing of swap devices
41 *	-k		use kilobytes
42 *	-p <pri>	use this priority
43 *	-c		change priority
44 *
45 * or, if invoked as "swapon" (compatibility mode):
46 *
47 *	-a		all devices listed as `sw' in /etc/fstab
48 *	-t		same as -t above (feature not present in old
49 *			swapon(8) command)
50 *	<dev>		add this device
51 */
52
53#include <sys/param.h>
54#include <sys/stat.h>
55
56#include <sys/swap.h>
57
58#include <unistd.h>
59#include <err.h>
60#include <errno.h>
61#include <stdio.h>
62#include <stdlib.h>
63#include <string.h>
64#include <fstab.h>
65
66#include "swapctl.h"
67
68int	command;
69
70/*
71 * Commands for swapctl(8).  These are mutually exclusive.
72 */
73#define	CMD_A		0x01	/* process /etc/fstab */
74#define	CMD_a		0x02	/* add a swap file/device */
75#define	CMD_c		0x04	/* change priority of a swap file/device */
76#define	CMD_d		0x08	/* delete a swap file/device */
77#define	CMD_l		0x10	/* list swap files/devices */
78#define	CMD_s		0x20	/* summary of swap files/devices */
79
80#define	SET_COMMAND(cmd) \
81do { \
82	if (command) \
83		usage(); \
84	command = (cmd); \
85} while (0)
86
87/*
88 * Commands that require a "path" argument at the end of the command
89 * line, and the ones which require that none exist.
90 */
91#define	REQUIRE_PATH	(CMD_a | CMD_c | CMD_d)
92#define	REQUIRE_NOPATH	(CMD_A | CMD_l | CMD_s)
93
94/*
95 * Option flags, and the commands with which they are valid.
96 */
97int	kflag;		/* display in 1K blocks */
98#define	KFLAG_CMDS	(CMD_l | CMD_s)
99
100int	pflag;		/* priority was specified */
101#define	PFLAG_CMDS	(CMD_A | CMD_a | CMD_c)
102
103char	*tflag;		/* swap device type (blk or noblk) */
104#define	TFLAG_CMDS	(CMD_A)
105
106int	pri;		/* uses 0 as default pri */
107
108static	void change_priority __P((char *));
109static	void add_swap __P((char *));
110static	void del_swap __P((char *));
111	int  main __P((int, char *[]));
112static	void do_fstab __P((void));
113static	void usage __P((void));
114static	void swapon_command __P((int, char **));
115#if 0
116static	void swapoff_command __P((int, char **));
117#endif
118
119extern	char *__progname;	/* from crt0.o */
120
121int
122main(argc, argv)
123	int	argc;
124	char	*argv[];
125{
126	int	c;
127
128	if (strcmp(__progname, "swapon") == 0) {
129		swapon_command(argc, argv);
130		/* NOTREACHED */
131	}
132
133#if 0
134	if (strcmp(__progname, "swapoff") == 0) {
135		swapoff_command(argc, argv);
136		/* NOTREACHED */
137	}
138#endif
139
140	while ((c = getopt(argc, argv, "Aacdlkp:st:")) != -1) {
141		switch (c) {
142		case 'A':
143			SET_COMMAND(CMD_A);
144			break;
145
146		case 'a':
147			SET_COMMAND(CMD_a);
148			break;
149
150		case 'c':
151			SET_COMMAND(CMD_c);
152			break;
153
154		case 'd':
155			SET_COMMAND(CMD_d);
156			break;
157
158		case 'l':
159			SET_COMMAND(CMD_l);
160			break;
161
162		case 'k':
163			kflag = 1;
164			break;
165
166		case 'p':
167			pflag = 1;
168			/* XXX strtol() */
169			pri = atoi(optarg);
170			break;
171
172		case 's':
173			SET_COMMAND(CMD_s);
174			break;
175
176		case 't':
177			if (tflag != NULL)
178				usage();
179			tflag = optarg;
180			break;
181
182		default:
183			usage();
184			/* NOTREACHED */
185		}
186	}
187
188	/* Did the user specify a command? */
189	if (command == 0)
190		usage();
191
192	argv += optind;
193	argc -= optind;
194
195	switch (argc) {
196	case 0:
197		if (command & REQUIRE_PATH)
198			usage();
199		break;
200
201	case 1:
202		if (command & REQUIRE_NOPATH)
203			usage();
204		break;
205
206	default:
207		usage();
208	}
209
210	/* To change priority, you have to specify one. */
211	if ((command == CMD_c) && pflag == 0)
212		usage();
213
214	/* Sanity-check -t */
215	if (tflag != NULL) {
216		if (command != CMD_A)
217			usage();
218		if (strcmp(tflag, "blk") != 0 &&
219		    strcmp(tflag, "noblk") != 0)
220			usage();
221	}
222
223	/* Dispatch the command. */
224	switch (command) {
225	case CMD_l:
226		list_swap(pri, kflag, pflag, 0, 1);
227		break;
228
229	case CMD_s:
230		list_swap(pri, kflag, pflag, 0, 0);
231		break;
232
233	case CMD_c:
234		change_priority(argv[0]);
235		break;
236
237	case CMD_a:
238		add_swap(argv[0]);
239		break;
240
241	case CMD_d:
242		del_swap(argv[0]);
243		break;
244
245	case CMD_A:
246		do_fstab();
247		break;
248	}
249
250	exit(0);
251}
252
253/*
254 * swapon_command: emulate the old swapon(8) program.
255 */
256void
257swapon_command(argc, argv)
258	int argc;
259	char **argv;
260{
261	int ch, fiztab = 0;
262
263	while ((ch = getopt(argc, argv, "at:")) != -1) {
264		switch (ch) {
265		case 'a':
266			fiztab = 1;
267			break;
268		case 't':
269			if (tflag != NULL)
270				usage();
271			tflag = optarg;
272			break;
273		default:
274			goto swapon_usage;
275		}
276	}
277	argc -= optind;
278	argv += optind;
279
280	if (fiztab) {
281		if (argc)
282			goto swapon_usage;
283		/* Sanity-check -t */
284		if (tflag != NULL) {
285			if (strcmp(tflag, "blk") != 0 &&
286			    strcmp(tflag, "noblk") != 0)
287				usage();
288		}
289		do_fstab();
290		exit(0);
291	} else if (argc == 0 || tflag != NULL)
292		goto swapon_usage;
293
294	while (argc) {
295		add_swap(argv[0]);
296		argc--;
297		argv++;
298	}
299	exit(0);
300	/* NOTREACHED */
301
302 swapon_usage:
303	fprintf(stderr, "usage: %s -a [-t blk|noblk]\n", __progname);
304	fprintf(stderr, "       %s <path> ...\n", __progname);
305	exit(1);
306}
307
308/*
309 * change_priority:  change the priority of a swap device.
310 */
311void
312change_priority(path)
313	char	*path;
314{
315
316	if (swapctl(SWAP_CTL, path, pri) < 0)
317		warn("%s", path);
318}
319
320/*
321 * add_swap:  add the pathname to the list of swap devices.
322 */
323void
324add_swap(path)
325	char *path;
326{
327
328	if (swapctl(SWAP_ON, path, pri) < 0)
329		err(1, "%s", path);
330}
331
332/*
333 * del_swap:  remove the pathname to the list of swap devices.
334 */
335void
336del_swap(path)
337	char *path;
338{
339
340	if (swapctl(SWAP_OFF, path, pri) < 0)
341		err(1, "%s", path);
342}
343
344void
345do_fstab()
346{
347	struct	fstab *fp;
348	char	*s;
349	long	priority;
350	struct	stat st;
351	int	isblk;
352	int	gotone = 0;
353
354#define PRIORITYEQ	"priority="
355#define NFSMNTPT	"nfsmntpt="
356#define PATH_MOUNT	"/sbin/mount_nfs"
357	while ((fp = getfsent()) != NULL) {
358		const char *spec;
359
360		if (strcmp(fp->fs_type, "sw") != 0)
361			continue;
362
363		spec = fp->fs_spec;
364		isblk = 0;
365
366		if ((s = strstr(fp->fs_mntops, PRIORITYEQ)) != NULL) {
367			s += sizeof(PRIORITYEQ) - 1;
368			priority = atol(s);
369		} else
370			priority = pri;
371
372		if ((s = strstr(fp->fs_mntops, NFSMNTPT)) != NULL) {
373			char *t, cmd[2*PATH_MAX+sizeof(PATH_MOUNT)+2];
374
375			/*
376			 * Skip this song and dance if we're only
377			 * doing block devices.
378			 */
379			if (tflag != NULL &&
380			    strcmp(tflag, "blk") == 0)
381				continue;
382
383			t = strpbrk(s, ",");
384			if (t != 0)
385				*t = '\0';
386			spec = strdup(s + strlen(NFSMNTPT));
387			if (t != 0)
388				*t = ',';
389
390			if (spec == NULL)
391				errx(1, "Out of memory");
392
393			if (strlen(spec) == 0) {
394				warnx("empty mountpoint");
395				free((char *)spec);
396				continue;
397			}
398			snprintf(cmd, sizeof(cmd), "%s %s %s",
399				PATH_MOUNT, fp->fs_spec, spec);
400			if (system(cmd) != 0) {
401				warnx("%s: mount failed", fp->fs_spec);
402				continue;
403			}
404		} else {
405			/*
406			 * Determine blk-ness.
407			 */
408			if (stat(spec, &st) < 0) {
409				warn(spec);
410				continue;
411			}
412			if (S_ISBLK(st.st_mode))
413				isblk = 1;
414		}
415
416		/*
417		 * Skip this type if we're told to.
418		 */
419		if (tflag != NULL) {
420			if (strcmp(tflag, "blk") == 0 && isblk == 0)
421				continue;
422			if (strcmp(tflag, "noblk") == 0 && isblk == 1)
423				continue;
424		}
425
426		if (swapctl(SWAP_ON, spec, (int)priority) < 0)
427			warn("%s", spec);
428		else {
429			gotone = 1;
430			printf("%s: adding %s as swap device at priority %d\n",
431			    __progname, fp->fs_spec, (int)priority);
432		}
433
434		if (spec != fp->fs_spec)
435			free((char *)spec);
436	}
437	if (gotone == 0)
438		exit(1);
439}
440
441void
442usage()
443{
444
445	fprintf(stderr, "usage: %s -A [-p priority] [-t blk|noblk]\n",
446	    __progname);
447	fprintf(stderr, "       %s -a [-p priority] path\n", __progname);
448	fprintf(stderr, "       %s -c -p priority path\n", __progname);
449	fprintf(stderr, "       %s -d path\n", __progname);
450	fprintf(stderr, "       %s -l | -s [-k]\n", __progname);
451	exit(1);
452}
453