Home | History | Annotate | Line # | Download | only in swapctl
swapctl.c revision 1.4 
      1 /*	$NetBSD: swapctl.c,v 1.4 1997/06/25 23:18:11 thorpej Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1996, 1997 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. All advertising materials mentioning features or use of this software
     16  *    must display the following acknowledgement:
     17  *      This product includes software developed by Matthew R. Green for
     18  *      The NetBSD Foundation.
     19  * 4. The name of the author may not be used to endorse or promote products
     20  *    derived from this software without specific prior written permission.
     21  *
     22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
     27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
     28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
     29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
     30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     32  * SUCH DAMAGE.
     33  */
     34 
     35 /*
     36  * swapctl command:
     37  *	-A		add all devices listed as `sw' in /etc/fstab
     38  *	-t [blk|noblk]	if -A, add either all block device or all non-block
     39  *			devices
     40  *	-a <dev>	add this device
     41  *	-d <dev>	remove this swap device (not supported yet)
     42  *	-l		list swap devices
     43  *	-s		short listing of swap devices
     44  *	-k		use kilobytes
     45  *	-p <pri>	use this priority
     46  *	-c		change priority
     47  *
     48  * or, if invoked as "swapon" (compatibility mode):
     49  *
     50  *	-a		all devices listed as `sw' in /etc/fstab
     51  *	-t		same as -t above (feature not present in old
     52  *			swapon(8) command)
     53  *	<dev>		add this device
     54  */
     55 
     56 #include <sys/param.h>
     57 #include <sys/stat.h>
     58 
     59 #include <vm/vm_swap.h>
     60 
     61 #include <unistd.h>
     62 #include <err.h>
     63 #include <errno.h>
     64 #include <stdio.h>
     65 #include <stdlib.h>
     66 #include <string.h>
     67 #include <fstab.h>
     68 
     69 #include "swapctl.h"
     70 
     71 int	command;
     72 
     73 /*
     74  * Commands for swapctl(8).  These are mutually exclusive.
     75  */
     76 #define	CMD_A		0x01	/* process /etc/fstab */
     77 #define	CMD_a		0x02	/* add a swap file/device */
     78 #define	CMD_c		0x04	/* change priority of a swap file/device */
     79 #define	CMD_d		0x08	/* delete a swap file/device */
     80 #define	CMD_l		0x10	/* list swap files/devices */
     81 #define	CMD_s		0x20	/* summary of swap files/devices */
     82 
     83 #define	SET_COMMAND(cmd) \
     84 do { \
     85 	if (command) \
     86 		usage(); \
     87 	command = (cmd); \
     88 } while (0)
     89 
     90 /*
     91  * Commands that require a "path" argument at the end of the command
     92  * line, and the ones which require that none exist.
     93  */
     94 #define	REQUIRE_PATH	(CMD_a | CMD_c | CMD_d)
     95 #define	REQUIRE_NOPATH	(CMD_A | CMD_l | CMD_s)
     96 
     97 /*
     98  * Option flags, and the commands with which they are valid.
     99  */
    100 int	kflag;		/* display in 1K blocks */
    101 #define	KFLAG_CMDS	(CMD_l | CMD_s)
    102 
    103 int	pflag;		/* priority was specified */
    104 #define	PFLAG_CMDS	(CMD_A | CMD_a | CMD_c)
    105 
    106 char	*tflag;		/* swap device type (blk or noblk) */
    107 #define	TFLAG_CMDS	(CMD_A)
    108 
    109 int	pri;		/* uses 0 as default pri */
    110 
    111 static	void change_priority __P((char *));
    112 static	void add_swap __P((char *));
    113 static	void del_swap __P((char *));
    114 static	void do_fstab __P((void));
    115 static	void usage __P((void));
    116 static	void swapon_command __P((int, char **));
    117 #if 0
    118 static	void swapoff_command __P((int, char **));
    119 #endif
    120 
    121 extern	char *__progname;	/* from crt0.o */
    122 
    123 int
    124 main(argc, argv)
    125 	int	argc;
    126 	char	*argv[];
    127 {
    128 	int	c;
    129 
    130 	if (strcmp(__progname, "swapon") == 0) {
    131 		swapon_command(argc, argv);
    132 		/* NOTREACHED */
    133 	}
    134 
    135 #if 0
    136 	if (strcmp(__progname, "swapoff") == 0) {
    137 		swapoff_command(argc, argv);
    138 		/* NOTREACHED */
    139 	}
    140 #endif
    141 
    142 	while ((c = getopt(argc, argv, "Aacdlkp:st:")) != -1) {
    143 		switch (c) {
    144 		case 'A':
    145 			SET_COMMAND(CMD_A);
    146 			break;
    147 
    148 		case 'a':
    149 			SET_COMMAND(CMD_a);
    150 			break;
    151 
    152 		case 'c':
    153 			SET_COMMAND(CMD_c);
    154 			break;
    155 
    156 		case 'd':
    157 			SET_COMMAND(CMD_d);
    158 			break;
    159 
    160 		case 'l':
    161 			SET_COMMAND(CMD_l);
    162 			break;
    163 
    164 		case 'k':
    165 			kflag = 1;
    166 			break;
    167 
    168 		case 'p':
    169 			pflag = 1;
    170 			/* XXX strtol() */
    171 			pri = atoi(optarg);
    172 			break;
    173 
    174 		case 's':
    175 			SET_COMMAND(CMD_s);
    176 			break;
    177 
    178 		case 't':
    179 			if (tflag != NULL)
    180 				usage();
    181 			tflag = optarg;
    182 			break;
    183 
    184 		default:
    185 			usage();
    186 			/* NOTREACHED */
    187 		}
    188 	}
    189 
    190 	/* Did the user specify a command? */
    191 	if (command == 0)
    192 		usage();
    193 
    194 	argv += optind;
    195 	argc -= optind;
    196 
    197 	switch (argc) {
    198 	case 0:
    199 		if (command & REQUIRE_PATH)
    200 			usage();
    201 		break;
    202 
    203 	case 1:
    204 		if (command & REQUIRE_NOPATH)
    205 			usage();
    206 		break;
    207 
    208 	default:
    209 		usage();
    210 	}
    211 
    212 	/* To change priority, you have to specify one. */
    213 	if ((command == CMD_c) && pflag == 0)
    214 		usage();
    215 
    216 	/* Sanity-check -t */
    217 	if (tflag != NULL) {
    218 		if (command != CMD_A)
    219 			usage();
    220 		if (strcmp(tflag, "blk") != 0 &&
    221 		    strcmp(tflag, "noblk") != 0)
    222 			usage();
    223 	}
    224 
    225 	/* Dispatch the command. */
    226 	switch (command) {
    227 	case CMD_l:
    228 		list_swap(pri, kflag, pflag, 0, 1);
    229 		break;
    230 
    231 	case CMD_s:
    232 		list_swap(pri, kflag, pflag, 0, 0);
    233 		break;
    234 
    235 	case CMD_c:
    236 		change_priority(argv[0]);
    237 		break;
    238 
    239 	case CMD_a:
    240 		add_swap(argv[0]);
    241 		break;
    242 
    243 	case CMD_d:
    244 		del_swap(argv[0]);
    245 		break;
    246 
    247 	case CMD_A:
    248 		do_fstab();
    249 		break;
    250 	}
    251 
    252 	exit(0);
    253 }
    254 
    255 /*
    256  * swapon_command: emulate the old swapon(8) program.
    257  */
    258 void
    259 swapon_command(argc, argv)
    260 	int argc;
    261 	char **argv;
    262 {
    263 	int ch, fiztab = 0;
    264 
    265 	while ((ch = getopt(argc, argv, "at:")) != -1) {
    266 		switch (ch) {
    267 		case 'a':
    268 			fiztab = 1;
    269 			break;
    270 		case 't':
    271 			if (tflag != NULL)
    272 				usage();
    273 			tflag = optarg;
    274 			break;
    275 		default:
    276 			goto swapon_usage;
    277 		}
    278 	}
    279 	argc -= optind;
    280 	argv += optind;
    281 
    282 	if (fiztab) {
    283 		if (argc)
    284 			goto swapon_usage;
    285 		/* Sanity-check -t */
    286 		if (tflag != NULL) {
    287 			if (strcmp(tflag, "blk") != 0 &&
    288 			    strcmp(tflag, "noblk") != 0)
    289 				usage();
    290 		}
    291 		do_fstab();
    292 		exit(0);
    293 	} else if (argc == 0 || tflag != NULL)
    294 		goto swapon_usage;
    295 
    296 	while (argc) {
    297 		add_swap(argv[0]);
    298 		argc--;
    299 		argv++;
    300 	}
    301 	exit(0);
    302 	/* NOTREACHED */
    303 
    304  swapon_usage:
    305 	fprintf(stderr, "usage: %s -a [-t blk|noblk]\n", __progname);
    306 	fprintf(stderr, "       %s <path> ...\n", __progname);
    307 	exit(1);
    308 }
    309 
    310 /*
    311  * change_priority:  change the priority of a swap device.
    312  */
    313 void
    314 change_priority(path)
    315 	char	*path;
    316 {
    317 
    318 	if (swapctl(SWAP_CTL, path, pri) < 0)
    319 		warn("%s", path);
    320 }
    321 
    322 /*
    323  * add_swap:  add the pathname to the list of swap devices.
    324  */
    325 void
    326 add_swap(path)
    327 	char *path;
    328 {
    329 
    330 	if (swapctl(SWAP_ON, path, pri) < 0)
    331 		err(1, "%s", path);
    332 }
    333 
    334 /*
    335  * del_swap:  remove the pathname to the list of swap devices.
    336  */
    337 void
    338 del_swap(path)
    339 	char *path;
    340 {
    341 
    342 	if (swapctl(SWAP_OFF, path, pri) < 0)
    343 		err(1, "%s", path);
    344 }
    345 
    346 void
    347 do_fstab()
    348 {
    349 	struct	fstab *fp;
    350 	char	*s;
    351 	long	priority;
    352 	struct	stat st;
    353 	int	isblk;
    354 
    355 #define PRIORITYEQ	"priority="
    356 #define NFSMNTPT	"nfsmntpt="
    357 #define PATH_MOUNT	"/sbin/mount_nfs"
    358 	while ((fp = getfsent())) {
    359 		char *spec;
    360 
    361 		if (strcmp(fp->fs_type, "sw") != 0)
    362 			continue;
    363 
    364 		spec = fp->fs_spec;
    365 		isblk = 0;
    366 
    367 		if ((s = strstr(fp->fs_mntops, PRIORITYEQ))) {
    368 			s += sizeof(PRIORITYEQ) - 1;
    369 			priority = atol(s);
    370 		} else
    371 			priority = pri;
    372 
    373 		if ((s = strstr(fp->fs_mntops, NFSMNTPT))) {
    374 			char *t, cmd[2*PATH_MAX+sizeof(PATH_MOUNT)+2];
    375 
    376 			/*
    377 			 * Skip this song and dance if we're only
    378 			 * doing block devices.
    379 			 */
    380 			if (tflag != NULL &&
    381 			    strcmp(tflag, "blk") == 0)
    382 				continue;
    383 
    384 			t = strpbrk(s, ",");
    385 			if (t != 0)
    386 				*t = '\0';
    387 			spec = strdup(s + strlen(NFSMNTPT));
    388 			if (t != 0)
    389 				*t = ',';
    390 
    391 			if (spec == NULL)
    392 				errx(1, "Out of memory");
    393 
    394 			if (strlen(spec) == 0) {
    395 				warnx("empty mountpoint");
    396 				free(spec);
    397 				continue;
    398 			}
    399 			snprintf(cmd, sizeof(cmd), "%s %s %s",
    400 				PATH_MOUNT, fp->fs_spec, spec);
    401 			if (system(cmd) != 0) {
    402 				warnx("%s: mount failed", fp->fs_spec);
    403 				continue;
    404 			}
    405 		} else {
    406 			/*
    407 			 * Determine blk-ness.
    408 			 */
    409 			if (stat(spec, &st) < 0) {
    410 				warn(spec);
    411 				continue;
    412 			}
    413 			if (S_ISBLK(st.st_mode))
    414 				isblk = 1;
    415 		}
    416 
    417 		/*
    418 		 * Skip this type if we're told to.
    419 		 */
    420 		if (tflag != NULL) {
    421 			if (strcmp(tflag, "blk") == 0 && isblk == 0)
    422 				continue;
    423 			if (strcmp(tflag, "noblk") == 0 && isblk == 1)
    424 				continue;
    425 		}
    426 
    427 		if (swapctl(SWAP_ON, spec, (int)priority) < 0)
    428 			warn("%s", spec);
    429 		else
    430 			printf("%s: adding %s as swap device at priority %d\n",
    431 			    __progname, fp->fs_spec, (int)priority);
    432 
    433 		if (spec != fp->fs_spec)
    434 			free(spec);
    435 	}
    436 }
    437 
    438 void
    439 usage()
    440 {
    441 
    442 	fprintf(stderr, "usage: %s -A [-p priority] [-t blk|noblk]\n",
    443 	    __progname);
    444 	fprintf(stderr, "       %s -a [-p priority] path\n", __progname);
    445 	fprintf(stderr, "       %s -c -p priority path\n", __progname);
    446 	fprintf(stderr, "       %s -d path\n", __progname);
    447 	fprintf(stderr, "       %s -l | -s [-k]\n", __progname);
    448 	exit(1);
    449 }
    450