xref: /freebsd/sbin/sysctl/sysctl.c (revision 7660b554bc59a07be0431c17e0e33815818baa69)
1 /*
2  * Copyright (c) 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  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 static const char copyright[] =
36 "@(#) Copyright (c) 1993\n\
37 	The Regents of the University of California.  All rights reserved.\n";
38 #endif /* not lint */
39 
40 #ifndef lint
41 #if 0
42 static char sccsid[] = "@(#)from: sysctl.c	8.1 (Berkeley) 6/6/93";
43 #endif
44 static const char rcsid[] =
45   "$FreeBSD$";
46 #endif /* not lint */
47 
48 #ifdef __i386__
49 #include <sys/reboot.h>		/* used for bootdev parsing */
50 #endif
51 #include <sys/param.h>
52 #include <sys/time.h>
53 #include <sys/resource.h>
54 #include <sys/stat.h>
55 #include <sys/sysctl.h>
56 #include <sys/vmmeter.h>
57 
58 #include <ctype.h>
59 #include <err.h>
60 #include <errno.h>
61 #include <stdio.h>
62 #include <stdlib.h>
63 #include <string.h>
64 #include <unistd.h>
65 
66 static int	aflag, bflag, dflag, eflag, Nflag, nflag, oflag, xflag;
67 
68 static int	oidfmt(int *, int, char *, u_int *);
69 static void	parse(char *);
70 static int	show_var(int *, int);
71 static int	sysctl_all (int *oid, int len);
72 static int	name2oid(char *, int *);
73 
74 static void	set_T_dev_t (char *, void **, int *);
75 
76 static void
77 usage(void)
78 {
79 
80 	(void)fprintf(stderr, "%s\n%s\n",
81 	    "usage: sysctl [-bdeNnox] variable[=value] ...",
82 	    "       sysctl [-bdeNnox] -a");
83 	exit(1);
84 }
85 
86 int
87 main(int argc, char **argv)
88 {
89 	int ch;
90 	setbuf(stdout,0);
91 	setbuf(stderr,0);
92 
93 	while ((ch = getopt(argc, argv, "AabdeNnowxX")) != -1) {
94 		switch (ch) {
95 		case 'A':
96 			/* compatibility */
97 			aflag = oflag = 1;
98 			break;
99 		case 'a':
100 			aflag = 1;
101 			break;
102 		case 'b':
103 			bflag = 1;
104 			break;
105 		case 'd':
106 			dflag = 1;
107 			break;
108 		case 'e':
109 			eflag = 1;
110 			break;
111 		case 'N':
112 			Nflag = 1;
113 			break;
114 		case 'n':
115 			nflag = 1;
116 			break;
117 		case 'o':
118 			oflag = 1;
119 			break;
120 		case 'w':
121 			/* compatibility */
122 			/* ignored */
123 			break;
124 		case 'X':
125 			/* compatibility */
126 			aflag = xflag = 1;
127 			break;
128 		case 'x':
129 			xflag = 1;
130 			break;
131 		default:
132 			usage();
133 		}
134 	}
135 	argc -= optind;
136 	argv += optind;
137 
138 	if (Nflag && nflag)
139 		usage();
140 	if (aflag && argc == 0)
141 		exit(sysctl_all(0, 0));
142 	if (argc == 0)
143 		usage();
144 	while (argc-- > 0)
145 		parse(*argv++);
146 	exit(0);
147 }
148 
149 /*
150  * Parse a name into a MIB entry.
151  * Lookup and print out the MIB entry if it exists.
152  * Set a new value if requested.
153  */
154 static void
155 parse(char *string)
156 {
157 	int len, i, j;
158 	void *newval = 0;
159 	int intval;
160 	unsigned int uintval;
161 	long longval;
162 	unsigned long ulongval;
163 	size_t newsize = 0;
164 	quad_t quadval;
165 	int mib[CTL_MAXNAME];
166 	char *cp, *bufp, buf[BUFSIZ], *endptr, fmt[BUFSIZ];
167 	u_int kind;
168 
169 	bufp = buf;
170 	snprintf(buf, BUFSIZ, "%s", string);
171 	if ((cp = strchr(string, '=')) != NULL) {
172 		*strchr(buf, '=') = '\0';
173 		*cp++ = '\0';
174 		while (isspace(*cp))
175 			cp++;
176 		newval = cp;
177 		newsize = strlen(cp);
178 	}
179 	len = name2oid(bufp, mib);
180 
181 	if (len < 0)
182 		errx(1, "unknown oid '%s'", bufp);
183 
184 	if (oidfmt(mib, len, fmt, &kind))
185 		err(1, "couldn't find format of oid '%s'", bufp);
186 
187 	if (newval == NULL) {
188 		if ((kind & CTLTYPE) == CTLTYPE_NODE) {
189 			sysctl_all(mib, len);
190 		} else {
191 			i = show_var(mib, len);
192 			if (!i && !bflag)
193 				putchar('\n');
194 		}
195 	} else {
196 		if ((kind & CTLTYPE) == CTLTYPE_NODE)
197 			errx(1, "oid '%s' isn't a leaf node", bufp);
198 
199 		if (!(kind&CTLFLAG_WR))
200 			errx(1, "oid '%s' is read only", bufp);
201 
202 		if ((kind & CTLTYPE) == CTLTYPE_INT ||
203 		    (kind & CTLTYPE) == CTLTYPE_UINT ||
204 		    (kind & CTLTYPE) == CTLTYPE_LONG ||
205 		    (kind & CTLTYPE) == CTLTYPE_ULONG) {
206 			if (strlen(newval) == 0)
207 				errx(1, "empty numeric value");
208 		}
209 
210 		switch (kind & CTLTYPE) {
211 			case CTLTYPE_INT:
212 				intval = (int) strtol(newval, &endptr, 0);
213 				if (endptr == newval || *endptr != '\0')
214 					errx(1, "invalid integer '%s'",
215 					    newval);
216 				newval = &intval;
217 				newsize = sizeof(intval);
218 				break;
219 			case CTLTYPE_UINT:
220 				uintval = (int) strtoul(newval, &endptr, 0);
221 				if (endptr == newval || *endptr != '\0')
222 					errx(1, "invalid unsigned integer '%s'",
223 					    newval);
224 				newval = &uintval;
225 				newsize = sizeof uintval;
226 				break;
227 			case CTLTYPE_LONG:
228 				longval = strtol(newval, &endptr, 0);
229 				if (endptr == newval || *endptr != '\0')
230 					errx(1, "invalid long integer '%s'",
231 					    newval);
232 				newval = &longval;
233 				newsize = sizeof longval;
234 				break;
235 			case CTLTYPE_ULONG:
236 				ulongval = strtoul(newval, &endptr, 0);
237 				if (endptr == newval || *endptr != '\0')
238 					errx(1, "invalid unsigned long integer"
239 					    " '%s'", newval);
240 				newval = &ulongval;
241 				newsize = sizeof ulongval;
242 				break;
243 			case CTLTYPE_STRING:
244 				break;
245 			case CTLTYPE_QUAD:
246 				sscanf(newval, "%qd", &quadval);
247 				newval = &quadval;
248 				newsize = sizeof(quadval);
249 				break;
250 			case CTLTYPE_OPAQUE:
251 				if (strcmp(fmt, "T,dev_t") == 0) {
252 					set_T_dev_t ((char*)newval, &newval, &newsize);
253 					break;
254 				}
255 				/* FALLTHROUGH */
256 			default:
257 				errx(1, "oid '%s' is type %d,"
258 					" cannot set that", bufp,
259 					kind & CTLTYPE);
260 		}
261 
262 		i = show_var(mib, len);
263 		if (sysctl(mib, len, 0, 0, newval, newsize) == -1) {
264 			if (!i && !bflag)
265 				putchar('\n');
266 			switch (errno) {
267 			case EOPNOTSUPP:
268 				errx(1, "%s: value is not available",
269 					string);
270 			case ENOTDIR:
271 				errx(1, "%s: specification is incomplete",
272 					string);
273 			case ENOMEM:
274 				errx(1, "%s: type is unknown to this program",
275 					string);
276 			default:
277 				warn("%s", string);
278 				return;
279 			}
280 		}
281 		if (!bflag)
282 			printf(" -> ");
283 		i = nflag;
284 		nflag = 1;
285 		j = show_var(mib, len);
286 		if (!j && !bflag)
287 			putchar('\n');
288 		nflag = i;
289 	}
290 }
291 
292 /* These functions will dump out various interesting structures. */
293 
294 static int
295 S_clockinfo(int l2, void *p)
296 {
297 	struct clockinfo *ci = (struct clockinfo*)p;
298 	if (l2 != sizeof(*ci)) {
299 		warnx("S_clockinfo %d != %d", l2, sizeof(*ci));
300 		return (0);
301 	}
302 	printf("{ hz = %d, tick = %d, profhz = %d, stathz = %d }",
303 		ci->hz, ci->tick, ci->profhz, ci->stathz);
304 	return (0);
305 }
306 
307 static int
308 S_loadavg(int l2, void *p)
309 {
310 	struct loadavg *tv = (struct loadavg*)p;
311 
312 	if (l2 != sizeof(*tv)) {
313 		warnx("S_loadavg %d != %d", l2, sizeof(*tv));
314 		return (0);
315 	}
316 	printf("{ %.2f %.2f %.2f }",
317 		(double)tv->ldavg[0]/(double)tv->fscale,
318 		(double)tv->ldavg[1]/(double)tv->fscale,
319 		(double)tv->ldavg[2]/(double)tv->fscale);
320 	return (0);
321 }
322 
323 static int
324 S_timeval(int l2, void *p)
325 {
326 	struct timeval *tv = (struct timeval*)p;
327 	time_t tv_sec;
328 	char *p1, *p2;
329 
330 	if (l2 != sizeof(*tv)) {
331 		warnx("S_timeval %d != %d", l2, sizeof(*tv));
332 		return (0);
333 	}
334 	printf("{ sec = %ld, usec = %ld } ",
335 		tv->tv_sec, tv->tv_usec);
336 	tv_sec = tv->tv_sec;
337 	p1 = strdup(ctime(&tv_sec));
338 	for (p2=p1; *p2 ; p2++)
339 		if (*p2 == '\n')
340 			*p2 = '\0';
341 	fputs(p1, stdout);
342 	return (0);
343 }
344 
345 static int
346 S_vmtotal(int l2, void *p)
347 {
348 	struct vmtotal *v = (struct vmtotal *)p;
349 	int pageKilo = getpagesize() / 1024;
350 
351 	if (l2 != sizeof(*v)) {
352 		warnx("S_vmtotal %d != %d", l2, sizeof(*v));
353 		return (0);
354 	}
355 
356 	printf(
357 	    "\nSystem wide totals computed every five seconds:"
358 	    " (values in kilobytes)\n");
359 	printf("===============================================\n");
360 	printf(
361 	    "Processes:\t\t(RUNQ: %hu Disk Wait: %hu Page Wait: "
362 	    "%hu Sleep: %hu)\n",
363 	    v->t_rq, v->t_dw, v->t_pw, v->t_sl);
364 	printf(
365 	    "Virtual Memory:\t\t(Total: %luK, Active %lldK)\n",
366 	    (unsigned long)v->t_vm / 1024,
367 	    (long long)v->t_avm * pageKilo);
368 	printf("Real Memory:\t\t(Total: %lldK Active %lldK)\n",
369 	    (long long)v->t_rm * pageKilo, (long long)v->t_arm * pageKilo);
370 	printf("Shared Virtual Memory:\t(Total: %lldK Active: %lldK)\n",
371 	    (long long)v->t_vmshr * pageKilo,
372 	    (long long)v->t_avmshr * pageKilo);
373 	printf("Shared Real Memory:\t(Total: %lldK Active: %lldK)\n",
374 	    (long long)v->t_rmshr * pageKilo,
375 	    (long long)v->t_armshr * pageKilo);
376 	printf("Free Memory Pages:\t%ldK\n", (long long)v->t_free * pageKilo);
377 
378 	return (0);
379 }
380 
381 static int
382 T_dev_t(int l2, void *p)
383 {
384 	dev_t *d = (dev_t *)p;
385 	if (l2 != sizeof(*d)) {
386 		warnx("T_dev_T %d != %d", l2, sizeof(*d));
387 		return (0);
388 	}
389 	if ((int)(*d) != -1) {
390 		if (minor(*d) > 255 || minor(*d) < 0)
391 			printf("{ major = %d, minor = 0x%x }",
392 				major(*d), minor(*d));
393 		else
394 			printf("{ major = %d, minor = %d }",
395 				major(*d), minor(*d));
396 	}
397 	return (0);
398 }
399 
400 static void
401 set_T_dev_t (char *path, void **val, int *size)
402 {
403 	static struct stat statb;
404 
405 	if (strcmp(path, "none") && strcmp(path, "off")) {
406 		int rc = stat (path, &statb);
407 		if (rc) {
408 			err(1, "cannot stat %s", path);
409 		}
410 
411 		if (!S_ISCHR(statb.st_mode)) {
412 			errx(1, "must specify a device special file.");
413 		}
414 	} else {
415 		statb.st_rdev = NODEV;
416 	}
417 	*val = (char*) &statb.st_rdev;
418 	*size = sizeof statb.st_rdev;
419 }
420 
421 /*
422  * These functions uses a presently undocumented interface to the kernel
423  * to walk the tree and get the type so it can print the value.
424  * This interface is under work and consideration, and should probably
425  * be killed with a big axe by the first person who can find the time.
426  * (be aware though, that the proper interface isn't as obvious as it
427  * may seem, there are various conflicting requirements.
428  */
429 
430 static int
431 name2oid(char *name, int *oidp)
432 {
433 	int oid[2];
434 	int i;
435 	size_t j;
436 
437 	oid[0] = 0;
438 	oid[1] = 3;
439 
440 	j = CTL_MAXNAME * sizeof(int);
441 	i = sysctl(oid, 2, oidp, &j, name, strlen(name));
442 	if (i < 0)
443 		return i;
444 	j /= sizeof(int);
445 	return (j);
446 }
447 
448 static int
449 oidfmt(int *oid, int len, char *fmt, u_int *kind)
450 {
451 	int qoid[CTL_MAXNAME+2];
452 	u_char buf[BUFSIZ];
453 	int i;
454 	size_t j;
455 
456 	qoid[0] = 0;
457 	qoid[1] = 4;
458 	memcpy(qoid + 2, oid, len * sizeof(int));
459 
460 	j = sizeof(buf);
461 	i = sysctl(qoid, len + 2, buf, &j, 0, 0);
462 	if (i)
463 		err(1, "sysctl fmt %d %d %d", i, j, errno);
464 
465 	if (kind)
466 		*kind = *(u_int *)buf;
467 
468 	if (fmt)
469 		strcpy(fmt, (char *)(buf + sizeof(u_int)));
470 	return 0;
471 }
472 
473 /*
474  * This formats and outputs the value of one variable
475  *
476  * Returns zero if anything was actually output.
477  * Returns one if didn't know what to do with this.
478  * Return minus one if we had errors.
479  */
480 
481 static int
482 show_var(int *oid, int nlen)
483 {
484 	u_char buf[BUFSIZ], *val, *p;
485 	char name[BUFSIZ], *fmt, *sep;
486 	int qoid[CTL_MAXNAME+2];
487 	int i;
488 	size_t j, len;
489 	u_int kind;
490 	int (*func)(int, void *);
491 
492 	qoid[0] = 0;
493 	memcpy(qoid + 2, oid, nlen * sizeof(int));
494 
495 	qoid[1] = 1;
496 	j = sizeof(name);
497 	i = sysctl(qoid, nlen + 2, name, &j, 0, 0);
498 	if (i || !j)
499 		err(1, "sysctl name %d %d %d", i, j, errno);
500 
501 	if (Nflag) {
502 		printf("%s", name);
503 		return (0);
504 	}
505 
506 	if (eflag)
507 		sep = "=";
508 	else
509 		sep = ": ";
510 
511 	if (dflag) {	/* just print description */
512 		qoid[1] = 5;
513 		j = sizeof(buf);
514 		i = sysctl(qoid, nlen + 2, buf, &j, 0, 0);
515 		if (!nflag)
516 			printf("%s%s", name, sep);
517 		printf("%s", buf);
518 		return (0);
519 	}
520 	/* find an estimate of how much we need for this var */
521 	j = 0;
522 	i = sysctl(oid, nlen, 0, &j, 0, 0);
523 	j += j; /* we want to be sure :-) */
524 
525 	val = alloca(j + 1);
526 	len = j;
527 	i = sysctl(oid, nlen, val, &len, 0, 0);
528 	if (i || !len)
529 		return (1);
530 
531 	if (bflag) {
532 		fwrite(val, 1, len, stdout);
533 		return (0);
534 	}
535 	val[len] = '\0';
536 	fmt = buf;
537 	oidfmt(oid, nlen, fmt, &kind);
538 	p = val;
539 	switch (*fmt) {
540 	case 'A':
541 		if (!nflag)
542 			printf("%s%s", name, sep);
543 		printf("%.*s", len, p);
544 		return (0);
545 
546 	case 'I':
547 		if (!nflag)
548 			printf("%s%s", name, sep);
549 		fmt++;
550 		val = "";
551 		while (len >= sizeof(int)) {
552 			if(*fmt == 'U')
553 				printf("%s%u", val, *(unsigned int *)p);
554 			else
555 				printf("%s%d", val, *(int *)p);
556 			val = " ";
557 			len -= sizeof(int);
558 			p += sizeof(int);
559 		}
560 		return (0);
561 
562 	case 'L':
563 		if (!nflag)
564 			printf("%s%s", name, sep);
565 		fmt++;
566 		val = "";
567 		while (len >= sizeof(long)) {
568 			if(*fmt == 'U')
569 				printf("%s%lu", val, *(unsigned long *)p);
570 			else
571 				printf("%s%ld", val, *(long *)p);
572 			val = " ";
573 			len -= sizeof(long);
574 			p += sizeof(long);
575 		}
576 		return (0);
577 
578 	case 'P':
579 		if (!nflag)
580 			printf("%s%s", name, sep);
581 		printf("%p", *(void **)p);
582 		return (0);
583 
584 	case 'T':
585 	case 'S':
586 		i = 0;
587 		if (strcmp(fmt, "S,clockinfo") == 0)
588 			func = S_clockinfo;
589 		else if (strcmp(fmt, "S,timeval") == 0)
590 			func = S_timeval;
591 		else if (strcmp(fmt, "S,loadavg") == 0)
592 			func = S_loadavg;
593 		else if (strcmp(fmt, "S,vmtotal") == 0)
594 			func = S_vmtotal;
595 		else if (strcmp(fmt, "T,dev_t") == 0)
596 			func = T_dev_t;
597 		else
598 			func = NULL;
599 		if (func) {
600 			if (!nflag)
601 				printf("%s%s", name, sep);
602 			return ((*func)(len, p));
603 		}
604 		/* FALLTHROUGH */
605 	default:
606 		if (!oflag && !xflag)
607 			return (1);
608 		if (!nflag)
609 			printf("%s%s", name, sep);
610 		printf("Format:%s Length:%d Dump:0x", fmt, len);
611 		while (len-- && (xflag || p < val + 16))
612 			printf("%02x", *p++);
613 		if (!xflag && len > 16)
614 			printf("...");
615 		return (0);
616 	}
617 	return (1);
618 }
619 
620 static int
621 sysctl_all (int *oid, int len)
622 {
623 	int name1[22], name2[22];
624 	int i, j;
625 	size_t l1, l2;
626 
627 	name1[0] = 0;
628 	name1[1] = 2;
629 	l1 = 2;
630 	if (len) {
631 		memcpy(name1+2, oid, len * sizeof(int));
632 		l1 += len;
633 	} else {
634 		name1[2] = 1;
635 		l1++;
636 	}
637 	for (;;) {
638 		l2 = sizeof(name2);
639 		j = sysctl(name1, l1, name2, &l2, 0, 0);
640 		if (j < 0) {
641 			if (errno == ENOENT)
642 				return 0;
643 			else
644 				err(1, "sysctl(getnext) %d %d", j, l2);
645 		}
646 
647 		l2 /= sizeof(int);
648 
649 		if (l2 < len)
650 			return 0;
651 
652 		for (i = 0; i < len; i++)
653 			if (name2[i] != oid[i])
654 				return 0;
655 
656 		i = show_var(name2, l2);
657 		if (!i && !bflag)
658 			putchar('\n');
659 
660 		memcpy(name1+2, name2, l2 * sizeof(int));
661 		l1 = 2 + l2;
662 	}
663 }
664