d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
cdd530ca19
freebsd-dev/sbin/sysctl/sysctl.c
Luigi Rizzo 60cf2c1254 Export a (machine dependent) kernel variable bootdev as 
machdep.guessed_bootdev, and add code to sysctl to parse its value
and give a (not necessarily correct) name to the device we booted
from (the main motivation for this code is to use the info in the
PicoBSD boot scripts, and the impact on the kernel is minimal).

NOTE: the information available in bootdev is not always reliable,
so you should not trust it too much.  The parsing code is the same
as in boot2.c, and cannot cover all cases -- as it is, it seems to
work fine with floppies and IDE disks recognised by the BIOS. It
_should_ work as well with SCSI disks recognised by the BIOS.
Booting from a CDROM in floppy emulation will return /dev/fd0 (because
this is what the BIOS tells us).
Booting off the network (e.g. with etherboot) leaves bootdev unset so
the value will be printed as "invalid (0xffffffff)".

Finally, this feature might go away at some point, hopefully when we
have a more reliable way to get the same information.

MFC-after: 5 days
2002-03-10 20:08:44 +00:00

646 lines
14 KiB
C
Raw Blame History

/*
* Copyright (c) 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef lint
static const char copyright[] =
"@(#) Copyright (c) 1993\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)from: sysctl.c 8.1 (Berkeley) 6/6/93";
#endif
static const char rcsid[] =
"$FreeBSD$";
#endif /* not lint */
#include <sys/diskslice.h> /* used for bootdev parsing */
#include <sys/param.h>
#include <sys/time.h>
#include <sys/reboot.h> /* used for bootdev parsing */
#include <sys/resource.h>
#include <sys/stat.h>
#include <sys/sysctl.h>
#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
static int aflag, bflag, dflag, eflag, Nflag, nflag, oflag, xflag;
static int oidfmt(int *, int, char *, u_int *);
static void parse(char *);
static int show_var(int *, int);
static int sysctl_all (int *oid, int len);
static int name2oid(char *, int *);
static void set_T_dev_t (char *, void **, int *);
static void
usage(void)
{
(void)fprintf(stderr, "%s\n%s\n",
"usage: sysctl [-bdeNnox] variable[=value] ...",
" sysctl [-bdeNnox] -a");
exit(1);
}
int
main(int argc, char **argv)
{
int ch;
setbuf(stdout,0);
setbuf(stderr,0);
while ((ch = getopt(argc, argv, "AabdeNnowxX")) != -1) {
switch (ch) {
case 'A':
/* compatibility */
aflag = oflag = 1;
break;
case 'a':
aflag = 1;
break;
case 'b':
bflag = 1;
break;
case 'd':
dflag = 1;
break;
case 'e':
eflag = 1;
break;
case 'N':
Nflag = 1;
break;
case 'n':
nflag = 1;
break;
case 'o':
oflag = 1;
break;
case 'w':
/* compatibility */
/* ignored */
break;
case 'X':
/* compatibility */
aflag = xflag = 1;
break;
case 'x':
xflag = 1;
break;
default:
usage();
}
}
argc -= optind;
argv += optind;
if (Nflag && nflag)
usage();
if (aflag && argc == 0)
exit(sysctl_all(0, 0));
if (argc == 0)
usage();
while (argc-- > 0)
parse(*argv++);
exit(0);
}
/*
* Parse a name into a MIB entry.
* Lookup and print out the MIB entry if it exists.
* Set a new value if requested.
*/
static void
parse(char *string)
{
int len, i, j;
void *newval = 0;
int intval;
unsigned int uintval;
long longval;
unsigned long ulongval;
size_t newsize = 0;
quad_t quadval;
int mib[CTL_MAXNAME];
char *cp, *bufp, buf[BUFSIZ], fmt[BUFSIZ];
u_int kind;
bufp = buf;
snprintf(buf, BUFSIZ, "%s", string);
if ((cp = strchr(string, '=')) != NULL) {
*strchr(buf, '=') = '\0';
*cp++ = '\0';
while (isspace(*cp))
cp++;
newval = cp;
newsize = strlen(cp);
}
len = name2oid(bufp, mib);
if (len < 0)
errx(1, "unknown oid '%s'", bufp);
if (oidfmt(mib, len, fmt, &kind))
err(1, "couldn't find format of oid '%s'", bufp);
if (newval == NULL) {
if ((kind & CTLTYPE) == CTLTYPE_NODE) {
sysctl_all(mib, len);
} else {
i = show_var(mib, len);
if (!i && !bflag)
putchar('\n');
}
} else {
if ((kind & CTLTYPE) == CTLTYPE_NODE)
errx(1, "oid '%s' isn't a leaf node", bufp);
if (!(kind&CTLFLAG_WR))
errx(1, "oid '%s' is read only", bufp);
switch (kind & CTLTYPE) {
case CTLTYPE_INT:
intval = (int) strtol(newval, NULL, 0);
newval = &intval;
newsize = sizeof(intval);
break;
case CTLTYPE_UINT:
uintval = (int) strtoul(newval, NULL, 0);
newval = &uintval;
newsize = sizeof uintval;
break;
case CTLTYPE_LONG:
longval = strtol(newval, NULL, 0);
newval = &longval;
newsize = sizeof longval;
break;
case CTLTYPE_ULONG:
ulongval = strtoul(newval, NULL, 0);
newval = &ulongval;
newsize = sizeof ulongval;
break;
case CTLTYPE_STRING:
break;
case CTLTYPE_QUAD:
sscanf(newval, "%qd", &quadval);
newval = &quadval;
newsize = sizeof(quadval);
break;
case CTLTYPE_OPAQUE:
if (strcmp(fmt, "T,dev_t") == 0) {
set_T_dev_t ((char*)newval, &newval, &newsize);
break;
}
/* FALLTHROUGH */
default:
errx(1, "oid '%s' is type %d,"
" cannot set that", bufp,
kind & CTLTYPE);
}
i = show_var(mib, len);
if (sysctl(mib, len, 0, 0, newval, newsize) == -1) {
if (!i && !bflag)
putchar('\n');
switch (errno) {
case EOPNOTSUPP:
errx(1, "%s: value is not available",
string);
case ENOTDIR:
errx(1, "%s: specification is incomplete",
string);
case ENOMEM:
errx(1, "%s: type is unknown to this program",
string);
default:
warn("%s", string);
return;
}
}
if (!bflag)
printf(" -> ");
i = nflag;
nflag = 1;
j = show_var(mib, len);
if (!j && !bflag)
putchar('\n');
nflag = i;
}
}
/* These functions will dump out various interesting structures. */
static int
S_clockinfo(int l2, void *p)
{
struct clockinfo *ci = (struct clockinfo*)p;
if (l2 != sizeof(*ci))
err(1, "S_clockinfo %d != %d", l2, sizeof(*ci));
printf("{ hz = %d, tick = %d, tickadj = %d, profhz = %d, stathz = %d }",
ci->hz, ci->tick, ci->tickadj, ci->profhz, ci->stathz);
return (0);
}
static int
S_loadavg(int l2, void *p)
{
struct loadavg *tv = (struct loadavg*)p;
if (l2 != sizeof(*tv))
err(1, "S_loadavg %d != %d", l2, sizeof(*tv));
printf("{ %.2f %.2f %.2f }",
(double)tv->ldavg[0]/(double)tv->fscale,
(double)tv->ldavg[1]/(double)tv->fscale,
(double)tv->ldavg[2]/(double)tv->fscale);
return (0);
}
static int
S_timeval(int l2, void *p)
{
struct timeval *tv = (struct timeval*)p;
time_t tv_sec;
char *p1, *p2;
if (l2 != sizeof(*tv))
err(1, "S_timeval %d != %d", l2, sizeof(*tv));
printf("{ sec = %ld, usec = %ld } ",
tv->tv_sec, tv->tv_usec);
tv_sec = tv->tv_sec;
p1 = strdup(ctime(&tv_sec));
for (p2=p1; *p2 ; p2++)
if (*p2 == '\n')
*p2 = '\0';
fputs(p1, stdout);
return (0);
}
static int
T_dev_t(int l2, void *p)
{
dev_t *d = (dev_t *)p;
if (l2 != sizeof(*d))
err(1, "T_dev_T %d != %d", l2, sizeof(*d));
if ((int)(*d) != -1) {
if (minor(*d) > 255 || minor(*d) < 0)
printf("{ major = %d, minor = 0x%x }",
major(*d), minor(*d));
else
printf("{ major = %d, minor = %d }",
major(*d), minor(*d));
}
return (0);
}
static void
set_T_dev_t (char *path, void **val, int *size)
{
static struct stat statb;
if (strcmp(path, "none") && strcmp(path, "off")) {
int rc = stat (path, &statb);
if (rc) {
err(1, "cannot stat %s", path);
}
if (!S_ISCHR(statb.st_mode)) {
errx(1, "must specify a device special file.");
}
} else {
statb.st_rdev = NODEV;
}
*val = (char*) &statb.st_rdev;
*size = sizeof statb.st_rdev;
}
/*
* These functions uses a presently undocumented interface to the kernel
* to walk the tree and get the type so it can print the value.
* This interface is under work and consideration, and should probably
* be killed with a big axe by the first person who can find the time.
* (be aware though, that the proper interface isn't as obvious as it
* may seem, there are various conflicting requirements.
*/
static int
name2oid(char *name, int *oidp)
{
int oid[2];
int i;
size_t j;
oid[0] = 0;
oid[1] = 3;
j = CTL_MAXNAME * sizeof(int);
i = sysctl(oid, 2, oidp, &j, name, strlen(name));
if (i < 0)
return i;
j /= sizeof(int);
return (j);
}
static int
oidfmt(int *oid, int len, char *fmt, u_int *kind)
{
int qoid[CTL_MAXNAME+2];
u_char buf[BUFSIZ];
int i;
size_t j;
qoid[0] = 0;
qoid[1] = 4;
memcpy(qoid + 2, oid, len * sizeof(int));
j = sizeof(buf);
i = sysctl(qoid, len + 2, buf, &j, 0, 0);
if (i)
err(1, "sysctl fmt %d %d %d", i, j, errno);
if (kind)
*kind = *(u_int *)buf;
if (fmt)
strcpy(fmt, (char *)(buf + sizeof(u_int)));
return 0;
}
/*
* Code to map a bootdev major number into a suitable device name.
* Major numbers are mapped into names as in boot2.c
*/
struct _foo {
int majdev;
char *name;
} maj2name[] = {
30, "ad",
0, "wd",
1, "wfd",
2, "fd",
4, "da",
-1, NULL /* terminator */
};
static int
machdep_bootdev(u_long value)
{
int majdev, unit, slice, part;
struct _foo *p;
if (value & B_MAGICMASK != B_DEVMAGIC) {
printf("invalid (0x%08x)", value);
return 0;
}
majdev = B_TYPE(value);
unit = B_UNIT(value);
slice = B_SLICE(value);
part = B_PARTITION(value);
if (majdev == 2) { /* floppy, as known to the boot block... */
printf("/dev/fd%d", unit);
return 0;
}
for (p = maj2name; p->name != NULL && p->majdev != majdev ; p++) ;
if (p->name != NULL) { /* found */
if (slice == WHOLE_DISK_SLICE)
printf("/dev/%s%d%c", p->name, unit, part);
else
printf("/dev/%s%ds%d%c",
p->name, unit, slice - BASE_SLICE + 1, part + 'a');
} else
printf("unknown (major %d unit %d slice %d part %d)",
majdev, unit, slice, part);
return 0;
}
/*
* This formats and outputs the value of one variable
*
* Returns zero if anything was actually output.
* Returns one if didn't know what to do with this.
* Return minus one if we had errors.
*/
static int
show_var(int *oid, int nlen)
{
u_char buf[BUFSIZ], *val, *p;
char name[BUFSIZ], *fmt, *sep;
int qoid[CTL_MAXNAME+2];
int i;
size_t j, len;
u_int kind;
int (*func)(int, void *);
qoid[0] = 0;
memcpy(qoid + 2, oid, nlen * sizeof(int));
qoid[1] = 1;
j = sizeof(name);
i = sysctl(qoid, nlen + 2, name, &j, 0, 0);
if (i || !j)
err(1, "sysctl name %d %d %d", i, j, errno);
if (Nflag) {
printf("%s", name);
return (0);
}
if (eflag)
sep = "=";
else
sep = ": ";
if (dflag) { /* just print description */
qoid[1] = 5;
j = sizeof(buf);
i = sysctl(qoid, nlen + 2, buf, &j, 0, 0);
if (!nflag)
printf("%s%s", name, sep);
printf("%s", buf);
return (0);
}
/* find an estimate of how much we need for this var */
j = 0;
i = sysctl(oid, nlen, 0, &j, 0, 0);
j += j; /* we want to be sure :-) */
val = alloca(j);
len = j;
i = sysctl(oid, nlen, val, &len, 0, 0);
if (i || !len)
return (1);
if (bflag) {
fwrite(val, 1, len, stdout);
return (0);
}
fmt = buf;
oidfmt(oid, nlen, fmt, &kind);
p = val;
switch (*fmt) {
case 'A':
if (!nflag)
printf("%s%s", name, sep);
printf("%s", p);
return (0);
case 'I':
if (!nflag)
printf("%s%s", name, sep);
fmt++;
val = "";
while (len >= sizeof(int)) {
if(*fmt == 'U')
printf("%s%u", val, *(unsigned int *)p);
else
printf("%s%d", val, *(int *)p);
val = " ";
len -= sizeof(int);
p += sizeof(int);
}
return (0);
case 'L':
if (!nflag)
printf("%s%s", name, sep);
fmt++;
if (!strcmp(name, "machdep.guessed_bootdev"))
return machdep_bootdev(*(unsigned long *)p);
val = "";
while (len >= sizeof(long)) {
if(*fmt == 'U')
printf("%s%lu", val, *(unsigned long *)p);
else
printf("%s%ld", val, *(long *)p);
val = " ";
len -= sizeof(long);
p += sizeof(long);
}
return (0);
case 'P':
if (!nflag)
printf("%s%s", name, sep);
printf("%p", *(void **)p);
return (0);
case 'T':
case 'S':
i = 0;
if (strcmp(fmt, "S,clockinfo") == 0)
func = S_clockinfo;
else if (strcmp(fmt, "S,timeval") == 0)
func = S_timeval;
else if (strcmp(fmt, "S,loadavg") == 0)
func = S_loadavg;
else if (strcmp(fmt, "T,dev_t") == 0)
func = T_dev_t;
else
func = NULL;
if (func) {
if (!nflag)
printf("%s%s", name, sep);
return ((*func)(len, p));
}
/* FALL THROUGH */
default:
if (!oflag && !xflag)
return (1);
if (!nflag)
printf("%s%s", name, sep);
printf("Format:%s Length:%d Dump:0x", fmt, len);
while (len-- && (xflag || p < val + 16))
printf("%02x", *p++);
if (!xflag && len > 16)
printf("...");
return (0);
}
return (1);
}
static int
sysctl_all (int *oid, int len)
{
int name1[22], name2[22];
int i, j;
size_t l1, l2;
name1[0] = 0;
name1[1] = 2;
l1 = 2;
if (len) {
memcpy(name1+2, oid, len * sizeof(int));
l1 += len;
} else {
name1[2] = 1;
l1++;
}
for (;;) {
l2 = sizeof(name2);
j = sysctl(name1, l1, name2, &l2, 0, 0);
if (j < 0) {
if (errno == ENOENT)
return 0;
else
err(1, "sysctl(getnext) %d %d", j, l2);
}
l2 /= sizeof(int);
if (l2 < len)
return 0;
for (i = 0; i < len; i++)
if (name2[i] != oid[i])
return 0;
i = show_var(name2, l2);
if (!i && !bflag)
putchar('\n');
memcpy(name1+2, name2, l2 * sizeof(int));
l1 = 2 + l2;
}
}
Reference in New Issue View Git Blame Copy Permalink