freebsd-dev/sys/kern/subr_prf.c
Eric van Gyzen c207ff9319 Always send log(9) messages to the message buffer.
It is truer to the semantics of logging for messages to *always*
go to the message buffer, where they can eventually be collected
and, in fact, be put into a log file.

This restores the behavior prior to r70239, which seems to have
changed it inadvertently.

Submitted by:	Eric Badger <eric@badgerio.us>
Reviewed by:	jhb
Approved by:	kib (mentor)
Obtained from:	Dell Inc.
MFC after:	1 week
2015-04-20 20:03:26 +00:00

1122 lines
24 KiB
C

/*-
* Copyright (c) 1986, 1988, 1991, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* 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.
* 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.
*
* @(#)subr_prf.c 8.3 (Berkeley) 1/21/94
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_ddb.h"
#include "opt_printf.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/lock.h>
#include <sys/kdb.h>
#include <sys/mutex.h>
#include <sys/sx.h>
#include <sys/kernel.h>
#include <sys/msgbuf.h>
#include <sys/malloc.h>
#include <sys/priv.h>
#include <sys/proc.h>
#include <sys/stddef.h>
#include <sys/sysctl.h>
#include <sys/tty.h>
#include <sys/syslog.h>
#include <sys/cons.h>
#include <sys/uio.h>
#include <sys/ctype.h>
#ifdef DDB
#include <ddb/ddb.h>
#endif
/*
* Note that stdarg.h and the ANSI style va_start macro is used for both
* ANSI and traditional C compilers.
*/
#include <machine/stdarg.h>
#define TOCONS 0x01
#define TOTTY 0x02
#define TOLOG 0x04
/* Max number conversion buffer length: a u_quad_t in base 2, plus NUL byte. */
#define MAXNBUF (sizeof(intmax_t) * NBBY + 1)
struct putchar_arg {
int flags;
int pri;
struct tty *tty;
char *p_bufr;
size_t n_bufr;
char *p_next;
size_t remain;
};
struct snprintf_arg {
char *str;
size_t remain;
};
extern int log_open;
static void msglogchar(int c, int pri);
static void msglogstr(char *str, int pri, int filter_cr);
static void putchar(int ch, void *arg);
static char *ksprintn(char *nbuf, uintmax_t num, int base, int *len, int upper);
static void snprintf_func(int ch, void *arg);
static int msgbufmapped; /* Set when safe to use msgbuf */
int msgbuftrigger;
static int log_console_output = 1;
SYSCTL_INT(_kern, OID_AUTO, log_console_output, CTLFLAG_RWTUN,
&log_console_output, 0, "Duplicate console output to the syslog");
/*
* See the comment in log_console() below for more explanation of this.
*/
static int log_console_add_linefeed;
SYSCTL_INT(_kern, OID_AUTO, log_console_add_linefeed, CTLFLAG_RWTUN,
&log_console_add_linefeed, 0, "log_console() adds extra newlines");
static int always_console_output;
SYSCTL_INT(_kern, OID_AUTO, always_console_output, CTLFLAG_RWTUN,
&always_console_output, 0, "Always output to console despite TIOCCONS");
/*
* Warn that a system table is full.
*/
void
tablefull(const char *tab)
{
log(LOG_ERR, "%s: table is full\n", tab);
}
/*
* Uprintf prints to the controlling terminal for the current process.
*/
int
uprintf(const char *fmt, ...)
{
va_list ap;
struct putchar_arg pca;
struct proc *p;
struct thread *td;
int retval;
td = curthread;
if (TD_IS_IDLETHREAD(td))
return (0);
sx_slock(&proctree_lock);
p = td->td_proc;
PROC_LOCK(p);
if ((p->p_flag & P_CONTROLT) == 0) {
PROC_UNLOCK(p);
sx_sunlock(&proctree_lock);
return (0);
}
SESS_LOCK(p->p_session);
pca.tty = p->p_session->s_ttyp;
SESS_UNLOCK(p->p_session);
PROC_UNLOCK(p);
if (pca.tty == NULL) {
sx_sunlock(&proctree_lock);
return (0);
}
pca.flags = TOTTY;
pca.p_bufr = NULL;
va_start(ap, fmt);
tty_lock(pca.tty);
sx_sunlock(&proctree_lock);
retval = kvprintf(fmt, putchar, &pca, 10, ap);
tty_unlock(pca.tty);
va_end(ap);
return (retval);
}
/*
* tprintf and vtprintf print on the controlling terminal associated with the
* given session, possibly to the log as well.
*/
void
tprintf(struct proc *p, int pri, const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
vtprintf(p, pri, fmt, ap);
va_end(ap);
}
void
vtprintf(struct proc *p, int pri, const char *fmt, va_list ap)
{
struct tty *tp = NULL;
int flags = 0;
struct putchar_arg pca;
struct session *sess = NULL;
sx_slock(&proctree_lock);
if (pri != -1)
flags |= TOLOG;
if (p != NULL) {
PROC_LOCK(p);
if (p->p_flag & P_CONTROLT && p->p_session->s_ttyvp) {
sess = p->p_session;
sess_hold(sess);
PROC_UNLOCK(p);
tp = sess->s_ttyp;
if (tp != NULL && tty_checkoutq(tp))
flags |= TOTTY;
else
tp = NULL;
} else
PROC_UNLOCK(p);
}
pca.pri = pri;
pca.tty = tp;
pca.flags = flags;
pca.p_bufr = NULL;
if (pca.tty != NULL)
tty_lock(pca.tty);
sx_sunlock(&proctree_lock);
kvprintf(fmt, putchar, &pca, 10, ap);
if (pca.tty != NULL)
tty_unlock(pca.tty);
if (sess != NULL)
sess_release(sess);
msgbuftrigger = 1;
}
/*
* Ttyprintf displays a message on a tty; it should be used only by
* the tty driver, or anything that knows the underlying tty will not
* be revoke(2)'d away. Other callers should use tprintf.
*/
int
ttyprintf(struct tty *tp, const char *fmt, ...)
{
va_list ap;
struct putchar_arg pca;
int retval;
va_start(ap, fmt);
pca.tty = tp;
pca.flags = TOTTY;
pca.p_bufr = NULL;
retval = kvprintf(fmt, putchar, &pca, 10, ap);
va_end(ap);
return (retval);
}
static int
_vprintf(int level, int flags, const char *fmt, va_list ap)
{
struct putchar_arg pca;
int retval;
#ifdef PRINTF_BUFR_SIZE
char bufr[PRINTF_BUFR_SIZE];
#endif
pca.tty = NULL;
pca.pri = level;
pca.flags = flags;
#ifdef PRINTF_BUFR_SIZE
pca.p_bufr = bufr;
pca.p_next = pca.p_bufr;
pca.n_bufr = sizeof(bufr);
pca.remain = sizeof(bufr);
*pca.p_next = '\0';
#else
/* Don't buffer console output. */
pca.p_bufr = NULL;
#endif
retval = kvprintf(fmt, putchar, &pca, 10, ap);
#ifdef PRINTF_BUFR_SIZE
/* Write any buffered console/log output: */
if (*pca.p_bufr != '\0') {
if (pca.flags & TOLOG)
msglogstr(pca.p_bufr, level, /*filter_cr*/1);
if (pca.flags & TOCONS)
cnputs(pca.p_bufr);
}
#endif
return (retval);
}
/*
* Log writes to the log buffer, and guarantees not to sleep (so can be
* called by interrupt routines). If there is no process reading the
* log yet, it writes to the console also.
*/
void
log(int level, const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
(void)_vprintf(level, log_open ? TOLOG : TOCONS | TOLOG, fmt, ap);
va_end(ap);
msgbuftrigger = 1;
}
#define CONSCHUNK 128
void
log_console(struct uio *uio)
{
int c, error, nl;
char *consbuffer;
int pri;
if (!log_console_output)
return;
pri = LOG_INFO | LOG_CONSOLE;
uio = cloneuio(uio);
consbuffer = malloc(CONSCHUNK, M_TEMP, M_WAITOK);
nl = 0;
while (uio->uio_resid > 0) {
c = imin(uio->uio_resid, CONSCHUNK - 1);
error = uiomove(consbuffer, c, uio);
if (error != 0)
break;
/* Make sure we're NUL-terminated */
consbuffer[c] = '\0';
if (consbuffer[c - 1] == '\n')
nl = 1;
else
nl = 0;
msglogstr(consbuffer, pri, /*filter_cr*/ 1);
}
/*
* The previous behavior in log_console() is preserved when
* log_console_add_linefeed is non-zero. For that behavior, if an
* individual console write came in that was not terminated with a
* line feed, it would add a line feed.
*
* This results in different data in the message buffer than
* appears on the system console (which doesn't add extra line feed
* characters).
*
* A number of programs and rc scripts write a line feed, or a period
* and a line feed when they have completed their operation. On
* the console, this looks seamless, but when displayed with
* 'dmesg -a', you wind up with output that looks like this:
*
* Updating motd:
* .
*
* On the console, it looks like this:
* Updating motd:.
*
* We could add logic to detect that situation, or just not insert
* the extra newlines. Set the kern.log_console_add_linefeed
* sysctl/tunable variable to get the old behavior.
*/
if (!nl && log_console_add_linefeed) {
consbuffer[0] = '\n';
consbuffer[1] = '\0';
msglogstr(consbuffer, pri, /*filter_cr*/ 1);
}
msgbuftrigger = 1;
free(uio, M_IOV);
free(consbuffer, M_TEMP);
return;
}
int
printf(const char *fmt, ...)
{
va_list ap;
int retval;
va_start(ap, fmt);
retval = vprintf(fmt, ap);
va_end(ap);
return (retval);
}
int
vprintf(const char *fmt, va_list ap)
{
int retval;
retval = _vprintf(-1, TOCONS | TOLOG, fmt, ap);
if (!panicstr)
msgbuftrigger = 1;
return (retval);
}
static void
putbuf(int c, struct putchar_arg *ap)
{
/* Check if no console output buffer was provided. */
if (ap->p_bufr == NULL) {
/* Output direct to the console. */
if (ap->flags & TOCONS)
cnputc(c);
if (ap->flags & TOLOG)
msglogchar(c, ap->pri);
} else {
/* Buffer the character: */
*ap->p_next++ = c;
ap->remain--;
/* Always leave the buffer zero terminated. */
*ap->p_next = '\0';
/* Check if the buffer needs to be flushed. */
if (ap->remain == 2 || c == '\n') {
if (ap->flags & TOLOG)
msglogstr(ap->p_bufr, ap->pri, /*filter_cr*/1);
if (ap->flags & TOCONS) {
if ((panicstr == NULL) && (constty != NULL))
msgbuf_addstr(&consmsgbuf, -1,
ap->p_bufr, /*filter_cr*/ 0);
if ((constty == NULL) ||(always_console_output))
cnputs(ap->p_bufr);
}
ap->p_next = ap->p_bufr;
ap->remain = ap->n_bufr;
*ap->p_next = '\0';
}
/*
* Since we fill the buffer up one character at a time,
* this should not happen. We should always catch it when
* ap->remain == 2 (if not sooner due to a newline), flush
* the buffer and move on. One way this could happen is
* if someone sets PRINTF_BUFR_SIZE to 1 or something
* similarly silly.
*/
KASSERT(ap->remain > 2, ("Bad buffer logic, remain = %zd",
ap->remain));
}
}
/*
* Print a character on console or users terminal. If destination is
* the console then the last bunch of characters are saved in msgbuf for
* inspection later.
*/
static void
putchar(int c, void *arg)
{
struct putchar_arg *ap = (struct putchar_arg*) arg;
struct tty *tp = ap->tty;
int flags = ap->flags;
/* Don't use the tty code after a panic or while in ddb. */
if (kdb_active) {
if (c != '\0')
cnputc(c);
return;
}
if ((flags & TOTTY) && tp != NULL && panicstr == NULL)
tty_putchar(tp, c);
if ((flags & (TOCONS | TOLOG)) && c != '\0')
putbuf(c, ap);
}
/*
* Scaled down version of sprintf(3).
*/
int
sprintf(char *buf, const char *cfmt, ...)
{
int retval;
va_list ap;
va_start(ap, cfmt);
retval = kvprintf(cfmt, NULL, (void *)buf, 10, ap);
buf[retval] = '\0';
va_end(ap);
return (retval);
}
/*
* Scaled down version of vsprintf(3).
*/
int
vsprintf(char *buf, const char *cfmt, va_list ap)
{
int retval;
retval = kvprintf(cfmt, NULL, (void *)buf, 10, ap);
buf[retval] = '\0';
return (retval);
}
/*
* Scaled down version of snprintf(3).
*/
int
snprintf(char *str, size_t size, const char *format, ...)
{
int retval;
va_list ap;
va_start(ap, format);
retval = vsnprintf(str, size, format, ap);
va_end(ap);
return(retval);
}
/*
* Scaled down version of vsnprintf(3).
*/
int
vsnprintf(char *str, size_t size, const char *format, va_list ap)
{
struct snprintf_arg info;
int retval;
info.str = str;
info.remain = size;
retval = kvprintf(format, snprintf_func, &info, 10, ap);
if (info.remain >= 1)
*info.str++ = '\0';
return (retval);
}
/*
* Kernel version which takes radix argument vsnprintf(3).
*/
int
vsnrprintf(char *str, size_t size, int radix, const char *format, va_list ap)
{
struct snprintf_arg info;
int retval;
info.str = str;
info.remain = size;
retval = kvprintf(format, snprintf_func, &info, radix, ap);
if (info.remain >= 1)
*info.str++ = '\0';
return (retval);
}
static void
snprintf_func(int ch, void *arg)
{
struct snprintf_arg *const info = arg;
if (info->remain >= 2) {
*info->str++ = ch;
info->remain--;
}
}
/*
* Put a NUL-terminated ASCII number (base <= 36) in a buffer in reverse
* order; return an optional length and a pointer to the last character
* written in the buffer (i.e., the first character of the string).
* The buffer pointed to by `nbuf' must have length >= MAXNBUF.
*/
static char *
ksprintn(char *nbuf, uintmax_t num, int base, int *lenp, int upper)
{
char *p, c;
p = nbuf;
*p = '\0';
do {
c = hex2ascii(num % base);
*++p = upper ? toupper(c) : c;
} while (num /= base);
if (lenp)
*lenp = p - nbuf;
return (p);
}
/*
* Scaled down version of printf(3).
*
* Two additional formats:
*
* The format %b is supported to decode error registers.
* Its usage is:
*
* printf("reg=%b\n", regval, "<base><arg>*");
*
* where <base> is the output base expressed as a control character, e.g.
* \10 gives octal; \20 gives hex. Each arg is a sequence of characters,
* the first of which gives the bit number to be inspected (origin 1), and
* the next characters (up to a control character, i.e. a character <= 32),
* give the name of the register. Thus:
*
* kvprintf("reg=%b\n", 3, "\10\2BITTWO\1BITONE");
*
* would produce output:
*
* reg=3<BITTWO,BITONE>
*
* XXX: %D -- Hexdump, takes pointer and separator string:
* ("%6D", ptr, ":") -> XX:XX:XX:XX:XX:XX
* ("%*D", len, ptr, " " -> XX XX XX XX ...
*/
int
kvprintf(char const *fmt, void (*func)(int, void*), void *arg, int radix, va_list ap)
{
#define PCHAR(c) {int cc=(c); if (func) (*func)(cc,arg); else *d++ = cc; retval++; }
char nbuf[MAXNBUF];
char *d;
const char *p, *percent, *q;
u_char *up;
int ch, n;
uintmax_t num;
int base, lflag, qflag, tmp, width, ladjust, sharpflag, neg, sign, dot;
int cflag, hflag, jflag, tflag, zflag;
int dwidth, upper;
char padc;
int stop = 0, retval = 0;
num = 0;
if (!func)
d = (char *) arg;
else
d = NULL;
if (fmt == NULL)
fmt = "(fmt null)\n";
if (radix < 2 || radix > 36)
radix = 10;
for (;;) {
padc = ' ';
width = 0;
while ((ch = (u_char)*fmt++) != '%' || stop) {
if (ch == '\0')
return (retval);
PCHAR(ch);
}
percent = fmt - 1;
qflag = 0; lflag = 0; ladjust = 0; sharpflag = 0; neg = 0;
sign = 0; dot = 0; dwidth = 0; upper = 0;
cflag = 0; hflag = 0; jflag = 0; tflag = 0; zflag = 0;
reswitch: switch (ch = (u_char)*fmt++) {
case '.':
dot = 1;
goto reswitch;
case '#':
sharpflag = 1;
goto reswitch;
case '+':
sign = 1;
goto reswitch;
case '-':
ladjust = 1;
goto reswitch;
case '%':
PCHAR(ch);
break;
case '*':
if (!dot) {
width = va_arg(ap, int);
if (width < 0) {
ladjust = !ladjust;
width = -width;
}
} else {
dwidth = va_arg(ap, int);
}
goto reswitch;
case '0':
if (!dot) {
padc = '0';
goto reswitch;
}
case '1': case '2': case '3': case '4':
case '5': case '6': case '7': case '8': case '9':
for (n = 0;; ++fmt) {
n = n * 10 + ch - '0';
ch = *fmt;
if (ch < '0' || ch > '9')
break;
}
if (dot)
dwidth = n;
else
width = n;
goto reswitch;
case 'b':
num = (u_int)va_arg(ap, int);
p = va_arg(ap, char *);
for (q = ksprintn(nbuf, num, *p++, NULL, 0); *q;)
PCHAR(*q--);
if (num == 0)
break;
for (tmp = 0; *p;) {
n = *p++;
if (num & (1 << (n - 1))) {
PCHAR(tmp ? ',' : '<');
for (; (n = *p) > ' '; ++p)
PCHAR(n);
tmp = 1;
} else
for (; *p > ' '; ++p)
continue;
}
if (tmp)
PCHAR('>');
break;
case 'c':
PCHAR(va_arg(ap, int));
break;
case 'D':
up = va_arg(ap, u_char *);
p = va_arg(ap, char *);
if (!width)
width = 16;
while(width--) {
PCHAR(hex2ascii(*up >> 4));
PCHAR(hex2ascii(*up & 0x0f));
up++;
if (width)
for (q=p;*q;q++)
PCHAR(*q);
}
break;
case 'd':
case 'i':
base = 10;
sign = 1;
goto handle_sign;
case 'h':
if (hflag) {
hflag = 0;
cflag = 1;
} else
hflag = 1;
goto reswitch;
case 'j':
jflag = 1;
goto reswitch;
case 'l':
if (lflag) {
lflag = 0;
qflag = 1;
} else
lflag = 1;
goto reswitch;
case 'n':
if (jflag)
*(va_arg(ap, intmax_t *)) = retval;
else if (qflag)
*(va_arg(ap, quad_t *)) = retval;
else if (lflag)
*(va_arg(ap, long *)) = retval;
else if (zflag)
*(va_arg(ap, size_t *)) = retval;
else if (hflag)
*(va_arg(ap, short *)) = retval;
else if (cflag)
*(va_arg(ap, char *)) = retval;
else
*(va_arg(ap, int *)) = retval;
break;
case 'o':
base = 8;
goto handle_nosign;
case 'p':
base = 16;
sharpflag = (width == 0);
sign = 0;
num = (uintptr_t)va_arg(ap, void *);
goto number;
case 'q':
qflag = 1;
goto reswitch;
case 'r':
base = radix;
if (sign)
goto handle_sign;
goto handle_nosign;
case 's':
p = va_arg(ap, char *);
if (p == NULL)
p = "(null)";
if (!dot)
n = strlen (p);
else
for (n = 0; n < dwidth && p[n]; n++)
continue;
width -= n;
if (!ladjust && width > 0)
while (width--)
PCHAR(padc);
while (n--)
PCHAR(*p++);
if (ladjust && width > 0)
while (width--)
PCHAR(padc);
break;
case 't':
tflag = 1;
goto reswitch;
case 'u':
base = 10;
goto handle_nosign;
case 'X':
upper = 1;
case 'x':
base = 16;
goto handle_nosign;
case 'y':
base = 16;
sign = 1;
goto handle_sign;
case 'z':
zflag = 1;
goto reswitch;
handle_nosign:
sign = 0;
if (jflag)
num = va_arg(ap, uintmax_t);
else if (qflag)
num = va_arg(ap, u_quad_t);
else if (tflag)
num = va_arg(ap, ptrdiff_t);
else if (lflag)
num = va_arg(ap, u_long);
else if (zflag)
num = va_arg(ap, size_t);
else if (hflag)
num = (u_short)va_arg(ap, int);
else if (cflag)
num = (u_char)va_arg(ap, int);
else
num = va_arg(ap, u_int);
goto number;
handle_sign:
if (jflag)
num = va_arg(ap, intmax_t);
else if (qflag)
num = va_arg(ap, quad_t);
else if (tflag)
num = va_arg(ap, ptrdiff_t);
else if (lflag)
num = va_arg(ap, long);
else if (zflag)
num = va_arg(ap, ssize_t);
else if (hflag)
num = (short)va_arg(ap, int);
else if (cflag)
num = (char)va_arg(ap, int);
else
num = va_arg(ap, int);
number:
if (sign && (intmax_t)num < 0) {
neg = 1;
num = -(intmax_t)num;
}
p = ksprintn(nbuf, num, base, &n, upper);
tmp = 0;
if (sharpflag && num != 0) {
if (base == 8)
tmp++;
else if (base == 16)
tmp += 2;
}
if (neg)
tmp++;
if (!ladjust && padc == '0')
dwidth = width - tmp;
width -= tmp + imax(dwidth, n);
dwidth -= n;
if (!ladjust)
while (width-- > 0)
PCHAR(' ');
if (neg)
PCHAR('-');
if (sharpflag && num != 0) {
if (base == 8) {
PCHAR('0');
} else if (base == 16) {
PCHAR('0');
PCHAR('x');
}
}
while (dwidth-- > 0)
PCHAR('0');
while (*p)
PCHAR(*p--);
if (ladjust)
while (width-- > 0)
PCHAR(' ');
break;
default:
while (percent < fmt)
PCHAR(*percent++);
/*
* Since we ignore a formatting argument it is no
* longer safe to obey the remaining formatting
* arguments as the arguments will no longer match
* the format specs.
*/
stop = 1;
break;
}
}
#undef PCHAR
}
/*
* Put character in log buffer with a particular priority.
*/
static void
msglogchar(int c, int pri)
{
static int lastpri = -1;
static int dangling;
char nbuf[MAXNBUF];
char *p;
if (!msgbufmapped)
return;
if (c == '\0' || c == '\r')
return;
if (pri != -1 && pri != lastpri) {
if (dangling) {
msgbuf_addchar(msgbufp, '\n');
dangling = 0;
}
msgbuf_addchar(msgbufp, '<');
for (p = ksprintn(nbuf, (uintmax_t)pri, 10, NULL, 0); *p;)
msgbuf_addchar(msgbufp, *p--);
msgbuf_addchar(msgbufp, '>');
lastpri = pri;
}
msgbuf_addchar(msgbufp, c);
if (c == '\n') {
dangling = 0;
lastpri = -1;
} else {
dangling = 1;
}
}
static void
msglogstr(char *str, int pri, int filter_cr)
{
if (!msgbufmapped)
return;
msgbuf_addstr(msgbufp, pri, str, filter_cr);
}
void
msgbufinit(void *ptr, int size)
{
char *cp;
static struct msgbuf *oldp = NULL;
size -= sizeof(*msgbufp);
cp = (char *)ptr;
msgbufp = (struct msgbuf *)(cp + size);
msgbuf_reinit(msgbufp, cp, size);
if (msgbufmapped && oldp != msgbufp)
msgbuf_copy(oldp, msgbufp);
msgbufmapped = 1;
oldp = msgbufp;
}
static int unprivileged_read_msgbuf = 1;
SYSCTL_INT(_security_bsd, OID_AUTO, unprivileged_read_msgbuf,
CTLFLAG_RW, &unprivileged_read_msgbuf, 0,
"Unprivileged processes may read the kernel message buffer");
/* Sysctls for accessing/clearing the msgbuf */
static int
sysctl_kern_msgbuf(SYSCTL_HANDLER_ARGS)
{
char buf[128];
u_int seq;
int error, len;
if (!unprivileged_read_msgbuf) {
error = priv_check(req->td, PRIV_MSGBUF);
if (error)
return (error);
}
/* Read the whole buffer, one chunk at a time. */
mtx_lock(&msgbuf_lock);
msgbuf_peekbytes(msgbufp, NULL, 0, &seq);
for (;;) {
len = msgbuf_peekbytes(msgbufp, buf, sizeof(buf), &seq);
mtx_unlock(&msgbuf_lock);
if (len == 0)
return (SYSCTL_OUT(req, "", 1)); /* add nulterm */
error = sysctl_handle_opaque(oidp, buf, len, req);
if (error)
return (error);
mtx_lock(&msgbuf_lock);
}
}
SYSCTL_PROC(_kern, OID_AUTO, msgbuf,
CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
NULL, 0, sysctl_kern_msgbuf, "A", "Contents of kernel message buffer");
static int msgbuf_clearflag;
static int
sysctl_kern_msgbuf_clear(SYSCTL_HANDLER_ARGS)
{
int error;
error = sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2, req);
if (!error && req->newptr) {
mtx_lock(&msgbuf_lock);
msgbuf_clear(msgbufp);
mtx_unlock(&msgbuf_lock);
msgbuf_clearflag = 0;
}
return (error);
}
SYSCTL_PROC(_kern, OID_AUTO, msgbuf_clear,
CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE | CTLFLAG_MPSAFE,
&msgbuf_clearflag, 0, sysctl_kern_msgbuf_clear, "I",
"Clear kernel message buffer");
#ifdef DDB
DB_SHOW_COMMAND(msgbuf, db_show_msgbuf)
{
int i, j;
if (!msgbufmapped) {
db_printf("msgbuf not mapped yet\n");
return;
}
db_printf("msgbufp = %p\n", msgbufp);
db_printf("magic = %x, size = %d, r= %u, w = %u, ptr = %p, cksum= %u\n",
msgbufp->msg_magic, msgbufp->msg_size, msgbufp->msg_rseq,
msgbufp->msg_wseq, msgbufp->msg_ptr, msgbufp->msg_cksum);
for (i = 0; i < msgbufp->msg_size && !db_pager_quit; i++) {
j = MSGBUF_SEQ_TO_POS(msgbufp, i + msgbufp->msg_rseq);
db_printf("%c", msgbufp->msg_ptr[j]);
}
db_printf("\n");
}
#endif /* DDB */
void
hexdump(const void *ptr, int length, const char *hdr, int flags)
{
int i, j, k;
int cols;
const unsigned char *cp;
char delim;
if ((flags & HD_DELIM_MASK) != 0)
delim = (flags & HD_DELIM_MASK) >> 8;
else
delim = ' ';
if ((flags & HD_COLUMN_MASK) != 0)
cols = flags & HD_COLUMN_MASK;
else
cols = 16;
cp = ptr;
for (i = 0; i < length; i+= cols) {
if (hdr != NULL)
printf("%s", hdr);
if ((flags & HD_OMIT_COUNT) == 0)
printf("%04x ", i);
if ((flags & HD_OMIT_HEX) == 0) {
for (j = 0; j < cols; j++) {
k = i + j;
if (k < length)
printf("%c%02x", delim, cp[k]);
else
printf(" ");
}
}
if ((flags & HD_OMIT_CHARS) == 0) {
printf(" |");
for (j = 0; j < cols; j++) {
k = i + j;
if (k >= length)
printf(" ");
else if (cp[k] >= ' ' && cp[k] <= '~')
printf("%c", cp[k]);
else
printf(".");
}
printf("|");
}
printf("\n");
}
}