Initial import from FreeBSD RELENG_4:
[dragonfly.git] / sys / kern / subr_prf.c
CommitLineData
984263bc
MD
1/*-
2 * Copyright (c) 1986, 1988, 1991, 1993
3 * The Regents of the University of California. All rights reserved.
4 * (c) UNIX System Laboratories, Inc.
5 * All or some portions of this file are derived from material licensed
6 * to the University of California by American Telephone and Telegraph
7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8 * the permission of UNIX System Laboratories, Inc.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by the University of
21 * California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 * may be used to endorse or promote products derived from this software
24 * without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * SUCH DAMAGE.
37 *
38 * @(#)subr_prf.c 8.3 (Berkeley) 1/21/94
39 * $FreeBSD: src/sys/kern/subr_prf.c,v 1.61.2.5 2002/08/31 18:22:08 dwmalone Exp $
40 */
41
42#include <sys/param.h>
43#include <sys/systm.h>
44#include <sys/kernel.h>
45#include <sys/msgbuf.h>
46#include <sys/malloc.h>
47#include <sys/proc.h>
48#include <sys/tty.h>
49#include <sys/tprintf.h>
50#include <sys/syslog.h>
51#include <sys/cons.h>
52#include <sys/uio.h>
53#include <sys/sysctl.h>
54
55/*
56 * Note that stdarg.h and the ANSI style va_start macro is used for both
57 * ANSI and traditional C compilers.
58 */
59#include <machine/stdarg.h>
60
61#define TOCONS 0x01
62#define TOTTY 0x02
63#define TOLOG 0x04
64
65/* Max number conversion buffer length: a u_quad_t in base 2, plus NUL byte. */
66#define MAXNBUF (sizeof(quad_t) * NBBY + 1)
67
68struct putchar_arg {
69 int flags;
70 int pri;
71 struct tty *tty;
72};
73
74struct snprintf_arg {
75 char *str;
76 size_t remain;
77};
78
79extern int log_open;
80
81struct tty *constty; /* pointer to console "window" tty */
82
83static void (*v_putc)(int) = cnputc; /* routine to putc on virtual console */
84static void msglogchar(int c, int pri);
85static void msgaddchar(int c, void *dummy);
86static void putchar __P((int ch, void *arg));
87static char *ksprintn __P((char *nbuf, u_long num, int base, int *len));
88static char *ksprintqn __P((char *nbuf, u_quad_t num, int base, int *len));
89static void snprintf_func __P((int ch, void *arg));
90
91static int consintr = 1; /* Ok to handle console interrupts? */
92static int msgbufmapped; /* Set when safe to use msgbuf */
93int msgbuftrigger;
94
95static int log_console_output = 1;
96TUNABLE_INT("kern.log_console_output", &log_console_output);
97SYSCTL_INT(_kern, OID_AUTO, log_console_output, CTLFLAG_RW,
98 &log_console_output, 0, "");
99
100/*
101 * Warn that a system table is full.
102 */
103void
104tablefull(const char *tab)
105{
106
107 log(LOG_ERR, "%s: table is full\n", tab);
108}
109
110/*
111 * Uprintf prints to the controlling terminal for the current process.
112 * It may block if the tty queue is overfull. No message is printed if
113 * the queue does not clear in a reasonable time.
114 */
115int
116uprintf(const char *fmt, ...)
117{
118 struct proc *p = curproc;
119 va_list ap;
120 struct putchar_arg pca;
121 int retval = 0;
122
123 if (p && p->p_flag & P_CONTROLT &&
124 p->p_session->s_ttyvp) {
125 va_start(ap, fmt);
126 pca.tty = p->p_session->s_ttyp;
127 pca.flags = TOTTY;
128 retval = kvprintf(fmt, putchar, &pca, 10, ap);
129 va_end(ap);
130 }
131 return retval;
132}
133
134tpr_t
135tprintf_open(p)
136 register struct proc *p;
137{
138
139 if (p->p_flag & P_CONTROLT && p->p_session->s_ttyvp) {
140 SESSHOLD(p->p_session);
141 return ((tpr_t) p->p_session);
142 }
143 return ((tpr_t) NULL);
144}
145
146void
147tprintf_close(sess)
148 tpr_t sess;
149{
150
151 if (sess)
152 SESSRELE((struct session *) sess);
153}
154
155/*
156 * tprintf prints on the controlling terminal associated
157 * with the given session.
158 */
159int
160tprintf(tpr_t tpr, const char *fmt, ...)
161{
162 register struct session *sess = (struct session *)tpr;
163 struct tty *tp = NULL;
164 int flags = TOLOG;
165 va_list ap;
166 struct putchar_arg pca;
167 int retval;
168
169 if (sess && sess->s_ttyvp && ttycheckoutq(sess->s_ttyp, 0)) {
170 flags |= TOTTY;
171 tp = sess->s_ttyp;
172 }
173 va_start(ap, fmt);
174 pca.tty = tp;
175 pca.flags = flags;
176 pca.pri = LOG_INFO;
177 retval = kvprintf(fmt, putchar, &pca, 10, ap);
178 va_end(ap);
179 msgbuftrigger = 1;
180 return retval;
181}
182
183/*
184 * Ttyprintf displays a message on a tty; it should be used only by
185 * the tty driver, or anything that knows the underlying tty will not
186 * be revoke(2)'d away. Other callers should use tprintf.
187 */
188int
189ttyprintf(struct tty *tp, const char *fmt, ...)
190{
191 va_list ap;
192 struct putchar_arg pca;
193 int retval;
194
195 va_start(ap, fmt);
196 pca.tty = tp;
197 pca.flags = TOTTY;
198 retval = kvprintf(fmt, putchar, &pca, 10, ap);
199 va_end(ap);
200 return retval;
201}
202
203/*
204 * Log writes to the log buffer, and guarantees not to sleep (so can be
205 * called by interrupt routines). If there is no process reading the
206 * log yet, it writes to the console also.
207 */
208int
209log(int level, const char *fmt, ...)
210{
211 va_list ap;
212 int retval;
213 struct putchar_arg pca;
214
215 pca.tty = NULL;
216 pca.pri = level;
217 pca.flags = log_open ? TOLOG : TOCONS;
218
219 va_start(ap, fmt);
220 retval = kvprintf(fmt, putchar, &pca, 10, ap);
221 va_end(ap);
222
223 msgbuftrigger = 1;
224 return (retval);
225}
226
227int
228addlog(const char *fmt, ...)
229{
230 va_list ap;
231 int retval;
232 struct putchar_arg pca;
233
234 pca.tty = NULL;
235 pca.pri = -1;
236 pca.flags = log_open ? TOLOG : TOCONS;
237
238 va_start(ap, fmt);
239 retval = kvprintf(fmt, putchar, &pca, 10, ap);
240 va_end(ap);
241
242 msgbuftrigger = 1;
243 return (retval);
244}
245
246#define CONSCHUNK 128
247
248void
249log_console(struct uio *uio)
250{
251 int c, i, error, iovlen, nl;
252 struct uio muio;
253 struct iovec *miov = NULL;
254 char *consbuffer;
255 int pri;
256
257 if (!log_console_output)
258 return;
259
260 pri = LOG_INFO | LOG_CONSOLE;
261 muio = *uio;
262 iovlen = uio->uio_iovcnt * sizeof (struct iovec);
263 MALLOC(miov, struct iovec *, iovlen, M_TEMP, M_WAITOK);
264 MALLOC(consbuffer, char *, CONSCHUNK, M_TEMP, M_WAITOK);
265 bcopy((caddr_t)muio.uio_iov, (caddr_t)miov, iovlen);
266 muio.uio_iov = miov;
267 uio = &muio;
268
269 nl = 0;
270 while (uio->uio_resid > 0) {
271 c = imin(uio->uio_resid, CONSCHUNK);
272 error = uiomove(consbuffer, c, uio);
273 if (error != 0)
274 return;
275 for (i = 0; i < c; i++) {
276 msglogchar(consbuffer[i], pri);
277 if (consbuffer[i] == '\n')
278 nl = 1;
279 else
280 nl = 0;
281 }
282 }
283 if (!nl)
284 msglogchar('\n', pri);
285 msgbuftrigger = 1;
286 FREE(miov, M_TEMP);
287 FREE(consbuffer, M_TEMP);
288 return;
289}
290
291int
292printf(const char *fmt, ...)
293{
294 va_list ap;
295 int savintr;
296 struct putchar_arg pca;
297 int retval;
298
299 savintr = consintr; /* disable interrupts */
300 consintr = 0;
301 va_start(ap, fmt);
302 pca.tty = NULL;
303 pca.flags = TOCONS | TOLOG;
304 pca.pri = -1;
305 retval = kvprintf(fmt, putchar, &pca, 10, ap);
306 va_end(ap);
307 if (!panicstr)
308 msgbuftrigger = 1;
309 consintr = savintr; /* reenable interrupts */
310 return retval;
311}
312
313int
314vprintf(const char *fmt, va_list ap)
315{
316 int savintr;
317 struct putchar_arg pca;
318 int retval;
319
320 savintr = consintr; /* disable interrupts */
321 consintr = 0;
322 pca.tty = NULL;
323 pca.flags = TOCONS | TOLOG;
324 pca.pri = -1;
325 retval = kvprintf(fmt, putchar, &pca, 10, ap);
326 if (!panicstr)
327 msgbuftrigger = 1;
328 consintr = savintr; /* reenable interrupts */
329 return retval;
330}
331
332/*
333 * Print a character on console or users terminal. If destination is
334 * the console then the last bunch of characters are saved in msgbuf for
335 * inspection later.
336 */
337static void
338putchar(int c, void *arg)
339{
340 struct putchar_arg *ap = (struct putchar_arg*) arg;
341 int flags = ap->flags;
342 struct tty *tp = ap->tty;
343 if (panicstr)
344 constty = NULL;
345 if ((flags & TOCONS) && tp == NULL && constty) {
346 tp = constty;
347 flags |= TOTTY;
348 }
349 if ((flags & TOTTY) && tp && tputchar(c, tp) < 0 &&
350 (flags & TOCONS) && tp == constty)
351 constty = NULL;
352 if ((flags & TOLOG))
353 msglogchar(c, ap->pri);
354 if ((flags & TOCONS) && constty == NULL && c != '\0')
355 (*v_putc)(c);
356}
357
358/*
359 * Scaled down version of sprintf(3).
360 */
361int
362sprintf(char *buf, const char *cfmt, ...)
363{
364 int retval;
365 va_list ap;
366
367 va_start(ap, cfmt);
368 retval = kvprintf(cfmt, NULL, (void *)buf, 10, ap);
369 buf[retval] = '\0';
370 va_end(ap);
371 return retval;
372}
373
374/*
375 * Scaled down version of vsprintf(3).
376 */
377int
378vsprintf(char *buf, const char *cfmt, va_list ap)
379{
380 int retval;
381
382 retval = kvprintf(cfmt, NULL, (void *)buf, 10, ap);
383 buf[retval] = '\0';
384 return retval;
385}
386
387/*
388 * Scaled down version of snprintf(3).
389 */
390int
391snprintf(char *str, size_t size, const char *format, ...)
392{
393 int retval;
394 va_list ap;
395
396 va_start(ap, format);
397 retval = vsnprintf(str, size, format, ap);
398 va_end(ap);
399 return(retval);
400}
401
402/*
403 * Scaled down version of vsnprintf(3).
404 */
405int
406vsnprintf(char *str, size_t size, const char *format, va_list ap)
407{
408 struct snprintf_arg info;
409 int retval;
410
411 info.str = str;
412 info.remain = size;
413 retval = kvprintf(format, snprintf_func, &info, 10, ap);
414 if (info.remain >= 1)
415 *info.str++ = '\0';
416 return retval;
417}
418
419static void
420snprintf_func(int ch, void *arg)
421{
422 struct snprintf_arg *const info = arg;
423
424 if (info->remain >= 2) {
425 *info->str++ = ch;
426 info->remain--;
427 }
428}
429
430/*
431 * Put a NUL-terminated ASCII number (base <= 36) in a buffer in reverse
432 * order; return an optional length and a pointer to the last character
433 * written in the buffer (i.e., the first character of the string).
434 * The buffer pointed to by `nbuf' must have length >= MAXNBUF.
435 */
436static char *
437ksprintn(nbuf, ul, base, lenp)
438 char *nbuf;
439 u_long ul;
440 int base, *lenp;
441{
442 char *p;
443
444 p = nbuf;
445 *p = '\0';
446 do {
447 *++p = hex2ascii(ul % base);
448 } while (ul /= base);
449 if (lenp)
450 *lenp = p - nbuf;
451 return (p);
452}
453/* ksprintn, but for a quad_t. */
454static char *
455ksprintqn(nbuf, uq, base, lenp)
456 char *nbuf;
457 u_quad_t uq;
458 int base, *lenp;
459{
460 char *p;
461
462 p = nbuf;
463 *p = '\0';
464 do {
465 *++p = hex2ascii(uq % base);
466 } while (uq /= base);
467 if (lenp)
468 *lenp = p - nbuf;
469 return (p);
470}
471
472/*
473 * Scaled down version of printf(3).
474 *
475 * Two additional formats:
476 *
477 * The format %b is supported to decode error registers.
478 * Its usage is:
479 *
480 * printf("reg=%b\n", regval, "<base><arg>*");
481 *
482 * where <base> is the output base expressed as a control character, e.g.
483 * \10 gives octal; \20 gives hex. Each arg is a sequence of characters,
484 * the first of which gives the bit number to be inspected (origin 1), and
485 * the next characters (up to a control character, i.e. a character <= 32),
486 * give the name of the register. Thus:
487 *
488 * kvprintf("reg=%b\n", 3, "\10\2BITTWO\1BITONE\n");
489 *
490 * would produce output:
491 *
492 * reg=3<BITTWO,BITONE>
493 *
494 * XXX: %D -- Hexdump, takes pointer and separator string:
495 * ("%6D", ptr, ":") -> XX:XX:XX:XX:XX:XX
496 * ("%*D", len, ptr, " " -> XX XX XX XX ...
497 */
498int
499kvprintf(char const *fmt, void (*func)(int, void*), void *arg, int radix, va_list ap)
500{
501#define PCHAR(c) {int cc=(c); if (func) (*func)(cc,arg); else *d++ = cc; retval++; }
502 char nbuf[MAXNBUF];
503 char *p, *q, *d;
504 u_char *up;
505 int ch, n;
506 u_long ul;
507 u_quad_t uq;
508 int base, lflag, qflag, tmp, width, ladjust, sharpflag, neg, sign, dot;
509 int dwidth;
510 char padc;
511 int retval = 0;
512
513 ul = 0;
514 uq = 0;
515 if (!func)
516 d = (char *) arg;
517 else
518 d = NULL;
519
520 if (fmt == NULL)
521 fmt = "(fmt null)\n";
522
523 if (radix < 2 || radix > 36)
524 radix = 10;
525
526 for (;;) {
527 padc = ' ';
528 width = 0;
529 while ((ch = (u_char)*fmt++) != '%') {
530 if (ch == '\0')
531 return retval;
532 PCHAR(ch);
533 }
534 qflag = 0; lflag = 0; ladjust = 0; sharpflag = 0; neg = 0;
535 sign = 0; dot = 0; dwidth = 0;
536reswitch: switch (ch = (u_char)*fmt++) {
537 case '.':
538 dot = 1;
539 goto reswitch;
540 case '#':
541 sharpflag = 1;
542 goto reswitch;
543 case '+':
544 sign = 1;
545 goto reswitch;
546 case '-':
547 ladjust = 1;
548 goto reswitch;
549 case '%':
550 PCHAR(ch);
551 break;
552 case '*':
553 if (!dot) {
554 width = va_arg(ap, int);
555 if (width < 0) {
556 ladjust = !ladjust;
557 width = -width;
558 }
559 } else {
560 dwidth = va_arg(ap, int);
561 }
562 goto reswitch;
563 case '0':
564 if (!dot) {
565 padc = '0';
566 goto reswitch;
567 }
568 case '1': case '2': case '3': case '4':
569 case '5': case '6': case '7': case '8': case '9':
570 for (n = 0;; ++fmt) {
571 n = n * 10 + ch - '0';
572 ch = *fmt;
573 if (ch < '0' || ch > '9')
574 break;
575 }
576 if (dot)
577 dwidth = n;
578 else
579 width = n;
580 goto reswitch;
581 case 'b':
582 ul = va_arg(ap, int);
583 p = va_arg(ap, char *);
584 for (q = ksprintn(nbuf, ul, *p++, NULL); *q;)
585 PCHAR(*q--);
586
587 if (!ul)
588 break;
589
590 for (tmp = 0; *p;) {
591 n = *p++;
592 if (ul & (1 << (n - 1))) {
593 PCHAR(tmp ? ',' : '<');
594 for (; (n = *p) > ' '; ++p)
595 PCHAR(n);
596 tmp = 1;
597 } else
598 for (; *p > ' '; ++p)
599 continue;
600 }
601 if (tmp)
602 PCHAR('>');
603 break;
604 case 'c':
605 PCHAR(va_arg(ap, int));
606 break;
607 case 'D':
608 up = va_arg(ap, u_char *);
609 p = va_arg(ap, char *);
610 if (!width)
611 width = 16;
612 while(width--) {
613 PCHAR(hex2ascii(*up >> 4));
614 PCHAR(hex2ascii(*up & 0x0f));
615 up++;
616 if (width)
617 for (q=p;*q;q++)
618 PCHAR(*q);
619 }
620 break;
621 case 'd':
622 if (qflag)
623 uq = va_arg(ap, quad_t);
624 else if (lflag)
625 ul = va_arg(ap, long);
626 else
627 ul = va_arg(ap, int);
628 sign = 1;
629 base = 10;
630 goto number;
631 case 'l':
632 if (lflag) {
633 lflag = 0;
634 qflag = 1;
635 } else
636 lflag = 1;
637 goto reswitch;
638 case 'o':
639 if (qflag)
640 uq = va_arg(ap, u_quad_t);
641 else if (lflag)
642 ul = va_arg(ap, u_long);
643 else
644 ul = va_arg(ap, u_int);
645 base = 8;
646 goto nosign;
647 case 'p':
648 ul = (uintptr_t)va_arg(ap, void *);
649 base = 16;
650 sharpflag = (width == 0);
651 goto nosign;
652 case 'q':
653 qflag = 1;
654 goto reswitch;
655 case 'n':
656 case 'r':
657 if (qflag)
658 uq = va_arg(ap, u_quad_t);
659 else if (lflag)
660 ul = va_arg(ap, u_long);
661 else
662 ul = sign ?
663 (u_long)va_arg(ap, int) : va_arg(ap, u_int);
664 base = radix;
665 goto number;
666 case 's':
667 p = va_arg(ap, char *);
668 if (p == NULL)
669 p = "(null)";
670 if (!dot)
671 n = strlen (p);
672 else
673 for (n = 0; n < dwidth && p[n]; n++)
674 continue;
675
676 width -= n;
677
678 if (!ladjust && width > 0)
679 while (width--)
680 PCHAR(padc);
681 while (n--)
682 PCHAR(*p++);
683 if (ladjust && width > 0)
684 while (width--)
685 PCHAR(padc);
686 break;
687 case 'u':
688 if (qflag)
689 uq = va_arg(ap, u_quad_t);
690 else if (lflag)
691 ul = va_arg(ap, u_long);
692 else
693 ul = va_arg(ap, u_int);
694 base = 10;
695 goto nosign;
696 case 'x':
697 case 'X':
698 if (qflag)
699 uq = va_arg(ap, u_quad_t);
700 else if (lflag)
701 ul = va_arg(ap, u_long);
702 else
703 ul = va_arg(ap, u_int);
704 base = 16;
705 goto nosign;
706 case 'z':
707 if (qflag)
708 uq = va_arg(ap, u_quad_t);
709 else if (lflag)
710 ul = va_arg(ap, u_long);
711 else
712 ul = sign ?
713 (u_long)va_arg(ap, int) : va_arg(ap, u_int);
714 base = 16;
715 goto number;
716nosign: sign = 0;
717number:
718 if (qflag) {
719 if (sign && (quad_t)uq < 0) {
720 neg = 1;
721 uq = -(quad_t)uq;
722 }
723 p = ksprintqn(nbuf, uq, base, &tmp);
724 } else {
725 if (sign && (long)ul < 0) {
726 neg = 1;
727 ul = -(long)ul;
728 }
729 p = ksprintn(nbuf, ul, base, &tmp);
730 }
731 if (sharpflag && (qflag ? uq != 0 : ul != 0)) {
732 if (base == 8)
733 tmp++;
734 else if (base == 16)
735 tmp += 2;
736 }
737 if (neg)
738 tmp++;
739
740 if (!ladjust && width && (width -= tmp) > 0)
741 while (width--)
742 PCHAR(padc);
743 if (neg)
744 PCHAR('-');
745 if (sharpflag && (qflag ? uq != 0 : ul != 0)) {
746 if (base == 8) {
747 PCHAR('0');
748 } else if (base == 16) {
749 PCHAR('0');
750 PCHAR('x');
751 }
752 }
753
754 while (*p)
755 PCHAR(*p--);
756
757 if (ladjust && width && (width -= tmp) > 0)
758 while (width--)
759 PCHAR(padc);
760
761 break;
762 default:
763 PCHAR('%');
764 if (lflag)
765 PCHAR('l');
766 PCHAR(ch);
767 break;
768 }
769 }
770#undef PCHAR
771}
772
773/*
774 * Put character in log buffer with a particular priority.
775 */
776static void
777msglogchar(int c, int pri)
778{
779 static int lastpri = -1;
780 static int dangling;
781 char nbuf[MAXNBUF];
782 char *p;
783
784 if (!msgbufmapped)
785 return;
786 if (c == '\0' || c == '\r')
787 return;
788 if (pri != -1 && pri != lastpri) {
789 if (dangling) {
790 msgaddchar('\n', NULL);
791 dangling = 0;
792 }
793 msgaddchar('<', NULL);
794 for (p = ksprintn(nbuf, (u_long)pri, 10, NULL); *p;)
795 msgaddchar(*p--, NULL);
796 msgaddchar('>', NULL);
797 lastpri = pri;
798 }
799 msgaddchar(c, NULL);
800 if (c == '\n') {
801 dangling = 0;
802 lastpri = -1;
803 } else {
804 dangling = 1;
805 }
806}
807
808/*
809 * Put char in log buffer
810 */
811static void
812msgaddchar(int c, void *dummy)
813{
814 struct msgbuf *mbp;
815
816 if (!msgbufmapped)
817 return;
818 mbp = msgbufp;
819 mbp->msg_ptr[mbp->msg_bufx++] = c;
820 if (mbp->msg_bufx >= mbp->msg_size)
821 mbp->msg_bufx = 0;
822 /* If the buffer is full, keep the most recent data. */
823 if (mbp->msg_bufr == mbp->msg_bufx) {
824 if (++mbp->msg_bufr >= mbp->msg_size)
825 mbp->msg_bufr = 0;
826 }
827}
828
829static void
830msgbufcopy(struct msgbuf *oldp)
831{
832 int pos;
833
834 pos = oldp->msg_bufr;
835 while (pos != oldp->msg_bufx) {
836 msglogchar(oldp->msg_ptr[pos], -1);
837 if (++pos >= oldp->msg_size)
838 pos = 0;
839 }
840}
841
842void
843msgbufinit(void *ptr, size_t size)
844{
845 char *cp;
846 static struct msgbuf *oldp = NULL;
847
848 size -= sizeof(*msgbufp);
849 cp = (char *)ptr;
850 msgbufp = (struct msgbuf *) (cp + size);
851 if (msgbufp->msg_magic != MSG_MAGIC || msgbufp->msg_size != size ||
852 msgbufp->msg_bufx >= size || msgbufp->msg_bufr >= size) {
853 bzero(cp, size);
854 bzero(msgbufp, sizeof(*msgbufp));
855 msgbufp->msg_magic = MSG_MAGIC;
856 msgbufp->msg_size = (char *)msgbufp - cp;
857 }
858 msgbufp->msg_ptr = cp;
859 if (msgbufmapped && oldp != msgbufp)
860 msgbufcopy(oldp);
861 msgbufmapped = 1;
862 oldp = msgbufp;
863}
864
865/* Sysctls for accessing/clearing the msgbuf */
866static int
867sysctl_kern_msgbuf(SYSCTL_HANDLER_ARGS)
868{
869 int error;
870
871 /*
872 * Unwind the buffer, so that it's linear (possibly starting with
873 * some initial nulls).
874 */
875 error = sysctl_handle_opaque(oidp, msgbufp->msg_ptr + msgbufp->msg_bufx,
876 msgbufp->msg_size - msgbufp->msg_bufx, req);
877 if (error)
878 return (error);
879 if (msgbufp->msg_bufx > 0) {
880 error = sysctl_handle_opaque(oidp, msgbufp->msg_ptr,
881 msgbufp->msg_bufx, req);
882 }
883 return (error);
884}
885
886SYSCTL_PROC(_kern, OID_AUTO, msgbuf, CTLTYPE_STRING | CTLFLAG_RD,
887 0, 0, sysctl_kern_msgbuf, "A", "Contents of kernel message buffer");
888
889static int msgbuf_clear;
890
891static int
892sysctl_kern_msgbuf_clear(SYSCTL_HANDLER_ARGS)
893{
894 int error;
895 error = sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2, req);
896 if (!error && req->newptr) {
897 /* Clear the buffer and reset write pointer */
898 bzero(msgbufp->msg_ptr, msgbufp->msg_size);
899 msgbufp->msg_bufr = msgbufp->msg_bufx = 0;
900 msgbuf_clear = 0;
901 }
902 return (error);
903}
904
905SYSCTL_PROC(_kern, OID_AUTO, msgbuf_clear,
906 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE, &msgbuf_clear, 0,
907 sysctl_kern_msgbuf_clear, "I", "Clear kernel message buffer");
908
909#include "opt_ddb.h"
910#ifdef DDB
911#include <ddb/ddb.h>
912
913DB_SHOW_COMMAND(msgbuf, db_show_msgbuf)
914{
915 int i, j;
916
917 if (!msgbufmapped) {
918 db_printf("msgbuf not mapped yet\n");
919 return;
920 }
921 db_printf("msgbufp = %p\n", msgbufp);
922 db_printf("magic = %x, size = %d, r= %d, w = %d, ptr = %p\n",
923 msgbufp->msg_magic, msgbufp->msg_size, msgbufp->msg_bufr,
924 msgbufp->msg_bufx, msgbufp->msg_ptr);
925 for (i = 0; i < msgbufp->msg_size; i++) {
926 j = (i + msgbufp->msg_bufr) % msgbufp->msg_size;
927 db_printf("%c", msgbufp->msg_ptr[j]);
928 }
929 db_printf("\n");
930}
931
932#endif /* DDB */