xref: /freebsd/sys/kern/subr_prf.c (revision acd3428b7d3e94cef0e1881c868cb4b131d4ff41)
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  * 4. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, 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  *	@(#)subr_prf.c	8.3 (Berkeley) 1/21/94
35  */
36 
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
39 
40 #include "opt_ddb.h"
41 
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/lock.h>
45 #include <sys/kdb.h>
46 #include <sys/mutex.h>
47 #include <sys/sx.h>
48 #include <sys/kernel.h>
49 #include <sys/msgbuf.h>
50 #include <sys/malloc.h>
51 #include <sys/priv.h>
52 #include <sys/proc.h>
53 #include <sys/stddef.h>
54 #include <sys/sysctl.h>
55 #include <sys/tty.h>
56 #include <sys/syslog.h>
57 #include <sys/cons.h>
58 #include <sys/uio.h>
59 #include <sys/ctype.h>
60 
61 #ifdef DDB
62 #include <ddb/ddb.h>
63 #endif
64 
65 /*
66  * Note that stdarg.h and the ANSI style va_start macro is used for both
67  * ANSI and traditional C compilers.
68  */
69 #include <machine/stdarg.h>
70 
71 #define TOCONS	0x01
72 #define TOTTY	0x02
73 #define TOLOG	0x04
74 
75 /* Max number conversion buffer length: a u_quad_t in base 2, plus NUL byte. */
76 #define MAXNBUF	(sizeof(intmax_t) * NBBY + 1)
77 
78 struct putchar_arg {
79 	int	flags;
80 	int	pri;
81 	struct	tty *tty;
82 	char	*p_bufr;
83 	size_t	n_bufr;
84 	char	*p_next;
85 	size_t	remain;
86 };
87 
88 struct snprintf_arg {
89 	char	*str;
90 	size_t	remain;
91 };
92 
93 extern	int log_open;
94 
95 static void  msglogchar(int c, int pri);
96 static void  putchar(int ch, void *arg);
97 static char *ksprintn(char *nbuf, uintmax_t num, int base, int *len, int upper);
98 static void  snprintf_func(int ch, void *arg);
99 
100 static int msgbufmapped;		/* Set when safe to use msgbuf */
101 int msgbuftrigger;
102 
103 static int      log_console_output = 1;
104 TUNABLE_INT("kern.log_console_output", &log_console_output);
105 SYSCTL_INT(_kern, OID_AUTO, log_console_output, CTLFLAG_RW,
106     &log_console_output, 0, "Duplicate console output to the syslog.");
107 
108 static int	always_console_output = 0;
109 TUNABLE_INT("kern.always_console_output", &always_console_output);
110 SYSCTL_INT(_kern, OID_AUTO, always_console_output, CTLFLAG_RW,
111     &always_console_output, 0, "Always output to console despite TIOCCONS.");
112 
113 /*
114  * Warn that a system table is full.
115  */
116 void
117 tablefull(const char *tab)
118 {
119 
120 	log(LOG_ERR, "%s: table is full\n", tab);
121 }
122 
123 /*
124  * Uprintf prints to the controlling terminal for the current process.
125  */
126 int
127 uprintf(const char *fmt, ...)
128 {
129 	struct thread *td = curthread;
130 	struct proc *p = td->td_proc;
131 	va_list ap;
132 	struct putchar_arg pca;
133 	int retval;
134 
135 	if (td == NULL || td == PCPU_GET(idlethread))
136 		return (0);
137 
138 	mtx_lock(&Giant);
139 	p = td->td_proc;
140 	PROC_LOCK(p);
141 	if ((p->p_flag & P_CONTROLT) == 0) {
142 		PROC_UNLOCK(p);
143 		retval = 0;
144 		goto out;
145 	}
146 	SESS_LOCK(p->p_session);
147 	pca.tty = p->p_session->s_ttyp;
148 	SESS_UNLOCK(p->p_session);
149 	PROC_UNLOCK(p);
150 	if (pca.tty == NULL) {
151 		retval = 0;
152 		goto out;
153 	}
154 	pca.flags = TOTTY;
155 	va_start(ap, fmt);
156 	retval = kvprintf(fmt, putchar, &pca, 10, ap);
157 	va_end(ap);
158 out:
159 	mtx_unlock(&Giant);
160 	return (retval);
161 }
162 
163 /*
164  * tprintf prints on the controlling terminal associated with the given
165  * session, possibly to the log as well.
166  */
167 void
168 tprintf(struct proc *p, int pri, const char *fmt, ...)
169 {
170 	struct tty *tp = NULL;
171 	int flags = 0;
172 	va_list ap;
173 	struct putchar_arg pca;
174 	struct session *sess = NULL;
175 
176 	mtx_lock(&Giant);
177 	if (pri != -1)
178 		flags |= TOLOG;
179 	if (p != NULL) {
180 		PROC_LOCK(p);
181 		if (p->p_flag & P_CONTROLT && p->p_session->s_ttyvp) {
182 			sess = p->p_session;
183 			SESS_LOCK(sess);
184 			PROC_UNLOCK(p);
185 			SESSHOLD(sess);
186 			tp = sess->s_ttyp;
187 			SESS_UNLOCK(sess);
188 			if (ttycheckoutq(tp, 0))
189 				flags |= TOTTY;
190 			else
191 				tp = NULL;
192 		} else
193 			PROC_UNLOCK(p);
194 	}
195 	pca.pri = pri;
196 	pca.tty = tp;
197 	pca.flags = flags;
198 	va_start(ap, fmt);
199 	kvprintf(fmt, putchar, &pca, 10, ap);
200 	va_end(ap);
201 	if (sess != NULL)
202 		SESSRELE(sess);
203 	msgbuftrigger = 1;
204 	mtx_unlock(&Giant);
205 }
206 
207 /*
208  * Ttyprintf displays a message on a tty; it should be used only by
209  * the tty driver, or anything that knows the underlying tty will not
210  * be revoke(2)'d away.  Other callers should use tprintf.
211  */
212 int
213 ttyprintf(struct tty *tp, const char *fmt, ...)
214 {
215 	va_list ap;
216 	struct putchar_arg pca;
217 	int retval;
218 
219 	va_start(ap, fmt);
220 	pca.tty = tp;
221 	pca.flags = TOTTY;
222 	retval = kvprintf(fmt, putchar, &pca, 10, ap);
223 	va_end(ap);
224 	return (retval);
225 }
226 
227 /*
228  * Log writes to the log buffer, and guarantees not to sleep (so can be
229  * called by interrupt routines).  If there is no process reading the
230  * log yet, it writes to the console also.
231  */
232 void
233 log(int level, const char *fmt, ...)
234 {
235 	va_list ap;
236 	struct putchar_arg pca;
237 
238 	pca.tty = NULL;
239 	pca.pri = level;
240 	pca.flags = log_open ? TOLOG : TOCONS;
241 	pca.p_bufr = NULL;
242 
243 	va_start(ap, fmt);
244 	kvprintf(fmt, putchar, &pca, 10, ap);
245 	va_end(ap);
246 
247 	msgbuftrigger = 1;
248 }
249 
250 #define CONSCHUNK 128
251 
252 void
253 log_console(struct uio *uio)
254 {
255 	int c, i, error, nl;
256 	char *consbuffer;
257 	int pri;
258 
259 	if (!log_console_output)
260 		return;
261 
262 	pri = LOG_INFO | LOG_CONSOLE;
263 	uio = cloneuio(uio);
264 	consbuffer = malloc(CONSCHUNK, M_TEMP, M_WAITOK);
265 
266 	nl = 0;
267 	while (uio->uio_resid > 0) {
268 		c = imin(uio->uio_resid, CONSCHUNK);
269 		error = uiomove(consbuffer, c, uio);
270 		if (error != 0)
271 			break;
272 		for (i = 0; i < c; i++) {
273 			msglogchar(consbuffer[i], pri);
274 			if (consbuffer[i] == '\n')
275 				nl = 1;
276 			else
277 				nl = 0;
278 		}
279 	}
280 	if (!nl)
281 		msglogchar('\n', pri);
282 	msgbuftrigger = 1;
283 	free(uio, M_IOV);
284 	free(consbuffer, M_TEMP);
285 	return;
286 }
287 
288 int
289 printf(const char *fmt, ...)
290 {
291 	va_list ap;
292 	struct putchar_arg pca;
293 	int retval;
294 
295 	critical_enter();
296 
297 	va_start(ap, fmt);
298 	pca.tty = NULL;
299 	pca.flags = TOCONS | TOLOG;
300 	pca.pri = -1;
301 	pca.p_bufr = (char *) PCPU_PTR(cons_bufr);
302 	pca.p_next = pca.p_bufr;
303 	pca.n_bufr = PCPU_CONS_BUFR;
304 	pca.remain = PCPU_CONS_BUFR;
305 	*pca.p_next = '\0';
306 
307 	retval = kvprintf(fmt, putchar, &pca, 10, ap);
308 	va_end(ap);
309 
310 	/* Write any buffered console output: */
311 	if (*pca.p_bufr != '\0')
312 		cnputs(pca.p_bufr);
313 
314 	if (!panicstr)
315 		msgbuftrigger = 1;
316 
317 	critical_exit();
318 
319 	return (retval);
320 }
321 
322 int
323 vprintf(const char *fmt, va_list ap)
324 {
325 	struct putchar_arg pca;
326 	int retval;
327 
328 	critical_enter();
329 
330 	pca.tty = NULL;
331 	pca.flags = TOCONS | TOLOG;
332 	pca.pri = -1;
333 	pca.p_bufr = (char *) PCPU_PTR(cons_bufr);
334 	pca.p_next = pca.p_bufr;
335 	pca.n_bufr = PCPU_CONS_BUFR;
336 	pca.remain = PCPU_CONS_BUFR;
337 	*pca.p_next = '\0';
338 
339 	retval = kvprintf(fmt, putchar, &pca, 10, ap);
340 
341 	/* Write any buffered console output: */
342 	if (*pca.p_bufr != '\0')
343 		cnputs(pca.p_bufr);
344 
345 	if (!panicstr)
346 		msgbuftrigger = 1;
347 
348 	critical_exit();
349 
350 	return (retval);
351 }
352 
353 static void
354 putcons(int c, struct putchar_arg *ap)
355 {
356 	/* Check if no console output buffer was provided. */
357 	if (ap->p_bufr == NULL)
358 		/* Output direct to the console. */
359 		cnputc(c);
360 	else {
361 		/* Buffer the character: */
362 		if (c == '\n') {
363 			*ap->p_next++ = '\r';
364 			ap->remain--;
365 		}
366 		*ap->p_next++ = c;
367 		ap->remain--;
368 
369 		/* Always leave the buffer zero terminated. */
370 		*ap->p_next = '\0';
371 
372 		/* Check if the buffer needs to be flushed. */
373 		if (ap->remain < 3 || c == '\n') {
374 			cnputs(ap->p_bufr);
375 			ap->p_next = ap->p_bufr;
376 			ap->remain = ap->n_bufr;
377 			*ap->p_next = '\0';
378 		}
379 	}
380 }
381 
382 /*
383  * Print a character on console or users terminal.  If destination is
384  * the console then the last bunch of characters are saved in msgbuf for
385  * inspection later.
386  */
387 static void
388 putchar(int c, void *arg)
389 {
390 	struct putchar_arg *ap = (struct putchar_arg*) arg;
391 	struct tty *tp = ap->tty;
392 	int flags = ap->flags;
393 
394 	/* Don't use the tty code after a panic or while in ddb. */
395 	if (kdb_active) {
396 		if (c != '\0')
397 			cnputc(c);
398 	} else if (panicstr || ((flags & TOCONS) && constty == NULL)) {
399 		if (c != '\0')
400 			putcons(c, ap);
401 	} else {
402 		if ((flags & TOTTY) && tp != NULL)
403 			tputchar(c, tp);
404 		if (flags & TOCONS) {
405 			if (constty != NULL)
406 				msgbuf_addchar(&consmsgbuf, c);
407 			if (always_console_output && c != '\0')
408 				putcons(c, ap);
409 		}
410 	}
411 	if ((flags & TOLOG))
412 		msglogchar(c, ap->pri);
413 }
414 
415 /*
416  * Scaled down version of sprintf(3).
417  */
418 int
419 sprintf(char *buf, const char *cfmt, ...)
420 {
421 	int retval;
422 	va_list ap;
423 
424 	va_start(ap, cfmt);
425 	retval = kvprintf(cfmt, NULL, (void *)buf, 10, ap);
426 	buf[retval] = '\0';
427 	va_end(ap);
428 	return (retval);
429 }
430 
431 /*
432  * Scaled down version of vsprintf(3).
433  */
434 int
435 vsprintf(char *buf, const char *cfmt, va_list ap)
436 {
437 	int retval;
438 
439 	retval = kvprintf(cfmt, NULL, (void *)buf, 10, ap);
440 	buf[retval] = '\0';
441 	return (retval);
442 }
443 
444 /*
445  * Scaled down version of snprintf(3).
446  */
447 int
448 snprintf(char *str, size_t size, const char *format, ...)
449 {
450 	int retval;
451 	va_list ap;
452 
453 	va_start(ap, format);
454 	retval = vsnprintf(str, size, format, ap);
455 	va_end(ap);
456 	return(retval);
457 }
458 
459 /*
460  * Scaled down version of vsnprintf(3).
461  */
462 int
463 vsnprintf(char *str, size_t size, const char *format, va_list ap)
464 {
465 	struct snprintf_arg info;
466 	int retval;
467 
468 	info.str = str;
469 	info.remain = size;
470 	retval = kvprintf(format, snprintf_func, &info, 10, ap);
471 	if (info.remain >= 1)
472 		*info.str++ = '\0';
473 	return (retval);
474 }
475 
476 /*
477  * Kernel version which takes radix argument vsnprintf(3).
478  */
479 int
480 vsnrprintf(char *str, size_t size, int radix, const char *format, va_list ap)
481 {
482 	struct snprintf_arg info;
483 	int retval;
484 
485 	info.str = str;
486 	info.remain = size;
487 	retval = kvprintf(format, snprintf_func, &info, radix, ap);
488 	if (info.remain >= 1)
489 		*info.str++ = '\0';
490 	return (retval);
491 }
492 
493 static void
494 snprintf_func(int ch, void *arg)
495 {
496 	struct snprintf_arg *const info = arg;
497 
498 	if (info->remain >= 2) {
499 		*info->str++ = ch;
500 		info->remain--;
501 	}
502 }
503 
504 /*
505  * Put a NUL-terminated ASCII number (base <= 36) in a buffer in reverse
506  * order; return an optional length and a pointer to the last character
507  * written in the buffer (i.e., the first character of the string).
508  * The buffer pointed to by `nbuf' must have length >= MAXNBUF.
509  */
510 static char *
511 ksprintn(char *nbuf, uintmax_t num, int base, int *lenp, int upper)
512 {
513 	char *p, c;
514 
515 	p = nbuf;
516 	*p = '\0';
517 	do {
518 		c = hex2ascii(num % base);
519 		*++p = upper ? toupper(c) : c;
520 	} while (num /= base);
521 	if (lenp)
522 		*lenp = p - nbuf;
523 	return (p);
524 }
525 
526 /*
527  * Scaled down version of printf(3).
528  *
529  * Two additional formats:
530  *
531  * The format %b is supported to decode error registers.
532  * Its usage is:
533  *
534  *	printf("reg=%b\n", regval, "<base><arg>*");
535  *
536  * where <base> is the output base expressed as a control character, e.g.
537  * \10 gives octal; \20 gives hex.  Each arg is a sequence of characters,
538  * the first of which gives the bit number to be inspected (origin 1), and
539  * the next characters (up to a control character, i.e. a character <= 32),
540  * give the name of the register.  Thus:
541  *
542  *	kvprintf("reg=%b\n", 3, "\10\2BITTWO\1BITONE\n");
543  *
544  * would produce output:
545  *
546  *	reg=3<BITTWO,BITONE>
547  *
548  * XXX:  %D  -- Hexdump, takes pointer and separator string:
549  *		("%6D", ptr, ":")   -> XX:XX:XX:XX:XX:XX
550  *		("%*D", len, ptr, " " -> XX XX XX XX ...
551  */
552 int
553 kvprintf(char const *fmt, void (*func)(int, void*), void *arg, int radix, va_list ap)
554 {
555 #define PCHAR(c) {int cc=(c); if (func) (*func)(cc,arg); else *d++ = cc; retval++; }
556 	char nbuf[MAXNBUF];
557 	char *d;
558 	const char *p, *percent, *q;
559 	u_char *up;
560 	int ch, n;
561 	uintmax_t num;
562 	int base, lflag, qflag, tmp, width, ladjust, sharpflag, neg, sign, dot;
563 	int cflag, hflag, jflag, tflag, zflag;
564 	int dwidth, upper;
565 	char padc;
566 	int stop = 0, retval = 0;
567 
568 	num = 0;
569 	if (!func)
570 		d = (char *) arg;
571 	else
572 		d = NULL;
573 
574 	if (fmt == NULL)
575 		fmt = "(fmt null)\n";
576 
577 	if (radix < 2 || radix > 36)
578 		radix = 10;
579 
580 	for (;;) {
581 		padc = ' ';
582 		width = 0;
583 		while ((ch = (u_char)*fmt++) != '%' || stop) {
584 			if (ch == '\0')
585 				return (retval);
586 			PCHAR(ch);
587 		}
588 		percent = fmt - 1;
589 		qflag = 0; lflag = 0; ladjust = 0; sharpflag = 0; neg = 0;
590 		sign = 0; dot = 0; dwidth = 0; upper = 0;
591 		cflag = 0; hflag = 0; jflag = 0; tflag = 0; zflag = 0;
592 reswitch:	switch (ch = (u_char)*fmt++) {
593 		case '.':
594 			dot = 1;
595 			goto reswitch;
596 		case '#':
597 			sharpflag = 1;
598 			goto reswitch;
599 		case '+':
600 			sign = 1;
601 			goto reswitch;
602 		case '-':
603 			ladjust = 1;
604 			goto reswitch;
605 		case '%':
606 			PCHAR(ch);
607 			break;
608 		case '*':
609 			if (!dot) {
610 				width = va_arg(ap, int);
611 				if (width < 0) {
612 					ladjust = !ladjust;
613 					width = -width;
614 				}
615 			} else {
616 				dwidth = va_arg(ap, int);
617 			}
618 			goto reswitch;
619 		case '0':
620 			if (!dot) {
621 				padc = '0';
622 				goto reswitch;
623 			}
624 		case '1': case '2': case '3': case '4':
625 		case '5': case '6': case '7': case '8': case '9':
626 				for (n = 0;; ++fmt) {
627 					n = n * 10 + ch - '0';
628 					ch = *fmt;
629 					if (ch < '0' || ch > '9')
630 						break;
631 				}
632 			if (dot)
633 				dwidth = n;
634 			else
635 				width = n;
636 			goto reswitch;
637 		case 'b':
638 			num = (u_int)va_arg(ap, int);
639 			p = va_arg(ap, char *);
640 			for (q = ksprintn(nbuf, num, *p++, NULL, 0); *q;)
641 				PCHAR(*q--);
642 
643 			if (num == 0)
644 				break;
645 
646 			for (tmp = 0; *p;) {
647 				n = *p++;
648 				if (num & (1 << (n - 1))) {
649 					PCHAR(tmp ? ',' : '<');
650 					for (; (n = *p) > ' '; ++p)
651 						PCHAR(n);
652 					tmp = 1;
653 				} else
654 					for (; *p > ' '; ++p)
655 						continue;
656 			}
657 			if (tmp)
658 				PCHAR('>');
659 			break;
660 		case 'c':
661 			PCHAR(va_arg(ap, int));
662 			break;
663 		case 'D':
664 			up = va_arg(ap, u_char *);
665 			p = va_arg(ap, char *);
666 			if (!width)
667 				width = 16;
668 			while(width--) {
669 				PCHAR(hex2ascii(*up >> 4));
670 				PCHAR(hex2ascii(*up & 0x0f));
671 				up++;
672 				if (width)
673 					for (q=p;*q;q++)
674 						PCHAR(*q);
675 			}
676 			break;
677 		case 'd':
678 		case 'i':
679 			base = 10;
680 			sign = 1;
681 			goto handle_sign;
682 		case 'h':
683 			if (hflag) {
684 				hflag = 0;
685 				cflag = 1;
686 			} else
687 				hflag = 1;
688 			goto reswitch;
689 		case 'j':
690 			jflag = 1;
691 			goto reswitch;
692 		case 'l':
693 			if (lflag) {
694 				lflag = 0;
695 				qflag = 1;
696 			} else
697 				lflag = 1;
698 			goto reswitch;
699 		case 'n':
700 			if (jflag)
701 				*(va_arg(ap, intmax_t *)) = retval;
702 			else if (qflag)
703 				*(va_arg(ap, quad_t *)) = retval;
704 			else if (lflag)
705 				*(va_arg(ap, long *)) = retval;
706 			else if (zflag)
707 				*(va_arg(ap, size_t *)) = retval;
708 			else if (hflag)
709 				*(va_arg(ap, short *)) = retval;
710 			else if (cflag)
711 				*(va_arg(ap, char *)) = retval;
712 			else
713 				*(va_arg(ap, int *)) = retval;
714 			break;
715 		case 'o':
716 			base = 8;
717 			goto handle_nosign;
718 		case 'p':
719 			base = 16;
720 			sharpflag = (width == 0);
721 			sign = 0;
722 			num = (uintptr_t)va_arg(ap, void *);
723 			goto number;
724 		case 'q':
725 			qflag = 1;
726 			goto reswitch;
727 		case 'r':
728 			base = radix;
729 			if (sign)
730 				goto handle_sign;
731 			goto handle_nosign;
732 		case 's':
733 			p = va_arg(ap, char *);
734 			if (p == NULL)
735 				p = "(null)";
736 			if (!dot)
737 				n = strlen (p);
738 			else
739 				for (n = 0; n < dwidth && p[n]; n++)
740 					continue;
741 
742 			width -= n;
743 
744 			if (!ladjust && width > 0)
745 				while (width--)
746 					PCHAR(padc);
747 			while (n--)
748 				PCHAR(*p++);
749 			if (ladjust && width > 0)
750 				while (width--)
751 					PCHAR(padc);
752 			break;
753 		case 't':
754 			tflag = 1;
755 			goto reswitch;
756 		case 'u':
757 			base = 10;
758 			goto handle_nosign;
759 		case 'X':
760 			upper = 1;
761 		case 'x':
762 			base = 16;
763 			goto handle_nosign;
764 		case 'y':
765 			base = 16;
766 			sign = 1;
767 			goto handle_sign;
768 		case 'z':
769 			zflag = 1;
770 			goto reswitch;
771 handle_nosign:
772 			sign = 0;
773 			if (jflag)
774 				num = va_arg(ap, uintmax_t);
775 			else if (qflag)
776 				num = va_arg(ap, u_quad_t);
777 			else if (tflag)
778 				num = va_arg(ap, ptrdiff_t);
779 			else if (lflag)
780 				num = va_arg(ap, u_long);
781 			else if (zflag)
782 				num = va_arg(ap, size_t);
783 			else if (hflag)
784 				num = (u_short)va_arg(ap, int);
785 			else if (cflag)
786 				num = (u_char)va_arg(ap, int);
787 			else
788 				num = va_arg(ap, u_int);
789 			goto number;
790 handle_sign:
791 			if (jflag)
792 				num = va_arg(ap, intmax_t);
793 			else if (qflag)
794 				num = va_arg(ap, quad_t);
795 			else if (tflag)
796 				num = va_arg(ap, ptrdiff_t);
797 			else if (lflag)
798 				num = va_arg(ap, long);
799 			else if (zflag)
800 				num = va_arg(ap, size_t);
801 			else if (hflag)
802 				num = (short)va_arg(ap, int);
803 			else if (cflag)
804 				num = (char)va_arg(ap, int);
805 			else
806 				num = va_arg(ap, int);
807 number:
808 			if (sign && (intmax_t)num < 0) {
809 				neg = 1;
810 				num = -(intmax_t)num;
811 			}
812 			p = ksprintn(nbuf, num, base, &tmp, upper);
813 			if (sharpflag && num != 0) {
814 				if (base == 8)
815 					tmp++;
816 				else if (base == 16)
817 					tmp += 2;
818 			}
819 			if (neg)
820 				tmp++;
821 
822 			if (!ladjust && padc != '0' && width
823 			    && (width -= tmp) > 0)
824 				while (width--)
825 					PCHAR(padc);
826 			if (neg)
827 				PCHAR('-');
828 			if (sharpflag && num != 0) {
829 				if (base == 8) {
830 					PCHAR('0');
831 				} else if (base == 16) {
832 					PCHAR('0');
833 					PCHAR('x');
834 				}
835 			}
836 			if (!ladjust && width && (width -= tmp) > 0)
837 				while (width--)
838 					PCHAR(padc);
839 
840 			while (*p)
841 				PCHAR(*p--);
842 
843 			if (ladjust && width && (width -= tmp) > 0)
844 				while (width--)
845 					PCHAR(padc);
846 
847 			break;
848 		default:
849 			while (percent < fmt)
850 				PCHAR(*percent++);
851 			/*
852 			 * Since we ignore an formatting argument it is no
853 			 * longer safe to obey the remaining formatting
854 			 * arguments as the arguments will no longer match
855 			 * the format specs.
856 			 */
857 			stop = 1;
858 			break;
859 		}
860 	}
861 #undef PCHAR
862 }
863 
864 /*
865  * Put character in log buffer with a particular priority.
866  */
867 static void
868 msglogchar(int c, int pri)
869 {
870 	static int lastpri = -1;
871 	static int dangling;
872 	char nbuf[MAXNBUF];
873 	char *p;
874 
875 	if (!msgbufmapped)
876 		return;
877 	if (c == '\0' || c == '\r')
878 		return;
879 	if (pri != -1 && pri != lastpri) {
880 		if (dangling) {
881 			msgbuf_addchar(msgbufp, '\n');
882 			dangling = 0;
883 		}
884 		msgbuf_addchar(msgbufp, '<');
885 		for (p = ksprintn(nbuf, (uintmax_t)pri, 10, NULL, 0); *p;)
886 			msgbuf_addchar(msgbufp, *p--);
887 		msgbuf_addchar(msgbufp, '>');
888 		lastpri = pri;
889 	}
890 	msgbuf_addchar(msgbufp, c);
891 	if (c == '\n') {
892 		dangling = 0;
893 		lastpri = -1;
894 	} else {
895 		dangling = 1;
896 	}
897 }
898 
899 void
900 msgbufinit(void *ptr, int size)
901 {
902 	char *cp;
903 	static struct msgbuf *oldp = NULL;
904 
905 	size -= sizeof(*msgbufp);
906 	cp = (char *)ptr;
907 	msgbufp = (struct msgbuf *)(cp + size);
908 	msgbuf_reinit(msgbufp, cp, size);
909 	if (msgbufmapped && oldp != msgbufp)
910 		msgbuf_copy(oldp, msgbufp);
911 	msgbufmapped = 1;
912 	oldp = msgbufp;
913 }
914 
915 static int unprivileged_read_msgbuf = 1;
916 SYSCTL_INT(_security_bsd, OID_AUTO, unprivileged_read_msgbuf,
917     CTLFLAG_RW, &unprivileged_read_msgbuf, 0,
918     "Unprivileged processes may read the kernel message buffer");
919 
920 /* Sysctls for accessing/clearing the msgbuf */
921 static int
922 sysctl_kern_msgbuf(SYSCTL_HANDLER_ARGS)
923 {
924 	char buf[128];
925 	u_int seq;
926 	int error, len;
927 
928 	if (!unprivileged_read_msgbuf) {
929 		error = priv_check(req->td, PRIV_MSGBUF);
930 		if (error)
931 			return (error);
932 	}
933 
934 	/* Read the whole buffer, one chunk at a time. */
935 	msgbuf_peekbytes(msgbufp, NULL, 0, &seq);
936 	while ((len = msgbuf_peekbytes(msgbufp, buf, sizeof(buf), &seq)) > 0) {
937 		error = sysctl_handle_opaque(oidp, buf, len, req);
938 		if (error)
939 			return (error);
940 	}
941 	return (0);
942 }
943 
944 SYSCTL_PROC(_kern, OID_AUTO, msgbuf, CTLTYPE_STRING | CTLFLAG_RD,
945     0, 0, sysctl_kern_msgbuf, "A", "Contents of kernel message buffer");
946 
947 static int msgbuf_clearflag;
948 
949 static int
950 sysctl_kern_msgbuf_clear(SYSCTL_HANDLER_ARGS)
951 {
952 	int error;
953 	error = sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2, req);
954 	if (!error && req->newptr) {
955 		msgbuf_clear(msgbufp);
956 		msgbuf_clearflag = 0;
957 	}
958 	return (error);
959 }
960 
961 SYSCTL_PROC(_kern, OID_AUTO, msgbuf_clear,
962     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE, &msgbuf_clearflag, 0,
963     sysctl_kern_msgbuf_clear, "I", "Clear kernel message buffer");
964 
965 #ifdef DDB
966 
967 DB_SHOW_COMMAND(msgbuf, db_show_msgbuf)
968 {
969 	int i, j;
970 
971 	if (!msgbufmapped) {
972 		db_printf("msgbuf not mapped yet\n");
973 		return;
974 	}
975 	db_printf("msgbufp = %p\n", msgbufp);
976 	db_printf("magic = %x, size = %d, r= %u, w = %u, ptr = %p, cksum= %u\n",
977 	    msgbufp->msg_magic, msgbufp->msg_size, msgbufp->msg_rseq,
978 	    msgbufp->msg_wseq, msgbufp->msg_ptr, msgbufp->msg_cksum);
979 	for (i = 0; i < msgbufp->msg_size && !db_pager_quit; i++) {
980 		j = MSGBUF_SEQ_TO_POS(msgbufp, i + msgbufp->msg_rseq);
981 		db_printf("%c", msgbufp->msg_ptr[j]);
982 	}
983 	db_printf("\n");
984 }
985 
986 #endif /* DDB */
987 
988 void
989 hexdump(const void *ptr, int length, const char *hdr, int flags)
990 {
991 	int i, j, k;
992 	int cols;
993 	const unsigned char *cp;
994 	char delim;
995 
996 	if ((flags & HD_DELIM_MASK) != 0)
997 		delim = (flags & HD_DELIM_MASK) >> 8;
998 	else
999 		delim = ' ';
1000 
1001 	if ((flags & HD_COLUMN_MASK) != 0)
1002 		cols = flags & HD_COLUMN_MASK;
1003 	else
1004 		cols = 16;
1005 
1006 	cp = ptr;
1007 	for (i = 0; i < length; i+= cols) {
1008 		if (hdr != NULL)
1009 			printf("%s", hdr);
1010 
1011 		if ((flags & HD_OMIT_COUNT) == 0)
1012 			printf("%04x  ", i);
1013 
1014 		if ((flags & HD_OMIT_HEX) == 0) {
1015 			for (j = 0; j < cols; j++) {
1016 				k = i + j;
1017 				if (k < length)
1018 					printf("%c%02x", delim, cp[k]);
1019 				else
1020 					printf("   ");
1021 			}
1022 		}
1023 
1024 		if ((flags & HD_OMIT_CHARS) == 0) {
1025 			printf("  |");
1026 			for (j = 0; j < cols; j++) {
1027 				k = i + j;
1028 				if (k >= length)
1029 					printf(" ");
1030 				else if (cp[k] >= ' ' && cp[k] <= '~')
1031 					printf("%c", cp[k]);
1032 				else
1033 					printf(".");
1034 			}
1035 			printf("|");
1036 		}
1037 		printf("\n");
1038 	}
1039 }
1040 
1041