xref: /freebsd/sys/kern/subr_prf.c (revision efe3b0de1438e7a8473d92f2be57072394559e3c)
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. 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 #ifdef _KERNEL
41 #include "opt_ddb.h"
42 #include "opt_printf.h"
43 #endif  /* _KERNEL */
44 
45 #include <sys/param.h>
46 #ifdef _KERNEL
47 #include <sys/systm.h>
48 #include <sys/lock.h>
49 #include <sys/kdb.h>
50 #include <sys/mutex.h>
51 #include <sys/sx.h>
52 #include <sys/kernel.h>
53 #include <sys/msgbuf.h>
54 #include <sys/malloc.h>
55 #include <sys/priv.h>
56 #include <sys/proc.h>
57 #include <sys/stddef.h>
58 #include <sys/sysctl.h>
59 #include <sys/tty.h>
60 #include <sys/syslog.h>
61 #include <sys/cons.h>
62 #include <sys/uio.h>
63 #endif
64 #include <sys/ctype.h>
65 #include <sys/sbuf.h>
66 
67 #ifdef DDB
68 #include <ddb/ddb.h>
69 #endif
70 
71 /*
72  * Note that stdarg.h and the ANSI style va_start macro is used for both
73  * ANSI and traditional C compilers.
74  */
75 #ifdef _KERNEL
76 #include <machine/stdarg.h>
77 #else
78 #include <stdarg.h>
79 #endif
80 
81 #ifdef _KERNEL
82 
83 #define TOCONS	0x01
84 #define TOTTY	0x02
85 #define TOLOG	0x04
86 
87 /* Max number conversion buffer length: a u_quad_t in base 2, plus NUL byte. */
88 #define MAXNBUF	(sizeof(intmax_t) * NBBY + 1)
89 
90 struct putchar_arg {
91 	int	flags;
92 	int	pri;
93 	struct	tty *tty;
94 	char	*p_bufr;
95 	size_t	n_bufr;
96 	char	*p_next;
97 	size_t	remain;
98 };
99 
100 struct snprintf_arg {
101 	char	*str;
102 	size_t	remain;
103 };
104 
105 extern	int log_open;
106 
107 static void  msglogchar(int c, int pri);
108 static void  msglogstr(char *str, int pri, int filter_cr);
109 static void  putchar(int ch, void *arg);
110 static char *ksprintn(char *nbuf, uintmax_t num, int base, int *len, int upper);
111 static void  snprintf_func(int ch, void *arg);
112 
113 static int msgbufmapped;		/* Set when safe to use msgbuf */
114 int msgbuftrigger;
115 
116 static int log_console_output = 1;
117 SYSCTL_INT(_kern, OID_AUTO, log_console_output, CTLFLAG_RWTUN,
118     &log_console_output, 0, "Duplicate console output to the syslog");
119 
120 /*
121  * See the comment in log_console() below for more explanation of this.
122  */
123 static int log_console_add_linefeed;
124 SYSCTL_INT(_kern, OID_AUTO, log_console_add_linefeed, CTLFLAG_RWTUN,
125     &log_console_add_linefeed, 0, "log_console() adds extra newlines");
126 
127 static int always_console_output;
128 SYSCTL_INT(_kern, OID_AUTO, always_console_output, CTLFLAG_RWTUN,
129     &always_console_output, 0, "Always output to console despite TIOCCONS");
130 
131 /*
132  * Warn that a system table is full.
133  */
134 void
135 tablefull(const char *tab)
136 {
137 
138 	log(LOG_ERR, "%s: table is full\n", tab);
139 }
140 
141 /*
142  * Uprintf prints to the controlling terminal for the current process.
143  */
144 int
145 uprintf(const char *fmt, ...)
146 {
147 	va_list ap;
148 	struct putchar_arg pca;
149 	struct proc *p;
150 	struct thread *td;
151 	int retval;
152 
153 	td = curthread;
154 	if (TD_IS_IDLETHREAD(td))
155 		return (0);
156 
157 	sx_slock(&proctree_lock);
158 	p = td->td_proc;
159 	PROC_LOCK(p);
160 	if ((p->p_flag & P_CONTROLT) == 0) {
161 		PROC_UNLOCK(p);
162 		sx_sunlock(&proctree_lock);
163 		return (0);
164 	}
165 	SESS_LOCK(p->p_session);
166 	pca.tty = p->p_session->s_ttyp;
167 	SESS_UNLOCK(p->p_session);
168 	PROC_UNLOCK(p);
169 	if (pca.tty == NULL) {
170 		sx_sunlock(&proctree_lock);
171 		return (0);
172 	}
173 	pca.flags = TOTTY;
174 	pca.p_bufr = NULL;
175 	va_start(ap, fmt);
176 	tty_lock(pca.tty);
177 	sx_sunlock(&proctree_lock);
178 	retval = kvprintf(fmt, putchar, &pca, 10, ap);
179 	tty_unlock(pca.tty);
180 	va_end(ap);
181 	return (retval);
182 }
183 
184 /*
185  * tprintf and vtprintf print on the controlling terminal associated with the
186  * given session, possibly to the log as well.
187  */
188 void
189 tprintf(struct proc *p, int pri, const char *fmt, ...)
190 {
191 	va_list ap;
192 
193 	va_start(ap, fmt);
194 	vtprintf(p, pri, fmt, ap);
195 	va_end(ap);
196 }
197 
198 void
199 vtprintf(struct proc *p, int pri, const char *fmt, va_list ap)
200 {
201 	struct tty *tp = NULL;
202 	int flags = 0;
203 	struct putchar_arg pca;
204 	struct session *sess = NULL;
205 
206 	sx_slock(&proctree_lock);
207 	if (pri != -1)
208 		flags |= TOLOG;
209 	if (p != NULL) {
210 		PROC_LOCK(p);
211 		if (p->p_flag & P_CONTROLT && p->p_session->s_ttyvp) {
212 			sess = p->p_session;
213 			sess_hold(sess);
214 			PROC_UNLOCK(p);
215 			tp = sess->s_ttyp;
216 			if (tp != NULL && tty_checkoutq(tp))
217 				flags |= TOTTY;
218 			else
219 				tp = NULL;
220 		} else
221 			PROC_UNLOCK(p);
222 	}
223 	pca.pri = pri;
224 	pca.tty = tp;
225 	pca.flags = flags;
226 	pca.p_bufr = NULL;
227 	if (pca.tty != NULL)
228 		tty_lock(pca.tty);
229 	sx_sunlock(&proctree_lock);
230 	kvprintf(fmt, putchar, &pca, 10, ap);
231 	if (pca.tty != NULL)
232 		tty_unlock(pca.tty);
233 	if (sess != NULL)
234 		sess_release(sess);
235 	msgbuftrigger = 1;
236 }
237 
238 /*
239  * Ttyprintf displays a message on a tty; it should be used only by
240  * the tty driver, or anything that knows the underlying tty will not
241  * be revoke(2)'d away.  Other callers should use tprintf.
242  */
243 int
244 ttyprintf(struct tty *tp, const char *fmt, ...)
245 {
246 	va_list ap;
247 	struct putchar_arg pca;
248 	int retval;
249 
250 	va_start(ap, fmt);
251 	pca.tty = tp;
252 	pca.flags = TOTTY;
253 	pca.p_bufr = NULL;
254 	retval = kvprintf(fmt, putchar, &pca, 10, ap);
255 	va_end(ap);
256 	return (retval);
257 }
258 
259 static int
260 _vprintf(int level, int flags, const char *fmt, va_list ap)
261 {
262 	struct putchar_arg pca;
263 	int retval;
264 #ifdef PRINTF_BUFR_SIZE
265 	char bufr[PRINTF_BUFR_SIZE];
266 #endif
267 
268 	pca.tty = NULL;
269 	pca.pri = level;
270 	pca.flags = flags;
271 #ifdef PRINTF_BUFR_SIZE
272 	pca.p_bufr = bufr;
273 	pca.p_next = pca.p_bufr;
274 	pca.n_bufr = sizeof(bufr);
275 	pca.remain = sizeof(bufr);
276 	*pca.p_next = '\0';
277 #else
278 	/* Don't buffer console output. */
279 	pca.p_bufr = NULL;
280 #endif
281 
282 	retval = kvprintf(fmt, putchar, &pca, 10, ap);
283 
284 #ifdef PRINTF_BUFR_SIZE
285 	/* Write any buffered console/log output: */
286 	if (*pca.p_bufr != '\0') {
287 		if (pca.flags & TOLOG)
288 			msglogstr(pca.p_bufr, level, /*filter_cr*/1);
289 
290 		if (pca.flags & TOCONS)
291 			cnputs(pca.p_bufr);
292 	}
293 #endif
294 
295 	return (retval);
296 }
297 
298 /*
299  * Log writes to the log buffer, and guarantees not to sleep (so can be
300  * called by interrupt routines).  If there is no process reading the
301  * log yet, it writes to the console also.
302  */
303 void
304 log(int level, const char *fmt, ...)
305 {
306 	va_list ap;
307 
308 	va_start(ap, fmt);
309 	vlog(level, fmt, ap);
310 	va_end(ap);
311 }
312 
313 void
314 vlog(int level, const char *fmt, va_list ap)
315 {
316 
317 	(void)_vprintf(level, log_open ? TOLOG : TOCONS | TOLOG, fmt, ap);
318 	msgbuftrigger = 1;
319 }
320 
321 #define CONSCHUNK 128
322 
323 void
324 log_console(struct uio *uio)
325 {
326 	int c, error, nl;
327 	char *consbuffer;
328 	int pri;
329 
330 	if (!log_console_output)
331 		return;
332 
333 	pri = LOG_INFO | LOG_CONSOLE;
334 	uio = cloneuio(uio);
335 	consbuffer = malloc(CONSCHUNK, M_TEMP, M_WAITOK);
336 
337 	nl = 0;
338 	while (uio->uio_resid > 0) {
339 		c = imin(uio->uio_resid, CONSCHUNK - 1);
340 		error = uiomove(consbuffer, c, uio);
341 		if (error != 0)
342 			break;
343 		/* Make sure we're NUL-terminated */
344 		consbuffer[c] = '\0';
345 		if (consbuffer[c - 1] == '\n')
346 			nl = 1;
347 		else
348 			nl = 0;
349 		msglogstr(consbuffer, pri, /*filter_cr*/ 1);
350 	}
351 	/*
352 	 * The previous behavior in log_console() is preserved when
353 	 * log_console_add_linefeed is non-zero.  For that behavior, if an
354 	 * individual console write came in that was not terminated with a
355 	 * line feed, it would add a line feed.
356 	 *
357 	 * This results in different data in the message buffer than
358 	 * appears on the system console (which doesn't add extra line feed
359 	 * characters).
360 	 *
361 	 * A number of programs and rc scripts write a line feed, or a period
362 	 * and a line feed when they have completed their operation.  On
363 	 * the console, this looks seamless, but when displayed with
364 	 * 'dmesg -a', you wind up with output that looks like this:
365 	 *
366 	 * Updating motd:
367 	 * .
368 	 *
369 	 * On the console, it looks like this:
370 	 * Updating motd:.
371 	 *
372 	 * We could add logic to detect that situation, or just not insert
373 	 * the extra newlines.  Set the kern.log_console_add_linefeed
374 	 * sysctl/tunable variable to get the old behavior.
375 	 */
376 	if (!nl && log_console_add_linefeed) {
377 		consbuffer[0] = '\n';
378 		consbuffer[1] = '\0';
379 		msglogstr(consbuffer, pri, /*filter_cr*/ 1);
380 	}
381 	msgbuftrigger = 1;
382 	free(uio, M_IOV);
383 	free(consbuffer, M_TEMP);
384 	return;
385 }
386 
387 int
388 printf(const char *fmt, ...)
389 {
390 	va_list ap;
391 	int retval;
392 
393 	va_start(ap, fmt);
394 	retval = vprintf(fmt, ap);
395 	va_end(ap);
396 
397 	return (retval);
398 }
399 
400 int
401 vprintf(const char *fmt, va_list ap)
402 {
403 	int retval;
404 
405 	retval = _vprintf(-1, TOCONS | TOLOG, fmt, ap);
406 
407 	if (!panicstr)
408 		msgbuftrigger = 1;
409 
410 	return (retval);
411 }
412 
413 static void
414 putbuf(int c, struct putchar_arg *ap)
415 {
416 	/* Check if no console output buffer was provided. */
417 	if (ap->p_bufr == NULL) {
418 		/* Output direct to the console. */
419 		if (ap->flags & TOCONS)
420 			cnputc(c);
421 
422 		if (ap->flags & TOLOG)
423 			msglogchar(c, ap->pri);
424 	} else {
425 		/* Buffer the character: */
426 		*ap->p_next++ = c;
427 		ap->remain--;
428 
429 		/* Always leave the buffer zero terminated. */
430 		*ap->p_next = '\0';
431 
432 		/* Check if the buffer needs to be flushed. */
433 		if (ap->remain == 2 || c == '\n') {
434 
435 			if (ap->flags & TOLOG)
436 				msglogstr(ap->p_bufr, ap->pri, /*filter_cr*/1);
437 
438 			if (ap->flags & TOCONS) {
439 				if ((panicstr == NULL) && (constty != NULL))
440 					msgbuf_addstr(&consmsgbuf, -1,
441 					    ap->p_bufr, /*filter_cr*/ 0);
442 
443 				if ((constty == NULL) ||(always_console_output))
444 					cnputs(ap->p_bufr);
445 			}
446 
447 			ap->p_next = ap->p_bufr;
448 			ap->remain = ap->n_bufr;
449 			*ap->p_next = '\0';
450 		}
451 
452 		/*
453 		 * Since we fill the buffer up one character at a time,
454 		 * this should not happen.  We should always catch it when
455 		 * ap->remain == 2 (if not sooner due to a newline), flush
456 		 * the buffer and move on.  One way this could happen is
457 		 * if someone sets PRINTF_BUFR_SIZE to 1 or something
458 		 * similarly silly.
459 		 */
460 		KASSERT(ap->remain > 2, ("Bad buffer logic, remain = %zd",
461 		    ap->remain));
462 	}
463 }
464 
465 /*
466  * Print a character on console or users terminal.  If destination is
467  * the console then the last bunch of characters are saved in msgbuf for
468  * inspection later.
469  */
470 static void
471 putchar(int c, void *arg)
472 {
473 	struct putchar_arg *ap = (struct putchar_arg*) arg;
474 	struct tty *tp = ap->tty;
475 	int flags = ap->flags;
476 
477 	/* Don't use the tty code after a panic or while in ddb. */
478 	if (kdb_active) {
479 		if (c != '\0')
480 			cnputc(c);
481 		return;
482 	}
483 
484 	if ((flags & TOTTY) && tp != NULL && panicstr == NULL)
485 		tty_putchar(tp, c);
486 
487 	if ((flags & (TOCONS | TOLOG)) && c != '\0')
488 		putbuf(c, ap);
489 }
490 
491 /*
492  * Scaled down version of sprintf(3).
493  */
494 int
495 sprintf(char *buf, const char *cfmt, ...)
496 {
497 	int retval;
498 	va_list ap;
499 
500 	va_start(ap, cfmt);
501 	retval = kvprintf(cfmt, NULL, (void *)buf, 10, ap);
502 	buf[retval] = '\0';
503 	va_end(ap);
504 	return (retval);
505 }
506 
507 /*
508  * Scaled down version of vsprintf(3).
509  */
510 int
511 vsprintf(char *buf, const char *cfmt, va_list ap)
512 {
513 	int retval;
514 
515 	retval = kvprintf(cfmt, NULL, (void *)buf, 10, ap);
516 	buf[retval] = '\0';
517 	return (retval);
518 }
519 
520 /*
521  * Scaled down version of snprintf(3).
522  */
523 int
524 snprintf(char *str, size_t size, const char *format, ...)
525 {
526 	int retval;
527 	va_list ap;
528 
529 	va_start(ap, format);
530 	retval = vsnprintf(str, size, format, ap);
531 	va_end(ap);
532 	return(retval);
533 }
534 
535 /*
536  * Scaled down version of vsnprintf(3).
537  */
538 int
539 vsnprintf(char *str, size_t size, const char *format, va_list ap)
540 {
541 	struct snprintf_arg info;
542 	int retval;
543 
544 	info.str = str;
545 	info.remain = size;
546 	retval = kvprintf(format, snprintf_func, &info, 10, ap);
547 	if (info.remain >= 1)
548 		*info.str++ = '\0';
549 	return (retval);
550 }
551 
552 /*
553  * Kernel version which takes radix argument vsnprintf(3).
554  */
555 int
556 vsnrprintf(char *str, size_t size, int radix, const char *format, va_list ap)
557 {
558 	struct snprintf_arg info;
559 	int retval;
560 
561 	info.str = str;
562 	info.remain = size;
563 	retval = kvprintf(format, snprintf_func, &info, radix, ap);
564 	if (info.remain >= 1)
565 		*info.str++ = '\0';
566 	return (retval);
567 }
568 
569 static void
570 snprintf_func(int ch, void *arg)
571 {
572 	struct snprintf_arg *const info = arg;
573 
574 	if (info->remain >= 2) {
575 		*info->str++ = ch;
576 		info->remain--;
577 	}
578 }
579 
580 /*
581  * Put a NUL-terminated ASCII number (base <= 36) in a buffer in reverse
582  * order; return an optional length and a pointer to the last character
583  * written in the buffer (i.e., the first character of the string).
584  * The buffer pointed to by `nbuf' must have length >= MAXNBUF.
585  */
586 static char *
587 ksprintn(char *nbuf, uintmax_t num, int base, int *lenp, int upper)
588 {
589 	char *p, c;
590 
591 	p = nbuf;
592 	*p = '\0';
593 	do {
594 		c = hex2ascii(num % base);
595 		*++p = upper ? toupper(c) : c;
596 	} while (num /= base);
597 	if (lenp)
598 		*lenp = p - nbuf;
599 	return (p);
600 }
601 
602 /*
603  * Scaled down version of printf(3).
604  *
605  * Two additional formats:
606  *
607  * The format %b is supported to decode error registers.
608  * Its usage is:
609  *
610  *	printf("reg=%b\n", regval, "<base><arg>*");
611  *
612  * where <base> is the output base expressed as a control character, e.g.
613  * \10 gives octal; \20 gives hex.  Each arg is a sequence of characters,
614  * the first of which gives the bit number to be inspected (origin 1), and
615  * the next characters (up to a control character, i.e. a character <= 32),
616  * give the name of the register.  Thus:
617  *
618  *	kvprintf("reg=%b\n", 3, "\10\2BITTWO\1BITONE");
619  *
620  * would produce output:
621  *
622  *	reg=3<BITTWO,BITONE>
623  *
624  * XXX:  %D  -- Hexdump, takes pointer and separator string:
625  *		("%6D", ptr, ":")   -> XX:XX:XX:XX:XX:XX
626  *		("%*D", len, ptr, " " -> XX XX XX XX ...
627  */
628 int
629 kvprintf(char const *fmt, void (*func)(int, void*), void *arg, int radix, va_list ap)
630 {
631 #define PCHAR(c) {int cc=(c); if (func) (*func)(cc,arg); else *d++ = cc; retval++; }
632 	char nbuf[MAXNBUF];
633 	char *d;
634 	const char *p, *percent, *q;
635 	u_char *up;
636 	int ch, n;
637 	uintmax_t num;
638 	int base, lflag, qflag, tmp, width, ladjust, sharpflag, neg, sign, dot;
639 	int cflag, hflag, jflag, tflag, zflag;
640 	int dwidth, upper;
641 	char padc;
642 	int stop = 0, retval = 0;
643 
644 	num = 0;
645 	if (!func)
646 		d = (char *) arg;
647 	else
648 		d = NULL;
649 
650 	if (fmt == NULL)
651 		fmt = "(fmt null)\n";
652 
653 	if (radix < 2 || radix > 36)
654 		radix = 10;
655 
656 	for (;;) {
657 		padc = ' ';
658 		width = 0;
659 		while ((ch = (u_char)*fmt++) != '%' || stop) {
660 			if (ch == '\0')
661 				return (retval);
662 			PCHAR(ch);
663 		}
664 		percent = fmt - 1;
665 		qflag = 0; lflag = 0; ladjust = 0; sharpflag = 0; neg = 0;
666 		sign = 0; dot = 0; dwidth = 0; upper = 0;
667 		cflag = 0; hflag = 0; jflag = 0; tflag = 0; zflag = 0;
668 reswitch:	switch (ch = (u_char)*fmt++) {
669 		case '.':
670 			dot = 1;
671 			goto reswitch;
672 		case '#':
673 			sharpflag = 1;
674 			goto reswitch;
675 		case '+':
676 			sign = 1;
677 			goto reswitch;
678 		case '-':
679 			ladjust = 1;
680 			goto reswitch;
681 		case '%':
682 			PCHAR(ch);
683 			break;
684 		case '*':
685 			if (!dot) {
686 				width = va_arg(ap, int);
687 				if (width < 0) {
688 					ladjust = !ladjust;
689 					width = -width;
690 				}
691 			} else {
692 				dwidth = va_arg(ap, int);
693 			}
694 			goto reswitch;
695 		case '0':
696 			if (!dot) {
697 				padc = '0';
698 				goto reswitch;
699 			}
700 		case '1': case '2': case '3': case '4':
701 		case '5': case '6': case '7': case '8': case '9':
702 				for (n = 0;; ++fmt) {
703 					n = n * 10 + ch - '0';
704 					ch = *fmt;
705 					if (ch < '0' || ch > '9')
706 						break;
707 				}
708 			if (dot)
709 				dwidth = n;
710 			else
711 				width = n;
712 			goto reswitch;
713 		case 'b':
714 			num = (u_int)va_arg(ap, int);
715 			p = va_arg(ap, char *);
716 			for (q = ksprintn(nbuf, num, *p++, NULL, 0); *q;)
717 				PCHAR(*q--);
718 
719 			if (num == 0)
720 				break;
721 
722 			for (tmp = 0; *p;) {
723 				n = *p++;
724 				if (num & (1 << (n - 1))) {
725 					PCHAR(tmp ? ',' : '<');
726 					for (; (n = *p) > ' '; ++p)
727 						PCHAR(n);
728 					tmp = 1;
729 				} else
730 					for (; *p > ' '; ++p)
731 						continue;
732 			}
733 			if (tmp)
734 				PCHAR('>');
735 			break;
736 		case 'c':
737 			width -= 1;
738 
739 			if (!ladjust && width > 0)
740 				while (width--)
741 					PCHAR(padc);
742 			PCHAR(va_arg(ap, int));
743 			if (ladjust && width > 0)
744 				while (width--)
745 					PCHAR(padc);
746 			break;
747 		case 'D':
748 			up = va_arg(ap, u_char *);
749 			p = va_arg(ap, char *);
750 			if (!width)
751 				width = 16;
752 			while(width--) {
753 				PCHAR(hex2ascii(*up >> 4));
754 				PCHAR(hex2ascii(*up & 0x0f));
755 				up++;
756 				if (width)
757 					for (q=p;*q;q++)
758 						PCHAR(*q);
759 			}
760 			break;
761 		case 'd':
762 		case 'i':
763 			base = 10;
764 			sign = 1;
765 			goto handle_sign;
766 		case 'h':
767 			if (hflag) {
768 				hflag = 0;
769 				cflag = 1;
770 			} else
771 				hflag = 1;
772 			goto reswitch;
773 		case 'j':
774 			jflag = 1;
775 			goto reswitch;
776 		case 'l':
777 			if (lflag) {
778 				lflag = 0;
779 				qflag = 1;
780 			} else
781 				lflag = 1;
782 			goto reswitch;
783 		case 'n':
784 			if (jflag)
785 				*(va_arg(ap, intmax_t *)) = retval;
786 			else if (qflag)
787 				*(va_arg(ap, quad_t *)) = retval;
788 			else if (lflag)
789 				*(va_arg(ap, long *)) = retval;
790 			else if (zflag)
791 				*(va_arg(ap, size_t *)) = retval;
792 			else if (hflag)
793 				*(va_arg(ap, short *)) = retval;
794 			else if (cflag)
795 				*(va_arg(ap, char *)) = retval;
796 			else
797 				*(va_arg(ap, int *)) = retval;
798 			break;
799 		case 'o':
800 			base = 8;
801 			goto handle_nosign;
802 		case 'p':
803 			base = 16;
804 			sharpflag = (width == 0);
805 			sign = 0;
806 			num = (uintptr_t)va_arg(ap, void *);
807 			goto number;
808 		case 'q':
809 			qflag = 1;
810 			goto reswitch;
811 		case 'r':
812 			base = radix;
813 			if (sign)
814 				goto handle_sign;
815 			goto handle_nosign;
816 		case 's':
817 			p = va_arg(ap, char *);
818 			if (p == NULL)
819 				p = "(null)";
820 			if (!dot)
821 				n = strlen (p);
822 			else
823 				for (n = 0; n < dwidth && p[n]; n++)
824 					continue;
825 
826 			width -= n;
827 
828 			if (!ladjust && width > 0)
829 				while (width--)
830 					PCHAR(padc);
831 			while (n--)
832 				PCHAR(*p++);
833 			if (ladjust && width > 0)
834 				while (width--)
835 					PCHAR(padc);
836 			break;
837 		case 't':
838 			tflag = 1;
839 			goto reswitch;
840 		case 'u':
841 			base = 10;
842 			goto handle_nosign;
843 		case 'X':
844 			upper = 1;
845 		case 'x':
846 			base = 16;
847 			goto handle_nosign;
848 		case 'y':
849 			base = 16;
850 			sign = 1;
851 			goto handle_sign;
852 		case 'z':
853 			zflag = 1;
854 			goto reswitch;
855 handle_nosign:
856 			sign = 0;
857 			if (jflag)
858 				num = va_arg(ap, uintmax_t);
859 			else if (qflag)
860 				num = va_arg(ap, u_quad_t);
861 			else if (tflag)
862 				num = va_arg(ap, ptrdiff_t);
863 			else if (lflag)
864 				num = va_arg(ap, u_long);
865 			else if (zflag)
866 				num = va_arg(ap, size_t);
867 			else if (hflag)
868 				num = (u_short)va_arg(ap, int);
869 			else if (cflag)
870 				num = (u_char)va_arg(ap, int);
871 			else
872 				num = va_arg(ap, u_int);
873 			goto number;
874 handle_sign:
875 			if (jflag)
876 				num = va_arg(ap, intmax_t);
877 			else if (qflag)
878 				num = va_arg(ap, quad_t);
879 			else if (tflag)
880 				num = va_arg(ap, ptrdiff_t);
881 			else if (lflag)
882 				num = va_arg(ap, long);
883 			else if (zflag)
884 				num = va_arg(ap, ssize_t);
885 			else if (hflag)
886 				num = (short)va_arg(ap, int);
887 			else if (cflag)
888 				num = (char)va_arg(ap, int);
889 			else
890 				num = va_arg(ap, int);
891 number:
892 			if (sign && (intmax_t)num < 0) {
893 				neg = 1;
894 				num = -(intmax_t)num;
895 			}
896 			p = ksprintn(nbuf, num, base, &n, upper);
897 			tmp = 0;
898 			if (sharpflag && num != 0) {
899 				if (base == 8)
900 					tmp++;
901 				else if (base == 16)
902 					tmp += 2;
903 			}
904 			if (neg)
905 				tmp++;
906 
907 			if (!ladjust && padc == '0')
908 				dwidth = width - tmp;
909 			width -= tmp + imax(dwidth, n);
910 			dwidth -= n;
911 			if (!ladjust)
912 				while (width-- > 0)
913 					PCHAR(' ');
914 			if (neg)
915 				PCHAR('-');
916 			if (sharpflag && num != 0) {
917 				if (base == 8) {
918 					PCHAR('0');
919 				} else if (base == 16) {
920 					PCHAR('0');
921 					PCHAR('x');
922 				}
923 			}
924 			while (dwidth-- > 0)
925 				PCHAR('0');
926 
927 			while (*p)
928 				PCHAR(*p--);
929 
930 			if (ladjust)
931 				while (width-- > 0)
932 					PCHAR(' ');
933 
934 			break;
935 		default:
936 			while (percent < fmt)
937 				PCHAR(*percent++);
938 			/*
939 			 * Since we ignore a formatting argument it is no
940 			 * longer safe to obey the remaining formatting
941 			 * arguments as the arguments will no longer match
942 			 * the format specs.
943 			 */
944 			stop = 1;
945 			break;
946 		}
947 	}
948 #undef PCHAR
949 }
950 
951 /*
952  * Put character in log buffer with a particular priority.
953  */
954 static void
955 msglogchar(int c, int pri)
956 {
957 	static int lastpri = -1;
958 	static int dangling;
959 	char nbuf[MAXNBUF];
960 	char *p;
961 
962 	if (!msgbufmapped)
963 		return;
964 	if (c == '\0' || c == '\r')
965 		return;
966 	if (pri != -1 && pri != lastpri) {
967 		if (dangling) {
968 			msgbuf_addchar(msgbufp, '\n');
969 			dangling = 0;
970 		}
971 		msgbuf_addchar(msgbufp, '<');
972 		for (p = ksprintn(nbuf, (uintmax_t)pri, 10, NULL, 0); *p;)
973 			msgbuf_addchar(msgbufp, *p--);
974 		msgbuf_addchar(msgbufp, '>');
975 		lastpri = pri;
976 	}
977 	msgbuf_addchar(msgbufp, c);
978 	if (c == '\n') {
979 		dangling = 0;
980 		lastpri = -1;
981 	} else {
982 		dangling = 1;
983 	}
984 }
985 
986 static void
987 msglogstr(char *str, int pri, int filter_cr)
988 {
989 	if (!msgbufmapped)
990 		return;
991 
992 	msgbuf_addstr(msgbufp, pri, str, filter_cr);
993 }
994 
995 void
996 msgbufinit(void *ptr, int size)
997 {
998 	char *cp;
999 	static struct msgbuf *oldp = NULL;
1000 
1001 	size -= sizeof(*msgbufp);
1002 	cp = (char *)ptr;
1003 	msgbufp = (struct msgbuf *)(cp + size);
1004 	msgbuf_reinit(msgbufp, cp, size);
1005 	if (msgbufmapped && oldp != msgbufp)
1006 		msgbuf_copy(oldp, msgbufp);
1007 	msgbufmapped = 1;
1008 	oldp = msgbufp;
1009 }
1010 
1011 static int unprivileged_read_msgbuf = 1;
1012 SYSCTL_INT(_security_bsd, OID_AUTO, unprivileged_read_msgbuf,
1013     CTLFLAG_RW, &unprivileged_read_msgbuf, 0,
1014     "Unprivileged processes may read the kernel message buffer");
1015 
1016 /* Sysctls for accessing/clearing the msgbuf */
1017 static int
1018 sysctl_kern_msgbuf(SYSCTL_HANDLER_ARGS)
1019 {
1020 	char buf[128];
1021 	u_int seq;
1022 	int error, len;
1023 
1024 	if (!unprivileged_read_msgbuf) {
1025 		error = priv_check(req->td, PRIV_MSGBUF);
1026 		if (error)
1027 			return (error);
1028 	}
1029 
1030 	/* Read the whole buffer, one chunk at a time. */
1031 	mtx_lock(&msgbuf_lock);
1032 	msgbuf_peekbytes(msgbufp, NULL, 0, &seq);
1033 	for (;;) {
1034 		len = msgbuf_peekbytes(msgbufp, buf, sizeof(buf), &seq);
1035 		mtx_unlock(&msgbuf_lock);
1036 		if (len == 0)
1037 			return (SYSCTL_OUT(req, "", 1)); /* add nulterm */
1038 
1039 		error = sysctl_handle_opaque(oidp, buf, len, req);
1040 		if (error)
1041 			return (error);
1042 
1043 		mtx_lock(&msgbuf_lock);
1044 	}
1045 }
1046 
1047 SYSCTL_PROC(_kern, OID_AUTO, msgbuf,
1048     CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
1049     NULL, 0, sysctl_kern_msgbuf, "A", "Contents of kernel message buffer");
1050 
1051 static int msgbuf_clearflag;
1052 
1053 static int
1054 sysctl_kern_msgbuf_clear(SYSCTL_HANDLER_ARGS)
1055 {
1056 	int error;
1057 	error = sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2, req);
1058 	if (!error && req->newptr) {
1059 		mtx_lock(&msgbuf_lock);
1060 		msgbuf_clear(msgbufp);
1061 		mtx_unlock(&msgbuf_lock);
1062 		msgbuf_clearflag = 0;
1063 	}
1064 	return (error);
1065 }
1066 
1067 SYSCTL_PROC(_kern, OID_AUTO, msgbuf_clear,
1068     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE | CTLFLAG_MPSAFE,
1069     &msgbuf_clearflag, 0, sysctl_kern_msgbuf_clear, "I",
1070     "Clear kernel message buffer");
1071 
1072 #ifdef DDB
1073 
1074 DB_SHOW_COMMAND(msgbuf, db_show_msgbuf)
1075 {
1076 	int i, j;
1077 
1078 	if (!msgbufmapped) {
1079 		db_printf("msgbuf not mapped yet\n");
1080 		return;
1081 	}
1082 	db_printf("msgbufp = %p\n", msgbufp);
1083 	db_printf("magic = %x, size = %d, r= %u, w = %u, ptr = %p, cksum= %u\n",
1084 	    msgbufp->msg_magic, msgbufp->msg_size, msgbufp->msg_rseq,
1085 	    msgbufp->msg_wseq, msgbufp->msg_ptr, msgbufp->msg_cksum);
1086 	for (i = 0; i < msgbufp->msg_size && !db_pager_quit; i++) {
1087 		j = MSGBUF_SEQ_TO_POS(msgbufp, i + msgbufp->msg_rseq);
1088 		db_printf("%c", msgbufp->msg_ptr[j]);
1089 	}
1090 	db_printf("\n");
1091 }
1092 
1093 #endif /* DDB */
1094 
1095 void
1096 hexdump(const void *ptr, int length, const char *hdr, int flags)
1097 {
1098 	int i, j, k;
1099 	int cols;
1100 	const unsigned char *cp;
1101 	char delim;
1102 
1103 	if ((flags & HD_DELIM_MASK) != 0)
1104 		delim = (flags & HD_DELIM_MASK) >> 8;
1105 	else
1106 		delim = ' ';
1107 
1108 	if ((flags & HD_COLUMN_MASK) != 0)
1109 		cols = flags & HD_COLUMN_MASK;
1110 	else
1111 		cols = 16;
1112 
1113 	cp = ptr;
1114 	for (i = 0; i < length; i+= cols) {
1115 		if (hdr != NULL)
1116 			printf("%s", hdr);
1117 
1118 		if ((flags & HD_OMIT_COUNT) == 0)
1119 			printf("%04x  ", i);
1120 
1121 		if ((flags & HD_OMIT_HEX) == 0) {
1122 			for (j = 0; j < cols; j++) {
1123 				k = i + j;
1124 				if (k < length)
1125 					printf("%c%02x", delim, cp[k]);
1126 				else
1127 					printf("   ");
1128 			}
1129 		}
1130 
1131 		if ((flags & HD_OMIT_CHARS) == 0) {
1132 			printf("  |");
1133 			for (j = 0; j < cols; j++) {
1134 				k = i + j;
1135 				if (k >= length)
1136 					printf(" ");
1137 				else if (cp[k] >= ' ' && cp[k] <= '~')
1138 					printf("%c", cp[k]);
1139 				else
1140 					printf(".");
1141 			}
1142 			printf("|");
1143 		}
1144 		printf("\n");
1145 	}
1146 }
1147 #endif /* _KERNEL */
1148 
1149 void
1150 sbuf_hexdump(struct sbuf *sb, const void *ptr, int length, const char *hdr,
1151 	     int flags)
1152 {
1153 	int i, j, k;
1154 	int cols;
1155 	const unsigned char *cp;
1156 	char delim;
1157 
1158 	if ((flags & HD_DELIM_MASK) != 0)
1159 		delim = (flags & HD_DELIM_MASK) >> 8;
1160 	else
1161 		delim = ' ';
1162 
1163 	if ((flags & HD_COLUMN_MASK) != 0)
1164 		cols = flags & HD_COLUMN_MASK;
1165 	else
1166 		cols = 16;
1167 
1168 	cp = ptr;
1169 	for (i = 0; i < length; i+= cols) {
1170 		if (hdr != NULL)
1171 			sbuf_printf(sb, "%s", hdr);
1172 
1173 		if ((flags & HD_OMIT_COUNT) == 0)
1174 			sbuf_printf(sb, "%04x  ", i);
1175 
1176 		if ((flags & HD_OMIT_HEX) == 0) {
1177 			for (j = 0; j < cols; j++) {
1178 				k = i + j;
1179 				if (k < length)
1180 					sbuf_printf(sb, "%c%02x", delim, cp[k]);
1181 				else
1182 					sbuf_printf(sb, "   ");
1183 			}
1184 		}
1185 
1186 		if ((flags & HD_OMIT_CHARS) == 0) {
1187 			sbuf_printf(sb, "  |");
1188 			for (j = 0; j < cols; j++) {
1189 				k = i + j;
1190 				if (k >= length)
1191 					sbuf_printf(sb, " ");
1192 				else if (cp[k] >= ' ' && cp[k] <= '~')
1193 					sbuf_printf(sb, "%c", cp[k]);
1194 				else
1195 					sbuf_printf(sb, ".");
1196 			}
1197 			sbuf_printf(sb, "|");
1198 		}
1199 		sbuf_printf(sb, "\n");
1200 	}
1201 }
1202 
1203 #ifdef _KERNEL
1204 void
1205 counted_warning(unsigned *counter, const char *msg)
1206 {
1207 	struct thread *td;
1208 	unsigned c;
1209 
1210 	for (;;) {
1211 		c = *counter;
1212 		if (c == 0)
1213 			break;
1214 		if (atomic_cmpset_int(counter, c, c - 1)) {
1215 			td = curthread;
1216 			log(LOG_INFO, "pid %d (%s) %s%s\n",
1217 			    td->td_proc->p_pid, td->td_name, msg,
1218 			    c > 1 ? "" : " - not logging anymore");
1219 			break;
1220 		}
1221 	}
1222 }
1223 #endif
1224