1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1986, 1988, 1991, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 * (c) UNIX System Laboratories, Inc.
7 * All or some portions of this file are derived from material licensed
8 * to the University of California by American Telephone and Telegraph
9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10 * the permission of UNIX System Laboratories, Inc.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 *    notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 *    notice, this list of conditions and the following disclaimer in the
19 *    documentation and/or other materials provided with the distribution.
20 * 3. Neither the name of the University nor the names of its contributors
21 *    may be used to endorse or promote products derived from this software
22 *    without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 *
36 *	@(#)subr_prf.c	8.3 (Berkeley) 1/21/94
37 */
38
39#include <sys/cdefs.h>
40__FBSDID("$FreeBSD$");
41
42#ifdef _KERNEL
43#include "opt_ddb.h"
44#include "opt_printf.h"
45#endif  /* _KERNEL */
46
47#include <sys/param.h>
48#ifdef _KERNEL
49#include <sys/systm.h>
50#include <sys/lock.h>
51#include <sys/kdb.h>
52#include <sys/mutex.h>
53#include <sys/sx.h>
54#include <sys/kernel.h>
55#include <sys/msgbuf.h>
56#include <sys/malloc.h>
57#include <sys/priv.h>
58#include <sys/proc.h>
59#include <sys/stddef.h>
60#include <sys/sysctl.h>
61#include <sys/tty.h>
62#include <sys/syslog.h>
63#include <sys/cons.h>
64#include <sys/uio.h>
65#else /* !_KERNEL */
66#include <errno.h>
67#endif
68#include <sys/ctype.h>
69#include <sys/sbuf.h>
70
71#ifdef DDB
72#include <ddb/ddb.h>
73#endif
74
75/*
76 * Note that stdarg.h and the ANSI style va_start macro is used for both
77 * ANSI and traditional C compilers.
78 */
79#ifdef _KERNEL
80#include <machine/stdarg.h>
81#else
82#include <stdarg.h>
83#endif
84
85/*
86 * This is needed for sbuf_putbuf() when compiled into userland.  Due to the
87 * shared nature of this file, it's the only place to put it.
88 */
89#ifndef _KERNEL
90#include <stdio.h>
91#endif
92
93#ifdef _KERNEL
94
95#define TOCONS	0x01
96#define TOTTY	0x02
97#define TOLOG	0x04
98
99/* Max number conversion buffer length: a u_quad_t in base 2, plus NUL byte. */
100#define MAXNBUF	(sizeof(intmax_t) * NBBY + 1)
101
102struct putchar_arg {
103	int	flags;
104	int	pri;
105	struct	tty *tty;
106	char	*p_bufr;
107	size_t	n_bufr;
108	char	*p_next;
109	size_t	remain;
110};
111
112struct snprintf_arg {
113	char	*str;
114	size_t	remain;
115};
116
117extern	int log_open;
118
119static void  msglogchar(int c, int pri);
120static void  msglogstr(char *str, int pri, int filter_cr);
121static void  putchar(int ch, void *arg);
122static char *ksprintn(char *nbuf, uintmax_t num, int base, int *len, int upper);
123static void  snprintf_func(int ch, void *arg);
124
125static bool msgbufmapped;		/* Set when safe to use msgbuf */
126int msgbuftrigger;
127struct msgbuf *msgbufp;
128
129#ifndef BOOT_TAG_SZ
130#define	BOOT_TAG_SZ	32
131#endif
132#ifndef BOOT_TAG
133/* Tag used to mark the start of a boot in dmesg */
134#define	BOOT_TAG	"---<<BOOT>>---"
135#endif
136
137static char current_boot_tag[BOOT_TAG_SZ + 1] = BOOT_TAG;
138SYSCTL_STRING(_kern, OID_AUTO, boot_tag, CTLFLAG_RDTUN | CTLFLAG_NOFETCH,
139    current_boot_tag, 0, "Tag added to dmesg at start of boot");
140
141static int log_console_output = 1;
142SYSCTL_INT(_kern, OID_AUTO, log_console_output, CTLFLAG_RWTUN,
143    &log_console_output, 0, "Duplicate console output to the syslog");
144
145/*
146 * See the comment in log_console() below for more explanation of this.
147 */
148static int log_console_add_linefeed;
149SYSCTL_INT(_kern, OID_AUTO, log_console_add_linefeed, CTLFLAG_RWTUN,
150    &log_console_add_linefeed, 0, "log_console() adds extra newlines");
151
152static int always_console_output;
153SYSCTL_INT(_kern, OID_AUTO, always_console_output, CTLFLAG_RWTUN,
154    &always_console_output, 0, "Always output to console despite TIOCCONS");
155
156/*
157 * Warn that a system table is full.
158 */
159void
160tablefull(const char *tab)
161{
162
163	log(LOG_ERR, "%s: table is full\n", tab);
164}
165
166/*
167 * Uprintf prints to the controlling terminal for the current process.
168 */
169int
170uprintf(const char *fmt, ...)
171{
172	va_list ap;
173	struct putchar_arg pca;
174	struct proc *p;
175	struct thread *td;
176	int retval;
177
178	td = curthread;
179	if (TD_IS_IDLETHREAD(td))
180		return (0);
181
182	sx_slock(&proctree_lock);
183	p = td->td_proc;
184	PROC_LOCK(p);
185	if ((p->p_flag & P_CONTROLT) == 0) {
186		PROC_UNLOCK(p);
187		sx_sunlock(&proctree_lock);
188		return (0);
189	}
190	SESS_LOCK(p->p_session);
191	pca.tty = p->p_session->s_ttyp;
192	SESS_UNLOCK(p->p_session);
193	PROC_UNLOCK(p);
194	if (pca.tty == NULL) {
195		sx_sunlock(&proctree_lock);
196		return (0);
197	}
198	pca.flags = TOTTY;
199	pca.p_bufr = NULL;
200	va_start(ap, fmt);
201	tty_lock(pca.tty);
202	sx_sunlock(&proctree_lock);
203	retval = kvprintf(fmt, putchar, &pca, 10, ap);
204	tty_unlock(pca.tty);
205	va_end(ap);
206	return (retval);
207}
208
209/*
210 * tprintf and vtprintf print on the controlling terminal associated with the
211 * given session, possibly to the log as well.
212 */
213void
214tprintf(struct proc *p, int pri, const char *fmt, ...)
215{
216	va_list ap;
217
218	va_start(ap, fmt);
219	vtprintf(p, pri, fmt, ap);
220	va_end(ap);
221}
222
223void
224vtprintf(struct proc *p, int pri, const char *fmt, va_list ap)
225{
226	struct tty *tp = NULL;
227	int flags = 0;
228	struct putchar_arg pca;
229	struct session *sess = NULL;
230
231	sx_slock(&proctree_lock);
232	if (pri != -1)
233		flags |= TOLOG;
234	if (p != NULL) {
235		PROC_LOCK(p);
236		if (p->p_flag & P_CONTROLT && p->p_session->s_ttyvp) {
237			sess = p->p_session;
238			sess_hold(sess);
239			PROC_UNLOCK(p);
240			tp = sess->s_ttyp;
241			if (tp != NULL && tty_checkoutq(tp))
242				flags |= TOTTY;
243			else
244				tp = NULL;
245		} else
246			PROC_UNLOCK(p);
247	}
248	pca.pri = pri;
249	pca.tty = tp;
250	pca.flags = flags;
251	pca.p_bufr = NULL;
252	if (pca.tty != NULL)
253		tty_lock(pca.tty);
254	sx_sunlock(&proctree_lock);
255	kvprintf(fmt, putchar, &pca, 10, ap);
256	if (pca.tty != NULL)
257		tty_unlock(pca.tty);
258	if (sess != NULL)
259		sess_release(sess);
260	msgbuftrigger = 1;
261}
262
263static int
264_vprintf(int level, int flags, const char *fmt, va_list ap)
265{
266	struct putchar_arg pca;
267	int retval;
268#ifdef PRINTF_BUFR_SIZE
269	char bufr[PRINTF_BUFR_SIZE];
270#endif
271
272	TSENTER();
273	pca.tty = NULL;
274	pca.pri = level;
275	pca.flags = flags;
276#ifdef PRINTF_BUFR_SIZE
277	pca.p_bufr = bufr;
278	pca.p_next = pca.p_bufr;
279	pca.n_bufr = sizeof(bufr);
280	pca.remain = sizeof(bufr);
281	*pca.p_next = '\0';
282#else
283	/* Don't buffer console output. */
284	pca.p_bufr = NULL;
285#endif
286
287	retval = kvprintf(fmt, putchar, &pca, 10, ap);
288
289#ifdef PRINTF_BUFR_SIZE
290	/* Write any buffered console/log output: */
291	if (*pca.p_bufr != '\0') {
292		if (pca.flags & TOLOG)
293			msglogstr(pca.p_bufr, level, /*filter_cr*/1);
294
295		if (pca.flags & TOCONS)
296			cnputs(pca.p_bufr);
297	}
298#endif
299
300	TSEXIT();
301	return (retval);
302}
303
304/*
305 * Log writes to the log buffer, and guarantees not to sleep (so can be
306 * called by interrupt routines).  If there is no process reading the
307 * log yet, it writes to the console also.
308 */
309void
310log(int level, const char *fmt, ...)
311{
312	va_list ap;
313
314	va_start(ap, fmt);
315	vlog(level, fmt, ap);
316	va_end(ap);
317}
318
319void
320vlog(int level, const char *fmt, va_list ap)
321{
322
323	(void)_vprintf(level, log_open ? TOLOG : TOCONS | TOLOG, fmt, ap);
324	msgbuftrigger = 1;
325}
326
327#define CONSCHUNK 128
328
329void
330log_console(struct uio *uio)
331{
332	int c, error, nl;
333	char *consbuffer;
334	int pri;
335
336	if (!log_console_output)
337		return;
338
339	pri = LOG_INFO | LOG_CONSOLE;
340	uio = cloneuio(uio);
341	consbuffer = malloc(CONSCHUNK, M_TEMP, M_WAITOK);
342
343	nl = 0;
344	while (uio->uio_resid > 0) {
345		c = imin(uio->uio_resid, CONSCHUNK - 1);
346		error = uiomove(consbuffer, c, uio);
347		if (error != 0)
348			break;
349		/* Make sure we're NUL-terminated */
350		consbuffer[c] = '\0';
351		if (consbuffer[c - 1] == '\n')
352			nl = 1;
353		else
354			nl = 0;
355		msglogstr(consbuffer, pri, /*filter_cr*/ 1);
356	}
357	/*
358	 * The previous behavior in log_console() is preserved when
359	 * log_console_add_linefeed is non-zero.  For that behavior, if an
360	 * individual console write came in that was not terminated with a
361	 * line feed, it would add a line feed.
362	 *
363	 * This results in different data in the message buffer than
364	 * appears on the system console (which doesn't add extra line feed
365	 * characters).
366	 *
367	 * A number of programs and rc scripts write a line feed, or a period
368	 * and a line feed when they have completed their operation.  On
369	 * the console, this looks seamless, but when displayed with
370	 * 'dmesg -a', you wind up with output that looks like this:
371	 *
372	 * Updating motd:
373	 * .
374	 *
375	 * On the console, it looks like this:
376	 * Updating motd:.
377	 *
378	 * We could add logic to detect that situation, or just not insert
379	 * the extra newlines.  Set the kern.log_console_add_linefeed
380	 * sysctl/tunable variable to get the old behavior.
381	 */
382	if (!nl && log_console_add_linefeed) {
383		consbuffer[0] = '\n';
384		consbuffer[1] = '\0';
385		msglogstr(consbuffer, pri, /*filter_cr*/ 1);
386	}
387	msgbuftrigger = 1;
388	free(uio, M_IOV);
389	free(consbuffer, M_TEMP);
390}
391
392int
393printf(const char *fmt, ...)
394{
395	va_list ap;
396	int retval;
397
398	va_start(ap, fmt);
399	retval = vprintf(fmt, ap);
400	va_end(ap);
401
402	return (retval);
403}
404
405int
406vprintf(const char *fmt, va_list ap)
407{
408	int retval;
409
410	retval = _vprintf(-1, TOCONS | TOLOG, fmt, ap);
411
412	if (!KERNEL_PANICKED())
413		msgbuftrigger = 1;
414
415	return (retval);
416}
417
418static void
419prf_putbuf(char *bufr, int flags, int pri)
420{
421
422	if (flags & TOLOG)
423		msglogstr(bufr, pri, /*filter_cr*/1);
424
425	if (flags & TOCONS) {
426		if ((!KERNEL_PANICKED()) && (constty != NULL))
427			msgbuf_addstr(&consmsgbuf, -1,
428			    bufr, /*filter_cr*/ 0);
429
430		if ((constty == NULL) ||(always_console_output))
431			cnputs(bufr);
432	}
433}
434
435static void
436putbuf(int c, struct putchar_arg *ap)
437{
438	/* Check if no console output buffer was provided. */
439	if (ap->p_bufr == NULL) {
440		/* Output direct to the console. */
441		if (ap->flags & TOCONS)
442			cnputc(c);
443
444		if (ap->flags & TOLOG)
445			msglogchar(c, ap->pri);
446	} else {
447		/* Buffer the character: */
448		*ap->p_next++ = c;
449		ap->remain--;
450
451		/* Always leave the buffer zero terminated. */
452		*ap->p_next = '\0';
453
454		/* Check if the buffer needs to be flushed. */
455		if (ap->remain == 2 || c == '\n') {
456			prf_putbuf(ap->p_bufr, ap->flags, ap->pri);
457
458			ap->p_next = ap->p_bufr;
459			ap->remain = ap->n_bufr;
460			*ap->p_next = '\0';
461		}
462
463		/*
464		 * Since we fill the buffer up one character at a time,
465		 * this should not happen.  We should always catch it when
466		 * ap->remain == 2 (if not sooner due to a newline), flush
467		 * the buffer and move on.  One way this could happen is
468		 * if someone sets PRINTF_BUFR_SIZE to 1 or something
469		 * similarly silly.
470		 */
471		KASSERT(ap->remain > 2, ("Bad buffer logic, remain = %zd",
472		    ap->remain));
473	}
474}
475
476/*
477 * Print a character on console or users terminal.  If destination is
478 * the console then the last bunch of characters are saved in msgbuf for
479 * inspection later.
480 */
481static void
482putchar(int c, void *arg)
483{
484	struct putchar_arg *ap = (struct putchar_arg*) arg;
485	struct tty *tp = ap->tty;
486	int flags = ap->flags;
487
488	/* Don't use the tty code after a panic or while in ddb. */
489	if (kdb_active) {
490		if (c != '\0')
491			cnputc(c);
492		return;
493	}
494
495	if ((flags & TOTTY) && tp != NULL && !KERNEL_PANICKED())
496		tty_putchar(tp, c);
497
498	if ((flags & (TOCONS | TOLOG)) && c != '\0')
499		putbuf(c, ap);
500}
501
502/*
503 * Scaled down version of sprintf(3).
504 */
505int
506sprintf(char *buf, const char *cfmt, ...)
507{
508	int retval;
509	va_list ap;
510
511	va_start(ap, cfmt);
512	retval = kvprintf(cfmt, NULL, (void *)buf, 10, ap);
513	buf[retval] = '\0';
514	va_end(ap);
515	return (retval);
516}
517
518/*
519 * Scaled down version of vsprintf(3).
520 */
521int
522vsprintf(char *buf, const char *cfmt, va_list ap)
523{
524	int retval;
525
526	retval = kvprintf(cfmt, NULL, (void *)buf, 10, ap);
527	buf[retval] = '\0';
528	return (retval);
529}
530
531/*
532 * Scaled down version of snprintf(3).
533 */
534int
535snprintf(char *str, size_t size, const char *format, ...)
536{
537	int retval;
538	va_list ap;
539
540	va_start(ap, format);
541	retval = vsnprintf(str, size, format, ap);
542	va_end(ap);
543	return(retval);
544}
545
546/*
547 * Scaled down version of vsnprintf(3).
548 */
549int
550vsnprintf(char *str, size_t size, const char *format, va_list ap)
551{
552	struct snprintf_arg info;
553	int retval;
554
555	info.str = str;
556	info.remain = size;
557	retval = kvprintf(format, snprintf_func, &info, 10, ap);
558	if (info.remain >= 1)
559		*info.str++ = '\0';
560	return (retval);
561}
562
563/*
564 * Kernel version which takes radix argument vsnprintf(3).
565 */
566int
567vsnrprintf(char *str, size_t size, int radix, const char *format, va_list ap)
568{
569	struct snprintf_arg info;
570	int retval;
571
572	info.str = str;
573	info.remain = size;
574	retval = kvprintf(format, snprintf_func, &info, radix, ap);
575	if (info.remain >= 1)
576		*info.str++ = '\0';
577	return (retval);
578}
579
580static void
581snprintf_func(int ch, void *arg)
582{
583	struct snprintf_arg *const info = arg;
584
585	if (info->remain >= 2) {
586		*info->str++ = ch;
587		info->remain--;
588	}
589}
590
591/*
592 * Put a NUL-terminated ASCII number (base <= 36) in a buffer in reverse
593 * order; return an optional length and a pointer to the last character
594 * written in the buffer (i.e., the first character of the string).
595 * The buffer pointed to by `nbuf' must have length >= MAXNBUF.
596 */
597static char *
598ksprintn(char *nbuf, uintmax_t num, int base, int *lenp, int upper)
599{
600	char *p, c;
601
602	p = nbuf;
603	*p = '\0';
604	do {
605		c = hex2ascii(num % base);
606		*++p = upper ? toupper(c) : c;
607	} while (num /= base);
608	if (lenp)
609		*lenp = p - nbuf;
610	return (p);
611}
612
613/*
614 * Scaled down version of printf(3).
615 *
616 * Two additional formats:
617 *
618 * The format %b is supported to decode error registers.
619 * Its usage is:
620 *
621 *	printf("reg=%b\n", regval, "<base><arg>*");
622 *
623 * where <base> is the output base expressed as a control character, e.g.
624 * \10 gives octal; \20 gives hex.  Each arg is a sequence of characters,
625 * the first of which gives the bit number to be inspected (origin 1), and
626 * the next characters (up to a control character, i.e. a character <= 32),
627 * give the name of the register.  Thus:
628 *
629 *	kvprintf("reg=%b\n", 3, "\10\2BITTWO\1BITONE");
630 *
631 * would produce output:
632 *
633 *	reg=3<BITTWO,BITONE>
634 *
635 * XXX:  %D  -- Hexdump, takes pointer and separator string:
636 *		("%6D", ptr, ":")   -> XX:XX:XX:XX:XX:XX
637 *		("%*D", len, ptr, " " -> XX XX XX XX ...
638 */
639int
640kvprintf(char const *fmt, void (*func)(int, void*), void *arg, int radix, va_list ap)
641{
642#define PCHAR(c) {int cc=(c); if (func) (*func)(cc,arg); else *d++ = cc; retval++; }
643	char nbuf[MAXNBUF];
644	char *d;
645	const char *p, *percent, *q;
646	u_char *up;
647	int ch, n;
648	uintmax_t num;
649	int base, lflag, qflag, tmp, width, ladjust, sharpflag, neg, sign, dot;
650	int cflag, hflag, jflag, tflag, zflag;
651	int bconv, dwidth, upper;
652	char padc;
653	int stop = 0, retval = 0;
654
655	num = 0;
656	q = NULL;
657	if (!func)
658		d = (char *) arg;
659	else
660		d = NULL;
661
662	if (fmt == NULL)
663		fmt = "(fmt null)\n";
664
665	if (radix < 2 || radix > 36)
666		radix = 10;
667
668	for (;;) {
669		padc = ' ';
670		width = 0;
671		while ((ch = (u_char)*fmt++) != '%' || stop) {
672			if (ch == '\0')
673				return (retval);
674			PCHAR(ch);
675		}
676		percent = fmt - 1;
677		qflag = 0; lflag = 0; ladjust = 0; sharpflag = 0; neg = 0;
678		sign = 0; dot = 0; bconv = 0; dwidth = 0; upper = 0;
679		cflag = 0; hflag = 0; jflag = 0; tflag = 0; zflag = 0;
680reswitch:	switch (ch = (u_char)*fmt++) {
681		case '.':
682			dot = 1;
683			goto reswitch;
684		case '#':
685			sharpflag = 1;
686			goto reswitch;
687		case '+':
688			sign = 1;
689			goto reswitch;
690		case '-':
691			ladjust = 1;
692			goto reswitch;
693		case '%':
694			PCHAR(ch);
695			break;
696		case '*':
697			if (!dot) {
698				width = va_arg(ap, int);
699				if (width < 0) {
700					ladjust = !ladjust;
701					width = -width;
702				}
703			} else {
704				dwidth = va_arg(ap, int);
705			}
706			goto reswitch;
707		case '0':
708			if (!dot) {
709				padc = '0';
710				goto reswitch;
711			}
712			/* FALLTHROUGH */
713		case '1': case '2': case '3': case '4':
714		case '5': case '6': case '7': case '8': case '9':
715				for (n = 0;; ++fmt) {
716					n = n * 10 + ch - '0';
717					ch = *fmt;
718					if (ch < '0' || ch > '9')
719						break;
720				}
721			if (dot)
722				dwidth = n;
723			else
724				width = n;
725			goto reswitch;
726		case 'b':
727			ladjust = 1;
728			bconv = 1;
729			goto handle_nosign;
730		case 'c':
731			width -= 1;
732
733			if (!ladjust && width > 0)
734				while (width--)
735					PCHAR(padc);
736			PCHAR(va_arg(ap, int));
737			if (ladjust && width > 0)
738				while (width--)
739					PCHAR(padc);
740			break;
741		case 'D':
742			up = va_arg(ap, u_char *);
743			p = va_arg(ap, char *);
744			if (!width)
745				width = 16;
746			while(width--) {
747				PCHAR(hex2ascii(*up >> 4));
748				PCHAR(hex2ascii(*up & 0x0f));
749				up++;
750				if (width)
751					for (q=p;*q;q++)
752						PCHAR(*q);
753			}
754			break;
755		case 'd':
756		case 'i':
757			base = 10;
758			sign = 1;
759			goto handle_sign;
760		case 'h':
761			if (hflag) {
762				hflag = 0;
763				cflag = 1;
764			} else
765				hflag = 1;
766			goto reswitch;
767		case 'j':
768			jflag = 1;
769			goto reswitch;
770		case 'l':
771			if (lflag) {
772				lflag = 0;
773				qflag = 1;
774			} else
775				lflag = 1;
776			goto reswitch;
777		case 'n':
778			/*
779			 * We do not support %n in kernel, but consume the
780			 * argument.
781			 */
782			if (jflag)
783				(void)va_arg(ap, intmax_t *);
784			else if (qflag)
785				(void)va_arg(ap, quad_t *);
786			else if (lflag)
787				(void)va_arg(ap, long *);
788			else if (zflag)
789				(void)va_arg(ap, size_t *);
790			else if (hflag)
791				(void)va_arg(ap, short *);
792			else if (cflag)
793				(void)va_arg(ap, char *);
794			else
795				(void)va_arg(ap, int *);
796			break;
797		case 'o':
798			base = 8;
799			goto handle_nosign;
800		case 'p':
801			base = 16;
802			sharpflag = (width == 0);
803			sign = 0;
804			num = (uintptr_t)va_arg(ap, void *);
805			goto number;
806		case 'q':
807			qflag = 1;
808			goto reswitch;
809		case 'r':
810			base = radix;
811			if (sign)
812				goto handle_sign;
813			goto handle_nosign;
814		case 's':
815			p = va_arg(ap, char *);
816			if (p == NULL)
817				p = "(null)";
818			if (!dot)
819				n = strlen (p);
820			else
821				for (n = 0; n < dwidth && p[n]; n++)
822					continue;
823
824			width -= n;
825
826			if (!ladjust && width > 0)
827				while (width--)
828					PCHAR(padc);
829			while (n--)
830				PCHAR(*p++);
831			if (ladjust && width > 0)
832				while (width--)
833					PCHAR(padc);
834			break;
835		case 't':
836			tflag = 1;
837			goto reswitch;
838		case 'u':
839			base = 10;
840			goto handle_nosign;
841		case 'X':
842			upper = 1;
843		case 'x':
844			base = 16;
845			goto handle_nosign;
846		case 'y':
847			base = 16;
848			sign = 1;
849			goto handle_sign;
850		case 'z':
851			zflag = 1;
852			goto reswitch;
853handle_nosign:
854			sign = 0;
855			if (jflag)
856				num = va_arg(ap, uintmax_t);
857			else if (qflag)
858				num = va_arg(ap, u_quad_t);
859			else if (tflag)
860				num = va_arg(ap, ptrdiff_t);
861			else if (lflag)
862				num = va_arg(ap, u_long);
863			else if (zflag)
864				num = va_arg(ap, size_t);
865			else if (hflag)
866				num = (u_short)va_arg(ap, int);
867			else if (cflag)
868				num = (u_char)va_arg(ap, int);
869			else
870				num = va_arg(ap, u_int);
871			if (bconv) {
872				q = va_arg(ap, char *);
873				base = *q++;
874			}
875			goto number;
876handle_sign:
877			if (jflag)
878				num = va_arg(ap, intmax_t);
879			else if (qflag)
880				num = va_arg(ap, quad_t);
881			else if (tflag)
882				num = va_arg(ap, ptrdiff_t);
883			else if (lflag)
884				num = va_arg(ap, long);
885			else if (zflag)
886				num = va_arg(ap, ssize_t);
887			else if (hflag)
888				num = (short)va_arg(ap, int);
889			else if (cflag)
890				num = (char)va_arg(ap, int);
891			else
892				num = va_arg(ap, int);
893number:
894			if (sign && (intmax_t)num < 0) {
895				neg = 1;
896				num = -(intmax_t)num;
897			}
898			p = ksprintn(nbuf, num, base, &n, upper);
899			tmp = 0;
900			if (sharpflag && num != 0) {
901				if (base == 8)
902					tmp++;
903				else if (base == 16)
904					tmp += 2;
905			}
906			if (neg)
907				tmp++;
908
909			if (!ladjust && padc == '0')
910				dwidth = width - tmp;
911			width -= tmp + imax(dwidth, n);
912			dwidth -= n;
913			if (!ladjust)
914				while (width-- > 0)
915					PCHAR(' ');
916			if (neg)
917				PCHAR('-');
918			if (sharpflag && num != 0) {
919				if (base == 8) {
920					PCHAR('0');
921				} else if (base == 16) {
922					PCHAR('0');
923					PCHAR('x');
924				}
925			}
926			while (dwidth-- > 0)
927				PCHAR('0');
928
929			while (*p)
930				PCHAR(*p--);
931
932			if (bconv && num != 0) {
933				/* %b conversion flag format. */
934				tmp = retval;
935				while (*q) {
936					n = *q++;
937					if (num & (1 << (n - 1))) {
938						PCHAR(retval != tmp ?
939						    ',' : '<');
940						for (; (n = *q) > ' '; ++q)
941							PCHAR(n);
942					} else
943						for (; *q > ' '; ++q)
944							continue;
945				}
946				if (retval != tmp) {
947					PCHAR('>');
948					width -= retval - tmp;
949				}
950			}
951
952			if (ladjust)
953				while (width-- > 0)
954					PCHAR(' ');
955
956			break;
957		default:
958			while (percent < fmt)
959				PCHAR(*percent++);
960			/*
961			 * Since we ignore a formatting argument it is no
962			 * longer safe to obey the remaining formatting
963			 * arguments as the arguments will no longer match
964			 * the format specs.
965			 */
966			stop = 1;
967			break;
968		}
969	}
970#undef PCHAR
971}
972
973/*
974 * Put character in log buffer with a particular priority.
975 */
976static void
977msglogchar(int c, int pri)
978{
979	static int lastpri = -1;
980	static int dangling;
981	char nbuf[MAXNBUF];
982	char *p;
983
984	if (!msgbufmapped)
985		return;
986	if (c == '\0' || c == '\r')
987		return;
988	if (pri != -1 && pri != lastpri) {
989		if (dangling) {
990			msgbuf_addchar(msgbufp, '\n');
991			dangling = 0;
992		}
993		msgbuf_addchar(msgbufp, '<');
994		for (p = ksprintn(nbuf, (uintmax_t)pri, 10, NULL, 0); *p;)
995			msgbuf_addchar(msgbufp, *p--);
996		msgbuf_addchar(msgbufp, '>');
997		lastpri = pri;
998	}
999	msgbuf_addchar(msgbufp, c);
1000	if (c == '\n') {
1001		dangling = 0;
1002		lastpri = -1;
1003	} else {
1004		dangling = 1;
1005	}
1006}
1007
1008static void
1009msglogstr(char *str, int pri, int filter_cr)
1010{
1011	if (!msgbufmapped)
1012		return;
1013
1014	msgbuf_addstr(msgbufp, pri, str, filter_cr);
1015}
1016
1017void
1018msgbufinit(void *ptr, int size)
1019{
1020	char *cp;
1021	static struct msgbuf *oldp = NULL;
1022	bool print_boot_tag;
1023
1024	size -= sizeof(*msgbufp);
1025	cp = (char *)ptr;
1026	print_boot_tag = !msgbufmapped;
1027	/* Attempt to fetch kern.boot_tag tunable on first mapping */
1028	if (!msgbufmapped)
1029		TUNABLE_STR_FETCH("kern.boot_tag", current_boot_tag,
1030		    sizeof(current_boot_tag));
1031	msgbufp = (struct msgbuf *)(cp + size);
1032	msgbuf_reinit(msgbufp, cp, size);
1033	if (msgbufmapped && oldp != msgbufp)
1034		msgbuf_copy(oldp, msgbufp);
1035	msgbufmapped = true;
1036	if (print_boot_tag && *current_boot_tag != '\0')
1037		printf("%s\n", current_boot_tag);
1038	oldp = msgbufp;
1039}
1040
1041/* Sysctls for accessing/clearing the msgbuf */
1042static int
1043sysctl_kern_msgbuf(SYSCTL_HANDLER_ARGS)
1044{
1045	char buf[128];
1046	u_int seq;
1047	int error, len;
1048
1049	error = priv_check(req->td, PRIV_MSGBUF);
1050	if (error)
1051		return (error);
1052
1053	/* Read the whole buffer, one chunk at a time. */
1054	mtx_lock(&msgbuf_lock);
1055	msgbuf_peekbytes(msgbufp, NULL, 0, &seq);
1056	for (;;) {
1057		len = msgbuf_peekbytes(msgbufp, buf, sizeof(buf), &seq);
1058		mtx_unlock(&msgbuf_lock);
1059		if (len == 0)
1060			return (SYSCTL_OUT(req, "", 1)); /* add nulterm */
1061
1062		error = sysctl_handle_opaque(oidp, buf, len, req);
1063		if (error)
1064			return (error);
1065
1066		mtx_lock(&msgbuf_lock);
1067	}
1068}
1069
1070SYSCTL_PROC(_kern, OID_AUTO, msgbuf,
1071    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
1072    NULL, 0, sysctl_kern_msgbuf, "A", "Contents of kernel message buffer");
1073
1074static int msgbuf_clearflag;
1075
1076static int
1077sysctl_kern_msgbuf_clear(SYSCTL_HANDLER_ARGS)
1078{
1079	int error;
1080	error = sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2, req);
1081	if (!error && req->newptr) {
1082		mtx_lock(&msgbuf_lock);
1083		msgbuf_clear(msgbufp);
1084		mtx_unlock(&msgbuf_lock);
1085		msgbuf_clearflag = 0;
1086	}
1087	return (error);
1088}
1089
1090SYSCTL_PROC(_kern, OID_AUTO, msgbuf_clear,
1091    CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE | CTLFLAG_MPSAFE,
1092    &msgbuf_clearflag, 0, sysctl_kern_msgbuf_clear, "I",
1093    "Clear kernel message buffer");
1094
1095#ifdef DDB
1096
1097DB_SHOW_COMMAND(msgbuf, db_show_msgbuf)
1098{
1099	int i, j;
1100
1101	if (!msgbufmapped) {
1102		db_printf("msgbuf not mapped yet\n");
1103		return;
1104	}
1105	db_printf("msgbufp = %p\n", msgbufp);
1106	db_printf("magic = %x, size = %d, r= %u, w = %u, ptr = %p, cksum= %u\n",
1107	    msgbufp->msg_magic, msgbufp->msg_size, msgbufp->msg_rseq,
1108	    msgbufp->msg_wseq, msgbufp->msg_ptr, msgbufp->msg_cksum);
1109	for (i = 0; i < msgbufp->msg_size && !db_pager_quit; i++) {
1110		j = MSGBUF_SEQ_TO_POS(msgbufp, i + msgbufp->msg_rseq);
1111		db_printf("%c", msgbufp->msg_ptr[j]);
1112	}
1113	db_printf("\n");
1114}
1115
1116#endif /* DDB */
1117
1118void
1119hexdump(const void *ptr, int length, const char *hdr, int flags)
1120{
1121	int i, j, k;
1122	int cols;
1123	const unsigned char *cp;
1124	char delim;
1125
1126	if ((flags & HD_DELIM_MASK) != 0)
1127		delim = (flags & HD_DELIM_MASK) >> 8;
1128	else
1129		delim = ' ';
1130
1131	if ((flags & HD_COLUMN_MASK) != 0)
1132		cols = flags & HD_COLUMN_MASK;
1133	else
1134		cols = 16;
1135
1136	cp = ptr;
1137	for (i = 0; i < length; i+= cols) {
1138		if (hdr != NULL)
1139			printf("%s", hdr);
1140
1141		if ((flags & HD_OMIT_COUNT) == 0)
1142			printf("%04x  ", i);
1143
1144		if ((flags & HD_OMIT_HEX) == 0) {
1145			for (j = 0; j < cols; j++) {
1146				k = i + j;
1147				if (k < length)
1148					printf("%c%02x", delim, cp[k]);
1149				else
1150					printf("   ");
1151			}
1152		}
1153
1154		if ((flags & HD_OMIT_CHARS) == 0) {
1155			printf("  |");
1156			for (j = 0; j < cols; j++) {
1157				k = i + j;
1158				if (k >= length)
1159					printf(" ");
1160				else if (cp[k] >= ' ' && cp[k] <= '~')
1161					printf("%c", cp[k]);
1162				else
1163					printf(".");
1164			}
1165			printf("|");
1166		}
1167		printf("\n");
1168	}
1169}
1170#endif /* _KERNEL */
1171
1172void
1173sbuf_hexdump(struct sbuf *sb, const void *ptr, int length, const char *hdr,
1174	     int flags)
1175{
1176	int i, j, k;
1177	int cols;
1178	const unsigned char *cp;
1179	char delim;
1180
1181	if ((flags & HD_DELIM_MASK) != 0)
1182		delim = (flags & HD_DELIM_MASK) >> 8;
1183	else
1184		delim = ' ';
1185
1186	if ((flags & HD_COLUMN_MASK) != 0)
1187		cols = flags & HD_COLUMN_MASK;
1188	else
1189		cols = 16;
1190
1191	cp = ptr;
1192	for (i = 0; i < length; i+= cols) {
1193		if (hdr != NULL)
1194			sbuf_printf(sb, "%s", hdr);
1195
1196		if ((flags & HD_OMIT_COUNT) == 0)
1197			sbuf_printf(sb, "%04x  ", i);
1198
1199		if ((flags & HD_OMIT_HEX) == 0) {
1200			for (j = 0; j < cols; j++) {
1201				k = i + j;
1202				if (k < length)
1203					sbuf_printf(sb, "%c%02x", delim, cp[k]);
1204				else
1205					sbuf_printf(sb, "   ");
1206			}
1207		}
1208
1209		if ((flags & HD_OMIT_CHARS) == 0) {
1210			sbuf_printf(sb, "  |");
1211			for (j = 0; j < cols; j++) {
1212				k = i + j;
1213				if (k >= length)
1214					sbuf_printf(sb, " ");
1215				else if (cp[k] >= ' ' && cp[k] <= '~')
1216					sbuf_printf(sb, "%c", cp[k]);
1217				else
1218					sbuf_printf(sb, ".");
1219			}
1220			sbuf_printf(sb, "|");
1221		}
1222		sbuf_printf(sb, "\n");
1223	}
1224}
1225
1226#ifdef _KERNEL
1227void
1228counted_warning(unsigned *counter, const char *msg)
1229{
1230	struct thread *td;
1231	unsigned c;
1232
1233	for (;;) {
1234		c = *counter;
1235		if (c == 0)
1236			break;
1237		if (atomic_cmpset_int(counter, c, c - 1)) {
1238			td = curthread;
1239			log(LOG_INFO, "pid %d (%s) %s%s\n",
1240			    td->td_proc->p_pid, td->td_name, msg,
1241			    c > 1 ? "" : " - not logging anymore");
1242			break;
1243		}
1244	}
1245}
1246#endif
1247
1248#ifdef _KERNEL
1249void
1250sbuf_putbuf(struct sbuf *sb)
1251{
1252
1253	prf_putbuf(sbuf_data(sb), TOLOG | TOCONS, -1);
1254}
1255#else
1256void
1257sbuf_putbuf(struct sbuf *sb)
1258{
1259
1260	printf("%s", sbuf_data(sb));
1261}
1262#endif
1263
1264int
1265sbuf_printf_drain(void *arg, const char *data, int len)
1266{
1267	size_t *retvalptr;
1268	int r;
1269#ifdef _KERNEL
1270	char *dataptr;
1271	char oldchr;
1272
1273	/*
1274	 * This is allowed as an extra byte is always resvered for
1275	 * terminating NUL byte.  Save and restore the byte because
1276	 * we might be flushing a record, and there may be valid
1277	 * data after the buffer.
1278	 */
1279	oldchr = data[len];
1280	dataptr = __DECONST(char *, data);
1281	dataptr[len] = '\0';
1282
1283	prf_putbuf(dataptr, TOLOG | TOCONS, -1);
1284	r = len;
1285
1286	dataptr[len] = oldchr;
1287
1288#else /* !_KERNEL */
1289
1290	r = printf("%.*s", len, data);
1291	if (r < 0)
1292		return (-errno);
1293
1294#endif
1295
1296	retvalptr = arg;
1297	if (retvalptr != NULL)
1298		*retvalptr += r;
1299
1300	return (r);
1301}
1302