xref: /freebsd/sys/kern/subr_prf.c (revision ef36b3f75658d201edb495068db5e1be49593de5)
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 /*
82  * This is needed for sbuf_putbuf() when compiled into userland.  Due to the
83  * shared nature of this file, it's the only place to put it.
84  */
85 #ifndef _KERNEL
86 #include <stdio.h>
87 #endif
88 
89 #ifdef _KERNEL
90 
91 #define TOCONS	0x01
92 #define TOTTY	0x02
93 #define TOLOG	0x04
94 
95 /* Max number conversion buffer length: a u_quad_t in base 2, plus NUL byte. */
96 #define MAXNBUF	(sizeof(intmax_t) * NBBY + 1)
97 
98 struct putchar_arg {
99 	int	flags;
100 	int	pri;
101 	struct	tty *tty;
102 	char	*p_bufr;
103 	size_t	n_bufr;
104 	char	*p_next;
105 	size_t	remain;
106 };
107 
108 struct snprintf_arg {
109 	char	*str;
110 	size_t	remain;
111 };
112 
113 extern	int log_open;
114 
115 static void  msglogchar(int c, int pri);
116 static void  msglogstr(char *str, int pri, int filter_cr);
117 static void  putchar(int ch, void *arg);
118 static char *ksprintn(char *nbuf, uintmax_t num, int base, int *len, int upper);
119 static void  snprintf_func(int ch, void *arg);
120 
121 static int msgbufmapped;		/* Set when safe to use msgbuf */
122 int msgbuftrigger;
123 
124 static int log_console_output = 1;
125 SYSCTL_INT(_kern, OID_AUTO, log_console_output, CTLFLAG_RWTUN,
126     &log_console_output, 0, "Duplicate console output to the syslog");
127 
128 /*
129  * See the comment in log_console() below for more explanation of this.
130  */
131 static int log_console_add_linefeed;
132 SYSCTL_INT(_kern, OID_AUTO, log_console_add_linefeed, CTLFLAG_RWTUN,
133     &log_console_add_linefeed, 0, "log_console() adds extra newlines");
134 
135 static int always_console_output;
136 SYSCTL_INT(_kern, OID_AUTO, always_console_output, CTLFLAG_RWTUN,
137     &always_console_output, 0, "Always output to console despite TIOCCONS");
138 
139 /*
140  * Warn that a system table is full.
141  */
142 void
143 tablefull(const char *tab)
144 {
145 
146 	log(LOG_ERR, "%s: table is full\n", tab);
147 }
148 
149 /*
150  * Uprintf prints to the controlling terminal for the current process.
151  */
152 int
153 uprintf(const char *fmt, ...)
154 {
155 	va_list ap;
156 	struct putchar_arg pca;
157 	struct proc *p;
158 	struct thread *td;
159 	int retval;
160 
161 	td = curthread;
162 	if (TD_IS_IDLETHREAD(td))
163 		return (0);
164 
165 	sx_slock(&proctree_lock);
166 	p = td->td_proc;
167 	PROC_LOCK(p);
168 	if ((p->p_flag & P_CONTROLT) == 0) {
169 		PROC_UNLOCK(p);
170 		sx_sunlock(&proctree_lock);
171 		return (0);
172 	}
173 	SESS_LOCK(p->p_session);
174 	pca.tty = p->p_session->s_ttyp;
175 	SESS_UNLOCK(p->p_session);
176 	PROC_UNLOCK(p);
177 	if (pca.tty == NULL) {
178 		sx_sunlock(&proctree_lock);
179 		return (0);
180 	}
181 	pca.flags = TOTTY;
182 	pca.p_bufr = NULL;
183 	va_start(ap, fmt);
184 	tty_lock(pca.tty);
185 	sx_sunlock(&proctree_lock);
186 	retval = kvprintf(fmt, putchar, &pca, 10, ap);
187 	tty_unlock(pca.tty);
188 	va_end(ap);
189 	return (retval);
190 }
191 
192 /*
193  * tprintf and vtprintf print on the controlling terminal associated with the
194  * given session, possibly to the log as well.
195  */
196 void
197 tprintf(struct proc *p, int pri, const char *fmt, ...)
198 {
199 	va_list ap;
200 
201 	va_start(ap, fmt);
202 	vtprintf(p, pri, fmt, ap);
203 	va_end(ap);
204 }
205 
206 void
207 vtprintf(struct proc *p, int pri, const char *fmt, va_list ap)
208 {
209 	struct tty *tp = NULL;
210 	int flags = 0;
211 	struct putchar_arg pca;
212 	struct session *sess = NULL;
213 
214 	sx_slock(&proctree_lock);
215 	if (pri != -1)
216 		flags |= TOLOG;
217 	if (p != NULL) {
218 		PROC_LOCK(p);
219 		if (p->p_flag & P_CONTROLT && p->p_session->s_ttyvp) {
220 			sess = p->p_session;
221 			sess_hold(sess);
222 			PROC_UNLOCK(p);
223 			tp = sess->s_ttyp;
224 			if (tp != NULL && tty_checkoutq(tp))
225 				flags |= TOTTY;
226 			else
227 				tp = NULL;
228 		} else
229 			PROC_UNLOCK(p);
230 	}
231 	pca.pri = pri;
232 	pca.tty = tp;
233 	pca.flags = flags;
234 	pca.p_bufr = NULL;
235 	if (pca.tty != NULL)
236 		tty_lock(pca.tty);
237 	sx_sunlock(&proctree_lock);
238 	kvprintf(fmt, putchar, &pca, 10, ap);
239 	if (pca.tty != NULL)
240 		tty_unlock(pca.tty);
241 	if (sess != NULL)
242 		sess_release(sess);
243 	msgbuftrigger = 1;
244 }
245 
246 /*
247  * Ttyprintf displays a message on a tty; it should be used only by
248  * the tty driver, or anything that knows the underlying tty will not
249  * be revoke(2)'d away.  Other callers should use tprintf.
250  */
251 int
252 ttyprintf(struct tty *tp, const char *fmt, ...)
253 {
254 	va_list ap;
255 	struct putchar_arg pca;
256 	int retval;
257 
258 	va_start(ap, fmt);
259 	pca.tty = tp;
260 	pca.flags = TOTTY;
261 	pca.p_bufr = NULL;
262 	retval = kvprintf(fmt, putchar, &pca, 10, ap);
263 	va_end(ap);
264 	return (retval);
265 }
266 
267 static int
268 _vprintf(int level, int flags, const char *fmt, va_list ap)
269 {
270 	struct putchar_arg pca;
271 	int retval;
272 #ifdef PRINTF_BUFR_SIZE
273 	char bufr[PRINTF_BUFR_SIZE];
274 #endif
275 
276 	pca.tty = NULL;
277 	pca.pri = level;
278 	pca.flags = flags;
279 #ifdef PRINTF_BUFR_SIZE
280 	pca.p_bufr = bufr;
281 	pca.p_next = pca.p_bufr;
282 	pca.n_bufr = sizeof(bufr);
283 	pca.remain = sizeof(bufr);
284 	*pca.p_next = '\0';
285 #else
286 	/* Don't buffer console output. */
287 	pca.p_bufr = NULL;
288 #endif
289 
290 	retval = kvprintf(fmt, putchar, &pca, 10, ap);
291 
292 #ifdef PRINTF_BUFR_SIZE
293 	/* Write any buffered console/log output: */
294 	if (*pca.p_bufr != '\0') {
295 		if (pca.flags & TOLOG)
296 			msglogstr(pca.p_bufr, level, /*filter_cr*/1);
297 
298 		if (pca.flags & TOCONS)
299 			cnputs(pca.p_bufr);
300 	}
301 #endif
302 
303 	return (retval);
304 }
305 
306 /*
307  * Log writes to the log buffer, and guarantees not to sleep (so can be
308  * called by interrupt routines).  If there is no process reading the
309  * log yet, it writes to the console also.
310  */
311 void
312 log(int level, const char *fmt, ...)
313 {
314 	va_list ap;
315 
316 	va_start(ap, fmt);
317 	vlog(level, fmt, ap);
318 	va_end(ap);
319 }
320 
321 void
322 vlog(int level, const char *fmt, va_list ap)
323 {
324 
325 	(void)_vprintf(level, log_open ? TOLOG : TOCONS | TOLOG, fmt, ap);
326 	msgbuftrigger = 1;
327 }
328 
329 #define CONSCHUNK 128
330 
331 void
332 log_console(struct uio *uio)
333 {
334 	int c, error, nl;
335 	char *consbuffer;
336 	int pri;
337 
338 	if (!log_console_output)
339 		return;
340 
341 	pri = LOG_INFO | LOG_CONSOLE;
342 	uio = cloneuio(uio);
343 	consbuffer = malloc(CONSCHUNK, M_TEMP, M_WAITOK);
344 
345 	nl = 0;
346 	while (uio->uio_resid > 0) {
347 		c = imin(uio->uio_resid, CONSCHUNK - 1);
348 		error = uiomove(consbuffer, c, uio);
349 		if (error != 0)
350 			break;
351 		/* Make sure we're NUL-terminated */
352 		consbuffer[c] = '\0';
353 		if (consbuffer[c - 1] == '\n')
354 			nl = 1;
355 		else
356 			nl = 0;
357 		msglogstr(consbuffer, pri, /*filter_cr*/ 1);
358 	}
359 	/*
360 	 * The previous behavior in log_console() is preserved when
361 	 * log_console_add_linefeed is non-zero.  For that behavior, if an
362 	 * individual console write came in that was not terminated with a
363 	 * line feed, it would add a line feed.
364 	 *
365 	 * This results in different data in the message buffer than
366 	 * appears on the system console (which doesn't add extra line feed
367 	 * characters).
368 	 *
369 	 * A number of programs and rc scripts write a line feed, or a period
370 	 * and a line feed when they have completed their operation.  On
371 	 * the console, this looks seamless, but when displayed with
372 	 * 'dmesg -a', you wind up with output that looks like this:
373 	 *
374 	 * Updating motd:
375 	 * .
376 	 *
377 	 * On the console, it looks like this:
378 	 * Updating motd:.
379 	 *
380 	 * We could add logic to detect that situation, or just not insert
381 	 * the extra newlines.  Set the kern.log_console_add_linefeed
382 	 * sysctl/tunable variable to get the old behavior.
383 	 */
384 	if (!nl && log_console_add_linefeed) {
385 		consbuffer[0] = '\n';
386 		consbuffer[1] = '\0';
387 		msglogstr(consbuffer, pri, /*filter_cr*/ 1);
388 	}
389 	msgbuftrigger = 1;
390 	free(uio, M_IOV);
391 	free(consbuffer, M_TEMP);
392 }
393 
394 int
395 printf(const char *fmt, ...)
396 {
397 	va_list ap;
398 	int retval;
399 
400 	va_start(ap, fmt);
401 	retval = vprintf(fmt, ap);
402 	va_end(ap);
403 
404 	return (retval);
405 }
406 
407 int
408 vprintf(const char *fmt, va_list ap)
409 {
410 	int retval;
411 
412 	retval = _vprintf(-1, TOCONS | TOLOG, fmt, ap);
413 
414 	if (!panicstr)
415 		msgbuftrigger = 1;
416 
417 	return (retval);
418 }
419 
420 static void
421 prf_putbuf(char *bufr, int flags, int pri)
422 {
423 
424 	if (flags & TOLOG)
425 		msglogstr(bufr, pri, /*filter_cr*/1);
426 
427 	if (flags & TOCONS) {
428 		if ((panicstr == NULL) && (constty != NULL))
429 			msgbuf_addstr(&consmsgbuf, -1,
430 			    bufr, /*filter_cr*/ 0);
431 
432 		if ((constty == NULL) ||(always_console_output))
433 			cnputs(bufr);
434 	}
435 }
436 
437 static void
438 putbuf(int c, struct putchar_arg *ap)
439 {
440 	/* Check if no console output buffer was provided. */
441 	if (ap->p_bufr == NULL) {
442 		/* Output direct to the console. */
443 		if (ap->flags & TOCONS)
444 			cnputc(c);
445 
446 		if (ap->flags & TOLOG)
447 			msglogchar(c, ap->pri);
448 	} else {
449 		/* Buffer the character: */
450 		*ap->p_next++ = c;
451 		ap->remain--;
452 
453 		/* Always leave the buffer zero terminated. */
454 		*ap->p_next = '\0';
455 
456 		/* Check if the buffer needs to be flushed. */
457 		if (ap->remain == 2 || c == '\n') {
458 			prf_putbuf(ap->p_bufr, ap->flags, ap->pri);
459 
460 			ap->p_next = ap->p_bufr;
461 			ap->remain = ap->n_bufr;
462 			*ap->p_next = '\0';
463 		}
464 
465 		/*
466 		 * Since we fill the buffer up one character at a time,
467 		 * this should not happen.  We should always catch it when
468 		 * ap->remain == 2 (if not sooner due to a newline), flush
469 		 * the buffer and move on.  One way this could happen is
470 		 * if someone sets PRINTF_BUFR_SIZE to 1 or something
471 		 * similarly silly.
472 		 */
473 		KASSERT(ap->remain > 2, ("Bad buffer logic, remain = %zd",
474 		    ap->remain));
475 	}
476 }
477 
478 /*
479  * Print a character on console or users terminal.  If destination is
480  * the console then the last bunch of characters are saved in msgbuf for
481  * inspection later.
482  */
483 static void
484 putchar(int c, void *arg)
485 {
486 	struct putchar_arg *ap = (struct putchar_arg*) arg;
487 	struct tty *tp = ap->tty;
488 	int flags = ap->flags;
489 
490 	/* Don't use the tty code after a panic or while in ddb. */
491 	if (kdb_active) {
492 		if (c != '\0')
493 			cnputc(c);
494 		return;
495 	}
496 
497 	if ((flags & TOTTY) && tp != NULL && panicstr == NULL)
498 		tty_putchar(tp, c);
499 
500 	if ((flags & (TOCONS | TOLOG)) && c != '\0')
501 		putbuf(c, ap);
502 }
503 
504 /*
505  * Scaled down version of sprintf(3).
506  */
507 int
508 sprintf(char *buf, const char *cfmt, ...)
509 {
510 	int retval;
511 	va_list ap;
512 
513 	va_start(ap, cfmt);
514 	retval = kvprintf(cfmt, NULL, (void *)buf, 10, ap);
515 	buf[retval] = '\0';
516 	va_end(ap);
517 	return (retval);
518 }
519 
520 /*
521  * Scaled down version of vsprintf(3).
522  */
523 int
524 vsprintf(char *buf, const char *cfmt, va_list ap)
525 {
526 	int retval;
527 
528 	retval = kvprintf(cfmt, NULL, (void *)buf, 10, ap);
529 	buf[retval] = '\0';
530 	return (retval);
531 }
532 
533 /*
534  * Scaled down version of snprintf(3).
535  */
536 int
537 snprintf(char *str, size_t size, const char *format, ...)
538 {
539 	int retval;
540 	va_list ap;
541 
542 	va_start(ap, format);
543 	retval = vsnprintf(str, size, format, ap);
544 	va_end(ap);
545 	return(retval);
546 }
547 
548 /*
549  * Scaled down version of vsnprintf(3).
550  */
551 int
552 vsnprintf(char *str, size_t size, const char *format, va_list ap)
553 {
554 	struct snprintf_arg info;
555 	int retval;
556 
557 	info.str = str;
558 	info.remain = size;
559 	retval = kvprintf(format, snprintf_func, &info, 10, ap);
560 	if (info.remain >= 1)
561 		*info.str++ = '\0';
562 	return (retval);
563 }
564 
565 /*
566  * Kernel version which takes radix argument vsnprintf(3).
567  */
568 int
569 vsnrprintf(char *str, size_t size, int radix, const char *format, va_list ap)
570 {
571 	struct snprintf_arg info;
572 	int retval;
573 
574 	info.str = str;
575 	info.remain = size;
576 	retval = kvprintf(format, snprintf_func, &info, radix, ap);
577 	if (info.remain >= 1)
578 		*info.str++ = '\0';
579 	return (retval);
580 }
581 
582 static void
583 snprintf_func(int ch, void *arg)
584 {
585 	struct snprintf_arg *const info = arg;
586 
587 	if (info->remain >= 2) {
588 		*info->str++ = ch;
589 		info->remain--;
590 	}
591 }
592 
593 /*
594  * Put a NUL-terminated ASCII number (base <= 36) in a buffer in reverse
595  * order; return an optional length and a pointer to the last character
596  * written in the buffer (i.e., the first character of the string).
597  * The buffer pointed to by `nbuf' must have length >= MAXNBUF.
598  */
599 static char *
600 ksprintn(char *nbuf, uintmax_t num, int base, int *lenp, int upper)
601 {
602 	char *p, c;
603 
604 	p = nbuf;
605 	*p = '\0';
606 	do {
607 		c = hex2ascii(num % base);
608 		*++p = upper ? toupper(c) : c;
609 	} while (num /= base);
610 	if (lenp)
611 		*lenp = p - nbuf;
612 	return (p);
613 }
614 
615 /*
616  * Scaled down version of printf(3).
617  *
618  * Two additional formats:
619  *
620  * The format %b is supported to decode error registers.
621  * Its usage is:
622  *
623  *	printf("reg=%b\n", regval, "<base><arg>*");
624  *
625  * where <base> is the output base expressed as a control character, e.g.
626  * \10 gives octal; \20 gives hex.  Each arg is a sequence of characters,
627  * the first of which gives the bit number to be inspected (origin 1), and
628  * the next characters (up to a control character, i.e. a character <= 32),
629  * give the name of the register.  Thus:
630  *
631  *	kvprintf("reg=%b\n", 3, "\10\2BITTWO\1BITONE");
632  *
633  * would produce output:
634  *
635  *	reg=3<BITTWO,BITONE>
636  *
637  * XXX:  %D  -- Hexdump, takes pointer and separator string:
638  *		("%6D", ptr, ":")   -> XX:XX:XX:XX:XX:XX
639  *		("%*D", len, ptr, " " -> XX XX XX XX ...
640  */
641 int
642 kvprintf(char const *fmt, void (*func)(int, void*), void *arg, int radix, va_list ap)
643 {
644 #define PCHAR(c) {int cc=(c); if (func) (*func)(cc,arg); else *d++ = cc; retval++; }
645 	char nbuf[MAXNBUF];
646 	char *d;
647 	const char *p, *percent, *q;
648 	u_char *up;
649 	int ch, n;
650 	uintmax_t num;
651 	int base, lflag, qflag, tmp, width, ladjust, sharpflag, neg, sign, dot;
652 	int cflag, hflag, jflag, tflag, zflag;
653 	int bconv, dwidth, upper;
654 	char padc;
655 	int stop = 0, retval = 0;
656 
657 	num = 0;
658 	if (!func)
659 		d = (char *) arg;
660 	else
661 		d = NULL;
662 
663 	if (fmt == NULL)
664 		fmt = "(fmt null)\n";
665 
666 	if (radix < 2 || radix > 36)
667 		radix = 10;
668 
669 	for (;;) {
670 		padc = ' ';
671 		width = 0;
672 		while ((ch = (u_char)*fmt++) != '%' || stop) {
673 			if (ch == '\0')
674 				return (retval);
675 			PCHAR(ch);
676 		}
677 		percent = fmt - 1;
678 		qflag = 0; lflag = 0; ladjust = 0; sharpflag = 0; neg = 0;
679 		sign = 0; dot = 0; bconv = 0; dwidth = 0; upper = 0;
680 		cflag = 0; hflag = 0; jflag = 0; tflag = 0; zflag = 0;
681 reswitch:	switch (ch = (u_char)*fmt++) {
682 		case '.':
683 			dot = 1;
684 			goto reswitch;
685 		case '#':
686 			sharpflag = 1;
687 			goto reswitch;
688 		case '+':
689 			sign = 1;
690 			goto reswitch;
691 		case '-':
692 			ladjust = 1;
693 			goto reswitch;
694 		case '%':
695 			PCHAR(ch);
696 			break;
697 		case '*':
698 			if (!dot) {
699 				width = va_arg(ap, int);
700 				if (width < 0) {
701 					ladjust = !ladjust;
702 					width = -width;
703 				}
704 			} else {
705 				dwidth = va_arg(ap, int);
706 			}
707 			goto reswitch;
708 		case '0':
709 			if (!dot) {
710 				padc = '0';
711 				goto reswitch;
712 			}
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 			if (jflag)
779 				*(va_arg(ap, intmax_t *)) = retval;
780 			else if (qflag)
781 				*(va_arg(ap, quad_t *)) = retval;
782 			else if (lflag)
783 				*(va_arg(ap, long *)) = retval;
784 			else if (zflag)
785 				*(va_arg(ap, size_t *)) = retval;
786 			else if (hflag)
787 				*(va_arg(ap, short *)) = retval;
788 			else if (cflag)
789 				*(va_arg(ap, char *)) = retval;
790 			else
791 				*(va_arg(ap, int *)) = retval;
792 			break;
793 		case 'o':
794 			base = 8;
795 			goto handle_nosign;
796 		case 'p':
797 			base = 16;
798 			sharpflag = (width == 0);
799 			sign = 0;
800 			num = (uintptr_t)va_arg(ap, void *);
801 			goto number;
802 		case 'q':
803 			qflag = 1;
804 			goto reswitch;
805 		case 'r':
806 			base = radix;
807 			if (sign)
808 				goto handle_sign;
809 			goto handle_nosign;
810 		case 's':
811 			p = va_arg(ap, char *);
812 			if (p == NULL)
813 				p = "(null)";
814 			if (!dot)
815 				n = strlen (p);
816 			else
817 				for (n = 0; n < dwidth && p[n]; n++)
818 					continue;
819 
820 			width -= n;
821 
822 			if (!ladjust && width > 0)
823 				while (width--)
824 					PCHAR(padc);
825 			while (n--)
826 				PCHAR(*p++);
827 			if (ladjust && width > 0)
828 				while (width--)
829 					PCHAR(padc);
830 			break;
831 		case 't':
832 			tflag = 1;
833 			goto reswitch;
834 		case 'u':
835 			base = 10;
836 			goto handle_nosign;
837 		case 'X':
838 			upper = 1;
839 		case 'x':
840 			base = 16;
841 			goto handle_nosign;
842 		case 'y':
843 			base = 16;
844 			sign = 1;
845 			goto handle_sign;
846 		case 'z':
847 			zflag = 1;
848 			goto reswitch;
849 handle_nosign:
850 			sign = 0;
851 			if (jflag)
852 				num = va_arg(ap, uintmax_t);
853 			else if (qflag)
854 				num = va_arg(ap, u_quad_t);
855 			else if (tflag)
856 				num = va_arg(ap, ptrdiff_t);
857 			else if (lflag)
858 				num = va_arg(ap, u_long);
859 			else if (zflag)
860 				num = va_arg(ap, size_t);
861 			else if (hflag)
862 				num = (u_short)va_arg(ap, int);
863 			else if (cflag)
864 				num = (u_char)va_arg(ap, int);
865 			else
866 				num = va_arg(ap, u_int);
867 			if (bconv) {
868 				q = va_arg(ap, char *);
869 				base = *q++;
870 			}
871 			goto number;
872 handle_sign:
873 			if (jflag)
874 				num = va_arg(ap, intmax_t);
875 			else if (qflag)
876 				num = va_arg(ap, quad_t);
877 			else if (tflag)
878 				num = va_arg(ap, ptrdiff_t);
879 			else if (lflag)
880 				num = va_arg(ap, long);
881 			else if (zflag)
882 				num = va_arg(ap, ssize_t);
883 			else if (hflag)
884 				num = (short)va_arg(ap, int);
885 			else if (cflag)
886 				num = (char)va_arg(ap, int);
887 			else
888 				num = va_arg(ap, int);
889 number:
890 			if (sign && (intmax_t)num < 0) {
891 				neg = 1;
892 				num = -(intmax_t)num;
893 			}
894 			p = ksprintn(nbuf, num, base, &n, upper);
895 			tmp = 0;
896 			if (sharpflag && num != 0) {
897 				if (base == 8)
898 					tmp++;
899 				else if (base == 16)
900 					tmp += 2;
901 			}
902 			if (neg)
903 				tmp++;
904 
905 			if (!ladjust && padc == '0')
906 				dwidth = width - tmp;
907 			width -= tmp + imax(dwidth, n);
908 			dwidth -= n;
909 			if (!ladjust)
910 				while (width-- > 0)
911 					PCHAR(' ');
912 			if (neg)
913 				PCHAR('-');
914 			if (sharpflag && num != 0) {
915 				if (base == 8) {
916 					PCHAR('0');
917 				} else if (base == 16) {
918 					PCHAR('0');
919 					PCHAR('x');
920 				}
921 			}
922 			while (dwidth-- > 0)
923 				PCHAR('0');
924 
925 			while (*p)
926 				PCHAR(*p--);
927 
928 			if (bconv && num != 0) {
929 				/* %b conversion flag format. */
930 				tmp = retval;
931 				while (*q) {
932 					n = *q++;
933 					if (num & (1 << (n - 1))) {
934 						PCHAR(retval != tmp ?
935 						    ',' : '<');
936 						for (; (n = *q) > ' '; ++q)
937 							PCHAR(n);
938 					} else
939 						for (; *q > ' '; ++q)
940 							continue;
941 				}
942 				if (retval != tmp) {
943 					PCHAR('>');
944 					width -= retval - tmp;
945 				}
946 			}
947 
948 			if (ladjust)
949 				while (width-- > 0)
950 					PCHAR(' ');
951 
952 			break;
953 		default:
954 			while (percent < fmt)
955 				PCHAR(*percent++);
956 			/*
957 			 * Since we ignore a formatting argument it is no
958 			 * longer safe to obey the remaining formatting
959 			 * arguments as the arguments will no longer match
960 			 * the format specs.
961 			 */
962 			stop = 1;
963 			break;
964 		}
965 	}
966 #undef PCHAR
967 }
968 
969 /*
970  * Put character in log buffer with a particular priority.
971  */
972 static void
973 msglogchar(int c, int pri)
974 {
975 	static int lastpri = -1;
976 	static int dangling;
977 	char nbuf[MAXNBUF];
978 	char *p;
979 
980 	if (!msgbufmapped)
981 		return;
982 	if (c == '\0' || c == '\r')
983 		return;
984 	if (pri != -1 && pri != lastpri) {
985 		if (dangling) {
986 			msgbuf_addchar(msgbufp, '\n');
987 			dangling = 0;
988 		}
989 		msgbuf_addchar(msgbufp, '<');
990 		for (p = ksprintn(nbuf, (uintmax_t)pri, 10, NULL, 0); *p;)
991 			msgbuf_addchar(msgbufp, *p--);
992 		msgbuf_addchar(msgbufp, '>');
993 		lastpri = pri;
994 	}
995 	msgbuf_addchar(msgbufp, c);
996 	if (c == '\n') {
997 		dangling = 0;
998 		lastpri = -1;
999 	} else {
1000 		dangling = 1;
1001 	}
1002 }
1003 
1004 static void
1005 msglogstr(char *str, int pri, int filter_cr)
1006 {
1007 	if (!msgbufmapped)
1008 		return;
1009 
1010 	msgbuf_addstr(msgbufp, pri, str, filter_cr);
1011 }
1012 
1013 void
1014 msgbufinit(void *ptr, int size)
1015 {
1016 	char *cp;
1017 	static struct msgbuf *oldp = NULL;
1018 
1019 	size -= sizeof(*msgbufp);
1020 	cp = (char *)ptr;
1021 	msgbufp = (struct msgbuf *)(cp + size);
1022 	msgbuf_reinit(msgbufp, cp, size);
1023 	if (msgbufmapped && oldp != msgbufp)
1024 		msgbuf_copy(oldp, msgbufp);
1025 	msgbufmapped = 1;
1026 	oldp = msgbufp;
1027 }
1028 
1029 static int unprivileged_read_msgbuf = 1;
1030 SYSCTL_INT(_security_bsd, OID_AUTO, unprivileged_read_msgbuf,
1031     CTLFLAG_RW, &unprivileged_read_msgbuf, 0,
1032     "Unprivileged processes may read the kernel message buffer");
1033 
1034 /* Sysctls for accessing/clearing the msgbuf */
1035 static int
1036 sysctl_kern_msgbuf(SYSCTL_HANDLER_ARGS)
1037 {
1038 	char buf[128];
1039 	u_int seq;
1040 	int error, len;
1041 
1042 	if (!unprivileged_read_msgbuf) {
1043 		error = priv_check(req->td, PRIV_MSGBUF);
1044 		if (error)
1045 			return (error);
1046 	}
1047 
1048 	/* Read the whole buffer, one chunk at a time. */
1049 	mtx_lock(&msgbuf_lock);
1050 	msgbuf_peekbytes(msgbufp, NULL, 0, &seq);
1051 	for (;;) {
1052 		len = msgbuf_peekbytes(msgbufp, buf, sizeof(buf), &seq);
1053 		mtx_unlock(&msgbuf_lock);
1054 		if (len == 0)
1055 			return (SYSCTL_OUT(req, "", 1)); /* add nulterm */
1056 
1057 		error = sysctl_handle_opaque(oidp, buf, len, req);
1058 		if (error)
1059 			return (error);
1060 
1061 		mtx_lock(&msgbuf_lock);
1062 	}
1063 }
1064 
1065 SYSCTL_PROC(_kern, OID_AUTO, msgbuf,
1066     CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
1067     NULL, 0, sysctl_kern_msgbuf, "A", "Contents of kernel message buffer");
1068 
1069 static int msgbuf_clearflag;
1070 
1071 static int
1072 sysctl_kern_msgbuf_clear(SYSCTL_HANDLER_ARGS)
1073 {
1074 	int error;
1075 	error = sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2, req);
1076 	if (!error && req->newptr) {
1077 		mtx_lock(&msgbuf_lock);
1078 		msgbuf_clear(msgbufp);
1079 		mtx_unlock(&msgbuf_lock);
1080 		msgbuf_clearflag = 0;
1081 	}
1082 	return (error);
1083 }
1084 
1085 SYSCTL_PROC(_kern, OID_AUTO, msgbuf_clear,
1086     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE | CTLFLAG_MPSAFE,
1087     &msgbuf_clearflag, 0, sysctl_kern_msgbuf_clear, "I",
1088     "Clear kernel message buffer");
1089 
1090 #ifdef DDB
1091 
1092 DB_SHOW_COMMAND(msgbuf, db_show_msgbuf)
1093 {
1094 	int i, j;
1095 
1096 	if (!msgbufmapped) {
1097 		db_printf("msgbuf not mapped yet\n");
1098 		return;
1099 	}
1100 	db_printf("msgbufp = %p\n", msgbufp);
1101 	db_printf("magic = %x, size = %d, r= %u, w = %u, ptr = %p, cksum= %u\n",
1102 	    msgbufp->msg_magic, msgbufp->msg_size, msgbufp->msg_rseq,
1103 	    msgbufp->msg_wseq, msgbufp->msg_ptr, msgbufp->msg_cksum);
1104 	for (i = 0; i < msgbufp->msg_size && !db_pager_quit; i++) {
1105 		j = MSGBUF_SEQ_TO_POS(msgbufp, i + msgbufp->msg_rseq);
1106 		db_printf("%c", msgbufp->msg_ptr[j]);
1107 	}
1108 	db_printf("\n");
1109 }
1110 
1111 #endif /* DDB */
1112 
1113 void
1114 hexdump(const void *ptr, int length, const char *hdr, int flags)
1115 {
1116 	int i, j, k;
1117 	int cols;
1118 	const unsigned char *cp;
1119 	char delim;
1120 
1121 	if ((flags & HD_DELIM_MASK) != 0)
1122 		delim = (flags & HD_DELIM_MASK) >> 8;
1123 	else
1124 		delim = ' ';
1125 
1126 	if ((flags & HD_COLUMN_MASK) != 0)
1127 		cols = flags & HD_COLUMN_MASK;
1128 	else
1129 		cols = 16;
1130 
1131 	cp = ptr;
1132 	for (i = 0; i < length; i+= cols) {
1133 		if (hdr != NULL)
1134 			printf("%s", hdr);
1135 
1136 		if ((flags & HD_OMIT_COUNT) == 0)
1137 			printf("%04x  ", i);
1138 
1139 		if ((flags & HD_OMIT_HEX) == 0) {
1140 			for (j = 0; j < cols; j++) {
1141 				k = i + j;
1142 				if (k < length)
1143 					printf("%c%02x", delim, cp[k]);
1144 				else
1145 					printf("   ");
1146 			}
1147 		}
1148 
1149 		if ((flags & HD_OMIT_CHARS) == 0) {
1150 			printf("  |");
1151 			for (j = 0; j < cols; j++) {
1152 				k = i + j;
1153 				if (k >= length)
1154 					printf(" ");
1155 				else if (cp[k] >= ' ' && cp[k] <= '~')
1156 					printf("%c", cp[k]);
1157 				else
1158 					printf(".");
1159 			}
1160 			printf("|");
1161 		}
1162 		printf("\n");
1163 	}
1164 }
1165 #endif /* _KERNEL */
1166 
1167 void
1168 sbuf_hexdump(struct sbuf *sb, const void *ptr, int length, const char *hdr,
1169 	     int flags)
1170 {
1171 	int i, j, k;
1172 	int cols;
1173 	const unsigned char *cp;
1174 	char delim;
1175 
1176 	if ((flags & HD_DELIM_MASK) != 0)
1177 		delim = (flags & HD_DELIM_MASK) >> 8;
1178 	else
1179 		delim = ' ';
1180 
1181 	if ((flags & HD_COLUMN_MASK) != 0)
1182 		cols = flags & HD_COLUMN_MASK;
1183 	else
1184 		cols = 16;
1185 
1186 	cp = ptr;
1187 	for (i = 0; i < length; i+= cols) {
1188 		if (hdr != NULL)
1189 			sbuf_printf(sb, "%s", hdr);
1190 
1191 		if ((flags & HD_OMIT_COUNT) == 0)
1192 			sbuf_printf(sb, "%04x  ", i);
1193 
1194 		if ((flags & HD_OMIT_HEX) == 0) {
1195 			for (j = 0; j < cols; j++) {
1196 				k = i + j;
1197 				if (k < length)
1198 					sbuf_printf(sb, "%c%02x", delim, cp[k]);
1199 				else
1200 					sbuf_printf(sb, "   ");
1201 			}
1202 		}
1203 
1204 		if ((flags & HD_OMIT_CHARS) == 0) {
1205 			sbuf_printf(sb, "  |");
1206 			for (j = 0; j < cols; j++) {
1207 				k = i + j;
1208 				if (k >= length)
1209 					sbuf_printf(sb, " ");
1210 				else if (cp[k] >= ' ' && cp[k] <= '~')
1211 					sbuf_printf(sb, "%c", cp[k]);
1212 				else
1213 					sbuf_printf(sb, ".");
1214 			}
1215 			sbuf_printf(sb, "|");
1216 		}
1217 		sbuf_printf(sb, "\n");
1218 	}
1219 }
1220 
1221 #ifdef _KERNEL
1222 void
1223 counted_warning(unsigned *counter, const char *msg)
1224 {
1225 	struct thread *td;
1226 	unsigned c;
1227 
1228 	for (;;) {
1229 		c = *counter;
1230 		if (c == 0)
1231 			break;
1232 		if (atomic_cmpset_int(counter, c, c - 1)) {
1233 			td = curthread;
1234 			log(LOG_INFO, "pid %d (%s) %s%s\n",
1235 			    td->td_proc->p_pid, td->td_name, msg,
1236 			    c > 1 ? "" : " - not logging anymore");
1237 			break;
1238 		}
1239 	}
1240 }
1241 #endif
1242 
1243 #ifdef _KERNEL
1244 void
1245 sbuf_putbuf(struct sbuf *sb)
1246 {
1247 
1248 	prf_putbuf(sbuf_data(sb), TOLOG | TOCONS, -1);
1249 }
1250 #else
1251 void
1252 sbuf_putbuf(struct sbuf *sb)
1253 {
1254 
1255 	printf("%s", sbuf_data(sb));
1256 }
1257 #endif
1258