xref: /netbsd-src/sys/kern/subr_prf.c (revision 95d875fb90b1458e4f1de6950286ddcd6644bc61)
1 /*	$NetBSD: subr_prf.c,v 1.65 1999/12/13 01:29:03 sommerfeld Exp $	*/
2 
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. All advertising materials mentioning features or use of this software
21  *    must display the following acknowledgement:
22  *	This product includes software developed by the University of
23  *	California, Berkeley and its contributors.
24  * 4. Neither the name of the University nor the names of its contributors
25  *    may be used to endorse or promote products derived from this software
26  *    without specific prior written permission.
27  *
28  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38  * SUCH DAMAGE.
39  *
40  *	@(#)subr_prf.c	8.4 (Berkeley) 5/4/95
41  */
42 
43 #include "opt_ddb.h"
44 #include "opt_multiprocessor.h"
45 #include "ipkdb.h"
46 
47 #include <sys/param.h>
48 #include <sys/systm.h>
49 #include <sys/buf.h>
50 #include <sys/conf.h>
51 #include <sys/reboot.h>
52 #include <sys/msgbuf.h>
53 #include <sys/proc.h>
54 #include <sys/ioctl.h>
55 #include <sys/vnode.h>
56 #include <sys/file.h>
57 #include <sys/tty.h>
58 #include <sys/tprintf.h>
59 #include <sys/syslog.h>
60 #include <sys/malloc.h>
61 #include <sys/lock.h>
62 
63 #include <dev/cons.h>
64 
65 #ifdef DDB
66 #include <ddb/ddbvar.h>
67 #endif
68 
69 #if defined(MULTIPROCESSOR)
70 struct simplelock kprintf_slock = SIMPLELOCK_INITIALIZER;
71 
72 /*
73  * Use cpu_simple_lock() and cpu_simple_unlock().  These are the actual
74  * atomic locking operations, and never attempt to print debugging
75  * information.
76  */
77 #define	KPRINTF_MUTEX_ENTER(s)						\
78 do {									\
79 	(s) = splhigh();						\
80 	cpu_simple_lock(&kprintf_slock);				\
81 } while (0)
82 
83 #define	KPRINTF_MUTEX_EXIT(s)						\
84 do {									\
85 	cpu_simple_unlock(&kprintf_slock);				\
86 	splx((s));							\
87 } while (0)
88 #else /* ! MULTIPROCESSOR */
89 #define	KPRINTF_MUTEX_ENTER(s)	(s) = splhigh()
90 #define	KPRINTF_MUTEX_EXIT(s)	splx((s))
91 #endif /* MULTIPROCESSOR */
92 
93 /*
94  * note that stdarg.h and the ansi style va_start macro is used for both
95  * ansi and traditional c complers.
96  * XXX: this requires that stdarg.h define: va_alist and va_dcl
97  */
98 #include <machine/stdarg.h>
99 
100 
101 #ifdef KGDB
102 #include <sys/kgdb.h>
103 #include <machine/cpu.h>
104 #endif
105 #ifdef DDB
106 #include <ddb/db_output.h>	/* db_printf, db_putchar prototypes */
107 extern	int db_radix;		/* XXX: for non-standard '%r' format */
108 #endif
109 
110 
111 /*
112  * defines
113  */
114 
115 /* flags for kprintf */
116 #define TOCONS		0x01	/* to the console */
117 #define TOTTY		0x02	/* to the process' tty */
118 #define TOLOG		0x04	/* to the kernel message buffer */
119 #define TOBUFONLY	0x08	/* to the buffer (only) [for sprintf] */
120 #define TODDB		0x10	/* to ddb console */
121 
122 /* max size buffer kprintf needs to print quad_t [size in base 8 + \0] */
123 #define KPRINTF_BUFSIZE		(sizeof(quad_t) * NBBY / 3 + 2)
124 
125 
126 /*
127  * local prototypes
128  */
129 
130 static int	 kprintf __P((const char *, int, void *,
131 				char *, va_list));
132 static void	 putchar __P((int, int, struct tty *));
133 static void	 klogpri __P((int));
134 
135 
136 /*
137  * globals
138  */
139 
140 struct	tty *constty;	/* pointer to console "window" tty */
141 int	consintr = 1;	/* ok to handle console interrupts? */
142 extern	int log_open;	/* subr_log: is /dev/klog open? */
143 const	char *panicstr; /* arg to first call to panic (used as a flag
144 			   to indicate that panic has already been called). */
145 
146 /*
147  * v_putc: routine to putc on virtual console
148  *
149  * the v_putc pointer can be used to redirect the console cnputc elsewhere
150  * [e.g. to a "virtual console"].
151  */
152 
153 void (*v_putc) __P((int)) = cnputc;	/* start with cnputc (normal cons) */
154 
155 
156 /*
157  * functions
158  */
159 
160 /*
161  * tablefull: warn that a system table is full
162  */
163 
164 void
165 tablefull(tab)
166 	const char *tab;
167 {
168 	log(LOG_ERR, "%s: table is full\n", tab);
169 }
170 
171 /*
172  * panic: handle an unresolvable fatal error
173  *
174  * prints "panic: <message>" and reboots.   if called twice (i.e. recursive
175  * call) we avoid trying to sync the disk and just reboot (to avoid
176  * recursive panics).
177  */
178 
179 void
180 #ifdef __STDC__
181 panic(const char *fmt, ...)
182 #else
183 panic(fmt, va_alist)
184 	char *fmt;
185 	va_dcl
186 #endif
187 {
188 	int bootopt;
189 	va_list ap;
190 
191 	bootopt = RB_AUTOBOOT | RB_DUMP;
192 	if (panicstr)
193 		bootopt |= RB_NOSYNC;
194 	else
195 		panicstr = fmt;
196 
197 	va_start(ap, fmt);
198 	printf("panic: ");
199 	vprintf(fmt, ap);
200 	printf("\n");
201 	va_end(ap);
202 
203 #if NIPKDB > 0
204 	ipkdb_panic();
205 #endif
206 #ifdef KGDB
207 	kgdb_panic();
208 #endif
209 #ifdef KADB
210 	if (boothowto & RB_KDB)
211 		kdbpanic();
212 #endif
213 #ifdef DDB
214 	if (db_onpanic)
215 		Debugger();
216 #endif
217 	cpu_reboot(bootopt, NULL);
218 }
219 
220 /*
221  * kernel logging functions: log, logpri, addlog
222  */
223 
224 /*
225  * log: write to the log buffer
226  *
227  * => will not sleep [so safe to call from interrupt]
228  * => will log to console if /dev/klog isn't open
229  */
230 
231 void
232 #ifdef __STDC__
233 log(int level, const char *fmt, ...)
234 #else
235 log(level, fmt, va_alist)
236 	int level;
237 	char *fmt;
238 	va_dcl
239 #endif
240 {
241 	int s;
242 	va_list ap;
243 
244 	KPRINTF_MUTEX_ENTER(s);
245 
246 	klogpri(level);		/* log the level first */
247 	va_start(ap, fmt);
248 	kprintf(fmt, TOLOG, NULL, NULL, ap);
249 	va_end(ap);
250 	if (!log_open) {
251 		va_start(ap, fmt);
252 		kprintf(fmt, TOCONS, NULL, NULL, ap);
253 		va_end(ap);
254 	}
255 
256 	KPRINTF_MUTEX_EXIT(s);
257 
258 	logwakeup();		/* wake up anyone waiting for log msgs */
259 }
260 
261 /*
262  * vlog: write to the log buffer [already have va_alist]
263  */
264 
265 void
266 vlog(level, fmt, ap)
267 	int level;
268 	const char *fmt;
269 	va_list ap;
270 {
271 	int s;
272 
273 	KPRINTF_MUTEX_ENTER(s);
274 
275 	klogpri(level);		/* log the level first */
276 	kprintf(fmt, TOLOG, NULL, NULL, ap);
277 	if (!log_open)
278 		kprintf(fmt, TOCONS, NULL, NULL, ap);
279 
280 	KPRINTF_MUTEX_EXIT(s);
281 
282 	logwakeup();		/* wake up anyone waiting for log msgs */
283 }
284 
285 /*
286  * logpri: log the priority level to the klog
287  */
288 
289 void
290 logpri(level)
291 	int level;
292 {
293 	int s;
294 
295 	KPRINTF_MUTEX_ENTER(s);
296 	klogpri(level);
297 	KPRINTF_MUTEX_EXIT(s);
298 }
299 
300 /*
301  * Note: we must be in the mutex here!
302  */
303 static void
304 klogpri(level)
305 	int level;
306 {
307 	char *p;
308 	char snbuf[KPRINTF_BUFSIZE];
309 
310 	putchar('<', TOLOG, NULL);
311 	sprintf(snbuf, "%d", level);
312 	for (p = snbuf ; *p ; p++)
313 		putchar(*p, TOLOG, NULL);
314 	putchar('>', TOLOG, NULL);
315 }
316 
317 /*
318  * addlog: add info to previous log message
319  */
320 
321 void
322 #ifdef __STDC__
323 addlog(const char *fmt, ...)
324 #else
325 addlog(fmt, va_alist)
326 	char *fmt;
327 	va_dcl
328 #endif
329 {
330 	int s;
331 	va_list ap;
332 
333 	KPRINTF_MUTEX_ENTER(s);
334 
335 	va_start(ap, fmt);
336 	kprintf(fmt, TOLOG, NULL, NULL, ap);
337 	va_end(ap);
338 	if (!log_open) {
339 		va_start(ap, fmt);
340 		kprintf(fmt, TOCONS, NULL, NULL, ap);
341 		va_end(ap);
342 	}
343 
344 	KPRINTF_MUTEX_EXIT(s);
345 
346 	logwakeup();
347 }
348 
349 
350 /*
351  * putchar: print a single character on console or user terminal.
352  *
353  * => if console, then the last MSGBUFS chars are saved in msgbuf
354  *	for inspection later (e.g. dmesg/syslog)
355  * => we must already be in the mutex!
356  */
357 static void
358 putchar(c, flags, tp)
359 	register int c;
360 	int flags;
361 	struct tty *tp;
362 {
363 	register struct kern_msgbuf *mbp;
364 
365 	if (panicstr)
366 		constty = NULL;
367 	if ((flags & TOCONS) && tp == NULL && constty) {
368 		tp = constty;
369 		flags |= TOTTY;
370 	}
371 	if ((flags & TOTTY) && tp && tputchar(c, tp) < 0 &&
372 	    (flags & TOCONS) && tp == constty)
373 		constty = NULL;
374 	if ((flags & TOLOG) &&
375 	    c != '\0' && c != '\r' && c != 0177 && msgbufenabled) {
376 		mbp = msgbufp;
377 		if (mbp->msg_magic != MSG_MAGIC) {
378 			/*
379 			 * Arguably should panic or somehow notify the
380 			 * user...  but how?  Panic may be too drastic,
381 			 * and would obliterate the message being kicked
382 			 * out (maybe a panic itself), and printf
383 			 * would invoke us recursively.  Silently punt
384 			 * for now.  If syslog is running, it should
385 			 * notice.
386 			 */
387 			msgbufenabled = 0;
388 		} else {
389 			mbp->msg_bufc[mbp->msg_bufx++] = c;
390 			if (mbp->msg_bufx < 0 || mbp->msg_bufx >= mbp->msg_bufs)
391 				mbp->msg_bufx = 0;
392 			/* If the buffer is full, keep the most recent data. */
393 			if (mbp->msg_bufr == mbp->msg_bufx) {
394 				 if (++mbp->msg_bufr >= mbp->msg_bufs)
395 					mbp->msg_bufr = 0;
396 			}
397 		}
398 	}
399 	if ((flags & TOCONS) && constty == NULL && c != '\0')
400 		(*v_putc)(c);
401 #ifdef DDB
402 	if (flags & TODDB)
403 		db_putchar(c);
404 #endif
405 }
406 
407 
408 /*
409  * uprintf: print to the controlling tty of the current process
410  *
411  * => we may block if the tty queue is full
412  * => no message is printed if the queue doesn't clear in a reasonable
413  *	time
414  */
415 
416 void
417 #ifdef __STDC__
418 uprintf(const char *fmt, ...)
419 #else
420 uprintf(fmt, va_alist)
421 	char *fmt;
422 	va_dcl
423 #endif
424 {
425 	register struct proc *p = curproc;
426 	va_list ap;
427 
428 	if (p->p_flag & P_CONTROLT && p->p_session->s_ttyvp) {
429 		/* No mutex needed; going to process TTY. */
430 		va_start(ap, fmt);
431 		kprintf(fmt, TOTTY, p->p_session->s_ttyp, NULL, ap);
432 		va_end(ap);
433 	}
434 }
435 
436 /*
437  * tprintf functions: used to send messages to a specific process
438  *
439  * usage:
440  *   get a tpr_t handle on a process "p" by using "tprintf_open(p)"
441  *   use the handle when calling "tprintf"
442  *   when done, do a "tprintf_close" to drop the handle
443  */
444 
445 /*
446  * tprintf_open: get a tprintf handle on a process "p"
447  *
448  * => returns NULL if process can't be printed to
449  */
450 
451 tpr_t
452 tprintf_open(p)
453 	register struct proc *p;
454 {
455 
456 	if (p->p_flag & P_CONTROLT && p->p_session->s_ttyvp) {
457 		SESSHOLD(p->p_session);
458 		return ((tpr_t) p->p_session);
459 	}
460 	return ((tpr_t) NULL);
461 }
462 
463 /*
464  * tprintf_close: dispose of a tprintf handle obtained with tprintf_open
465  */
466 
467 void
468 tprintf_close(sess)
469 	tpr_t sess;
470 {
471 
472 	if (sess)
473 		SESSRELE((struct session *) sess);
474 }
475 
476 /*
477  * tprintf: given tprintf handle to a process [obtained with tprintf_open],
478  * send a message to the controlling tty for that process.
479  *
480  * => also sends message to /dev/klog
481  */
482 void
483 #ifdef __STDC__
484 tprintf(tpr_t tpr, const char *fmt, ...)
485 #else
486 tprintf(tpr, fmt, va_alist)
487 	tpr_t tpr;
488 	char *fmt;
489 	va_dcl
490 #endif
491 {
492 	register struct session *sess = (struct session *)tpr;
493 	struct tty *tp = NULL;
494 	int s, flags = TOLOG;
495 	va_list ap;
496 
497 	if (sess && sess->s_ttyvp && ttycheckoutq(sess->s_ttyp, 0)) {
498 		flags |= TOTTY;
499 		tp = sess->s_ttyp;
500 	}
501 
502 	KPRINTF_MUTEX_ENTER(s);
503 
504 	klogpri(LOG_INFO);
505 	va_start(ap, fmt);
506 	kprintf(fmt, flags, tp, NULL, ap);
507 	va_end(ap);
508 
509 	KPRINTF_MUTEX_EXIT(s);
510 
511 	logwakeup();
512 }
513 
514 
515 /*
516  * ttyprintf: send a message to a specific tty
517  *
518  * => should be used only by tty driver or anything that knows the
519  *    underlying tty will not be revoked(2)'d away.  [otherwise,
520  *    use tprintf]
521  */
522 void
523 #ifdef __STDC__
524 ttyprintf(struct tty *tp, const char *fmt, ...)
525 #else
526 ttyprintf(tp, fmt, va_alist)
527 	struct tty *tp;
528 	char *fmt;
529 	va_dcl
530 #endif
531 {
532 	va_list ap;
533 
534 	/* No mutex needed; going to process TTY. */
535 	va_start(ap, fmt);
536 	kprintf(fmt, TOTTY, tp, NULL, ap);
537 	va_end(ap);
538 }
539 
540 #ifdef DDB
541 
542 /*
543  * db_printf: printf for DDB (via db_putchar)
544  */
545 
546 void
547 #ifdef __STDC__
548 db_printf(const char *fmt, ...)
549 #else
550 db_printf(fmt, va_alist)
551 	char *fmt;
552 	va_dcl
553 #endif
554 {
555 	va_list ap;
556 
557 	/* No mutex needed; DDB pauses all processors. */
558 	va_start(ap, fmt);
559 	kprintf(fmt, TODDB, NULL, NULL, ap);
560 	va_end(ap);
561 }
562 
563 #endif /* DDB */
564 
565 
566 /*
567  * normal kernel printf functions: printf, vprintf, sprintf
568  */
569 
570 /*
571  * printf: print a message to the console and the log
572  */
573 void
574 #ifdef __STDC__
575 printf(const char *fmt, ...)
576 #else
577 printf(fmt, va_alist)
578 	char *fmt;
579 	va_dcl
580 #endif
581 {
582 	va_list ap;
583 	int s, savintr;
584 
585 	KPRINTF_MUTEX_ENTER(s);
586 
587 	savintr = consintr;		/* disable interrupts */
588 	consintr = 0;
589 	va_start(ap, fmt);
590 	kprintf(fmt, TOCONS | TOLOG, NULL, NULL, ap);
591 	va_end(ap);
592 
593 	KPRINTF_MUTEX_EXIT(s);
594 
595 	if (!panicstr)
596 		logwakeup();
597 	consintr = savintr;		/* reenable interrupts */
598 }
599 
600 /*
601  * vprintf: print a message to the console and the log [already have
602  *	va_alist]
603  */
604 
605 void
606 vprintf(fmt, ap)
607 	const char *fmt;
608 	va_list ap;
609 {
610 	int s, savintr;
611 
612 	KPRINTF_MUTEX_ENTER(s);
613 
614 	savintr = consintr;		/* disable interrupts */
615 	consintr = 0;
616 	kprintf(fmt, TOCONS | TOLOG, NULL, NULL, ap);
617 
618 	KPRINTF_MUTEX_EXIT(s);
619 
620 	if (!panicstr)
621 		logwakeup();
622 	consintr = savintr;		/* reenable interrupts */
623 }
624 
625 /*
626  * sprintf: print a message to a buffer
627  */
628 int
629 #ifdef __STDC__
630 sprintf(char *buf, const char *fmt, ...)
631 #else
632 sprintf(buf, fmt, va_alist)
633         char *buf;
634         const char *cfmt;
635         va_dcl
636 #endif
637 {
638 	int retval;
639 	va_list ap;
640 
641 	va_start(ap, fmt);
642 	retval = kprintf(fmt, TOBUFONLY, NULL, buf, ap);
643 	va_end(ap);
644 	*(buf + retval) = 0;	/* null terminate */
645 	return(retval);
646 }
647 
648 /*
649  * vsprintf: print a message to a buffer [already have va_alist]
650  */
651 
652 int
653 vsprintf(buf, fmt, ap)
654 	char *buf;
655 	const char *fmt;
656 	va_list ap;
657 {
658 	int retval;
659 
660 	retval = kprintf(fmt, TOBUFONLY, NULL, buf, ap);
661 	*(buf + retval) = 0;	/* null terminate */
662 	return (retval);
663 }
664 
665 /*
666  * snprintf: print a message to a buffer
667  */
668 int
669 #ifdef __STDC__
670 snprintf(char *buf, size_t size, const char *fmt, ...)
671 #else
672 snprintf(buf, size, fmt, va_alist)
673         char *buf;
674         size_t size;
675         const char *cfmt;
676         va_dcl
677 #endif
678 {
679 	int retval;
680 	va_list ap;
681 	char *p;
682 
683 	if (size < 1)
684 		return (-1);
685 	p = buf + size - 1;
686 	va_start(ap, fmt);
687 	retval = kprintf(fmt, TOBUFONLY, &p, buf, ap);
688 	va_end(ap);
689 	*(p) = 0;	/* null terminate */
690 	return(retval);
691 }
692 
693 /*
694  * vsnprintf: print a message to a buffer [already have va_alist]
695  */
696 int
697 vsnprintf(buf, size, fmt, ap)
698         char *buf;
699         size_t size;
700         const char *fmt;
701         va_list ap;
702 {
703 	int retval;
704 	char *p;
705 
706 	if (size < 1)
707 		return (-1);
708 	p = buf + size - 1;
709 	retval = kprintf(fmt, TOBUFONLY, &p, buf, ap);
710 	*(p) = 0;	/* null terminate */
711 	return(retval);
712 }
713 
714 /*
715  * bitmask_snprintf: print a kernel-printf "%b" message to a buffer
716  *
717  * => returns pointer to the buffer
718  * => XXX: useful vs. kernel %b?
719  */
720 char *
721 bitmask_snprintf(val, p, buf, buflen)
722 	u_quad_t val;
723 	const char *p;
724 	char *buf;
725 	size_t buflen;
726 {
727 	char *bp, *q;
728 	size_t left;
729 	char *sbase, snbuf[KPRINTF_BUFSIZE];
730 	int base, bit, ch, len, sep;
731 	u_quad_t field;
732 
733 	bp = buf;
734 	memset(buf, 0, buflen);
735 
736 	/*
737 	 * Always leave room for the trailing NULL.
738 	 */
739 	left = buflen - 1;
740 
741 	/*
742 	 * Print the value into the buffer.  Abort if there's not
743 	 * enough room.
744 	 */
745 	if (buflen < KPRINTF_BUFSIZE)
746 		return (buf);
747 
748 	ch = *p++;
749 	base = ch != '\177' ? ch : *p++;
750 	sbase = base == 8 ? "%qo" : base == 10 ? "%qd" : base == 16 ? "%qx" : 0;
751 	if (sbase == 0)
752 		return (buf);	/* punt if not oct, dec, or hex */
753 
754 	sprintf(snbuf, sbase, val);
755 	for (q = snbuf ; *q ; q++) {
756 		*bp++ = *q;
757 		left--;
758 	}
759 
760 	/*
761 	 * If the value we printed was 0 and we're using the old-style format,
762 	 * or if we don't have room for "<x>", we're done.
763 	 */
764 	if (((val == 0) && (ch != '\177')) || left < 3)
765 		return (buf);
766 
767 #define PUTBYTE(b, c, l)	\
768 	*(b)++ = (c);		\
769 	if (--(l) == 0)		\
770 		goto out;
771 #define PUTSTR(b, p, l) do {		\
772 	int c;				\
773 	while ((c = *(p)++) != 0) {	\
774 		*(b)++ = c;		\
775 		if (--(l) == 0)		\
776 			goto out;	\
777 	}				\
778 } while (0)
779 
780 	/*
781 	 * Chris Torek's new style %b format is identified by a leading \177
782 	 */
783 	sep = '<';
784 	if (ch != '\177') {
785 		/* old (standard) %b format. */
786 		for (;(bit = *p++) != 0;) {
787 			if (val & (1 << (bit - 1))) {
788 				PUTBYTE(bp, sep, left);
789 				for (; (ch = *p) > ' '; ++p) {
790 					PUTBYTE(bp, ch, left);
791 				}
792 				sep = ',';
793 			} else
794 				for (; *p > ' '; ++p)
795 					continue;
796 		}
797 	} else {
798 		/* new quad-capable %b format; also does fields. */
799 		field = val;
800 		while ((ch = *p++) != '\0') {
801 			bit = *p++;	/* now 0-origin */
802 			switch (ch) {
803 			case 'b':
804 				if (((u_int)(val >> bit) & 1) == 0)
805 					goto skip;
806 				PUTBYTE(bp, sep, left);
807 				PUTSTR(bp, p, left);
808 				sep = ',';
809 				break;
810 			case 'f':
811 			case 'F':
812 				len = *p++;	/* field length */
813 				field = (val >> bit) & ((1ULL << len) - 1);
814 				if (ch == 'F')	/* just extract */
815 					break;
816 				PUTBYTE(bp, sep, left);
817 				sep = ',';
818 				PUTSTR(bp, p, left);
819 				PUTBYTE(bp, '=', left);
820 				sprintf(snbuf, sbase, field);
821 				q = snbuf; PUTSTR(bp, q, left);
822 				break;
823 			case '=':
824 			case ':':
825 				/*
826 				 * Here "bit" is actually a value instead,
827 				 * to be compared against the last field.
828 				 * This only works for values in [0..255],
829 				 * of course.
830 				 */
831 				if ((int)field != bit)
832 					goto skip;
833 				if (ch == '=')
834 					PUTBYTE(bp, '=', left);
835 				PUTSTR(bp, p, left);
836 				break;
837 			default:
838 			skip:
839 				while (*p++ != '\0')
840 					continue;
841 				break;
842 			}
843 		}
844 	}
845 	if (sep != '<')
846 		PUTBYTE(bp, '>', left);
847 
848 out:
849 	return (buf);
850 
851 #undef PUTBYTE
852 #undef PUTSTR
853 }
854 
855 /*
856  * kprintf: scaled down version of printf(3).
857  *
858  * this version based on vfprintf() from libc which was derived from
859  * software contributed to Berkeley by Chris Torek.
860  *
861  * Two additional formats:
862  *
863  * The format %b is supported to decode error registers.
864  * Its usage is:
865  *
866  *	printf("reg=%b\n", regval, "<base><arg>*");
867  *
868  * where <base> is the output base expressed as a control character, e.g.
869  * \10 gives octal; \20 gives hex.  Each arg is a sequence of characters,
870  * the first of which gives the bit number to be inspected (origin 1), and
871  * the next characters (up to a control character, i.e. a character <= 32),
872  * give the name of the register.  Thus:
873  *
874  *	kprintf("reg=%b\n", 3, "\10\2BITTWO\1BITONE\n");
875  *
876  * would produce output:
877  *
878  *	reg=3<BITTWO,BITONE>
879  *
880  * The format %: passes an additional format string and argument list
881  * recursively.  Its usage is:
882  *
883  * fn(char *fmt, ...)
884  * {
885  *	va_list ap;
886  *	va_start(ap, fmt);
887  *	printf("prefix: %: suffix\n", fmt, ap);
888  *	va_end(ap);
889  * }
890  *
891  * this is the actual printf innards
892  *
893  * This code is large and complicated...
894  *
895  * NOTE: The kprintf mutex must be held of we're going TOBUF or TOCONS!
896  */
897 
898 /*
899  * macros for converting digits to letters and vice versa
900  */
901 #define	to_digit(c)	((c) - '0')
902 #define is_digit(c)	((unsigned)to_digit(c) <= 9)
903 #define	to_char(n)	((n) + '0')
904 
905 /*
906  * flags used during conversion.
907  */
908 #define	ALT		0x001		/* alternate form */
909 #define	HEXPREFIX	0x002		/* add 0x or 0X prefix */
910 #define	LADJUST		0x004		/* left adjustment */
911 #define	LONGDBL		0x008		/* long double; unimplemented */
912 #define	LONGINT		0x010		/* long integer */
913 #define	QUADINT		0x020		/* quad integer */
914 #define	SHORTINT	0x040		/* short integer */
915 #define	ZEROPAD		0x080		/* zero (as opposed to blank) pad */
916 #define FPT		0x100		/* Floating point number */
917 
918 	/*
919 	 * To extend shorts properly, we need both signed and unsigned
920 	 * argument extraction methods.
921 	 */
922 #define	SARG() \
923 	(flags&QUADINT ? va_arg(ap, quad_t) : \
924 	    flags&LONGINT ? va_arg(ap, long) : \
925 	    flags&SHORTINT ? (long)(short)va_arg(ap, int) : \
926 	    (long)va_arg(ap, int))
927 #define	UARG() \
928 	(flags&QUADINT ? va_arg(ap, u_quad_t) : \
929 	    flags&LONGINT ? va_arg(ap, u_long) : \
930 	    flags&SHORTINT ? (u_long)(u_short)va_arg(ap, int) : \
931 	    (u_long)va_arg(ap, u_int))
932 
933 #define KPRINTF_PUTCHAR(C) {						\
934 	if (oflags == TOBUFONLY) {					\
935 		if ((vp != NULL) && (sbuf == tailp)) {			\
936 			ret += 1;		/* indicate error */	\
937 			goto overflow;					\
938 		}							\
939 		*sbuf++ = (C);						\
940 	} else {							\
941 		putchar((C), oflags, (struct tty *)vp);			\
942 	}								\
943 }
944 
945 /*
946  * Guts of kernel printf.  Note, we already expect to be in a mutex!
947  */
948 static int
949 kprintf(fmt0, oflags, vp, sbuf, ap)
950 	const char *fmt0;
951 	int oflags;
952 	void *vp;
953 	char *sbuf;
954 	va_list ap;
955 {
956 	char *fmt;		/* format string */
957 	int ch;			/* character from fmt */
958 	int n;			/* handy integer (short term usage) */
959 	char *cp;		/* handy char pointer (short term usage) */
960 	int flags;		/* flags as above */
961 	int ret;		/* return value accumulator */
962 	int width;		/* width from format (%8d), or 0 */
963 	int prec;		/* precision from format (%.3d), or -1 */
964 	char sign;		/* sign prefix (' ', '+', '-', or \0) */
965 
966 	u_quad_t _uquad;	/* integer arguments %[diouxX] */
967 	enum { OCT, DEC, HEX } base;/* base for [diouxX] conversion */
968 	int dprec;		/* a copy of prec if [diouxX], 0 otherwise */
969 	int realsz;		/* field size expanded by dprec */
970 	int size;		/* size of converted field or string */
971 	char *xdigs;		/* digits for [xX] conversion */
972 	char buf[KPRINTF_BUFSIZE]; /* space for %c, %[diouxX] */
973 	char *tailp;		/* tail pointer for snprintf */
974 
975 	tailp = NULL;	/* XXX: shutup gcc */
976 	if (oflags == TOBUFONLY && (vp != NULL))
977 		tailp = *(char **)vp;
978 
979 	cp = NULL;	/* XXX: shutup gcc */
980 	size = 0;	/* XXX: shutup gcc */
981 
982 	fmt = (char *)fmt0;
983 	ret = 0;
984 
985 	xdigs = NULL;		/* XXX: shut up gcc warning */
986 
987 	/*
988 	 * Scan the format for conversions (`%' character).
989 	 */
990 	for (;;) {
991 		while (*fmt != '%' && *fmt) {
992 			ret++;
993 			KPRINTF_PUTCHAR(*fmt++);
994 		}
995 		if (*fmt == 0)
996 			goto done;
997 
998 		fmt++;		/* skip over '%' */
999 
1000 		flags = 0;
1001 		dprec = 0;
1002 		width = 0;
1003 		prec = -1;
1004 		sign = '\0';
1005 
1006 rflag:		ch = *fmt++;
1007 reswitch:	switch (ch) {
1008 		/* XXX: non-standard '%:' format */
1009 #ifndef __powerpc__
1010 		case ':':
1011 			if (oflags != TOBUFONLY) {
1012 				cp = va_arg(ap, char *);
1013 				kprintf(cp, oflags, vp,
1014 					NULL, va_arg(ap, va_list));
1015 			}
1016 			continue;	/* no output */
1017 #endif
1018 		/* XXX: non-standard '%b' format */
1019 		case 'b': {
1020 			char *b, *z;
1021 			int tmp;
1022 			_uquad = va_arg(ap, int);
1023 			b = va_arg(ap, char *);
1024 			if (*b == 8)
1025 				sprintf(buf, "%qo", (unsigned long long)_uquad);
1026 			else if (*b == 10)
1027 				sprintf(buf, "%qd", (unsigned long long)_uquad);
1028 			else if (*b == 16)
1029 				sprintf(buf, "%qx", (unsigned long long)_uquad);
1030 			else
1031 				break;
1032 			b++;
1033 
1034 			z = buf;
1035 			while (*z) {
1036 				ret++;
1037 				KPRINTF_PUTCHAR(*z++);
1038 			}
1039 
1040 			if (_uquad) {
1041 				tmp = 0;
1042 				while ((n = *b++) != 0) {
1043 					if (_uquad & (1 << (n - 1))) {
1044 						ret++;
1045 						KPRINTF_PUTCHAR(tmp ? ',':'<');
1046 						while ((n = *b) > ' ') {
1047 							ret++;
1048 							KPRINTF_PUTCHAR(n);
1049 							b++;
1050 						}
1051 						tmp = 1;
1052 					} else {
1053 						while(*b > ' ')
1054 							b++;
1055 					}
1056 				}
1057 				if (tmp) {
1058 					ret++;
1059 					KPRINTF_PUTCHAR('>');
1060 				}
1061 			}
1062 			continue;	/* no output */
1063 		}
1064 
1065 #ifdef DDB
1066 		/* XXX: non-standard '%r' format (print int in db_radix) */
1067 		case 'r':
1068 			if ((oflags & TODDB) == 0)
1069 				goto default_case;
1070 
1071 			if (db_radix == 16)
1072 				goto case_z;	/* signed hex */
1073 			_uquad = SARG();
1074 			if ((quad_t)_uquad < 0) {
1075 				_uquad = -_uquad;
1076 				sign = '-';
1077 			}
1078 			base = (db_radix == 8) ? OCT : DEC;
1079 			goto number;
1080 
1081 
1082 		/* XXX: non-standard '%z' format ("signed hex", a "hex %i")*/
1083 		case 'z':
1084 		case_z:
1085 			if ((oflags & TODDB) == 0)
1086 				goto default_case;
1087 
1088 			xdigs = "0123456789abcdef";
1089 			ch = 'x';	/* the 'x' in '0x' (below) */
1090 			_uquad = SARG();
1091 			base = HEX;
1092 			/* leading 0x/X only if non-zero */
1093 			if (flags & ALT && _uquad != 0)
1094 				flags |= HEXPREFIX;
1095 			if ((quad_t)_uquad < 0) {
1096 				_uquad = -_uquad;
1097 				sign = '-';
1098 			}
1099 			goto number;
1100 #endif
1101 
1102 		case ' ':
1103 			/*
1104 			 * ``If the space and + flags both appear, the space
1105 			 * flag will be ignored.''
1106 			 *	-- ANSI X3J11
1107 			 */
1108 			if (!sign)
1109 				sign = ' ';
1110 			goto rflag;
1111 		case '#':
1112 			flags |= ALT;
1113 			goto rflag;
1114 		case '*':
1115 			/*
1116 			 * ``A negative field width argument is taken as a
1117 			 * - flag followed by a positive field width.''
1118 			 *	-- ANSI X3J11
1119 			 * They don't exclude field widths read from args.
1120 			 */
1121 			if ((width = va_arg(ap, int)) >= 0)
1122 				goto rflag;
1123 			width = -width;
1124 			/* FALLTHROUGH */
1125 		case '-':
1126 			flags |= LADJUST;
1127 			goto rflag;
1128 		case '+':
1129 			sign = '+';
1130 			goto rflag;
1131 		case '.':
1132 			if ((ch = *fmt++) == '*') {
1133 				n = va_arg(ap, int);
1134 				prec = n < 0 ? -1 : n;
1135 				goto rflag;
1136 			}
1137 			n = 0;
1138 			while (is_digit(ch)) {
1139 				n = 10 * n + to_digit(ch);
1140 				ch = *fmt++;
1141 			}
1142 			prec = n < 0 ? -1 : n;
1143 			goto reswitch;
1144 		case '0':
1145 			/*
1146 			 * ``Note that 0 is taken as a flag, not as the
1147 			 * beginning of a field width.''
1148 			 *	-- ANSI X3J11
1149 			 */
1150 			flags |= ZEROPAD;
1151 			goto rflag;
1152 		case '1': case '2': case '3': case '4':
1153 		case '5': case '6': case '7': case '8': case '9':
1154 			n = 0;
1155 			do {
1156 				n = 10 * n + to_digit(ch);
1157 				ch = *fmt++;
1158 			} while (is_digit(ch));
1159 			width = n;
1160 			goto reswitch;
1161 		case 'h':
1162 			flags |= SHORTINT;
1163 			goto rflag;
1164 		case 'l':
1165 			if (*fmt == 'l') {
1166 				fmt++;
1167 				flags |= QUADINT;
1168 			} else {
1169 				flags |= LONGINT;
1170 			}
1171 			goto rflag;
1172 		case 'q':
1173 			flags |= QUADINT;
1174 			goto rflag;
1175 		case 'c':
1176 			*(cp = buf) = va_arg(ap, int);
1177 			size = 1;
1178 			sign = '\0';
1179 			break;
1180 		case 'D':
1181 			flags |= LONGINT;
1182 			/*FALLTHROUGH*/
1183 		case 'd':
1184 		case 'i':
1185 			_uquad = SARG();
1186 			if ((quad_t)_uquad < 0) {
1187 				_uquad = -_uquad;
1188 				sign = '-';
1189 			}
1190 			base = DEC;
1191 			goto number;
1192 		case 'n':
1193 #ifdef DDB
1194 		/* XXX: non-standard '%n' format */
1195 		/*
1196 		 * XXX: HACK!   DDB wants '%n' to be a '%u' printed
1197 		 * in db_radix format.   this should die since '%n'
1198 		 * is already defined in standard printf to write
1199 		 * the number of chars printed so far to the arg (which
1200 		 * should be a pointer.
1201 		 */
1202 			if (oflags & TODDB) {
1203 				if (db_radix == 16)
1204 					ch = 'x';	/* convert to %x */
1205 				else if (db_radix == 8)
1206 					ch = 'o';	/* convert to %o */
1207 				else
1208 					ch = 'u';	/* convert to %u */
1209 
1210 				/* ... and start again */
1211 				goto reswitch;
1212 			}
1213 
1214 #endif
1215 			if (flags & QUADINT)
1216 				*va_arg(ap, quad_t *) = ret;
1217 			else if (flags & LONGINT)
1218 				*va_arg(ap, long *) = ret;
1219 			else if (flags & SHORTINT)
1220 				*va_arg(ap, short *) = ret;
1221 			else
1222 				*va_arg(ap, int *) = ret;
1223 			continue;	/* no output */
1224 		case 'O':
1225 			flags |= LONGINT;
1226 			/*FALLTHROUGH*/
1227 		case 'o':
1228 			_uquad = UARG();
1229 			base = OCT;
1230 			goto nosign;
1231 		case 'p':
1232 			/*
1233 			 * ``The argument shall be a pointer to void.  The
1234 			 * value of the pointer is converted to a sequence
1235 			 * of printable characters, in an implementation-
1236 			 * defined manner.''
1237 			 *	-- ANSI X3J11
1238 			 */
1239 			/* NOSTRICT */
1240 			_uquad = (u_long)va_arg(ap, void *);
1241 			base = HEX;
1242 			xdigs = "0123456789abcdef";
1243 			flags |= HEXPREFIX;
1244 			ch = 'x';
1245 			goto nosign;
1246 		case 's':
1247 			if ((cp = va_arg(ap, char *)) == NULL)
1248 				cp = "(null)";
1249 			if (prec >= 0) {
1250 				/*
1251 				 * can't use strlen; can only look for the
1252 				 * NUL in the first `prec' characters, and
1253 				 * strlen() will go further.
1254 				 */
1255 				char *p = memchr(cp, 0, prec);
1256 
1257 				if (p != NULL) {
1258 					size = p - cp;
1259 					if (size > prec)
1260 						size = prec;
1261 				} else
1262 					size = prec;
1263 			} else
1264 				size = strlen(cp);
1265 			sign = '\0';
1266 			break;
1267 		case 'U':
1268 			flags |= LONGINT;
1269 			/*FALLTHROUGH*/
1270 		case 'u':
1271 			_uquad = UARG();
1272 			base = DEC;
1273 			goto nosign;
1274 		case 'X':
1275 			xdigs = "0123456789ABCDEF";
1276 			goto hex;
1277 		case 'x':
1278 			xdigs = "0123456789abcdef";
1279 hex:			_uquad = UARG();
1280 			base = HEX;
1281 			/* leading 0x/X only if non-zero */
1282 			if (flags & ALT && _uquad != 0)
1283 				flags |= HEXPREFIX;
1284 
1285 			/* unsigned conversions */
1286 nosign:			sign = '\0';
1287 			/*
1288 			 * ``... diouXx conversions ... if a precision is
1289 			 * specified, the 0 flag will be ignored.''
1290 			 *	-- ANSI X3J11
1291 			 */
1292 number:			if ((dprec = prec) >= 0)
1293 				flags &= ~ZEROPAD;
1294 
1295 			/*
1296 			 * ``The result of converting a zero value with an
1297 			 * explicit precision of zero is no characters.''
1298 			 *	-- ANSI X3J11
1299 			 */
1300 			cp = buf + KPRINTF_BUFSIZE;
1301 			if (_uquad != 0 || prec != 0) {
1302 				/*
1303 				 * Unsigned mod is hard, and unsigned mod
1304 				 * by a constant is easier than that by
1305 				 * a variable; hence this switch.
1306 				 */
1307 				switch (base) {
1308 				case OCT:
1309 					do {
1310 						*--cp = to_char(_uquad & 7);
1311 						_uquad >>= 3;
1312 					} while (_uquad);
1313 					/* handle octal leading 0 */
1314 					if (flags & ALT && *cp != '0')
1315 						*--cp = '0';
1316 					break;
1317 
1318 				case DEC:
1319 					/* many numbers are 1 digit */
1320 					while (_uquad >= 10) {
1321 						*--cp = to_char(_uquad % 10);
1322 						_uquad /= 10;
1323 					}
1324 					*--cp = to_char(_uquad);
1325 					break;
1326 
1327 				case HEX:
1328 					do {
1329 						*--cp = xdigs[_uquad & 15];
1330 						_uquad >>= 4;
1331 					} while (_uquad);
1332 					break;
1333 
1334 				default:
1335 					cp = "bug in kprintf: bad base";
1336 					size = strlen(cp);
1337 					goto skipsize;
1338 				}
1339 			}
1340 			size = buf + KPRINTF_BUFSIZE - cp;
1341 		skipsize:
1342 			break;
1343 		default:	/* "%?" prints ?, unless ? is NUL */
1344 #ifdef DDB
1345 		default_case:	/* DDB */
1346 #endif
1347 			if (ch == '\0')
1348 				goto done;
1349 			/* pretend it was %c with argument ch */
1350 			cp = buf;
1351 			*cp = ch;
1352 			size = 1;
1353 			sign = '\0';
1354 			break;
1355 		}
1356 
1357 		/*
1358 		 * All reasonable formats wind up here.  At this point, `cp'
1359 		 * points to a string which (if not flags&LADJUST) should be
1360 		 * padded out to `width' places.  If flags&ZEROPAD, it should
1361 		 * first be prefixed by any sign or other prefix; otherwise,
1362 		 * it should be blank padded before the prefix is emitted.
1363 		 * After any left-hand padding and prefixing, emit zeroes
1364 		 * required by a decimal [diouxX] precision, then print the
1365 		 * string proper, then emit zeroes required by any leftover
1366 		 * floating precision; finally, if LADJUST, pad with blanks.
1367 		 *
1368 		 * Compute actual size, so we know how much to pad.
1369 		 * size excludes decimal prec; realsz includes it.
1370 		 */
1371 		realsz = dprec > size ? dprec : size;
1372 		if (sign)
1373 			realsz++;
1374 		else if (flags & HEXPREFIX)
1375 			realsz+= 2;
1376 
1377 		/* adjust ret */
1378 		ret += width > realsz ? width : realsz;
1379 
1380 		/* right-adjusting blank padding */
1381 		if ((flags & (LADJUST|ZEROPAD)) == 0) {
1382 			n = width - realsz;
1383 			while (n-- > 0)
1384 				KPRINTF_PUTCHAR(' ');
1385 		}
1386 
1387 		/* prefix */
1388 		if (sign) {
1389 			KPRINTF_PUTCHAR(sign);
1390 		} else if (flags & HEXPREFIX) {
1391 			KPRINTF_PUTCHAR('0');
1392 			KPRINTF_PUTCHAR(ch);
1393 		}
1394 
1395 		/* right-adjusting zero padding */
1396 		if ((flags & (LADJUST|ZEROPAD)) == ZEROPAD) {
1397 			n = width - realsz;
1398 			while (n-- > 0)
1399 				KPRINTF_PUTCHAR('0');
1400 		}
1401 
1402 		/* leading zeroes from decimal precision */
1403 		n = dprec - size;
1404 		while (n-- > 0)
1405 			KPRINTF_PUTCHAR('0');
1406 
1407 		/* the string or number proper */
1408 		while (size--)
1409 			KPRINTF_PUTCHAR(*cp++);
1410 		/* left-adjusting padding (always blank) */
1411 		if (flags & LADJUST) {
1412 			n = width - realsz;
1413 			while (n-- > 0)
1414 				KPRINTF_PUTCHAR(' ');
1415 		}
1416 	}
1417 
1418 done:
1419 	if ((oflags == TOBUFONLY) && (vp != NULL))
1420 		*(char **)vp = sbuf;
1421 overflow:
1422 	return (ret);
1423 	/* NOTREACHED */
1424 }
1425