xref: /netbsd-src/sys/kern/subr_prf.c (revision 27578b9aac214cc7796ead81dcc5427e79d5f2a0)
1 /*	$NetBSD: subr_prf.c,v 1.81 2001/07/10 20:40:56 fvdl 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_ipkdb.h"
45 #include "opt_kgdb.h"
46 #include "opt_multiprocessor.h"
47 
48 #include <sys/param.h>
49 #include <sys/stdint.h>
50 #include <sys/systm.h>
51 #include <sys/buf.h>
52 #include <sys/reboot.h>
53 #include <sys/msgbuf.h>
54 #include <sys/proc.h>
55 #include <sys/ioctl.h>
56 #include <sys/vnode.h>
57 #include <sys/file.h>
58 #include <sys/tty.h>
59 #include <sys/tprintf.h>
60 #include <sys/syslog.h>
61 #include <sys/malloc.h>
62 #include <sys/lock.h>
63 
64 #include <dev/cons.h>
65 
66 #ifdef DDB
67 #include <ddb/ddbvar.h>
68 #include <machine/db_machdep.h>
69 #include <ddb/db_command.h>
70 #include <ddb/db_interface.h>
71 #endif
72 
73 #ifdef IPKDB
74 #include <ipkdb/ipkdb.h>
75 #endif
76 
77 #if defined(MULTIPROCESSOR)
78 struct simplelock kprintf_slock = SIMPLELOCK_INITIALIZER;
79 
80 /*
81  * Use cpu_simple_lock() and cpu_simple_unlock().  These are the actual
82  * atomic locking operations, and never attempt to print debugging
83  * information.
84  */
85 #define	KPRINTF_MUTEX_ENTER(s)						\
86 do {									\
87 	(s) = splhigh();						\
88 	__cpu_simple_lock(&kprintf_slock.lock_data);			\
89 } while (0)
90 
91 #define	KPRINTF_MUTEX_EXIT(s)						\
92 do {									\
93 	__cpu_simple_unlock(&kprintf_slock.lock_data);			\
94 	splx((s));							\
95 } while (0)
96 #else /* ! MULTIPROCESSOR */
97 #define	KPRINTF_MUTEX_ENTER(s)	(s) = splhigh()
98 #define	KPRINTF_MUTEX_EXIT(s)	splx((s))
99 #endif /* MULTIPROCESSOR */
100 
101 /*
102  * note that stdarg.h and the ansi style va_start macro is used for both
103  * ansi and traditional c complers.
104  * XXX: this requires that stdarg.h define: va_alist and va_dcl
105  */
106 #include <machine/stdarg.h>
107 
108 
109 #ifdef KGDB
110 #include <sys/kgdb.h>
111 #include <machine/cpu.h>
112 #endif
113 #ifdef DDB
114 #include <ddb/db_output.h>	/* db_printf, db_putchar prototypes */
115 #endif
116 
117 
118 /*
119  * defines
120  */
121 
122 /* flags for kprintf */
123 #define TOCONS		0x01	/* to the console */
124 #define TOTTY		0x02	/* to the process' tty */
125 #define TOLOG		0x04	/* to the kernel message buffer */
126 #define TOBUFONLY	0x08	/* to the buffer (only) [for snprintf] */
127 #define TODDB		0x10	/* to ddb console */
128 
129 /* max size buffer kprintf needs to print quad_t [size in base 8 + \0] */
130 #define KPRINTF_BUFSIZE		(sizeof(quad_t) * NBBY / 3 + 2)
131 
132 
133 /*
134  * local prototypes
135  */
136 
137 static int	 kprintf __P((const char *, int, void *,
138 				char *, va_list));
139 static void	 putchar __P((int, int, struct tty *));
140 static void	 klogpri __P((int));
141 
142 
143 /*
144  * globals
145  */
146 
147 extern	struct tty *constty;	/* pointer to console "window" tty */
148 extern	int log_open;	/* subr_log: is /dev/klog open? */
149 const	char *panicstr; /* arg to first call to panic (used as a flag
150 			   to indicate that panic has already been called). */
151 long	panicstart, panicend;	/* position in the msgbuf of the start and
152 				   end of the formatted panicstr. */
153 int	doing_shutdown;	/* set to indicate shutdown in progress */
154 
155 /*
156  * v_putc: routine to putc on virtual console
157  *
158  * the v_putc pointer can be used to redirect the console cnputc elsewhere
159  * [e.g. to a "virtual console"].
160  */
161 
162 void (*v_putc) __P((int)) = cnputc;	/* start with cnputc (normal cons) */
163 
164 
165 /*
166  * functions
167  */
168 
169 /*
170  * tablefull: warn that a system table is full
171  */
172 
173 void
174 tablefull(tab, hint)
175 	const char *tab, *hint;
176 {
177 	if (hint)
178 		log(LOG_ERR, "%s: table is full - %s\n", tab, hint);
179 	else
180 		log(LOG_ERR, "%s: table is full\n", tab);
181 }
182 
183 /*
184  * panic: handle an unresolvable fatal error
185  *
186  * prints "panic: <message>" and reboots.   if called twice (i.e. recursive
187  * call) we avoid trying to sync the disk and just reboot (to avoid
188  * recursive panics).
189  */
190 
191 void
192 #ifdef __STDC__
193 panic(const char *fmt, ...)
194 #else
195 panic(fmt, va_alist)
196 	char *fmt;
197 	va_dcl
198 #endif
199 {
200 	int bootopt;
201 	va_list ap;
202 
203 	bootopt = RB_AUTOBOOT | RB_DUMP;
204 	if (doing_shutdown)
205 		bootopt |= RB_NOSYNC;
206 	if (!panicstr)
207 		panicstr = fmt;
208 	doing_shutdown = 1;
209 
210 	if (msgbufenabled && msgbufp->msg_magic == MSG_MAGIC)
211 		panicstart = msgbufp->msg_bufx;
212 
213 	va_start(ap, fmt);
214 	printf("panic: ");
215 	vprintf(fmt, ap);
216 	printf("\n");
217 	va_end(ap);
218 
219 	if (msgbufenabled && msgbufp->msg_magic == MSG_MAGIC)
220 		panicend = msgbufp->msg_bufx;
221 
222 #ifdef IPKDB
223 	ipkdb_panic();
224 #endif
225 #ifdef KGDB
226 	kgdb_panic();
227 #endif
228 #ifdef KADB
229 	if (boothowto & RB_KDB)
230 		kdbpanic();
231 #endif
232 #ifdef DDB
233 	if (db_onpanic)
234 		Debugger();
235 	else {
236 		static int intrace = 0;
237 
238 		if (intrace==0) {
239 			intrace=1;
240 			printf("Begin traceback...\n");
241 			db_stack_trace_print(
242 			    (db_expr_t)__builtin_frame_address(0),
243 			    TRUE, 65535, "", printf);
244 			printf("End traceback...\n");
245 			intrace=0;
246 		} else
247 			printf("Faulted in mid-traceback; aborting...");
248 	}
249 #endif
250 	cpu_reboot(bootopt, NULL);
251 }
252 
253 /*
254  * kernel logging functions: log, logpri, addlog
255  */
256 
257 /*
258  * log: write to the log buffer
259  *
260  * => will not sleep [so safe to call from interrupt]
261  * => will log to console if /dev/klog isn't open
262  */
263 
264 void
265 #ifdef __STDC__
266 log(int level, const char *fmt, ...)
267 #else
268 log(level, fmt, va_alist)
269 	int level;
270 	char *fmt;
271 	va_dcl
272 #endif
273 {
274 	int s;
275 	va_list ap;
276 
277 	KPRINTF_MUTEX_ENTER(s);
278 
279 	klogpri(level);		/* log the level first */
280 	va_start(ap, fmt);
281 	kprintf(fmt, TOLOG, NULL, NULL, ap);
282 	va_end(ap);
283 	if (!log_open) {
284 		va_start(ap, fmt);
285 		kprintf(fmt, TOCONS, NULL, NULL, ap);
286 		va_end(ap);
287 	}
288 
289 	KPRINTF_MUTEX_EXIT(s);
290 
291 	logwakeup();		/* wake up anyone waiting for log msgs */
292 }
293 
294 /*
295  * vlog: write to the log buffer [already have va_alist]
296  */
297 
298 void
299 vlog(level, fmt, ap)
300 	int level;
301 	const char *fmt;
302 	va_list ap;
303 {
304 	int s;
305 
306 	KPRINTF_MUTEX_ENTER(s);
307 
308 	klogpri(level);		/* log the level first */
309 	kprintf(fmt, TOLOG, NULL, NULL, ap);
310 	if (!log_open)
311 		kprintf(fmt, TOCONS, NULL, NULL, ap);
312 
313 	KPRINTF_MUTEX_EXIT(s);
314 
315 	logwakeup();		/* wake up anyone waiting for log msgs */
316 }
317 
318 /*
319  * logpri: log the priority level to the klog
320  */
321 
322 void
323 logpri(level)
324 	int level;
325 {
326 	int s;
327 
328 	KPRINTF_MUTEX_ENTER(s);
329 	klogpri(level);
330 	KPRINTF_MUTEX_EXIT(s);
331 }
332 
333 /*
334  * Note: we must be in the mutex here!
335  */
336 static void
337 klogpri(level)
338 	int level;
339 {
340 	char *p;
341 	char snbuf[KPRINTF_BUFSIZE];
342 
343 	putchar('<', TOLOG, NULL);
344 	snprintf(snbuf, sizeof(snbuf), "%d", level);
345 	for (p = snbuf ; *p ; p++)
346 		putchar(*p, TOLOG, NULL);
347 	putchar('>', TOLOG, NULL);
348 }
349 
350 /*
351  * addlog: add info to previous log message
352  */
353 
354 void
355 #ifdef __STDC__
356 addlog(const char *fmt, ...)
357 #else
358 addlog(fmt, va_alist)
359 	char *fmt;
360 	va_dcl
361 #endif
362 {
363 	int s;
364 	va_list ap;
365 
366 	KPRINTF_MUTEX_ENTER(s);
367 
368 	va_start(ap, fmt);
369 	kprintf(fmt, TOLOG, NULL, NULL, ap);
370 	va_end(ap);
371 	if (!log_open) {
372 		va_start(ap, fmt);
373 		kprintf(fmt, TOCONS, NULL, NULL, ap);
374 		va_end(ap);
375 	}
376 
377 	KPRINTF_MUTEX_EXIT(s);
378 
379 	logwakeup();
380 }
381 
382 
383 /*
384  * putchar: print a single character on console or user terminal.
385  *
386  * => if console, then the last MSGBUFS chars are saved in msgbuf
387  *	for inspection later (e.g. dmesg/syslog)
388  * => we must already be in the mutex!
389  */
390 static void
391 putchar(c, flags, tp)
392 	int c;
393 	int flags;
394 	struct tty *tp;
395 {
396 	struct kern_msgbuf *mbp;
397 
398 	if (panicstr)
399 		constty = NULL;
400 	if ((flags & TOCONS) && tp == NULL && constty) {
401 		tp = constty;
402 		flags |= TOTTY;
403 	}
404 	if ((flags & TOTTY) && tp && tputchar(c, tp) < 0 &&
405 	    (flags & TOCONS) && tp == constty)
406 		constty = NULL;
407 	if ((flags & TOLOG) &&
408 	    c != '\0' && c != '\r' && c != 0177 && msgbufenabled) {
409 		mbp = msgbufp;
410 		if (mbp->msg_magic != MSG_MAGIC) {
411 			/*
412 			 * Arguably should panic or somehow notify the
413 			 * user...  but how?  Panic may be too drastic,
414 			 * and would obliterate the message being kicked
415 			 * out (maybe a panic itself), and printf
416 			 * would invoke us recursively.  Silently punt
417 			 * for now.  If syslog is running, it should
418 			 * notice.
419 			 */
420 			msgbufenabled = 0;
421 		} else {
422 			mbp->msg_bufc[mbp->msg_bufx++] = c;
423 			if (mbp->msg_bufx < 0 || mbp->msg_bufx >= mbp->msg_bufs)
424 				mbp->msg_bufx = 0;
425 			/* If the buffer is full, keep the most recent data. */
426 			if (mbp->msg_bufr == mbp->msg_bufx) {
427 				 if (++mbp->msg_bufr >= mbp->msg_bufs)
428 					mbp->msg_bufr = 0;
429 			}
430 		}
431 	}
432 	if ((flags & TOCONS) && constty == NULL && c != '\0')
433 		(*v_putc)(c);
434 #ifdef DDB
435 	if (flags & TODDB)
436 		db_putchar(c);
437 #endif
438 }
439 
440 
441 /*
442  * uprintf: print to the controlling tty of the current process
443  *
444  * => we may block if the tty queue is full
445  * => no message is printed if the queue doesn't clear in a reasonable
446  *	time
447  */
448 
449 void
450 #ifdef __STDC__
451 uprintf(const char *fmt, ...)
452 #else
453 uprintf(fmt, va_alist)
454 	char *fmt;
455 	va_dcl
456 #endif
457 {
458 	struct proc *p = curproc;
459 	va_list ap;
460 
461 	if (p->p_flag & P_CONTROLT && p->p_session->s_ttyvp) {
462 		/* No mutex needed; going to process TTY. */
463 		va_start(ap, fmt);
464 		kprintf(fmt, TOTTY, p->p_session->s_ttyp, NULL, ap);
465 		va_end(ap);
466 	}
467 }
468 
469 /*
470  * tprintf functions: used to send messages to a specific process
471  *
472  * usage:
473  *   get a tpr_t handle on a process "p" by using "tprintf_open(p)"
474  *   use the handle when calling "tprintf"
475  *   when done, do a "tprintf_close" to drop the handle
476  */
477 
478 /*
479  * tprintf_open: get a tprintf handle on a process "p"
480  *
481  * => returns NULL if process can't be printed to
482  */
483 
484 tpr_t
485 tprintf_open(p)
486 	struct proc *p;
487 {
488 
489 	if (p->p_flag & P_CONTROLT && p->p_session->s_ttyvp) {
490 		SESSHOLD(p->p_session);
491 		return ((tpr_t) p->p_session);
492 	}
493 	return ((tpr_t) NULL);
494 }
495 
496 /*
497  * tprintf_close: dispose of a tprintf handle obtained with tprintf_open
498  */
499 
500 void
501 tprintf_close(sess)
502 	tpr_t sess;
503 {
504 
505 	if (sess)
506 		SESSRELE((struct session *) sess);
507 }
508 
509 /*
510  * tprintf: given tprintf handle to a process [obtained with tprintf_open],
511  * send a message to the controlling tty for that process.
512  *
513  * => also sends message to /dev/klog
514  */
515 void
516 #ifdef __STDC__
517 tprintf(tpr_t tpr, const char *fmt, ...)
518 #else
519 tprintf(tpr, fmt, va_alist)
520 	tpr_t tpr;
521 	char *fmt;
522 	va_dcl
523 #endif
524 {
525 	struct session *sess = (struct session *)tpr;
526 	struct tty *tp = NULL;
527 	int s, flags = TOLOG;
528 	va_list ap;
529 
530 	if (sess && sess->s_ttyvp && ttycheckoutq(sess->s_ttyp, 0)) {
531 		flags |= TOTTY;
532 		tp = sess->s_ttyp;
533 	}
534 
535 	KPRINTF_MUTEX_ENTER(s);
536 
537 	klogpri(LOG_INFO);
538 	va_start(ap, fmt);
539 	kprintf(fmt, flags, tp, NULL, ap);
540 	va_end(ap);
541 
542 	KPRINTF_MUTEX_EXIT(s);
543 
544 	logwakeup();
545 }
546 
547 
548 /*
549  * ttyprintf: send a message to a specific tty
550  *
551  * => should be used only by tty driver or anything that knows the
552  *    underlying tty will not be revoked(2)'d away.  [otherwise,
553  *    use tprintf]
554  */
555 void
556 #ifdef __STDC__
557 ttyprintf(struct tty *tp, const char *fmt, ...)
558 #else
559 ttyprintf(tp, fmt, va_alist)
560 	struct tty *tp;
561 	char *fmt;
562 	va_dcl
563 #endif
564 {
565 	va_list ap;
566 
567 	/* No mutex needed; going to process TTY. */
568 	va_start(ap, fmt);
569 	kprintf(fmt, TOTTY, tp, NULL, ap);
570 	va_end(ap);
571 }
572 
573 #ifdef DDB
574 
575 /*
576  * db_printf: printf for DDB (via db_putchar)
577  */
578 
579 void
580 #ifdef __STDC__
581 db_printf(const char *fmt, ...)
582 #else
583 db_printf(fmt, va_alist)
584 	char *fmt;
585 	va_dcl
586 #endif
587 {
588 	va_list ap;
589 
590 	/* No mutex needed; DDB pauses all processors. */
591 	va_start(ap, fmt);
592 	kprintf(fmt, TODDB, NULL, NULL, ap);
593 	va_end(ap);
594 }
595 
596 #endif /* DDB */
597 
598 
599 /*
600  * normal kernel printf functions: printf, vprintf, snprintf, vsnprintf
601  */
602 
603 /*
604  * printf: print a message to the console and the log
605  */
606 void
607 #ifdef __STDC__
608 printf(const char *fmt, ...)
609 #else
610 printf(fmt, va_alist)
611 	char *fmt;
612 	va_dcl
613 #endif
614 {
615 	va_list ap;
616 	int s;
617 
618 	KPRINTF_MUTEX_ENTER(s);
619 
620 	va_start(ap, fmt);
621 	kprintf(fmt, TOCONS | TOLOG, NULL, NULL, ap);
622 	va_end(ap);
623 
624 	KPRINTF_MUTEX_EXIT(s);
625 
626 	if (!panicstr)
627 		logwakeup();
628 }
629 
630 /*
631  * vprintf: print a message to the console and the log [already have
632  *	va_alist]
633  */
634 
635 void
636 vprintf(fmt, ap)
637 	const char *fmt;
638 	va_list ap;
639 {
640 	int s;
641 
642 	KPRINTF_MUTEX_ENTER(s);
643 
644 	kprintf(fmt, TOCONS | TOLOG, NULL, NULL, ap);
645 
646 	KPRINTF_MUTEX_EXIT(s);
647 
648 	if (!panicstr)
649 		logwakeup();
650 }
651 
652 /*
653  * sprintf: print a message to a buffer
654  */
655 int
656 #ifdef __STDC__
657 sprintf(char *buf, const char *fmt, ...)
658 #else
659 sprintf(buf, fmt, va_alist)
660         char *buf;
661         const char *cfmt;
662         va_dcl
663 #endif
664 {
665 	int retval;
666 	va_list ap;
667 
668 	va_start(ap, fmt);
669 	retval = kprintf(fmt, TOBUFONLY, NULL, buf, ap);
670 	va_end(ap);
671 	*(buf + retval) = 0;	/* null terminate */
672 	return(retval);
673 }
674 
675 /*
676  * vsprintf: print a message to a buffer [already have va_alist]
677  */
678 
679 int
680 vsprintf(buf, fmt, ap)
681 	char *buf;
682 	const char *fmt;
683 	va_list ap;
684 {
685 	int retval;
686 
687 	retval = kprintf(fmt, TOBUFONLY, NULL, buf, ap);
688 	*(buf + retval) = 0;	/* null terminate */
689 	return (retval);
690 }
691 
692 /*
693  * snprintf: print a message to a buffer
694  */
695 int
696 #ifdef __STDC__
697 snprintf(char *buf, size_t size, const char *fmt, ...)
698 #else
699 snprintf(buf, size, fmt, va_alist)
700         char *buf;
701         size_t size;
702         const char *cfmt;
703         va_dcl
704 #endif
705 {
706 	int retval;
707 	va_list ap;
708 	char *p;
709 
710 	if (size < 1)
711 		return (-1);
712 	p = buf + size - 1;
713 	va_start(ap, fmt);
714 	retval = kprintf(fmt, TOBUFONLY, &p, buf, ap);
715 	va_end(ap);
716 	*(p) = 0;	/* null terminate */
717 	return(retval);
718 }
719 
720 /*
721  * vsnprintf: print a message to a buffer [already have va_alist]
722  */
723 int
724 vsnprintf(buf, size, fmt, ap)
725         char *buf;
726         size_t size;
727         const char *fmt;
728         va_list ap;
729 {
730 	int retval;
731 	char *p;
732 
733 	if (size < 1)
734 		return (-1);
735 	p = buf + size - 1;
736 	retval = kprintf(fmt, TOBUFONLY, &p, buf, ap);
737 	*(p) = 0;	/* null terminate */
738 	return(retval);
739 }
740 
741 /*
742  * bitmask_snprintf: print an interpreted bitmask to a buffer
743  *
744  * => returns pointer to the buffer
745  */
746 char *
747 bitmask_snprintf(val, p, buf, buflen)
748 	u_quad_t val;
749 	const char *p;
750 	char *buf;
751 	size_t buflen;
752 {
753 	char *bp, *q;
754 	size_t left;
755 	char *sbase, snbuf[KPRINTF_BUFSIZE];
756 	int base, bit, ch, len, sep;
757 	u_quad_t field;
758 
759 	bp = buf;
760 	memset(buf, 0, buflen);
761 
762 	/*
763 	 * Always leave room for the trailing NULL.
764 	 */
765 	left = buflen - 1;
766 
767 	/*
768 	 * Print the value into the buffer.  Abort if there's not
769 	 * enough room.
770 	 */
771 	if (buflen < KPRINTF_BUFSIZE)
772 		return (buf);
773 
774 	ch = *p++;
775 	base = ch != '\177' ? ch : *p++;
776 	sbase = base == 8 ? "%qo" : base == 10 ? "%qd" : base == 16 ? "%qx" : 0;
777 	if (sbase == 0)
778 		return (buf);	/* punt if not oct, dec, or hex */
779 
780 	snprintf(snbuf, sizeof(snbuf), sbase, val);
781 	for (q = snbuf ; *q ; q++) {
782 		*bp++ = *q;
783 		left--;
784 	}
785 
786 	/*
787 	 * If the value we printed was 0 and we're using the old-style format,
788 	 * or if we don't have room for "<x>", we're done.
789 	 */
790 	if (((val == 0) && (ch != '\177')) || left < 3)
791 		return (buf);
792 
793 #define PUTBYTE(b, c, l)	\
794 	*(b)++ = (c);		\
795 	if (--(l) == 0)		\
796 		goto out;
797 #define PUTSTR(b, p, l) do {		\
798 	int c;				\
799 	while ((c = *(p)++) != 0) {	\
800 		*(b)++ = c;		\
801 		if (--(l) == 0)		\
802 			goto out;	\
803 	}				\
804 } while (0)
805 
806 	/*
807 	 * Chris Torek's new bitmask format is identified by a leading \177
808 	 */
809 	sep = '<';
810 	if (ch != '\177') {
811 		/* old (standard) format. */
812 		for (;(bit = *p++) != 0;) {
813 			if (val & (1 << (bit - 1))) {
814 				PUTBYTE(bp, sep, left);
815 				for (; (ch = *p) > ' '; ++p) {
816 					PUTBYTE(bp, ch, left);
817 				}
818 				sep = ',';
819 			} else
820 				for (; *p > ' '; ++p)
821 					continue;
822 		}
823 	} else {
824 		/* new quad-capable format; also does fields. */
825 		field = val;
826 		while ((ch = *p++) != '\0') {
827 			bit = *p++;	/* now 0-origin */
828 			switch (ch) {
829 			case 'b':
830 				if (((u_int)(val >> bit) & 1) == 0)
831 					goto skip;
832 				PUTBYTE(bp, sep, left);
833 				PUTSTR(bp, p, left);
834 				sep = ',';
835 				break;
836 			case 'f':
837 			case 'F':
838 				len = *p++;	/* field length */
839 				field = (val >> bit) & ((1ULL << len) - 1);
840 				if (ch == 'F')	/* just extract */
841 					break;
842 				PUTBYTE(bp, sep, left);
843 				sep = ',';
844 				PUTSTR(bp, p, left);
845 				PUTBYTE(bp, '=', left);
846 				sprintf(snbuf, sbase, field);
847 				q = snbuf; PUTSTR(bp, q, left);
848 				break;
849 			case '=':
850 			case ':':
851 				/*
852 				 * Here "bit" is actually a value instead,
853 				 * to be compared against the last field.
854 				 * This only works for values in [0..255],
855 				 * of course.
856 				 */
857 				if ((int)field != bit)
858 					goto skip;
859 				if (ch == '=')
860 					PUTBYTE(bp, '=', left);
861 				PUTSTR(bp, p, left);
862 				break;
863 			default:
864 			skip:
865 				while (*p++ != '\0')
866 					continue;
867 				break;
868 			}
869 		}
870 	}
871 	if (sep != '<')
872 		PUTBYTE(bp, '>', left);
873 
874 out:
875 	return (buf);
876 
877 #undef PUTBYTE
878 #undef PUTSTR
879 }
880 
881 /*
882  * kprintf: scaled down version of printf(3).
883  *
884  * this version based on vfprintf() from libc which was derived from
885  * software contributed to Berkeley by Chris Torek.
886  *
887  * NOTE: The kprintf mutex must be held if we're going TOBUF or TOCONS!
888  */
889 
890 /*
891  * macros for converting digits to letters and vice versa
892  */
893 #define	to_digit(c)	((c) - '0')
894 #define is_digit(c)	((unsigned)to_digit(c) <= 9)
895 #define	to_char(n)	((n) + '0')
896 
897 /*
898  * flags used during conversion.
899  */
900 #define	ALT		0x001		/* alternate form */
901 #define	HEXPREFIX	0x002		/* add 0x or 0X prefix */
902 #define	LADJUST		0x004		/* left adjustment */
903 #define	LONGDBL		0x008		/* long double; unimplemented */
904 #define	LONGINT		0x010		/* long integer */
905 #define	QUADINT		0x020		/* quad integer */
906 #define	SHORTINT	0x040		/* short integer */
907 #define	MAXINT		0x080		/* intmax_t */
908 #define	PTRINT		0x100		/* intptr_t */
909 #define	SIZEINT		0x200		/* size_t */
910 #define	ZEROPAD		0x400		/* zero (as opposed to blank) pad */
911 #define FPT		0x800		/* Floating point number */
912 
913 	/*
914 	 * To extend shorts properly, we need both signed and unsigned
915 	 * argument extraction methods.
916 	 */
917 #define	SARG() \
918 	(flags&MAXINT ? va_arg(ap, intmax_t) : \
919 	    flags&PTRINT ? va_arg(ap, intptr_t) : \
920 	    flags&SIZEINT ? va_arg(ap, ssize_t) : /* XXX */ \
921 	    flags&QUADINT ? va_arg(ap, quad_t) : \
922 	    flags&LONGINT ? va_arg(ap, long) : \
923 	    flags&SHORTINT ? (long)(short)va_arg(ap, int) : \
924 	    (long)va_arg(ap, int))
925 #define	UARG() \
926 	(flags&MAXINT ? va_arg(ap, uintmax_t) : \
927 	    flags&PTRINT ? va_arg(ap, uintptr_t) : \
928 	    flags&SIZEINT ? va_arg(ap, size_t) : \
929 	    flags&QUADINT ? va_arg(ap, u_quad_t) : \
930 	    flags&LONGINT ? va_arg(ap, u_long) : \
931 	    flags&SHORTINT ? (u_long)(u_short)va_arg(ap, int) : \
932 	    (u_long)va_arg(ap, u_int))
933 
934 #define KPRINTF_PUTCHAR(C) {						\
935 	if (oflags == TOBUFONLY) {					\
936 		if ((vp != NULL) && (sbuf == tailp)) {			\
937 			ret += 1;		/* indicate error */	\
938 			goto overflow;					\
939 		}							\
940 		*sbuf++ = (C);						\
941 	} else {							\
942 		putchar((C), oflags, (struct tty *)vp);			\
943 	}								\
944 }
945 
946 /*
947  * Guts of kernel printf.  Note, we already expect to be in a mutex!
948  */
949 static int
950 kprintf(fmt0, oflags, vp, sbuf, ap)
951 	const char *fmt0;
952 	int oflags;
953 	void *vp;
954 	char *sbuf;
955 	va_list ap;
956 {
957 	char *fmt;		/* format string */
958 	int ch;			/* character from fmt */
959 	int n;			/* handy integer (short term usage) */
960 	char *cp;		/* handy char pointer (short term usage) */
961 	int flags;		/* flags as above */
962 	int ret;		/* return value accumulator */
963 	int width;		/* width from format (%8d), or 0 */
964 	int prec;		/* precision from format (%.3d), or -1 */
965 	char sign;		/* sign prefix (' ', '+', '-', or \0) */
966 
967 	u_quad_t _uquad;	/* integer arguments %[diouxX] */
968 	enum { OCT, DEC, HEX } base;/* base for [diouxX] conversion */
969 	int dprec;		/* a copy of prec if [diouxX], 0 otherwise */
970 	int realsz;		/* field size expanded by dprec */
971 	int size;		/* size of converted field or string */
972 	char *xdigs;		/* digits for [xX] conversion */
973 	char buf[KPRINTF_BUFSIZE]; /* space for %c, %[diouxX] */
974 	char *tailp;		/* tail pointer for snprintf */
975 
976 	tailp = NULL;	/* XXX: shutup gcc */
977 	if (oflags == TOBUFONLY && (vp != NULL))
978 		tailp = *(char **)vp;
979 
980 	cp = NULL;	/* XXX: shutup gcc */
981 	size = 0;	/* XXX: shutup gcc */
982 
983 	fmt = (char *)fmt0;
984 	ret = 0;
985 
986 	xdigs = NULL;		/* XXX: shut up gcc warning */
987 
988 	/*
989 	 * Scan the format for conversions (`%' character).
990 	 */
991 	for (;;) {
992 		while (*fmt != '%' && *fmt) {
993 			ret++;
994 			KPRINTF_PUTCHAR(*fmt++);
995 		}
996 		if (*fmt == 0)
997 			goto done;
998 
999 		fmt++;		/* skip over '%' */
1000 
1001 		flags = 0;
1002 		dprec = 0;
1003 		width = 0;
1004 		prec = -1;
1005 		sign = '\0';
1006 
1007 rflag:		ch = *fmt++;
1008 reswitch:	switch (ch) {
1009 		case ' ':
1010 			/*
1011 			 * ``If the space and + flags both appear, the space
1012 			 * flag will be ignored.''
1013 			 *	-- ANSI X3J11
1014 			 */
1015 			if (!sign)
1016 				sign = ' ';
1017 			goto rflag;
1018 		case '#':
1019 			flags |= ALT;
1020 			goto rflag;
1021 		case '*':
1022 			/*
1023 			 * ``A negative field width argument is taken as a
1024 			 * - flag followed by a positive field width.''
1025 			 *	-- ANSI X3J11
1026 			 * They don't exclude field widths read from args.
1027 			 */
1028 			if ((width = va_arg(ap, int)) >= 0)
1029 				goto rflag;
1030 			width = -width;
1031 			/* FALLTHROUGH */
1032 		case '-':
1033 			flags |= LADJUST;
1034 			goto rflag;
1035 		case '+':
1036 			sign = '+';
1037 			goto rflag;
1038 		case '.':
1039 			if ((ch = *fmt++) == '*') {
1040 				n = va_arg(ap, int);
1041 				prec = n < 0 ? -1 : n;
1042 				goto rflag;
1043 			}
1044 			n = 0;
1045 			while (is_digit(ch)) {
1046 				n = 10 * n + to_digit(ch);
1047 				ch = *fmt++;
1048 			}
1049 			prec = n < 0 ? -1 : n;
1050 			goto reswitch;
1051 		case '0':
1052 			/*
1053 			 * ``Note that 0 is taken as a flag, not as the
1054 			 * beginning of a field width.''
1055 			 *	-- ANSI X3J11
1056 			 */
1057 			flags |= ZEROPAD;
1058 			goto rflag;
1059 		case '1': case '2': case '3': case '4':
1060 		case '5': case '6': case '7': case '8': case '9':
1061 			n = 0;
1062 			do {
1063 				n = 10 * n + to_digit(ch);
1064 				ch = *fmt++;
1065 			} while (is_digit(ch));
1066 			width = n;
1067 			goto reswitch;
1068 		case 'h':
1069 			flags |= SHORTINT;
1070 			goto rflag;
1071 		case 'j':
1072 			flags |= MAXINT;
1073 			goto rflag;
1074 		case 'l':
1075 			if (*fmt == 'l') {
1076 				fmt++;
1077 				flags |= QUADINT;
1078 			} else {
1079 				flags |= LONGINT;
1080 			}
1081 			goto rflag;
1082 		case 'q':
1083 			flags |= QUADINT;
1084 			goto rflag;
1085 		case 't':
1086 			flags |= PTRINT;
1087 			goto rflag;
1088 		case 'z':
1089 			flags |= SIZEINT;
1090 			goto rflag;
1091 		case 'c':
1092 			*(cp = buf) = va_arg(ap, int);
1093 			size = 1;
1094 			sign = '\0';
1095 			break;
1096 		case 'D':
1097 			flags |= LONGINT;
1098 			/*FALLTHROUGH*/
1099 		case 'd':
1100 		case 'i':
1101 			_uquad = SARG();
1102 			if ((quad_t)_uquad < 0) {
1103 				_uquad = -_uquad;
1104 				sign = '-';
1105 			}
1106 			base = DEC;
1107 			goto number;
1108 		case 'n':
1109 			if (flags & MAXINT)
1110 				*va_arg(ap, intmax_t *) = ret;
1111 			else if (flags & PTRINT)
1112 				*va_arg(ap, intptr_t *) = ret;
1113 			else if (flags & SIZEINT)
1114 				*va_arg(ap, ssize_t *) = ret;
1115 			else if (flags & QUADINT)
1116 				*va_arg(ap, quad_t *) = ret;
1117 			else if (flags & LONGINT)
1118 				*va_arg(ap, long *) = ret;
1119 			else if (flags & SHORTINT)
1120 				*va_arg(ap, short *) = ret;
1121 			else
1122 				*va_arg(ap, int *) = ret;
1123 			continue;	/* no output */
1124 		case 'O':
1125 			flags |= LONGINT;
1126 			/*FALLTHROUGH*/
1127 		case 'o':
1128 			_uquad = UARG();
1129 			base = OCT;
1130 			goto nosign;
1131 		case 'p':
1132 			/*
1133 			 * ``The argument shall be a pointer to void.  The
1134 			 * value of the pointer is converted to a sequence
1135 			 * of printable characters, in an implementation-
1136 			 * defined manner.''
1137 			 *	-- ANSI X3J11
1138 			 */
1139 			/* NOSTRICT */
1140 			_uquad = (u_long)va_arg(ap, void *);
1141 			base = HEX;
1142 			xdigs = "0123456789abcdef";
1143 			flags |= HEXPREFIX;
1144 			ch = 'x';
1145 			goto nosign;
1146 		case 's':
1147 			if ((cp = va_arg(ap, char *)) == NULL)
1148 				cp = "(null)";
1149 			if (prec >= 0) {
1150 				/*
1151 				 * can't use strlen; can only look for the
1152 				 * NUL in the first `prec' characters, and
1153 				 * strlen() will go further.
1154 				 */
1155 				char *p = memchr(cp, 0, prec);
1156 
1157 				if (p != NULL) {
1158 					size = p - cp;
1159 					if (size > prec)
1160 						size = prec;
1161 				} else
1162 					size = prec;
1163 			} else
1164 				size = strlen(cp);
1165 			sign = '\0';
1166 			break;
1167 		case 'U':
1168 			flags |= LONGINT;
1169 			/*FALLTHROUGH*/
1170 		case 'u':
1171 			_uquad = UARG();
1172 			base = DEC;
1173 			goto nosign;
1174 		case 'X':
1175 			xdigs = "0123456789ABCDEF";
1176 			goto hex;
1177 		case 'x':
1178 			xdigs = "0123456789abcdef";
1179 hex:			_uquad = UARG();
1180 			base = HEX;
1181 			/* leading 0x/X only if non-zero */
1182 			if (flags & ALT && _uquad != 0)
1183 				flags |= HEXPREFIX;
1184 
1185 			/* unsigned conversions */
1186 nosign:			sign = '\0';
1187 			/*
1188 			 * ``... diouXx conversions ... if a precision is
1189 			 * specified, the 0 flag will be ignored.''
1190 			 *	-- ANSI X3J11
1191 			 */
1192 number:			if ((dprec = prec) >= 0)
1193 				flags &= ~ZEROPAD;
1194 
1195 			/*
1196 			 * ``The result of converting a zero value with an
1197 			 * explicit precision of zero is no characters.''
1198 			 *	-- ANSI X3J11
1199 			 */
1200 			cp = buf + KPRINTF_BUFSIZE;
1201 			if (_uquad != 0 || prec != 0) {
1202 				/*
1203 				 * Unsigned mod is hard, and unsigned mod
1204 				 * by a constant is easier than that by
1205 				 * a variable; hence this switch.
1206 				 */
1207 				switch (base) {
1208 				case OCT:
1209 					do {
1210 						*--cp = to_char(_uquad & 7);
1211 						_uquad >>= 3;
1212 					} while (_uquad);
1213 					/* handle octal leading 0 */
1214 					if (flags & ALT && *cp != '0')
1215 						*--cp = '0';
1216 					break;
1217 
1218 				case DEC:
1219 					/* many numbers are 1 digit */
1220 					while (_uquad >= 10) {
1221 						*--cp = to_char(_uquad % 10);
1222 						_uquad /= 10;
1223 					}
1224 					*--cp = to_char(_uquad);
1225 					break;
1226 
1227 				case HEX:
1228 					do {
1229 						*--cp = xdigs[_uquad & 15];
1230 						_uquad >>= 4;
1231 					} while (_uquad);
1232 					break;
1233 
1234 				default:
1235 					cp = "bug in kprintf: bad base";
1236 					size = strlen(cp);
1237 					goto skipsize;
1238 				}
1239 			}
1240 			size = buf + KPRINTF_BUFSIZE - cp;
1241 		skipsize:
1242 			break;
1243 		default:	/* "%?" prints ?, unless ? is NUL */
1244 			if (ch == '\0')
1245 				goto done;
1246 			/* pretend it was %c with argument ch */
1247 			cp = buf;
1248 			*cp = ch;
1249 			size = 1;
1250 			sign = '\0';
1251 			break;
1252 		}
1253 
1254 		/*
1255 		 * All reasonable formats wind up here.  At this point, `cp'
1256 		 * points to a string which (if not flags&LADJUST) should be
1257 		 * padded out to `width' places.  If flags&ZEROPAD, it should
1258 		 * first be prefixed by any sign or other prefix; otherwise,
1259 		 * it should be blank padded before the prefix is emitted.
1260 		 * After any left-hand padding and prefixing, emit zeroes
1261 		 * required by a decimal [diouxX] precision, then print the
1262 		 * string proper, then emit zeroes required by any leftover
1263 		 * floating precision; finally, if LADJUST, pad with blanks.
1264 		 *
1265 		 * Compute actual size, so we know how much to pad.
1266 		 * size excludes decimal prec; realsz includes it.
1267 		 */
1268 		realsz = dprec > size ? dprec : size;
1269 		if (sign)
1270 			realsz++;
1271 		else if (flags & HEXPREFIX)
1272 			realsz+= 2;
1273 
1274 		/* adjust ret */
1275 		ret += width > realsz ? width : realsz;
1276 
1277 		/* right-adjusting blank padding */
1278 		if ((flags & (LADJUST|ZEROPAD)) == 0) {
1279 			n = width - realsz;
1280 			while (n-- > 0)
1281 				KPRINTF_PUTCHAR(' ');
1282 		}
1283 
1284 		/* prefix */
1285 		if (sign) {
1286 			KPRINTF_PUTCHAR(sign);
1287 		} else if (flags & HEXPREFIX) {
1288 			KPRINTF_PUTCHAR('0');
1289 			KPRINTF_PUTCHAR(ch);
1290 		}
1291 
1292 		/* right-adjusting zero padding */
1293 		if ((flags & (LADJUST|ZEROPAD)) == ZEROPAD) {
1294 			n = width - realsz;
1295 			while (n-- > 0)
1296 				KPRINTF_PUTCHAR('0');
1297 		}
1298 
1299 		/* leading zeroes from decimal precision */
1300 		n = dprec - size;
1301 		while (n-- > 0)
1302 			KPRINTF_PUTCHAR('0');
1303 
1304 		/* the string or number proper */
1305 		while (size--)
1306 			KPRINTF_PUTCHAR(*cp++);
1307 		/* left-adjusting padding (always blank) */
1308 		if (flags & LADJUST) {
1309 			n = width - realsz;
1310 			while (n-- > 0)
1311 				KPRINTF_PUTCHAR(' ');
1312 		}
1313 	}
1314 
1315 done:
1316 	if ((oflags == TOBUFONLY) && (vp != NULL))
1317 		*(char **)vp = sbuf;
1318 overflow:
1319 	return (ret);
1320 	/* NOTREACHED */
1321 }
1322