xref: /netbsd-src/sys/kern/subr_prf.c (revision 2a399c6883d870daece976daec6ffa7bb7f934ce)
1 /*	$NetBSD: subr_prf.c,v 1.47 1997/11/17 00:59:56 ross 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	8.3 (Berkeley) 1/21/94
41  */
42 
43 #include <sys/param.h>
44 #include <sys/systm.h>
45 #include <sys/buf.h>
46 #include <sys/conf.h>
47 #include <sys/reboot.h>
48 #include <sys/msgbuf.h>
49 #include <sys/proc.h>
50 #include <sys/ioctl.h>
51 #include <sys/vnode.h>
52 #include <sys/file.h>
53 #include <sys/tty.h>
54 #include <sys/tprintf.h>
55 #include <sys/syslog.h>
56 #include <sys/malloc.h>
57 
58 #include <dev/cons.h>
59 
60 /*
61  * note that stdarg.h and the ansi style va_start macro is used for both
62  * ansi and traditional c complers.
63  * XXX: this requires that stdarg.h define: va_alist and va_dcl
64  */
65 #include <machine/stdarg.h>
66 
67 #include "ipkdb.h"
68 
69 #ifdef KGDB
70 #include <sys/kgdb.h>
71 #include <machine/cpu.h>
72 #endif
73 #ifdef DDB
74 #include <ddb/db_output.h>	/* db_printf, db_putchar prototypes */
75 extern	int db_radix;		/* XXX: for non-standard '%r' format */
76 #endif
77 
78 
79 /*
80  * defines
81  */
82 
83 /* flags for kprintf */
84 #define TOCONS		0x01	/* to the console */
85 #define TOTTY		0x02	/* to the process' tty */
86 #define TOLOG		0x04	/* to the kernel message buffer */
87 #define TOBUFONLY	0x08	/* to the buffer (only) [for sprintf] */
88 #define TODDB		0x10	/* to ddb console */
89 
90 /* max size buffer kprintf needs to print quad_t [size in base 8 + \0] */
91 #define KPRINTF_BUFSIZE		(sizeof(quad_t) * NBBY / 3 + 2)
92 
93 
94 /*
95  * local prototypes
96  */
97 
98 static int	 kprintf __P((const char *, int, struct tty *,
99 				char *, va_list));
100 static void	 putchar __P((int, int, struct tty *));
101 
102 
103 /*
104  * globals
105  */
106 
107 struct	tty *constty;	/* pointer to console "window" tty */
108 int	consintr = 1;	/* ok to handle console interrupts? */
109 extern	int log_open;	/* subr_log: is /dev/klog open? */
110 const	char *panicstr; /* arg to first call to panic (used as a flag
111 			   to indicate that panic has already been called). */
112 
113 /*
114  * v_putc: routine to putc on virtual console
115  *
116  * the v_putc pointer can be used to redirect the console cnputc elsewhere
117  * [e.g. to a "virtual console"].
118  */
119 
120 void (*v_putc) __P((int)) = cnputc;	/* start with cnputc (normal cons) */
121 
122 
123 /*
124  * functions
125  */
126 
127 /*
128  * tablefull: warn that a system table is full
129  */
130 
131 void
132 tablefull(tab)
133 	const char *tab;
134 {
135 	log(LOG_ERR, "%s: table is full\n", tab);
136 }
137 
138 /*
139  * panic: handle an unresolvable fatal error
140  *
141  * prints "panic: <message>" and reboots.   if called twice (i.e. recursive
142  * call) we avoid trying to sync the disk and just reboot (to avoid
143  * recursive panics).
144  */
145 
146 void
147 #ifdef __STDC__
148 panic(const char *fmt, ...)
149 #else
150 panic(fmt, va_alist)
151 	char *fmt;
152 	va_dcl
153 #endif
154 {
155 	int bootopt;
156 	va_list ap;
157 
158 	bootopt = RB_AUTOBOOT | RB_DUMP;
159 	if (panicstr)
160 		bootopt |= RB_NOSYNC;
161 	else
162 		panicstr = fmt;
163 
164 	va_start(ap, fmt);
165 	printf("panic: ");
166 	vprintf(fmt, ap);
167 	printf("\n");
168 	va_end(ap);
169 
170 #if NIPKDB > 0
171 	ipkdb_panic();
172 #endif
173 #ifdef KGDB
174 	kgdb_panic();
175 #endif
176 #ifdef KADB
177 	if (boothowto & RB_KDB)
178 		kdbpanic();
179 #endif
180 #ifdef DDB
181 	if (db_onpanic)
182 		Debugger();
183 #endif
184 	cpu_reboot(bootopt, NULL);
185 }
186 
187 /*
188  * kernel logging functions: log, logpri, addlog
189  */
190 
191 /*
192  * log: write to the log buffer
193  *
194  * => will not sleep [so safe to call from interrupt]
195  * => will log to console if /dev/klog isn't open
196  */
197 
198 void
199 #ifdef __STDC__
200 log(int level, const char *fmt, ...)
201 #else
202 log(level, fmt, va_alist)
203 	int level;
204 	char *fmt;
205 	va_dcl
206 #endif
207 {
208 	register int s;
209 	va_list ap;
210 
211 	s = splhigh();
212 	logpri(level);		/* log the level first */
213 	va_start(ap, fmt);
214 	kprintf(fmt, TOLOG, NULL, NULL, ap);
215 	splx(s);
216 	va_end(ap);
217 	if (!log_open) {
218 		va_start(ap, fmt);
219 		kprintf(fmt, TOCONS, NULL, NULL, ap);
220 		va_end(ap);
221 	}
222 	logwakeup();		/* wake up anyone waiting for log msgs */
223 }
224 
225 /*
226  * logpri: log the priority level to the klog
227  */
228 
229 void			/* XXXCDC: should be static? */
230 logpri(level)
231 	int level;
232 {
233 	char *p;
234 	char snbuf[KPRINTF_BUFSIZE];
235 
236 	putchar('<', TOLOG, NULL);
237 	sprintf(snbuf, "%d", level);
238 	for (p = snbuf ; *p ; p++)
239 		putchar(*p, TOLOG, NULL);
240 	putchar('>', TOLOG, NULL);
241 }
242 
243 /*
244  * addlog: add info to previous log message
245  */
246 
247 void
248 #ifdef __STDC__
249 addlog(const char *fmt, ...)
250 #else
251 addlog(fmt, va_alist)
252 	char *fmt;
253 	va_dcl
254 #endif
255 {
256 	register int s;
257 	va_list ap;
258 
259 	s = splhigh();
260 	va_start(ap, fmt);
261 	kprintf(fmt, TOLOG, NULL, NULL, ap);
262 	splx(s);
263 	va_end(ap);
264 	if (!log_open) {
265 		va_start(ap, fmt);
266 		kprintf(fmt, TOCONS, NULL, NULL, ap);
267 		va_end(ap);
268 	}
269 	logwakeup();
270 }
271 
272 
273 /*
274  * putchar: print a single character on console or user terminal.
275  *
276  * => if console, then the last MSGBUFS chars are saved in msgbuf
277  *	for inspection later (e.g. dmesg/syslog)
278  */
279 static void
280 putchar(c, flags, tp)
281 	register int c;
282 	int flags;
283 	struct tty *tp;
284 {
285 	register struct kern_msgbuf *mbp;
286 
287 	if (panicstr)
288 		constty = NULL;
289 	if ((flags & TOCONS) && tp == NULL && constty) {
290 		tp = constty;
291 		flags |= TOTTY;
292 	}
293 	if ((flags & TOTTY) && tp && tputchar(c, tp) < 0 &&
294 	    (flags & TOCONS) && tp == constty)
295 		constty = NULL;
296 	if ((flags & TOLOG) &&
297 	    c != '\0' && c != '\r' && c != 0177 && msgbufenabled) {
298 		mbp = msgbufp;
299 		if (mbp->msg_magic != MSG_MAGIC) {
300 			/*
301 			 * Arguably should panic or somehow notify the
302 			 * user...  but how?  Panic may be too drastic,
303 			 * and would obliterate the message being kicked
304 			 * out (maybe a panic itself), and printf
305 			 * would invoke us recursively.  Silently punt
306 			 * for now.  If syslog is running, it should
307 			 * notice.
308 			 */
309 			msgbufenabled = 0;
310 		} else {
311 			mbp->msg_bufc[mbp->msg_bufx++] = c;
312 			if (mbp->msg_bufx < 0 || mbp->msg_bufx >= mbp->msg_bufs)
313 				mbp->msg_bufx = 0;
314 		}
315 	}
316 	if ((flags & TOCONS) && constty == NULL && c != '\0')
317 		(*v_putc)(c);
318 #ifdef DDB
319 	if (flags & TODDB)
320 		db_putchar(c);
321 #endif
322 }
323 
324 
325 /*
326  * uprintf: print to the controlling tty of the current process
327  *
328  * => we may block if the tty queue is full
329  * => no message is printed if the queue doesn't clear in a reasonable
330  *	time
331  */
332 
333 void
334 #ifdef __STDC__
335 uprintf(const char *fmt, ...)
336 #else
337 uprintf(fmt, va_alist)
338 	char *fmt;
339 	va_dcl
340 #endif
341 {
342 	register struct proc *p = curproc;
343 	va_list ap;
344 
345 	if (p->p_flag & P_CONTROLT && p->p_session->s_ttyvp) {
346 		va_start(ap, fmt);
347 		kprintf(fmt, TOTTY, p->p_session->s_ttyp, NULL, ap);
348 		va_end(ap);
349 	}
350 }
351 
352 /*
353  * tprintf functions: used to send messages to a specific process
354  *
355  * usage:
356  *   get a tpr_t handle on a process "p" by using "tprintf_open(p)"
357  *   use the handle when calling "tprintf"
358  *   when done, do a "tprintf_close" to drop the handle
359  */
360 
361 /*
362  * tprintf_open: get a tprintf handle on a process "p"
363  *
364  * => returns NULL if process can't be printed to
365  */
366 
367 tpr_t
368 tprintf_open(p)
369 	register struct proc *p;
370 {
371 
372 	if (p->p_flag & P_CONTROLT && p->p_session->s_ttyvp) {
373 		SESSHOLD(p->p_session);
374 		return ((tpr_t) p->p_session);
375 	}
376 	return ((tpr_t) NULL);
377 }
378 
379 /*
380  * tprintf_close: dispose of a tprintf handle obtained with tprintf_open
381  */
382 
383 void
384 tprintf_close(sess)
385 	tpr_t sess;
386 {
387 
388 	if (sess)
389 		SESSRELE((struct session *) sess);
390 }
391 
392 /*
393  * tprintf: given tprintf handle to a process [obtained with tprintf_open],
394  * send a message to the controlling tty for that process.
395  *
396  * => also sends message to /dev/klog
397  */
398 void
399 #ifdef __STDC__
400 tprintf(tpr_t tpr, const char *fmt, ...)
401 #else
402 tprintf(tpr, fmt, va_alist)
403 	tpr_t tpr;
404 	char *fmt;
405 	va_dcl
406 #endif
407 {
408 	register struct session *sess = (struct session *)tpr;
409 	struct tty *tp = NULL;
410 	int flags = TOLOG;
411 	va_list ap;
412 
413 	logpri(LOG_INFO);
414 	if (sess && sess->s_ttyvp && ttycheckoutq(sess->s_ttyp, 0)) {
415 		flags |= TOTTY;
416 		tp = sess->s_ttyp;
417 	}
418 	va_start(ap, fmt);
419 	kprintf(fmt, flags, tp, NULL, ap);
420 	va_end(ap);
421 	logwakeup();
422 }
423 
424 
425 /*
426  * ttyprintf: send a message to a specific tty
427  *
428  * => should be used only by tty driver or anything that knows the
429  *	underlying tty will not be revoked(2)'d away.  [otherwise,
430  *	use tprintf]
431  */
432 void
433 #ifdef __STDC__
434 ttyprintf(struct tty *tp, const char *fmt, ...)
435 #else
436 ttyprintf(tp, fmt, va_alist)
437 	struct tty *tp;
438 	char *fmt;
439 	va_dcl
440 #endif
441 {
442 	va_list ap;
443 
444 	va_start(ap, fmt);
445 	kprintf(fmt, TOTTY, tp, NULL, ap);
446 	va_end(ap);
447 }
448 
449 #ifdef DDB
450 
451 /*
452  * db_printf: printf for DDB (via db_putchar)
453  */
454 
455 void
456 #ifdef __STDC__
457 db_printf(const char *fmt, ...)
458 #else
459 db_printf(fmt, va_alist)
460 	char *fmt;
461 	va_dcl
462 #endif
463 {
464 	va_list ap;
465 
466 	va_start(ap, fmt);
467 	kprintf(fmt, TODDB, NULL, NULL, ap);
468 	va_end(ap);
469 }
470 
471 #endif /* DDB */
472 
473 
474 /*
475  * normal kernel printf functions: printf, vprintf, sprintf
476  */
477 
478 /*
479  * printf: print a message to the console and the log
480  */
481 void
482 #ifdef __STDC__
483 printf(const char *fmt, ...)
484 #else
485 printf(fmt, va_alist)
486 	char *fmt;
487 	va_dcl
488 #endif
489 {
490 	va_list ap;
491 	int savintr;
492 
493 	savintr = consintr;		/* disable interrupts */
494 	consintr = 0;
495 	va_start(ap, fmt);
496 	kprintf(fmt, TOCONS | TOLOG, NULL, NULL, ap);
497 	va_end(ap);
498 	if (!panicstr)
499 		logwakeup();
500 	consintr = savintr;		/* reenable interrupts */
501 }
502 
503 /*
504  * vprintf: print a message to the console and the log [already have
505  *	va_alist]
506  */
507 
508 void
509 vprintf(fmt, ap)
510 	const char *fmt;
511 	va_list ap;
512 {
513 	int savintr;
514 
515 	savintr = consintr;		/* disable interrupts */
516 	consintr = 0;
517 	kprintf(fmt, TOCONS | TOLOG, NULL, NULL, ap);
518 	if (!panicstr)
519 		logwakeup();
520 	consintr = savintr;		/* reenable interrupts */
521 }
522 
523 /*
524  * sprintf: print a message to a buffer
525  */
526 int
527 #ifdef __STDC__
528 sprintf(char *buf, const char *fmt, ...)
529 #else
530 sprintf(buf, fmt, va_alist)
531         char *buf;
532         const char *cfmt;
533         va_dcl
534 #endif
535 {
536 	int retval;
537 	va_list ap;
538 
539 	va_start(ap, fmt);
540 	retval = kprintf(fmt, TOBUFONLY, NULL, buf, ap);
541 	va_end(ap);
542 	*(buf + retval) = 0;	/* null terminate */
543 	return(retval);
544 }
545 
546 /*
547  * bitmask_snprintf: print a kernel-printf "%b" message to a buffer
548  *
549  * => returns pointer to the buffer
550  * => XXX: useful vs. kernel %b?
551  */
552 char *
553 bitmask_snprintf(ul, p, buf, buflen)
554 	u_long ul;
555 	const char *p;
556 	char *buf;
557 	size_t buflen;
558 {
559 	char *bp, *q;
560 	size_t left;
561 	register int n;
562 	int tmp;
563 	char snbuf[KPRINTF_BUFSIZE];
564 
565 	bp = buf;
566 	bzero(buf, buflen);
567 
568 	/*
569 	 * Always leave room for the trailing NULL.
570 	 */
571 	left = buflen - 1;
572 
573 	/*
574 	 * Print the value into the buffer.  Abort if there's not
575 	 * enough room.
576 	 */
577 	if (buflen < KPRINTF_BUFSIZE)
578 		return (buf);
579 
580 	if (*p == 8)
581 		sprintf(snbuf,"%lo", ul);
582 	else if (*p == 10)
583 		sprintf(snbuf, "%ld", ul);
584 	else if (*p == 16)
585 		sprintf(snbuf, "%lx", ul);
586 	else
587 		return(buf);	/* punt if not oct, dec, or hex */
588 	p++;
589 
590 	for (q = snbuf ; *q ; q++) {
591 		*bp++ = *q;
592 		left--;
593 	}
594 
595 	/*
596 	 * If the value we printed was 0, or if we don't have room for
597 	 * "<x>", we're done.
598 	 */
599 	if (ul == 0 || left < 3)
600 		return (buf);
601 
602 #define PUTBYTE(b, c, l)	\
603 	*(b)++ = (c);		\
604 	if (--(l) == 0)		\
605 		goto out;
606 
607 	for (tmp = 0; (n = *p++) != 0;) {
608 		if (ul & (1 << (n - 1))) {
609 			PUTBYTE(bp, tmp ? ',' : '<', left);
610 				for (; (n = *p) > ' '; ++p) {
611 					PUTBYTE(bp, n, left);
612 				}
613 				tmp = 1;
614 		} else
615 			for (; *p > ' '; ++p)
616 				continue;
617 	}
618 	if (tmp)
619 		*bp = '>';
620 
621 #undef PUTBYTE
622 
623  out:
624 	return (buf);
625 }
626 
627 /*
628  * kprintf: scaled down version of printf(3).
629  *
630  * this version based on vfprintf() from libc which was derived from
631  * software contributed to Berkeley by Chris Torek.
632  *
633  * Two additional formats:
634  *
635  * The format %b is supported to decode error registers.
636  * Its usage is:
637  *
638  *	printf("reg=%b\n", regval, "<base><arg>*");
639  *
640  * where <base> is the output base expressed as a control character, e.g.
641  * \10 gives octal; \20 gives hex.  Each arg is a sequence of characters,
642  * the first of which gives the bit number to be inspected (origin 1), and
643  * the next characters (up to a control character, i.e. a character <= 32),
644  * give the name of the register.  Thus:
645  *
646  *	kprintf("reg=%b\n", 3, "\10\2BITTWO\1BITONE\n");
647  *
648  * would produce output:
649  *
650  *	reg=3<BITTWO,BITONE>
651  *
652  * The format %: passes an additional format string and argument list
653  * recursively.  Its usage is:
654  *
655  * fn(char *fmt, ...)
656  * {
657  *	va_list ap;
658  *	va_start(ap, fmt);
659  *	printf("prefix: %: suffix\n", fmt, ap);
660  *	va_end(ap);
661  * }
662  *
663  * this is the actual printf innards
664  *
665  * This code is large and complicated...
666  */
667 
668 /*
669  * macros for converting digits to letters and vice versa
670  */
671 #define	to_digit(c)	((c) - '0')
672 #define is_digit(c)	((unsigned)to_digit(c) <= 9)
673 #define	to_char(n)	((n) + '0')
674 
675 /*
676  * flags used during conversion.
677  */
678 #define	ALT		0x001		/* alternate form */
679 #define	HEXPREFIX	0x002		/* add 0x or 0X prefix */
680 #define	LADJUST		0x004		/* left adjustment */
681 #define	LONGDBL		0x008		/* long double; unimplemented */
682 #define	LONGINT		0x010		/* long integer */
683 #define	QUADINT		0x020		/* quad integer */
684 #define	SHORTINT	0x040		/* short integer */
685 #define	ZEROPAD		0x080		/* zero (as opposed to blank) pad */
686 #define FPT		0x100		/* Floating point number */
687 
688 	/*
689 	 * To extend shorts properly, we need both signed and unsigned
690 	 * argument extraction methods.
691 	 */
692 #define	SARG() \
693 	(flags&QUADINT ? va_arg(ap, quad_t) : \
694 	    flags&LONGINT ? va_arg(ap, long) : \
695 	    flags&SHORTINT ? (long)(short)va_arg(ap, int) : \
696 	    (long)va_arg(ap, int))
697 #define	UARG() \
698 	(flags&QUADINT ? va_arg(ap, u_quad_t) : \
699 	    flags&LONGINT ? va_arg(ap, u_long) : \
700 	    flags&SHORTINT ? (u_long)(u_short)va_arg(ap, int) : \
701 	    (u_long)va_arg(ap, u_int))
702 
703 #define KPRINTF_PUTCHAR(C) \
704 	(oflags == TOBUFONLY) ? *sbuf++ = (C) : putchar((C), oflags, tp);
705 
706 int
707 kprintf(fmt0, oflags, tp, sbuf, ap)
708 	const char *fmt0;
709 	int oflags;
710 	struct tty *tp;
711 	char *sbuf;
712 	va_list ap;
713 {
714 	char *fmt;		/* format string */
715 	int ch;			/* character from fmt */
716 	int n;			/* handy integer (short term usage) */
717 	char *cp;		/* handy char pointer (short term usage) */
718 	int flags;		/* flags as above */
719 	int ret;		/* return value accumulator */
720 	int width;		/* width from format (%8d), or 0 */
721 	int prec;		/* precision from format (%.3d), or -1 */
722 	char sign;		/* sign prefix (' ', '+', '-', or \0) */
723 
724 	u_quad_t _uquad;	/* integer arguments %[diouxX] */
725 	enum { OCT, DEC, HEX } base;/* base for [diouxX] conversion */
726 	int dprec;		/* a copy of prec if [diouxX], 0 otherwise */
727 	int realsz;		/* field size expanded by dprec */
728 	int size;		/* size of converted field or string */
729 	char *xdigs;		/* digits for [xX] conversion */
730 	char buf[KPRINTF_BUFSIZE]; /* space for %c, %[diouxX] */
731 
732 	cp = NULL;	/* XXX: shutup gcc */
733 	size = 0;	/* XXX: shutup gcc */
734 
735 	fmt = (char *)fmt0;
736 	ret = 0;
737 
738 	xdigs = NULL;		/* XXX: shut up gcc warning */
739 
740 	/*
741 	 * Scan the format for conversions (`%' character).
742 	 */
743 	for (;;) {
744 		while (*fmt != '%' && *fmt) {
745 			KPRINTF_PUTCHAR(*fmt++);
746 			ret++;
747 		}
748 		if (*fmt == 0)
749 			goto done;
750 
751 		fmt++;		/* skip over '%' */
752 
753 		flags = 0;
754 		dprec = 0;
755 		width = 0;
756 		prec = -1;
757 		sign = '\0';
758 
759 rflag:		ch = *fmt++;
760 reswitch:	switch (ch) {
761 		/* XXX: non-standard '%:' format */
762 #ifndef __powerpc__
763 		case ':':
764 			if (oflags != TOBUFONLY) {
765 				cp = va_arg(ap, char *);
766 				kprintf(cp, oflags, tp,
767 					NULL, va_arg(ap, va_list));
768 			}
769 			continue;	/* no output */
770 #endif
771 		/* XXX: non-standard '%b' format */
772 		case 'b': {
773 			char *b, *z;
774 			int tmp;
775 			_uquad = va_arg(ap, int);
776 			b = va_arg(ap, char *);
777 			if (*b == 8)
778 				sprintf(buf, "%qo", _uquad);
779 			else if (*b == 10)
780 				sprintf(buf, "%qd", _uquad);
781 			else if (*b == 16)
782 				sprintf(buf, "%qx", _uquad);
783 			else
784 				break;
785 			b++;
786 
787 			z = buf;
788 			while (*z) {
789 				KPRINTF_PUTCHAR(*z++);
790 				ret++;
791 			}
792 
793 			if (_uquad) {
794 				tmp = 0;
795 				while ((n = *b++) != 0) {
796 					if (_uquad & (1 << (n - 1))) {
797 						KPRINTF_PUTCHAR(tmp ? ',':'<');
798 						ret++;
799 						while ((n = *b) > ' ') {
800 							KPRINTF_PUTCHAR(n);
801 							ret++;
802 							b++;
803 						}
804 						tmp = 1;
805 					} else {
806 						while(*b > ' ')
807 							b++;
808 					}
809 				}
810 				if (tmp) {
811 					KPRINTF_PUTCHAR('>');
812 					ret++;
813 				}
814 			}
815 			continue;	/* no output */
816 		}
817 
818 #ifdef DDB
819 		/* XXX: non-standard '%r' format (print int in db_radix) */
820 		case 'r':
821 			if ((oflags & TODDB) == 0)
822 				goto default_case;
823 
824 			if (db_radix == 16)
825 				goto case_z;	/* signed hex */
826 			_uquad = SARG();
827 			if ((quad_t)_uquad < 0) {
828 				_uquad = -_uquad;
829 				sign = '-';
830 			}
831 			base = (db_radix == 8) ? OCT : DEC;
832 			goto number;
833 
834 
835 		/* XXX: non-standard '%z' format ("signed hex", a "hex %i")*/
836 		case 'z':
837 		case_z:
838 			if ((oflags & TODDB) == 0)
839 				goto default_case;
840 
841 			xdigs = "0123456789abcdef";
842 			ch = 'x';	/* the 'x' in '0x' (below) */
843 			_uquad = SARG();
844 			base = HEX;
845 			/* leading 0x/X only if non-zero */
846 			if (flags & ALT && _uquad != 0)
847 				flags |= HEXPREFIX;
848 			if ((quad_t)_uquad < 0) {
849 				_uquad = -_uquad;
850 				sign = '-';
851 			}
852 			goto number;
853 #endif
854 
855 		case ' ':
856 			/*
857 			 * ``If the space and + flags both appear, the space
858 			 * flag will be ignored.''
859 			 *	-- ANSI X3J11
860 			 */
861 			if (!sign)
862 				sign = ' ';
863 			goto rflag;
864 		case '#':
865 			flags |= ALT;
866 			goto rflag;
867 		case '*':
868 			/*
869 			 * ``A negative field width argument is taken as a
870 			 * - flag followed by a positive field width.''
871 			 *	-- ANSI X3J11
872 			 * They don't exclude field widths read from args.
873 			 */
874 			if ((width = va_arg(ap, int)) >= 0)
875 				goto rflag;
876 			width = -width;
877 			/* FALLTHROUGH */
878 		case '-':
879 			flags |= LADJUST;
880 			goto rflag;
881 		case '+':
882 			sign = '+';
883 			goto rflag;
884 		case '.':
885 			if ((ch = *fmt++) == '*') {
886 				n = va_arg(ap, int);
887 				prec = n < 0 ? -1 : n;
888 				goto rflag;
889 			}
890 			n = 0;
891 			while (is_digit(ch)) {
892 				n = 10 * n + to_digit(ch);
893 				ch = *fmt++;
894 			}
895 			prec = n < 0 ? -1 : n;
896 			goto reswitch;
897 		case '0':
898 			/*
899 			 * ``Note that 0 is taken as a flag, not as the
900 			 * beginning of a field width.''
901 			 *	-- ANSI X3J11
902 			 */
903 			flags |= ZEROPAD;
904 			goto rflag;
905 		case '1': case '2': case '3': case '4':
906 		case '5': case '6': case '7': case '8': case '9':
907 			n = 0;
908 			do {
909 				n = 10 * n + to_digit(ch);
910 				ch = *fmt++;
911 			} while (is_digit(ch));
912 			width = n;
913 			goto reswitch;
914 		case 'h':
915 			flags |= SHORTINT;
916 			goto rflag;
917 		case 'l':
918 			if (*fmt == 'l') {
919 				fmt++;
920 				flags |= QUADINT;
921 			} else {
922 				flags |= LONGINT;
923 			}
924 			goto rflag;
925 		case 'q':
926 			flags |= QUADINT;
927 			goto rflag;
928 		case 'c':
929 			*(cp = buf) = va_arg(ap, int);
930 			size = 1;
931 			sign = '\0';
932 			break;
933 		case 'D':
934 			flags |= LONGINT;
935 			/*FALLTHROUGH*/
936 		case 'd':
937 		case 'i':
938 			_uquad = SARG();
939 			if ((quad_t)_uquad < 0) {
940 				_uquad = -_uquad;
941 				sign = '-';
942 			}
943 			base = DEC;
944 			goto number;
945 		case 'n':
946 #ifdef DDB
947 		/* XXX: non-standard '%n' format */
948 		/*
949 		 * XXX: HACK!   DDB wants '%n' to be a '%u' printed
950 		 * in db_radix format.   this should die since '%n'
951 		 * is already defined in standard printf to write
952 		 * the number of chars printed so far to the arg (which
953 		 * should be a pointer.
954 		 */
955 			if (oflags & TODDB) {
956 				if (db_radix == 16)
957 					ch = 'x';	/* convert to %x */
958 				else if (db_radix == 8)
959 					ch = 'o';	/* convert to %o */
960 				else
961 					ch = 'u';	/* convert to %u */
962 
963 				/* ... and start again */
964 				goto reswitch;
965 			}
966 
967 #endif
968 			if (flags & QUADINT)
969 				*va_arg(ap, quad_t *) = ret;
970 			else if (flags & LONGINT)
971 				*va_arg(ap, long *) = ret;
972 			else if (flags & SHORTINT)
973 				*va_arg(ap, short *) = ret;
974 			else
975 				*va_arg(ap, int *) = ret;
976 			continue;	/* no output */
977 		case 'O':
978 			flags |= LONGINT;
979 			/*FALLTHROUGH*/
980 		case 'o':
981 			_uquad = UARG();
982 			base = OCT;
983 			goto nosign;
984 		case 'p':
985 			/*
986 			 * ``The argument shall be a pointer to void.  The
987 			 * value of the pointer is converted to a sequence
988 			 * of printable characters, in an implementation-
989 			 * defined manner.''
990 			 *	-- ANSI X3J11
991 			 */
992 			/* NOSTRICT */
993 			_uquad = (u_long)va_arg(ap, void *);
994 			base = HEX;
995 			xdigs = "0123456789abcdef";
996 			flags |= HEXPREFIX;
997 			ch = 'x';
998 			goto nosign;
999 		case 's':
1000 			if ((cp = va_arg(ap, char *)) == NULL)
1001 				cp = "(null)";
1002 			if (prec >= 0) {
1003 				/*
1004 				 * can't use strlen; can only look for the
1005 				 * NUL in the first `prec' characters, and
1006 				 * strlen() will go further.
1007 				 */
1008 				char *p = memchr(cp, 0, prec);
1009 
1010 				if (p != NULL) {
1011 					size = p - cp;
1012 					if (size > prec)
1013 						size = prec;
1014 				} else
1015 					size = prec;
1016 			} else
1017 				size = strlen(cp);
1018 			sign = '\0';
1019 			break;
1020 		case 'U':
1021 			flags |= LONGINT;
1022 			/*FALLTHROUGH*/
1023 		case 'u':
1024 			_uquad = UARG();
1025 			base = DEC;
1026 			goto nosign;
1027 		case 'X':
1028 			xdigs = "0123456789ABCDEF";
1029 			goto hex;
1030 		case 'x':
1031 			xdigs = "0123456789abcdef";
1032 hex:			_uquad = UARG();
1033 			base = HEX;
1034 			/* leading 0x/X only if non-zero */
1035 			if (flags & ALT && _uquad != 0)
1036 				flags |= HEXPREFIX;
1037 
1038 			/* unsigned conversions */
1039 nosign:			sign = '\0';
1040 			/*
1041 			 * ``... diouXx conversions ... if a precision is
1042 			 * specified, the 0 flag will be ignored.''
1043 			 *	-- ANSI X3J11
1044 			 */
1045 number:			if ((dprec = prec) >= 0)
1046 				flags &= ~ZEROPAD;
1047 
1048 			/*
1049 			 * ``The result of converting a zero value with an
1050 			 * explicit precision of zero is no characters.''
1051 			 *	-- ANSI X3J11
1052 			 */
1053 			cp = buf + KPRINTF_BUFSIZE;
1054 			if (_uquad != 0 || prec != 0) {
1055 				/*
1056 				 * Unsigned mod is hard, and unsigned mod
1057 				 * by a constant is easier than that by
1058 				 * a variable; hence this switch.
1059 				 */
1060 				switch (base) {
1061 				case OCT:
1062 					do {
1063 						*--cp = to_char(_uquad & 7);
1064 						_uquad >>= 3;
1065 					} while (_uquad);
1066 					/* handle octal leading 0 */
1067 					if (flags & ALT && *cp != '0')
1068 						*--cp = '0';
1069 					break;
1070 
1071 				case DEC:
1072 					/* many numbers are 1 digit */
1073 					while (_uquad >= 10) {
1074 						*--cp = to_char(_uquad % 10);
1075 						_uquad /= 10;
1076 					}
1077 					*--cp = to_char(_uquad);
1078 					break;
1079 
1080 				case HEX:
1081 					do {
1082 						*--cp = xdigs[_uquad & 15];
1083 						_uquad >>= 4;
1084 					} while (_uquad);
1085 					break;
1086 
1087 				default:
1088 					cp = "bug in kprintf: bad base";
1089 					size = strlen(cp);
1090 					goto skipsize;
1091 				}
1092 			}
1093 			size = buf + KPRINTF_BUFSIZE - cp;
1094 		skipsize:
1095 			break;
1096 		default:	/* "%?" prints ?, unless ? is NUL */
1097 #ifdef DDB
1098 		default_case:	/* DDB */
1099 #endif
1100 			if (ch == '\0')
1101 				goto done;
1102 			/* pretend it was %c with argument ch */
1103 			cp = buf;
1104 			*cp = ch;
1105 			size = 1;
1106 			sign = '\0';
1107 			break;
1108 		}
1109 
1110 		/*
1111 		 * All reasonable formats wind up here.  At this point, `cp'
1112 		 * points to a string which (if not flags&LADJUST) should be
1113 		 * padded out to `width' places.  If flags&ZEROPAD, it should
1114 		 * first be prefixed by any sign or other prefix; otherwise,
1115 		 * it should be blank padded before the prefix is emitted.
1116 		 * After any left-hand padding and prefixing, emit zeroes
1117 		 * required by a decimal [diouxX] precision, then print the
1118 		 * string proper, then emit zeroes required by any leftover
1119 		 * floating precision; finally, if LADJUST, pad with blanks.
1120 		 *
1121 		 * Compute actual size, so we know how much to pad.
1122 		 * size excludes decimal prec; realsz includes it.
1123 		 */
1124 		realsz = dprec > size ? dprec : size;
1125 		if (sign)
1126 			realsz++;
1127 		else if (flags & HEXPREFIX)
1128 			realsz+= 2;
1129 
1130 		/* right-adjusting blank padding */
1131 		if ((flags & (LADJUST|ZEROPAD)) == 0) {
1132 			n = width - realsz;
1133 			while (n-- > 0)
1134 				KPRINTF_PUTCHAR(' ');
1135 		}
1136 
1137 		/* prefix */
1138 		if (sign) {
1139 			KPRINTF_PUTCHAR(sign);
1140 		} else if (flags & HEXPREFIX) {
1141 			KPRINTF_PUTCHAR('0');
1142 			KPRINTF_PUTCHAR(ch);
1143 		}
1144 
1145 		/* right-adjusting zero padding */
1146 		if ((flags & (LADJUST|ZEROPAD)) == ZEROPAD) {
1147 			n = width - realsz;
1148 			while (n-- > 0)
1149 				KPRINTF_PUTCHAR('0');
1150 		}
1151 
1152 		/* leading zeroes from decimal precision */
1153 		n = dprec - size;
1154 		while (n-- > 0)
1155 			KPRINTF_PUTCHAR('0');
1156 
1157 		/* the string or number proper */
1158 		while (size--)
1159 			KPRINTF_PUTCHAR(*cp++);
1160 		/* left-adjusting padding (always blank) */
1161 		if (flags & LADJUST) {
1162 			n = width - realsz;
1163 			while (n-- > 0)
1164 				KPRINTF_PUTCHAR(' ');
1165 		}
1166 
1167 		/* finally, adjust ret */
1168 		ret += width > realsz ? width : realsz;
1169 
1170 	}
1171 done:
1172 	return (ret);
1173 	/* NOTREACHED */
1174 }
1175