xref: /netbsd-src/sys/kern/subr_prf.c (revision 7c7c171d130af9949261bc7dce2150a03c3d239c)
1 /*	$NetBSD: subr_prf.c,v 1.48 1998/03/01 02:22:31 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 <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 			/* If the buffer is full, keep the most recent data. */
315 			if (mbp->msg_bufr == mbp->msg_bufx) {
316 				 if (++mbp->msg_bufr >= mbp->msg_bufs)
317 					mbp->msg_bufr = 0;
318 			}
319 		}
320 	}
321 	if ((flags & TOCONS) && constty == NULL && c != '\0')
322 		(*v_putc)(c);
323 #ifdef DDB
324 	if (flags & TODDB)
325 		db_putchar(c);
326 #endif
327 }
328 
329 
330 /*
331  * uprintf: print to the controlling tty of the current process
332  *
333  * => we may block if the tty queue is full
334  * => no message is printed if the queue doesn't clear in a reasonable
335  *	time
336  */
337 
338 void
339 #ifdef __STDC__
340 uprintf(const char *fmt, ...)
341 #else
342 uprintf(fmt, va_alist)
343 	char *fmt;
344 	va_dcl
345 #endif
346 {
347 	register struct proc *p = curproc;
348 	va_list ap;
349 
350 	if (p->p_flag & P_CONTROLT && p->p_session->s_ttyvp) {
351 		va_start(ap, fmt);
352 		kprintf(fmt, TOTTY, p->p_session->s_ttyp, NULL, ap);
353 		va_end(ap);
354 	}
355 }
356 
357 /*
358  * tprintf functions: used to send messages to a specific process
359  *
360  * usage:
361  *   get a tpr_t handle on a process "p" by using "tprintf_open(p)"
362  *   use the handle when calling "tprintf"
363  *   when done, do a "tprintf_close" to drop the handle
364  */
365 
366 /*
367  * tprintf_open: get a tprintf handle on a process "p"
368  *
369  * => returns NULL if process can't be printed to
370  */
371 
372 tpr_t
373 tprintf_open(p)
374 	register struct proc *p;
375 {
376 
377 	if (p->p_flag & P_CONTROLT && p->p_session->s_ttyvp) {
378 		SESSHOLD(p->p_session);
379 		return ((tpr_t) p->p_session);
380 	}
381 	return ((tpr_t) NULL);
382 }
383 
384 /*
385  * tprintf_close: dispose of a tprintf handle obtained with tprintf_open
386  */
387 
388 void
389 tprintf_close(sess)
390 	tpr_t sess;
391 {
392 
393 	if (sess)
394 		SESSRELE((struct session *) sess);
395 }
396 
397 /*
398  * tprintf: given tprintf handle to a process [obtained with tprintf_open],
399  * send a message to the controlling tty for that process.
400  *
401  * => also sends message to /dev/klog
402  */
403 void
404 #ifdef __STDC__
405 tprintf(tpr_t tpr, const char *fmt, ...)
406 #else
407 tprintf(tpr, fmt, va_alist)
408 	tpr_t tpr;
409 	char *fmt;
410 	va_dcl
411 #endif
412 {
413 	register struct session *sess = (struct session *)tpr;
414 	struct tty *tp = NULL;
415 	int flags = TOLOG;
416 	va_list ap;
417 
418 	logpri(LOG_INFO);
419 	if (sess && sess->s_ttyvp && ttycheckoutq(sess->s_ttyp, 0)) {
420 		flags |= TOTTY;
421 		tp = sess->s_ttyp;
422 	}
423 	va_start(ap, fmt);
424 	kprintf(fmt, flags, tp, NULL, ap);
425 	va_end(ap);
426 	logwakeup();
427 }
428 
429 
430 /*
431  * ttyprintf: send a message to a specific tty
432  *
433  * => should be used only by tty driver or anything that knows the
434  *	underlying tty will not be revoked(2)'d away.  [otherwise,
435  *	use tprintf]
436  */
437 void
438 #ifdef __STDC__
439 ttyprintf(struct tty *tp, const char *fmt, ...)
440 #else
441 ttyprintf(tp, fmt, va_alist)
442 	struct tty *tp;
443 	char *fmt;
444 	va_dcl
445 #endif
446 {
447 	va_list ap;
448 
449 	va_start(ap, fmt);
450 	kprintf(fmt, TOTTY, tp, NULL, ap);
451 	va_end(ap);
452 }
453 
454 #ifdef DDB
455 
456 /*
457  * db_printf: printf for DDB (via db_putchar)
458  */
459 
460 void
461 #ifdef __STDC__
462 db_printf(const char *fmt, ...)
463 #else
464 db_printf(fmt, va_alist)
465 	char *fmt;
466 	va_dcl
467 #endif
468 {
469 	va_list ap;
470 
471 	va_start(ap, fmt);
472 	kprintf(fmt, TODDB, NULL, NULL, ap);
473 	va_end(ap);
474 }
475 
476 #endif /* DDB */
477 
478 
479 /*
480  * normal kernel printf functions: printf, vprintf, sprintf
481  */
482 
483 /*
484  * printf: print a message to the console and the log
485  */
486 void
487 #ifdef __STDC__
488 printf(const char *fmt, ...)
489 #else
490 printf(fmt, va_alist)
491 	char *fmt;
492 	va_dcl
493 #endif
494 {
495 	va_list ap;
496 	int savintr;
497 
498 	savintr = consintr;		/* disable interrupts */
499 	consintr = 0;
500 	va_start(ap, fmt);
501 	kprintf(fmt, TOCONS | TOLOG, NULL, NULL, ap);
502 	va_end(ap);
503 	if (!panicstr)
504 		logwakeup();
505 	consintr = savintr;		/* reenable interrupts */
506 }
507 
508 /*
509  * vprintf: print a message to the console and the log [already have
510  *	va_alist]
511  */
512 
513 void
514 vprintf(fmt, ap)
515 	const char *fmt;
516 	va_list ap;
517 {
518 	int savintr;
519 
520 	savintr = consintr;		/* disable interrupts */
521 	consintr = 0;
522 	kprintf(fmt, TOCONS | TOLOG, NULL, NULL, ap);
523 	if (!panicstr)
524 		logwakeup();
525 	consintr = savintr;		/* reenable interrupts */
526 }
527 
528 /*
529  * sprintf: print a message to a buffer
530  */
531 int
532 #ifdef __STDC__
533 sprintf(char *buf, const char *fmt, ...)
534 #else
535 sprintf(buf, fmt, va_alist)
536         char *buf;
537         const char *cfmt;
538         va_dcl
539 #endif
540 {
541 	int retval;
542 	va_list ap;
543 
544 	va_start(ap, fmt);
545 	retval = kprintf(fmt, TOBUFONLY, NULL, buf, ap);
546 	va_end(ap);
547 	*(buf + retval) = 0;	/* null terminate */
548 	return(retval);
549 }
550 
551 /*
552  * bitmask_snprintf: print a kernel-printf "%b" message to a buffer
553  *
554  * => returns pointer to the buffer
555  * => XXX: useful vs. kernel %b?
556  */
557 char *
558 bitmask_snprintf(ul, p, buf, buflen)
559 	u_long ul;
560 	const char *p;
561 	char *buf;
562 	size_t buflen;
563 {
564 	char *bp, *q;
565 	size_t left;
566 	register int n;
567 	int tmp;
568 	char snbuf[KPRINTF_BUFSIZE];
569 
570 	bp = buf;
571 	bzero(buf, buflen);
572 
573 	/*
574 	 * Always leave room for the trailing NULL.
575 	 */
576 	left = buflen - 1;
577 
578 	/*
579 	 * Print the value into the buffer.  Abort if there's not
580 	 * enough room.
581 	 */
582 	if (buflen < KPRINTF_BUFSIZE)
583 		return (buf);
584 
585 	if (*p == 8)
586 		sprintf(snbuf,"%lo", ul);
587 	else if (*p == 10)
588 		sprintf(snbuf, "%ld", ul);
589 	else if (*p == 16)
590 		sprintf(snbuf, "%lx", ul);
591 	else
592 		return(buf);	/* punt if not oct, dec, or hex */
593 	p++;
594 
595 	for (q = snbuf ; *q ; q++) {
596 		*bp++ = *q;
597 		left--;
598 	}
599 
600 	/*
601 	 * If the value we printed was 0, or if we don't have room for
602 	 * "<x>", we're done.
603 	 */
604 	if (ul == 0 || left < 3)
605 		return (buf);
606 
607 #define PUTBYTE(b, c, l)	\
608 	*(b)++ = (c);		\
609 	if (--(l) == 0)		\
610 		goto out;
611 
612 	for (tmp = 0; (n = *p++) != 0;) {
613 		if (ul & (1 << (n - 1))) {
614 			PUTBYTE(bp, tmp ? ',' : '<', left);
615 				for (; (n = *p) > ' '; ++p) {
616 					PUTBYTE(bp, n, left);
617 				}
618 				tmp = 1;
619 		} else
620 			for (; *p > ' '; ++p)
621 				continue;
622 	}
623 	if (tmp)
624 		*bp = '>';
625 
626 #undef PUTBYTE
627 
628  out:
629 	return (buf);
630 }
631 
632 /*
633  * kprintf: scaled down version of printf(3).
634  *
635  * this version based on vfprintf() from libc which was derived from
636  * software contributed to Berkeley by Chris Torek.
637  *
638  * Two additional formats:
639  *
640  * The format %b is supported to decode error registers.
641  * Its usage is:
642  *
643  *	printf("reg=%b\n", regval, "<base><arg>*");
644  *
645  * where <base> is the output base expressed as a control character, e.g.
646  * \10 gives octal; \20 gives hex.  Each arg is a sequence of characters,
647  * the first of which gives the bit number to be inspected (origin 1), and
648  * the next characters (up to a control character, i.e. a character <= 32),
649  * give the name of the register.  Thus:
650  *
651  *	kprintf("reg=%b\n", 3, "\10\2BITTWO\1BITONE\n");
652  *
653  * would produce output:
654  *
655  *	reg=3<BITTWO,BITONE>
656  *
657  * The format %: passes an additional format string and argument list
658  * recursively.  Its usage is:
659  *
660  * fn(char *fmt, ...)
661  * {
662  *	va_list ap;
663  *	va_start(ap, fmt);
664  *	printf("prefix: %: suffix\n", fmt, ap);
665  *	va_end(ap);
666  * }
667  *
668  * this is the actual printf innards
669  *
670  * This code is large and complicated...
671  */
672 
673 /*
674  * macros for converting digits to letters and vice versa
675  */
676 #define	to_digit(c)	((c) - '0')
677 #define is_digit(c)	((unsigned)to_digit(c) <= 9)
678 #define	to_char(n)	((n) + '0')
679 
680 /*
681  * flags used during conversion.
682  */
683 #define	ALT		0x001		/* alternate form */
684 #define	HEXPREFIX	0x002		/* add 0x or 0X prefix */
685 #define	LADJUST		0x004		/* left adjustment */
686 #define	LONGDBL		0x008		/* long double; unimplemented */
687 #define	LONGINT		0x010		/* long integer */
688 #define	QUADINT		0x020		/* quad integer */
689 #define	SHORTINT	0x040		/* short integer */
690 #define	ZEROPAD		0x080		/* zero (as opposed to blank) pad */
691 #define FPT		0x100		/* Floating point number */
692 
693 	/*
694 	 * To extend shorts properly, we need both signed and unsigned
695 	 * argument extraction methods.
696 	 */
697 #define	SARG() \
698 	(flags&QUADINT ? va_arg(ap, quad_t) : \
699 	    flags&LONGINT ? va_arg(ap, long) : \
700 	    flags&SHORTINT ? (long)(short)va_arg(ap, int) : \
701 	    (long)va_arg(ap, int))
702 #define	UARG() \
703 	(flags&QUADINT ? va_arg(ap, u_quad_t) : \
704 	    flags&LONGINT ? va_arg(ap, u_long) : \
705 	    flags&SHORTINT ? (u_long)(u_short)va_arg(ap, int) : \
706 	    (u_long)va_arg(ap, u_int))
707 
708 #define KPRINTF_PUTCHAR(C) \
709 	(oflags == TOBUFONLY) ? *sbuf++ = (C) : putchar((C), oflags, tp);
710 
711 int
712 kprintf(fmt0, oflags, tp, sbuf, ap)
713 	const char *fmt0;
714 	int oflags;
715 	struct tty *tp;
716 	char *sbuf;
717 	va_list ap;
718 {
719 	char *fmt;		/* format string */
720 	int ch;			/* character from fmt */
721 	int n;			/* handy integer (short term usage) */
722 	char *cp;		/* handy char pointer (short term usage) */
723 	int flags;		/* flags as above */
724 	int ret;		/* return value accumulator */
725 	int width;		/* width from format (%8d), or 0 */
726 	int prec;		/* precision from format (%.3d), or -1 */
727 	char sign;		/* sign prefix (' ', '+', '-', or \0) */
728 
729 	u_quad_t _uquad;	/* integer arguments %[diouxX] */
730 	enum { OCT, DEC, HEX } base;/* base for [diouxX] conversion */
731 	int dprec;		/* a copy of prec if [diouxX], 0 otherwise */
732 	int realsz;		/* field size expanded by dprec */
733 	int size;		/* size of converted field or string */
734 	char *xdigs;		/* digits for [xX] conversion */
735 	char buf[KPRINTF_BUFSIZE]; /* space for %c, %[diouxX] */
736 
737 	cp = NULL;	/* XXX: shutup gcc */
738 	size = 0;	/* XXX: shutup gcc */
739 
740 	fmt = (char *)fmt0;
741 	ret = 0;
742 
743 	xdigs = NULL;		/* XXX: shut up gcc warning */
744 
745 	/*
746 	 * Scan the format for conversions (`%' character).
747 	 */
748 	for (;;) {
749 		while (*fmt != '%' && *fmt) {
750 			KPRINTF_PUTCHAR(*fmt++);
751 			ret++;
752 		}
753 		if (*fmt == 0)
754 			goto done;
755 
756 		fmt++;		/* skip over '%' */
757 
758 		flags = 0;
759 		dprec = 0;
760 		width = 0;
761 		prec = -1;
762 		sign = '\0';
763 
764 rflag:		ch = *fmt++;
765 reswitch:	switch (ch) {
766 		/* XXX: non-standard '%:' format */
767 #ifndef __powerpc__
768 		case ':':
769 			if (oflags != TOBUFONLY) {
770 				cp = va_arg(ap, char *);
771 				kprintf(cp, oflags, tp,
772 					NULL, va_arg(ap, va_list));
773 			}
774 			continue;	/* no output */
775 #endif
776 		/* XXX: non-standard '%b' format */
777 		case 'b': {
778 			char *b, *z;
779 			int tmp;
780 			_uquad = va_arg(ap, int);
781 			b = va_arg(ap, char *);
782 			if (*b == 8)
783 				sprintf(buf, "%qo", _uquad);
784 			else if (*b == 10)
785 				sprintf(buf, "%qd", _uquad);
786 			else if (*b == 16)
787 				sprintf(buf, "%qx", _uquad);
788 			else
789 				break;
790 			b++;
791 
792 			z = buf;
793 			while (*z) {
794 				KPRINTF_PUTCHAR(*z++);
795 				ret++;
796 			}
797 
798 			if (_uquad) {
799 				tmp = 0;
800 				while ((n = *b++) != 0) {
801 					if (_uquad & (1 << (n - 1))) {
802 						KPRINTF_PUTCHAR(tmp ? ',':'<');
803 						ret++;
804 						while ((n = *b) > ' ') {
805 							KPRINTF_PUTCHAR(n);
806 							ret++;
807 							b++;
808 						}
809 						tmp = 1;
810 					} else {
811 						while(*b > ' ')
812 							b++;
813 					}
814 				}
815 				if (tmp) {
816 					KPRINTF_PUTCHAR('>');
817 					ret++;
818 				}
819 			}
820 			continue;	/* no output */
821 		}
822 
823 #ifdef DDB
824 		/* XXX: non-standard '%r' format (print int in db_radix) */
825 		case 'r':
826 			if ((oflags & TODDB) == 0)
827 				goto default_case;
828 
829 			if (db_radix == 16)
830 				goto case_z;	/* signed hex */
831 			_uquad = SARG();
832 			if ((quad_t)_uquad < 0) {
833 				_uquad = -_uquad;
834 				sign = '-';
835 			}
836 			base = (db_radix == 8) ? OCT : DEC;
837 			goto number;
838 
839 
840 		/* XXX: non-standard '%z' format ("signed hex", a "hex %i")*/
841 		case 'z':
842 		case_z:
843 			if ((oflags & TODDB) == 0)
844 				goto default_case;
845 
846 			xdigs = "0123456789abcdef";
847 			ch = 'x';	/* the 'x' in '0x' (below) */
848 			_uquad = SARG();
849 			base = HEX;
850 			/* leading 0x/X only if non-zero */
851 			if (flags & ALT && _uquad != 0)
852 				flags |= HEXPREFIX;
853 			if ((quad_t)_uquad < 0) {
854 				_uquad = -_uquad;
855 				sign = '-';
856 			}
857 			goto number;
858 #endif
859 
860 		case ' ':
861 			/*
862 			 * ``If the space and + flags both appear, the space
863 			 * flag will be ignored.''
864 			 *	-- ANSI X3J11
865 			 */
866 			if (!sign)
867 				sign = ' ';
868 			goto rflag;
869 		case '#':
870 			flags |= ALT;
871 			goto rflag;
872 		case '*':
873 			/*
874 			 * ``A negative field width argument is taken as a
875 			 * - flag followed by a positive field width.''
876 			 *	-- ANSI X3J11
877 			 * They don't exclude field widths read from args.
878 			 */
879 			if ((width = va_arg(ap, int)) >= 0)
880 				goto rflag;
881 			width = -width;
882 			/* FALLTHROUGH */
883 		case '-':
884 			flags |= LADJUST;
885 			goto rflag;
886 		case '+':
887 			sign = '+';
888 			goto rflag;
889 		case '.':
890 			if ((ch = *fmt++) == '*') {
891 				n = va_arg(ap, int);
892 				prec = n < 0 ? -1 : n;
893 				goto rflag;
894 			}
895 			n = 0;
896 			while (is_digit(ch)) {
897 				n = 10 * n + to_digit(ch);
898 				ch = *fmt++;
899 			}
900 			prec = n < 0 ? -1 : n;
901 			goto reswitch;
902 		case '0':
903 			/*
904 			 * ``Note that 0 is taken as a flag, not as the
905 			 * beginning of a field width.''
906 			 *	-- ANSI X3J11
907 			 */
908 			flags |= ZEROPAD;
909 			goto rflag;
910 		case '1': case '2': case '3': case '4':
911 		case '5': case '6': case '7': case '8': case '9':
912 			n = 0;
913 			do {
914 				n = 10 * n + to_digit(ch);
915 				ch = *fmt++;
916 			} while (is_digit(ch));
917 			width = n;
918 			goto reswitch;
919 		case 'h':
920 			flags |= SHORTINT;
921 			goto rflag;
922 		case 'l':
923 			if (*fmt == 'l') {
924 				fmt++;
925 				flags |= QUADINT;
926 			} else {
927 				flags |= LONGINT;
928 			}
929 			goto rflag;
930 		case 'q':
931 			flags |= QUADINT;
932 			goto rflag;
933 		case 'c':
934 			*(cp = buf) = va_arg(ap, int);
935 			size = 1;
936 			sign = '\0';
937 			break;
938 		case 'D':
939 			flags |= LONGINT;
940 			/*FALLTHROUGH*/
941 		case 'd':
942 		case 'i':
943 			_uquad = SARG();
944 			if ((quad_t)_uquad < 0) {
945 				_uquad = -_uquad;
946 				sign = '-';
947 			}
948 			base = DEC;
949 			goto number;
950 		case 'n':
951 #ifdef DDB
952 		/* XXX: non-standard '%n' format */
953 		/*
954 		 * XXX: HACK!   DDB wants '%n' to be a '%u' printed
955 		 * in db_radix format.   this should die since '%n'
956 		 * is already defined in standard printf to write
957 		 * the number of chars printed so far to the arg (which
958 		 * should be a pointer.
959 		 */
960 			if (oflags & TODDB) {
961 				if (db_radix == 16)
962 					ch = 'x';	/* convert to %x */
963 				else if (db_radix == 8)
964 					ch = 'o';	/* convert to %o */
965 				else
966 					ch = 'u';	/* convert to %u */
967 
968 				/* ... and start again */
969 				goto reswitch;
970 			}
971 
972 #endif
973 			if (flags & QUADINT)
974 				*va_arg(ap, quad_t *) = ret;
975 			else if (flags & LONGINT)
976 				*va_arg(ap, long *) = ret;
977 			else if (flags & SHORTINT)
978 				*va_arg(ap, short *) = ret;
979 			else
980 				*va_arg(ap, int *) = ret;
981 			continue;	/* no output */
982 		case 'O':
983 			flags |= LONGINT;
984 			/*FALLTHROUGH*/
985 		case 'o':
986 			_uquad = UARG();
987 			base = OCT;
988 			goto nosign;
989 		case 'p':
990 			/*
991 			 * ``The argument shall be a pointer to void.  The
992 			 * value of the pointer is converted to a sequence
993 			 * of printable characters, in an implementation-
994 			 * defined manner.''
995 			 *	-- ANSI X3J11
996 			 */
997 			/* NOSTRICT */
998 			_uquad = (u_long)va_arg(ap, void *);
999 			base = HEX;
1000 			xdigs = "0123456789abcdef";
1001 			flags |= HEXPREFIX;
1002 			ch = 'x';
1003 			goto nosign;
1004 		case 's':
1005 			if ((cp = va_arg(ap, char *)) == NULL)
1006 				cp = "(null)";
1007 			if (prec >= 0) {
1008 				/*
1009 				 * can't use strlen; can only look for the
1010 				 * NUL in the first `prec' characters, and
1011 				 * strlen() will go further.
1012 				 */
1013 				char *p = memchr(cp, 0, prec);
1014 
1015 				if (p != NULL) {
1016 					size = p - cp;
1017 					if (size > prec)
1018 						size = prec;
1019 				} else
1020 					size = prec;
1021 			} else
1022 				size = strlen(cp);
1023 			sign = '\0';
1024 			break;
1025 		case 'U':
1026 			flags |= LONGINT;
1027 			/*FALLTHROUGH*/
1028 		case 'u':
1029 			_uquad = UARG();
1030 			base = DEC;
1031 			goto nosign;
1032 		case 'X':
1033 			xdigs = "0123456789ABCDEF";
1034 			goto hex;
1035 		case 'x':
1036 			xdigs = "0123456789abcdef";
1037 hex:			_uquad = UARG();
1038 			base = HEX;
1039 			/* leading 0x/X only if non-zero */
1040 			if (flags & ALT && _uquad != 0)
1041 				flags |= HEXPREFIX;
1042 
1043 			/* unsigned conversions */
1044 nosign:			sign = '\0';
1045 			/*
1046 			 * ``... diouXx conversions ... if a precision is
1047 			 * specified, the 0 flag will be ignored.''
1048 			 *	-- ANSI X3J11
1049 			 */
1050 number:			if ((dprec = prec) >= 0)
1051 				flags &= ~ZEROPAD;
1052 
1053 			/*
1054 			 * ``The result of converting a zero value with an
1055 			 * explicit precision of zero is no characters.''
1056 			 *	-- ANSI X3J11
1057 			 */
1058 			cp = buf + KPRINTF_BUFSIZE;
1059 			if (_uquad != 0 || prec != 0) {
1060 				/*
1061 				 * Unsigned mod is hard, and unsigned mod
1062 				 * by a constant is easier than that by
1063 				 * a variable; hence this switch.
1064 				 */
1065 				switch (base) {
1066 				case OCT:
1067 					do {
1068 						*--cp = to_char(_uquad & 7);
1069 						_uquad >>= 3;
1070 					} while (_uquad);
1071 					/* handle octal leading 0 */
1072 					if (flags & ALT && *cp != '0')
1073 						*--cp = '0';
1074 					break;
1075 
1076 				case DEC:
1077 					/* many numbers are 1 digit */
1078 					while (_uquad >= 10) {
1079 						*--cp = to_char(_uquad % 10);
1080 						_uquad /= 10;
1081 					}
1082 					*--cp = to_char(_uquad);
1083 					break;
1084 
1085 				case HEX:
1086 					do {
1087 						*--cp = xdigs[_uquad & 15];
1088 						_uquad >>= 4;
1089 					} while (_uquad);
1090 					break;
1091 
1092 				default:
1093 					cp = "bug in kprintf: bad base";
1094 					size = strlen(cp);
1095 					goto skipsize;
1096 				}
1097 			}
1098 			size = buf + KPRINTF_BUFSIZE - cp;
1099 		skipsize:
1100 			break;
1101 		default:	/* "%?" prints ?, unless ? is NUL */
1102 #ifdef DDB
1103 		default_case:	/* DDB */
1104 #endif
1105 			if (ch == '\0')
1106 				goto done;
1107 			/* pretend it was %c with argument ch */
1108 			cp = buf;
1109 			*cp = ch;
1110 			size = 1;
1111 			sign = '\0';
1112 			break;
1113 		}
1114 
1115 		/*
1116 		 * All reasonable formats wind up here.  At this point, `cp'
1117 		 * points to a string which (if not flags&LADJUST) should be
1118 		 * padded out to `width' places.  If flags&ZEROPAD, it should
1119 		 * first be prefixed by any sign or other prefix; otherwise,
1120 		 * it should be blank padded before the prefix is emitted.
1121 		 * After any left-hand padding and prefixing, emit zeroes
1122 		 * required by a decimal [diouxX] precision, then print the
1123 		 * string proper, then emit zeroes required by any leftover
1124 		 * floating precision; finally, if LADJUST, pad with blanks.
1125 		 *
1126 		 * Compute actual size, so we know how much to pad.
1127 		 * size excludes decimal prec; realsz includes it.
1128 		 */
1129 		realsz = dprec > size ? dprec : size;
1130 		if (sign)
1131 			realsz++;
1132 		else if (flags & HEXPREFIX)
1133 			realsz+= 2;
1134 
1135 		/* right-adjusting blank padding */
1136 		if ((flags & (LADJUST|ZEROPAD)) == 0) {
1137 			n = width - realsz;
1138 			while (n-- > 0)
1139 				KPRINTF_PUTCHAR(' ');
1140 		}
1141 
1142 		/* prefix */
1143 		if (sign) {
1144 			KPRINTF_PUTCHAR(sign);
1145 		} else if (flags & HEXPREFIX) {
1146 			KPRINTF_PUTCHAR('0');
1147 			KPRINTF_PUTCHAR(ch);
1148 		}
1149 
1150 		/* right-adjusting zero padding */
1151 		if ((flags & (LADJUST|ZEROPAD)) == ZEROPAD) {
1152 			n = width - realsz;
1153 			while (n-- > 0)
1154 				KPRINTF_PUTCHAR('0');
1155 		}
1156 
1157 		/* leading zeroes from decimal precision */
1158 		n = dprec - size;
1159 		while (n-- > 0)
1160 			KPRINTF_PUTCHAR('0');
1161 
1162 		/* the string or number proper */
1163 		while (size--)
1164 			KPRINTF_PUTCHAR(*cp++);
1165 		/* left-adjusting padding (always blank) */
1166 		if (flags & LADJUST) {
1167 			n = width - realsz;
1168 			while (n-- > 0)
1169 				KPRINTF_PUTCHAR(' ');
1170 		}
1171 
1172 		/* finally, adjust ret */
1173 		ret += width > realsz ? width : realsz;
1174 
1175 	}
1176 done:
1177 	return (ret);
1178 	/* NOTREACHED */
1179 }
1180