xref: /netbsd-src/sys/kern/subr_prf.c (revision df0caa2637da0538ecdf6b878c4d08e684b43d8f)
1 /*	$NetBSD: subr_prf.c,v 1.99 2005/06/23 18:46:17 thorpej 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. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  *	@(#)subr_prf.c	8.4 (Berkeley) 5/4/95
37  */
38 
39 #include <sys/cdefs.h>
40 __KERNEL_RCSID(0, "$NetBSD: subr_prf.c,v 1.99 2005/06/23 18:46:17 thorpej Exp $");
41 
42 #include "opt_ddb.h"
43 #include "opt_ipkdb.h"
44 #include "opt_kgdb.h"
45 #include "opt_multiprocessor.h"
46 #include "opt_dump.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 #include <sys/kprintf.h>
64 
65 #include <dev/cons.h>
66 
67 #ifdef DDB
68 #include <ddb/ddbvar.h>
69 #include <machine/db_machdep.h>
70 #include <ddb/db_command.h>
71 #include <ddb/db_interface.h>
72 #endif
73 
74 #ifdef IPKDB
75 #include <ipkdb/ipkdb.h>
76 #endif
77 
78 #if defined(MULTIPROCESSOR)
79 struct simplelock kprintf_slock = SIMPLELOCK_INITIALIZER;
80 #endif /* MULTIPROCESSOR */
81 
82 /*
83  * note that stdarg.h and the ansi style va_start macro is used for both
84  * ansi and traditional c complers.
85  * XXX: this requires that stdarg.h define: va_alist and va_dcl
86  */
87 #include <machine/stdarg.h>
88 
89 
90 #ifdef KGDB
91 #include <sys/kgdb.h>
92 #include <machine/cpu.h>
93 #endif
94 #ifdef DDB
95 #include <ddb/db_output.h>	/* db_printf, db_putchar prototypes */
96 #endif
97 
98 
99 /*
100  * defines
101  */
102 
103 /* max size buffer kprintf needs to print quad_t [size in base 8 + \0] */
104 #define KPRINTF_BUFSIZE		(sizeof(quad_t) * NBBY / 3 + 2)
105 
106 
107 /*
108  * local prototypes
109  */
110 
111 static void	 putchar(int, int, struct tty *);
112 
113 
114 /*
115  * globals
116  */
117 
118 extern	struct tty *constty;	/* pointer to console "window" tty */
119 extern	int log_open;	/* subr_log: is /dev/klog open? */
120 const	char *panicstr; /* arg to first call to panic (used as a flag
121 			   to indicate that panic has already been called). */
122 long	panicstart, panicend;	/* position in the msgbuf of the start and
123 				   end of the formatted panicstr. */
124 int	doing_shutdown;	/* set to indicate shutdown in progress */
125 
126 #ifndef	DUMP_ON_PANIC
127 #define	DUMP_ON_PANIC	1
128 #endif
129 int	dumponpanic = DUMP_ON_PANIC;
130 
131 /*
132  * v_putc: routine to putc on virtual console
133  *
134  * the v_putc pointer can be used to redirect the console cnputc elsewhere
135  * [e.g. to a "virtual console"].
136  */
137 
138 void (*v_putc)(int) = cnputc;	/* start with cnputc (normal cons) */
139 void (*v_flush)(void) = cnflush;	/* start with cnflush (normal cons) */
140 
141 const char hexdigits[] = "0123456789abcdef";
142 const char HEXDIGITS[] = "0123456789ABCDEF";
143 
144 
145 /*
146  * functions
147  */
148 
149 /*
150  * tablefull: warn that a system table is full
151  */
152 
153 void
154 tablefull(const char *tab, const char *hint)
155 {
156 	if (hint)
157 		log(LOG_ERR, "%s: table is full - %s\n", tab, hint);
158 	else
159 		log(LOG_ERR, "%s: table is full\n", tab);
160 }
161 
162 /*
163  * twiddle: spin a little propellor on the console.
164  */
165 
166 void
167 twiddle(void)
168 {
169 	static const char twiddle_chars[] = "|/-\\";
170 	static int pos;
171 	int s;
172 
173 	KPRINTF_MUTEX_ENTER(s);
174 
175 	putchar(twiddle_chars[pos++ & 3], TOCONS, NULL);
176 	putchar('\b', TOCONS, NULL);
177 
178 	KPRINTF_MUTEX_EXIT(s);
179 }
180 
181 /*
182  * panic: handle an unresolvable fatal error
183  *
184  * prints "panic: <message>" and reboots.   if called twice (i.e. recursive
185  * call) we avoid trying to sync the disk and just reboot (to avoid
186  * recursive panics).
187  */
188 
189 void
190 panic(const char *fmt, ...)
191 {
192 	int bootopt;
193 	va_list ap;
194 
195 	bootopt = RB_AUTOBOOT;
196 	if (dumponpanic)
197 		bootopt |= RB_DUMP;
198 	if (doing_shutdown)
199 		bootopt |= RB_NOSYNC;
200 	if (!panicstr)
201 		panicstr = fmt;
202 	doing_shutdown = 1;
203 
204 	if (msgbufenabled && msgbufp->msg_magic == MSG_MAGIC)
205 		panicstart = msgbufp->msg_bufx;
206 
207 	va_start(ap, fmt);
208 	printf("panic: ");
209 	vprintf(fmt, ap);
210 	printf("\n");
211 	va_end(ap);
212 
213 	if (msgbufenabled && msgbufp->msg_magic == MSG_MAGIC)
214 		panicend = msgbufp->msg_bufx;
215 
216 #ifdef IPKDB
217 	ipkdb_panic();
218 #endif
219 #ifdef KGDB
220 	kgdb_panic();
221 #endif
222 #ifdef KADB
223 	if (boothowto & RB_KDB)
224 		kdbpanic();
225 #endif
226 #ifdef DDB
227 	if (db_onpanic)
228 		Debugger();
229 	else {
230 		static int intrace = 0;
231 
232 		if (intrace==0) {
233 			intrace=1;
234 			printf("Begin traceback...\n");
235 			db_stack_trace_print(
236 			    (db_expr_t)(intptr_t)__builtin_frame_address(0),
237 			    TRUE, 65535, "", printf);
238 			printf("End traceback...\n");
239 			intrace=0;
240 		} else
241 			printf("Faulted in mid-traceback; aborting...");
242 	}
243 #endif
244 	cpu_reboot(bootopt, NULL);
245 }
246 
247 /*
248  * kernel logging functions: log, logpri, addlog
249  */
250 
251 /*
252  * log: write to the log buffer
253  *
254  * => will not sleep [so safe to call from interrupt]
255  * => will log to console if /dev/klog isn't open
256  */
257 
258 void
259 log(int level, const char *fmt, ...)
260 {
261 	int s;
262 	va_list ap;
263 
264 	KPRINTF_MUTEX_ENTER(s);
265 
266 	klogpri(level);		/* log the level first */
267 	va_start(ap, fmt);
268 	kprintf(fmt, TOLOG, NULL, NULL, ap);
269 	va_end(ap);
270 	if (!log_open) {
271 		va_start(ap, fmt);
272 		kprintf(fmt, TOCONS, NULL, NULL, ap);
273 		va_end(ap);
274 	}
275 
276 	KPRINTF_MUTEX_EXIT(s);
277 
278 	logwakeup();		/* wake up anyone waiting for log msgs */
279 }
280 
281 /*
282  * vlog: write to the log buffer [already have va_alist]
283  */
284 
285 void
286 vlog(int level, const char *fmt, va_list ap)
287 {
288 	int s;
289 
290 	KPRINTF_MUTEX_ENTER(s);
291 
292 	klogpri(level);		/* log the level first */
293 	kprintf(fmt, TOLOG, NULL, NULL, ap);
294 	if (!log_open)
295 		kprintf(fmt, TOCONS, NULL, NULL, ap);
296 
297 	KPRINTF_MUTEX_EXIT(s);
298 
299 	logwakeup();		/* wake up anyone waiting for log msgs */
300 }
301 
302 /*
303  * logpri: log the priority level to the klog
304  */
305 
306 void
307 logpri(int level)
308 {
309 	int s;
310 
311 	KPRINTF_MUTEX_ENTER(s);
312 	klogpri(level);
313 	KPRINTF_MUTEX_EXIT(s);
314 }
315 
316 /*
317  * Note: we must be in the mutex here!
318  */
319 void
320 klogpri(int level)
321 {
322 	char *p;
323 	char snbuf[KPRINTF_BUFSIZE];
324 
325 	putchar('<', TOLOG, NULL);
326 	snprintf(snbuf, sizeof(snbuf), "%d", level);
327 	for (p = snbuf ; *p ; p++)
328 		putchar(*p, TOLOG, NULL);
329 	putchar('>', TOLOG, NULL);
330 }
331 
332 /*
333  * addlog: add info to previous log message
334  */
335 
336 void
337 addlog(const char *fmt, ...)
338 {
339 	int s;
340 	va_list ap;
341 
342 	KPRINTF_MUTEX_ENTER(s);
343 
344 	va_start(ap, fmt);
345 	kprintf(fmt, TOLOG, NULL, NULL, ap);
346 	va_end(ap);
347 	if (!log_open) {
348 		va_start(ap, fmt);
349 		kprintf(fmt, TOCONS, NULL, NULL, ap);
350 		va_end(ap);
351 	}
352 
353 	KPRINTF_MUTEX_EXIT(s);
354 
355 	logwakeup();
356 }
357 
358 
359 /*
360  * putchar: print a single character on console or user terminal.
361  *
362  * => if console, then the last MSGBUFS chars are saved in msgbuf
363  *	for inspection later (e.g. dmesg/syslog)
364  * => we must already be in the mutex!
365  */
366 static void
367 putchar(int c, int flags, struct tty *tp)
368 {
369 	struct kern_msgbuf *mbp;
370 
371 	if (panicstr)
372 		constty = NULL;
373 	if ((flags & TOCONS) && tp == NULL && constty) {
374 		tp = constty;
375 		flags |= TOTTY;
376 	}
377 	if ((flags & TOTTY) && tp &&
378 	    tputchar(c, flags, tp) < 0 &&
379 	    (flags & TOCONS) && tp == constty)
380 		constty = NULL;
381 	if ((flags & TOLOG) &&
382 	    c != '\0' && c != '\r' && c != 0177 && msgbufenabled) {
383 		mbp = msgbufp;
384 		if (mbp->msg_magic != MSG_MAGIC) {
385 			/*
386 			 * Arguably should panic or somehow notify the
387 			 * user...  but how?  Panic may be too drastic,
388 			 * and would obliterate the message being kicked
389 			 * out (maybe a panic itself), and printf
390 			 * would invoke us recursively.  Silently punt
391 			 * for now.  If syslog is running, it should
392 			 * notice.
393 			 */
394 			msgbufenabled = 0;
395 		} else {
396 			mbp->msg_bufc[mbp->msg_bufx++] = c;
397 			if (mbp->msg_bufx < 0 || mbp->msg_bufx >= mbp->msg_bufs)
398 				mbp->msg_bufx = 0;
399 			/* If the buffer is full, keep the most recent data. */
400 			if (mbp->msg_bufr == mbp->msg_bufx) {
401 				 if (++mbp->msg_bufr >= mbp->msg_bufs)
402 					mbp->msg_bufr = 0;
403 			}
404 		}
405 	}
406 	if ((flags & TOCONS) && constty == NULL && c != '\0')
407 		(*v_putc)(c);
408 #ifdef DDB
409 	if (flags & TODDB)
410 		db_putchar(c);
411 #endif
412 }
413 
414 
415 /*
416  * uprintf: print to the controlling tty of the current process
417  *
418  * => we may block if the tty queue is full
419  * => no message is printed if the queue doesn't clear in a reasonable
420  *	time
421  */
422 
423 void
424 uprintf(const char *fmt, ...)
425 {
426 	struct proc *p = curproc;
427 	va_list ap;
428 
429 	if (p->p_flag & P_CONTROLT && p->p_session->s_ttyvp) {
430 		/* No mutex needed; going to process TTY. */
431 		va_start(ap, fmt);
432 		kprintf(fmt, TOTTY, p->p_session->s_ttyp, NULL, ap);
433 		va_end(ap);
434 	}
435 }
436 
437 /*
438  * tprintf functions: used to send messages to a specific process
439  *
440  * usage:
441  *   get a tpr_t handle on a process "p" by using "tprintf_open(p)"
442  *   use the handle when calling "tprintf"
443  *   when done, do a "tprintf_close" to drop the handle
444  */
445 
446 /*
447  * tprintf_open: get a tprintf handle on a process "p"
448  *
449  * => returns NULL if process can't be printed to
450  */
451 
452 tpr_t
453 tprintf_open(struct proc *p)
454 {
455 
456 	if (p->p_flag & P_CONTROLT && p->p_session->s_ttyvp) {
457 		SESSHOLD(p->p_session);
458 		return ((tpr_t) p->p_session);
459 	}
460 	return ((tpr_t) NULL);
461 }
462 
463 /*
464  * tprintf_close: dispose of a tprintf handle obtained with tprintf_open
465  */
466 
467 void
468 tprintf_close(tpr_t sess)
469 {
470 
471 	if (sess)
472 		SESSRELE((struct session *) sess);
473 }
474 
475 /*
476  * tprintf: given tprintf handle to a process [obtained with tprintf_open],
477  * send a message to the controlling tty for that process.
478  *
479  * => also sends message to /dev/klog
480  */
481 void
482 tprintf(tpr_t tpr, const char *fmt, ...)
483 {
484 	struct session *sess = (struct session *)tpr;
485 	struct tty *tp = NULL;
486 	int s, flags = TOLOG;
487 	va_list ap;
488 
489 	if (sess && sess->s_ttyvp && ttycheckoutq(sess->s_ttyp, 0)) {
490 		flags |= TOTTY;
491 		tp = sess->s_ttyp;
492 	}
493 
494 	KPRINTF_MUTEX_ENTER(s);
495 
496 	klogpri(LOG_INFO);
497 	va_start(ap, fmt);
498 	kprintf(fmt, flags, tp, NULL, ap);
499 	va_end(ap);
500 
501 	KPRINTF_MUTEX_EXIT(s);
502 
503 	logwakeup();
504 }
505 
506 
507 /*
508  * ttyprintf: send a message to a specific tty
509  *
510  * => should be used only by tty driver or anything that knows the
511  *    underlying tty will not be revoked(2)'d away.  [otherwise,
512  *    use tprintf]
513  */
514 void
515 ttyprintf(struct tty *tp, const char *fmt, ...)
516 {
517 	va_list ap;
518 
519 	/* No mutex needed; going to process TTY. */
520 	va_start(ap, fmt);
521 	kprintf(fmt, TOTTY, tp, NULL, ap);
522 	va_end(ap);
523 }
524 
525 #ifdef DDB
526 
527 /*
528  * db_printf: printf for DDB (via db_putchar)
529  */
530 
531 void
532 db_printf(const char *fmt, ...)
533 {
534 	va_list ap;
535 
536 	/* No mutex needed; DDB pauses all processors. */
537 	va_start(ap, fmt);
538 	kprintf(fmt, TODDB, NULL, NULL, ap);
539 	va_end(ap);
540 
541 	if (db_tee_msgbuf) {
542 		va_start(ap, fmt);
543 		kprintf(fmt, TOLOG, NULL, NULL, ap);
544 		va_end(ap);
545 	};
546 }
547 
548 void
549 db_vprintf(const char *fmt, va_list ap)
550 {
551 
552 	/* No mutex needed; DDB pauses all processors. */
553 	kprintf(fmt, TODDB, NULL, NULL, ap);
554 	if (db_tee_msgbuf)
555 		kprintf(fmt, TOLOG, NULL, NULL, ap);
556 }
557 
558 #endif /* DDB */
559 
560 /*
561  * Device autoconfiguration printf routines.  These change their
562  * behavior based on the AB_* flags in boothowto.  If AB_SILENT
563  * is set, messages never go to the console (but they still always
564  * go to the log).  AB_VERBOSE overrides AB_SILENT.
565  */
566 
567 /*
568  * aprint_normal: Send to console unless AB_QUIET.  Always goes
569  * to the log.
570  */
571 void
572 aprint_normal(const char *fmt, ...)
573 {
574 	va_list ap;
575 	int s, flags = TOLOG;
576 
577 	if ((boothowto & (AB_SILENT|AB_QUIET)) == 0 ||
578 	    (boothowto & AB_VERBOSE) != 0)
579 		flags |= TOCONS;
580 
581 	KPRINTF_MUTEX_ENTER(s);
582 
583 	va_start(ap, fmt);
584 	kprintf(fmt, flags, NULL, NULL, ap);
585 	va_end(ap);
586 
587 	KPRINTF_MUTEX_EXIT(s);
588 
589 	if (!panicstr)
590 		logwakeup();
591 }
592 
593 /*
594  * aprint_error: Send to console unless AB_QUIET.  Always goes
595  * to the log.  Also counts the number of times called so other
596  * parts of the kernel can report the number of errors during a
597  * given phase of system startup.
598  */
599 static int aprint_error_count;
600 
601 int
602 aprint_get_error_count(void)
603 {
604 	int count, s;
605 
606 	KPRINTF_MUTEX_ENTER(s);
607 
608 	count = aprint_error_count;
609 	aprint_error_count = 0;
610 
611 	KPRINTF_MUTEX_EXIT(s);
612 
613 	return (count);
614 }
615 
616 void
617 aprint_error(const char *fmt, ...)
618 {
619 	va_list ap;
620 	int s, flags = TOLOG;
621 
622 	if ((boothowto & (AB_SILENT|AB_QUIET)) == 0 ||
623 	    (boothowto & AB_VERBOSE) != 0)
624 		flags |= TOCONS;
625 
626 	KPRINTF_MUTEX_ENTER(s);
627 
628 	aprint_error_count++;
629 
630 	va_start(ap, fmt);
631 	kprintf(fmt, flags, NULL, NULL, ap);
632 	va_end(ap);
633 
634 	KPRINTF_MUTEX_EXIT(s);
635 
636 	if (!panicstr)
637 		logwakeup();
638 }
639 
640 /*
641  * aprint_naive: Send to console only if AB_QUIET.  Never goes
642  * to the log.
643  */
644 void
645 aprint_naive(const char *fmt, ...)
646 {
647 	va_list ap;
648 	int s;
649 
650 	if ((boothowto & (AB_QUIET|AB_SILENT|AB_VERBOSE)) == AB_QUIET) {
651 		KPRINTF_MUTEX_ENTER(s);
652 
653 		va_start(ap, fmt);
654 		kprintf(fmt, TOCONS, NULL, NULL, ap);
655 		va_end(ap);
656 
657 		KPRINTF_MUTEX_EXIT(s);
658 	}
659 }
660 
661 /*
662  * aprint_verbose: Send to console only if AB_VERBOSE.  Always
663  * goes to the log.
664  */
665 void
666 aprint_verbose(const char *fmt, ...)
667 {
668 	va_list ap;
669 	int s, flags = TOLOG;
670 
671 	if (boothowto & AB_VERBOSE)
672 		flags |= TOCONS;
673 
674 	KPRINTF_MUTEX_ENTER(s);
675 
676 	va_start(ap, fmt);
677 	kprintf(fmt, flags, NULL, NULL, ap);
678 	va_end(ap);
679 
680 	KPRINTF_MUTEX_EXIT(s);
681 
682 	if (!panicstr)
683 		logwakeup();
684 }
685 
686 /*
687  * aprint_debug: Send to console and log only if AB_DEBUG.
688  */
689 void
690 aprint_debug(const char *fmt, ...)
691 {
692 	va_list ap;
693 	int s;
694 
695 	if (boothowto & AB_DEBUG) {
696 		KPRINTF_MUTEX_ENTER(s);
697 
698 		va_start(ap, fmt);
699 		kprintf(fmt, TOCONS | TOLOG, NULL, NULL, ap);
700 		va_end(ap);
701 
702 		KPRINTF_MUTEX_EXIT(s);
703 	}
704 }
705 
706 /*
707  * printf_nolog: Like printf(), but does not send message to the log.
708  */
709 
710 void
711 printf_nolog(const char *fmt, ...)
712 {
713 	va_list ap;
714 	int s;
715 
716 	KPRINTF_MUTEX_ENTER(s);
717 
718 	va_start(ap, fmt);
719 	kprintf(fmt, TOCONS, NULL, NULL, ap);
720 	va_end(ap);
721 
722 	KPRINTF_MUTEX_EXIT(s);
723 }
724 
725 /*
726  * normal kernel printf functions: printf, vprintf, snprintf, vsnprintf
727  */
728 
729 /*
730  * printf: print a message to the console and the log
731  */
732 void
733 printf(const char *fmt, ...)
734 {
735 	va_list ap;
736 	int s;
737 
738 	KPRINTF_MUTEX_ENTER(s);
739 
740 	va_start(ap, fmt);
741 	kprintf(fmt, TOCONS | TOLOG, NULL, NULL, ap);
742 	va_end(ap);
743 
744 	KPRINTF_MUTEX_EXIT(s);
745 
746 	if (!panicstr)
747 		logwakeup();
748 }
749 
750 /*
751  * vprintf: print a message to the console and the log [already have
752  *	va_alist]
753  */
754 
755 void
756 vprintf(const char *fmt, va_list ap)
757 {
758 	int s;
759 
760 	KPRINTF_MUTEX_ENTER(s);
761 
762 	kprintf(fmt, TOCONS | TOLOG, NULL, NULL, ap);
763 
764 	KPRINTF_MUTEX_EXIT(s);
765 
766 	if (!panicstr)
767 		logwakeup();
768 }
769 
770 /*
771  * sprintf: print a message to a buffer
772  */
773 int
774 sprintf(char *bf, const char *fmt, ...)
775 {
776 	int retval;
777 	va_list ap;
778 
779 	va_start(ap, fmt);
780 	retval = kprintf(fmt, TOBUFONLY, NULL, bf, ap);
781 	va_end(ap);
782 	*(bf + retval) = 0;	/* null terminate */
783 	return(retval);
784 }
785 
786 /*
787  * vsprintf: print a message to a buffer [already have va_alist]
788  */
789 
790 int
791 vsprintf(char *bf, const char *fmt, va_list ap)
792 {
793 	int retval;
794 
795 	retval = kprintf(fmt, TOBUFONLY, NULL, bf, ap);
796 	*(bf + retval) = 0;	/* null terminate */
797 	return (retval);
798 }
799 
800 /*
801  * snprintf: print a message to a buffer
802  */
803 int
804 snprintf(char *bf, size_t size, const char *fmt, ...)
805 {
806 	int retval;
807 	va_list ap;
808 	char *p;
809 
810 	if (size < 1)
811 		return (-1);
812 	p = bf + size - 1;
813 	va_start(ap, fmt);
814 	retval = kprintf(fmt, TOBUFONLY, &p, bf, ap);
815 	va_end(ap);
816 	*(p) = 0;	/* null terminate */
817 	return(retval);
818 }
819 
820 /*
821  * vsnprintf: print a message to a buffer [already have va_alist]
822  */
823 int
824 vsnprintf(char *bf, size_t size, const char *fmt, va_list ap)
825 {
826 	int retval;
827 	char *p;
828 
829 	if (size < 1)
830 		return (-1);
831 	p = bf + size - 1;
832 	retval = kprintf(fmt, TOBUFONLY, &p, bf, ap);
833 	*(p) = 0;	/* null terminate */
834 	return(retval);
835 }
836 
837 /*
838  * bitmask_snprintf: print an interpreted bitmask to a buffer
839  *
840  * => returns pointer to the buffer
841  */
842 char *
843 bitmask_snprintf(u_quad_t val, const char *p, char *bf, size_t buflen)
844 {
845 	char *bp, *q;
846 	size_t left;
847 	const char *sbase;
848 	char snbuf[KPRINTF_BUFSIZE];
849 	int base, bit, ch, len, sep;
850 	u_quad_t field;
851 
852 	bp = bf;
853 	memset(bf, 0, buflen);
854 
855 	/*
856 	 * Always leave room for the trailing NULL.
857 	 */
858 	left = buflen - 1;
859 
860 	/*
861 	 * Print the value into the buffer.  Abort if there's not
862 	 * enough room.
863 	 */
864 	if (buflen < KPRINTF_BUFSIZE)
865 		return (bf);
866 
867 	ch = *p++;
868 	base = ch != '\177' ? ch : *p++;
869 	sbase = base == 8 ? "%qo" : base == 10 ? "%qd" : base == 16 ? "%qx" : 0;
870 	if (sbase == 0)
871 		return (bf);	/* punt if not oct, dec, or hex */
872 
873 	snprintf(snbuf, sizeof(snbuf), sbase, val);
874 	for (q = snbuf ; *q ; q++) {
875 		*bp++ = *q;
876 		left--;
877 	}
878 
879 	/*
880 	 * If the value we printed was 0 and we're using the old-style format,
881 	 * or if we don't have room for "<x>", we're done.
882 	 */
883 	if (((val == 0) && (ch != '\177')) || left < 3)
884 		return (bf);
885 
886 #define PUTBYTE(b, c, l) do {	\
887 	*(b)++ = (c);		\
888 	if (--(l) == 0)		\
889 		goto out;	\
890 } while (/*CONSTCOND*/ 0)
891 #define PUTSTR(b, p, l) do {		\
892 	int c;				\
893 	while ((c = *(p)++) != 0) {	\
894 		*(b)++ = c;		\
895 		if (--(l) == 0)		\
896 			goto out;	\
897 	}				\
898 } while (/*CONSTCOND*/ 0)
899 
900 	/*
901 	 * Chris Torek's new bitmask format is identified by a leading \177
902 	 */
903 	sep = '<';
904 	if (ch != '\177') {
905 		/* old (standard) format. */
906 		for (;(bit = *p++) != 0;) {
907 			if (val & (1 << (bit - 1))) {
908 				PUTBYTE(bp, sep, left);
909 				for (; (ch = *p) > ' '; ++p) {
910 					PUTBYTE(bp, ch, left);
911 				}
912 				sep = ',';
913 			} else
914 				for (; *p > ' '; ++p)
915 					continue;
916 		}
917 	} else {
918 		/* new quad-capable format; also does fields. */
919 		field = val;
920 		while ((ch = *p++) != '\0') {
921 			bit = *p++;	/* now 0-origin */
922 			switch (ch) {
923 			case 'b':
924 				if (((u_int)(val >> bit) & 1) == 0)
925 					goto skip;
926 				PUTBYTE(bp, sep, left);
927 				PUTSTR(bp, p, left);
928 				sep = ',';
929 				break;
930 			case 'f':
931 			case 'F':
932 				len = *p++;	/* field length */
933 				field = (val >> bit) & ((1ULL << len) - 1);
934 				if (ch == 'F')	/* just extract */
935 					break;
936 				PUTBYTE(bp, sep, left);
937 				sep = ',';
938 				PUTSTR(bp, p, left);
939 				PUTBYTE(bp, '=', left);
940 				sprintf(snbuf, sbase, field);
941 				q = snbuf; PUTSTR(bp, q, left);
942 				break;
943 			case '=':
944 			case ':':
945 				/*
946 				 * Here "bit" is actually a value instead,
947 				 * to be compared against the last field.
948 				 * This only works for values in [0..255],
949 				 * of course.
950 				 */
951 				if ((int)field != bit)
952 					goto skip;
953 				if (ch == '=')
954 					PUTBYTE(bp, '=', left);
955 				PUTSTR(bp, p, left);
956 				break;
957 			default:
958 			skip:
959 				while (*p++ != '\0')
960 					continue;
961 				break;
962 			}
963 		}
964 	}
965 	if (sep != '<')
966 		PUTBYTE(bp, '>', left);
967 
968 out:
969 	return (bf);
970 
971 #undef PUTBYTE
972 #undef PUTSTR
973 }
974 
975 /*
976  * kprintf: scaled down version of printf(3).
977  *
978  * this version based on vfprintf() from libc which was derived from
979  * software contributed to Berkeley by Chris Torek.
980  *
981  * NOTE: The kprintf mutex must be held if we're going TOBUF or TOCONS!
982  */
983 
984 /*
985  * macros for converting digits to letters and vice versa
986  */
987 #define	to_digit(c)	((c) - '0')
988 #define is_digit(c)	((unsigned)to_digit(c) <= 9)
989 #define	to_char(n)	((n) + '0')
990 
991 /*
992  * flags used during conversion.
993  */
994 #define	ALT		0x001		/* alternate form */
995 #define	HEXPREFIX	0x002		/* add 0x or 0X prefix */
996 #define	LADJUST		0x004		/* left adjustment */
997 #define	LONGDBL		0x008		/* long double; unimplemented */
998 #define	LONGINT		0x010		/* long integer */
999 #define	QUADINT		0x020		/* quad integer */
1000 #define	SHORTINT	0x040		/* short integer */
1001 #define	MAXINT		0x080		/* intmax_t */
1002 #define	PTRINT		0x100		/* intptr_t */
1003 #define	SIZEINT		0x200		/* size_t */
1004 #define	ZEROPAD		0x400		/* zero (as opposed to blank) pad */
1005 #define FPT		0x800		/* Floating point number */
1006 
1007 	/*
1008 	 * To extend shorts properly, we need both signed and unsigned
1009 	 * argument extraction methods.
1010 	 */
1011 #define	SARG() \
1012 	(flags&MAXINT ? va_arg(ap, intmax_t) : \
1013 	    flags&PTRINT ? va_arg(ap, intptr_t) : \
1014 	    flags&SIZEINT ? va_arg(ap, ssize_t) : /* XXX */ \
1015 	    flags&QUADINT ? va_arg(ap, quad_t) : \
1016 	    flags&LONGINT ? va_arg(ap, long) : \
1017 	    flags&SHORTINT ? (long)(short)va_arg(ap, int) : \
1018 	    (long)va_arg(ap, int))
1019 #define	UARG() \
1020 	(flags&MAXINT ? va_arg(ap, uintmax_t) : \
1021 	    flags&PTRINT ? va_arg(ap, uintptr_t) : \
1022 	    flags&SIZEINT ? va_arg(ap, size_t) : \
1023 	    flags&QUADINT ? va_arg(ap, u_quad_t) : \
1024 	    flags&LONGINT ? va_arg(ap, u_long) : \
1025 	    flags&SHORTINT ? (u_long)(u_short)va_arg(ap, int) : \
1026 	    (u_long)va_arg(ap, u_int))
1027 
1028 #define KPRINTF_PUTCHAR(C) {						\
1029 	if (oflags == TOBUFONLY) {					\
1030 		if ((vp != NULL) && (sbuf == tailp)) {			\
1031 			ret += 1;		/* indicate error */	\
1032 			goto overflow;					\
1033 		}							\
1034 		*sbuf++ = (C);						\
1035 	} else {							\
1036 		putchar((C), oflags, (struct tty *)vp);			\
1037 	}								\
1038 }
1039 
1040 /*
1041  * Guts of kernel printf.  Note, we already expect to be in a mutex!
1042  */
1043 int
1044 kprintf(const char *fmt0, int oflags, void *vp, char *sbuf, va_list ap)
1045 {
1046 	const char *fmt;	/* format string */
1047 	int ch;			/* character from fmt */
1048 	int n;			/* handy integer (short term usage) */
1049 	char *cp;		/* handy char pointer (short term usage) */
1050 	int flags;		/* flags as above */
1051 	int ret;		/* return value accumulator */
1052 	int width;		/* width from format (%8d), or 0 */
1053 	int prec;		/* precision from format (%.3d), or -1 */
1054 	char sign;		/* sign prefix (' ', '+', '-', or \0) */
1055 
1056 	u_quad_t _uquad;	/* integer arguments %[diouxX] */
1057 	enum { OCT, DEC, HEX } base;/* base for [diouxX] conversion */
1058 	int dprec;		/* a copy of prec if [diouxX], 0 otherwise */
1059 	int realsz;		/* field size expanded by dprec */
1060 	int size;		/* size of converted field or string */
1061 	const char *xdigs;	/* digits for [xX] conversion */
1062 	char bf[KPRINTF_BUFSIZE]; /* space for %c, %[diouxX] */
1063 	char *tailp;		/* tail pointer for snprintf */
1064 
1065 	tailp = NULL;	/* XXX: shutup gcc */
1066 	if (oflags == TOBUFONLY && (vp != NULL))
1067 		tailp = *(char **)vp;
1068 
1069 	cp = NULL;	/* XXX: shutup gcc */
1070 	size = 0;	/* XXX: shutup gcc */
1071 
1072 	fmt = fmt0;
1073 	ret = 0;
1074 
1075 	xdigs = NULL;		/* XXX: shut up gcc warning */
1076 
1077 	/*
1078 	 * Scan the format for conversions (`%' character).
1079 	 */
1080 	for (;;) {
1081 		while (*fmt != '%' && *fmt) {
1082 			ret++;
1083 			KPRINTF_PUTCHAR(*fmt++);
1084 		}
1085 		if (*fmt == 0)
1086 			goto done;
1087 
1088 		fmt++;		/* skip over '%' */
1089 
1090 		flags = 0;
1091 		dprec = 0;
1092 		width = 0;
1093 		prec = -1;
1094 		sign = '\0';
1095 
1096 rflag:		ch = *fmt++;
1097 reswitch:	switch (ch) {
1098 		case ' ':
1099 			/*
1100 			 * ``If the space and + flags both appear, the space
1101 			 * flag will be ignored.''
1102 			 *	-- ANSI X3J11
1103 			 */
1104 			if (!sign)
1105 				sign = ' ';
1106 			goto rflag;
1107 		case '#':
1108 			flags |= ALT;
1109 			goto rflag;
1110 		case '*':
1111 			/*
1112 			 * ``A negative field width argument is taken as a
1113 			 * - flag followed by a positive field width.''
1114 			 *	-- ANSI X3J11
1115 			 * They don't exclude field widths read from args.
1116 			 */
1117 			if ((width = va_arg(ap, int)) >= 0)
1118 				goto rflag;
1119 			width = -width;
1120 			/* FALLTHROUGH */
1121 		case '-':
1122 			flags |= LADJUST;
1123 			goto rflag;
1124 		case '+':
1125 			sign = '+';
1126 			goto rflag;
1127 		case '.':
1128 			if ((ch = *fmt++) == '*') {
1129 				n = va_arg(ap, int);
1130 				prec = n < 0 ? -1 : n;
1131 				goto rflag;
1132 			}
1133 			n = 0;
1134 			while (is_digit(ch)) {
1135 				n = 10 * n + to_digit(ch);
1136 				ch = *fmt++;
1137 			}
1138 			prec = n < 0 ? -1 : n;
1139 			goto reswitch;
1140 		case '0':
1141 			/*
1142 			 * ``Note that 0 is taken as a flag, not as the
1143 			 * beginning of a field width.''
1144 			 *	-- ANSI X3J11
1145 			 */
1146 			flags |= ZEROPAD;
1147 			goto rflag;
1148 		case '1': case '2': case '3': case '4':
1149 		case '5': case '6': case '7': case '8': case '9':
1150 			n = 0;
1151 			do {
1152 				n = 10 * n + to_digit(ch);
1153 				ch = *fmt++;
1154 			} while (is_digit(ch));
1155 			width = n;
1156 			goto reswitch;
1157 		case 'h':
1158 			flags |= SHORTINT;
1159 			goto rflag;
1160 		case 'j':
1161 			flags |= MAXINT;
1162 			goto rflag;
1163 		case 'l':
1164 			if (*fmt == 'l') {
1165 				fmt++;
1166 				flags |= QUADINT;
1167 			} else {
1168 				flags |= LONGINT;
1169 			}
1170 			goto rflag;
1171 		case 'q':
1172 			flags |= QUADINT;
1173 			goto rflag;
1174 		case 't':
1175 			flags |= PTRINT;
1176 			goto rflag;
1177 		case 'z':
1178 			flags |= SIZEINT;
1179 			goto rflag;
1180 		case 'c':
1181 			*(cp = bf) = va_arg(ap, int);
1182 			size = 1;
1183 			sign = '\0';
1184 			break;
1185 		case 'D':
1186 			flags |= LONGINT;
1187 			/*FALLTHROUGH*/
1188 		case 'd':
1189 		case 'i':
1190 			_uquad = SARG();
1191 			if ((quad_t)_uquad < 0) {
1192 				_uquad = -_uquad;
1193 				sign = '-';
1194 			}
1195 			base = DEC;
1196 			goto number;
1197 		case 'n':
1198 			if (flags & MAXINT)
1199 				*va_arg(ap, intmax_t *) = ret;
1200 			else if (flags & PTRINT)
1201 				*va_arg(ap, intptr_t *) = ret;
1202 			else if (flags & SIZEINT)
1203 				*va_arg(ap, ssize_t *) = ret;
1204 			else if (flags & QUADINT)
1205 				*va_arg(ap, quad_t *) = ret;
1206 			else if (flags & LONGINT)
1207 				*va_arg(ap, long *) = ret;
1208 			else if (flags & SHORTINT)
1209 				*va_arg(ap, short *) = ret;
1210 			else
1211 				*va_arg(ap, int *) = ret;
1212 			continue;	/* no output */
1213 		case 'O':
1214 			flags |= LONGINT;
1215 			/*FALLTHROUGH*/
1216 		case 'o':
1217 			_uquad = UARG();
1218 			base = OCT;
1219 			goto nosign;
1220 		case 'p':
1221 			/*
1222 			 * ``The argument shall be a pointer to void.  The
1223 			 * value of the pointer is converted to a sequence
1224 			 * of printable characters, in an implementation-
1225 			 * defined manner.''
1226 			 *	-- ANSI X3J11
1227 			 */
1228 			/* NOSTRICT */
1229 			_uquad = (u_long)va_arg(ap, void *);
1230 			base = HEX;
1231 			xdigs = hexdigits;
1232 			flags |= HEXPREFIX;
1233 			ch = 'x';
1234 			goto nosign;
1235 		case 's':
1236 			if ((cp = va_arg(ap, char *)) == NULL)
1237 				/*XXXUNCONST*/
1238 				cp = __UNCONST("(null)");
1239 			if (prec >= 0) {
1240 				/*
1241 				 * can't use strlen; can only look for the
1242 				 * NUL in the first `prec' characters, and
1243 				 * strlen() will go further.
1244 				 */
1245 				char *p = memchr(cp, 0, prec);
1246 
1247 				if (p != NULL) {
1248 					size = p - cp;
1249 					if (size > prec)
1250 						size = prec;
1251 				} else
1252 					size = prec;
1253 			} else
1254 				size = strlen(cp);
1255 			sign = '\0';
1256 			break;
1257 		case 'U':
1258 			flags |= LONGINT;
1259 			/*FALLTHROUGH*/
1260 		case 'u':
1261 			_uquad = UARG();
1262 			base = DEC;
1263 			goto nosign;
1264 		case 'X':
1265 			xdigs = hexdigits;
1266 			goto hex;
1267 		case 'x':
1268 			xdigs = hexdigits;
1269 hex:			_uquad = UARG();
1270 			base = HEX;
1271 			/* leading 0x/X only if non-zero */
1272 			if (flags & ALT && _uquad != 0)
1273 				flags |= HEXPREFIX;
1274 
1275 			/* unsigned conversions */
1276 nosign:			sign = '\0';
1277 			/*
1278 			 * ``... diouXx conversions ... if a precision is
1279 			 * specified, the 0 flag will be ignored.''
1280 			 *	-- ANSI X3J11
1281 			 */
1282 number:			if ((dprec = prec) >= 0)
1283 				flags &= ~ZEROPAD;
1284 
1285 			/*
1286 			 * ``The result of converting a zero value with an
1287 			 * explicit precision of zero is no characters.''
1288 			 *	-- ANSI X3J11
1289 			 */
1290 			cp = bf + KPRINTF_BUFSIZE;
1291 			if (_uquad != 0 || prec != 0) {
1292 				/*
1293 				 * Unsigned mod is hard, and unsigned mod
1294 				 * by a constant is easier than that by
1295 				 * a variable; hence this switch.
1296 				 */
1297 				switch (base) {
1298 				case OCT:
1299 					do {
1300 						*--cp = to_char(_uquad & 7);
1301 						_uquad >>= 3;
1302 					} while (_uquad);
1303 					/* handle octal leading 0 */
1304 					if (flags & ALT && *cp != '0')
1305 						*--cp = '0';
1306 					break;
1307 
1308 				case DEC:
1309 					/* many numbers are 1 digit */
1310 					while (_uquad >= 10) {
1311 						*--cp = to_char(_uquad % 10);
1312 						_uquad /= 10;
1313 					}
1314 					*--cp = to_char(_uquad);
1315 					break;
1316 
1317 				case HEX:
1318 					do {
1319 						*--cp = xdigs[_uquad & 15];
1320 						_uquad >>= 4;
1321 					} while (_uquad);
1322 					break;
1323 
1324 				default:
1325 					/*XXXUNCONST*/
1326 					cp = __UNCONST("bug in kprintf: bad base");
1327 					size = strlen(cp);
1328 					goto skipsize;
1329 				}
1330 			}
1331 			size = bf + KPRINTF_BUFSIZE - cp;
1332 		skipsize:
1333 			break;
1334 		default:	/* "%?" prints ?, unless ? is NUL */
1335 			if (ch == '\0')
1336 				goto done;
1337 			/* pretend it was %c with argument ch */
1338 			cp = bf;
1339 			*cp = ch;
1340 			size = 1;
1341 			sign = '\0';
1342 			break;
1343 		}
1344 
1345 		/*
1346 		 * All reasonable formats wind up here.  At this point, `cp'
1347 		 * points to a string which (if not flags&LADJUST) should be
1348 		 * padded out to `width' places.  If flags&ZEROPAD, it should
1349 		 * first be prefixed by any sign or other prefix; otherwise,
1350 		 * it should be blank padded before the prefix is emitted.
1351 		 * After any left-hand padding and prefixing, emit zeroes
1352 		 * required by a decimal [diouxX] precision, then print the
1353 		 * string proper, then emit zeroes required by any leftover
1354 		 * floating precision; finally, if LADJUST, pad with blanks.
1355 		 *
1356 		 * Compute actual size, so we know how much to pad.
1357 		 * size excludes decimal prec; realsz includes it.
1358 		 */
1359 		realsz = dprec > size ? dprec : size;
1360 		if (sign)
1361 			realsz++;
1362 		else if (flags & HEXPREFIX)
1363 			realsz+= 2;
1364 
1365 		/* adjust ret */
1366 		ret += width > realsz ? width : realsz;
1367 
1368 		/* right-adjusting blank padding */
1369 		if ((flags & (LADJUST|ZEROPAD)) == 0) {
1370 			n = width - realsz;
1371 			while (n-- > 0)
1372 				KPRINTF_PUTCHAR(' ');
1373 		}
1374 
1375 		/* prefix */
1376 		if (sign) {
1377 			KPRINTF_PUTCHAR(sign);
1378 		} else if (flags & HEXPREFIX) {
1379 			KPRINTF_PUTCHAR('0');
1380 			KPRINTF_PUTCHAR(ch);
1381 		}
1382 
1383 		/* right-adjusting zero padding */
1384 		if ((flags & (LADJUST|ZEROPAD)) == ZEROPAD) {
1385 			n = width - realsz;
1386 			while (n-- > 0)
1387 				KPRINTF_PUTCHAR('0');
1388 		}
1389 
1390 		/* leading zeroes from decimal precision */
1391 		n = dprec - size;
1392 		while (n-- > 0)
1393 			KPRINTF_PUTCHAR('0');
1394 
1395 		/* the string or number proper */
1396 		while (size--)
1397 			KPRINTF_PUTCHAR(*cp++);
1398 		/* left-adjusting padding (always blank) */
1399 		if (flags & LADJUST) {
1400 			n = width - realsz;
1401 			while (n-- > 0)
1402 				KPRINTF_PUTCHAR(' ');
1403 		}
1404 	}
1405 
1406 done:
1407 	if ((oflags == TOBUFONLY) && (vp != NULL))
1408 		*(char **)vp = sbuf;
1409 	(*v_flush)();
1410 overflow:
1411 	return (ret);
1412 	/* NOTREACHED */
1413 }
1414