dump.c revision 1.29 1 /* $NetBSD: dump.c,v 1.29 2008/07/21 14:19:23 lukem Exp $ */
2
3 /*-
4 * Copyright (c) 1988, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 #ifndef lint
34 __COPYRIGHT("@(#) Copyright (c) 1988, 1993\
35 The Regents of the University of California. All rights reserved.");
36 #endif /* not lint */
37
38 #ifndef lint
39 #if 0
40 static char sccsid[] = "@(#)kdump.c 8.4 (Berkeley) 4/28/95";
41 #endif
42 __RCSID("$NetBSD: dump.c,v 1.29 2008/07/21 14:19:23 lukem Exp $");
43 #endif /* not lint */
44
45 #include <sys/param.h>
46 #define _KERNEL
47 #include <sys/errno.h>
48 #undef _KERNEL
49 #include <sys/ioctl.h>
50 #include <sys/time.h>
51 #include <sys/uio.h>
52 #include <sys/ktrace.h>
53 #include <sys/ptrace.h>
54 #include <sys/queue.h>
55
56 #include <err.h>
57 #include <signal.h>
58 #include <stdarg.h>
59 #include <stddef.h>
60 #include <stdio.h>
61 #include <stdlib.h>
62 #include <string.h>
63 #include <unistd.h>
64 #include <vis.h>
65
66 #include "ktrace.h"
67 #include "misc.h"
68 #include "setemul.h"
69
70 int timestamp, decimal, fancy = 1, tail, maxdata;
71
72 int width; /* Keep track of current columns. */
73
74 #include <sys/syscall.h>
75
76 static const char *const ptrace_ops[] = {
77 "PT_TRACE_ME", "PT_READ_I", "PT_READ_D", "PT_READ_U",
78 "PT_WRITE_I", "PT_WRITE_D", "PT_WRITE_U", "PT_CONTINUE",
79 "PT_KILL", "PT_ATTACH", "PT_DETACH",
80 };
81
82 struct ktr_entry {
83 TAILQ_ENTRY(ktr_entry) kte_list;
84 struct ktr_header kte_kth;
85 };
86
87 TAILQ_HEAD(kteq, ktr_entry) ktependq = TAILQ_HEAD_INITIALIZER(ktependq);
88
89 void argprint(const char *, register_t **, int *);
90 void dumpheader(struct ktr_header *);
91 int dumprecord(int, FILE *);
92 void flushpendq(struct ktr_entry *);
93 int fread_tail(void *, int, int, FILE *);
94 void genioprint(struct ktr_header *);
95 struct ktr_entry *
96 getpendq(struct ktr_header *, int, struct kteq *);
97 struct ktr_entry *
98 getrecord(FILE *);
99 void indent(int);
100 void ioctldecode(u_long);
101 void ktrcsw(struct ktr_entry *);
102 void ktremul(struct ktr_entry *);
103 void ktrgenio(struct ktr_entry *);
104 void ktrnamei(struct ktr_entry *);
105 void ktrpsig(struct ktr_entry *);
106 void ktrsyscall(struct ktr_entry *);
107 void ktrsysret(struct ktr_entry *);
108 void nameiargprint(const char *, struct ktr_header *, register_t **, int *);
109 void nameiprint(struct ktr_header *);
110 void newline(void);
111 void putpendq(struct ktr_entry *);
112 void syscallnameprint(int);
113 void syscallprint(struct ktr_header *);
114 void sysretprint(struct ktr_header *);
115 int wprintf(const char *, ...);
116 void *xrealloc(void *, size_t *, size_t);
117
118 int
119 wprintf(const char *fmt, ...)
120 {
121 va_list ap;
122 int w;
123
124 va_start(ap, fmt);
125 w = vprintf(fmt, ap);
126 if (w == -1)
127 warn("vprintf");
128 else
129 width += w;
130 va_end(ap);
131 return (w);
132 }
133
134 void
135 newline(void)
136 {
137
138 if (width > 0) {
139 printf("\n");
140 width = 0;
141 }
142 }
143
144 void
145 indent(int col)
146 {
147
148 while (width < col)
149 if (wprintf(" ") < 0)
150 break;
151 }
152
153 void *
154 xrealloc(void *p, size_t *siz, size_t req)
155 {
156
157 if (*siz < req) {
158 if (*siz == 0)
159 *siz = 1;
160 while (*siz < req)
161 *siz <<= 1;
162 p = realloc(p, *siz);
163 if (p == NULL)
164 err(EXIT_FAILURE, "realloc: %lu bytes",
165 (u_long)*siz);
166 }
167 return (p);
168 }
169
170 struct ktr_entry *
171 getrecord(FILE *fp)
172 {
173 struct ktr_entry *kte;
174 struct ktr_header *kth;
175 char *cp;
176 size_t siz, len;
177
178 siz = 0;
179 kte = xrealloc(NULL, &siz, sizeof(struct ktr_entry));
180 kth = &kte->kte_kth;
181 if (fread_tail(kth, sizeof(struct ktr_header), 1, fp) == 0) {
182 free(kte);
183 return (NULL);
184 }
185
186 if (kth->ktr_len < 0)
187 errx(EXIT_FAILURE, "bogus length 0x%x", kth->ktr_len);
188 len = kth->ktr_len;
189 if (len > 0) {
190 /* + 1 to ensure room for NUL terminate */
191 kte = xrealloc(kte, &siz, sizeof(struct ktr_entry) + len + 1);
192 if (fread_tail(cp = (char *)(&kte->kte_kth + 1),
193 len, 1, fp) == 0)
194 errx(EXIT_FAILURE, "data too short");
195 cp[len] = 0;
196 }
197
198 return (kte);
199 }
200
201 #define KTE_TYPE(kte) ((kte)->kte_kth.ktr_type)
202 #define KTE_PID(kte) ((kte)->kte_kth.ktr_pid)
203 #define KTE_LID(kte) ((kte)->kte_kth.ktr_lid)
204 #define KTE_MATCH(kte, type, pid, lid) \
205 (KTE_TYPE(kte) == (type) && KTE_PID(kte) == (pid) && \
206 KTE_LID(kte) == (lid))
207
208 void
209 putpendq(struct ktr_entry *kte)
210 {
211
212 TAILQ_INSERT_TAIL(&ktependq, kte, kte_list);
213 }
214
215 void
216 flushpendq(struct ktr_entry *us)
217 {
218 struct ktr_entry *kte, *kte_next;
219 int pid = KTE_PID(us);
220
221 for (kte = TAILQ_FIRST(&ktependq); kte != NULL; kte = kte_next) {
222 kte_next = TAILQ_NEXT(kte, kte_list);
223 if (KTE_PID(kte) == pid) {
224 TAILQ_REMOVE(&ktependq, kte, kte_list);
225 free(kte);
226 }
227 }
228 }
229
230 struct ktr_entry *
231 getpendq(struct ktr_header *us, int type, struct kteq *kteq)
232 {
233 struct ktr_entry *kte, *kte_next;
234 int pid = us->ktr_pid, lid = us->ktr_lid;
235
236 if (kteq != NULL)
237 TAILQ_INIT(kteq);
238 for (kte = TAILQ_FIRST(&ktependq); kte != NULL; kte = kte_next) {
239 kte_next = TAILQ_NEXT(kte, kte_list);
240 if (KTE_MATCH(kte, type, pid, lid)) {
241 TAILQ_REMOVE(&ktependq, kte, kte_list);
242 if (kteq != NULL)
243 TAILQ_INSERT_TAIL(kteq, kte, kte_list);
244 else
245 break;
246 }
247 }
248
249 return (kteq ? TAILQ_FIRST(kteq) : kte);
250 }
251
252 int
253 dumprecord(int trpoints, FILE *fp)
254 {
255 struct ktr_entry *kte;
256 struct ktr_header *kth;
257
258 kte = getrecord(fp);
259 if (kte == NULL)
260 return (0);
261
262 kth = &kte->kte_kth;
263 if ((trpoints & (1 << kth->ktr_type)) == 0) {
264 free(kte);
265 goto out;
266 }
267
268 /* Update context to match currently processed record. */
269 ectx_sanify(kth->ktr_pid);
270
271 switch (kth->ktr_type) {
272 case KTR_SYSCALL:
273 ktrsyscall(kte);
274 break;
275 case KTR_SYSRET:
276 ktrsysret(kte);
277 break;
278 case KTR_NAMEI:
279 putpendq(kte);
280 break;
281 case KTR_GENIO:
282 putpendq(kte);
283 break;
284 case KTR_PSIG:
285 ktrpsig(kte);
286 break;
287 case KTR_CSW:
288 ktrcsw(kte);
289 break;
290 case KTR_EMUL:
291 ktremul(kte);
292 break;
293 default:
294 /*
295 * XXX: Other types added recently.
296 */
297 free(kte);
298 break;
299 }
300 newline();
301
302 out:
303 return (1);
304 }
305
306 void
307 dumpfile(const char *file, int fd, int trpoints)
308 {
309 FILE *fp;
310
311 if (file == NULL || *file == 0) {
312 if ((fp = fdopen(fd, "r")) == NULL)
313 err(EXIT_FAILURE, "fdopen(%d)", fd);
314 } else if (strcmp(file, "-") == 0)
315 fp = stdin;
316 else if ((fp = fopen(file, "r")) == NULL)
317 err(EXIT_FAILURE, "fopen: %s", file);
318
319 for (width = 0; dumprecord(trpoints, fp) != 0;)
320 if (tail)
321 (void)fflush(stdout);
322
323 newline();
324
325 /*
326 * XXX: Dump pending KTR_SYSCALL if any?
327 */
328 }
329
330 int
331 fread_tail(void *buf, int size, int num, FILE *fp)
332 {
333 int i;
334
335 while ((i = fread(buf, size, num, fp)) == 0 && tail) {
336 (void)sleep(1);
337 clearerr(fp);
338 }
339 return (i);
340 }
341
342 void
343 dumpheader(struct ktr_header *kth)
344 {
345 union timeholder {
346 struct timeval tv;
347 struct timespec ts;
348 };
349 static union timeholder prevtime;
350 union timeholder temp;
351
352 wprintf("%6d ", kth->ktr_pid);
353 if (kth->ktr_version > KTRFACv0)
354 wprintf("%6d ", kth->ktr_lid);
355 wprintf("%-8.*s ", MAXCOMLEN, kth->ktr_comm);
356 if (timestamp) {
357 if (timestamp == 2) {
358 if (kth->ktr_version == KTRFACv0) {
359 if (prevtime.tv.tv_sec == 0)
360 temp.tv.tv_sec = temp.tv.tv_usec = 0;
361 else
362 timersub(&kth->ktr_tv,
363 &prevtime.tv, &temp.tv);
364 prevtime.tv = kth->ktr_tv;
365 } else {
366 if (prevtime.ts.tv_sec == 0)
367 temp.ts.tv_sec = temp.ts.tv_nsec = 0;
368 else
369 timespecsub(&kth->ktr_time,
370 &prevtime.ts, &temp.ts);
371 prevtime.ts = kth->ktr_time;
372 }
373 } else {
374 if (kth->ktr_version == KTRFACv0)
375 temp.tv = kth->ktr_tv;
376 else
377 temp.ts = kth->ktr_time;
378 }
379 if (kth->ktr_version == KTRFACv0)
380 wprintf("%ld.%06ld ",
381 (long)temp.tv.tv_sec, (long)temp.tv.tv_usec);
382 else
383 wprintf("%ld.%09ld ",
384 (long)temp.ts.tv_sec, (long)temp.ts.tv_nsec);
385 }
386 }
387
388 void
389 ioctldecode(u_long cmd)
390 {
391 char dirbuf[4], *dir = dirbuf;
392
393 if (cmd & IOC_OUT)
394 *dir++ = 'W';
395 if (cmd & IOC_IN)
396 *dir++ = 'R';
397 *dir = '\0';
398
399 wprintf(decimal ? ", _IO%s('%c',%ld" : ", _IO%s('%c',%#lx",
400 dirbuf, (int) ((cmd >> 8) & 0xff), cmd & 0xff);
401 if ((cmd & IOC_VOID) == 0)
402 wprintf(decimal ? ",%ld)" : ",%#lx)",
403 (cmd >> 16) & 0xff);
404 else
405 wprintf(")");
406 }
407
408 void
409 nameiargprint(const char *prefix, struct ktr_header *kth,
410 register_t **ap, int *argsize)
411 {
412 struct ktr_entry *kte;
413
414 if (*argsize == 0)
415 errx(EXIT_FAILURE, "argument expected");
416 /*
417 * XXX: binary emulation mode.
418 */
419 kte = getpendq(kth, KTR_NAMEI, NULL);
420 if (kte == NULL)
421 argprint(prefix, ap, argsize);
422 else {
423 wprintf("%s", prefix);
424 nameiprint(&kte->kte_kth);
425 free(kte);
426 (*ap)++;
427 *argsize -= sizeof(register_t);
428 }
429 }
430
431 void
432 syscallnameprint(int code)
433 {
434
435 if (code >= cur_emul->nsysnames || code < 0)
436 wprintf("[%d]", code);
437 else
438 wprintf("%s", cur_emul->sysnames[code]);
439 }
440
441 void
442 argprint(const char *prefix, register_t **ap, int *argsize)
443 {
444
445 if (decimal)
446 wprintf("%s%ld", prefix, (long)**ap);
447 else
448 wprintf("%s%#lx", prefix, (long)**ap);
449 (*ap)++;
450 *argsize -= sizeof(register_t);
451 }
452
453 void
454 syscallprint(struct ktr_header *kth)
455 {
456 struct ktr_syscall *ktr = (struct ktr_syscall *)(kth + 1);
457 register_t *ap;
458 const char *s;
459 int argsize;
460
461 syscallnameprint(ktr->ktr_code);
462
463 /*
464 * Arguments processing.
465 */
466 argsize = ktr->ktr_argsize;
467 if (argsize == 0) {
468 wprintf("(");
469 goto noargument;
470 }
471
472 ap = (register_t *)(ktr + 1);
473 if (!fancy)
474 goto print_first;
475
476 switch (ktr->ktr_code) {
477 /*
478 * All these have a path as the first param.
479 * The order is same as syscalls.master.
480 */
481 case SYS_open:
482 case SYS_link:
483 case SYS_unlink:
484 case SYS_chdir:
485 case SYS_mknod:
486 case SYS_chmod:
487 case SYS_chown:
488 case SYS_unmount:
489 case SYS_access:
490 case SYS_chflags:
491 case SYS_acct:
492 case SYS_revoke:
493 case SYS_symlink:
494 case SYS_readlink:
495 case SYS_execve:
496 case SYS_chroot:
497 case SYS_rename:
498 case SYS_mkfifo:
499 case SYS_mkdir:
500 case SYS_rmdir:
501 case SYS_utimes:
502 case SYS_quotactl:
503 case SYS_statvfs1:
504 case SYS_compat_30_getfh:
505 case SYS_pathconf:
506 case SYS_truncate:
507 case SYS_undelete:
508 case SYS___posix_rename:
509 case SYS_lchmod:
510 case SYS_lchown:
511 case SYS_lutimes:
512 case SYS___stat30:
513 case SYS___lstat30:
514 case SYS___posix_chown:
515 case SYS___posix_lchown:
516 case SYS_lchflags:
517 case SYS___getfh30:
518 nameiargprint("(", kth, &ap, &argsize);
519
520 /*
521 * 2nd argument is also pathname.
522 */
523 switch (ktr->ktr_code) {
524 case SYS_link:
525 case SYS_rename:
526 case SYS___posix_rename:
527 nameiargprint(", ", kth, &ap, &argsize);
528 break;
529 }
530 break;
531
532 case SYS_compat_16___sigaction14 :
533 wprintf("(%s", signals[(int)*ap].name);
534 ap++;
535 argsize -= sizeof(register_t);
536 break;
537
538 case SYS_ioctl :
539 argprint("(", &ap, &argsize);
540 if ((s = ioctlname(*ap)) != NULL)
541 wprintf(", %s", s);
542 else
543 ioctldecode(*ap);
544 ap++;
545 argsize -= sizeof(register_t);
546 break;
547
548 case SYS_ptrace :
549 if ((long)*ap >= 0 &&
550 *ap < sizeof(ptrace_ops) / sizeof(ptrace_ops[0]))
551 wprintf("(%s", ptrace_ops[*ap]);
552 else
553 wprintf("(%ld", (long)*ap);
554 ap++;
555 argsize -= sizeof(register_t);
556 break;
557
558 default:
559 print_first:
560 argprint("(", &ap, &argsize);
561 break;
562 }
563
564 /* Print rest of argument. */
565 while (argsize > 0)
566 argprint(", ", &ap, &argsize);
567
568 noargument:
569 wprintf(")");
570 }
571
572 void
573 ktrsyscall(struct ktr_entry *kte)
574 {
575 struct ktr_header *kth = &kte->kte_kth;
576 struct ktr_syscall *ktr = (struct ktr_syscall *)(kth + 1);
577
578 switch (ktr->ktr_code) {
579 case SYS_exit:
580 dumpheader(kth);
581 syscallprint(kth);
582 break;
583 default:
584 putpendq(kte);
585 return;
586 }
587
588 free(kte);
589 }
590
591 void
592 sysretprint(struct ktr_header *kth)
593 {
594 struct ktr_sysret *ktr = (struct ktr_sysret *)(kth + 1);
595 register_t ret = ktr->ktr_retval;
596 int error = ktr->ktr_error;
597
598 indent(50);
599 if (error == EJUSTRETURN)
600 wprintf(" JUSTRETURN");
601 else if (error == ERESTART)
602 wprintf(" RESTART");
603 else if (error) {
604 wprintf(" Err#%d", error);
605 if (error < MAXERRNOS && error >= -2)
606 wprintf(" %s", errnos[error].name);
607 } else
608 switch (ktr->ktr_code) {
609 case SYS_mmap:
610 wprintf(" = %p", (long)ret);
611 break;
612 default:
613 wprintf(" = %ld", (long)ret);
614 if (kth->ktr_len > offsetof(struct ktr_sysret,
615 ktr_retval_1) && ktr->ktr_retval_1 != 0)
616 wprintf(", %ld", (long)ktr->ktr_retval_1);
617 break;
618 }
619 }
620
621 void
622 ktrsysret(struct ktr_entry *kte)
623 {
624 struct ktr_header *kth = &kte->kte_kth;
625 struct ktr_sysret *ktr = (struct ktr_sysret *)(kth + 1);
626 struct ktr_entry *genio;
627 struct ktr_entry *syscall_ent;
628
629 dumpheader(kth);
630
631 /* Print syscall name and arguments. */
632 syscall_ent = getpendq(kth, KTR_SYSCALL, NULL);
633 if (syscall_ent == NULL) {
634 /*
635 * Possibilly a child of fork/vfork, or tracing of
636 * process started during system call.
637 */
638 syscallnameprint(ktr->ktr_code);
639 } else {
640 syscallprint(&syscall_ent->kte_kth);
641 free(syscall_ent);
642 }
643
644 /* Print return value and an error if any. */
645 sysretprint(kth);
646
647 genio = getpendq(kth, KTR_GENIO, NULL);
648 if (genio != NULL) {
649 genioprint(&genio->kte_kth);
650 free(genio);
651 }
652
653 #if 0 /* Why? */
654 flushpendq(kte);
655 #endif
656 free(kte);
657 }
658
659 void
660 nameiprint(struct ktr_header *kth)
661 {
662
663 wprintf("\"%.*s\"", kth->ktr_len, (char *)(kth + 1));
664 }
665
666 #ifdef notused
667 void
668 ktrnamei(struct ktr_entry *kte)
669 {
670 struct ktr_header *kth = &kte->kte_kth;
671
672 dumpheader(kth);
673 wprintf("namei(");
674 nameiprint(kth);
675 wprintf(")");
676
677 free(kte);
678 }
679 #endif
680
681 void
682 ktremul(struct ktr_entry *kte)
683 {
684 struct ktr_header *kth = &kte->kte_kth;
685 char *emul = (char *)(kth + 1);
686
687 dumpheader(kth);
688 wprintf("emul(%s)", emul);
689 setemul(emul, kth->ktr_pid, 1);
690
691 free(kte);
692 }
693
694 void
695 genioprint(struct ktr_header *kth)
696 {
697 struct ktr_genio *ktr = (struct ktr_genio *)(kth + 1);
698 static int screenwidth = 0;
699 int datalen = kth->ktr_len - sizeof(struct ktr_genio);
700 /*
701 * Need to be unsigned type so that positive value is passed
702 * to vis(), which will call isgraph().
703 */
704 unsigned char *dp = (unsigned char *)(ktr + 1);
705 int w;
706 char visbuf[5];
707
708 if (screenwidth == 0) {
709 struct winsize ws;
710
711 if (fancy && ioctl(fileno(stderr), TIOCGWINSZ, &ws) != -1 &&
712 ws.ws_col > 8)
713 screenwidth = ws.ws_col;
714 else
715 screenwidth = 80;
716 }
717
718 if (maxdata && datalen > maxdata)
719 datalen = maxdata;
720 newline();
721 wprintf(" \"");
722 for (; datalen > 0; datalen--, dp++) {
723 (void) vis(visbuf, *dp, VIS_NL|VIS_TAB|VIS_CSTYLE,
724 /* We put NUL at the end of buffer when reading */
725 *(dp + 1));
726 visbuf[4] = '\0';
727 w = strlen(visbuf);
728 if (width + w + 2 >= screenwidth)
729 break;
730 wprintf("%s", visbuf);
731 if (width + 2 >= screenwidth)
732 break;
733 }
734 wprintf("\"");
735 }
736
737 #ifdef notused
738 void
739 ktrgenio(struct ktr_entry *kte)
740 {
741 struct ktr_header *kth = &kte->kte_kth;
742 struct ktr_genio *ktr = (struct ktr_genio *)(kth + 1);
743
744 dumpheader(kth);
745 wprintf("genio fd %d %s",
746 ktr->ktr_fd, ktr->ktr_rw ? "write" : "read");
747 genioprint(kth);
748
749 free(kte);
750 }
751 #endif
752
753 void
754 ktrpsig(struct ktr_entry *kte)
755 {
756 struct ktr_header *kth = &kte->kte_kth;
757 struct ktr_psig *psig = (struct ktr_psig *)(kth + 1);
758
759 dumpheader(kth);
760 wprintf("SIG%s ", sys_signame[psig->signo]);
761 if (psig->action == SIG_DFL)
762 wprintf("SIG_DFL");
763 else {
764 wprintf("caught handler=0x%lx mask=0x%lx code=0x%x",
765 (u_long)psig->action, (unsigned long)psig->mask.__bits[0],
766 psig->code);
767 }
768
769 free(kte);
770 }
771
772 void
773 ktrcsw(struct ktr_entry *kte)
774 {
775 struct ktr_header *kth = &kte->kte_kth;
776 struct ktr_csw *cs = (struct ktr_csw *)(kth + 1);
777
778 dumpheader(kth);
779 wprintf("%s %s", cs->out ? "stop" : "resume",
780 cs->user ? "user" : "kernel");
781
782 free(kte);
783 }
784