savecore.c revision 1.64 1 /* $NetBSD: savecore.c,v 1.64 2004/07/14 07:26:12 tls Exp $ */
2
3 /*-
4 * Copyright (c) 1986, 1992, 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) 1986, 1992, 1993\n\
35 The Regents of the University of California. All rights reserved.\n");
36 #endif /* not lint */
37
38 #ifndef lint
39 #if 0
40 static char sccsid[] = "@(#)savecore.c 8.5 (Berkeley) 4/28/95";
41 #else
42 __RCSID("$NetBSD: savecore.c,v 1.64 2004/07/14 07:26:12 tls Exp $");
43 #endif
44 #endif /* not lint */
45
46 #include <sys/param.h>
47 #include <sys/mount.h>
48 #include <sys/msgbuf.h>
49 #include <sys/syslog.h>
50 #include <sys/time.h>
51
52 #include <dirent.h>
53 #include <errno.h>
54 #include <fcntl.h>
55 #include <nlist.h>
56 #include <paths.h>
57 #include <stddef.h>
58 #include <stdio.h>
59 #include <stdlib.h>
60 #include <string.h>
61 #include <time.h>
62 #include <tzfile.h>
63 #include <unistd.h>
64 #include <util.h>
65 #include <limits.h>
66 #include <kvm.h>
67
68 extern FILE *zopen(const char *fname, const char *mode);
69
70 #define KREAD(kd, addr, p)\
71 (kvm_read(kd, addr, (char *)(p), sizeof(*(p))) != sizeof(*(p)))
72
73 struct nlist current_nl[] = { /* Namelist for currently running system. */
74 #define X_DUMPDEV 0
75 { "_dumpdev" },
76 #define X_DUMPLO 1
77 { "_dumplo" },
78 #define X_TIME 2
79 { "_time" },
80 #define X_DUMPSIZE 3
81 { "_dumpsize" },
82 #define X_VERSION 4
83 { "_version" },
84 #define X_DUMPMAG 5
85 { "_dumpmag" },
86 #define X_PANICSTR 6
87 { "_panicstr" },
88 #define X_PANICSTART 7
89 { "_panicstart" },
90 #define X_PANICEND 8
91 { "_panicend" },
92 #define X_MSGBUF 9
93 { "_msgbufp" },
94 { NULL },
95 };
96 int cursyms[] = { X_DUMPDEV, X_DUMPLO, X_VERSION, X_DUMPMAG, -1 };
97 int dumpsyms[] = { X_TIME, X_DUMPSIZE, X_VERSION, X_PANICSTR, X_DUMPMAG, -1 };
98
99 struct nlist dump_nl[] = { /* Name list for dumped system. */
100 { "_dumpdev" }, /* Entries MUST be the same as */
101 { "_dumplo" }, /* those in current_nl[]. */
102 { "_time" },
103 { "_dumpsize" },
104 { "_version" },
105 { "_dumpmag" },
106 { "_panicstr" },
107 { "_panicstart" },
108 { "_panicend" },
109 { "_msgbufp" },
110 { NULL },
111 };
112
113 /* Types match kernel declarations. */
114 off_t dumplo; /* where dump starts on dumpdev */
115 u_int32_t dumpmag; /* magic number in dump */
116 int dumpsize; /* amount of memory dumped */
117 off_t dumpbytes; /* in bytes */
118
119 const char *kernel; /* name of used kernel */
120 char *dirname; /* directory to save dumps in */
121 char *ddname; /* name of dump device */
122 dev_t dumpdev; /* dump device */
123 int dumpfd; /* read/write descriptor on block dev */
124 kvm_t *kd_dump; /* kvm descriptor on block dev */
125 time_t now; /* current date */
126 char panic_mesg[1024];
127 long panicstr;
128 char vers[1024];
129 char gzmode[3];
130
131 static int clear, compress, force, verbose; /* flags */
132
133 void check_kmem(void);
134 int check_space(void);
135 void clear_dump(void);
136 int Create(char *, int);
137 int dump_exists(void);
138 char *find_dev(dev_t, int);
139 int get_crashtime(void);
140 void kmem_setup(void);
141 void Lseek(int, off_t, int);
142 int main(int, char *[]);
143 int Open(const char *, int rw);
144 char *rawname(char *s);
145 void save_core(void);
146 void usage(void);
147 void Write(int, void *, int);
148
149 int
150 main(int argc, char *argv[])
151 {
152 int ch, level;
153 char *ep;
154
155 dirname = NULL;
156 kernel = NULL;
157 level = 1; /* default to fastest gzip compression */
158 gzmode[0] = 'w';
159
160 openlog("savecore", LOG_PERROR, LOG_DAEMON);
161
162 while ((ch = getopt(argc, argv, "cdfN:vzZ:")) != -1)
163 switch(ch) {
164 case 'c':
165 clear = 1;
166 break;
167 case 'd': /* Not documented. */
168 case 'v':
169 verbose = 1;
170 break;
171 case 'f':
172 force = 1;
173 break;
174 case 'N':
175 kernel = optarg;
176 break;
177 case 'z':
178 compress = 1;
179 break;
180 case 'Z':
181 level = (int)strtol(optarg, &ep, 10);
182 if (level < 0 || level > 9) {
183 (void)syslog(LOG_ERR, "invalid compression %s",
184 optarg);
185 usage();
186 }
187 break;
188 case '?':
189 default:
190 usage();
191 }
192 argc -= optind;
193 argv += optind;
194
195 if (argc != (clear ? 0 : 1))
196 usage();
197
198 gzmode[1] = level + '0';
199 if (!clear)
200 dirname = argv[0];
201
202 if (kernel == NULL) {
203 kernel = getbootfile();
204 }
205
206 (void)time(&now);
207 kmem_setup();
208
209 if (clear) {
210 clear_dump();
211 exit(0);
212 }
213
214 if (!dump_exists() && !force)
215 exit(1);
216
217 check_kmem();
218
219 if (panicstr)
220 syslog(LOG_ALERT, "reboot after panic: %s", panic_mesg);
221 else
222 syslog(LOG_ALERT, "reboot");
223
224 if ((!get_crashtime() || !check_space()) && !force)
225 exit(1);
226
227 save_core();
228
229 clear_dump();
230 exit(0);
231 }
232
233 void
234 kmem_setup(void)
235 {
236 kvm_t *kd_kern;
237 char errbuf[_POSIX2_LINE_MAX];
238 int i, hdrsz;
239
240 /*
241 * Some names we need for the currently running system, others for
242 * the system that was running when the dump was made. The values
243 * obtained from the current system are used to look for things in
244 * /dev/kmem that cannot be found in the kernel namelist, but are
245 * presumed to be the same (since the disk partitions are probably
246 * the same!)
247 */
248 kd_kern = kvm_openfiles(kernel, NULL, NULL, O_RDONLY, errbuf);
249 if (kd_kern == NULL) {
250 syslog(LOG_ERR, "%s: kvm_openfiles: %s", kernel, errbuf);
251 exit(1);
252 }
253 if (kvm_nlist(kd_kern, current_nl) == -1)
254 syslog(LOG_ERR, "%s: kvm_nlist: %s", kernel,
255 kvm_geterr(kd_kern));
256
257 for (i = 0; cursyms[i] != -1; i++)
258 if (current_nl[cursyms[i]].n_value == 0) {
259 syslog(LOG_ERR, "%s: %s not in namelist",
260 kernel, current_nl[cursyms[i]].n_name);
261 exit(1);
262 }
263
264 if (KREAD(kd_kern, current_nl[X_DUMPDEV].n_value, &dumpdev) != 0) {
265 if (verbose)
266 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_kern));
267 exit(1);
268 }
269 if (dumpdev == NODEV) {
270 syslog(LOG_WARNING, "no core dump (no dumpdev)");
271 exit(1);
272 }
273 {
274 long l_dumplo;
275
276 if (KREAD(kd_kern, current_nl[X_DUMPLO].n_value, &l_dumplo) != 0) {
277 if (verbose)
278 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_kern));
279 exit(1);
280 }
281 if (l_dumplo == -1) {
282 syslog(LOG_WARNING, "no core dump (invalid dumplo)");
283 exit(1);
284 }
285 dumplo = DEV_BSIZE * (off_t) l_dumplo;
286 }
287
288 if (verbose)
289 (void)printf("dumplo = %lld (%ld * %ld)\n",
290 (long long)dumplo, (long)(dumplo / DEV_BSIZE), (long)DEV_BSIZE);
291 if (KREAD(kd_kern, current_nl[X_DUMPMAG].n_value, &dumpmag) != 0) {
292 if (verbose)
293 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_kern));
294 exit(1);
295 }
296
297 (void)kvm_read(kd_kern, current_nl[X_VERSION].n_value, vers,
298 sizeof(vers));
299 vers[sizeof(vers) - 1] = '\0';
300
301 ddname = find_dev(dumpdev, S_IFBLK);
302 dumpfd = Open(ddname, O_RDWR);
303
304 kd_dump = kvm_openfiles(kernel, ddname, NULL, O_RDWR, errbuf);
305 if (kd_dump == NULL) {
306 syslog(LOG_ERR, "%s: kvm_openfiles: %s", kernel, errbuf);
307 exit(1);
308 }
309
310 if (kvm_nlist(kd_dump, dump_nl) == -1)
311 syslog(LOG_ERR, "%s: kvm_nlist: %s", kernel,
312 kvm_geterr(kd_dump));
313
314 for (i = 0; dumpsyms[i] != -1; i++)
315 if (dump_nl[dumpsyms[i]].n_value == 0) {
316 syslog(LOG_ERR, "%s: %s not in namelist",
317 kernel, dump_nl[dumpsyms[i]].n_name);
318 exit(1);
319 }
320 hdrsz = kvm_dump_mkheader(kd_dump, dumplo);
321
322 /*
323 * If 'hdrsz' == 0, kvm_dump_mkheader() failed on the magic-number
324 * checks, ergo no dump is present...
325 */
326 if (hdrsz == 0) {
327 syslog(LOG_WARNING, "no core dump");
328 exit(1);
329 }
330 if (hdrsz == -1) {
331 syslog(LOG_ERR, "%s: kvm_dump_mkheader: %s", kernel,
332 kvm_geterr(kd_dump));
333 exit(1);
334 }
335 dumplo += hdrsz;
336 kvm_close(kd_kern);
337 }
338
339 void
340 check_kmem(void)
341 {
342 char *cp, *bufdata;
343 struct kern_msgbuf msgbuf, *bufp;
344 long panicloc, panicstart, panicend;
345 char core_vers[1024];
346
347 (void)kvm_read(kd_dump, dump_nl[X_VERSION].n_value, core_vers,
348 sizeof(core_vers));
349 core_vers[sizeof(core_vers) - 1] = '\0';
350
351 if (strcmp(vers, core_vers) != 0)
352 syslog(LOG_WARNING,
353 "warning: %s version mismatch:\n\t%s\nand\t%s\n",
354 kernel, vers, core_vers);
355
356 panicstart = panicend = 0;
357 if (KREAD(kd_dump, dump_nl[X_PANICSTART].n_value, &panicstart) != 0) {
358 if (verbose)
359 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump));
360 goto nomsguf;
361 }
362 if (KREAD(kd_dump, dump_nl[X_PANICEND].n_value, &panicend) != 0) {
363 if (verbose)
364 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump));
365 goto nomsguf;
366 }
367 if (panicstart != 0 && panicend != 0) {
368 if (KREAD(kd_dump, dump_nl[X_MSGBUF].n_value, &bufp)) {
369 if (verbose)
370 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump));
371 goto nomsguf;
372 }
373 if (kvm_read(kd_dump, (long)bufp, &msgbuf,
374 offsetof(struct kern_msgbuf, msg_bufc)) !=
375 offsetof(struct kern_msgbuf, msg_bufc)) {
376 if (verbose)
377 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump));
378 goto nomsguf;
379 }
380 if (msgbuf.msg_magic != MSG_MAGIC) {
381 if (verbose)
382 syslog(LOG_WARNING, "msgbuf magic incorrect");
383 goto nomsguf;
384 }
385 bufdata = malloc(msgbuf.msg_bufs);
386 if (bufdata == NULL) {
387 if (verbose)
388 syslog(LOG_WARNING, "couldn't allocate space for msgbuf data");
389 goto nomsguf;
390 }
391 if (kvm_read(kd_dump, (long)&bufp->msg_bufc, bufdata,
392 msgbuf.msg_bufs) != msgbuf.msg_bufs) {
393 if (verbose)
394 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump));
395 goto nomsguf;
396 }
397 cp = panic_mesg;
398 while (panicstart != panicend && cp < &panic_mesg[sizeof(panic_mesg)-1]) {
399 *cp++ = bufdata[panicstart];
400 panicstart++;
401 if (panicstart >= msgbuf.msg_bufs)
402 panicstart = 0;
403 }
404 /* Don't end in a new-line */
405 cp = &panic_mesg[strlen(panic_mesg)] - 1;
406 if (*cp == '\n')
407 *cp = '\0';
408 panic_mesg[sizeof(panic_mesg) - 1] = '\0';
409
410 panicstr = 1; /* anything not zero */
411 return;
412 }
413 nomsguf:
414 if (KREAD(kd_dump, dump_nl[X_PANICSTR].n_value, &panicstr) != 0) {
415 if (verbose)
416 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump));
417 return;
418 }
419 if (panicstr) {
420 cp = panic_mesg;
421 panicloc = panicstr;
422 do {
423 if (KREAD(kd_dump, panicloc, cp) != 0) {
424 if (verbose)
425 syslog(LOG_WARNING, "kvm_read: %s",
426 kvm_geterr(kd_dump));
427 break;
428 }
429 panicloc++;
430 } while (*cp++ && cp < &panic_mesg[sizeof(panic_mesg)-1]);
431 panic_mesg[sizeof(panic_mesg) - 1] = '\0';
432 }
433 }
434
435 int
436 dump_exists(void)
437 {
438 u_int32_t newdumpmag;
439
440 if (KREAD(kd_dump, dump_nl[X_DUMPMAG].n_value, &newdumpmag) != 0) {
441 if (verbose)
442 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump));
443 return (0);
444 }
445
446 /* Read the dump size. */
447 if (KREAD(kd_dump, dump_nl[X_DUMPSIZE].n_value, &dumpsize) != 0) {
448 if (verbose)
449 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump));
450 return (0);
451 }
452 dumpbytes = (off_t)dumpsize * getpagesize();
453
454 /*
455 * Return zero if core dump doesn't seem to be there, and note
456 * it for syslog. This check and return happens after the dump size
457 * is read, so dumpsize is whether or not the core is valid (for -f).
458 */
459 if (newdumpmag != dumpmag) {
460 if (verbose)
461 syslog(LOG_WARNING,
462 "magic number mismatch (0x%x != 0x%x)",
463 newdumpmag, dumpmag);
464 syslog(LOG_WARNING, "no core dump");
465 return (0);
466 }
467 return (1);
468 }
469
470 void
471 clear_dump(void)
472 {
473 if (kvm_dump_inval(kd_dump) == -1)
474 syslog(LOG_ERR, "%s: kvm_clear_dump: %s", ddname,
475 kvm_geterr(kd_dump));
476
477 }
478
479 char buf[1024 * 1024];
480
481 void
482 save_core(void)
483 {
484 FILE *fp;
485 int bounds, ifd, nr, nw, ofd;
486 char *rawp, path[MAXPATHLEN];
487
488 ofd = -1;
489 /*
490 * Get the current number and update the bounds file. Do the update
491 * now, because may fail later and don't want to overwrite anything.
492 */
493 umask(066);
494 (void)snprintf(path, sizeof(path), "%s/bounds", dirname);
495 if ((fp = fopen(path, "r")) == NULL)
496 goto err1;
497 if (fgets(buf, sizeof(buf), fp) == NULL) {
498 if (ferror(fp))
499 err1: syslog(LOG_WARNING, "%s: %m", path);
500 bounds = 0;
501 } else
502 bounds = atoi(buf);
503 if (fp != NULL)
504 (void)fclose(fp);
505 if ((fp = fopen(path, "w")) == NULL)
506 syslog(LOG_ERR, "%s: %m", path);
507 else {
508 (void)fprintf(fp, "%d\n", bounds + 1);
509 (void)fclose(fp);
510 }
511
512 /* Create the core file. */
513 (void)snprintf(path, sizeof(path), "%s/netbsd.%d.core%s",
514 dirname, bounds, compress ? ".gz" : "");
515 if (compress) {
516 if ((fp = zopen(path, gzmode)) == NULL) {
517 syslog(LOG_ERR, "%s: %m", path);
518 exit(1);
519 }
520 } else {
521 ofd = Create(path, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
522 fp = fdopen(ofd, "w");
523 if (fp == NULL) {
524 syslog(LOG_ERR, "%s: fdopen: %m", path);
525 exit(1);
526 }
527 }
528
529 /* Open the raw device. */
530 rawp = rawname(ddname);
531 if ((ifd = open(rawp, O_RDONLY)) == -1) {
532 syslog(LOG_WARNING, "%s: %m; using block device", rawp);
533 ifd = dumpfd;
534 }
535
536 /* Seek to the start of the core. */
537 Lseek(ifd, dumplo, SEEK_SET);
538
539 if (kvm_dump_wrtheader(kd_dump, fp, (int32_t)dumpbytes) == -1) {
540 syslog(LOG_ERR, "kvm_dump_wrtheader: %s : %s", path,
541 kvm_geterr(kd_dump));
542 exit(1);
543 }
544
545 /* Copy the core file. */
546 syslog(LOG_NOTICE, "writing %score to %s",
547 compress ? "compressed " : "", path);
548 for (; dumpbytes > (off_t)0; dumpbytes -= (off_t)nr) {
549 char nbuf[7];
550 humanize_number(nbuf, 7, dumpbytes, "", HN_AUTOSCALE, 0);
551 (void)printf("%7s\r", nbuf);
552 (void)fflush(stdout);
553 nr = read(ifd, buf, MIN(dumpbytes, sizeof(buf)));
554 if (nr <= 0) {
555 if (nr == 0)
556 syslog(LOG_WARNING,
557 "WARNING: EOF on dump device");
558 else
559 syslog(LOG_ERR, "%s: %m", rawp);
560 goto err2;
561 }
562 nw = fwrite(buf, 1, nr, fp);
563 if (nw != nr) {
564 syslog(LOG_ERR, "%s: %s",
565 path, strerror(nw == 0 ? EIO : errno));
566 err2: syslog(LOG_WARNING,
567 "WARNING: core may be incomplete");
568 (void)printf("\n");
569 exit(1);
570 }
571 }
572 (void)close(ifd);
573 (void)fclose(fp);
574
575 /* Copy the kernel. */
576 ifd = Open(kernel, O_RDONLY);
577 (void)snprintf(path, sizeof(path), "%s/netbsd.%d%s",
578 dirname, bounds, compress ? ".gz" : "");
579 if (compress) {
580 if ((fp = zopen(path, gzmode)) == NULL) {
581 syslog(LOG_ERR, "%s: %m", path);
582 exit(1);
583 }
584 } else
585 ofd = Create(path, S_IRUSR | S_IWUSR);
586 syslog(LOG_NOTICE, "writing %skernel to %s",
587 compress ? "compressed " : "", path);
588 while ((nr = read(ifd, buf, sizeof(buf))) > 0) {
589 if (compress)
590 nw = fwrite(buf, 1, nr, fp);
591 else
592 nw = write(ofd, buf, nr);
593 if (nw != nr) {
594 syslog(LOG_ERR, "%s: %s",
595 path, strerror(nw == 0 ? EIO : errno));
596 syslog(LOG_WARNING,
597 "WARNING: kernel may be incomplete");
598 exit(1);
599 }
600 }
601 if (nr < 0) {
602 syslog(LOG_ERR, "%s: %m", kernel);
603 syslog(LOG_WARNING, "WARNING: kernel may be incomplete");
604 exit(1);
605 }
606 if (compress)
607 (void)fclose(fp);
608 else
609 (void)close(ofd);
610 }
611
612 char *
613 find_dev(dev_t dev, int type)
614 {
615 DIR *dfd;
616 struct dirent *dir;
617 struct stat sb;
618 char *dp, device[MAXPATHLEN + 1], *p;
619 size_t l;
620
621 if ((dfd = opendir(_PATH_DEV)) == NULL) {
622 syslog(LOG_ERR, "%s: %m", _PATH_DEV);
623 exit(1);
624 }
625 strlcpy(device, _PATH_DEV, sizeof(device));
626 p = &device[strlen(device)];
627 l = sizeof(device) - strlen(device);
628 while ((dir = readdir(dfd))) {
629 strlcpy(p, dir->d_name, l);
630 if (lstat(device, &sb)) {
631 syslog(LOG_ERR, "%s: %m", device);
632 continue;
633 }
634 if ((sb.st_mode & S_IFMT) != type)
635 continue;
636 if (dev == sb.st_rdev) {
637 closedir(dfd);
638 if ((dp = strdup(device)) == NULL) {
639 syslog(LOG_ERR, "%m");
640 exit(1);
641 }
642 return (dp);
643 }
644 }
645 closedir(dfd);
646 syslog(LOG_ERR, "can't find device %d/%d", major(dev), minor(dev));
647 exit(1);
648 }
649
650 char *
651 rawname(char *s)
652 {
653 char *sl;
654 char name[MAXPATHLEN];
655
656 if ((sl = strrchr(s, '/')) == NULL || sl[1] == '0') {
657 syslog(LOG_ERR,
658 "can't make raw dump device name from %s", s);
659 return (s);
660 }
661 (void)snprintf(name, sizeof(name), "%.*s/r%s", (int)(sl - s), s,
662 sl + 1);
663 if ((sl = strdup(name)) == NULL) {
664 syslog(LOG_ERR, "%m");
665 exit(1);
666 }
667 return (sl);
668 }
669
670 int
671 get_crashtime(void)
672 {
673 struct timeval dtime;
674 time_t dumptime; /* Time the dump was taken. */
675
676 if (KREAD(kd_dump, dump_nl[X_TIME].n_value, &dtime) != 0) {
677 if (verbose)
678 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump));
679 return (0);
680 }
681 dumptime = dtime.tv_sec;
682 if (dumptime == 0) {
683 if (verbose)
684 syslog(LOG_ERR, "dump time is zero");
685 return (0);
686 }
687 (void)printf("savecore: system went down at %s", ctime(&dumptime));
688 #define LEEWAY (60 * SECSPERDAY)
689 if (dumptime < now - LEEWAY || dumptime > now + LEEWAY) {
690 (void)printf("dump time is unreasonable\n");
691 return (0);
692 }
693 return (1);
694 }
695
696 int
697 check_space(void)
698 {
699 FILE *fp;
700 off_t minfree, spacefree, kernelsize, needed;
701 struct stat st;
702 struct statvfs fsbuf;
703 char mbuf[100], path[MAXPATHLEN];
704
705 #ifdef __GNUC__
706 (void) &minfree;
707 #endif
708
709 if (stat(kernel, &st) < 0) {
710 syslog(LOG_ERR, "%s: %m", kernel);
711 exit(1);
712 }
713 kernelsize = st.st_blocks * S_BLKSIZE;
714 if (statvfs(dirname, &fsbuf) < 0) {
715 syslog(LOG_ERR, "%s: %m", dirname);
716 exit(1);
717 }
718 spacefree = fsbuf.f_bavail;
719 spacefree *= fsbuf.f_frsize;
720 spacefree /= 1024;
721
722 (void)snprintf(path, sizeof(path), "%s/minfree", dirname);
723 if ((fp = fopen(path, "r")) == NULL)
724 minfree = 0;
725 else {
726 if (fgets(mbuf, sizeof(mbuf), fp) == NULL)
727 minfree = 0;
728 else
729 minfree = atoi(mbuf);
730 (void)fclose(fp);
731 }
732
733 needed = (dumpbytes + kernelsize) / 1024;
734 if (minfree > 0 && spacefree - needed < minfree) {
735 syslog(LOG_WARNING,
736 "no dump, not enough free space in %s", dirname);
737 return (0);
738 }
739 if (spacefree - needed < minfree)
740 syslog(LOG_WARNING,
741 "dump performed, but free space threshold crossed");
742 return (1);
743 }
744
745 int
746 Open(const char *name, int rw)
747 {
748 int fd;
749
750 if ((fd = open(name, rw, 0)) < 0) {
751 syslog(LOG_ERR, "%s: %m", name);
752 exit(1);
753 }
754 return (fd);
755 }
756
757 void
758 Lseek(int fd, off_t off, int flag)
759 {
760 off_t ret;
761
762 ret = lseek(fd, off, flag);
763 if (ret == -1) {
764 syslog(LOG_ERR, "lseek: %m");
765 exit(1);
766 }
767 }
768
769 int
770 Create(char *file, int mode)
771 {
772 int fd;
773
774 fd = open(file, O_WRONLY | O_CREAT | O_TRUNC, mode);
775 if (fd < 0) {
776 syslog(LOG_ERR, "%s: %m", file);
777 exit(1);
778 }
779 return (fd);
780 }
781
782 void
783 Write(int fd, void *bp, int size)
784 {
785 int n;
786
787 if ((n = write(fd, bp, size)) < size) {
788 syslog(LOG_ERR, "write: %s", strerror(n == -1 ? errno : EIO));
789 exit(1);
790 }
791 }
792
793 void
794 usage(void)
795 {
796 (void)syslog(LOG_ERR,
797 "usage: savecore [-cfvz] [-N system] [-Z level] directory");
798 exit(1);
799 }
800