Initial import, 0.1 + pk 0.2.4-B1
[unix-history] / sbin / savecore / savecore.c
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15637ed4
RG
1/*
2 * Copyright (c) 1980, 1986, 1989 The Regents of the University of California.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#ifndef lint
35char copyright[] =
36"@(#) Copyright (c) 1980, 1986, 1989 The Regents of the University of California.\n\
37 All rights reserved.\n";
38#endif /* not lint */
39
40#ifndef lint
41static char sccsid[] = "@(#)savecore.c 5.26 (Berkeley) 4/8/91";
42#endif /* not lint */
43
44#include <sys/param.h>
45#include <sys/mount.h>
46#include <sys/stat.h>
47#include <sys/time.h>
48#include <sys/file.h>
49#include <sys/syslog.h>
50#include <dirent.h>
51#include <stdio.h>
52#include <nlist.h>
53#include <paths.h>
54
55#define DAY (60L*60L*24L)
56#define LEEWAY (3*DAY)
57
58#define eq(a,b) (!strcmp(a,b))
59#ifdef vax
60#define ok(number) ((number)&0x7fffffff)
61#else
62#ifdef tahoe
63#define ok(number) ((number)&~0xc0000000)
64#else
65#ifdef i386
66#define ok(number) ((number)&~0xfe000000)
67#else
68#define ok(number) (number)
69#endif
70#endif
71#endif
72
73struct 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_PANICSTR 5
85 { "_panicstr" },
86#define X_DUMPMAG 6
87 { "_dumpmag" },
88 { "" },
89};
90
91struct nlist dump_nl[] = { /* name list for dumped system */
92 { "_dumpdev" }, /* entries MUST be the same as */
93 { "_dumplo" }, /* those in current_nl[] */
94 { "_time" },
95 { "_dumpsize" },
96 { "_version" },
97 { "_panicstr" },
98 { "_dumpmag" },
99 { "" },
100};
101
102char *system;
103char *dirname; /* directory to save dumps in */
104char *ddname; /* name of dump device */
105int dumpfd; /* read/write descriptor on block dev */
106char *find_dev();
107dev_t dumpdev; /* dump device */
108time_t dumptime; /* time the dump was taken */
109int dumplo; /* where dump starts on dumpdev */
110int dumpsize; /* amount of memory dumped */
111int dumpmag; /* magic number in dump */
112time_t now; /* current date */
113char *path();
114char *malloc();
115char *ctime();
116char vers[80];
117char core_vers[80];
118char panic_mesg[80];
119int panicstr;
120off_t lseek();
121off_t Lseek();
122int verbose;
123int force;
124int clear;
125extern int errno;
126
127main(argc, argv)
128 char **argv;
129 int argc;
130{
131 extern char *optarg;
132 extern int optind;
133 int ch;
134 char *cp;
135
136 while ((ch = getopt(argc, argv, "cdfv")) != EOF)
137 switch(ch) {
138 case 'c':
139 clear = 1;
140 break;
141 case 'd': /* not documented */
142 case 'v':
143 verbose = 1;
144 break;
145 case 'f':
146 force = 1;
147 break;
148 case '?':
149 default:
150 usage();
151 }
152 argc -= optind;
153 argv += optind;
154
155 /* This is wrong, but I want "savecore -c" to work. */
156 if (!clear) {
157 if (argc != 1 && argc != 2)
158 usage();
159 dirname = argv[0];
160 }
161 if (argc == 2)
162 system = argv[1];
163
164 openlog("savecore", LOG_ODELAY, LOG_AUTH);
165
166 read_kmem();
167 if (!dump_exists()) {
168/* (void)fprintf(stderr, "savecore: no core dump\n");*/
169 if (!force)
170 exit(0);
171 }
172 if (clear) {
173 clear_dump();
174 exit(0);
175 }
176 (void) time(&now);
177 check_kmem();
178 if (panicstr)
179 log(LOG_CRIT, "reboot after panic: %s\n", panic_mesg);
180 else
181 syslog(LOG_CRIT, "reboot\n");
182
183 if (access(dirname, W_OK) < 0) {
184 Perror(LOG_ERR, "%s: %m\n", dirname);
185 exit(1);
186 }
187 if ((!get_crashtime() || !check_space()) && !force)
188 exit(1);
189 save_core();
190 clear_dump();
191 exit(0);
192}
193
194dump_exists()
195{
196 int word;
197
198 Lseek(dumpfd, (off_t)(dumplo + ok(dump_nl[X_DUMPMAG].n_value)), L_SET);
199 Read(dumpfd, (char *)&word, sizeof (word));
200 if (verbose && word != dumpmag)
201 printf("magic number mismatch: %x != %x\n", word, dumpmag);
202 return (word == dumpmag);
203}
204
205clear_dump()
206{
207 int zero = 0;
208
209 Lseek(dumpfd, (off_t)(dumplo + ok(dump_nl[X_DUMPMAG].n_value)), L_SET);
210 Write(dumpfd, (char *)&zero, sizeof (zero));
211}
212
213char *
214find_dev(dev, type)
215 register dev_t dev;
216 register int type;
217{
218 register DIR *dfd = opendir(_PATH_DEV);
219 struct dirent *dir;
220 struct stat statb;
221 static char devname[MAXPATHLEN + 1];
222 char *dp;
223
224 strcpy(devname, _PATH_DEV);
225 while ((dir = readdir(dfd))) {
226 strcpy(devname + sizeof(_PATH_DEV) - 1, dir->d_name);
227 if (stat(devname, &statb)) {
228 perror(devname);
229 continue;
230 }
231 if ((statb.st_mode&S_IFMT) != type)
232 continue;
233 if (dev == statb.st_rdev) {
234 closedir(dfd);
235 dp = malloc(strlen(devname)+1);
236 strcpy(dp, devname);
237 return (dp);
238 }
239 }
240 closedir(dfd);
241 log(LOG_ERR, "Can't find device %d/%d\n", major(dev), minor(dev));
242 exit(1);
243 /*NOTREACHED*/
244}
245
246char *
247rawname(s)
248 char *s;
249{
250 static char name[MAXPATHLEN];
251 char *sl, *rindex();
252
253 if ((sl = rindex(s, '/')) == NULL || sl[1] == '0') {
254 log(LOG_ERR, "can't make raw dump device name from %s?\n", s);
255 return (s);
256 }
257 sprintf(name, "%.*s/r%s", sl - s, s, sl + 1);
258 return (name);
259}
260
261int cursyms[] =
262 { X_DUMPDEV, X_DUMPLO, X_VERSION, X_DUMPMAG, -1 };
263int dumpsyms[] =
264 { X_TIME, X_DUMPSIZE, X_VERSION, X_PANICSTR, X_DUMPMAG, -1 };
265read_kmem()
266{
267 register char *cp;
268 FILE *fp;
269 char *dump_sys;
270 int kmem, i;
271
272 dump_sys = system ? system : _PATH_UNIX;
273 nlist(_PATH_UNIX, current_nl);
274 nlist(dump_sys, dump_nl);
275 /*
276 * Some names we need for the currently running system,
277 * others for the system that was running when the dump was made.
278 * The values obtained from the current system are used
279 * to look for things in /dev/kmem that cannot be found
280 * in the dump_sys namelist, but are presumed to be the same
281 * (since the disk partitions are probably the same!)
282 */
283 for (i = 0; cursyms[i] != -1; i++)
284 if (current_nl[cursyms[i]].n_value == 0) {
285 log(LOG_ERR, "%s: %s not in namelist\n", _PATH_UNIX,
286 current_nl[cursyms[i]].n_name);
287 exit(1);
288 }
289 for (i = 0; dumpsyms[i] != -1; i++)
290 if (dump_nl[dumpsyms[i]].n_value == 0) {
291 log(LOG_ERR, "%s: %s not in namelist\n", dump_sys,
292 dump_nl[dumpsyms[i]].n_name);
293 exit(1);
294 }
295 kmem = Open(_PATH_KMEM, O_RDONLY);
296 Lseek(kmem, (long)current_nl[X_DUMPDEV].n_value, L_SET);
297 Read(kmem, (char *)&dumpdev, sizeof (dumpdev));
298 Lseek(kmem, (long)current_nl[X_DUMPLO].n_value, L_SET);
299 Read(kmem, (char *)&dumplo, sizeof (dumplo));
300 if (verbose)
301 printf("dumplo = %d (%d * %d)\n", dumplo, dumplo/DEV_BSIZE,
302 DEV_BSIZE);
303 Lseek(kmem, (long)current_nl[X_DUMPMAG].n_value, L_SET);
304 Read(kmem, (char *)&dumpmag, sizeof (dumpmag));
305 dumplo *= DEV_BSIZE;
306 ddname = find_dev(dumpdev, S_IFBLK);
307 dumpfd = Open(ddname, O_RDWR);
308 fp = fdopen(kmem, "r");
309 if (fp == NULL) {
310 log(LOG_ERR, "Couldn't fdopen kmem\n");
311 exit(1);
312 }
313 if (system)
314 return;
315 fseek(fp, (long)current_nl[X_VERSION].n_value, L_SET);
316 fgets(vers, sizeof (vers), fp);
317 fclose(fp);
318}
319
320check_kmem()
321{
322 FILE *fp;
323 register char *cp;
324
325 fp = fdopen(dumpfd, "r");
326 if (fp == NULL) {
327 log(LOG_ERR, "Can't fdopen dumpfd\n");
328 exit(1);
329 }
330
331 fseek(fp, (off_t)(dumplo+ok(dump_nl[X_VERSION].n_value)), L_SET);
332 fgets(core_vers, sizeof (core_vers), fp);
333 if (!eq(vers, core_vers) && system == 0) {
334 log(LOG_WARNING, "Warning: %s version mismatch:\n", _PATH_UNIX);
335 log(LOG_WARNING, "\t%s\n", vers);
336 log(LOG_WARNING, "and\t%s\n", core_vers);
337 }
338
339 fseek(fp, (off_t)(dumplo + ok(dump_nl[X_PANICSTR].n_value)), L_SET);
340 fread((char *)&panicstr, sizeof (panicstr), 1, fp);
341 if (panicstr) {
342 fseek(fp, dumplo + ok(panicstr), L_SET);
343 cp = panic_mesg;
344 do
345 *cp = getc(fp);
346 while (*cp++ && cp < &panic_mesg[sizeof(panic_mesg)]);
347 }
348 /* don't fclose(fp); we want the file descriptor */
349}
350
351get_crashtime()
352{
353 time_t clobber = (time_t)0;
354
355 Lseek(dumpfd, (off_t)(dumplo + ok(dump_nl[X_TIME].n_value)), L_SET);
356 Read(dumpfd, (char *)&dumptime, sizeof dumptime);
357 if (dumptime == 0) {
358 if (verbose)
359 printf("Dump time is zero.\n");
360 return (0);
361 }
362 printf("System went down at %s", ctime(&dumptime));
363 if (dumptime < now - LEEWAY || dumptime > now + LEEWAY) {
364 printf("dump time is unreasonable\n");
365 return (0);
366 }
367 return (1);
368}
369
370char *
371path(file)
372 char *file;
373{
374 register char *cp = malloc(strlen(file) + strlen(dirname) + 2);
375
376 (void) strcpy(cp, dirname);
377 (void) strcat(cp, "/");
378 (void) strcat(cp, file);
379 return (cp);
380}
381
382check_space()
383{
384 long minfree, spacefree;
385 struct statfs fsbuf;
386
387 if (statfs(dirname, &fsbuf) < 0) {
388 Perror(LOG_ERR, "%s: %m\n", dirname);
389 exit(1);
390 }
391 spacefree = fsbuf.f_bavail * fsbuf.f_fsize / 1024;
392 minfree = read_number("minfree");
393 if (minfree > 0 && spacefree - dumpsize < minfree) {
394 log(LOG_WARNING, "Dump omitted, not enough space on device\n");
395 return (0);
396 }
397 if (spacefree - dumpsize < minfree)
398 log(LOG_WARNING,
399 "Dump performed, but free space threshold crossed\n");
400 return (1);
401}
402
403read_number(fn)
404 char *fn;
405{
406 char lin[80];
407 register FILE *fp;
408
409 fp = fopen(path(fn), "r");
410 if (fp == NULL)
411 return (0);
412 if (fgets(lin, 80, fp) == NULL) {
413 fclose(fp);
414 return (0);
415 }
416 fclose(fp);
417 return (atoi(lin));
418}
419
420/*#define BUFSIZE (256*1024) /* 1/4 Mb */
421#define BUFSIZE (8*1024)
422
423save_core()
424{
425 register int n;
426 register char *cp;
427 register int ifd, ofd, bounds;
428 int ret;
429 char *bfile;
430 register FILE *fp;
431
432 cp = malloc(BUFSIZE);
433 if (cp == 0) {
434 log(LOG_ERR, "savecore: Can't allocate i/o buffer.\n");
435 return;
436 }
437 bounds = read_number("bounds");
438 ifd = Open(system ? system : _PATH_UNIX, O_RDONLY);
439 (void)sprintf(cp, "system.%d", bounds);
440 ofd = Create(path(cp), 0644);
441 while((n = Read(ifd, cp, BUFSIZE)) > 0)
442 Write(ofd, cp, n);
443 close(ifd);
444 close(ofd);
445 if ((ifd = open(rawname(ddname), O_RDONLY)) == -1) {
446 log(LOG_WARNING, "Can't open %s (%m); using block device",
447 rawname(ddname));
448 ifd = dumpfd;
449 }
450 Lseek(dumpfd, (off_t)(dumplo + ok(dump_nl[X_DUMPSIZE].n_value)), L_SET);
451 Read(dumpfd, (char *)&dumpsize, sizeof (dumpsize));
452 (void)sprintf(cp, "ram.%d", bounds);
453 ofd = Create(path(cp), 0644);
454 Lseek(ifd, (off_t)dumplo, L_SET);
455 dumpsize *= NBPG;
456 log(LOG_NOTICE, "Saving %d bytes of image in ram.%d\n",
457 dumpsize, bounds);
458 while (dumpsize > 0) {
459 n = read(ifd, cp,
460 dumpsize > BUFSIZE ? BUFSIZE : dumpsize);
461 if (n <= 0) {
462 if (n == 0)
463 log(LOG_WARNING,
464 "WARNING: EOF on dump device; %s\n",
465 "ram file may be incomplete");
466 else
467 Perror(LOG_ERR, "read from dumpdev: %m",
468 "read");
469 break;
470 }
471 if ((ret = write(ofd, cp, n)) < n) {
472 if (ret < 0)
473 Perror(LOG_ERR, "write: %m", "write");
474 else
475 log(LOG_ERR, "short write: wrote %d of %d\n",
476 ret, n);
477 log(LOG_WARNING, "WARNING: ram file may be incomplete\n");
478 break;
479 }
480 dumpsize -= n;
481 }
482 close(ifd);
483 close(ofd);
484 bfile = path("bounds");
485 fp = fopen(bfile, "w");
486 if (fp) {
487 fprintf(fp, "%d\n", bounds+1);
488 fclose(fp);
489 } else
490 Perror(LOG_ERR, "Can't create bounds file %s: %m", bfile);
491 free(cp);
492}
493
494/*
495 * Versions of std routines that exit on error.
496 */
497Open(name, rw)
498 char *name;
499 int rw;
500{
501 int fd;
502
503 fd = open(name, rw);
504 if (fd < 0) {
505 Perror(LOG_ERR, "%s: %m", name);
506 exit(1);
507 }
508 return (fd);
509}
510
511Read(fd, buff, size)
512 int fd, size;
513 char *buff;
514{
515 int ret;
516
517 ret = read(fd, buff, size);
518 if (ret < 0) {
519 Perror(LOG_ERR, "read: %m", "read");
520 exit(1);
521 }
522 return (ret);
523}
524
525off_t
526Lseek(fd, off, flag)
527 int fd, flag;
528 long off;
529{
530 long ret;
531
532 ret = lseek(fd, off, flag);
533 if (ret == -1) {
534 Perror(LOG_ERR, "lseek: %m", "lseek");
535 exit(1);
536 }
537 return (ret);
538}
539
540Create(file, mode)
541 char *file;
542 int mode;
543{
544 register int fd;
545
546 fd = creat(file, mode);
547 if (fd < 0) {
548 Perror(LOG_ERR, "%s: %m", file);
549 exit(1);
550 }
551 return (fd);
552}
553
554Write(fd, buf, size)
555 int fd, size;
556 char *buf;
557{
558 int n;
559
560 if ((n = write(fd, buf, size)) < size) {
561 if (n < 0)
562 Perror(LOG_ERR, "write: %m", "write");
563 else
564 log(LOG_ERR, "short write: wrote %d of %d\n", n, size);
565 exit(1);
566 }
567}
568
569/* VARARGS2 */
570log(level, msg, a1, a2)
571 int level;
572 char *msg;
573{
574
575 fprintf(stderr, msg, a1, a2);
576 syslog(level, msg, a1, a2);
577}
578
579Perror(level, msg, s)
580 int level;
581 char *msg, *s;
582{
583 int oerrno = errno;
584
585 perror(s);
586 errno = oerrno;
587 syslog(level, msg, s);
588}
589
590usage()
591{
592 (void)fprintf(stderr, "usage: savecore [-cfv] dirname [system]\n");
593 exit(1);
594}