GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: usr.bin/vmstat/dkstats.c Lines: 0 321 0.0 %
Date: 2017-11-07 Branches: 0 110 0.0 %

Line Branch Exec Source
1
/*	$OpenBSD: dkstats.c,v 1.40 2017/05/30 05:57:46 tedu Exp $	*/
2
/*	$NetBSD: dkstats.c,v 1.1 1996/05/10 23:19:27 thorpej Exp $	*/
3
4
/*
5
 * Copyright (c) 1996 John M. Vinopal
6
 * All rights reserved.
7
 *
8
 * Redistribution and use in source and binary forms, with or without
9
 * modification, are permitted provided that the following conditions
10
 * are met:
11
 * 1. Redistributions of source code must retain the above copyright
12
 *    notice, this list of conditions and the following disclaimer.
13
 * 2. Redistributions in binary form must reproduce the above copyright
14
 *    notice, this list of conditions and the following disclaimer in the
15
 *    documentation and/or other materials provided with the distribution.
16
 * 3. All advertising materials mentioning features or use of this software
17
 *    must display the following acknowledgement:
18
 *      This product includes software developed for the NetBSD Project
19
 *      by John M. Vinopal.
20
 * 4. The name of the author may not be used to endorse or promote products
21
 *    derived from this software without specific prior written permission.
22
 *
23
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
24
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
25
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
26
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
27
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
28
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
29
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
30
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
31
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33
 * SUCH DAMAGE.
34
 */
35
36
#include <sys/time.h>
37
#include <sys/disk.h>
38
#include <sys/sched.h>
39
#include <sys/sysctl.h>
40
#include <sys/tty.h>
41
42
#include <err.h>
43
#include <fcntl.h>
44
#include <kvm.h>
45
#include <limits.h>
46
#include <nlist.h>
47
#include <stdio.h>
48
#include <stdlib.h>
49
#include <string.h>
50
#include <unistd.h>
51
#include "dkstats.h"
52
53
#if !defined(NOKVM)
54
static struct nlist namelist[] = {
55
#define	X_TK_NIN	0		/* sysctl */
56
	{ "_tk_nin" },
57
#define	X_TK_NOUT	1		/* sysctl */
58
	{ "_tk_nout" },
59
#define	X_CP_TIME	2		/* sysctl */
60
	{ "_cp_time" },
61
#define	X_HZ		3		/* sysctl */
62
	{ "_hz" },
63
#define	X_STATHZ	4		/* sysctl */
64
	{ "_stathz" },
65
#define X_DISK_COUNT	5		/* sysctl */
66
	{ "_disk_count" },
67
#define X_DISKLIST	6		/* sysctl */
68
	{ "_disklist" },
69
	{ NULL },
70
};
71
#define	KVM_ERROR(_string) {						\
72
	warnx("%s", (_string));						\
73
	errx(1, "%s", kvm_geterr(kd));					\
74
}
75
76
/*
77
 * Dereference the namelist pointer `v' and fill in the local copy
78
 * 'p' which is of size 's'.
79
 */
80
#define deref_nl(v, p, s) deref_kptr((void *)namelist[(v)].n_value, (p), (s));
81
static void deref_kptr(void *, void *, size_t);
82
#endif /* !defined(NOKVM) */
83
84
/* Structures to hold the statistics. */
85
struct _disk	cur, last;
86
87
/* Kernel pointers: nlistf and memf defined in calling program. */
88
#if !defined(NOKVM)
89
extern kvm_t	*kd;
90
#endif
91
extern char	*nlistf;
92
extern char	*memf;
93
94
#if !defined(NOKVM)
95
/* Pointer to list of disks. */
96
static struct disk	*dk_drivehead = NULL;
97
#endif
98
99
/* Backward compatibility references. */
100
int		dk_ndrive = 0;
101
int		*dk_select;
102
char		**dr_name;
103
104
/* Missing from <sys/time.h> */
105
#define timerset(tvp, uvp) \
106
	((uvp)->tv_sec = (tvp)->tv_sec);		\
107
	((uvp)->tv_usec = (tvp)->tv_usec)
108
109
#define SWAP(fld)	tmp = cur.fld;				\
110
			cur.fld -= last.fld;			\
111
			last.fld = tmp
112
113
/*
114
 * Take the delta between the present values and the last recorded
115
 * values, storing the present values in the 'last' structure, and
116
 * the delta values in the 'cur' structure.
117
 */
118
void
119
dkswap(void)
120
{
121
	u_int64_t tmp;
122
	int	i;
123
124
	for (i = 0; i < cur.dk_ndrive; i++) {
125
		struct timeval	tmp_timer;
126
127
		if (!cur.dk_select[i])
128
			continue;
129
130
		/* Delta Values. */
131
		SWAP(dk_rxfer[i]);
132
		SWAP(dk_wxfer[i]);
133
		SWAP(dk_seek[i]);
134
		SWAP(dk_rbytes[i]);
135
		SWAP(dk_wbytes[i]);
136
137
		/* Delta Time. */
138
		timerclear(&tmp_timer);
139
		timerset(&(cur.dk_time[i]), &tmp_timer);
140
		timersub(&tmp_timer, &(last.dk_time[i]), &(cur.dk_time[i]));
141
		timerclear(&(last.dk_time[i]));
142
		timerset(&tmp_timer, &(last.dk_time[i]));
143
	}
144
	for (i = 0; i < CPUSTATES; i++) {
145
		long ltmp;
146
147
		ltmp = cur.cp_time[i];
148
		cur.cp_time[i] -= last.cp_time[i];
149
		last.cp_time[i] = ltmp;
150
	}
151
	SWAP(tk_nin);
152
	SWAP(tk_nout);
153
154
#undef SWAP
155
}
156
157
/*
158
 * Read the disk statistics for each disk in the disk list.
159
 * Also collect statistics for tty i/o and cpu ticks.
160
 */
161
void
162
dkreadstats(void)
163
{
164
#if !defined(NOKVM)
165
	struct disk	cur_disk, *p;
166
#endif
167
	int		i, j, mib[3];
168
	size_t		size;
169
	char		*disknames, *name, *bufpp, **dk_name;
170
	struct diskstats *q;
171
172
	last.dk_ndrive = cur.dk_ndrive;
173
174
	if (nlistf == NULL && memf == NULL) {
175
		/* Get the number of attached drives. */
176
		mib[0] = CTL_HW;
177
		mib[1] = HW_DISKCOUNT;
178
		size = sizeof(dk_ndrive);
179
		if (sysctl(mib, 2, &dk_ndrive, &size, NULL, 0) < 0 ) {
180
			warn("could not read hw.diskcount");
181
			dk_ndrive = 0;
182
		}
183
184
		if (cur.dk_ndrive != dk_ndrive) {
185
			/* Re-read the disk names. */
186
			dk_name = calloc((size_t)dk_ndrive, sizeof(char *));
187
			if (dk_name == NULL)
188
				err(1, NULL);
189
			mib[0] = CTL_HW;
190
			mib[1] = HW_DISKNAMES;
191
			size = 0;
192
			if (sysctl(mib, 2, NULL, &size, NULL, 0) < 0)
193
				err(1, "can't get hw.disknames");
194
			disknames = malloc(size);
195
			if (disknames == NULL)
196
				err(1, NULL);
197
			if (sysctl(mib, 2, disknames, &size, NULL, 0) < 0)
198
				err(1, "can't get hw.disknames");
199
			bufpp = disknames;
200
			for (i = 0; i < dk_ndrive &&
201
			    (name = strsep(&bufpp, ",")) != NULL; i++)
202
				dk_name[i] = name;
203
			for (i = 0; i < dk_ndrive; i++) {
204
				char *ep = strchr(dk_name[i], ':');
205
				if (ep)
206
					*ep = '\0';
207
			}
208
			disknames = cur.dk_name[0];	/* To free old names. */
209
210
			if (dk_ndrive < cur.dk_ndrive) {
211
				for (i = 0, j = 0; i < dk_ndrive; i++, j++) {
212
					while (j < cur.dk_ndrive &&
213
					    strcmp(cur.dk_name[j], dk_name[i]))
214
						j++;
215
					if (i == j) continue;
216
217
					if (j >= cur.dk_ndrive) {
218
						cur.dk_select[i] = 1;
219
						last.dk_rxfer[i] = 0;
220
						last.dk_wxfer[i] = 0;
221
						last.dk_seek[i] = 0;
222
						last.dk_rbytes[i] = 0;
223
						last.dk_wbytes[i] = 0;
224
						memset(&last.dk_time[i], 0,
225
						    sizeof(struct timeval));
226
						continue;
227
					}
228
229
					cur.dk_select[i] = cur.dk_select[j];
230
					last.dk_rxfer[i] = last.dk_rxfer[j];
231
					last.dk_wxfer[i] = last.dk_wxfer[j];
232
					last.dk_seek[i] = last.dk_seek[j];
233
					last.dk_rbytes[i] = last.dk_rbytes[j];
234
					last.dk_wbytes[i] = last.dk_wbytes[j];
235
					last.dk_time[i] = last.dk_time[j];
236
				}
237
238
				cur.dk_select = reallocarray(cur.dk_select,
239
				    dk_ndrive, sizeof(*cur.dk_select));
240
				cur.dk_rxfer = reallocarray(cur.dk_rxfer,
241
				    dk_ndrive, sizeof(*cur.dk_rxfer));
242
				cur.dk_wxfer = reallocarray(cur.dk_wxfer,
243
				    dk_ndrive, sizeof(*cur.dk_wxfer));
244
				cur.dk_seek = reallocarray(cur.dk_seek,
245
				    dk_ndrive, sizeof(*cur.dk_seek));
246
				cur.dk_rbytes = reallocarray(cur.dk_rbytes,
247
				    dk_ndrive, sizeof(*cur.dk_rbytes));
248
				cur.dk_wbytes = reallocarray(cur.dk_wbytes,
249
				    dk_ndrive, sizeof(*cur.dk_wbytes));
250
				cur.dk_time = reallocarray(cur.dk_time,
251
				    dk_ndrive, sizeof(*cur.dk_time));
252
				last.dk_rxfer = reallocarray(last.dk_rxfer,
253
				    dk_ndrive, sizeof(*last.dk_rxfer));
254
				last.dk_wxfer = reallocarray(last.dk_wxfer,
255
				    dk_ndrive, sizeof(*last.dk_wxfer));
256
				last.dk_seek = reallocarray(last.dk_seek,
257
				    dk_ndrive, sizeof(*last.dk_seek));
258
				last.dk_rbytes = reallocarray(last.dk_rbytes,
259
				    dk_ndrive, sizeof(*last.dk_rbytes));
260
				last.dk_wbytes = reallocarray(last.dk_wbytes,
261
				    dk_ndrive, sizeof(*last.dk_wbytes));
262
				last.dk_time = reallocarray(last.dk_time,
263
				    dk_ndrive, sizeof(*last.dk_time));
264
265
				if (!cur.dk_select || !cur.dk_rxfer ||
266
				    !cur.dk_wxfer || !cur.dk_seek ||
267
				    !cur.dk_rbytes || !cur.dk_wbytes ||
268
				    !cur.dk_time || !last.dk_rxfer ||
269
				    !last.dk_wxfer || !last.dk_seek ||
270
				    !last.dk_rbytes || !last.dk_wbytes ||
271
				    !last.dk_time)
272
					errx(1, "Memory allocation failure.");
273
			} else {
274
				cur.dk_select = reallocarray(cur.dk_select,
275
				    dk_ndrive, sizeof(*cur.dk_select));
276
				cur.dk_rxfer = reallocarray(cur.dk_rxfer,
277
				    dk_ndrive, sizeof(*cur.dk_rxfer));
278
				cur.dk_wxfer = reallocarray(cur.dk_wxfer,
279
				    dk_ndrive, sizeof(*cur.dk_wxfer));
280
				cur.dk_seek = reallocarray(cur.dk_seek,
281
				    dk_ndrive, sizeof(*cur.dk_seek));
282
				cur.dk_rbytes = reallocarray(cur.dk_rbytes,
283
				    dk_ndrive, sizeof(*cur.dk_rbytes));
284
				cur.dk_wbytes = reallocarray(cur.dk_wbytes,
285
				    dk_ndrive, sizeof(*cur.dk_wbytes));
286
				cur.dk_time = reallocarray(cur.dk_time,
287
				    dk_ndrive, sizeof(*cur.dk_time));
288
				last.dk_rxfer = reallocarray(last.dk_rxfer,
289
				    dk_ndrive, sizeof(*last.dk_rxfer));
290
				last.dk_wxfer = reallocarray(last.dk_wxfer,
291
				    dk_ndrive, sizeof(*last.dk_wxfer));
292
				last.dk_seek = reallocarray(last.dk_seek,
293
				    dk_ndrive, sizeof(*last.dk_seek));
294
				last.dk_rbytes = reallocarray(last.dk_rbytes,
295
				    dk_ndrive, sizeof(*last.dk_rbytes));
296
				last.dk_wbytes = reallocarray(last.dk_wbytes,
297
				    dk_ndrive, sizeof(*last.dk_wbytes));
298
				last.dk_time = reallocarray(last.dk_time,
299
				    dk_ndrive, sizeof(*last.dk_time));
300
301
				if (!cur.dk_select || !cur.dk_rxfer ||
302
				    !cur.dk_wxfer || !cur.dk_seek ||
303
				    !cur.dk_rbytes || !cur.dk_wbytes ||
304
				    !cur.dk_time || !last.dk_rxfer ||
305
				    !last.dk_wxfer || !last.dk_seek ||
306
				    !last.dk_rbytes || !last.dk_wbytes ||
307
				    !last.dk_time)
308
					errx(1, "Memory allocation failure.");
309
310
				for (i = dk_ndrive - 1, j = cur.dk_ndrive - 1;
311
				     i >= 0; i--) {
312
313
					if (j < 0 ||
314
					    strcmp(cur.dk_name[j], dk_name[i]))
315
					{
316
						cur.dk_select[i] = 1;
317
						last.dk_rxfer[i] = 0;
318
						last.dk_wxfer[i] = 0;
319
						last.dk_seek[i] = 0;
320
						last.dk_rbytes[i] = 0;
321
						last.dk_wbytes[i] = 0;
322
						memset(&last.dk_time[i], 0,
323
						    sizeof(struct timeval));
324
						continue;
325
					}
326
327
					if (i > j) {
328
						cur.dk_select[i] =
329
						    cur.dk_select[j];
330
						last.dk_rxfer[i] =
331
						    last.dk_rxfer[j];
332
						last.dk_wxfer[i] =
333
						    last.dk_wxfer[j];
334
						last.dk_seek[i] =
335
						    last.dk_seek[j];
336
						last.dk_rbytes[i] =
337
						    last.dk_rbytes[j];
338
						last.dk_wbytes[i] =
339
						    last.dk_wbytes[j];
340
						last.dk_time[i] =
341
						    last.dk_time[j];
342
					}
343
					j--;
344
				}
345
			}
346
347
			cur.dk_ndrive = dk_ndrive;
348
			free(disknames);
349
			cur.dk_name = dk_name;
350
			dr_name = cur.dk_name;
351
			dk_select = cur.dk_select;
352
		}
353
354
		size = cur.dk_ndrive * sizeof(struct diskstats);
355
		mib[0] = CTL_HW;
356
		mib[1] = HW_DISKSTATS;
357
		q = malloc(size);
358
		if (q == NULL)
359
			err(1, NULL);
360
		if (sysctl(mib, 2, q, &size, NULL, 0) < 0) {
361
#ifdef	DEBUG
362
			warn("could not read hw.diskstats");
363
#endif	/* DEBUG */
364
			memset(q, 0, cur.dk_ndrive * sizeof(struct diskstats));
365
		}
366
367
		for (i = 0; i < cur.dk_ndrive; i++)	{
368
			cur.dk_rxfer[i] = q[i].ds_rxfer;
369
			cur.dk_wxfer[i] = q[i].ds_wxfer;
370
			cur.dk_seek[i] = q[i].ds_seek;
371
			cur.dk_rbytes[i] = q[i].ds_rbytes;
372
			cur.dk_wbytes[i] = q[i].ds_wbytes;
373
			timerset(&(q[i].ds_time), &(cur.dk_time[i]));
374
		}
375
		free(q);
376
377
		size = sizeof(cur.cp_time);
378
		mib[0] = CTL_KERN;
379
		mib[1] = KERN_CPTIME;
380
		if (sysctl(mib, 2, cur.cp_time, &size, NULL, 0) < 0) {
381
			warn("could not read kern.cp_time");
382
			memset(cur.cp_time, 0, sizeof(cur.cp_time));
383
		}
384
		size = sizeof(cur.tk_nin);
385
		mib[0] = CTL_KERN;
386
		mib[1] = KERN_TTY;
387
		mib[2] = KERN_TTY_TKNIN;
388
		if (sysctl(mib, 3, &cur.tk_nin, &size, NULL, 0) < 0) {
389
			warn("could not read kern.tty.tk_nin");
390
			cur.tk_nin = 0;
391
		}
392
		size = sizeof(cur.tk_nin);
393
		mib[0] = CTL_KERN;
394
		mib[1] = KERN_TTY;
395
		mib[2] = KERN_TTY_TKNOUT;
396
		if (sysctl(mib, 3, &cur.tk_nout, &size, NULL, 0) < 0) {
397
			warn("could not read kern.tty.tk_nout");
398
			cur.tk_nout = 0;
399
		}
400
	} else {
401
#if !defined(NOKVM)
402
		p = dk_drivehead;
403
404
		for (i = 0; i < cur.dk_ndrive; i++) {
405
			deref_kptr(p, &cur_disk, sizeof(cur_disk));
406
			cur.dk_rxfer[i] = cur_disk.dk_rxfer;
407
			cur.dk_wxfer[i] = cur_disk.dk_wxfer;
408
			cur.dk_seek[i] = cur_disk.dk_seek;
409
			cur.dk_rbytes[i] = cur_disk.dk_rbytes;
410
			cur.dk_wbytes[i] = cur_disk.dk_wbytes;
411
			timerset(&(cur_disk.dk_time), &(cur.dk_time[i]));
412
			p = TAILQ_NEXT(&cur_disk, dk_link);
413
		}
414
		deref_nl(X_CP_TIME, cur.cp_time, sizeof(cur.cp_time));
415
		deref_nl(X_TK_NIN, &cur.tk_nin, sizeof(cur.tk_nin));
416
		deref_nl(X_TK_NOUT, &cur.tk_nout, sizeof(cur.tk_nout));
417
#endif /* !defined(NOKVM) */
418
	}
419
}
420
421
/*
422
 * Perform all of the initialization and memory allocation needed to
423
 * track disk statistics.
424
 */
425
int
426
dkinit(int sel)
427
{
428
#if !defined(NOKVM)
429
	struct disklist_head disk_head;
430
	struct disk	cur_disk, *p;
431
        char		errbuf[_POSIX2_LINE_MAX];
432
#endif
433
	static int	once = 0;
434
	extern int	hz;
435
	int		i, mib[2];
436
	size_t		size;
437
	struct clockinfo clkinfo;
438
	char		*disknames, *name, *bufpp;
439
440
	if (once)
441
		return(1);
442
443
	if (nlistf != NULL || memf != NULL) {
444
#if !defined(NOKVM)
445
		/* Open the kernel. */
446
		if (kd == NULL &&
447
		    (kd = kvm_openfiles(nlistf, memf, NULL, O_RDONLY,
448
		    errbuf)) == NULL)
449
			errx(1, "kvm_openfiles: %s", errbuf);
450
451
		/* Obtain the namelist symbols from the kernel. */
452
		if (kvm_nlist(kd, namelist))
453
			KVM_ERROR("kvm_nlist failed to read symbols.");
454
455
		/* Get the number of attached drives. */
456
		deref_nl(X_DISK_COUNT, &cur.dk_ndrive, sizeof(cur.dk_ndrive));
457
458
		if (cur.dk_ndrive < 0)
459
			errx(1, "invalid _disk_count %d.", cur.dk_ndrive);
460
461
		/* Get a pointer to the first disk. */
462
		deref_nl(X_DISKLIST, &disk_head, sizeof(disk_head));
463
		dk_drivehead = TAILQ_FIRST(&disk_head);
464
465
		/* Get ticks per second. */
466
		deref_nl(X_STATHZ, &hz, sizeof(hz));
467
		if (!hz)
468
		  deref_nl(X_HZ, &hz, sizeof(hz));
469
#endif /* !defined(NOKVM) */
470
	} else {
471
		/* Get the number of attached drives. */
472
		mib[0] = CTL_HW;
473
		mib[1] = HW_DISKCOUNT;
474
		size = sizeof(cur.dk_ndrive);
475
		if (sysctl(mib, 2, &cur.dk_ndrive, &size, NULL, 0) < 0 ) {
476
			warn("could not read hw.diskcount");
477
			cur.dk_ndrive = 0;
478
		}
479
480
		/* Get ticks per second. */
481
		mib[0] = CTL_KERN;
482
		mib[1] = KERN_CLOCKRATE;
483
		size = sizeof(clkinfo);
484
		if (sysctl(mib, 2, &clkinfo, &size, NULL, 0) < 0) {
485
			warn("could not read kern.clockrate");
486
			hz = 0;
487
		} else
488
			hz = clkinfo.stathz;
489
	}
490
491
	/* allocate space for the statistics */
492
	cur.dk_time = calloc((size_t)cur.dk_ndrive, sizeof(struct timeval));
493
	cur.dk_rxfer = calloc((size_t)cur.dk_ndrive, sizeof(u_int64_t));
494
	cur.dk_wxfer = calloc((size_t)cur.dk_ndrive, sizeof(u_int64_t));
495
	cur.dk_seek = calloc((size_t)cur.dk_ndrive, sizeof(u_int64_t));
496
	cur.dk_rbytes = calloc((size_t)cur.dk_ndrive, sizeof(u_int64_t));
497
	cur.dk_wbytes = calloc((size_t)cur.dk_ndrive, sizeof(u_int64_t));
498
	cur.dk_select = calloc((size_t)cur.dk_ndrive, sizeof(int));
499
	cur.dk_name = calloc((size_t)cur.dk_ndrive, sizeof(char *));
500
	last.dk_time = calloc((size_t)cur.dk_ndrive, sizeof(struct timeval));
501
	last.dk_rxfer = calloc((size_t)cur.dk_ndrive, sizeof(u_int64_t));
502
	last.dk_wxfer = calloc((size_t)cur.dk_ndrive, sizeof(u_int64_t));
503
	last.dk_seek = calloc((size_t)cur.dk_ndrive, sizeof(u_int64_t));
504
	last.dk_rbytes = calloc((size_t)cur.dk_ndrive, sizeof(u_int64_t));
505
	last.dk_wbytes = calloc((size_t)cur.dk_ndrive, sizeof(u_int64_t));
506
507
	if (!cur.dk_time || !cur.dk_rxfer || !cur.dk_wxfer || !cur.dk_seek ||
508
	    !cur.dk_rbytes || !cur.dk_wbytes || !cur.dk_select ||
509
	    !cur.dk_name || !last.dk_time || !last.dk_rxfer ||
510
	    !last.dk_wxfer || !last.dk_seek || !last.dk_rbytes ||
511
	    !last.dk_wbytes)
512
		errx(1, "Memory allocation failure.");
513
514
	/* Set up the compatibility interfaces. */
515
	dk_ndrive = cur.dk_ndrive;
516
	dk_select = cur.dk_select;
517
	dr_name = cur.dk_name;
518
519
	/* Read the disk names and set initial selection. */
520
	if (nlistf == NULL && memf == NULL) {
521
		mib[0] = CTL_HW;
522
		mib[1] = HW_DISKNAMES;
523
		size = 0;
524
		if (sysctl(mib, 2, NULL, &size, NULL, 0) < 0)
525
			err(1, "can't get hw.disknames");
526
		disknames = malloc(size);
527
		if (disknames == NULL)
528
			err(1, NULL);
529
		if (sysctl(mib, 2, disknames, &size, NULL, 0) < 0)
530
			err(1, "can't get hw.disknames");
531
		bufpp = disknames;
532
		for (i = 0; i < dk_ndrive && (name = strsep(&bufpp, ",")) != NULL; i++) {
533
			cur.dk_name[i] = name;
534
			cur.dk_select[i] = sel;
535
		}
536
		for (i = 0; i < dk_ndrive; i++) {
537
			char *ep = strchr(cur.dk_name[i], ':');
538
			if (ep)
539
				*ep = '\0';
540
		}
541
	} else {
542
#if !defined(NOKVM)
543
		p = dk_drivehead;
544
		for (i = 0; i < cur.dk_ndrive; i++) {
545
			char	buf[10];
546
547
			deref_kptr(p, &cur_disk, sizeof(cur_disk));
548
			deref_kptr(cur_disk.dk_name, buf, sizeof(buf));
549
			cur.dk_name[i] = strdup(buf);
550
			if (!cur.dk_name[i])
551
				errx(1, "Memory allocation failure.");
552
			cur.dk_select[i] = sel;
553
554
			p = TAILQ_NEXT(&cur_disk, dk_link);
555
		}
556
#endif /* !defined(NOKVM) */
557
	}
558
559
	/* Never do this initialization again. */
560
	once = 1;
561
	return(1);
562
}
563
564
#if !defined(NOKVM)
565
/*
566
 * Dereference the kernel pointer `kptr' and fill in the local copy
567
 * pointed to by `ptr'.  The storage space must be pre-allocated,
568
 * and the size of the copy passed in `len'.
569
 */
570
static void
571
deref_kptr(void *kptr, void *ptr, size_t len)
572
{
573
	char buf[128];
574
575
	if (kvm_read(kd, (u_long)kptr, ptr, len) != len) {
576
		memset(buf, 0, sizeof(buf));
577
		snprintf(buf, (sizeof(buf) - 1),
578
		     "can't dereference kptr 0x%lx", (u_long)kptr);
579
		KVM_ERROR(buf);
580
	}
581
}
582
#endif /* !defined(NOKVM) */