xref: /freebsd/lib/libutil/kinfo_getvmobject.c (revision dd41de95a84d979615a2ef11df6850622bf6184e)
1 /*
2  * Copyright (c) 2013 Hudson River Trading LLC
3  * Written by: John H. Baldwin <jhb@FreeBSD.org>
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include <sys/types.h>
32 #include <sys/sysctl.h>
33 #include <sys/user.h>
34 #include <stdlib.h>
35 #include <string.h>
36 
37 #include "libutil.h"
38 
39 struct kinfo_vmobject *
40 kinfo_getvmobject(int *cntp)
41 {
42 	char *buf, *bp, *ep;
43 	struct kinfo_vmobject *kvo, *list, *kp;
44 	size_t len;
45 	int cnt, i;
46 
47 	buf = NULL;
48 	for (i = 0; i < 3; i++) {
49 		if (sysctlbyname("vm.objects", NULL, &len, NULL, 0) < 0) {
50 			free(buf);
51 			return (NULL);
52 		}
53 		buf = reallocf(buf, len);
54 		if (buf == NULL)
55 			return (NULL);
56 		if (sysctlbyname("vm.objects", buf, &len, NULL, 0) == 0)
57 			goto unpack;
58 		if (errno != ENOMEM) {
59 			free(buf);
60 			return (NULL);
61 		}
62 	}
63 	free(buf);
64 	return (NULL);
65 
66 unpack:
67 	/* Count items */
68 	cnt = 0;
69 	bp = buf;
70 	ep = buf + len;
71 	while (bp < ep) {
72 		kvo = (struct kinfo_vmobject *)(uintptr_t)bp;
73 		bp += kvo->kvo_structsize;
74 		cnt++;
75 	}
76 
77 	list = calloc(cnt, sizeof(*list));
78 	if (list == NULL) {
79 		free(buf);
80 		return (NULL);
81 	}
82 
83 	/* Unpack */
84 	bp = buf;
85 	kp = list;
86 	while (bp < ep) {
87 		kvo = (struct kinfo_vmobject *)(uintptr_t)bp;
88 		memcpy(kp, kvo, kvo->kvo_structsize);
89 		bp += kvo->kvo_structsize;
90 		kp->kvo_structsize = sizeof(*kp);
91 		kp++;
92 	}
93 	free(buf);
94 	*cntp = cnt;
95 	return (list);
96 }
97