xref: /freebsd/lib/libutil/kinfo_getvmobject.c (revision 734e82fe33aa764367791a7d603b383996c6b40b)
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 #include <sys/types.h>
30 #include <sys/sysctl.h>
31 #include <sys/user.h>
32 #include <stdlib.h>
33 #include <string.h>
34 
35 #include "libutil.h"
36 
37 static struct kinfo_vmobject *
38 kinfo_getvmobject_impl(int *cntp, const char *vmobjsysctl)
39 {
40 	char *buf, *bp, *ep;
41 	struct kinfo_vmobject *kvo, *list, *kp;
42 	size_t len;
43 	int cnt, i;
44 
45 	buf = NULL;
46 	for (i = 0; i < 3; i++) {
47 		if (sysctlbyname(vmobjsysctl, NULL, &len, NULL, 0) < 0) {
48 			free(buf);
49 			return (NULL);
50 		}
51 		buf = reallocf(buf, len);
52 		if (buf == NULL)
53 			return (NULL);
54 		if (sysctlbyname(vmobjsysctl, buf, &len, NULL, 0) == 0)
55 			goto unpack;
56 		if (errno != ENOMEM) {
57 			free(buf);
58 			return (NULL);
59 		}
60 	}
61 	free(buf);
62 	return (NULL);
63 
64 unpack:
65 	/* Count items */
66 	cnt = 0;
67 	bp = buf;
68 	ep = buf + len;
69 	while (bp < ep) {
70 		kvo = (struct kinfo_vmobject *)(uintptr_t)bp;
71 		bp += kvo->kvo_structsize;
72 		cnt++;
73 	}
74 
75 	list = calloc(cnt, sizeof(*list));
76 	if (list == NULL) {
77 		free(buf);
78 		return (NULL);
79 	}
80 
81 	/* Unpack */
82 	bp = buf;
83 	kp = list;
84 	while (bp < ep) {
85 		kvo = (struct kinfo_vmobject *)(uintptr_t)bp;
86 		memcpy(kp, kvo, kvo->kvo_structsize);
87 		bp += kvo->kvo_structsize;
88 		kp->kvo_structsize = sizeof(*kp);
89 		kp++;
90 	}
91 	free(buf);
92 	*cntp = cnt;
93 	return (list);
94 }
95 
96 struct kinfo_vmobject *
97 kinfo_getvmobject(int *cntp)
98 {
99 	return (kinfo_getvmobject_impl(cntp, "vm.objects"));
100 }
101 
102 struct kinfo_vmobject *
103 kinfo_getswapvmobject(int *cntp)
104 {
105 	return (kinfo_getvmobject_impl(cntp, "vm.swap_objects"));
106 }
107