xref: /freebsd/lib/libutil/kinfo_getvmobject.c (revision a2f733abcff64628b7771a47089628b7327a88bd)
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/types.h>
29 #include <sys/sysctl.h>
30 #include <sys/user.h>
31 #include <stdlib.h>
32 #include <string.h>
33 
34 #include "libutil.h"
35 
36 static struct kinfo_vmobject *
kinfo_getvmobject_impl(int * cntp,const char * vmobjsysctl)37 kinfo_getvmobject_impl(int *cntp, const char *vmobjsysctl)
38 {
39 	char *buf, *bp, *ep;
40 	struct kinfo_vmobject *kvo, *list, *kp;
41 	size_t len;
42 	int cnt, i;
43 
44 	buf = NULL;
45 	for (i = 0; i < 3; i++) {
46 		if (sysctlbyname(vmobjsysctl, NULL, &len, NULL, 0) < 0) {
47 			free(buf);
48 			return (NULL);
49 		}
50 		buf = reallocf(buf, len);
51 		if (buf == NULL)
52 			return (NULL);
53 		if (sysctlbyname(vmobjsysctl, buf, &len, NULL, 0) == 0)
54 			goto unpack;
55 		if (errno != ENOMEM) {
56 			free(buf);
57 			return (NULL);
58 		}
59 	}
60 	free(buf);
61 	return (NULL);
62 
63 unpack:
64 	/* Count items */
65 	cnt = 0;
66 	bp = buf;
67 	ep = buf + len;
68 	while (bp < ep) {
69 		kvo = (struct kinfo_vmobject *)(uintptr_t)bp;
70 		bp += kvo->kvo_structsize;
71 		cnt++;
72 	}
73 
74 	list = calloc(cnt, sizeof(*list));
75 	if (list == NULL) {
76 		free(buf);
77 		return (NULL);
78 	}
79 
80 	/* Unpack */
81 	bp = buf;
82 	kp = list;
83 	while (bp < ep) {
84 		kvo = (struct kinfo_vmobject *)(uintptr_t)bp;
85 		memcpy(kp, kvo, kvo->kvo_structsize);
86 		bp += kvo->kvo_structsize;
87 		kp->kvo_structsize = sizeof(*kp);
88 		kp++;
89 	}
90 	free(buf);
91 	*cntp = cnt;
92 	return (list);
93 }
94 
95 struct kinfo_vmobject *
kinfo_getvmobject(int * cntp)96 kinfo_getvmobject(int *cntp)
97 {
98 	return (kinfo_getvmobject_impl(cntp, "vm.objects"));
99 }
100 
101 struct kinfo_vmobject *
kinfo_getswapvmobject(int * cntp)102 kinfo_getswapvmobject(int *cntp)
103 {
104 	return (kinfo_getvmobject_impl(cntp, "vm.swap_objects"));
105 }
106