xref: /minix3/lib/libc/gen/asysctl.c (revision 0a6a1f1d05b60e214de2f05a7310ddd1f0e590e7)
1*0a6a1f1dSLionel Sambuc /*	$NetBSD: asysctl.c,v 1.1 2014/06/13 15:45:05 joerg Exp $ */
2*0a6a1f1dSLionel Sambuc 
3*0a6a1f1dSLionel Sambuc /*-
4*0a6a1f1dSLionel Sambuc  * Copyright (c) 2014 The NetBSD Foundation, Inc.
5*0a6a1f1dSLionel Sambuc  *	All rights reserved.
6*0a6a1f1dSLionel Sambuc  *
7*0a6a1f1dSLionel Sambuc  * This code is derived from software contributed to The NetBSD Foundation
8*0a6a1f1dSLionel Sambuc  * by Joerg Sonnenberger.
9*0a6a1f1dSLionel Sambuc  *
10*0a6a1f1dSLionel Sambuc  * Redistribution and use in source and binary forms, with or without
11*0a6a1f1dSLionel Sambuc  * modification, are permitted provided that the following conditions
12*0a6a1f1dSLionel Sambuc  * are met:
13*0a6a1f1dSLionel Sambuc  * 1. Redistributions of source code must retain the above copyright
14*0a6a1f1dSLionel Sambuc  *    notice, this list of conditions and the following disclaimer.
15*0a6a1f1dSLionel Sambuc  * 2. Redistributions in binary form must reproduce the above copyright
16*0a6a1f1dSLionel Sambuc  *    notice, this list of conditions and the following disclaimer in the
17*0a6a1f1dSLionel Sambuc  *    documentation and/or other materials provided with the distribution.
18*0a6a1f1dSLionel Sambuc  *
19*0a6a1f1dSLionel Sambuc  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20*0a6a1f1dSLionel Sambuc  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21*0a6a1f1dSLionel Sambuc  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22*0a6a1f1dSLionel Sambuc  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23*0a6a1f1dSLionel Sambuc  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24*0a6a1f1dSLionel Sambuc  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25*0a6a1f1dSLionel Sambuc  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26*0a6a1f1dSLionel Sambuc  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27*0a6a1f1dSLionel Sambuc  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28*0a6a1f1dSLionel Sambuc  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29*0a6a1f1dSLionel Sambuc  * POSSIBILITY OF SUCH DAMAGE.
30*0a6a1f1dSLionel Sambuc  */
31*0a6a1f1dSLionel Sambuc 
32*0a6a1f1dSLionel Sambuc #include <sys/cdefs.h>
33*0a6a1f1dSLionel Sambuc __RCSID("$NetBSD: asysctl.c,v 1.1 2014/06/13 15:45:05 joerg Exp $");
34*0a6a1f1dSLionel Sambuc 
35*0a6a1f1dSLionel Sambuc #include "namespace.h"
36*0a6a1f1dSLionel Sambuc #include <sys/sysctl.h>
37*0a6a1f1dSLionel Sambuc #include <errno.h>
38*0a6a1f1dSLionel Sambuc #include <limits.h>
39*0a6a1f1dSLionel Sambuc #include <stdlib.h>
40*0a6a1f1dSLionel Sambuc 
__weak_alias(asysctl,_asysctl)41*0a6a1f1dSLionel Sambuc __weak_alias(asysctl,_asysctl)
42*0a6a1f1dSLionel Sambuc __weak_alias(asysctlbyname,_asysctlbyname)
43*0a6a1f1dSLionel Sambuc 
44*0a6a1f1dSLionel Sambuc void *
45*0a6a1f1dSLionel Sambuc asysctl(const int *oids, size_t oidlen, size_t *len)
46*0a6a1f1dSLionel Sambuc {
47*0a6a1f1dSLionel Sambuc 	void *data;
48*0a6a1f1dSLionel Sambuc 
49*0a6a1f1dSLionel Sambuc 	*len = 0;
50*0a6a1f1dSLionel Sambuc 	data = NULL;
51*0a6a1f1dSLionel Sambuc 
52*0a6a1f1dSLionel Sambuc 	for (;;) {
53*0a6a1f1dSLionel Sambuc 		if (sysctl(oids, oidlen, data, len, NULL, 0) == 0) {
54*0a6a1f1dSLionel Sambuc 			if (*len == 0) {
55*0a6a1f1dSLionel Sambuc 				free(data);
56*0a6a1f1dSLionel Sambuc 				return NULL;
57*0a6a1f1dSLionel Sambuc 			}
58*0a6a1f1dSLionel Sambuc 			if (data != NULL)
59*0a6a1f1dSLionel Sambuc 				return data;
60*0a6a1f1dSLionel Sambuc 			errno = ENOMEM;
61*0a6a1f1dSLionel Sambuc 		}
62*0a6a1f1dSLionel Sambuc 		free(data);
63*0a6a1f1dSLionel Sambuc 		if (errno == ENOMEM && *len != SIZE_MAX) {
64*0a6a1f1dSLionel Sambuc 			if (*len > SIZE_MAX / 2)
65*0a6a1f1dSLionel Sambuc 				*len = SIZE_MAX;
66*0a6a1f1dSLionel Sambuc 			else
67*0a6a1f1dSLionel Sambuc 				*len *= 2;
68*0a6a1f1dSLionel Sambuc 			data = malloc(*len);
69*0a6a1f1dSLionel Sambuc 			if (data == NULL) {
70*0a6a1f1dSLionel Sambuc 				*len = SIZE_MAX;
71*0a6a1f1dSLionel Sambuc 				return NULL;
72*0a6a1f1dSLionel Sambuc 			}
73*0a6a1f1dSLionel Sambuc 			continue;
74*0a6a1f1dSLionel Sambuc 		}
75*0a6a1f1dSLionel Sambuc 		*len = SIZE_MAX;
76*0a6a1f1dSLionel Sambuc 		return NULL;
77*0a6a1f1dSLionel Sambuc 	}
78*0a6a1f1dSLionel Sambuc }
79*0a6a1f1dSLionel Sambuc 
80*0a6a1f1dSLionel Sambuc void *
asysctlbyname(const char * gname,size_t * len)81*0a6a1f1dSLionel Sambuc asysctlbyname(const char *gname, size_t *len)
82*0a6a1f1dSLionel Sambuc {
83*0a6a1f1dSLionel Sambuc 	int name[CTL_MAXNAME];
84*0a6a1f1dSLionel Sambuc 	u_int namelen;
85*0a6a1f1dSLionel Sambuc 
86*0a6a1f1dSLionel Sambuc 	if (sysctlgetmibinfo(gname, &name[0], &namelen, NULL, NULL, NULL,
87*0a6a1f1dSLionel Sambuc 			     SYSCTL_VERSION)) {
88*0a6a1f1dSLionel Sambuc 		*len = SIZE_MAX;
89*0a6a1f1dSLionel Sambuc 		return NULL;
90*0a6a1f1dSLionel Sambuc 	}
91*0a6a1f1dSLionel Sambuc 	return asysctl(&name[0], namelen, len);
92*0a6a1f1dSLionel Sambuc }
93