xref: /dragonfly/lib/libkinfo/kinfo_file.c (revision 0085a56d)
1 /*
2  * Copyright (c) 2004 The DragonFly Project.  All rights reserved.
3  *
4  * This code is derived from software contributed to The DragonFly Project
5  * by Joerg Sonnenberger <joerg@bec.de>.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
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
15  *    the documentation and/or other materials provided with the
16  *    distribution.
17  * 3. Neither the name of The DragonFly Project nor the names of its
18  *    contributors may be used to endorse or promote products derived
19  *    from this software without specific, prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  * $DragonFly: src/lib/libkinfo/kinfo_file.c,v 1.4 2004/12/21 15:07:42 joerg Exp $
35  */
36 
37 #include <sys/kinfo.h>
38 #include <sys/param.h>
39 #include <sys/sysctl.h>
40 
41 #include <err.h>
42 #include <errno.h>
43 #include <kinfo.h>
44 #include <stdlib.h>
45 
46 #define	KERN_FILE_SYSCTL "kern.file"
47 
48 int
49 kinfo_get_files(struct kinfo_file **file_buf, size_t *len)
50 {
51 	int retval;
52 	void *buf;
53 	size_t new_len;
54 
55 	retval = sysctlbyname(KERN_FILE_SYSCTL, NULL, &new_len, NULL, 0);
56 	if (retval)
57 		return(retval);
58 	if ((buf = malloc(new_len)) == NULL)
59 		return(ENOMEM);
60 	retval = sysctlbyname(KERN_FILE_SYSCTL, buf, &new_len, NULL, 0);
61 	if (retval) {
62 		free(buf);
63 		return(retval);
64 	}
65 	/*
66 	 * Shrink the buffer to the minimum size, this is not supposed
67 	 * to fail.
68 	 */
69 	if ((buf = reallocf(buf, new_len)) == NULL)
70 		err(1, "realloc");
71 	if (new_len != 0 &&
72 	    ((struct kinfo_file *)buf)->f_size != sizeof(struct kinfo_file)) {
73 		warnx("kernel size of struct kinfo_file changed");
74 		free(buf);
75 		return(EOPNOTSUPP);
76 	}
77 	*len = new_len / sizeof(struct kinfo_file);
78 	*file_buf = buf;
79 	return(0);
80 }
81 
82 /* XXX convert kern.maxfiles to size_t */
83 int
84 kinfo_get_maxfiles(int *maxfiles)
85 {
86 	size_t len = sizeof(*maxfiles);
87 
88 	return(sysctlbyname("kern.maxfiles", maxfiles, &len, NULL, 0));
89 }
90 
91 /* XXX convert kern.openfiles to size_t */
92 int
93 kinfo_get_openfiles(int *openfiles)
94 {
95 	size_t len = sizeof(*openfiles);
96 
97 	return(sysctlbyname("kern.openfiles", openfiles, &len, NULL, 0));
98 }
99