xref: /dragonfly/lib/libkvm/kvm_file.c (revision ae071d8d)
1 /*-
2  * Copyright (c) 1989, 1992, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * @(#)kvm_file.c	8.1 (Berkeley) 6/4/93
30  * $FreeBSD: src/lib/libkvm/kvm_file.c,v 1.11 2000/02/18 16:39:00 peter Exp $
31  */
32 
33 /*
34  * File list interface for kvm.  pstat, fstat and netstat are
35  * users of this code, so we've factored it out into a separate module.
36  * Thus, we keep this grunge out of the other kvm applications (i.e.,
37  * most other applications are interested only in open/close/read/nlist).
38  */
39 
40 #include <sys/user.h>	/* MUST BE FIRST */
41 #include <sys/param.h>
42 #include <sys/proc.h>
43 #define _KERNEL
44 #include <sys/file.h>
45 #undef _KERNEL
46 #include <sys/stat.h>
47 #include <sys/ioctl.h>
48 #include <nlist.h>
49 #include <kvm.h>
50 
51 #include <vm/vm.h>
52 #include <vm/vm_param.h>
53 #include <vm/swap_pager.h>
54 
55 #include <sys/sysctl.h>
56 
57 #include <limits.h>
58 #include <ndbm.h>
59 #include <paths.h>
60 
61 #include "kvm_private.h"
62 
63 #define KREAD(kd, addr, obj) \
64 	(kvm_read(kd, addr, obj, sizeof(*obj)) != sizeof(*obj))
65 
66 /*
67  * Get file structures.
68  */
69 static int
70 kvm_deadfiles(kvm_t *kd, int op, int arg, long filehead_o, int nfiles)
71 {
72 	int buflen = kd->arglen, n = 0;
73 	struct file *fp;
74 	char *where = kd->argspc;
75 	struct filelist filehead;
76 
77 	/*
78 	 * first copyout filehead
79 	 */
80 	if (buflen > sizeof (filehead)) {
81 		if (KREAD(kd, filehead_o, &filehead)) {
82 			_kvm_err(kd, kd->program, "can't read filehead");
83 			return (0);
84 		}
85 		buflen -= sizeof (filehead);
86 		where += sizeof (filehead);
87 		*(struct filelist *)kd->argspc = filehead;
88 	}
89 	/*
90 	 * followed by an array of file structures
91 	 */
92 	for (fp = filehead.lh_first; fp != NULL; fp = fp->f_list.le_next) {
93 		if (buflen > sizeof (struct file)) {
94 			if (KREAD(kd, (long)fp, ((struct file *)where))) {
95 				_kvm_err(kd, kd->program, "can't read kfp");
96 				return (0);
97 			}
98 			buflen -= sizeof (struct file);
99 			fp = (struct file *)where;
100 			where += sizeof (struct file);
101 			n++;
102 		}
103 	}
104 	if (n != nfiles) {
105 		_kvm_err(kd, kd->program, "inconsistent nfiles");
106 		return (0);
107 	}
108 	return (nfiles);
109 }
110 
111 char *
112 kvm_getfiles(kvm_t *kd, int op, int arg, int *cnt)
113 {
114 	int mib[2], st, nfiles;
115 	size_t size;
116 	struct file *fp, *fplim;
117 	struct filelist filehead;
118 
119 	if (kvm_ishost(kd)) {
120 		size = 0;
121 		mib[0] = CTL_KERN;
122 		mib[1] = KERN_FILE;
123 		st = sysctl(mib, 2, NULL, &size, NULL, 0);
124 		if (st == -1) {
125 			_kvm_syserr(kd, kd->program, "kvm_getfiles");
126 			return (0);
127 		}
128 		if (kd->argspc == 0)
129 			kd->argspc = (char *)_kvm_malloc(kd, size);
130 		else if (kd->arglen < size)
131 			kd->argspc = (char *)_kvm_realloc(kd, kd->argspc, size);
132 		if (kd->argspc == 0)
133 			return (0);
134 		kd->arglen = size;
135 		st = sysctl(mib, 2, kd->argspc, &size, NULL, 0);
136 		if (st == -1 || size < sizeof(filehead)) {
137 			_kvm_syserr(kd, kd->program, "kvm_getfiles");
138 			return (0);
139 		}
140 		filehead = *(struct filelist *)kd->argspc;
141 		fp = (struct file *)(kd->argspc + sizeof (filehead));
142 		fplim = (struct file *)(kd->argspc + size);
143 		for (nfiles = 0; filehead.lh_first && (fp < fplim); nfiles++, fp++)
144 			filehead.lh_first = fp->f_list.le_next;
145 	} else {
146 		struct nlist nl[3], *p;
147 
148 		nl[0].n_name = "_filehead";
149 		nl[1].n_name = "_nfiles";
150 		nl[2].n_name = 0;
151 
152 		if (kvm_nlist(kd, nl) != 0) {
153 			for (p = nl; p->n_type != 0; ++p)
154 				;
155 			_kvm_err(kd, kd->program,
156 				 "%s: no such symbol", p->n_name);
157 			return (0);
158 		}
159 		if (KREAD(kd, nl[0].n_value, &nfiles)) {
160 			_kvm_err(kd, kd->program, "can't read nfiles");
161 			return (0);
162 		}
163 		size = sizeof(filehead) + (nfiles + 10) * sizeof(struct file);
164 		if (kd->argspc == 0)
165 			kd->argspc = (char *)_kvm_malloc(kd, size);
166 		else if (kd->arglen < size)
167 			kd->argspc = (char *)_kvm_realloc(kd, kd->argspc, size);
168 		if (kd->argspc == 0)
169 			return (0);
170 		kd->arglen = size;
171 		nfiles = kvm_deadfiles(kd, op, arg, nl[1].n_value, nfiles);
172 		if (nfiles == 0)
173 			return (0);
174 	}
175 	*cnt = nfiles;
176 	return (kd->argspc);
177 }
178