xref: /openbsd/share/man/man9/copy.9 (revision 9490d37c)
1.\"	$OpenBSD: copy.9,v 1.14 2007/05/31 19:20:00 jmc Exp $
2.\"	$NetBSD: copy.9,v 1.2 1996/01/09 03:23:04 thorpej Exp $
3.\"
4.\" Copyright (c) 1996 Jason R. Thorpe.
5.\" All rights reserved.
6.\"
7.\" This code is derived from software contributed by Kenneth Stailey.
8.\"
9.\" Redistribution and use in source and binary forms, with or without
10.\" modification, are permitted provided that the following conditions
11.\" are met:
12.\" 1. Redistributions of source code must retain the above copyright
13.\"    notice, this list of conditions and the following disclaimer.
14.\" 2. Redistributions in binary form must reproduce the above copyright
15.\"    notice, this list of conditions and the following disclaimer in the
16.\"    documentation and/or other materials provided with the distribution.
17.\" 3. All advertising materials mentioning features or use of this software
18.\"    must display the following acknowledgement:
19.\"	This product includes software developed for the NetBSD Project
20.\"	by Jason R. Thorpe.
21.\" 4. The name of the author may not be used to endorse or promote products
22.\"    derived from this software without specific prior written permission.
23.\"
24.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
25.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
26.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
27.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
28.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
29.\" BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
30.\" LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
31.\" AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
32.\" OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34.\" SUCH DAMAGE.
35.\"
36.Dd $Mdocdate: May 31 2007 $
37.Dt COPY 9
38.Os
39.Sh NAME
40.Nm copy
41.Nd kernel copy functions
42.Sh SYNOPSIS
43.Fd #include <sys/types.h>
44.Fd #include <sys/systm.h>
45.Ft int
46.Fn copyin "const void *uaddr" "void *kaddr" "size_t len"
47.Ft int
48.Fn copyout "const void *kaddr" "void *uaddr" "size_t len"
49.Ft int
50.Fn copystr "const void *kfaddr" "void *kdaddr" "size_t len" "size_t *done"
51.Ft int
52.Fn copyinstr "const void *uaddr" "void *kaddr" "size_t len" "size_t *done"
53.Ft int
54.Fn copyoutstr "const void *kaddr" "void *uaddr" "size_t len" "size_t *done"
55.Sh DESCRIPTION
56The
57.Nm
58functions are designed to copy contiguous data from one address to another.
59All but
60.Fn copystr
61copy data from user-space to kernel-space or vice-versa.
62.Pp
63The
64.Nm
65routines provide the following functionality:
66.Bl -tag -width "copyoutstr()"
67.It Fn copyin
68Copies
69.Fa len
70bytes of data from the user-space address
71.Fa uaddr
72to the kernel-space address
73.Fa kaddr .
74.It Fn copyout
75Copies
76.Fa len
77bytes of data from the kernel-space address
78.Fa kaddr
79to the user-space address
80.Fa uaddr .
81.It Fn copystr
82Copies a null-terminated string, at most
83.Fa len
84bytes long, from kernel-space address
85.Fa kfaddr
86to kernel-space address
87.Fa kdaddr .
88The number of bytes actually copied, including the terminating null,
89is returned in
90.Fa *done ,
91if
92.Fa done
93is not
94.Dv NULL .
95.It Fn copyinstr
96Copies a null-terminated string, at most
97.Fa len
98bytes long, from user-space address
99.Fa uaddr
100to kernel-space address
101.Fa kaddr .
102The number of bytes actually copied, including the terminating null,
103is returned in
104.Fa *done ,
105if
106.Fa done
107is not
108.Dv NULL .
109.It Fn copyoutstr
110Copies a null-terminated string, at most
111.Fa len
112bytes long, from kernel-space address
113.Fa kaddr
114to user-space address
115.Fa uaddr .
116The number of bytes actually copied, including the terminating null,
117is returned in
118.Fa *done ,
119if
120.Fa done
121is not
122.Dv NULL .
123.El
124.Sh RETURN VALUES
125The
126.Nm
127functions return 0 on success or
128.Er EFAULT
129if a bad address is encountered.
130In addition, the
131.Fn copystr ,
132.Fn copyinstr ,
133and
134.Fn copyoutstr
135functions return
136.Er ENAMETOOLONG
137if the string is longer than
138.Fa len
139bytes.
140.\" .Sh SEE ALSO
141