1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
|
/* $NetBSD$ */
/*
* File "uio.c" is part of the UDFclient toolkit.
* File $Id: uio.c,v 1.7 2011/02/01 20:43:41 reinoud Exp $ $Name: $
*
* Copyright (c) 2004, 2005, 2006, 2011
* Reinoud Zandijk <reinoud@netbsd.org>
* All rights reserved.
*
* The UDFclient toolkit is distributed under the Clarified Artistic Licence.
* A copy of the licence is included in the distribution as
* `LICENCE.clearified.artistic' and a copy of the licence can also be
* requested at the GNU foundantion's website.
*
* Visit the UDFclient toolkit homepage http://www.13thmonkey.org/udftoolkit/
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
#include <assert.h>
#include <string.h>
#include "uio.h"
/* modelled after NetBSD's uiomove */
int uiomove(void *buf, size_t amount, struct uio *uio) {
struct iovec *iov;
char *cp = buf;
size_t cnt;
assert(buf);
assert(uio);
assert(uio->uio_iov);
while (amount > 0 && uio->uio_resid > 0) {
iov = uio->uio_iov;
cnt = iov->iov_len;
if (cnt == 0) {
assert(uio->uio_iovcnt > 0);
uio->uio_iov++;
uio->uio_iovcnt--;
if (uio->uio_iovcnt == 0) return 0; /* end of buffers */
continue;
}
/* not more than requested please */
if (cnt > amount) cnt = amount;
/* move the information */
if (uio->uio_rw == UIO_READ) {
/* read into the uio */
memcpy(cp, iov->iov_base, cnt);
} else {
/* write from the uio */
memcpy(iov->iov_base, cp, cnt);
}
/* update the uio structure to reflect move */
iov->iov_base = (caddr_t) iov->iov_base + cnt;
iov->iov_len -= cnt;
uio->uio_resid -= cnt;
uio->uio_offset += cnt;
cp += cnt;
assert(cnt <= amount);
amount -= cnt;
}
return 0;
}
/* end of uio.c */
|
