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
|
/* libguestfs - the guestfsd daemon
* Copyright (C) 2009 Red Hat Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <unistd.h>
#include "daemon.h"
#include "actions.h"
int
do_zero (const char *device)
{
int fd, i;
char buf[4096];
fd = open (device, O_WRONLY);
if (fd == -1) {
reply_with_perror ("%s", device);
return -1;
}
memset (buf, 0, sizeof buf);
int err = 0;
int saved_errno = 0;
for (i = 0; i < 32; ++i)
if (write (fd, buf, sizeof buf) != sizeof buf) {
saved_errno = errno;
err = -1;
}
if (close (fd) && saved_errno == 0) {
saved_errno = errno;
err = -1;
}
if (saved_errno)
errno = saved_errno;
return err;
}
|
