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
|
/* ----------------------------------------------------------------------- *
*
* Copyright 2010 Intel Corp. - All Rights Reserved
* Copyright 2015 Paulo Alcantara <pcacjr@zytor.com>
*
* 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, Inc., 53 Temple Place Ste 330,
* Boston MA 02111-1307, USA; either version 2 of the License, or
* (at your option) any later version; incorporated herein by reference.
*
* ----------------------------------------------------------------------- */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>
#include <unistd.h>
#include "syslxrw.h"
static void die(const char *msg)
{
fputs(msg, stderr);
exit(1);
}
/*
* read/write wrapper functions
*/
ssize_t xpread(int fd, void *buf, size_t count, off_t offset)
{
char *bufp = (char *)buf;
ssize_t rv;
ssize_t done = 0;
while (count) {
rv = pread(fd, bufp, count, offset);
if (rv == 0) {
die("short read");
} else if (rv == -1) {
if (errno == EINTR) {
continue;
} else {
die(strerror(errno));
}
} else {
bufp += rv;
offset += rv;
done += rv;
count -= rv;
}
}
return done;
}
ssize_t xpwrite(int fd, const void *buf, size_t count, off_t offset)
{
const char *bufp = (const char *)buf;
ssize_t rv;
ssize_t done = 0;
while (count) {
rv = pwrite(fd, bufp, count, offset);
if (rv == 0) {
die("short write");
} else if (rv == -1) {
if (errno == EINTR) {
continue;
} else {
die(strerror(errno));
}
} else {
bufp += rv;
offset += rv;
done += rv;
count -= rv;
}
}
return done;
}
|
