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
88
89
90
91
92
|
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
/* Copyright (c) 1988 AT&T */
/* All Rights Reserved */
/*
* ftruncate() and truncate() set a file to a specified
* length using fcntl(F_FREESP) system call. If the file
* was previously longer than length, the bytes past the
* length will no longer be accessible. If it was shorter,
* bytes not written will be zero filled.
*/
#include <sys/feature_tests.h>
#if !defined(_LP64) && _FILE_OFFSET_BITS == 64
#pragma weak ftruncate64 = _ftruncate64
#pragma weak truncate64 = _truncate64
#define _ftruncate _ftruncate64
#define _truncate _truncate64
#else /* !_LP64 && _FILE_OFFSET_BITS == 64 */
#pragma weak ftruncate = _ftruncate
#pragma weak truncate = _truncate
#endif /* !_LP64 && _FILE_OFFSET_BITS == 64 */
#include "synonyms.h"
#include <unistd.h>
#include <stdio.h>
#include <fcntl.h>
#include <sys/types.h>
int
_ftruncate(int fildes, off_t len)
{
struct flock lck;
lck.l_whence = 0; /* offset l_start from beginning of file */
lck.l_start = len;
lck.l_type = F_WRLCK; /* setting a write lock */
lck.l_len = (off_t)0; /* until the end of the file address space */
if (fcntl(fildes, F_FREESP, &lck) == -1) {
return (-1);
}
return (0);
}
int
_truncate(const char *path, off_t len)
{
int fd;
if ((fd = open(path, O_WRONLY)) == -1) {
return (-1);
}
if (ftruncate(fd, len) == -1) {
(void) close(fd);
return (-1);
}
(void) close(fd);
return (0);
}
|
