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
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
|
/* $Id: fileio-at-posix.cpp $ */
/** @file
* IPRT - File I/O, RTFileReadAt and RTFileWriteAt, posix.
*/
/*
* Copyright (C) 2006-2023 Oracle and/or its affiliates.
*
* This file is part of VirtualBox base platform packages, as
* available from https://www.virtualbox.org.
*
* 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, in version 3 of the
* License.
*
* 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, see <https://www.gnu.org/licenses>.
*
* The contents of this file may alternatively be used under the terms
* of the Common Development and Distribution License Version 1.0
* (CDDL), a copy of it is provided in the "COPYING.CDDL" file included
* in the VirtualBox distribution, in which case the provisions of the
* CDDL are applicable instead of those of the GPL.
*
* You may elect to license modified versions of this file under the
* terms and conditions of either the GPL or the CDDL or both.
*
* SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0
*/
/*********************************************************************************************************************************
* Header Files *
*********************************************************************************************************************************/
#include <errno.h>
#include <sys/types.h>
#include <unistd.h>
#include "internal/iprt.h"
#include <iprt/file.h>
#include <iprt/err.h>
#include <iprt/log.h>
RTDECL(int) RTFileReadAt(RTFILE hFile, RTFOFF off, void *pvBuf, size_t cbToRead, size_t *pcbRead)
{
ssize_t cbRead = pread(RTFileToNative(hFile), pvBuf, cbToRead, off);
if (cbRead >= 0)
{
if (pcbRead)
/* caller can handle partial read. */
*pcbRead = cbRead;
else
{
/* Caller expects all to be read. */
while ((ssize_t)cbToRead > cbRead)
{
ssize_t cbReadPart = pread(RTFileToNative(hFile), (char*)pvBuf + cbRead, cbToRead - cbRead, off + cbRead);
if (cbReadPart <= 0)
{
if (cbReadPart == 0)
return VERR_EOF;
return RTErrConvertFromErrno(errno);
}
cbRead += cbReadPart;
}
}
return VINF_SUCCESS;
}
return RTErrConvertFromErrno(errno);
}
RTDECL(int) RTFileWriteAt(RTFILE hFile, RTFOFF off, const void *pvBuf, size_t cbToWrite, size_t *pcbWritten)
{
ssize_t cbWritten = pwrite(RTFileToNative(hFile), pvBuf, cbToWrite, off);
if (cbWritten >= 0)
{
if (pcbWritten)
/* caller can handle partial write. */
*pcbWritten = cbWritten;
else
{
/* Caller expects all to be write. */
while ((ssize_t)cbToWrite > cbWritten)
{
ssize_t cbWrittenPart = pwrite(RTFileToNative(hFile), (const char *)pvBuf + cbWritten, cbToWrite - cbWritten,
off + cbWritten);
if (cbWrittenPart < 0)
return cbWrittenPart < 0 ? RTErrConvertFromErrno(errno) : VERR_TRY_AGAIN;
cbWritten += cbWrittenPart;
}
}
return VINF_SUCCESS;
}
return RTErrConvertFromErrno(errno);
}
|