1 | /* $Id: fileio-at-posix.cpp 98103 2023-01-17 14:15:46Z vboxsync $ */
|
---|
2 | /** @file
|
---|
3 | * IPRT - File I/O, RTFileReadAt and RTFileWriteAt, posix.
|
---|
4 | */
|
---|
5 |
|
---|
6 | /*
|
---|
7 | * Copyright (C) 2006-2023 Oracle and/or its affiliates.
|
---|
8 | *
|
---|
9 | * This file is part of VirtualBox base platform packages, as
|
---|
10 | * available from https://www.virtualbox.org.
|
---|
11 | *
|
---|
12 | * This program is free software; you can redistribute it and/or
|
---|
13 | * modify it under the terms of the GNU General Public License
|
---|
14 | * as published by the Free Software Foundation, in version 3 of the
|
---|
15 | * License.
|
---|
16 | *
|
---|
17 | * This program is distributed in the hope that it will be useful, but
|
---|
18 | * WITHOUT ANY WARRANTY; without even the implied warranty of
|
---|
19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
---|
20 | * General Public License for more details.
|
---|
21 | *
|
---|
22 | * You should have received a copy of the GNU General Public License
|
---|
23 | * along with this program; if not, see <https://www.gnu.org/licenses>.
|
---|
24 | *
|
---|
25 | * The contents of this file may alternatively be used under the terms
|
---|
26 | * of the Common Development and Distribution License Version 1.0
|
---|
27 | * (CDDL), a copy of it is provided in the "COPYING.CDDL" file included
|
---|
28 | * in the VirtualBox distribution, in which case the provisions of the
|
---|
29 | * CDDL are applicable instead of those of the GPL.
|
---|
30 | *
|
---|
31 | * You may elect to license modified versions of this file under the
|
---|
32 | * terms and conditions of either the GPL or the CDDL or both.
|
---|
33 | *
|
---|
34 | * SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0
|
---|
35 | */
|
---|
36 |
|
---|
37 |
|
---|
38 | /*********************************************************************************************************************************
|
---|
39 | * Header Files *
|
---|
40 | *********************************************************************************************************************************/
|
---|
41 | #include <errno.h>
|
---|
42 | #include <sys/types.h>
|
---|
43 | #include <unistd.h>
|
---|
44 |
|
---|
45 | #include "internal/iprt.h"
|
---|
46 | #include <iprt/file.h>
|
---|
47 |
|
---|
48 | #include <iprt/err.h>
|
---|
49 | #include <iprt/log.h>
|
---|
50 |
|
---|
51 |
|
---|
52 |
|
---|
53 | RTDECL(int) RTFileReadAt(RTFILE hFile, RTFOFF off, void *pvBuf, size_t cbToRead, size_t *pcbRead)
|
---|
54 | {
|
---|
55 | ssize_t cbRead = pread(RTFileToNative(hFile), pvBuf, cbToRead, off);
|
---|
56 | if (cbRead >= 0)
|
---|
57 | {
|
---|
58 | if (pcbRead)
|
---|
59 | /* caller can handle partial read. */
|
---|
60 | *pcbRead = cbRead;
|
---|
61 | else
|
---|
62 | {
|
---|
63 | /* Caller expects all to be read. */
|
---|
64 | while ((ssize_t)cbToRead > cbRead)
|
---|
65 | {
|
---|
66 | ssize_t cbReadPart = pread(RTFileToNative(hFile), (char*)pvBuf + cbRead, cbToRead - cbRead, off + cbRead);
|
---|
67 | if (cbReadPart <= 0)
|
---|
68 | {
|
---|
69 | if (cbReadPart == 0)
|
---|
70 | return VERR_EOF;
|
---|
71 | return RTErrConvertFromErrno(errno);
|
---|
72 | }
|
---|
73 | cbRead += cbReadPart;
|
---|
74 | }
|
---|
75 | }
|
---|
76 | return VINF_SUCCESS;
|
---|
77 | }
|
---|
78 |
|
---|
79 | return RTErrConvertFromErrno(errno);
|
---|
80 | }
|
---|
81 |
|
---|
82 |
|
---|
83 | RTDECL(int) RTFileWriteAt(RTFILE hFile, RTFOFF off, const void *pvBuf, size_t cbToWrite, size_t *pcbWritten)
|
---|
84 | {
|
---|
85 | ssize_t cbWritten = pwrite(RTFileToNative(hFile), pvBuf, cbToWrite, off);
|
---|
86 | if (cbWritten >= 0)
|
---|
87 | {
|
---|
88 | if (pcbWritten)
|
---|
89 | /* caller can handle partial write. */
|
---|
90 | *pcbWritten = cbWritten;
|
---|
91 | else
|
---|
92 | {
|
---|
93 | /* Caller expects all to be write. */
|
---|
94 | while ((ssize_t)cbToWrite > cbWritten)
|
---|
95 | {
|
---|
96 | ssize_t cbWrittenPart = pwrite(RTFileToNative(hFile), (const char *)pvBuf + cbWritten, cbToWrite - cbWritten,
|
---|
97 | off + cbWritten);
|
---|
98 | if (cbWrittenPart < 0)
|
---|
99 | return cbWrittenPart < 0 ? RTErrConvertFromErrno(errno) : VERR_TRY_AGAIN;
|
---|
100 | cbWritten += cbWrittenPart;
|
---|
101 | }
|
---|
102 | }
|
---|
103 | return VINF_SUCCESS;
|
---|
104 | }
|
---|
105 | return RTErrConvertFromErrno(errno);
|
---|
106 | }
|
---|
107 |
|
---|