1 | /* This file is part of the KDE libraries |
2 | SPDX-FileCopyrightText: 2001, 2002, 2007 David Faure <faure@kde.org> |
3 | |
4 | SPDX-License-Identifier: LGPL-2.0-or-later |
5 | */ |
6 | |
7 | #include "klimitediodevice_p.h" |
8 | #include "loggingcategory.h" |
9 | |
10 | KLimitedIODevice::KLimitedIODevice(QIODevice *dev, qint64 start, qint64 length) |
11 | : m_dev(dev) |
12 | , m_start(start) |
13 | , m_length(length) |
14 | { |
15 | // qCDebug(KArchiveLog) << "start=" << start << "length=" << length; |
16 | open(m: QIODevice::ReadOnly); // krazy:exclude=syscalls |
17 | } |
18 | |
19 | bool KLimitedIODevice::open(QIODevice::OpenMode m) |
20 | { |
21 | // qCDebug(KArchiveLog) << "m=" << m; |
22 | if (m & QIODevice::ReadOnly) { |
23 | /*bool ok = false; |
24 | if ( m_dev->isOpen() ) |
25 | ok = ( m_dev->mode() == QIODevice::ReadOnly ); |
26 | else |
27 | ok = m_dev->open( m ); |
28 | if ( ok )*/ |
29 | m_dev->seek(pos: m_start); // No concurrent access ! |
30 | } else { |
31 | // qCWarning(KArchiveLog) << "KLimitedIODevice::open only supports QIODevice::ReadOnly!"; |
32 | } |
33 | setOpenMode(QIODevice::ReadOnly); |
34 | return true; |
35 | } |
36 | |
37 | void KLimitedIODevice::close() |
38 | { |
39 | } |
40 | |
41 | qint64 KLimitedIODevice::size() const |
42 | { |
43 | return m_length; |
44 | } |
45 | |
46 | qint64 KLimitedIODevice::readData(char *data, qint64 maxlen) |
47 | { |
48 | maxlen = qMin(a: maxlen, b: m_length - pos()); // Apply upper limit |
49 | return m_dev->read(data, maxlen); |
50 | } |
51 | |
52 | bool KLimitedIODevice::seek(qint64 pos) |
53 | { |
54 | Q_ASSERT(pos <= m_length); |
55 | pos = qMin(a: pos, b: m_length); // Apply upper limit |
56 | bool ret = m_dev->seek(pos: m_start + pos); |
57 | if (ret) { |
58 | QIODevice::seek(pos); |
59 | } |
60 | return ret; |
61 | } |
62 | |
63 | qint64 KLimitedIODevice::bytesAvailable() const |
64 | { |
65 | return QIODevice::bytesAvailable(); |
66 | } |
67 | |
68 | bool KLimitedIODevice::isSequential() const |
69 | { |
70 | return m_dev->isSequential(); |
71 | } |
72 | |
73 | #include "moc_klimitediodevice_p.cpp" |
74 | |