1 /*
2 This file is part of the Okteta Kasten module, made within the KDE community.
3
4 SPDX-FileCopyrightText: 2009-2010 Friedrich W. H. Kossebau <kossebau@kde.org>
5
6 SPDX-License-Identifier: LGPL-2.1-only OR LGPL-3.0-only OR LicenseRef-KDE-Accepted-LGPL
7 */
8
9 #include "bytearraybase64streamencoder.hpp"
10
11 // Okteta core
12 #include <Okteta/AbstractByteArrayModel>
13 // KF
14 #include <KLocalizedString>
15 // Qt
16 #include <QTextStream>
17
18 namespace Kasten {
19
20 const char base64EncodeMap[64] = {
21 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H',
22 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
23 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X',
24 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f',
25 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n',
26 'o', 'p', 'q', 'r', 's', 't', 'u', 'v',
27 'w', 'x', 'y', 'z', '0', '1', '2', '3',
28 '4', '5', '6', '7', '8', '9', '+', '/'
29 };
30
31 static constexpr const char* base64PaddingData[2] = {
32 "==",
33 "="
34 };
base64Padding(ByteArrayBase64StreamEncoder::InputByteIndex index)35 static inline constexpr const char* base64Padding(ByteArrayBase64StreamEncoder::InputByteIndex index)
36 {
37 return base64PaddingData[static_cast<int>(index) - 1];
38 }
39
ByteArrayBase64StreamEncoder()40 ByteArrayBase64StreamEncoder::ByteArrayBase64StreamEncoder()
41 : AbstractByteArrayStreamEncoder(i18nc("name of the encoding target", "Base64"), QStringLiteral("application/base64"))
42 {}
43
44 ByteArrayBase64StreamEncoder::~ByteArrayBase64StreamEncoder() = default;
45
encodeDataToStream(QIODevice * device,const ByteArrayView * byteArrayView,const Okteta::AbstractByteArrayModel * byteArrayModel,const Okteta::AddressRange & range)46 bool ByteArrayBase64StreamEncoder::encodeDataToStream(QIODevice* device,
47 const ByteArrayView* byteArrayView,
48 const Okteta::AbstractByteArrayModel* byteArrayModel,
49 const Okteta::AddressRange& range)
50 {
51 Q_UNUSED(byteArrayView);
52
53 bool success = true;
54
55 // encode
56 QTextStream textStream(device);
57
58 // prepare
59 InputByteIndex inputByteIndex = InputByteIndex::First;
60 int outputGroupsPerLine = 0;
61 unsigned char bitsFromLastByte;
62
63 for (Okteta::Address i = range.start(); i <= range.end(); ++i) {
64 const Okteta::Byte byte = byteArrayModel->byte(i);
65
66 switch (inputByteIndex)
67 {
68 case InputByteIndex::First:
69 // bits 7..2
70 textStream << base64EncodeMap[(byte >> 2)];
71 // bits 1..0 -> 5..4 for next
72 bitsFromLastByte = (byte & 0x3) << 4;
73 inputByteIndex = InputByteIndex::Second;
74 break;
75 case InputByteIndex::Second:
76 // from last and bits 7..4 as 3..0 from this
77 textStream << base64EncodeMap[(bitsFromLastByte | byte >> 4)];
78 // bits 3..0 -> 5..2 for next
79 bitsFromLastByte = (byte & 0xf) << 2;
80 inputByteIndex = InputByteIndex::Third;
81 break;
82 case InputByteIndex::Third:
83 // from last and bits 7..6 as 1..0 from this
84 textStream << base64EncodeMap[(bitsFromLastByte | byte >> 6)];
85 // bits 5..0
86 textStream << base64EncodeMap[(byte & 0x3F)];
87 inputByteIndex = InputByteIndex::First;
88 ++outputGroupsPerLine;
89 if (outputGroupsPerLine >= maxOutputGroupsPerLine && i < range.end()) {
90 textStream << "\r\n";
91 outputGroupsPerLine = 0;
92 }
93 break;
94 }
95 }
96
97 const bool hasBitsLeft = (inputByteIndex != InputByteIndex::First);
98 if (hasBitsLeft) {
99 textStream << base64EncodeMap[bitsFromLastByte]
100 << base64Padding(inputByteIndex);
101 }
102
103 return success;
104 }
105
106 }
107