1/*
2 * Copyright (c) 2008, 2009, Google Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are
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7 *
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9 * notice, this list of conditions and the following disclaimer.
10 * * Redistributions in binary form must reproduce the above
11 * copyright notice, this list of conditions and the following disclaimer
12 * in the documentation and/or other materials provided with the
13 * distribution.
14 * * Neither the name of Google Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived from
16 * this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#pragma once
32
33#include "BMPImageReader.h"
34
35namespace WebCore {
36
37// This class decodes the ICO and CUR image formats.
38class ICOImageDecoder final : public ScalableImageDecoder {
39public:
40 static Ref<ScalableImageDecoder> create(AlphaOption alphaOption, GammaAndColorProfileOption gammaAndColorProfileOption)
41 {
42 return adoptRef(*new ICOImageDecoder(alphaOption, gammaAndColorProfileOption));
43 }
44
45 virtual ~ICOImageDecoder();
46
47 // ScalableImageDecoder
48 String filenameExtension() const final { return "ico"_s; }
49 void setData(SharedBuffer&, bool allDataReceived) final;
50 IntSize size() const final;
51 IntSize frameSizeAtIndex(size_t, SubsamplingLevel) const final;
52 bool setSize(const IntSize&) final;
53 size_t frameCount() const final;
54 ScalableImageDecoderFrame* frameBufferAtIndex(size_t) final;
55 // CAUTION: setFailed() deletes all readers and decoders. Be careful to
56 // avoid accessing deleted memory, especially when calling this from
57 // inside BMPImageReader!
58 bool setFailed() final;
59 Optional<IntPoint> hotSpot() const final;
60
61private:
62 enum ImageType {
63 Unknown,
64 BMP,
65 PNG,
66 };
67
68 enum FileType {
69 ICON = 1,
70 CURSOR = 2,
71 };
72
73 struct IconDirectoryEntry {
74 IntSize m_size;
75 uint16_t m_bitCount;
76 IntPoint m_hotSpot;
77 uint32_t m_imageOffset;
78 };
79
80 ICOImageDecoder(AlphaOption, GammaAndColorProfileOption);
81 void tryDecodeSize(bool allDataReceived) final { decode(0, true, allDataReceived); }
82
83 // Returns true if |a| is a preferable icon entry to |b|.
84 // Larger sizes, or greater bitdepths at the same size, are preferable.
85 static bool compareEntries(const IconDirectoryEntry& a, const IconDirectoryEntry& b);
86
87 inline uint16_t readUint16(int offset) const
88 {
89 return BMPImageReader::readUint16(m_data.get(), m_decodedOffset + offset);
90 }
91
92 inline uint32_t readUint32(int offset) const
93 {
94 return BMPImageReader::readUint32(m_data.get(), m_decodedOffset + offset);
95 }
96
97 // If the desired PNGImageDecoder exists, gives it the appropriate data.
98 void setDataForPNGDecoderAtIndex(size_t);
99
100 // Decodes the entry at |index|. If |onlySize| is true, stops decoding
101 // after calculating the image size. If decoding fails but there is no
102 // more data coming, sets the "decode failure" flag.
103 void decode(size_t index, bool onlySize, bool allDataReceived);
104
105 // Decodes the directory and directory entries at the beginning of the
106 // data, and initializes members. Returns true if all decoding
107 // succeeded. Once this returns true, all entries' sizes are known.
108 bool decodeDirectory();
109
110 // Decodes the specified entry.
111 bool decodeAtIndex(size_t);
112
113 // Processes the ICONDIR at the beginning of the data. Returns true if
114 // the directory could be decoded.
115 bool processDirectory();
116
117 // Processes the ICONDIRENTRY records after the directory. Keeps the
118 // "best" entry as the one we'll decode. Returns true if the entries
119 // could be decoded.
120 bool processDirectoryEntries();
121
122 // Returns the hot-spot for |index|, returns WTF::nullopt if there is none.
123 Optional<IntPoint> hotSpotAtIndex(size_t) const;
124
125 // Reads and returns a directory entry from the current offset into
126 // |data|.
127 IconDirectoryEntry readDirectoryEntry();
128
129 // Determines whether the desired entry is a BMP or PNG. Returns true
130 // if the type could be determined.
131 ImageType imageTypeAtIndex(size_t);
132
133 // An index into |m_data| representing how much we've already decoded.
134 // Note that this only tracks data _this_ class decodes; once the
135 // BMPImageReader takes over this will not be updated further.
136 size_t m_decodedOffset;
137
138 // Which type of file (ICO/CUR) this is.
139 FileType m_fileType;
140
141 // The headers for the ICO.
142 typedef Vector<IconDirectoryEntry> IconDirectoryEntries;
143 IconDirectoryEntries m_dirEntries;
144
145 // The image decoders for the various frames.
146 typedef Vector<std::unique_ptr<BMPImageReader>> BMPReaders;
147 BMPReaders m_bmpReaders;
148 typedef Vector<RefPtr<ScalableImageDecoder>> PNGDecoders;
149 PNGDecoders m_pngDecoders;
150
151 // Valid only while a BMPImageReader is decoding, this holds the size
152 // for the particular entry being decoded.
153 IntSize m_frameSize;
154};
155
156} // namespace WebCore
157