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
6 * met:
7 *
8 * * Redistributions of source code must retain the above copyright
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
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#include "config.h"
32#include "BMPImageDecoder.h"
33
34#include "BMPImageReader.h"
35
36namespace WebCore {
37
38// Number of bits in .BMP used to store the file header (doesn't match
39// "sizeof(BMPImageDecoder::BitmapFileHeader)" since we omit some fields and
40// don't pack).
41static const size_t sizeOfFileHeader = 14;
42
43BMPImageDecoder::BMPImageDecoder(AlphaOption alphaOption, GammaAndColorProfileOption gammaAndColorProfileOption)
44 : ScalableImageDecoder(alphaOption, gammaAndColorProfileOption)
45 , m_decodedOffset(0)
46{
47}
48
49void BMPImageDecoder::setData(SharedBuffer& data, bool allDataReceived)
50{
51 if (failed())
52 return;
53
54 ScalableImageDecoder::setData(data, allDataReceived);
55 if (m_reader)
56 m_reader->setData(&data);
57}
58
59ScalableImageDecoderFrame* BMPImageDecoder::frameBufferAtIndex(size_t index)
60{
61 if (index)
62 return 0;
63
64 if (m_frameBufferCache.isEmpty())
65 m_frameBufferCache.grow(1);
66
67 auto* buffer = &m_frameBufferCache.first();
68 if (!buffer->isComplete())
69 decode(false, isAllDataReceived());
70 return buffer;
71}
72
73bool BMPImageDecoder::setFailed()
74{
75 m_reader = nullptr;
76 return ScalableImageDecoder::setFailed();
77}
78
79void BMPImageDecoder::decode(bool onlySize, bool allDataReceived)
80{
81 if (failed())
82 return;
83
84 // If we couldn't decode the image but we've received all the data, decoding
85 // has failed.
86 if (!decodeHelper(onlySize) && allDataReceived)
87 setFailed();
88 // If we're done decoding the image, we don't need the BMPImageReader
89 // anymore. (If we failed, |m_reader| has already been cleared.)
90 else if (!m_frameBufferCache.isEmpty() && m_frameBufferCache.first().isComplete())
91 m_reader = nullptr;
92}
93
94bool BMPImageDecoder::decodeHelper(bool onlySize)
95{
96 size_t imgDataOffset = 0;
97 if ((m_decodedOffset < sizeOfFileHeader) && !processFileHeader(&imgDataOffset))
98 return false;
99
100 if (!m_reader) {
101 m_reader = std::make_unique<BMPImageReader>(this, m_decodedOffset, imgDataOffset, false);
102 m_reader->setData(m_data.get());
103 }
104
105 if (!m_frameBufferCache.isEmpty())
106 m_reader->setBuffer(&m_frameBufferCache.first());
107
108 return m_reader->decodeBMP(onlySize);
109}
110
111bool BMPImageDecoder::processFileHeader(size_t* imgDataOffset)
112{
113 ASSERT(imgDataOffset);
114
115 // Read file header.
116 ASSERT(!m_decodedOffset);
117 if (m_data->size() < sizeOfFileHeader)
118 return false;
119 const uint16_t fileType = (m_data->data()[0] << 8) | static_cast<uint8_t>(m_data->data()[1]);
120 *imgDataOffset = readUint32(10);
121 m_decodedOffset = sizeOfFileHeader;
122
123 // See if this is a bitmap filetype we understand.
124 enum {
125 BMAP = 0x424D, // "BM"
126 // The following additional OS/2 2.x header values (see
127 // http://www.fileformat.info/format/os2bmp/egff.htm ) aren't widely
128 // decoded, and are unlikely to be in much use.
129 /*
130 ICON = 0x4943, // "IC"
131 POINTER = 0x5054, // "PT"
132 COLORICON = 0x4349, // "CI"
133 COLORPOINTER = 0x4350, // "CP"
134 BITMAPARRAY = 0x4241, // "BA"
135 */
136 };
137 return (fileType == BMAP) || setFailed();
138}
139
140} // namespace WebCore
141