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 "platform/image-decoders/bmp/BMPImageDecoder.h"
33
34#include "platform/PlatformInstrumentation.h"
35#include "wtf/PassOwnPtr.h"
36
37namespace blink {
38
39// Number of bits in .BMP used to store the file header (doesn't match
40// "sizeof(BMPImageDecoder::BitmapFileHeader)" since we omit some fields and
41// don't pack).
42static const size_t sizeOfFileHeader = 14;
43
44BMPImageDecoder::BMPImageDecoder(ImageSource::AlphaOption alphaOption,
45    ImageSource::GammaAndColorProfileOption gammaAndColorProfileOption,
46    size_t maxDecodedBytes)
47    : ImageDecoder(alphaOption, gammaAndColorProfileOption, maxDecodedBytes)
48    , m_decodedOffset(0)
49{
50}
51
52void BMPImageDecoder::setData(SharedBuffer* data, bool allDataReceived)
53{
54    if (failed())
55        return;
56
57    ImageDecoder::setData(data, allDataReceived);
58    if (m_reader)
59        m_reader->setData(data);
60}
61
62bool BMPImageDecoder::isSizeAvailable()
63{
64    if (!ImageDecoder::isSizeAvailable())
65        decode(true);
66
67    return ImageDecoder::isSizeAvailable();
68}
69
70ImageFrame* BMPImageDecoder::frameBufferAtIndex(size_t index)
71{
72    if (index)
73        return 0;
74
75    if (m_frameBufferCache.isEmpty()) {
76        m_frameBufferCache.resize(1);
77        m_frameBufferCache.first().setPremultiplyAlpha(m_premultiplyAlpha);
78    }
79
80    ImageFrame* buffer = &m_frameBufferCache.first();
81    if (buffer->status() != ImageFrame::FrameComplete) {
82        PlatformInstrumentation::willDecodeImage("BMP");
83        decode(false);
84        PlatformInstrumentation::didDecodeImage();
85    }
86    return buffer;
87}
88
89bool BMPImageDecoder::setFailed()
90{
91    m_reader.clear();
92    return ImageDecoder::setFailed();
93}
94
95void BMPImageDecoder::decode(bool onlySize)
96{
97    if (failed())
98        return;
99
100    // If we couldn't decode the image but we've received all the data, decoding
101    // has failed.
102    if (!decodeHelper(onlySize) && isAllDataReceived())
103        setFailed();
104    // If we're done decoding the image, we don't need the BMPImageReader
105    // anymore.  (If we failed, |m_reader| has already been cleared.)
106    else if (!m_frameBufferCache.isEmpty() && (m_frameBufferCache.first().status() == ImageFrame::FrameComplete))
107        m_reader.clear();
108}
109
110bool BMPImageDecoder::decodeHelper(bool onlySize)
111{
112    size_t imgDataOffset = 0;
113    if ((m_decodedOffset < sizeOfFileHeader) && !processFileHeader(imgDataOffset))
114        return false;
115
116    if (!m_reader) {
117        m_reader = adoptPtr(new BMPImageReader(this, m_decodedOffset, imgDataOffset, false));
118        m_reader->setData(m_data.get());
119    }
120
121    if (!m_frameBufferCache.isEmpty())
122        m_reader->setBuffer(&m_frameBufferCache.first());
123
124    return m_reader->decodeBMP(onlySize);
125}
126
127bool BMPImageDecoder::processFileHeader(size_t& imgDataOffset)
128{
129    // Read file header.
130    ASSERT(!m_decodedOffset);
131    if (m_data->size() < sizeOfFileHeader)
132        return false;
133    const uint16_t fileType = (m_data->data()[0] << 8) | static_cast<uint8_t>(m_data->data()[1]);
134    imgDataOffset = readUint32(10);
135    m_decodedOffset = sizeOfFileHeader;
136
137    // See if this is a bitmap filetype we understand.
138    enum {
139        BMAP = 0x424D,  // "BM"
140        // The following additional OS/2 2.x header values (see
141        // http://www.fileformat.info/format/os2bmp/egff.htm ) aren't widely
142        // decoded, and are unlikely to be in much use.
143        /*
144        ICON = 0x4943,  // "IC"
145        POINTER = 0x5054,  // "PT"
146        COLORICON = 0x4349,  // "CI"
147        COLORPOINTER = 0x4350,  // "CP"
148        BITMAPARRAY = 0x4241,  // "BA"
149        */
150    };
151    return (fileType == BMAP) || setFailed();
152}
153
154} // namespace blink
155