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/ico/ICOImageDecoder.h" 33 34#include <algorithm> 35 36#include "platform/PlatformInstrumentation.h" 37#include "platform/image-decoders/png/PNGImageDecoder.h" 38#include "wtf/PassOwnPtr.h" 39 40namespace WebCore { 41 42// Number of bits in .ICO/.CUR used to store the directory and its entries, 43// respectively (doesn't match sizeof values for member structs since we omit 44// some fields). 45static const size_t sizeOfDirectory = 6; 46static const size_t sizeOfDirEntry = 16; 47 48ICOImageDecoder::ICOImageDecoder(ImageSource::AlphaOption alphaOption, 49 ImageSource::GammaAndColorProfileOption gammaAndColorProfileOption, 50 size_t maxDecodedBytes) 51 : ImageDecoder(alphaOption, gammaAndColorProfileOption, maxDecodedBytes) 52 , m_decodedOffset(0) 53{ 54} 55 56ICOImageDecoder::~ICOImageDecoder() 57{ 58} 59 60void ICOImageDecoder::setData(SharedBuffer* data, bool allDataReceived) 61{ 62 if (failed()) 63 return; 64 65 ImageDecoder::setData(data, allDataReceived); 66 67 for (BMPReaders::iterator i(m_bmpReaders.begin()); i != m_bmpReaders.end(); ++i) { 68 if (*i) 69 (*i)->setData(data); 70 } 71 for (size_t i = 0; i < m_pngDecoders.size(); ++i) 72 setDataForPNGDecoderAtIndex(i); 73} 74 75bool ICOImageDecoder::isSizeAvailable() 76{ 77 if (!ImageDecoder::isSizeAvailable()) 78 decode(0, true); 79 80 return ImageDecoder::isSizeAvailable(); 81} 82 83IntSize ICOImageDecoder::size() const 84{ 85 return m_frameSize.isEmpty() ? ImageDecoder::size() : m_frameSize; 86} 87 88IntSize ICOImageDecoder::frameSizeAtIndex(size_t index) const 89{ 90 return (index && (index < m_dirEntries.size())) ? m_dirEntries[index].m_size : size(); 91} 92 93bool ICOImageDecoder::setSize(unsigned width, unsigned height) 94{ 95 // The size calculated inside the BMPImageReader had better match the one in 96 // the icon directory. 97 return m_frameSize.isEmpty() ? ImageDecoder::setSize(width, height) : ((IntSize(width, height) == m_frameSize) || setFailed()); 98} 99 100size_t ICOImageDecoder::frameCount() 101{ 102 decode(0, true); 103 if (m_frameBufferCache.isEmpty()) { 104 m_frameBufferCache.resize(m_dirEntries.size()); 105 for (size_t i = 0; i < m_dirEntries.size(); ++i) { 106 m_frameBufferCache[i].setPremultiplyAlpha(m_premultiplyAlpha); 107 m_frameBufferCache[i].setRequiredPreviousFrameIndex(kNotFound); 108 } 109 } 110 // CAUTION: We must not resize m_frameBufferCache again after this, as 111 // decodeAtIndex() may give a BMPImageReader a pointer to one of the 112 // entries. 113 return m_frameBufferCache.size(); 114} 115 116ImageFrame* ICOImageDecoder::frameBufferAtIndex(size_t index) 117{ 118 // Ensure |index| is valid. 119 if (index >= frameCount()) 120 return 0; 121 122 ImageFrame* buffer = &m_frameBufferCache[index]; 123 if (buffer->status() != ImageFrame::FrameComplete) { 124 PlatformInstrumentation::willDecodeImage("ICO"); 125 decode(index, false); 126 PlatformInstrumentation::didDecodeImage(); 127 } 128 return buffer; 129} 130 131bool ICOImageDecoder::setFailed() 132{ 133 m_bmpReaders.clear(); 134 m_pngDecoders.clear(); 135 return ImageDecoder::setFailed(); 136} 137 138bool ICOImageDecoder::hotSpot(IntPoint& hotSpot) const 139{ 140 // When unspecified, the default frame is always frame 0. This is consistent with 141 // BitmapImage where currentFrame() starts at 0 and only increases when animation is 142 // requested. 143 return hotSpotAtIndex(0, hotSpot); 144} 145 146bool ICOImageDecoder::hotSpotAtIndex(size_t index, IntPoint& hotSpot) const 147{ 148 if (index >= m_dirEntries.size() || m_fileType != CURSOR) 149 return false; 150 151 hotSpot = m_dirEntries[index].m_hotSpot; 152 return true; 153} 154 155 156// static 157bool ICOImageDecoder::compareEntries(const IconDirectoryEntry& a, const IconDirectoryEntry& b) 158{ 159 // Larger icons are better. After that, higher bit-depth icons are better. 160 const int aEntryArea = a.m_size.width() * a.m_size.height(); 161 const int bEntryArea = b.m_size.width() * b.m_size.height(); 162 return (aEntryArea == bEntryArea) ? (a.m_bitCount > b.m_bitCount) : (aEntryArea > bEntryArea); 163} 164 165void ICOImageDecoder::setDataForPNGDecoderAtIndex(size_t index) 166{ 167 if (!m_pngDecoders[index]) 168 return; 169 170 const IconDirectoryEntry& dirEntry = m_dirEntries[index]; 171 // Copy out PNG data to a separate vector and send to the PNG decoder. 172 // FIXME: Save this copy by making the PNG decoder able to take an 173 // optional offset. 174 RefPtr<SharedBuffer> pngData(SharedBuffer::create(&m_data->data()[dirEntry.m_imageOffset], m_data->size() - dirEntry.m_imageOffset)); 175 m_pngDecoders[index]->setData(pngData.get(), isAllDataReceived()); 176} 177 178void ICOImageDecoder::decode(size_t index, bool onlySize) 179{ 180 if (failed()) 181 return; 182 183 // If we couldn't decode the image but we've received all the data, decoding 184 // has failed. 185 if ((!decodeDirectory() || (!onlySize && !decodeAtIndex(index))) && isAllDataReceived()) 186 setFailed(); 187 // If we're done decoding this frame, we don't need the BMPImageReader or 188 // PNGImageDecoder anymore. (If we failed, these have already been 189 // cleared.) 190 else if ((m_frameBufferCache.size() > index) && (m_frameBufferCache[index].status() == ImageFrame::FrameComplete)) { 191 m_bmpReaders[index].clear(); 192 m_pngDecoders[index].clear(); 193 } 194} 195 196bool ICOImageDecoder::decodeDirectory() 197{ 198 // Read and process directory. 199 if ((m_decodedOffset < sizeOfDirectory) && !processDirectory()) 200 return false; 201 202 // Read and process directory entries. 203 return (m_decodedOffset >= (sizeOfDirectory + (m_dirEntries.size() * sizeOfDirEntry))) || processDirectoryEntries(); 204} 205 206bool ICOImageDecoder::decodeAtIndex(size_t index) 207{ 208 ASSERT_WITH_SECURITY_IMPLICATION(index < m_dirEntries.size()); 209 const IconDirectoryEntry& dirEntry = m_dirEntries[index]; 210 const ImageType imageType = imageTypeAtIndex(index); 211 if (imageType == Unknown) 212 return false; // Not enough data to determine image type yet. 213 214 if (imageType == BMP) { 215 if (!m_bmpReaders[index]) { 216 // We need to have already sized m_frameBufferCache before this, and 217 // we must not resize it again later (see caution in frameCount()). 218 ASSERT(m_frameBufferCache.size() == m_dirEntries.size()); 219 m_bmpReaders[index] = adoptPtr(new BMPImageReader(this, dirEntry.m_imageOffset, 0, true)); 220 m_bmpReaders[index]->setData(m_data.get()); 221 m_bmpReaders[index]->setBuffer(&m_frameBufferCache[index]); 222 } 223 m_frameSize = dirEntry.m_size; 224 bool result = m_bmpReaders[index]->decodeBMP(false); 225 m_frameSize = IntSize(); 226 return result; 227 } 228 229 if (!m_pngDecoders[index]) { 230 m_pngDecoders[index] = adoptPtr( 231 new PNGImageDecoder(m_premultiplyAlpha ? ImageSource::AlphaPremultiplied : ImageSource::AlphaNotPremultiplied, 232 m_ignoreGammaAndColorProfile ? ImageSource::GammaAndColorProfileIgnored : ImageSource::GammaAndColorProfileApplied, m_maxDecodedBytes)); 233 setDataForPNGDecoderAtIndex(index); 234 } 235 // Fail if the size the PNGImageDecoder calculated does not match the size 236 // in the directory. 237 if (m_pngDecoders[index]->isSizeAvailable() && (m_pngDecoders[index]->size() != dirEntry.m_size)) 238 return setFailed(); 239 m_frameBufferCache[index] = *m_pngDecoders[index]->frameBufferAtIndex(0); 240 m_frameBufferCache[index].setPremultiplyAlpha(m_premultiplyAlpha); 241 m_frameBufferCache[index].setRequiredPreviousFrameIndex(kNotFound); 242 return !m_pngDecoders[index]->failed() || setFailed(); 243} 244 245bool ICOImageDecoder::processDirectory() 246{ 247 // Read directory. 248 ASSERT(!m_decodedOffset); 249 if (m_data->size() < sizeOfDirectory) 250 return false; 251 const uint16_t fileType = readUint16(2); 252 const uint16_t idCount = readUint16(4); 253 m_decodedOffset = sizeOfDirectory; 254 255 // See if this is an icon filetype we understand, and make sure we have at 256 // least one entry in the directory. 257 if (((fileType != ICON) && (fileType != CURSOR)) || (!idCount)) 258 return setFailed(); 259 260 m_fileType = static_cast<FileType>(fileType); 261 262 // Enlarge member vectors to hold all the entries. 263 m_dirEntries.resize(idCount); 264 m_bmpReaders.resize(idCount); 265 m_pngDecoders.resize(idCount); 266 return true; 267} 268 269bool ICOImageDecoder::processDirectoryEntries() 270{ 271 // Read directory entries. 272 ASSERT(m_decodedOffset == sizeOfDirectory); 273 if ((m_decodedOffset > m_data->size()) || ((m_data->size() - m_decodedOffset) < (m_dirEntries.size() * sizeOfDirEntry))) 274 return false; 275 for (IconDirectoryEntries::iterator i(m_dirEntries.begin()); i != m_dirEntries.end(); ++i) 276 *i = readDirectoryEntry(); // Updates m_decodedOffset. 277 278 // Make sure the specified image offsets are past the end of the directory 279 // entries. 280 for (IconDirectoryEntries::iterator i(m_dirEntries.begin()); i != m_dirEntries.end(); ++i) { 281 if (i->m_imageOffset < m_decodedOffset) 282 return setFailed(); 283 } 284 285 // Arrange frames in decreasing quality order. 286 std::sort(m_dirEntries.begin(), m_dirEntries.end(), compareEntries); 287 288 // The image size is the size of the largest entry. 289 const IconDirectoryEntry& dirEntry = m_dirEntries.first(); 290 // Technically, this next call shouldn't be able to fail, since the width 291 // and height here are each <= 256, and |m_frameSize| is empty. 292 return setSize(dirEntry.m_size.width(), dirEntry.m_size.height()); 293} 294 295ICOImageDecoder::IconDirectoryEntry ICOImageDecoder::readDirectoryEntry() 296{ 297 // Read icon data. 298 // The casts to uint8_t in the next few lines are because that's the on-disk 299 // type of the width and height values. Storing them in ints (instead of 300 // matching uint8_ts) is so we can record dimensions of size 256 (which is 301 // what a zero byte really means). 302 int width = static_cast<uint8_t>(m_data->data()[m_decodedOffset]); 303 if (!width) 304 width = 256; 305 int height = static_cast<uint8_t>(m_data->data()[m_decodedOffset + 1]); 306 if (!height) 307 height = 256; 308 IconDirectoryEntry entry; 309 entry.m_size = IntSize(width, height); 310 if (m_fileType == CURSOR) { 311 entry.m_bitCount = 0; 312 entry.m_hotSpot = IntPoint(readUint16(4), readUint16(6)); 313 } else { 314 entry.m_bitCount = readUint16(6); 315 entry.m_hotSpot = IntPoint(); 316 } 317 entry.m_imageOffset = readUint32(12); 318 319 // Some icons don't have a bit depth, only a color count. Convert the 320 // color count to the minimum necessary bit depth. It doesn't matter if 321 // this isn't quite what the bitmap info header says later, as we only use 322 // this value to determine which icon entry is best. 323 if (!entry.m_bitCount) { 324 int colorCount = static_cast<uint8_t>(m_data->data()[m_decodedOffset + 2]); 325 if (!colorCount) 326 colorCount = 256; // Vague in the spec, needed by real-world icons. 327 for (--colorCount; colorCount; colorCount >>= 1) 328 ++entry.m_bitCount; 329 } 330 331 m_decodedOffset += sizeOfDirEntry; 332 return entry; 333} 334 335ICOImageDecoder::ImageType ICOImageDecoder::imageTypeAtIndex(size_t index) 336{ 337 // Check if this entry is a BMP or a PNG; we need 4 bytes to check the magic 338 // number. 339 ASSERT_WITH_SECURITY_IMPLICATION(index < m_dirEntries.size()); 340 const uint32_t imageOffset = m_dirEntries[index].m_imageOffset; 341 if ((imageOffset > m_data->size()) || ((m_data->size() - imageOffset) < 4)) 342 return Unknown; 343 return strncmp(&m_data->data()[imageOffset], "\x89PNG", 4) ? BMP : PNG; 344} 345 346} 347