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      1 /*
      2  * Copyright (C) 2005, 2006, 2007 Apple Inc. All rights reserved.
      3  *           (C) 2007 Graham Dennis (graham.dennis (at) gmail.com)
      4  *           (C) 2007 Eric Seidel <eric (at) webkit.org>
      5  *
      6  * Redistribution and use in source and binary forms, with or without
      7  * modification, are permitted provided that the following conditions
      8  * are met:
      9  *
     10  * 1.  Redistributions of source code must retain the above copyright
     11  *     notice, this list of conditions and the following disclaimer.
     12  * 2.  Redistributions in binary form must reproduce the above copyright
     13  *     notice, this list of conditions and the following disclaimer in the
     14  *     documentation and/or other materials provided with the distribution.
     15  * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
     16  *     its contributors may be used to endorse or promote products derived
     17  *     from this software without specific prior written permission.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
     20  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
     21  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
     22  * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
     23  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
     24  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
     25  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
     26  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     28  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     29  */
     30 
     31 #include "config.h"
     32 #include "PixelDumpSupportCG.h"
     33 
     34 #include "DumpRenderTree.h"
     35 #include "PixelDumpSupport.h"
     36 #include <ImageIO/CGImageDestination.h>
     37 #include <algorithm>
     38 #include <ctype.h>
     39 #include <wtf/Assertions.h>
     40 #include <wtf/RefPtr.h>
     41 #include <wtf/RetainPtr.h>
     42 #include <wtf/StringExtras.h>
     43 
     44 #if PLATFORM(WIN)
     45 #include "MD5.h"
     46 #elif PLATFORM(MAC)
     47 #include <LaunchServices/UTCoreTypes.h>
     48 #define COMMON_DIGEST_FOR_OPENSSL
     49 #include <CommonCrypto/CommonDigest.h>
     50 #endif
     51 
     52 using namespace std;
     53 
     54 #if PLATFORM(WIN)
     55 static const CFStringRef kUTTypePNG = CFSTR("public.png");
     56 #endif
     57 
     58 static void printPNG(CGImageRef image, const char* checksum)
     59 {
     60     RetainPtr<CFMutableDataRef> imageData(AdoptCF, CFDataCreateMutable(0, 0));
     61     RetainPtr<CGImageDestinationRef> imageDest(AdoptCF, CGImageDestinationCreateWithData(imageData.get(), kUTTypePNG, 1, 0));
     62     CGImageDestinationAddImage(imageDest.get(), image, 0);
     63     CGImageDestinationFinalize(imageDest.get());
     64 
     65     const UInt8* data = CFDataGetBytePtr(imageData.get());
     66     CFIndex dataLength = CFDataGetLength(imageData.get());
     67 
     68     printPNG(static_cast<const unsigned char*>(data), static_cast<size_t>(dataLength), checksum);
     69 }
     70 
     71 void computeMD5HashStringForBitmapContext(BitmapContext* context, char hashString[33])
     72 {
     73     CGContextRef bitmapContext = context->cgContext();
     74 
     75     ASSERT(CGBitmapContextGetBitsPerPixel(bitmapContext) == 32); // ImageDiff assumes 32 bit RGBA, we must as well.
     76     size_t pixelsHigh = CGBitmapContextGetHeight(bitmapContext);
     77     size_t pixelsWide = CGBitmapContextGetWidth(bitmapContext);
     78     size_t bytesPerRow = CGBitmapContextGetBytesPerRow(bitmapContext);
     79 
     80     // We need to swap the bytes to ensure consistent hashes independently of endianness
     81     MD5_CTX md5Context;
     82     MD5_Init(&md5Context);
     83     unsigned char* bitmapData = static_cast<unsigned char*>(CGBitmapContextGetData(bitmapContext));
     84 #if PLATFORM(MAC)
     85     if ((CGBitmapContextGetBitmapInfo(bitmapContext) & kCGBitmapByteOrderMask) == kCGBitmapByteOrder32Big) {
     86         for (unsigned row = 0; row < pixelsHigh; row++) {
     87             uint32_t buffer[pixelsWide];
     88             for (unsigned column = 0; column < pixelsWide; column++)
     89                 buffer[column] = OSReadLittleInt32(bitmapData, 4 * column);
     90             MD5_Update(&md5Context, buffer, 4 * pixelsWide);
     91             bitmapData += bytesPerRow;
     92         }
     93     } else
     94 #endif
     95     {
     96         for (unsigned row = 0; row < pixelsHigh; row++) {
     97             MD5_Update(&md5Context, bitmapData, 4 * pixelsWide);
     98             bitmapData += bytesPerRow;
     99         }
    100     }
    101     unsigned char hash[16];
    102     MD5_Final(hash, &md5Context);
    103 
    104     hashString[0] = '\0';
    105     for (int i = 0; i < 16; i++)
    106         snprintf(hashString, 33, "%s%02x", hashString, hash[i]);
    107 }
    108 
    109 void dumpBitmap(BitmapContext* context, const char* checksum)
    110 {
    111     RetainPtr<CGImageRef> image(AdoptCF, CGBitmapContextCreateImage(context->cgContext()));
    112     printPNG(image.get(), checksum);
    113 }
    114