WebKitTools/DumpRenderTree/cg/PixelDumpSupportCG.cpp

/*
 * Copyright (C) 2005, 2006, 2007 Apple Inc. All rights reserved.
 *           (C) 2007 Graham Dennis (graham.dennis@gmail.com)
 *           (C) 2007 Eric Seidel <eric@webkit.org>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1.  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 * 2.  Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
 *     its contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "config.h"
#include "PixelDumpSupportCG.h"

#include "DumpRenderTree.h"
#include "LayoutTestController.h"
#include <ImageIO/CGImageDestination.h>
#include <algorithm>
#include <ctype.h>
#include <wtf/Assertions.h>
#include <wtf/RefPtr.h>
#include <wtf/RetainPtr.h>
#include <wtf/StringExtras.h>

#if PLATFORM(WIN)
#include "MD5.h"
#elif PLATFORM(MAC)
#include <LaunchServices/UTCoreTypes.h>
#define COMMON_DIGEST_FOR_OPENSSL
#include <CommonCrypto/CommonDigest.h>
#endif

#if PLATFORM(WIN)
static const CFStringRef kUTTypePNG = CFSTR("public.png");
#endif

static void printPNG(CGImageRef image)
{
    RetainPtr<CFMutableDataRef> imageData(AdoptCF, CFDataCreateMutable(0, 0));
    RetainPtr<CGImageDestinationRef> imageDest(AdoptCF, CGImageDestinationCreateWithData(imageData.get(), kUTTypePNG, 1, 0));
    CGImageDestinationAddImage(imageDest.get(), image, 0);
    CGImageDestinationFinalize(imageDest.get());

    printf("Content-Type: %s\n", "image/png");
    printf("Content-Length: %lu\n", CFDataGetLength(imageData.get()));

    fwrite(CFDataGetBytePtr(imageData.get()), 1, CFDataGetLength(imageData.get()), stdout);
}

static void computeMD5HashStringForBitmapContext(CGContextRef bitmapContext, char hashString[33])
{
    ASSERT(CGBitmapContextGetBitsPerPixel(bitmapContext) == 32); // ImageDiff assumes 32 bit RGBA, we must as well.
    size_t pixelsHigh = CGBitmapContextGetHeight(bitmapContext);
    size_t pixelsWide = CGBitmapContextGetWidth(bitmapContext);
    size_t bytesPerRow = CGBitmapContextGetBytesPerRow(bitmapContext);

    // We need to swap the bytes to ensure consistent hashes independently of endianness
    MD5_CTX md5Context;
    MD5_Init(&md5Context);
    unsigned char* bitmapData = static_cast<unsigned char*>(CGBitmapContextGetData(bitmapContext));
#if PLATFORM(MAC)
    if ((CGBitmapContextGetBitmapInfo(bitmapContext) & kCGBitmapByteOrderMask) == kCGBitmapByteOrder32Big) {
        for (unsigned row = 0; row < pixelsHigh; row++) {
            uint32_t buffer[pixelsWide];
            for (unsigned column = 0; column < pixelsWide; column++)
                buffer[column] = OSReadLittleInt32(bitmapData, 4 * column);
            MD5_Update(&md5Context, buffer, 4 * pixelsWide);
            bitmapData += bytesPerRow;
        }
    } else
#endif
    {
        for (unsigned row = 0; row < pixelsHigh; row++) {
            MD5_Update(&md5Context, bitmapData, 4 * pixelsWide);
            bitmapData += bytesPerRow;
        }
    }
    unsigned char hash[16];
    MD5_Final(hash, &md5Context);

    hashString[0] = '\0';
    for (int i = 0; i < 16; i++)
        snprintf(hashString, 33, "%s%02x", hashString, hash[i]);
}

void dumpWebViewAsPixelsAndCompareWithExpected(const std::string& expectedHash)
{
    RefPtr<BitmapContext> context;
    
#if PLATFORM(MAC)
    context = createBitmapContextFromWebView(gLayoutTestController->testOnscreen(), gLayoutTestController->testRepaint(), gLayoutTestController->testRepaintSweepHorizontally(), gLayoutTestController->dumpSelectionRect());
#endif
    ASSERT(context);
    
    // Compute the hash of the bitmap context pixels
    char actualHash[33];
    computeMD5HashStringForBitmapContext(context->cgContext(), actualHash);
    printf("\nActualHash: %s\n", actualHash);
    
    // Check the computed hash against the expected one and dump image on mismatch
    bool dumpImage = true;
    if (expectedHash.length() > 0) {
        ASSERT(expectedHash.length() == 32);
        
        printf("\nExpectedHash: %s\n", expectedHash.c_str());
        
        if (expectedHash == actualHash)     // FIXME: do case insensitive compare
            dumpImage = false;
    }
    
    if (dumpImage) {
        RetainPtr<CGImageRef> image(AdoptCF, CGBitmapContextCreateImage(context->cgContext()));
        printPNG(image.get());
    }
}