third_party/WebKit/Source/core/css/CSSImageSetValue.cpp

   1 /*
   2  * Copyright (C) 2012 Apple 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
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
  14  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  15  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  16  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
  17  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  18  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  19  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  20  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  21  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  22  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
  23  * THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #include "config.h"
  27 #include "core/css/CSSImageSetValue.h"
  28
  29 #include "core/css/CSSImageValue.h"
  30 #include "core/css/CSSPrimitiveValue.h"
  31 #include "core/dom/Document.h"
  32 #include "core/fetch/FetchInitiatorTypeNames.h"
  33 #include "core/fetch/FetchRequest.h"
  34 #include "core/fetch/ImageResource.h"
  35 #include "core/fetch/ResourceFetcher.h"
  36 #include "core/fetch/ResourceLoaderOptions.h"
  37 #include "core/style/StyleFetchedImageSet.h"
  38 #include "core/style/StylePendingImage.h"
  39 #include "platform/weborigin/KURL.h"
  40 #include "platform/weborigin/SecurityPolicy.h"
  41 #include "wtf/text/StringBuilder.h"
  42
  43 namespace blink {
  44
  45 CSSImageSetValue::CSSImageSetValue()
  46     : CSSValueList(ImageSetClass, CommaSeparator)
  47     , m_accessedBestFitImage(false)
  48     , m_scaleFactor(1)
  49 {
  50 }
  51
  52 CSSImageSetValue::~CSSImageSetValue()
  53 {
  54 #if !ENABLE(OILPAN)
  55     if (m_imageSet && m_imageSet->isImageResourceSet())
  56         toStyleFetchedImageSet(m_imageSet)->clearImageSetValue();
  57 #endif
  58 }
  59
  60 void CSSImageSetValue::fillImageSet()
  61 {
  62     size_t length = this->length();
  63     size_t i = 0;
  64     while (i < length) {
  65         CSSImageValue* imageValue = toCSSImageValue(item(i));
  66         String imageURL = imageValue->url();
  67
  68         ++i;
  69         ASSERT_WITH_SECURITY_IMPLICATION(i < length);
  70         CSSValue* scaleFactorValue = item(i);
  71         float scaleFactor = toCSSPrimitiveValue(scaleFactorValue)->getFloatValue();
  72
  73         ImageWithScale image;
  74         image.imageURL = imageURL;
  75         image.referrer = SecurityPolicy::generateReferrer(imageValue->referrer().referrerPolicy, KURL(ParsedURLString, imageURL), imageValue->referrer().referrer);
  76         image.scaleFactor = scaleFactor;
  77         m_imagesInSet.append(image);
  78         ++i;
  79     }
  80
  81     // Sort the images so that they are stored in order from lowest resolution to highest.
  82     std::sort(m_imagesInSet.begin(), m_imagesInSet.end(), CSSImageSetValue::compareByScaleFactor);
  83 }
  84
  85 CSSImageSetValue::ImageWithScale CSSImageSetValue::bestImageForScaleFactor()
  86 {
  87     ImageWithScale image;
  88     size_t numberOfImages = m_imagesInSet.size();
  89     for (size_t i = 0; i < numberOfImages; ++i) {
  90         image = m_imagesInSet.at(i);
  91         if (image.scaleFactor >= m_scaleFactor)
  92             return image;
  93     }
  94     return image;
  95 }
  96
  97 StyleFetchedImageSet* CSSImageSetValue::cachedImageSet(Document* document, float deviceScaleFactor, const ResourceLoaderOptions& options)
  98 {
  99     ASSERT(document);
 100
 101     m_scaleFactor = deviceScaleFactor;
 102
 103     if (!m_imagesInSet.size())
 104         fillImageSet();
 105
 106     if (!m_accessedBestFitImage) {
 107         // FIXME: In the future, we want to take much more than deviceScaleFactor into acount here.
 108         // All forms of scale should be included: Page::pageScaleFactor(), LocalFrame::pageZoomFactor(),
 109         // and any CSS transforms. https://bugs.webkit.org/show_bug.cgi?id=81698
 110         ImageWithScale image = bestImageForScaleFactor();
 111         FetchRequest request(ResourceRequest(document->completeURL(image.imageURL)), FetchInitiatorTypeNames::css, options);
 112         request.mutableResourceRequest().setHTTPReferrer(image.referrer);
 113
 114         if (options.corsEnabled == IsCORSEnabled)
 115             request.setCrossOriginAccessControl(document->securityOrigin(), options.allowCredentials, options.credentialsRequested);
 116
 117         if (ResourcePtr<ImageResource> cachedImage = ImageResource::fetch(request, document->fetcher())) {
 118             m_imageSet = StyleFetchedImageSet::create(cachedImage.get(), image.scaleFactor, this);
 119             m_accessedBestFitImage = true;
 120         }
 121     }
 122
 123     return (m_imageSet && m_imageSet->isImageResourceSet()) ? toStyleFetchedImageSet(m_imageSet) : nullptr;
 124 }
 125
 126 StyleFetchedImageSet* CSSImageSetValue::cachedImageSet(Document* document, float deviceScaleFactor)
 127 {
 128     return cachedImageSet(document, deviceScaleFactor, ResourceFetcher::defaultResourceOptions());
 129 }
 130
 131 StyleImage* CSSImageSetValue::cachedOrPendingImageSet(float deviceScaleFactor)
 132 {
 133     if (!m_imageSet) {
 134         m_imageSet = StylePendingImage::create(this);
 135     } else if (!m_imageSet->isPendingImage()) {
 136         // If the deviceScaleFactor has changed, we may not have the best image loaded, so we have to re-assess.
 137         if (deviceScaleFactor != m_scaleFactor) {
 138             m_accessedBestFitImage = false;
 139             m_imageSet = StylePendingImage::create(this);
 140         }
 141     }
 142
 143     return m_imageSet.get();
 144 }
 145
 146 String CSSImageSetValue::customCSSText() const
 147 {
 148     StringBuilder result;
 149     result.append("-webkit-image-set(");
 150
 151     size_t length = this->length();
 152     size_t i = 0;
 153     while (i < length) {
 154         if (i > 0)
 155             result.appendLiteral(", ");
 156
 157         const CSSValue* imageValue = item(i);
 158         result.append(imageValue->cssText());
 159         result.append(' ');
 160
 161         ++i;
 162         ASSERT_WITH_SECURITY_IMPLICATION(i < length);
 163         const CSSValue* scaleFactorValue = item(i);
 164         result.append(scaleFactorValue->cssText());
 165         // FIXME: Eventually the scale factor should contain it's own unit http://wkb.ug/100120.
 166         // For now 'x' is hard-coded in the parser, so we hard-code it here too.
 167         result.append('x');
 168
 169         ++i;
 170     }
 171
 172     result.append(')');
 173     return result.toString();
 174 }
 175
 176 bool CSSImageSetValue::hasFailedOrCanceledSubresources() const
 177 {
 178     if (!m_imageSet || !m_imageSet->isImageResourceSet())
 179         return false;
 180     if (Resource* cachedResource = toStyleFetchedImageSet(m_imageSet)->cachedImage())
 181         return cachedResource->loadFailedOrCanceled();
 182     return true;
 183 }
 184
 185 DEFINE_TRACE_AFTER_DISPATCH(CSSImageSetValue)
 186 {
 187     visitor->trace(m_imageSet);
 188     CSSValueList::traceAfterDispatch(visitor);
 189 }
 190
 191 PassRefPtrWillBeRawPtr<CSSImageSetValue> CSSImageSetValue::valueWithURLsMadeAbsolute()
 192 {
 193     CSSImageSetValue* value = CSSImageSetValue::create().get();
 194     for (auto& item : *this)
 195         item->isImageValue() ? value->append(toCSSImageValue(*item).valueWithURLMadeAbsolute()) : value->append(item);
 196     return adoptRefWillBeNoop(value);
 197 }
 198
 199
 200 } // namespace blink