• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2     Copyright (C) 1998 Lars Knoll (knoll@mpi-hd.mpg.de)
3     Copyright (C) 2001 Dirk Mueller <mueller@kde.org>
4     Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
5     Copyright (C) 2009 Torch Mobile Inc. http://www.torchmobile.com/
6 
7     This library is free software; you can redistribute it and/or
8     modify it under the terms of the GNU Library General Public
9     License as published by the Free Software Foundation; either
10     version 2 of the License, or (at your option) any later version.
11 
12     This library is distributed in the hope that it will be useful,
13     but WITHOUT ANY WARRANTY; without even the implied warranty of
14     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15     Library General Public License for more details.
16 
17     You should have received a copy of the GNU Library General Public License
18     along with this library; see the file COPYING.LIB.  If not, write to
19     the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
20     Boston, MA 02110-1301, USA.
21 
22     This class provides all functionality needed for loading images, style sheets and html
23     pages from the web. It has a memory cache for these objects.
24 */
25 
26 #ifndef ResourceFetcher_h
27 #define ResourceFetcher_h
28 
29 #include "core/fetch/CachePolicy.h"
30 #include "core/fetch/FetchInitiatorInfo.h"
31 #include "core/fetch/FetchRequest.h"
32 #include "core/fetch/Resource.h"
33 #include "core/fetch/ResourceLoaderHost.h"
34 #include "core/fetch/ResourceLoaderOptions.h"
35 #include "core/fetch/ResourcePtr.h"
36 #include "platform/Timer.h"
37 #include "wtf/Deque.h"
38 #include "wtf/HashMap.h"
39 #include "wtf/HashSet.h"
40 #include "wtf/ListHashSet.h"
41 #include "wtf/text/StringHash.h"
42 
43 namespace blink {
44 
45 class CSSStyleSheetResource;
46 class DocumentResource;
47 class FetchContext;
48 class FontResource;
49 class ImageResource;
50 class RawResource;
51 class ScriptResource;
52 class SubstituteData;
53 class XSLStyleSheetResource;
54 class Document;
55 class DocumentLoader;
56 class LocalFrame;
57 class FrameLoader;
58 class ImageLoader;
59 class KURL;
60 class ResourceTimingInfo;
61 class ResourceLoaderSet;
62 
63 // The ResourceFetcher provides a per-context interface to the MemoryCache
64 // and enforces a bunch of security checks and rules for resource revalidation.
65 // Its lifetime is roughly per-DocumentLoader, in that it is generally created
66 // in the DocumentLoader constructor and loses its ability to generate network
67 // requests when the DocumentLoader is destroyed. Documents also hold a
68 // RefPtr<ResourceFetcher> for their lifetime (and will create one if they
69 // are initialized without a LocalFrame), so a Document can keep a ResourceFetcher
70 // alive past detach if scripts still reference the Document.
71 class ResourceFetcher FINAL : public RefCountedWillBeGarbageCollectedFinalized<ResourceFetcher>, public ResourceLoaderHost {
72     WTF_MAKE_NONCOPYABLE(ResourceFetcher); WTF_MAKE_FAST_ALLOCATED_WILL_BE_REMOVED;
73     WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(ResourceFetcher);
74 friend class ImageLoader;
75 friend class ResourceCacheValidationSuppressor;
76 
77 public:
create(DocumentLoader * documentLoader)78     static PassRefPtrWillBeRawPtr<ResourceFetcher> create(DocumentLoader* documentLoader) { return adoptRefWillBeNoop(new ResourceFetcher(documentLoader)); }
79     virtual ~ResourceFetcher();
80     virtual void trace(Visitor*);
81 
82 #if !ENABLE(OILPAN)
83     using RefCounted<ResourceFetcher>::ref;
84     using RefCounted<ResourceFetcher>::deref;
85 #endif
86 
87     ResourcePtr<Resource> fetchSynchronously(FetchRequest&);
88     ResourcePtr<ImageResource> fetchImage(FetchRequest&);
89     ResourcePtr<CSSStyleSheetResource> fetchCSSStyleSheet(FetchRequest&);
90     ResourcePtr<ScriptResource> fetchScript(FetchRequest&);
91     ResourcePtr<FontResource> fetchFont(FetchRequest&);
92     ResourcePtr<RawResource> fetchRawResource(FetchRequest&);
93     ResourcePtr<RawResource> fetchMainResource(FetchRequest&, const SubstituteData&);
94     ResourcePtr<DocumentResource> fetchSVGDocument(FetchRequest&);
95     ResourcePtr<XSLStyleSheetResource> fetchXSLStyleSheet(FetchRequest&);
96     ResourcePtr<Resource> fetchLinkResource(Resource::Type, FetchRequest&);
97     ResourcePtr<RawResource> fetchImport(FetchRequest&);
98     ResourcePtr<RawResource> fetchMedia(FetchRequest&);
99     ResourcePtr<RawResource> fetchTextTrack(FetchRequest&);
100 
101     // Logs an access denied message to the console for the specified URL.
102     void printAccessDeniedMessage(const KURL&) const;
103 
104     Resource* cachedResource(const KURL&) const;
105 
106     typedef HashMap<String, ResourcePtr<Resource> > DocumentResourceMap;
allResources()107     const DocumentResourceMap& allResources() const { return m_documentResources; }
108 
autoLoadImages()109     bool autoLoadImages() const { return m_autoLoadImages; }
110     void setAutoLoadImages(bool);
111 
112     void setImagesEnabled(bool);
113 
114     bool shouldDeferImageLoad(const KURL&) const;
115 
116     LocalFrame* frame() const; // Can be null
117     FetchContext& context() const;
document()118     Document* document() const { return m_document; } // Can be null
setDocument(RawPtr<Document> document)119     void setDocument(RawPtr<Document> document) { m_document = document; }
120 
documentLoader()121     DocumentLoader* documentLoader() const { return m_documentLoader; }
clearDocumentLoader()122     void clearDocumentLoader() { m_documentLoader = 0; }
123 
124     void garbageCollectDocumentResources();
125 
requestCount()126     int requestCount() const { return m_requestCount; }
127 
128     bool isPreloaded(const String& urlString) const;
129     void clearPreloads();
130     void preload(Resource::Type, FetchRequest&, const String& charset);
131     void printPreloadStats();
132 
133     void setDefersLoading(bool);
134     void stopFetching();
135     bool isFetching() const;
136 
137     // ResourceLoaderHost
138     virtual void incrementRequestCount(const Resource*) OVERRIDE;
139     virtual void decrementRequestCount(const Resource*) OVERRIDE;
140     virtual void didLoadResource(Resource*) OVERRIDE;
141     virtual void redirectReceived(Resource*, const ResourceResponse&) OVERRIDE;
142     virtual void didFinishLoading(const Resource*, double finishTime, int64_t encodedDataLength) OVERRIDE;
143     virtual void didChangeLoadingPriority(const Resource*, ResourceLoadPriority, int intraPriorityValue) OVERRIDE;
144     virtual void didFailLoading(const Resource*, const ResourceError&) OVERRIDE;
145     virtual void willSendRequest(unsigned long identifier, ResourceRequest&, const ResourceResponse& redirectResponse, const FetchInitiatorInfo&) OVERRIDE;
146     virtual void didReceiveResponse(const Resource*, const ResourceResponse&) OVERRIDE;
147     virtual void didReceiveData(const Resource*, const char* data, int dataLength, int encodedDataLength) OVERRIDE;
148     virtual void didDownloadData(const Resource*, int dataLength, int encodedDataLength) OVERRIDE;
149     virtual void subresourceLoaderFinishedLoadingOnePart(ResourceLoader*) OVERRIDE;
150     virtual void didInitializeResourceLoader(ResourceLoader*) OVERRIDE;
151     virtual void willTerminateResourceLoader(ResourceLoader*) OVERRIDE;
152     virtual void willStartLoadingResource(Resource*, ResourceRequest&) OVERRIDE;
153     virtual bool defersLoading() const OVERRIDE;
154     virtual bool isLoadedBy(ResourceLoaderHost*) const OVERRIDE;
155     virtual bool canAccessRedirect(Resource*, ResourceRequest&, const ResourceResponse&, ResourceLoaderOptions&) OVERRIDE;
156     virtual bool canAccessResource(Resource*, SecurityOrigin*, const KURL&) const OVERRIDE;
157 
158 #if !ENABLE(OILPAN)
159     virtual void refResourceLoaderHost() OVERRIDE;
160     virtual void derefResourceLoaderHost() OVERRIDE;
161 #endif
162 
163     enum ResourceLoadStartType {
164         ResourceLoadingFromNetwork,
165         ResourceLoadingFromCache
166     };
167     void requestLoadStarted(Resource*, const FetchRequest&, ResourceLoadStartType);
168     static const ResourceLoaderOptions& defaultResourceOptions();
169 private:
170 
171     explicit ResourceFetcher(DocumentLoader*);
172 
173     bool shouldLoadNewResource(Resource::Type) const;
174 
175     ResourcePtr<Resource> requestResource(Resource::Type, FetchRequest&);
176     ResourcePtr<Resource> createResourceForRevalidation(const FetchRequest&, Resource*);
177     ResourcePtr<Resource> createResourceForLoading(Resource::Type, FetchRequest&, const String& charset);
178     void preCacheDataURIImage(const FetchRequest&);
179     void preCacheSubstituteDataForMainResource(const FetchRequest&, const SubstituteData&);
180     void storeResourceTimingInitiatorInformation(Resource*);
181     void requestPreload(Resource::Type, FetchRequest&, const String& charset);
182 
183     enum RevalidationPolicy { Use, Revalidate, Reload, Load };
184     RevalidationPolicy determineRevalidationPolicy(Resource::Type, const FetchRequest&, Resource* existingResource) const;
185 
186     void determineRequestContext(ResourceRequest&, Resource::Type);
187     ResourceRequestCachePolicy resourceRequestCachePolicy(const ResourceRequest&, Resource::Type);
188     void addAdditionalRequestHeaders(ResourceRequest&, Resource::Type);
189 
190     bool canRequest(Resource::Type, const ResourceRequest&, const KURL&, const ResourceLoaderOptions&, bool forPreload, FetchRequest::OriginRestriction) const;
191 
192     static bool resourceNeedsLoad(Resource*, const FetchRequest&, RevalidationPolicy);
193 
194     void notifyLoadedFromMemoryCache(Resource*);
195 
196     void garbageCollectDocumentResourcesTimerFired(Timer<ResourceFetcher>*);
197     void scheduleDocumentResourcesGC();
198 
199     void resourceTimingReportTimerFired(Timer<ResourceFetcher>*);
200 
201     bool clientDefersImage(const KURL&) const;
202     void reloadImagesIfNotDeferred();
203 
204     HashSet<String> m_validatedURLs;
205     mutable DocumentResourceMap m_documentResources;
206     // FIXME: Oilpan: Ideally this should just be a traced Member but that will
207     // currently leak because RenderStyle and its data are not on the heap.
208     // See crbug.com/383860 for details.
209     RawPtrWillBeWeakMember<Document> m_document;
210     DocumentLoader* m_documentLoader;
211 
212     int m_requestCount;
213 
214     OwnPtr<ListHashSet<Resource*> > m_preloads;
215 
216     Timer<ResourceFetcher> m_garbageCollectDocumentResourcesTimer;
217     Timer<ResourceFetcher> m_resourceTimingReportTimer;
218 
219     typedef HashMap<Resource*, RefPtr<ResourceTimingInfo> > ResourceTimingInfoMap;
220     ResourceTimingInfoMap m_resourceTimingInfoMap;
221 
222     HashMap<RefPtr<ResourceTimingInfo>, bool> m_scheduledResourceTimingReports;
223 
224     OwnPtrWillBeMember<ResourceLoaderSet> m_loaders;
225     OwnPtrWillBeMember<ResourceLoaderSet> m_multipartLoaders;
226 
227     // Used in hit rate histograms.
228     class DeadResourceStatsRecorder {
229     public:
230         DeadResourceStatsRecorder();
231         ~DeadResourceStatsRecorder();
232 
233         void update(RevalidationPolicy);
234 
235     private:
236         int m_useCount;
237         int m_revalidateCount;
238         int m_loadCount;
239     };
240     DeadResourceStatsRecorder m_deadStatsRecorder;
241 
242     // 29 bits left
243     bool m_autoLoadImages : 1;
244     bool m_imagesEnabled : 1;
245     bool m_allowStaleResources : 1;
246 };
247 
248 class ResourceCacheValidationSuppressor {
249     WTF_MAKE_NONCOPYABLE(ResourceCacheValidationSuppressor);
250     WTF_MAKE_FAST_ALLOCATED;
251 public:
ResourceCacheValidationSuppressor(ResourceFetcher * loader)252     ResourceCacheValidationSuppressor(ResourceFetcher* loader)
253         : m_loader(loader)
254         , m_previousState(false)
255     {
256         if (m_loader) {
257             m_previousState = m_loader->m_allowStaleResources;
258             m_loader->m_allowStaleResources = true;
259         }
260     }
~ResourceCacheValidationSuppressor()261     ~ResourceCacheValidationSuppressor()
262     {
263         if (m_loader)
264             m_loader->m_allowStaleResources = m_previousState;
265     }
266 private:
267     ResourceFetcher* m_loader;
268     bool m_previousState;
269 };
270 
271 } // namespace blink
272 
273 #endif
274