2 Copyright (C) 1998 Lars Knoll (knoll@mpi-hd.mpg.de)
3 Copyright (C) 2001 Dirk Mueller <mueller@kde.org>
4 Copyright (C) 2006 Samuel Weinig (sam.weinig@gmail.com)
5 Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
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.
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.
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.
26 #include "core/fetch/ResourceLoaderOptions.h"
27 #include "platform/Timer.h"
28 #include "platform/network/ResourceError.h"
29 #include "platform/network/ResourceLoadPriority.h"
30 #include "platform/network/ResourceRequest.h"
31 #include "platform/network/ResourceResponse.h"
32 #include "wtf/HashCountedSet.h"
33 #include "wtf/HashSet.h"
34 #include "wtf/OwnPtr.h"
35 #include "wtf/text/WTFString.h"
39 struct FetchInitiatorInfo;
43 class ResourcePtrBase;
44 class ResourceFetcher;
45 class InspectorResource;
46 class PurgeableBuffer;
51 // A resource that is held in the cache. Classes who want to use this object should derive
52 // from ResourceClient, to get the function calls in case the requested data has arrived.
53 // This class also does the actual communication with the loader to obtain the resource from the network.
55 WTF_MAKE_NONCOPYABLE(Resource); WTF_MAKE_FAST_ALLOCATED;
56 friend class MemoryCache;
57 friend class InspectorResource;
77 Unknown, // let cache decide what to do with it
78 Pending, // only partially loaded
79 Cached, // regular case
84 Resource(const ResourceRequest&, Type);
87 // Determines the order in which CachedResources are evicted
88 // from the decoded resources cache.
89 enum CacheLiveResourcePriority {
90 CacheLiveResourcePriorityLow = 0,
91 CacheLiveResourcePriorityHigh
94 virtual void load(ResourceFetcher*, const ResourceLoaderOptions&);
96 virtual void setEncoding(const String&) { }
97 virtual String encoding() const { return String(); }
98 virtual void appendData(const char*, int);
99 virtual void error(Resource::Status);
101 void setNeedsSynchronousCacheHit(bool needsSynchronousCacheHit) { m_needsSynchronousCacheHit = needsSynchronousCacheHit; }
103 void setResourceError(const ResourceError& error) { m_error = error; }
104 const ResourceError& resourceError() const { return m_error; }
106 void setIdentifier(unsigned long identifier) { m_identifier = identifier; }
107 unsigned long identifier() const { return m_identifier; }
109 virtual bool shouldIgnoreHTTPStatusCodeErrors() const { return false; }
111 ResourceRequest& resourceRequest() { return m_resourceRequest; }
112 const KURL& url() const { return m_resourceRequest.url();}
113 Type type() const { return static_cast<Type>(m_type); }
114 const ResourceLoaderOptions& options() const { return m_options; }
115 void setOptions(const ResourceLoaderOptions& options) { m_options = options; }
117 void didChangePriority(ResourceLoadPriority);
119 void addClient(ResourceClient*);
120 void removeClient(ResourceClient*);
121 bool hasClients() const { return !m_clients.isEmpty() || !m_clientsAwaitingCallback.isEmpty(); }
122 bool deleteIfPossible();
125 PreloadNotReferenced,
127 PreloadReferencedWhileLoading,
128 PreloadReferencedWhileComplete
130 PreloadResult preloadResult() const { return static_cast<PreloadResult>(m_preloadResult); }
132 virtual void didAddClient(ResourceClient*);
133 virtual void didRemoveClient(ResourceClient*) { }
134 virtual void allClientsRemoved();
136 unsigned count() const { return m_clients.size(); }
138 Status status() const { return static_cast<Status>(m_status); }
139 void setStatus(Status status) { m_status = status; }
141 size_t size() const { return encodedSize() + decodedSize() + overheadSize(); }
142 size_t encodedSize() const { return m_encodedSize; }
143 size_t decodedSize() const { return m_decodedSize; }
144 size_t overheadSize() const;
146 bool isLoaded() const { return !m_loading; } // FIXME. Method name is inaccurate. Loading might not have started yet.
148 bool isLoading() const { return m_loading; }
149 void setLoading(bool b) { m_loading = b; }
150 virtual bool stillNeedsLoad() const { return false; }
152 ResourceLoader* loader() const { return m_loader.get(); }
154 virtual bool isImage() const { return false; }
155 bool ignoreForRequestCount() const
157 return type() == MainResource
158 || type() == LinkPrefetch
159 || type() == LinkSubresource
163 void updateForAccess();
164 unsigned accessCount() const { return m_accessCount; }
166 // Computes the status of an object after loading.
167 // Updates the expire date on the cache entry file
168 void finish(double finishTime = 0.0);
170 // FIXME: Remove the stringless variant once all the callsites' error messages are updated.
171 bool passesAccessControlCheck(SecurityOrigin*);
172 bool passesAccessControlCheck(SecurityOrigin*, String& errorDescription);
174 // Called by the cache if the object has been removed from the cache
175 // while still being referenced. This means the object should delete itself
176 // if the number of clients observing it ever drops to 0.
177 // The resource can be brought back to cache after successful revalidation.
178 void setInCache(bool inCache) { m_inCache = inCache; }
179 bool inCache() const { return m_inCache; }
181 void setCacheLiveResourcePriority(CacheLiveResourcePriority);
182 unsigned cacheLiveResourcePriority() const { return m_cacheLiveResourcePriority; }
183 bool inLiveDecodedResourcesList() { return m_inLiveDecodedResourcesList; }
187 SharedBuffer* resourceBuffer() const { ASSERT(!m_purgeableData); return m_data.get(); }
188 void setResourceBuffer(PassRefPtr<SharedBuffer>);
190 virtual void willSendRequest(ResourceRequest&, const ResourceResponse&);
192 virtual void updateRequest(const ResourceRequest&) { }
193 virtual void responseReceived(const ResourceResponse&);
194 void setResponse(const ResourceResponse& response) { m_response = response; }
195 const ResourceResponse& response() const { return m_response; }
197 // Sets the serialized metadata retrieved from the platform's cache.
198 void setSerializedCachedMetadata(const char*, size_t);
200 // Caches the given metadata in association with this resource and suggests
201 // that the platform persist it. The dataTypeID is a pseudo-randomly chosen
202 // identifier that is used to distinguish data generated by the caller.
203 void setCachedMetadata(unsigned dataTypeID, const char*, size_t);
205 // Returns cached metadata of the given type associated with this resource.
206 CachedMetadata* cachedMetadata(unsigned dataTypeID) const;
208 bool canDelete() const { return !hasClients() && !m_loader && !m_preloadCount && !m_handleCount && !m_protectorCount && !m_resourceToRevalidate && !m_proxyResource; }
209 bool hasOneHandle() const { return m_handleCount == 1; }
211 // List of acceptable MIME types separated by ",".
212 // A MIME type may contain a wildcard, e.g. "text/*".
213 AtomicString accept() const { return m_accept; }
214 void setAccept(const AtomicString& accept) { m_accept = accept; }
216 bool wasCanceled() const { return m_error.isCancellation(); }
217 bool errorOccurred() const { return m_status == LoadError || m_status == DecodeError; }
218 bool loadFailedOrCanceled() { return !m_error.isNull(); }
220 DataBufferingPolicy dataBufferingPolicy() const { return m_options.dataBufferingPolicy; }
221 void setDataBufferingPolicy(DataBufferingPolicy);
223 bool isPreloaded() const { return m_preloadCount; }
224 void increasePreloadCount() { ++m_preloadCount; }
225 void decreasePreloadCount() { ASSERT(m_preloadCount); --m_preloadCount; }
227 void registerHandle(ResourcePtrBase* h);
228 void unregisterHandle(ResourcePtrBase* h);
230 bool canReuseRedirectChain() const;
231 bool mustRevalidateDueToCacheHeaders() const;
232 bool canUseCacheValidator() const;
233 bool isCacheValidator() const { return m_resourceToRevalidate; }
234 Resource* resourceToRevalidate() const { return m_resourceToRevalidate; }
235 void setResourceToRevalidate(Resource*);
237 bool isPurgeable() const;
238 bool wasPurged() const;
241 virtual void didSendData(unsigned long long /* bytesSent */, unsigned long long /* totalBytesToBeSent */) { }
242 virtual void didDownloadData(int) { }
244 double loadFinishTime() const { return m_loadFinishTime; }
246 virtual bool canReuse(const ResourceRequest&) const { return true; }
250 static const char* resourceTypeToString(Type, const FetchInitiatorInfo&);
253 virtual void checkNotify();
254 virtual void finishOnePart();
256 // Normal resource pointers will silently switch what Resource* they reference when we
257 // successfully revalidated the resource. We need a way to guarantee that the Resource
258 // that received the 304 response survives long enough to switch everything over to the
259 // revalidatedresource. The normal mechanisms for keeping a Resource alive externally
260 // (ResourcePtrs and ResourceClients registering themselves) don't work in this case, so
261 // have a separate internal protector).
262 class InternalResourcePtr {
264 explicit InternalResourcePtr(Resource* resource)
265 : m_resource(resource)
267 m_resource->incrementProtectorCount();
270 ~InternalResourcePtr()
272 m_resource->decrementProtectorCount();
273 m_resource->deleteIfPossible();
276 Resource* m_resource;
279 void incrementProtectorCount() { m_protectorCount++; }
280 void decrementProtectorCount() { m_protectorCount--; }
282 void setEncodedSize(size_t);
283 void setDecodedSize(size_t);
284 void didAccessDecodedData(double timeStamp);
286 virtual void switchClientsToRevalidatedResource();
287 void clearResourceToRevalidate();
288 void updateResponseAfterRevalidation(const ResourceResponse& validatingResponse);
290 void finishPendingClients();
292 HashCountedSet<ResourceClient*> m_clients;
293 HashCountedSet<ResourceClient*> m_clientsAwaitingCallback;
295 class ResourceCallback {
297 static ResourceCallback* callbackHandler();
298 void schedule(Resource*);
299 void cancel(Resource*);
302 void timerFired(Timer<ResourceCallback>*);
303 Timer<ResourceCallback> m_callbackTimer;
304 HashSet<Resource*> m_resourcesWithPendingClients;
307 bool hasClient(ResourceClient* client) { return m_clients.contains(client) || m_clientsAwaitingCallback.contains(client); }
309 struct RedirectPair {
311 explicit RedirectPair(const ResourceRequest& request, const ResourceResponse& redirectResponse)
313 , m_redirectResponse(redirectResponse)
317 const ResourceRequest m_request;
318 const ResourceResponse m_redirectResponse;
320 const Vector<RedirectPair>& redirectChain() const { return m_redirectChain; }
322 virtual bool isSafeToUnlock() const { return false; }
323 virtual void destroyDecodedDataIfPossible() { }
325 ResourceRequest m_resourceRequest;
326 AtomicString m_accept;
327 RefPtr<ResourceLoader> m_loader;
328 ResourceLoaderOptions m_options;
330 ResourceResponse m_response;
331 double m_responseTimestamp;
333 RefPtr<SharedBuffer> m_data;
334 OwnPtr<PurgeableBuffer> m_purgeableData;
335 Timer<Resource> m_cancelTimer;
338 bool addClientToSet(ResourceClient*);
339 void cancelTimerFired(Timer<Resource>*);
341 void revalidationSucceeded(const ResourceResponse&);
342 void revalidationFailed();
346 void failBeforeStarting();
348 String m_fragmentIdentifierForRequest;
350 RefPtr<CachedMetadata> m_cachedMetadata;
352 ResourceError m_error;
354 double m_lastDecodedAccessTime; // Used as a "thrash guard" in the cache
355 double m_loadFinishTime;
357 unsigned long m_identifier;
359 size_t m_encodedSize;
360 size_t m_decodedSize;
361 unsigned m_accessCount;
362 unsigned m_handleCount;
363 unsigned m_preloadCount;
364 unsigned m_protectorCount;
366 unsigned m_preloadResult : 2; // PreloadResult
367 unsigned m_cacheLiveResourcePriority : 2; // CacheLiveResourcePriority
368 unsigned m_inLiveDecodedResourcesList : 1;
369 unsigned m_requestedFromNetworkingLayer : 1;
371 unsigned m_inCache : 1;
372 unsigned m_loading : 1;
374 unsigned m_switchingClientsToRevalidatedResource : 1;
376 unsigned m_type : 4; // Type
377 unsigned m_status : 3; // Status
379 unsigned m_wasPurged : 1;
381 unsigned m_needsSynchronousCacheHit : 1;
388 Resource* m_nextInAllResourcesList;
389 Resource* m_prevInAllResourcesList;
391 Resource* m_nextInLiveResourcesList;
392 Resource* m_prevInLiveResourcesList;
394 // If this field is non-null we are using the resource as a proxy for checking whether an existing resource is still up to date
395 // using HTTP If-Modified-Since/If-None-Match headers. If the response is 304 all clients of this resource are moved
396 // to to be clients of m_resourceToRevalidate and the resource is deleted. If not, the field is zeroed and this
397 // resources becomes normal resource load.
398 Resource* m_resourceToRevalidate;
400 // If this field is non-null, the resource has a proxy for checking whether it is still up to date (see m_resourceToRevalidate).
401 Resource* m_proxyResource;
403 // These handles will need to be updated to point to the m_resourceToRevalidate in case we get 304 response.
404 HashSet<ResourcePtrBase*> m_handlesToRevalidate;
406 // Ordered list of all redirects followed while fetching this resource.
407 Vector<RedirectPair> m_redirectChain;
411 // Intended to be used in LOG statements.
412 const char* ResourceTypeName(Resource::Type);
415 #define DEFINE_RESOURCE_TYPE_CASTS(typeName) \
416 DEFINE_TYPE_CASTS(typeName##Resource, Resource, resource, resource->type() == Resource::typeName, resource.type() == Resource::typeName); \
417 inline typeName##Resource* to##typeName##Resource(const ResourcePtr<Resource>& ptr) { return to##typeName##Resource(ptr.get()); }