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&) { m_requestedFromNetworkingLayer = true; }
191 virtual void updateRequest(const ResourceRequest&) { }
192 virtual void responseReceived(const ResourceResponse&);
193 void setResponse(const ResourceResponse& response) { m_response = response; }
194 const ResourceResponse& response() const { return m_response; }
196 // Sets the serialized metadata retrieved from the platform's cache.
197 void setSerializedCachedMetadata(const char*, size_t);
199 // Caches the given metadata in association with this resource and suggests
200 // that the platform persist it. The dataTypeID is a pseudo-randomly chosen
201 // identifier that is used to distinguish data generated by the caller.
202 void setCachedMetadata(unsigned dataTypeID, const char*, size_t);
204 // Returns cached metadata of the given type associated with this resource.
205 CachedMetadata* cachedMetadata(unsigned dataTypeID) const;
207 bool canDelete() const { return !hasClients() && !m_loader && !m_preloadCount && !m_handleCount && !m_protectorCount && !m_resourceToRevalidate && !m_proxyResource; }
208 bool hasOneHandle() const { return m_handleCount == 1; }
210 bool isExpired() const;
212 // List of acceptable MIME types separated by ",".
213 // A MIME type may contain a wildcard, e.g. "text/*".
214 AtomicString accept() const { return m_accept; }
215 void setAccept(const AtomicString& accept) { m_accept = accept; }
217 bool wasCanceled() const { return m_error.isCancellation(); }
218 bool errorOccurred() const { return m_status == LoadError || m_status == DecodeError; }
219 bool loadFailedOrCanceled() { return !m_error.isNull(); }
221 DataBufferingPolicy dataBufferingPolicy() const { return m_options.dataBufferingPolicy; }
222 void setDataBufferingPolicy(DataBufferingPolicy);
224 virtual void destroyDecodedData() { }
226 bool isPreloaded() const { return m_preloadCount; }
227 void increasePreloadCount() { ++m_preloadCount; }
228 void decreasePreloadCount() { ASSERT(m_preloadCount); --m_preloadCount; }
230 void registerHandle(ResourcePtrBase* h);
231 void unregisterHandle(ResourcePtrBase* h);
233 bool canUseCacheValidator() const;
234 bool mustRevalidateDueToCacheHeaders() const;
235 bool isCacheValidator() const { return m_resourceToRevalidate; }
236 Resource* resourceToRevalidate() const { return m_resourceToRevalidate; }
237 void setResourceToRevalidate(Resource*);
239 bool isPurgeable() const;
240 bool wasPurged() const;
242 // This is used by the archive machinery to get at a purged resource without
243 // triggering a load. We should make it protected again if we can find a
244 // better way to handle the archive case.
245 bool makePurgeable(bool purgeable);
247 virtual void didSendData(unsigned long long /* bytesSent */, unsigned long long /* totalBytesToBeSent */) { }
248 virtual void didDownloadData(int) { }
250 double loadFinishTime() const { return m_loadFinishTime; }
252 virtual bool canReuse(const ResourceRequest&) const { return true; }
254 static const char* resourceTypeToString(Type, const FetchInitiatorInfo&);
257 virtual void checkNotify();
258 virtual void finishOnePart();
260 // Normal resource pointers will silently switch what Resource* they reference when we
261 // successfully revalidated the resource. We need a way to guarantee that the Resource
262 // that received the 304 response survives long enough to switch everything over to the
263 // revalidatedresource. The normal mechanisms for keeping a Resource alive externally
264 // (ResourcePtrs and ResourceClients registering themselves) don't work in this case, so
265 // have a separate internal protector).
266 class InternalResourcePtr {
268 explicit InternalResourcePtr(Resource* resource)
269 : m_resource(resource)
271 m_resource->incrementProtectorCount();
274 ~InternalResourcePtr()
276 m_resource->decrementProtectorCount();
277 m_resource->deleteIfPossible();
280 Resource* m_resource;
283 void incrementProtectorCount() { m_protectorCount++; }
284 void decrementProtectorCount() { m_protectorCount--; }
286 void setEncodedSize(size_t);
287 void setDecodedSize(size_t);
288 void didAccessDecodedData(double timeStamp);
290 bool isSafeToMakePurgeable() const;
292 virtual void switchClientsToRevalidatedResource();
293 void clearResourceToRevalidate();
294 void updateResponseAfterRevalidation(const ResourceResponse& validatingResponse);
296 void finishPendingClients();
298 HashCountedSet<ResourceClient*> m_clients;
299 HashCountedSet<ResourceClient*> m_clientsAwaitingCallback;
301 class ResourceCallback {
303 static ResourceCallback* callbackHandler();
304 void schedule(Resource*);
305 void cancel(Resource*);
308 void timerFired(Timer<ResourceCallback>*);
309 Timer<ResourceCallback> m_callbackTimer;
310 HashSet<Resource*> m_resourcesWithPendingClients;
313 bool hasClient(ResourceClient* client) { return m_clients.contains(client) || m_clientsAwaitingCallback.contains(client); }
315 ResourceRequest m_resourceRequest;
316 AtomicString m_accept;
317 RefPtr<ResourceLoader> m_loader;
318 ResourceLoaderOptions m_options;
320 ResourceResponse m_response;
321 double m_responseTimestamp;
323 RefPtr<SharedBuffer> m_data;
324 OwnPtr<PurgeableBuffer> m_purgeableData;
325 Timer<Resource> m_cancelTimer;
328 bool addClientToSet(ResourceClient*);
329 void cancelTimerFired(Timer<Resource>*);
331 void revalidationSucceeded(const ResourceResponse&);
332 void revalidationFailed();
334 double currentAge() const;
335 double freshnessLifetime() const;
337 void failBeforeStarting();
339 String m_fragmentIdentifierForRequest;
341 RefPtr<CachedMetadata> m_cachedMetadata;
343 ResourceError m_error;
345 double m_lastDecodedAccessTime; // Used as a "thrash guard" in the cache
346 double m_loadFinishTime;
348 unsigned long m_identifier;
350 size_t m_encodedSize;
351 size_t m_decodedSize;
352 unsigned m_accessCount;
353 unsigned m_handleCount;
354 unsigned m_preloadCount;
355 unsigned m_protectorCount;
357 unsigned m_preloadResult : 2; // PreloadResult
358 unsigned m_cacheLiveResourcePriority : 2; // CacheLiveResourcePriority
359 unsigned m_inLiveDecodedResourcesList : 1;
360 unsigned m_requestedFromNetworkingLayer : 1;
362 unsigned m_inCache : 1;
363 unsigned m_loading : 1;
365 unsigned m_switchingClientsToRevalidatedResource : 1;
367 unsigned m_type : 4; // Type
368 unsigned m_status : 3; // Status
370 unsigned m_wasPurged : 1;
372 unsigned m_needsSynchronousCacheHit : 1;
379 Resource* m_nextInAllResourcesList;
380 Resource* m_prevInAllResourcesList;
382 Resource* m_nextInLiveResourcesList;
383 Resource* m_prevInLiveResourcesList;
385 // 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
386 // using HTTP If-Modified-Since/If-None-Match headers. If the response is 304 all clients of this resource are moved
387 // to to be clients of m_resourceToRevalidate and the resource is deleted. If not, the field is zeroed and this
388 // resources becomes normal resource load.
389 Resource* m_resourceToRevalidate;
391 // If this field is non-null, the resource has a proxy for checking whether it is still up to date (see m_resourceToRevalidate).
392 Resource* m_proxyResource;
394 // These handles will need to be updated to point to the m_resourceToRevalidate in case we get 304 response.
395 HashSet<ResourcePtrBase*> m_handlesToRevalidate;
399 // Intended to be used in LOG statements.
400 const char* ResourceTypeName(Resource::Type);
403 #define DEFINE_RESOURCE_TYPE_CASTS(typeName) \
404 DEFINE_TYPE_CASTS(typeName##Resource, Resource, resource, resource->type() == Resource::typeName, resource.type() == Resource::typeName); \
405 inline typeName##Resource* to##typeName##Resource(const ResourcePtr<Resource>& ptr) { return to##typeName##Resource(ptr.get()); }