third_party/WebKit/Source/core/fetch/Resource.h

   1 /*
   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.
   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
  23 #ifndef Resource_h
  24 #define Resource_h
  25
  26 #include "core/CoreExport.h"
  27 #include "core/fetch/CachedMetadataHandler.h"
  28 #include "core/fetch/ResourceLoaderOptions.h"
  29 #include "platform/Timer.h"
  30 #include "platform/network/ResourceError.h"
  31 #include "platform/network/ResourceLoadPriority.h"
  32 #include "platform/network/ResourceRequest.h"
  33 #include "platform/network/ResourceResponse.h"
  34 #include "public/platform/WebDataConsumerHandle.h"
  35 #include "wtf/Allocator.h"
  36 #include "wtf/HashCountedSet.h"
  37 #include "wtf/HashSet.h"
  38 #include "wtf/OwnPtr.h"
  39 #include "wtf/text/WTFString.h"
  40
  41 // FIXME(crbug.com/352043): This is temporarily enabled even on RELEASE to diagnose a wild crash.
  42 #define ENABLE_RESOURCE_IS_DELETED_CHECK
  43
  44 namespace blink {
  45
  46 struct FetchInitiatorInfo;
  47 class CachedMetadata;
  48 class ResourceClient;
  49 class ResourcePtrBase;
  50 class ResourceFetcher;
  51 class ResourceTimingInfo;
  52 class InspectorResource;
  53 class ResourceLoader;
  54 class SecurityOrigin;
  55 class SharedBuffer;
  56
  57 // A resource that is held in the cache. Classes who want to use this object should derive
  58 // from ResourceClient, to get the function calls in case the requested data has arrived.
  59 // This class also does the actual communication with the loader to obtain the resource from the network.
  60 class CORE_EXPORT Resource : public NoBaseWillBeGarbageCollectedFinalized<Resource> {
  61     WTF_MAKE_NONCOPYABLE(Resource); WTF_MAKE_FAST_ALLOCATED_WILL_BE_REMOVED(Resource);
  62     friend class InspectorResource;
  63
  64 public:
  65     enum Type {
  66         MainResource,
  67         Image,
  68         CSSStyleSheet,
  69         Script,
  70         Font,
  71         Raw,
  72         SVGDocument,
  73         XSLStyleSheet,
  74         LinkPrefetch,
  75         LinkSubresource,
  76         LinkPreload,
  77         TextTrack,
  78         ImportResource,
  79         Media // Audio or video file requested by a HTML5 media element
  80     };
  81
  82     enum Status {
  83         Unknown, // let cache decide what to do with it
  84         Pending, // only partially loaded
  85         Cached, // regular case
  86         LoadError,
  87         DecodeError
  88     };
  89
  90     // Exposed for testing.
  91     Resource(const ResourceRequest&, Type);
  92 #if ENABLE(OILPAN)
  93     virtual ~Resource();
  94 #else
  95 protected:
  96     // Only deleteIfPossible should delete this.
  97     virtual ~Resource();
  98 public:
  99 #endif
 100     virtual void dispose();
 101     DECLARE_VIRTUAL_TRACE();
 102
 103     virtual void load(ResourceFetcher*, const ResourceLoaderOptions&);
 104
 105     virtual void setEncoding(const String&) { }
 106     virtual String encoding() const { return String(); }
 107     virtual void appendData(const char*, unsigned);
 108     virtual void error(Resource::Status);
 109     virtual void setCORSFailed() { }
 110
 111     void setNeedsSynchronousCacheHit(bool needsSynchronousCacheHit) { m_needsSynchronousCacheHit = needsSynchronousCacheHit; }
 112
 113     void setResourceError(const ResourceError& error) { m_error = error; }
 114     const ResourceError& resourceError() const { return m_error; }
 115
 116     void setIdentifier(unsigned long identifier) { m_identifier = identifier; }
 117     unsigned long identifier() const { return m_identifier; }
 118
 119     virtual bool shouldIgnoreHTTPStatusCodeErrors() const { return false; }
 120
 121     ResourceRequest& mutableResourceRequest() { return m_resourceRequest; }
 122     const ResourceRequest& resourceRequest() const { return m_resourceRequest; }
 123     const ResourceRequest& lastResourceRequest() const;
 124
 125     const KURL& url() const { return m_resourceRequest.url();}
 126     Type type() const { return static_cast<Type>(m_type); }
 127     const ResourceLoaderOptions& options() const { return m_options; }
 128     void setOptions(const ResourceLoaderOptions& options) { m_options = options; }
 129
 130     void didChangePriority(ResourceLoadPriority, int intraPriorityValue);
 131
 132     void addClient(ResourceClient*);
 133     void removeClient(ResourceClient*);
 134     bool hasClients() const { return !m_clients.isEmpty() || !m_clientsAwaitingCallback.isEmpty(); }
 135     bool deleteIfPossible();
 136
 137     enum PreloadResult {
 138         PreloadNotReferenced,
 139         PreloadReferenced,
 140         PreloadReferencedWhileLoading,
 141         PreloadReferencedWhileComplete
 142     };
 143     PreloadResult preloadResult() const { return static_cast<PreloadResult>(m_preloadResult); }
 144
 145     virtual void didAddClient(ResourceClient*);
 146     virtual void didRemoveClient(ResourceClient*) { }
 147     virtual void allClientsRemoved();
 148
 149     unsigned count() const { return m_clients.size(); }
 150
 151     Status status() const { return static_cast<Status>(m_status); }
 152     void setStatus(Status status) { m_status = status; }
 153
 154     size_t size() const { return encodedSize() + decodedSize() + overheadSize(); }
 155     size_t encodedSize() const { return m_encodedSize; }
 156     size_t decodedSize() const { return m_decodedSize; }
 157     size_t overheadSize() const;
 158
 159     bool isLoaded() const { return !m_loading; } // FIXME. Method name is inaccurate. Loading might not have started yet.
 160
 161     bool isLoading() const { return m_loading; }
 162     void setLoading(bool b) { m_loading = b; }
 163     virtual bool stillNeedsLoad() const { return false; }
 164
 165     ResourceLoader* loader() const { return m_loader.get(); }
 166
 167     virtual bool isImage() const { return false; }
 168     bool shouldBlockLoadEvent() const
 169     {
 170         return type() != LinkPrefetch
 171             && type() != LinkSubresource
 172             && type() != Media
 173             && type() != Raw
 174             && type() != TextTrack;
 175     }
 176
 177     // Computes the status of an object after loading.
 178     // Updates the expire date on the cache entry file
 179     void setLoadFinishTime(double finishTime) { m_loadFinishTime = finishTime; }
 180     void finish();
 181
 182     // FIXME: Remove the stringless variant once all the callsites' error messages are updated.
 183     bool passesAccessControlCheck(SecurityOrigin*) const;
 184     bool passesAccessControlCheck(SecurityOrigin*, String& errorDescription) const;
 185
 186     bool isEligibleForIntegrityCheck(SecurityOrigin*) const;
 187
 188     void clearLoader();
 189
 190     SharedBuffer* resourceBuffer() const { return m_data.get(); }
 191     void setResourceBuffer(PassRefPtr<SharedBuffer>);
 192
 193     virtual void willFollowRedirect(ResourceRequest&, const ResourceResponse&);
 194
 195     virtual void updateRequest(const ResourceRequest&) { }
 196     virtual void responseReceived(const ResourceResponse&, PassOwnPtr<WebDataConsumerHandle>);
 197     void setResponse(const ResourceResponse& response) { m_response = response; }
 198     const ResourceResponse& response() const { return m_response; }
 199
 200     virtual void reportResourceTimingToClients(const ResourceTimingInfo&) { }
 201
 202     // Sets the serialized metadata retrieved from the platform's cache.
 203     virtual void setSerializedCachedMetadata(const char*, size_t);
 204
 205     // This may return nullptr when the resource isn't cacheable.
 206     CachedMetadataHandler* cacheHandler();
 207
 208     bool hasOneHandle() const;
 209     bool canDelete() const;
 210
 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; }
 215
 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(); }
 219
 220     DataBufferingPolicy dataBufferingPolicy() const { return m_options.dataBufferingPolicy; }
 221     void setDataBufferingPolicy(DataBufferingPolicy);
 222
 223     bool isUnusedPreload() const { return isPreloaded() && preloadResult() == PreloadNotReferenced; }
 224     bool isPreloaded() const { return m_preloadCount; }
 225     void increasePreloadCount() { ++m_preloadCount; }
 226     void decreasePreloadCount() { ASSERT(m_preloadCount); --m_preloadCount; }
 227
 228     void registerHandle(ResourcePtrBase* h);
 229     void unregisterHandle(ResourcePtrBase* h);
 230
 231     bool canReuseRedirectChain();
 232     bool mustRevalidateDueToCacheHeaders();
 233     bool canUseCacheValidator();
 234     bool isCacheValidator() const { return m_resourceToRevalidate; }
 235     Resource* resourceToRevalidate() const { return m_resourceToRevalidate; }
 236     void setResourceToRevalidate(Resource*);
 237     bool hasCacheControlNoStoreHeader();
 238     bool hasVaryHeader() const;
 239
 240     double currentAge() const;
 241     double freshnessLifetime();
 242     double stalenessLifetime();
 243
 244     bool isPurgeable() const;
 245     bool wasPurged() const;
 246     bool lock();
 247
 248     void setCacheIdentifier(const String& cacheIdentifier) { m_cacheIdentifier = cacheIdentifier; }
 249     String cacheIdentifier() const { return m_cacheIdentifier; }
 250
 251     virtual void didSendData(unsigned long long /* bytesSent */, unsigned long long /* totalBytesToBeSent */) { }
 252     virtual void didDownloadData(int) { }
 253
 254     double loadFinishTime() const { return m_loadFinishTime; }
 255
 256     virtual bool canReuse(const ResourceRequest&) const { return true; }
 257
 258     // Used by the MemoryCache to reduce the memory consumption of the entry.
 259     void prune();
 260
 261     static const char* resourceTypeToString(Type, const FetchInitiatorInfo&);
 262
 263 #ifdef ENABLE_RESOURCE_IS_DELETED_CHECK
 264     void assertAlive() const { RELEASE_ASSERT(!m_deleted); }
 265 #else
 266     void assertAlive() const { }
 267 #endif
 268
 269 protected:
 270     virtual void checkNotify();
 271     virtual void finishOnePart();
 272
 273     // Normal resource pointers will silently switch what Resource* they reference when we
 274     // successfully revalidated the resource. We need a way to guarantee that the Resource
 275     // that received the 304 response survives long enough to switch everything over to the
 276     // revalidatedresource. The normal mechanisms for keeping a Resource alive externally
 277     // (ResourcePtrs and ResourceClients registering themselves) don't work in this case, so
 278     // have a separate internal protector).
 279     class InternalResourcePtr {
 280     public:
 281         explicit InternalResourcePtr(Resource* resource)
 282             : m_resource(resource)
 283         {
 284             m_resource->incrementProtectorCount();
 285         }
 286
 287         ~InternalResourcePtr()
 288         {
 289             m_resource->decrementProtectorCount();
 290             m_resource->deleteIfPossible();
 291         }
 292     private:
 293         Resource* m_resource;
 294     };
 295
 296     void incrementProtectorCount() { m_protectorCount++; }
 297     void decrementProtectorCount() { m_protectorCount--; }
 298
 299     void setEncodedSize(size_t);
 300     void setDecodedSize(size_t);
 301     void didAccessDecodedData();
 302
 303     void clearResourceToRevalidate();
 304     void updateResponseAfterRevalidation(const ResourceResponse& validatingResponse);
 305
 306     void finishPendingClients();
 307
 308     HashCountedSet<ResourceClient*> m_clients;
 309     HashCountedSet<ResourceClient*> m_clientsAwaitingCallback;
 310
 311     class ResourceCallback : public NoBaseWillBeGarbageCollectedFinalized<ResourceCallback> {
 312     public:
 313         static ResourceCallback* callbackHandler();
 314         DECLARE_TRACE();
 315         void schedule(Resource*);
 316         void cancel(Resource*);
 317         bool isScheduled(Resource*) const;
 318     private:
 319         ResourceCallback();
 320         void timerFired(Timer<ResourceCallback>*);
 321         Timer<ResourceCallback> m_callbackTimer;
 322         WillBeHeapHashSet<RawPtrWillBeMember<Resource>> m_resourcesWithPendingClients;
 323     };
 324
 325     bool hasClient(ResourceClient* client) { return m_clients.contains(client) || m_clientsAwaitingCallback.contains(client); }
 326
 327     struct RedirectPair {
 328         ALLOW_ONLY_INLINE_ALLOCATION();
 329     public:
 330         explicit RedirectPair(const ResourceRequest& request, const ResourceResponse& redirectResponse)
 331             : m_request(request)
 332             , m_redirectResponse(redirectResponse)
 333         {
 334         }
 335
 336         ResourceRequest m_request;
 337         ResourceResponse m_redirectResponse;
 338     };
 339     const Vector<RedirectPair>& redirectChain() const { return m_redirectChain; }
 340
 341     virtual bool isSafeToUnlock() const { return false; }
 342     virtual void destroyDecodedDataIfPossible() { }
 343
 344     ResourceRequest m_resourceRequest;
 345     AtomicString m_accept;
 346     PersistentWillBeMember<ResourceLoader> m_loader;
 347     ResourceLoaderOptions m_options;
 348
 349     ResourceResponse m_response;
 350     double m_responseTimestamp;
 351
 352     RefPtr<SharedBuffer> m_data;
 353     Timer<Resource> m_cancelTimer;
 354
 355 private:
 356     class CacheHandler;
 357     bool addClientToSet(ResourceClient*);
 358     void cancelTimerFired(Timer<Resource>*);
 359
 360     void switchClientsToRevalidatedResource();
 361     void revalidationSucceeded(const ResourceResponse&);
 362     void revalidationFailed();
 363
 364     bool unlock();
 365
 366     bool hasRightHandleCountApartFromCache(unsigned targetCount) const;
 367
 368     void setCachedMetadata(unsigned dataTypeID, const char*, size_t, CachedMetadataHandler::CacheType);
 369     void clearCachedMetadata(CachedMetadataHandler::CacheType);
 370     CachedMetadata* cachedMetadata(unsigned dataTypeID) const;
 371
 372     String m_fragmentIdentifierForRequest;
 373
 374     RefPtr<CachedMetadata> m_cachedMetadata;
 375     OwnPtrWillBeMember<CacheHandler> m_cacheHandler;
 376
 377     ResourceError m_error;
 378
 379     double m_loadFinishTime;
 380
 381     unsigned long m_identifier;
 382
 383     size_t m_encodedSize;
 384     size_t m_decodedSize;
 385     unsigned m_handleCount;
 386     unsigned m_preloadCount;
 387     unsigned m_protectorCount;
 388
 389     String m_cacheIdentifier;
 390
 391     unsigned m_preloadResult : 2; // PreloadResult
 392     unsigned m_requestedFromNetworkingLayer : 1;
 393
 394     unsigned m_loading : 1;
 395
 396     unsigned m_switchingClientsToRevalidatedResource : 1;
 397
 398     unsigned m_type : 4; // Type
 399     unsigned m_status : 3; // Status
 400
 401     unsigned m_wasPurged : 1;
 402
 403     unsigned m_needsSynchronousCacheHit : 1;
 404
 405 #ifdef ENABLE_RESOURCE_IS_DELETED_CHECK
 406     bool m_deleted;
 407 #endif
 408
 409     // 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
 410     // using HTTP If-Modified-Since/If-None-Match headers. If the response is 304 all clients of this resource are moved
 411     // to to be clients of m_resourceToRevalidate and the resource is deleted. If not, the field is zeroed and this
 412     // resources becomes normal resource load.
 413     RawPtrWillBeMember<Resource> m_resourceToRevalidate;
 414
 415     // If this field is non-null, the resource has a proxy for checking whether it is still up to date (see m_resourceToRevalidate).
 416     RawPtrWillBeMember<Resource> m_proxyResource;
 417
 418     // These handles will need to be updated to point to the m_resourceToRevalidate in case we get 304 response.
 419     HashSet<ResourcePtrBase*> m_handlesToRevalidate;
 420
 421     // Ordered list of all redirects followed while fetching this resource.
 422     Vector<RedirectPair> m_redirectChain;
 423 };
 424
 425 class ResourceFactory {
 426     STACK_ALLOCATED();
 427 public:
 428     virtual Resource* create(const ResourceRequest&, const String&) const = 0;
 429     Resource::Type type() const { return m_type; }
 430
 431 protected:
 432     ResourceFactory(Resource::Type type) : m_type(type) { }
 433
 434     Resource::Type m_type;
 435 };
 436
 437 #if !LOG_DISABLED
 438 // Intended to be used in LOG statements.
 439 const char* ResourceTypeName(Resource::Type);
 440 #endif
 441
 442 #define DEFINE_RESOURCE_TYPE_CASTS(typeName) \
 443     DEFINE_TYPE_CASTS(typeName##Resource, Resource, resource, resource->type() == Resource::typeName, resource.type() == Resource::typeName); \
 444     inline typeName##Resource* to##typeName##Resource(const ResourcePtr<Resource>& ptr) { return to##typeName##Resource(ptr.get()); }
 445
 446 }
 447
 448 #endif