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#pragma once
24
25#include "CachePolicy.h"
26#include "CacheValidation.h"
27#include "FrameLoaderTypes.h"
28#include "ResourceError.h"
29#include "ResourceLoadPriority.h"
30#include "ResourceLoaderOptions.h"
31#include "ResourceRequest.h"
32#include "ResourceResponse.h"
33#include "Timer.h"
34#include <pal/SessionID.h>
35#include <time.h>
36#include <wtf/HashCountedSet.h>
37#include <wtf/HashSet.h>
38#include <wtf/TypeCasts.h>
39#include <wtf/Vector.h>
40#include <wtf/text/WTFString.h>
41
42namespace WebCore {
43
44class CachedResourceClient;
45class CachedResourceHandleBase;
46class CachedResourceLoader;
47class CachedResourceRequest;
48class CookieJar;
49class LoadTiming;
50class MemoryCache;
51class SecurityOrigin;
52class SharedBuffer;
53class SubresourceLoader;
54class TextResourceDecoder;
55
56// A resource that is held in the cache. Classes who want to use this object should derive
57// from CachedResourceClient, to get the function calls in case the requested data has arrived.
58// This class also does the actual communication with the loader to obtain the resource from the network.
59class CachedResource {
60 WTF_MAKE_NONCOPYABLE(CachedResource); WTF_MAKE_FAST_ALLOCATED;
61 friend class MemoryCache;
62
63public:
64 enum class Type : uint8_t {
65 MainResource,
66 ImageResource,
67 CSSStyleSheet,
68 Script,
69 FontResource,
70#if ENABLE(SVG_FONTS)
71 SVGFontResource,
72#endif
73 MediaResource,
74 RawResource,
75 Icon,
76 Beacon,
77 Ping,
78 SVGDocumentResource
79#if ENABLE(XSLT)
80 , XSLStyleSheet
81#endif
82 , LinkPrefetch
83#if ENABLE(VIDEO_TRACK)
84 , TextTrackResource
85#endif
86#if ENABLE(APPLICATION_MANIFEST)
87 , ApplicationManifest
88#endif
89 };
90
91 enum Status {
92 Unknown, // let cache decide what to do with it
93 Pending, // only partially loaded
94 Cached, // regular case
95 LoadError,
96 DecodeError
97 };
98
99 CachedResource(CachedResourceRequest&&, Type, const PAL::SessionID&, const CookieJar*);
100 virtual ~CachedResource();
101
102 virtual void load(CachedResourceLoader&);
103
104 virtual void setEncoding(const String&) { }
105 virtual String encoding() const { return String(); }
106 virtual const TextResourceDecoder* textResourceDecoder() const { return nullptr; }
107 virtual void updateBuffer(SharedBuffer&);
108 virtual void updateData(const char* data, unsigned length);
109 virtual void finishLoading(SharedBuffer*);
110 virtual void error(CachedResource::Status);
111
112 void setResourceError(const ResourceError& error) { m_error = error; }
113 const ResourceError& resourceError() const { return m_error; }
114
115 virtual bool shouldIgnoreHTTPStatusCodeErrors() const { return false; }
116
117 const ResourceRequest& resourceRequest() const { return m_resourceRequest; }
118 const URL& url() const { return m_resourceRequest.url();}
119 const String& cachePartition() const { return m_resourceRequest.cachePartition(); }
120 PAL::SessionID sessionID() const { return m_sessionID; }
121 const CookieJar* cookieJar() const { return m_cookieJar.get(); }
122 Type type() const { return m_type; }
123 String mimeType() const { return m_response.mimeType(); }
124 long long expectedContentLength() const { return m_response.expectedContentLength(); }
125
126 static bool shouldUsePingLoad(Type type) { return type == Type::Beacon || type == Type::Ping; }
127
128 ResourceLoadPriority loadPriority() const { return m_loadPriority; }
129 void setLoadPriority(const Optional<ResourceLoadPriority>&);
130
131 WEBCORE_EXPORT void addClient(CachedResourceClient&);
132 WEBCORE_EXPORT void removeClient(CachedResourceClient&);
133 bool hasClients() const { return !m_clients.isEmpty() || !m_clientsAwaitingCallback.isEmpty(); }
134 bool hasClient(CachedResourceClient& client) { return m_clients.contains(&client) || m_clientsAwaitingCallback.contains(&client); }
135 bool deleteIfPossible();
136
137 enum class PreloadResult : uint8_t {
138 PreloadNotReferenced,
139 PreloadReferenced,
140 PreloadReferencedWhileLoading,
141 PreloadReferencedWhileComplete
142 };
143 PreloadResult preloadResult() const { return static_cast<PreloadResult>(m_preloadResult); }
144
145 virtual void didAddClient(CachedResourceClient&);
146 virtual void didRemoveClient(CachedResourceClient&) { }
147 virtual void allClientsRemoved();
148 void destroyDecodedDataIfNeeded();
149
150 unsigned numberOfClients() const { return m_clients.size(); }
151
152 Status status() const { return static_cast<Status>(m_status); }
153 void setStatus(Status status) { m_status = status; }
154
155 unsigned size() const { return encodedSize() + decodedSize() + overheadSize(); }
156 unsigned encodedSize() const { return m_encodedSize; }
157 unsigned decodedSize() const { return m_decodedSize; }
158 unsigned overheadSize() const;
159
160 bool isLoaded() const { return !m_loading; } // FIXME. Method name is inaccurate. Loading might not have started yet.
161
162 bool isLoading() const { return m_loading; }
163 void setLoading(bool b) { m_loading = b; }
164 virtual bool stillNeedsLoad() const { return false; }
165
166 SubresourceLoader* loader() { return m_loader.get(); }
167
168 bool areAllClientsXMLHttpRequests() const;
169
170 bool isImage() const { return type() == Type::ImageResource; }
171 // FIXME: CachedRawResource could be a main resource, an audio/video resource, or a raw XHR/icon resource.
172 bool isMainOrMediaOrIconOrRawResource() const { return type() == Type::MainResource || type() == Type::MediaResource || type() == Type::Icon || type() == Type::RawResource || type() == Type::Beacon || type() == Type::Ping; }
173
174 // Whether this request should impact request counting and delay window.onload.
175 bool ignoreForRequestCount() const
176 {
177 return m_ignoreForRequestCount
178 || type() == Type::MainResource
179 || type() == Type::LinkPrefetch
180 || type() == Type::Beacon
181 || type() == Type::Ping
182 || type() == Type::Icon
183 || type() == Type::RawResource;
184 }
185
186 void setIgnoreForRequestCount(bool ignoreForRequestCount) { m_ignoreForRequestCount = ignoreForRequestCount; }
187
188 unsigned accessCount() const { return m_accessCount; }
189 void increaseAccessCount() { m_accessCount++; }
190
191 // Computes the status of an object after loading.
192 // Updates the expire date on the cache entry file
193 void finish();
194
195 // Called by the cache if the object has been removed from the cache
196 // while still being referenced. This means the object should delete itself
197 // if the number of clients observing it ever drops to 0.
198 // The resource can be brought back to cache after successful revalidation.
199 void setInCache(bool inCache) { m_inCache = inCache; }
200 bool inCache() const { return m_inCache; }
201
202 void clearLoader();
203
204 SharedBuffer* resourceBuffer() const { return m_data.get(); }
205
206 virtual void redirectReceived(ResourceRequest&&, const ResourceResponse&, CompletionHandler<void(ResourceRequest&&)>&&);
207 virtual void responseReceived(const ResourceResponse&);
208 virtual bool shouldCacheResponse(const ResourceResponse&) { return true; }
209 void setResponse(const ResourceResponse&);
210 const ResourceResponse& response() const { return m_response; }
211
212 void setCrossOrigin();
213 bool isCrossOrigin() const;
214 bool isCORSSameOrigin() const;
215 ResourceResponse::Tainting responseTainting() const { return m_responseTainting; }
216
217 void loadFrom(const CachedResource&);
218
219 SecurityOrigin* origin() const { return m_origin.get(); }
220 AtomicString initiatorName() const { return m_initiatorName; }
221
222 bool canDelete() const { return !hasClients() && !m_loader && !m_preloadCount && !m_handleCount && !m_resourceToRevalidate && !m_proxyResource; }
223 bool hasOneHandle() const { return m_handleCount == 1; }
224
225 bool isExpired() const;
226
227 void cancelLoad();
228 bool wasCanceled() const { return m_error.isCancellation(); }
229 bool errorOccurred() const { return m_status == LoadError || m_status == DecodeError; }
230 bool loadFailedOrCanceled() const { return !m_error.isNull(); }
231
232 bool shouldSendResourceLoadCallbacks() const { return m_options.sendLoadCallbacks == SendCallbackPolicy::SendCallbacks; }
233 DataBufferingPolicy dataBufferingPolicy() const { return m_options.dataBufferingPolicy; }
234
235 bool allowsCaching() const { return m_options.cachingPolicy == CachingPolicy::AllowCaching; }
236 const ResourceLoaderOptions& options() const { return m_options; }
237
238 virtual void destroyDecodedData() { }
239
240 bool isPreloaded() const { return m_preloadCount; }
241 void increasePreloadCount() { ++m_preloadCount; }
242 void decreasePreloadCount() { ASSERT(m_preloadCount); --m_preloadCount; }
243 bool isLinkPreload() { return m_isLinkPreload; }
244 void setLinkPreload() { m_isLinkPreload = true; }
245 bool hasUnknownEncoding() { return m_hasUnknownEncoding; }
246 void setHasUnknownEncoding(bool hasUnknownEncoding) { m_hasUnknownEncoding = hasUnknownEncoding; }
247
248 void registerHandle(CachedResourceHandleBase*);
249 WEBCORE_EXPORT void unregisterHandle(CachedResourceHandleBase*);
250
251 bool canUseCacheValidator() const;
252
253 enum class RevalidationDecision { No, YesDueToCachePolicy, YesDueToNoStore, YesDueToNoCache, YesDueToExpired };
254 virtual RevalidationDecision makeRevalidationDecision(CachePolicy) const;
255 bool redirectChainAllowsReuse(ReuseExpiredRedirectionOrNot) const;
256 bool hasRedirections() const { return m_redirectChainCacheStatus.status != RedirectChainCacheStatus::Status::NoRedirection; }
257
258 bool varyHeaderValuesMatch(const ResourceRequest&);
259
260 bool isCacheValidator() const { return m_resourceToRevalidate; }
261 CachedResource* resourceToRevalidate() const { return m_resourceToRevalidate; }
262
263 // HTTP revalidation support methods for CachedResourceLoader.
264 void setResourceToRevalidate(CachedResource*);
265 virtual void switchClientsToRevalidatedResource();
266 void clearResourceToRevalidate();
267 void updateResponseAfterRevalidation(const ResourceResponse& validatingResponse);
268 bool validationInProgress() const { return m_proxyResource; }
269 bool validationCompleting() const { return m_proxyResource && m_proxyResource->m_switchingClientsToRevalidatedResource; }
270
271 virtual void didSendData(unsigned long long /* bytesSent */, unsigned long long /* totalBytesToBeSent */) { }
272
273#if USE(FOUNDATION) || USE(SOUP)
274 WEBCORE_EXPORT void tryReplaceEncodedData(SharedBuffer&);
275#endif
276
277 unsigned long identifierForLoadWithoutResourceLoader() const { return m_identifierForLoadWithoutResourceLoader; }
278 static ResourceLoadPriority defaultPriorityForResourceType(Type);
279
280 void setOriginalRequest(std::unique_ptr<ResourceRequest>&& originalRequest) { m_originalRequest = WTFMove(originalRequest); }
281 const std::unique_ptr<ResourceRequest>& originalRequest() const { return m_originalRequest; }
282
283protected:
284 // CachedResource constructor that may be used when the CachedResource can already be filled with response data.
285 CachedResource(const URL&, Type, const PAL::SessionID&, const CookieJar*);
286
287 void setEncodedSize(unsigned);
288 void setDecodedSize(unsigned);
289 void didAccessDecodedData(MonotonicTime timeStamp);
290
291 virtual void didReplaceSharedBufferContents() { }
292
293 virtual void setBodyDataFrom(const CachedResource&);
294
295private:
296 class Callback;
297
298 bool addClientToSet(CachedResourceClient&);
299
300 void decodedDataDeletionTimerFired();
301
302 virtual void checkNotify();
303 virtual bool mayTryReplaceEncodedData() const { return false; }
304
305 Seconds freshnessLifetime(const ResourceResponse&) const;
306
307 void addAdditionalRequestHeaders(CachedResourceLoader&);
308 void failBeforeStarting();
309
310protected:
311 ResourceLoaderOptions m_options;
312 ResourceRequest m_resourceRequest;
313 ResourceResponse m_response;
314
315 DeferrableOneShotTimer m_decodedDataDeletionTimer;
316
317 // FIXME: Make the rest of these data members private and use functions in derived classes instead.
318 HashCountedSet<CachedResourceClient*> m_clients;
319 std::unique_ptr<ResourceRequest> m_originalRequest; // Needed by Ping loads.
320 RefPtr<SubresourceLoader> m_loader;
321 RefPtr<SharedBuffer> m_data;
322
323private:
324 MonotonicTime m_lastDecodedAccessTime; // Used as a "thrash guard" in the cache
325 PAL::SessionID m_sessionID;
326 RefPtr<const CookieJar> m_cookieJar;
327 WallTime m_responseTimestamp;
328 unsigned long m_identifierForLoadWithoutResourceLoader { 0 };
329
330 HashMap<CachedResourceClient*, std::unique_ptr<Callback>> m_clientsAwaitingCallback;
331
332 // These handles will need to be updated to point to the m_resourceToRevalidate in case we get 304 response.
333 HashSet<CachedResourceHandleBase*> m_handlesToRevalidate;
334
335 Vector<std::pair<String, String>> m_varyingHeaderValues;
336
337 // 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
338 // using HTTP If-Modified-Since/If-None-Match headers. If the response is 304 all clients of this resource are moved
339 // to to be clients of m_resourceToRevalidate and the resource is deleted. If not, the field is zeroed and this
340 // resources becomes normal resource load.
341 CachedResource* m_resourceToRevalidate { nullptr };
342
343 // If this field is non-null, the resource has a proxy for checking whether it is still up to date (see m_resourceToRevalidate).
344 CachedResource* m_proxyResource { nullptr };
345
346 String m_fragmentIdentifierForRequest;
347
348 ResourceError m_error;
349 RefPtr<SecurityOrigin> m_origin;
350 AtomicString m_initiatorName;
351
352 RedirectChainCacheStatus m_redirectChainCacheStatus;
353
354 unsigned m_encodedSize { 0 };
355 unsigned m_decodedSize { 0 };
356 unsigned m_accessCount { 0 };
357 unsigned m_handleCount { 0 };
358 unsigned m_preloadCount { 0 };
359
360 unsigned m_status { Pending }; // Status
361
362 PreloadResult m_preloadResult { PreloadResult::PreloadNotReferenced };
363
364 ResourceResponse::Tainting m_responseTainting { ResourceResponse::Tainting::Basic };
365 ResourceLoadPriority m_loadPriority;
366
367 Type m_type; // Type
368
369 bool m_requestedFromNetworkingLayer { false };
370 bool m_inCache { false };
371 bool m_loading { false };
372 bool m_isLinkPreload { false };
373 bool m_hasUnknownEncoding { false };
374 bool m_switchingClientsToRevalidatedResource { false };
375 bool m_ignoreForRequestCount { false };
376
377#ifndef NDEBUG
378 bool m_deleted { false };
379 unsigned m_lruIndex { 0 };
380#endif
381};
382
383class CachedResource::Callback {
384#if !COMPILER(MSVC)
385 WTF_MAKE_FAST_ALLOCATED;
386#endif
387public:
388 Callback(CachedResource&, CachedResourceClient&);
389
390 void cancel();
391
392private:
393 void timerFired();
394
395 CachedResource& m_resource;
396 CachedResourceClient& m_client;
397 Timer m_timer;
398};
399
400} // namespace WebCore
401
402#define SPECIALIZE_TYPE_TRAITS_CACHED_RESOURCE(ToClassName, CachedResourceType) \
403SPECIALIZE_TYPE_TRAITS_BEGIN(WebCore::ToClassName) \
404 static bool isType(const WebCore::CachedResource& resource) { return resource.type() == WebCore::CachedResourceType; } \
405SPECIALIZE_TYPE_TRAITS_END()
406