image/imgLoader.h
author Henrik Skupin <mail@hskupin.info>
Fri, 30 Nov 2018 13:27:22 +0000
changeset 448968 cd370c35d88d82c719e7b3d70ae1da003c8cb7f6
parent 448947 6f3709b3878117466168c40affa7bca0b60cf75b
child 452446 f0a91d36587266d7454a450c6044d573664fbed5
permissions -rw-r--r--
Bug 1511311 - [marionette] GeckoInstance classes should not overwrite already set custom preferences. r=automatedtester Custom preferences as passed into both classes via the constructor are getting set in the base GeckoInstance class. But both the DesktopInstance and FennecInstance classes could override those custom preferences if they have the same preference set as required preference. As such the custom preference doesn't have any effect. This patch allows both classes to override required prefs with a different value. Differential Revision: https://phabricator.services.mozilla.com/D13522

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef mozilla_image_imgLoader_h
#define mozilla_image_imgLoader_h

#include "mozilla/Attributes.h"
#include "mozilla/Mutex.h"
#include "mozilla/UniquePtr.h"

#include "imgILoader.h"
#include "imgICache.h"
#include "nsWeakReference.h"
#include "nsIContentSniffer.h"
#include "nsRefPtrHashtable.h"
#include "nsExpirationTracker.h"
#include "ImageCacheKey.h"
#include "imgRequest.h"
#include "nsIProgressEventSink.h"
#include "nsIChannel.h"
#include "nsIThreadRetargetableStreamListener.h"
#include "imgIRequest.h"
#include "mozilla/net/ReferrerPolicy.h"

class imgLoader;
class imgRequestProxy;
class imgINotificationObserver;
class nsILoadGroup;
class imgCacheExpirationTracker;
class imgMemoryReporter;

namespace mozilla {
namespace image {}  // namespace image
}  // namespace mozilla

class imgCacheEntry {
 public:
  static uint32_t SecondsFromPRTime(PRTime prTime);

  imgCacheEntry(imgLoader* loader, imgRequest* request,
                bool aForcePrincipalCheck);
  ~imgCacheEntry();

  nsrefcnt AddRef() {
    MOZ_ASSERT(int32_t(mRefCnt) >= 0, "illegal refcnt");
    NS_ASSERT_OWNINGTHREAD(imgCacheEntry);
    ++mRefCnt;
    NS_LOG_ADDREF(this, mRefCnt, "imgCacheEntry", sizeof(*this));
    return mRefCnt;
  }

  nsrefcnt Release() {
    MOZ_ASSERT(0 != mRefCnt, "dup release");
    NS_ASSERT_OWNINGTHREAD(imgCacheEntry);
    --mRefCnt;
    NS_LOG_RELEASE(this, mRefCnt, "imgCacheEntry");
    if (mRefCnt == 0) {
      mRefCnt = 1; /* stabilize */
      delete this;
      return 0;
    }
    return mRefCnt;
  }

  uint32_t GetDataSize() const { return mDataSize; }
  void SetDataSize(uint32_t aDataSize) {
    int32_t oldsize = mDataSize;
    mDataSize = aDataSize;
    UpdateCache(mDataSize - oldsize);
  }

  int32_t GetTouchedTime() const { return mTouchedTime; }
  void SetTouchedTime(int32_t time) {
    mTouchedTime = time;
    Touch(/* updateTime = */ false);
  }

  uint32_t GetLoadTime() const { return mLoadTime; }

  void UpdateLoadTime();

  int32_t GetExpiryTime() const { return mExpiryTime; }
  void SetExpiryTime(int32_t aExpiryTime) {
    mExpiryTime = aExpiryTime;
    Touch();
  }

  bool GetMustValidate() const { return mMustValidate; }
  void SetMustValidate(bool aValidate) {
    mMustValidate = aValidate;
    Touch();
  }

  already_AddRefed<imgRequest> GetRequest() const {
    RefPtr<imgRequest> req = mRequest;
    return req.forget();
  }

  bool Evicted() const { return mEvicted; }

  nsExpirationState* GetExpirationState() { return &mExpirationState; }

  bool HasNoProxies() const { return mHasNoProxies; }

  bool ForcePrincipalCheck() const { return mForcePrincipalCheck; }

  imgLoader* Loader() const { return mLoader; }

 private:  // methods
  friend class imgLoader;
  friend class imgCacheQueue;
  void Touch(bool updateTime = true);
  void UpdateCache(int32_t diff = 0);
  void SetEvicted(bool evict) { mEvicted = evict; }
  void SetHasNoProxies(bool hasNoProxies);

  // Private, unimplemented copy constructor.
  imgCacheEntry(const imgCacheEntry&);

 private:  // data
  nsAutoRefCnt mRefCnt;
  NS_DECL_OWNINGTHREAD

  imgLoader* mLoader;
  RefPtr<imgRequest> mRequest;
  uint32_t mDataSize;
  int32_t mTouchedTime;
  uint32_t mLoadTime;
  int32_t mExpiryTime;
  nsExpirationState mExpirationState;
  bool mMustValidate : 1;
  bool mEvicted : 1;
  bool mHasNoProxies : 1;
  bool mForcePrincipalCheck : 1;
};

#include <vector>

#define NS_IMGLOADER_CID                             \
  { /* c1354898-e3fe-4602-88a7-c4520c21cb4e */       \
    0xc1354898, 0xe3fe, 0x4602, {                    \
      0x88, 0xa7, 0xc4, 0x52, 0x0c, 0x21, 0xcb, 0x4e \
    }                                                \
  }

class imgCacheQueue {
 public:
  imgCacheQueue();
  void Remove(imgCacheEntry*);
  void Push(imgCacheEntry*);
  void MarkDirty();
  bool IsDirty();
  already_AddRefed<imgCacheEntry> Pop();
  void Refresh();
  uint32_t GetSize() const;
  void UpdateSize(int32_t diff);
  uint32_t GetNumElements() const;
  bool Contains(imgCacheEntry* aEntry) const;
  typedef nsTArray<RefPtr<imgCacheEntry>> queueContainer;
  typedef queueContainer::iterator iterator;
  typedef queueContainer::const_iterator const_iterator;

  iterator begin();
  const_iterator begin() const;
  iterator end();
  const_iterator end() const;

 private:
  queueContainer mQueue;
  bool mDirty;
  uint32_t mSize;
};

enum class AcceptedMimeTypes : uint8_t {
  IMAGES,
  IMAGES_AND_DOCUMENTS,
};

class imgLoader final : public imgILoader,
                        public nsIContentSniffer,
                        public imgICache,
                        public nsSupportsWeakReference,
                        public nsIObserver {
  virtual ~imgLoader();

 public:
  typedef mozilla::image::ImageCacheKey ImageCacheKey;
  typedef nsRefPtrHashtable<nsGenericHashKey<ImageCacheKey>, imgCacheEntry>
      imgCacheTable;
  typedef nsTHashtable<nsPtrHashKey<imgRequest>> imgSet;
  typedef mozilla::net::ReferrerPolicy ReferrerPolicy;
  typedef mozilla::Mutex Mutex;

  NS_DECL_ISUPPORTS
  NS_DECL_IMGILOADER
  NS_DECL_NSICONTENTSNIFFER
  NS_DECL_IMGICACHE
  NS_DECL_NSIOBSERVER

  /**
   * Get the normal image loader instance that is used by gecko code, creating
   * it if necessary.
   */
  static imgLoader* NormalLoader();

  /**
   * Get the Private Browsing image loader instance that is used by gecko code,
   * creating it if necessary.
   */
  static imgLoader* PrivateBrowsingLoader();

  /**
   * Gecko code should use NormalLoader() or PrivateBrowsingLoader() to get the
   * appropriate image loader.
   *
   * This constructor is public because the XPCOM module code that creates
   * instances of "@mozilla.org/image/loader;1" / "@mozilla.org/image/cache;1"
   * for nsIComponentManager.createInstance()/nsIServiceManager.getService()
   * calls (now only made by add-ons) needs access to it.
   *
   * XXX We would like to get rid of the nsIServiceManager.getService (and
   * nsIComponentManager.createInstance) method of creating imgLoader objects,
   * but there are add-ons that are still using it.  These add-ons don't
   * actually do anything useful with the loaders that they create since nobody
   * who creates an imgLoader using this method actually QIs to imgILoader and
   * loads images.  They all just QI to imgICache and either call clearCache()
   * or findEntryProperties().  Since they're doing this on an imgLoader that
   * has never loaded images, these calls are useless.  It seems likely that
   * the code that is doing this is just legacy code left over from a time when
   * there was only one imgLoader instance for the entire process.  (Nowadays
   * the correct method to get an imgILoader/imgICache is to call
   * imgITools::getImgCacheForDocument/imgITools::getImgLoaderForDocument.)
   * All the same, even though what these add-ons are doing is a no-op,
   * removing the nsIServiceManager.getService method of creating/getting an
   * imgLoader objects would cause an exception in these add-ons that could
   * break things.
   */
  imgLoader();
  nsresult Init();

  MOZ_MUST_USE nsresult
  LoadImage(nsIURI* aURI, nsIURI* aInitialDocumentURI, nsIURI* aReferrerURI,
            ReferrerPolicy aReferrerPolicy, nsIPrincipal* aLoadingPrincipal,
            uint64_t aRequestContextID, nsILoadGroup* aLoadGroup,
            imgINotificationObserver* aObserver, nsINode* aContext,
            nsIDocument* aLoadingDocument, nsLoadFlags aLoadFlags,
            nsISupports* aCacheKey, nsContentPolicyType aContentPolicyType,
            const nsAString& initiatorType, bool aUseUrgentStartForChannel,
            imgRequestProxy** _retval);

  MOZ_MUST_USE nsresult
  LoadImageWithChannel(nsIChannel* channel, imgINotificationObserver* aObserver,
                       nsISupports* aCX, nsIStreamListener** listener,
                       imgRequestProxy** _retval);

  static nsresult GetMimeTypeFromContent(const char* aContents,
                                         uint32_t aLength,
                                         nsACString& aContentType);

  /**
   * Returns true if the given mime type may be interpreted as an image.
   *
   * Some MIME types may be interpreted as both images and documents. (At the
   * moment only "image/svg+xml" falls into this category, but there may be more
   * in the future.) Callers which want this function to return true for such
   * MIME types should pass AcceptedMimeTypes::IMAGES_AND_DOCUMENTS for
   * @aAccept.
   *
   * @param aMimeType The MIME type to evaluate.
   * @param aAcceptedMimeTypes Which kinds of MIME types to treat as images.
   */
  static bool SupportImageWithMimeType(
      const char* aMimeType,
      AcceptedMimeTypes aAccept = AcceptedMimeTypes::IMAGES);

  static void GlobalInit();  // for use by the factory
  static void Shutdown();    // for use by the factory
  static void ShutdownMemoryReporter();

  nsresult ClearChromeImageCache();
  nsresult ClearImageCache();
  void MinimizeCaches();

  nsresult InitCache();

  bool RemoveFromCache(const ImageCacheKey& aKey);

  // Enumeration describing if a given entry is in the cache queue or not.
  // There are some cases we know the entry is definitely not in the queue.
  enum class QueueState { MaybeExists, AlreadyRemoved };

  bool RemoveFromCache(imgCacheEntry* entry,
                       QueueState aQueueState = QueueState::MaybeExists);

  bool PutIntoCache(const ImageCacheKey& aKey, imgCacheEntry* aEntry);

  void AddToUncachedImages(imgRequest* aRequest);
  void RemoveFromUncachedImages(imgRequest* aRequest);

  // Returns true if we should prefer evicting cache entry |two| over cache
  // entry |one|.
  // This mixes units in the worst way, but provides reasonable results.
  inline static bool CompareCacheEntries(const RefPtr<imgCacheEntry>& one,
                                         const RefPtr<imgCacheEntry>& two) {
    if (!one) {
      return false;
    }
    if (!two) {
      return true;
    }

    const double sizeweight = 1.0 - sCacheTimeWeight;

    // We want large, old images to be evicted first (depending on their
    // relative weights). Since a larger time is actually newer, we subtract
    // time's weight, so an older image has a larger weight.
    double oneweight = double(one->GetDataSize()) * sizeweight -
                       double(one->GetTouchedTime()) * sCacheTimeWeight;
    double twoweight = double(two->GetDataSize()) * sizeweight -
                       double(two->GetTouchedTime()) * sCacheTimeWeight;

    return oneweight < twoweight;
  }

  void VerifyCacheSizes();

  // The image loader maintains a hash table of all imgCacheEntries. However,
  // only some of them will be evicted from the cache: those who have no
  // imgRequestProxies watching their imgRequests.
  //
  // Once an imgRequest has no imgRequestProxies, it should notify us by
  // calling HasNoObservers(), and null out its cache entry pointer.
  //
  // Upon having a proxy start observing again, it should notify us by calling
  // HasObservers(). The request's cache entry will be re-set before this
  // happens, by calling imgRequest::SetCacheEntry() when an entry with no
  // observers is re-requested.
  bool SetHasNoProxies(imgRequest* aRequest, imgCacheEntry* aEntry);
  bool SetHasProxies(imgRequest* aRequest);

 private:  // methods
  static already_AddRefed<imgLoader> CreateImageLoader();

  bool ValidateEntry(imgCacheEntry* aEntry, nsIURI* aKey,
                     nsIURI* aInitialDocumentURI, nsIURI* aReferrerURI,
                     ReferrerPolicy aReferrerPolicy, nsILoadGroup* aLoadGroup,
                     imgINotificationObserver* aObserver, nsISupports* aCX,
                     nsIDocument* aLoadingDocument, nsLoadFlags aLoadFlags,
                     nsContentPolicyType aContentPolicyType,
                     bool aCanMakeNewChannel, bool* aNewChannelCreated,
                     imgRequestProxy** aProxyRequest,
                     nsIPrincipal* aLoadingPrincipal, int32_t aCORSMode);

  bool ValidateRequestWithNewChannel(
      imgRequest* request, nsIURI* aURI, nsIURI* aInitialDocumentURI,
      nsIURI* aReferrerURI, ReferrerPolicy aReferrerPolicy,
      nsILoadGroup* aLoadGroup, imgINotificationObserver* aObserver,
      nsISupports* aCX, nsIDocument* aLoadingDocument, nsLoadFlags aLoadFlags,
      nsContentPolicyType aContentPolicyType, imgRequestProxy** aProxyRequest,
      nsIPrincipal* aLoadingPrincipal, int32_t aCORSMode,
      bool* aNewChannelCreated);

  nsresult CreateNewProxyForRequest(imgRequest* aRequest,
                                    nsILoadGroup* aLoadGroup,
                                    nsIDocument* aLoadingDocument,
                                    imgINotificationObserver* aObserver,
                                    nsLoadFlags aLoadFlags,
                                    imgRequestProxy** _retval);

  void ReadAcceptHeaderPref();

  nsresult EvictEntries(imgCacheTable& aCacheToClear);
  nsresult EvictEntries(imgCacheQueue& aQueueToClear);

  imgCacheTable& GetCache(bool aForChrome);
  imgCacheTable& GetCache(const ImageCacheKey& aKey);
  imgCacheQueue& GetCacheQueue(bool aForChrome);
  imgCacheQueue& GetCacheQueue(const ImageCacheKey& aKey);
  void CacheEntriesChanged(bool aForChrome, int32_t aSizeDiff = 0);
  void CheckCacheLimits(imgCacheTable& cache, imgCacheQueue& queue);

 private:  // data
  friend class imgCacheEntry;
  friend class imgMemoryReporter;

  imgCacheTable mCache;
  imgCacheQueue mCacheQueue;

  imgCacheTable mChromeCache;
  imgCacheQueue mChromeCacheQueue;

  // Hash set of every imgRequest for this loader that isn't in mCache or
  // mChromeCache. The union over all imgLoader's of mCache, mChromeCache, and
  // mUncachedImages should be every imgRequest that is alive. These are weak
  // pointers so we rely on the imgRequest destructor to remove itself.
  imgSet mUncachedImages;
  // The imgRequest can have refs to them held on non-main thread, so we need
  // a mutex because we modify the uncached images set from the imgRequest
  // destructor.
  Mutex mUncachedImagesMutex;

  static double sCacheTimeWeight;
  static uint32_t sCacheMaxSize;
  static imgMemoryReporter* sMemReporter;

  nsCString mAcceptHeader;

  mozilla::UniquePtr<imgCacheExpirationTracker> mCacheTracker;
  bool mRespectPrivacy;
};

/**
 * proxy stream listener class used to handle multipart/x-mixed-replace
 */

#include "nsCOMPtr.h"
#include "nsIStreamListener.h"
#include "nsIThreadRetargetableStreamListener.h"

class ProxyListener : public nsIStreamListener,
                      public nsIThreadRetargetableStreamListener {
 public:
  explicit ProxyListener(nsIStreamListener* dest);

  /* additional members */
  NS_DECL_THREADSAFE_ISUPPORTS
  NS_DECL_NSISTREAMLISTENER
  NS_DECL_NSITHREADRETARGETABLESTREAMLISTENER
  NS_DECL_NSIREQUESTOBSERVER

 private:
  virtual ~ProxyListener();

  nsCOMPtr<nsIStreamListener> mDestListener;
};

/**
 * A class that implements nsIProgressEventSink and forwards all calls to it to
 * the original notification callbacks of the channel. Also implements
 * nsIInterfaceRequestor and gives out itself for nsIProgressEventSink calls,
 * and forwards everything else to the channel's notification callbacks.
 */
class nsProgressNotificationProxy final : public nsIProgressEventSink,
                                          public nsIChannelEventSink,
                                          public nsIInterfaceRequestor {
 public:
  nsProgressNotificationProxy(nsIChannel* channel, imgIRequest* proxy)
      : mImageRequest(proxy) {
    channel->GetNotificationCallbacks(getter_AddRefs(mOriginalCallbacks));
  }

  NS_DECL_ISUPPORTS
  NS_DECL_NSIPROGRESSEVENTSINK
  NS_DECL_NSICHANNELEVENTSINK
  NS_DECL_NSIINTERFACEREQUESTOR
 private:
  ~nsProgressNotificationProxy() {}

  nsCOMPtr<nsIInterfaceRequestor> mOriginalCallbacks;
  nsCOMPtr<nsIRequest> mImageRequest;
};

/**
 * validate checker
 */

#include "nsCOMArray.h"

class imgCacheValidator : public nsIStreamListener,
                          public nsIThreadRetargetableStreamListener,
                          public nsIChannelEventSink,
                          public nsIInterfaceRequestor,
                          public nsIAsyncVerifyRedirectCallback {
 public:
  imgCacheValidator(nsProgressNotificationProxy* progress, imgLoader* loader,
                    imgRequest* aRequest, nsISupports* aContext,
                    bool forcePrincipalCheckForCacheEntry);

  void AddProxy(imgRequestProxy* aProxy);
  void RemoveProxy(imgRequestProxy* aProxy);

  NS_DECL_THREADSAFE_ISUPPORTS
  NS_DECL_NSITHREADRETARGETABLESTREAMLISTENER
  NS_DECL_NSISTREAMLISTENER
  NS_DECL_NSIREQUESTOBSERVER
  NS_DECL_NSICHANNELEVENTSINK
  NS_DECL_NSIINTERFACEREQUESTOR
  NS_DECL_NSIASYNCVERIFYREDIRECTCALLBACK

 private:
  void UpdateProxies(bool aCancelRequest, bool aSyncNotify);
  virtual ~imgCacheValidator();

  nsCOMPtr<nsIStreamListener> mDestListener;
  RefPtr<nsProgressNotificationProxy> mProgressProxy;
  nsCOMPtr<nsIAsyncVerifyRedirectCallback> mRedirectCallback;
  nsCOMPtr<nsIChannel> mRedirectChannel;

  RefPtr<imgRequest> mRequest;
  AutoTArray<RefPtr<imgRequestProxy>, 4> mProxies;

  RefPtr<imgRequest> mNewRequest;
  RefPtr<imgCacheEntry> mNewEntry;

  nsCOMPtr<nsISupports> mContext;

  imgLoader* mImgLoader;

  bool mHadInsecureRedirect;
};

#endif  // mozilla_image_imgLoader_h