image/imgRequestProxy.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
   2  *
   3  * This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef mozilla_image_imgRequestProxy_h
   8 #define mozilla_image_imgRequestProxy_h
   9
  10 #include "imgIRequest.h"
  11 #include "nsISecurityInfoProvider.h"
  12
  13 #include "nsILoadGroup.h"
  14 #include "nsISupportsPriority.h"
  15 #include "nsITimedChannel.h"
  16 #include "nsCOMPtr.h"
  17 #include "nsThreadUtils.h"
  18 #include "mozilla/TimeStamp.h"
  19 #include "mozilla/UniquePtr.h"
  20 #include "mozilla/gfx/Rect.h"
  21
  22 #include "imgRequest.h"
  23 #include "IProgressObserver.h"
  24
  25 #define NS_IMGREQUESTPROXY_CID \
  26 { /* 20557898-1dd2-11b2-8f65-9c462ee2bc95 */         \
  27      0x20557898,                                     \
  28      0x1dd2,                                         \
  29      0x11b2,                                         \
  30     {0x8f, 0x65, 0x9c, 0x46, 0x2e, 0xe2, 0xbc, 0x95} \
  31 }
  32
  33 class imgINotificationObserver;
  34 class imgStatusNotifyRunnable;
  35 class ProxyBehaviour;
  36
  37 namespace mozilla {
  38 namespace image {
  39 class Image;
  40 class ImageURL;
  41 class ProgressTracker;
  42 } // namespace image
  43 } // namespace mozilla
  44
  45 class imgRequestProxy : public imgIRequest,
  46                         public mozilla::image::IProgressObserver,
  47                         public nsISupportsPriority,
  48                         public nsISecurityInfoProvider,
  49                         public nsITimedChannel
  50 {
  51 protected:
  52   virtual ~imgRequestProxy();
  53
  54 public:
  55   typedef mozilla::image::Image Image;
  56   typedef mozilla::image::ImageURL ImageURL;
  57   typedef mozilla::image::ProgressTracker ProgressTracker;
  58
  59   MOZ_DECLARE_REFCOUNTED_TYPENAME(imgRequestProxy)
  60   NS_DECL_ISUPPORTS
  61   NS_DECL_IMGIREQUEST
  62   NS_DECL_NSIREQUEST
  63   NS_DECL_NSISUPPORTSPRIORITY
  64   NS_DECL_NSISECURITYINFOPROVIDER
  65   // nsITimedChannel declared below
  66
  67   imgRequestProxy();
  68
  69   // Callers to Init or ChangeOwner are required to call NotifyListener after
  70   // (although not immediately after) doing so.
  71   nsresult Init(imgRequest* aOwner,
  72                 nsILoadGroup* aLoadGroup,
  73                 ImageURL* aURI,
  74                 imgINotificationObserver* aObserver);
  75
  76   nsresult ChangeOwner(imgRequest* aNewOwner); // this will change mOwner.
  77                                                // Do not call this if the
  78                                                // previous owner has already
  79                                                // sent notifications out!
  80
  81   void AddToLoadGroup();
  82   void RemoveFromLoadGroup(bool releaseLoadGroup);
  83
  84   inline bool HasObserver() const {
  85     return mListener != nullptr;
  86   }
  87
  88   // Asynchronously notify this proxy's listener of the current state of the
  89   // image, and, if we have an imgRequest mOwner, any status changes that
  90   // happen between the time this function is called and the time the
  91   // notification is scheduled.
  92   void NotifyListener();
  93
  94   // Synchronously notify this proxy's listener of the current state of the
  95   // image. Only use this function if you are currently servicing an
  96   // asynchronously-called function.
  97   void SyncNotifyListener();
  98
  99   // imgINotificationObserver methods:
 100   virtual void Notify(int32_t aType,
 101                       const mozilla::gfx::IntRect* aRect = nullptr) override;
 102   virtual void OnLoadComplete(bool aLastPart) override;
 103
 104   // imgIOnloadBlocker methods:
 105   virtual void BlockOnload() override;
 106   virtual void UnblockOnload() override;
 107
 108   // Other, internal-only methods:
 109   virtual void SetHasImage() override;
 110
 111   // Whether we want notifications from ProgressTracker to be deferred until
 112   // an event it has scheduled has been fired.
 113   virtual bool NotificationsDeferred() const override
 114   {
 115     return mDeferNotifications;
 116   }
 117   virtual void SetNotificationsDeferred(bool aDeferNotifications) override
 118   {
 119     mDeferNotifications = aDeferNotifications;
 120   }
 121
 122   // Removes all animation consumers that were created with
 123   // IncrementAnimationConsumers. This is necessary since we need
 124   // to do it before the proxy itself is destroyed. See
 125   // imgRequest::RemoveProxy
 126   void ClearAnimationConsumers();
 127
 128   virtual nsresult Clone(imgINotificationObserver* aObserver,
 129                          imgRequestProxy** aClone);
 130   nsresult GetStaticRequest(imgRequestProxy** aReturn);
 131
 132   nsresult GetURI(ImageURL** aURI);
 133
 134 protected:
 135   friend class mozilla::image::ProgressTracker;
 136   friend class imgStatusNotifyRunnable;
 137
 138   class imgCancelRunnable;
 139   friend class imgCancelRunnable;
 140
 141   class imgCancelRunnable : public nsRunnable
 142   {
 143     public:
 144       imgCancelRunnable(imgRequestProxy* owner, nsresult status)
 145         : mOwner(owner), mStatus(status)
 146       { }
 147
 148       NS_IMETHOD Run() override {
 149         mOwner->DoCancel(mStatus);
 150         return NS_OK;
 151       }
 152
 153     private:
 154       RefPtr<imgRequestProxy> mOwner;
 155       nsresult mStatus;
 156   };
 157
 158   /* Finish up canceling ourselves */
 159   void DoCancel(nsresult status);
 160
 161   /* Do the proper refcount management to null out mListener */
 162   void NullOutListener();
 163
 164   void DoRemoveFromLoadGroup() {
 165     RemoveFromLoadGroup(true);
 166   }
 167
 168   // Return the ProgressTracker associated with mOwner and/or mImage. It may
 169   // live either on mOwner or mImage, depending on whether
 170   //   (a) we have an mOwner at all
 171   //   (b) whether mOwner has instantiated its image yet
 172   already_AddRefed<ProgressTracker> GetProgressTracker() const;
 173
 174   nsITimedChannel* TimedChannel()
 175   {
 176     if (!GetOwner()) {
 177       return nullptr;
 178     }
 179     return GetOwner()->GetTimedChannel();
 180   }
 181
 182   already_AddRefed<Image> GetImage() const;
 183   bool HasImage() const;
 184   imgRequest* GetOwner() const;
 185
 186   nsresult PerformClone(imgINotificationObserver* aObserver,
 187                         imgRequestProxy* (aAllocFn)(imgRequestProxy*),
 188                         imgRequestProxy** aClone);
 189
 190 public:
 191   NS_FORWARD_SAFE_NSITIMEDCHANNEL(TimedChannel())
 192
 193 protected:
 194   mozilla::UniquePtr<ProxyBehaviour> mBehaviour;
 195
 196 private:
 197   friend class imgCacheValidator;
 198   friend imgRequestProxy* NewStaticProxy(imgRequestProxy* aThis);
 199
 200   // The URI of our request.
 201   RefPtr<ImageURL> mURI;
 202
 203   // mListener is only promised to be a weak ref (see imgILoader.idl),
 204   // but we actually keep a strong ref to it until we've seen our
 205   // first OnStopRequest.
 206   imgINotificationObserver* MOZ_UNSAFE_REF("Observers must call Cancel() or "
 207                                            "CancelAndForgetObserver() before "
 208                                            "they are destroyed") mListener;
 209
 210   nsCOMPtr<nsILoadGroup> mLoadGroup;
 211
 212   nsLoadFlags mLoadFlags;
 213   uint32_t    mLockCount;
 214   uint32_t    mAnimationConsumers;
 215   bool mCanceled;
 216   bool mIsInLoadGroup;
 217   bool mListenerIsStrongRef;
 218   bool mDecodeRequested;
 219
 220   // Whether we want to defer our notifications by the non-virtual Observer
 221   // interfaces as image loads proceed.
 222   bool mDeferNotifications;
 223 };
 224
 225 // Used for static image proxies for which no requests are available, so
 226 // certain behaviours must be overridden to compensate.
 227 class imgRequestProxyStatic : public imgRequestProxy
 228 {
 229
 230 public:
 231   imgRequestProxyStatic(Image* aImage, nsIPrincipal* aPrincipal);
 232
 233   NS_IMETHOD GetImagePrincipal(nsIPrincipal** aPrincipal) override;
 234
 235   using imgRequestProxy::Clone;
 236
 237   virtual nsresult Clone(imgINotificationObserver* aObserver,
 238                          imgRequestProxy** aClone) override;
 239
 240 protected:
 241   friend imgRequestProxy* NewStaticProxy(imgRequestProxy*);
 242
 243   // Our principal. We have to cache it, rather than accessing the underlying
 244   // request on-demand, because static proxies don't have an underlying request.
 245   nsCOMPtr<nsIPrincipal> mPrincipal;
 246 };
 247
 248 #endif // mozilla_image_imgRequestProxy_h