image/imgIRequest.idl

   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 #include "nsISupports.idl"
   8 #include "nsIRequest.idl"
   9 #include "imgIContainer.idl"
  10
  11 //interface imgIContainer;
  12 interface imgINotificationObserver;
  13 interface nsIURI;
  14 interface nsIPrincipal;
  15
  16 /**
  17  * imgIRequest interface
  18  *
  19  * @author Stuart Parmenter <stuart@mozilla.com>
  20  * @version 0.1
  21  * @see imagelib2
  22  */
  23 [scriptable, builtinclass, uuid(db0a945c-3883-424a-98d0-2ee0523b0255)]
  24 interface imgIRequest : nsIRequest
  25 {
  26   /**
  27    * the image container...
  28    * @return the image object associated with the request.
  29    * @attention NEED DOCS
  30    */
  31   readonly attribute imgIContainer image;
  32
  33   /**
  34    * Provider ID for image providers created by this image.
  35    */
  36   [infallible] readonly attribute unsigned long providerId;
  37
  38   /**
  39    * The principal for the document that loaded this image. Used when trying to
  40    * validate a CORS image load.
  41    */
  42   [infallible] readonly attribute nsIPrincipal triggeringPrincipal;
  43
  44   /**
  45    * Bits set in the return value from imageStatus
  46    * @name statusflags
  47    *
  48    * Meanings:
  49    *
  50    * STATUS_NONE: Nothing to report.
  51    *
  52    * STATUS_SIZE_AVAILABLE: We received enough image data
  53    * from the network or filesystem that we know the width
  54    * and height of the image, and have thus called SetSize()
  55    * on the container.
  56    *
  57    * STATUS_LOAD_COMPLETE: The data has been fully loaded
  58    * to memory, but not necessarily fully decoded.
  59    *
  60    * STATUS_ERROR: An error occurred loading the image.
  61    *
  62    * STATUS_FRAME_COMPLETE: The first frame has been
  63    * completely decoded.
  64    *
  65    * STATUS_DECODE_COMPLETE: The whole image has been decoded.
  66    *
  67    * STATUS_IS_ANIMATED: The image is animated.
  68    *
  69    * STATUS_HAS_TRANSPARENCY: The image is partially or completely transparent.
  70    */
  71   //@{
  72   const long STATUS_NONE             = 0x0;
  73   const long STATUS_SIZE_AVAILABLE   = 0x1;
  74   const long STATUS_LOAD_COMPLETE    = 0x2;
  75   const long STATUS_ERROR            = 0x4;
  76   const long STATUS_FRAME_COMPLETE   = 0x8;
  77   const long STATUS_DECODE_COMPLETE  = 0x10;
  78   const long STATUS_IS_ANIMATED      = 0x20;
  79   const long STATUS_HAS_TRANSPARENCY = 0x40;
  80   //@}
  81
  82   /**
  83    * Status flags of the STATUS_* variety.
  84    */
  85   readonly attribute unsigned long imageStatus;
  86
  87   /*
  88    * Actual error code that generated a STATUS_ERROR imageStatus
  89    * (see xpcom/base/ErrorList.h)
  90    */
  91   [noscript] readonly attribute nsresult imageErrorCode;
  92
  93   /**
  94    * The URI the image load was started with.  Note that this might not be the
  95    * actual URI for the image (e.g. if HTTP redirects happened during the
  96    * load).
  97    */
  98   [infallible] readonly attribute nsIURI URI;
  99
 100   /**
 101    * The URI of the resource we ended up loading after all redirects, etc.
 102    */
 103   readonly attribute nsIURI finalURI;
 104
 105   readonly attribute imgINotificationObserver notificationObserver;
 106
 107   readonly attribute string mimeType;
 108
 109   /**
 110    * The filename that should be used when saving the image. This is determined
 111    * from the Content-Disposition, if present, or the uri of the image. This
 112    * filename should be validated using nsIMIMEService::GetValidFilenameForSaving
 113    * before creating the file.
 114    */
 115   readonly attribute ACString fileName;
 116
 117   /**
 118    * Clone this request; the returned request will have aObserver as the
 119    * observer.  aObserver will be notified synchronously (before the clone()
 120    * call returns) with all the notifications that have already been dispatched
 121    * for this image load.
 122    */
 123   imgIRequest clone(in imgINotificationObserver aObserver);
 124
 125   /**
 126    * The principal gotten from the channel the image was loaded from.
 127    */
 128   readonly attribute nsIPrincipal imagePrincipal;
 129
 130   /**
 131    * true if the loading of the image required cross-origin redirects.
 132    */
 133   readonly attribute bool hadCrossOriginRedirects;
 134
 135   /**
 136    * Whether the request is multipart (ie, multipart/x-mixed-replace)
 137    */
 138   readonly attribute bool multipart;
 139
 140   /**
 141    * The CORS mode that this image was loaded with (a mozilla::CORSMode).
 142    */
 143   readonly attribute long CORSMode;
 144
 145   /**
 146    * Cancels this request as in nsIRequest::Cancel(); further, also nulls out
 147    * decoderObserver so it gets no further notifications from us.
 148    *
 149    * NOTE: You should not use this in any new code; instead, use cancel(). Note
 150    * that cancel() is asynchronous, which means that some time after you call
 151    * it, the listener/observer will get an OnStopRequest(). This means that, if
 152    * you're the observer, you can't call cancel() from your destructor.
 153    */
 154   void cancelAndForgetObserver(in nsresult aStatus);
 155
 156   /**
 157    * Requests a synchronous decode for the image.
 158    *
 159    * imgIContainer has a startDecoding() method, but callers may want to request
 160    * a decode before the container has necessarily been instantiated. Calling
 161    * startDecoding() on the imgIRequest simply forwards along the request if the
 162    * container already exists, or calls it once the container becomes available
 163    * if it does not yet exist.
 164    */
 165   void startDecoding(in uint32_t aFlags);
 166
 167   /**
 168    * Exactly like startDecoding above except returns whether the current frame
 169    * of the image is complete or not.
 170    *
 171    * @param aFlags Flags of the FLAG_* variety. Only FLAG_ASYNC_NOTIFY
 172    *               is accepted; all others are ignored.
 173    */
 174   [noscript, notxpcom] boolean startDecodingWithResult(in uint32_t aFlags);
 175
 176   /**
 177    * This method triggers decoding for an image, but unlike startDecoding() it
 178    * enables the caller to provide more detailed information about the decode
 179    * request.
 180    *
 181    * @param aFlags Flags of the FLAG_* variety.
 182    * @return DECODE_SURFACE_AVAILABLE if is a surface that satisfies the
 183    *         request and it is fully decoded.
 184    *         DECODE_REQUESTED if we requested a decode.
 185    *         DECODE_REQUEST_FAILED if we failed to request a decode. This means
 186    *         that either there is an error in the image or we cannot allocate a
 187    *         surface that big.
 188    */
 189   [noscript, notxpcom] imgIContainer_DecodeResult requestDecodeWithResult(in uint32_t aFlags);
 190 /*%{C++
 191   DecodeResult RequestDecodeWithResult(uint32_t aFlags);
 192 %}*/
 193
 194   /**
 195    * Returns true if there is a image and the image has a frame and the frame
 196    * currently has a least 1 decoded pixel. Only valid for raster images.
 197    */
 198   [noscript, notxpcom] boolean hasDecodedPixels();
 199
 200   /**
 201    * Locks an image. If the image does not exist yet, locks it once it becomes
 202    * available. The lock persists for the lifetime of the imgIRequest (until
 203    * unlockImage is called) even if the underlying image changes.
 204    *
 205    * If you don't call unlockImage() by the time this imgIRequest goes away, it
 206    * will be called for you automatically.
 207    *
 208    * @see imgIContainer::lockImage for documentation of the underlying call.
 209    */
 210   void lockImage();
 211
 212   /**
 213    * Unlocks an image.
 214    *
 215    * @see imgIContainer::unlockImage for documentation of the underlying call.
 216    */
 217   void unlockImage();
 218
 219   /**
 220    * If this image is unlocked, discard the image's decoded data.  If the image
 221    * is locked or is already discarded, do nothing.
 222    */
 223   void requestDiscard();
 224
 225   /**
 226    * If this request is for an animated image, the method creates a new
 227    * request which contains the current frame of the image.
 228    * Otherwise returns the same request.
 229    */
 230   imgIRequest getStaticRequest();
 231
 232   /**
 233    * Requests that the image animate (if it has an animation).
 234    *
 235    * @see Image::IncrementAnimationConsumers for documentation of the
 236    * underlying call.
 237    */
 238   void incrementAnimationConsumers();
 239
 240   /**
 241    * Tell the image it can forget about a request that the image animate.
 242    *
 243    * @see Image::DecrementAnimationConsumers for documentation of the
 244    * underlying call.
 245    */
 246   void decrementAnimationConsumers();
 247
 248   /**
 249    * Request loading priority boost to requested category, each category
 250    * of request increases priority only one time.
 251    *
 252    * CATEGORY_FRAME_INIT: increase priority when the imgRequest is associated
 253    * with an nsImageFrame.
 254    *
 255    * CATEGORY_FRAME_STYLE: increase priority when the imgRequest is for a CSS
 256    * background-image, list-style-image, etc. on a ComputedStyle, and a frame
 257    * has been assigned this ComputedStyle.
 258    *
 259    * CATEGORY_SIZE_QUERY: increase priority when size decoding is necessary to
 260    * determine the layout size of an associated nsImageFrame.
 261    *
 262    * CATEGORY_DISPLAY: increase priority when the image is about to be displayed
 263    * in the viewport.
 264    */
 265   const uint32_t CATEGORY_FRAME_INIT  = 1 << 0;
 266   const uint32_t CATEGORY_FRAME_STYLE = 1 << 1;
 267   const uint32_t CATEGORY_SIZE_QUERY  = 1 << 2;
 268   const uint32_t CATEGORY_DISPLAY     = 1 << 3;
 269   void boostPriority(in uint32_t aCategory);
 270 };