image/ImageCacheKey.h
author Steve Fink <sfink@mozilla.com>
Fri, 14 Dec 2018 14:41:58 -0800
changeset 458985 f0e97add682c71d36dbe895efad729307638f14f
parent 452446 f0a91d36587266d7454a450c6044d573664fbed5
child 460581 045d790ca417fc6e827b57eef8ec5aea2beef81a
permissions -rw-r--r--
Bug 1500247 - Fix bug in handling MOZ_INHERIT_ATTRIBUTE_FROM_TEMPLATE_PARAM for GC ptrdness, r=jonco

/* -*- 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/. */

/**
 * ImageCacheKey is the key type for the image cache (see imgLoader.h).
 */

#ifndef mozilla_image_src_ImageCacheKey_h
#define mozilla_image_src_ImageCacheKey_h

#include "mozilla/BasePrincipal.h"
#include "mozilla/Maybe.h"
#include "mozilla/RefPtr.h"
#include "PLDHashTable.h"

class nsIURI;

namespace mozilla {
namespace image {

/**
 * An ImageLib cache entry key.
 *
 * We key the cache on the initial URI (before any redirects), with some
 * canonicalization applied. See ComputeHash() for the details.
 * Controlled documents do not share their cache entries with
 * non-controlled documents, or other controlled documents.
 */
class ImageCacheKey final {
 public:
  ImageCacheKey(nsIURI* aURI, const OriginAttributes& aAttrs,
                dom::Document* aDocument, nsresult& aRv);

  ImageCacheKey(const ImageCacheKey& aOther);
  ImageCacheKey(ImageCacheKey&& aOther);

  bool operator==(const ImageCacheKey& aOther) const;
  PLDHashNumber Hash() const { return mHash; }

  /// A weak pointer to the URI.
  nsIURI* URI() const { return mURI; }

  const OriginAttributes& OriginAttributesRef() const {
    return mOriginAttributes;
  }

  /// Is this cache entry for a chrome image?
  bool IsChrome() const { return mIsChrome; }

  /// A token indicating which service worker controlled document this entry
  /// belongs to, if any.
  void* ControlledDocument() const { return mControlledDocument; }

 private:
  bool SchemeIs(const char* aScheme);

  // For ServiceWorker and for anti-tracking we need to use the document as
  // token for the key. All those exceptions are handled by this method.
  static void* GetSpecialCaseDocumentToken(dom::Document* aDocument,
                                           nsIURI* aURI);

  nsCOMPtr<nsIURI> mURI;
  Maybe<uint64_t> mBlobSerial;
  nsCString mBlobRef;
  OriginAttributes mOriginAttributes;
  void* mControlledDocument;
  PLDHashNumber mHash;
  bool mIsChrome;
};

}  // namespace image
}  // namespace mozilla

#endif  // mozilla_image_src_ImageCacheKey_h