The Tor Browser: accessible/src/base/nsAccCache.h@97036ab72558

Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

     1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

     2 /* This Source Code Form is subject to the terms of the Mozilla Public

     3  * License, v. 2.0. If a copy of the MPL was not distributed with this

     4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

     6 #ifndef _nsAccCache_H_

     7 #define _nsAccCache_H_

     9 #include "nsIAccessible.h"

    10 #include "nsRefPtrHashtable.h"

    11 #include "nsCycleCollectionParticipant.h"

    13 ////////////////////////////////////////////////////////////////////////////////

    14 // Accessible cache utils

    15 ////////////////////////////////////////////////////////////////////////////////

    17 /**

    18  * Shutdown and removes the accessible from cache.

    19  */

    20 template <class T>

    21 static PLDHashOperator

    22 ClearCacheEntry(const void* aKey, nsRefPtr<T>& aAccessible, void* aUserArg)

    23 {

    24   NS_ASSERTION(aAccessible, "Calling ClearCacheEntry with a nullptr pointer!");

    25   if (aAccessible)

    26     aAccessible->Shutdown();

    28   return PL_DHASH_REMOVE;

    29 }

    31 /**

    32  * Clear the cache and shutdown the accessibles.

    33  */

    35 static void

    36 ClearCache(mozilla::a11y::AccessibleHashtable& aCache)

    37 {

    38   aCache.Enumerate(ClearCacheEntry<mozilla::a11y::Accessible>, nullptr);

    39 }

    41 /**

    42  * Traverse the accessible cache entry for cycle collector.

    43  */

    44 template <class T>

    45 static PLDHashOperator

    46 CycleCollectorTraverseCacheEntry(const void *aKey, T *aAccessible,

    47                                  void *aUserArg)

    48 {

    49   nsCycleCollectionTraversalCallback *cb =

    50     static_cast<nsCycleCollectionTraversalCallback*>(aUserArg);

    52   NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(*cb, "accessible cache entry");

    54   nsISupports *supports = static_cast<nsIAccessible*>(aAccessible);

    55   cb->NoteXPCOMChild(supports);

    56   return PL_DHASH_NEXT;

    57 }

    59 /**

    60  * Unlink the accessible cache for the cycle collector.

    61  */

    62 inline void

    63 ImplCycleCollectionUnlink(mozilla::a11y::AccessibleHashtable& aCache)

    64 {

    65   ClearCache(aCache);

    66 }

    68 /**

    69  * Traverse the accessible cache for cycle collector.

    70  */

    71 inline void

    72 ImplCycleCollectionTraverse(nsCycleCollectionTraversalCallback& aCallback,

    73                             mozilla::a11y::AccessibleHashtable& aCache,

    74                             const char* aName,

    75                             uint32_t aFlags = 0)

    76 {

    77   aCache.EnumerateRead(CycleCollectorTraverseCacheEntry<mozilla::a11y::Accessible>,

    78                        &aCallback);

    79 }

    81 #endif

The Tor Browser / file revision

accessible/src/base/nsAccCache.h@97036ab72558

accessible/src/base/nsAccCache.h