The Tor Browser: xpcom/glue/nsCycleCollectionNoteChild.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 // This header will be included by headers that define refpointer and array classes

     7 // in order to specialize CC helpers such as ImplCycleCollectionTraverse for them.

     9 #ifndef nsCycleCollectionNoteChild_h__

    10 #define nsCycleCollectionNoteChild_h__

    12 #include "nsCycleCollectionTraversalCallback.h"

    13 #include "mozilla/Likely.h"

    14 #include "mozilla/TypeTraits.h"

    16 enum {

    17   CycleCollectionEdgeNameArrayFlag = 1

    18 };

    20 // Just a helper for appending "[i]". Didn't want to pull in string headers here.

    21 void

    22 CycleCollectionNoteEdgeNameImpl(nsCycleCollectionTraversalCallback& aCallback,

    23                                 const char* aName,

    24                                 uint32_t aFlags = 0);

    26 // Should be inlined so that in the no-debug-info case this is just a simple if().

    27 MOZ_ALWAYS_INLINE void

    28 CycleCollectionNoteEdgeName(nsCycleCollectionTraversalCallback& aCallback,

    29                             const char* aName,

    30                             uint32_t aFlags = 0)

    31 {

    32   if (MOZ_UNLIKELY(aCallback.WantDebugInfo())) {

    33     CycleCollectionNoteEdgeNameImpl(aCallback, aName, aFlags);

    34   }

    35 }

    37 #define NS_CYCLE_COLLECTION_INNERCLASS                                         \

    38         cycleCollection

    40 #define NS_CYCLE_COLLECTION_INNERNAME                                          \

    41         _cycleCollectorGlobal

    43 #define NS_CYCLE_COLLECTION_PARTICIPANT(_class)                                \

    44         _class::NS_CYCLE_COLLECTION_INNERCLASS::GetParticipant()

    46 template <typename T>

    47 nsISupports* ToSupports(T* p, typename T::NS_CYCLE_COLLECTION_INNERCLASS* dummy = 0)

    48 {

    49   return T::NS_CYCLE_COLLECTION_INNERCLASS::Upcast(p);

    50 }

    52 // The default implementation of this class template is empty, because it

    53 // should never be used: see the partial specializations below.

    54 template <typename T,

    55           bool IsXPCOM = mozilla::IsBaseOf<nsISupports, T>::value>

    56 struct CycleCollectionNoteChildImpl

    57 {

    58 };

    60 template <typename T>

    61 struct CycleCollectionNoteChildImpl<T, true>

    62 {

    63   static void Run(nsCycleCollectionTraversalCallback& aCallback, T* aChild)

    64   {

    65     aCallback.NoteXPCOMChild(ToSupports(aChild));

    66   }

    67 };

    69 template <typename T>

    70 struct CycleCollectionNoteChildImpl<T, false>

    71 {

    72   static void Run(nsCycleCollectionTraversalCallback& aCallback, T* aChild)

    73   {

    74     aCallback.NoteNativeChild(aChild, NS_CYCLE_COLLECTION_PARTICIPANT(T));

    75   }

    76 };

    78 template <typename T>

    79 inline void CycleCollectionNoteChild(nsCycleCollectionTraversalCallback& aCallback,

    80                                      T* aChild,

    81                                      const char* aName,

    82                                      uint32_t aFlags = 0)

    83 {

    84   CycleCollectionNoteEdgeName(aCallback, aName, aFlags);

    85   CycleCollectionNoteChildImpl<T>::Run(aCallback, aChild);

    86 }

    88 #endif // nsCycleCollectionNoteChild_h__

The Tor Browser / file revision

xpcom/glue/nsCycleCollectionNoteChild.h@97036ab72558

xpcom/glue/nsCycleCollectionNoteChild.h