dom/quota/StringifyUtils.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   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 "mozilla/ThreadLocal.h"
   8 #include "mozilla/dom/quota/StringifyUtils.h"
   9 #include "nsTHashSet.h"
  10
  11 namespace mozilla {
  12
  13 MOZ_THREAD_LOCAL(nsTHashSet<Stringifyable*>*)
  14 Stringifyable::sActiveStringifyableInstances;
  15
  16 #ifdef DEBUG
  17 Atomic<bool> sStringifyableTLSInitialized(false);
  18 #endif
  19
  20 void Stringifyable::Stringify(nsACString& aData) {
  21   if (IsActive()) {
  22     aData.Append("(...)"_ns);
  23     return;
  24   }
  25
  26   SetActive(true);
  27   aData.Append(kStringifyStartInstance);
  28   DoStringify(aData);
  29   aData.Append(kStringifyEndInstance);
  30   SetActive(false);
  31 }
  32
  33 /* static */ void Stringifyable::InitTLS() {
  34   if (sActiveStringifyableInstances.init()) {
  35 #ifdef DEBUG
  36     sStringifyableTLSInitialized = true;
  37 #endif
  38   }
  39 }
  40
  41 bool Stringifyable::IsActive() {
  42   MOZ_ASSERT(sStringifyableTLSInitialized);
  43   auto* set = sActiveStringifyableInstances.get();
  44   return set && set->Contains(this);
  45 }
  46
  47 void Stringifyable::SetActive(bool aIsActive) {
  48   MOZ_ASSERT(sStringifyableTLSInitialized);
  49   auto* myset = sActiveStringifyableInstances.get();
  50   if (!myset && aIsActive) {
  51     myset = new nsTHashSet<Stringifyable*>();
  52     sActiveStringifyableInstances.set(myset);
  53   }
  54   MOZ_ASSERT(myset);
  55   if (aIsActive) {
  56     myset->Insert(this);
  57   } else {
  58     myset->Remove(this);
  59     if (myset->IsEmpty()) {
  60       sActiveStringifyableInstances.set(nullptr);
  61       delete myset;
  62     }
  63   }
  64 }
  65
  66 }  // namespace mozilla