dom/quota/ScopedLogExtraInfo.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 file,
   5  * You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "ScopedLogExtraInfo.h"
   8
   9 namespace mozilla::dom::quota {
  10
  11 #ifdef QM_SCOPED_LOG_EXTRA_INFO_ENABLED
  12 MOZ_THREAD_LOCAL(const Tainted<nsCString>*)
  13 ScopedLogExtraInfo::sQueryValueTainted;
  14 MOZ_THREAD_LOCAL(const Tainted<nsCString>*)
  15 ScopedLogExtraInfo::sContextValueTainted;
  16 MOZ_THREAD_LOCAL(const Tainted<nsCString>*)
  17 ScopedLogExtraInfo::sStorageOriginValueTainted;
  18
  19 /* static */
  20 auto ScopedLogExtraInfo::FindSlot(const char* aTag) {
  21   // XXX For now, don't use a real map but just allow the known tag values.
  22
  23   if (aTag == kTagQueryTainted) {
  24     return &sQueryValueTainted;
  25   }
  26
  27   if (aTag == kTagContextTainted) {
  28     return &sContextValueTainted;
  29   }
  30
  31   if (aTag == kTagStorageOriginTainted) {
  32     return &sStorageOriginValueTainted;
  33   }
  34
  35   MOZ_CRASH("Unknown tag!");
  36 }
  37
  38 ScopedLogExtraInfo::~ScopedLogExtraInfo() {
  39   if (mTag) {
  40     MOZ_ASSERT(&mCurrentValue == FindSlot(mTag)->get(),
  41                "Bad scoping of ScopedLogExtraInfo, must not be interleaved!");
  42
  43     FindSlot(mTag)->set(mPreviousValue);
  44   }
  45 }
  46
  47 ScopedLogExtraInfo::ScopedLogExtraInfo(ScopedLogExtraInfo&& aOther) noexcept
  48     : mTag(aOther.mTag),
  49       mPreviousValue(aOther.mPreviousValue),
  50       mCurrentValue(std::move(aOther.mCurrentValue)) {
  51   aOther.mTag = nullptr;
  52   FindSlot(mTag)->set(&mCurrentValue);
  53 }
  54
  55 /* static */ ScopedLogExtraInfo::ScopedLogExtraInfoMap
  56 ScopedLogExtraInfo::GetExtraInfoMap() {
  57   // This could be done in a cheaper way, but this is never called on a hot
  58   // path, so we anticipate using a real map inside here to make use simpler for
  59   // the caller(s).
  60
  61   ScopedLogExtraInfoMap map;
  62   if (sQueryValueTainted.get()) {
  63     map.emplace(kTagQueryTainted, sQueryValueTainted.get());
  64   }
  65
  66   if (sContextValueTainted.get()) {
  67     map.emplace(kTagContextTainted, sContextValueTainted.get());
  68   }
  69
  70   if (sStorageOriginValueTainted.get()) {
  71     map.emplace(kTagStorageOriginTainted, sStorageOriginValueTainted.get());
  72   }
  73
  74   return map;
  75 }
  76
  77 /* static */ void ScopedLogExtraInfo::Initialize() {
  78   MOZ_ALWAYS_TRUE(sQueryValueTainted.init());
  79   MOZ_ALWAYS_TRUE(sContextValueTainted.init());
  80   MOZ_ALWAYS_TRUE(sStorageOriginValueTainted.init());
  81 }
  82
  83 void ScopedLogExtraInfo::AddInfo() {
  84   auto* slot = FindSlot(mTag);
  85   MOZ_ASSERT(slot);
  86   mPreviousValue = slot->get();
  87
  88   slot->set(&mCurrentValue);
  89 }
  90 #endif
  91
  92 }  // namespace mozilla::dom::quota