dom/localstorage/LSWriteOptimizer.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=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 "LSWriteOptimizer.h"
   8
   9 #include <new>
  10 #include "nsBaseHashtable.h"
  11 #include "nsTArray.h"
  12
  13 namespace mozilla::dom {
  14
  15 class LSWriteOptimizerBase::WriteInfoComparator {
  16  public:
  17   bool Equals(const WriteInfo* a, const WriteInfo* b) const {
  18     MOZ_ASSERT(a && b);
  19     return a->SerialNumber() == b->SerialNumber();
  20   }
  21
  22   bool LessThan(const WriteInfo* a, const WriteInfo* b) const {
  23     MOZ_ASSERT(a && b);
  24     return a->SerialNumber() < b->SerialNumber();
  25   }
  26 };
  27
  28 void LSWriteOptimizerBase::DeleteItem(const nsAString& aKey, int64_t aDelta) {
  29   AssertIsOnOwningThread();
  30
  31   WriteInfo* existingWriteInfo;
  32   if (mWriteInfos.Get(aKey, &existingWriteInfo) &&
  33       existingWriteInfo->GetType() == WriteInfo::InsertItem) {
  34     mWriteInfos.Remove(aKey);
  35   } else {
  36     mWriteInfos.Put(aKey, MakeUnique<DeleteItemInfo>(NextSerialNumber(), aKey));
  37   }
  38
  39   mTotalDelta += aDelta;
  40 }
  41
  42 void LSWriteOptimizerBase::Truncate(int64_t aDelta) {
  43   AssertIsOnOwningThread();
  44
  45   mWriteInfos.Clear();
  46
  47   if (!mTruncateInfo) {
  48     mTruncateInfo = MakeUnique<TruncateInfo>(NextSerialNumber());
  49   }
  50
  51   mTotalDelta += aDelta;
  52 }
  53
  54 void LSWriteOptimizerBase::GetSortedWriteInfos(
  55     nsTArray<NotNull<WriteInfo*>>& aWriteInfos) {
  56   AssertIsOnOwningThread();
  57
  58   if (mTruncateInfo) {
  59     aWriteInfos.InsertElementSorted(WrapNotNullUnchecked(mTruncateInfo.get()),
  60                                     WriteInfoComparator());
  61   }
  62
  63   for (auto iter = mWriteInfos.ConstIter(); !iter.Done(); iter.Next()) {
  64     WriteInfo* writeInfo = iter.UserData();
  65
  66     aWriteInfos.InsertElementSorted(WrapNotNull(writeInfo),
  67                                     WriteInfoComparator());
  68   }
  69 }
  70
  71 }  // namespace mozilla::dom