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-rw-r--r--dom/localstorage/LSSnapshot.cpp1078
1 files changed, 1078 insertions, 0 deletions
diff --git a/dom/localstorage/LSSnapshot.cpp b/dom/localstorage/LSSnapshot.cpp
new file mode 100644
index 0000000000..e41a682ae4
--- /dev/null
+++ b/dom/localstorage/LSSnapshot.cpp
@@ -0,0 +1,1078 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/dom/LSSnapshot.h"
+
+// Local includes
+#include "ActorsChild.h"
+#include "LSDatabase.h"
+#include "LSWriteOptimizer.h"
+#include "LSWriteOptimizerImpl.h"
+#include "LocalStorageCommon.h"
+
+// Global includes
+#include <cstdint>
+#include <cstdlib>
+#include <new>
+#include <type_traits>
+#include <utility>
+#include "ErrorList.h"
+#include "mozilla/DebugOnly.h"
+#include "mozilla/MacroForEach.h"
+#include "mozilla/Maybe.h"
+#include "mozilla/Preferences.h"
+#include "mozilla/RefPtr.h"
+#include "mozilla/ScopeExit.h"
+#include "mozilla/StaticPrefs_dom.h"
+#include "mozilla/UniquePtr.h"
+#include "mozilla/dom/BindingDeclarations.h"
+#include "mozilla/dom/LSValue.h"
+#include "mozilla/dom/PBackgroundLSDatabase.h"
+#include "mozilla/dom/PBackgroundLSSharedTypes.h"
+#include "mozilla/dom/PBackgroundLSSnapshot.h"
+#include "nsBaseHashtable.h"
+#include "nsCOMPtr.h"
+#include "nsContentUtils.h"
+#include "nsDebug.h"
+#include "nsError.h"
+#include "nsITimer.h"
+#include "nsString.h"
+#include "nsStringFlags.h"
+#include "nsStringFwd.h"
+#include "nsTArray.h"
+#include "nsTStringRepr.h"
+#include "nscore.h"
+
+namespace mozilla::dom {
+
+/**
+ * Coalescing manipulation queue used by `LSSnapshot`. Used by `LSSnapshot` to
+ * buffer and coalesce manipulations before they are sent to the parent process,
+ * when a Snapshot Checkpoints. (This can only be done when there are no
+ * observers for other content processes.)
+ */
+class SnapshotWriteOptimizer final : public LSWriteOptimizer<LSValue> {
+ public:
+ void Enumerate(nsTArray<LSWriteInfo>& aWriteInfos);
+};
+
+void SnapshotWriteOptimizer::Enumerate(nsTArray<LSWriteInfo>& aWriteInfos) {
+ AssertIsOnOwningThread();
+
+ // The mWriteInfos hash table contains all write infos, but it keeps them in
+ // an arbitrary order, which means write infos need to be sorted before being
+ // processed.
+
+ nsTArray<NotNull<WriteInfo*>> writeInfos;
+ GetSortedWriteInfos(writeInfos);
+
+ for (WriteInfo* writeInfo : writeInfos) {
+ switch (writeInfo->GetType()) {
+ case WriteInfo::InsertItem: {
+ auto insertItemInfo = static_cast<InsertItemInfo*>(writeInfo);
+
+ LSSetItemInfo setItemInfo;
+ setItemInfo.key() = insertItemInfo->GetKey();
+ setItemInfo.value() = insertItemInfo->GetValue();
+
+ aWriteInfos.AppendElement(std::move(setItemInfo));
+
+ break;
+ }
+
+ case WriteInfo::UpdateItem: {
+ auto updateItemInfo = static_cast<UpdateItemInfo*>(writeInfo);
+
+ if (updateItemInfo->UpdateWithMove()) {
+ // See the comment in LSWriteOptimizer::InsertItem for more details
+ // about the UpdateWithMove flag.
+
+ LSRemoveItemInfo removeItemInfo;
+ removeItemInfo.key() = updateItemInfo->GetKey();
+
+ aWriteInfos.AppendElement(std::move(removeItemInfo));
+ }
+
+ LSSetItemInfo setItemInfo;
+ setItemInfo.key() = updateItemInfo->GetKey();
+ setItemInfo.value() = updateItemInfo->GetValue();
+
+ aWriteInfos.AppendElement(std::move(setItemInfo));
+
+ break;
+ }
+
+ case WriteInfo::DeleteItem: {
+ auto deleteItemInfo = static_cast<DeleteItemInfo*>(writeInfo);
+
+ LSRemoveItemInfo removeItemInfo;
+ removeItemInfo.key() = deleteItemInfo->GetKey();
+
+ aWriteInfos.AppendElement(std::move(removeItemInfo));
+
+ break;
+ }
+
+ case WriteInfo::Truncate: {
+ LSClearInfo clearInfo;
+
+ aWriteInfos.AppendElement(std::move(clearInfo));
+
+ break;
+ }
+
+ default:
+ MOZ_CRASH("Bad type!");
+ }
+ }
+}
+
+LSSnapshot::LSSnapshot(LSDatabase* aDatabase)
+ : mDatabase(aDatabase),
+ mActor(nullptr),
+ mInitLength(0),
+ mLength(0),
+ mUsage(0),
+ mPeakUsage(0),
+ mLoadState(LoadState::Initial),
+ mHasOtherProcessDatabases(false),
+ mHasOtherProcessObservers(false),
+ mExplicit(false),
+ mHasPendingStableStateCallback(false),
+ mHasPendingIdleTimerCallback(false),
+ mDirty(false)
+#ifdef DEBUG
+ ,
+ mInitialized(false),
+ mSentFinish(false)
+#endif
+{
+ AssertIsOnOwningThread();
+}
+
+LSSnapshot::~LSSnapshot() {
+ AssertIsOnOwningThread();
+ MOZ_ASSERT(mDatabase);
+ MOZ_ASSERT(!mHasPendingStableStateCallback);
+ MOZ_ASSERT(!mHasPendingIdleTimerCallback);
+ MOZ_ASSERT_IF(mInitialized, mSentFinish);
+
+ if (mActor) {
+ mActor->SendDeleteMeInternal();
+ MOZ_ASSERT(!mActor, "SendDeleteMeInternal should have cleared!");
+ }
+}
+
+void LSSnapshot::SetActor(LSSnapshotChild* aActor) {
+ AssertIsOnOwningThread();
+ MOZ_ASSERT(aActor);
+ MOZ_ASSERT(!mActor);
+
+ mActor = aActor;
+}
+
+nsresult LSSnapshot::Init(const nsAString& aKey,
+ const LSSnapshotInitInfo& aInitInfo, bool aExplicit) {
+ AssertIsOnOwningThread();
+ MOZ_ASSERT(!mSelfRef);
+ MOZ_ASSERT(mActor);
+ MOZ_ASSERT(mLoadState == LoadState::Initial);
+ MOZ_ASSERT(!mInitialized);
+ MOZ_ASSERT(!mSentFinish);
+
+ mSelfRef = this;
+
+ LoadState loadState = aInitInfo.loadState();
+
+ const nsTArray<LSItemInfo>& itemInfos = aInitInfo.itemInfos();
+ for (uint32_t i = 0; i < itemInfos.Length(); i++) {
+ const LSItemInfo& itemInfo = itemInfos[i];
+
+ const LSValue& value = itemInfo.value();
+
+ if (loadState != LoadState::AllOrderedItems && !value.IsVoid()) {
+ mLoadedItems.Insert(itemInfo.key());
+ }
+
+ mValues.InsertOrUpdate(itemInfo.key(), value.AsString());
+ }
+
+ if (loadState == LoadState::Partial) {
+ if (aInitInfo.addKeyToUnknownItems()) {
+ mUnknownItems.Insert(aKey);
+ }
+ mInitLength = aInitInfo.totalLength();
+ mLength = mInitLength;
+ } else if (loadState == LoadState::AllOrderedKeys) {
+ mInitLength = aInitInfo.totalLength();
+ } else {
+ MOZ_ASSERT(loadState == LoadState::AllOrderedItems);
+ }
+
+ mUsage = aInitInfo.usage();
+ mPeakUsage = aInitInfo.peakUsage();
+
+ mLoadState = aInitInfo.loadState();
+
+ mHasOtherProcessDatabases = aInitInfo.hasOtherProcessDatabases();
+ mHasOtherProcessObservers = aInitInfo.hasOtherProcessObservers();
+
+ mExplicit = aExplicit;
+
+#ifdef DEBUG
+ mInitialized = true;
+#endif
+
+ if (mHasOtherProcessObservers) {
+ mWriteAndNotifyInfos = MakeUnique<nsTArray<LSWriteAndNotifyInfo>>();
+ } else {
+ mWriteOptimizer = MakeUnique<SnapshotWriteOptimizer>();
+ }
+
+ if (!mExplicit) {
+ mIdleTimer = NS_NewTimer();
+ MOZ_ASSERT(mIdleTimer);
+
+ ScheduleStableStateCallback();
+ }
+
+ return NS_OK;
+}
+
+nsresult LSSnapshot::GetLength(uint32_t* aResult) {
+ AssertIsOnOwningThread();
+ MOZ_ASSERT(mActor);
+ MOZ_ASSERT(mInitialized);
+ MOZ_ASSERT(!mSentFinish);
+
+ MaybeScheduleStableStateCallback();
+
+ if (mLoadState == LoadState::Partial) {
+ *aResult = mLength;
+ } else {
+ *aResult = mValues.Count();
+ }
+
+ return NS_OK;
+}
+
+nsresult LSSnapshot::GetKey(uint32_t aIndex, nsAString& aResult) {
+ AssertIsOnOwningThread();
+ MOZ_ASSERT(mActor);
+ MOZ_ASSERT(mInitialized);
+ MOZ_ASSERT(!mSentFinish);
+
+ MaybeScheduleStableStateCallback();
+
+ nsresult rv = EnsureAllKeys();
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+
+ aResult.SetIsVoid(true);
+ for (auto iter = mValues.ConstIter(); !iter.Done(); iter.Next()) {
+ if (aIndex == 0) {
+ aResult = iter.Key();
+ return NS_OK;
+ }
+ aIndex--;
+ }
+
+ return NS_OK;
+}
+
+nsresult LSSnapshot::GetItem(const nsAString& aKey, nsAString& aResult) {
+ AssertIsOnOwningThread();
+ MOZ_ASSERT(mActor);
+ MOZ_ASSERT(mInitialized);
+ MOZ_ASSERT(!mSentFinish);
+
+ MaybeScheduleStableStateCallback();
+
+ nsString result;
+ nsresult rv = GetItemInternal(aKey, Optional<nsString>(), result);
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+
+ aResult = result;
+ return NS_OK;
+}
+
+nsresult LSSnapshot::GetKeys(nsTArray<nsString>& aKeys) {
+ AssertIsOnOwningThread();
+ MOZ_ASSERT(mActor);
+ MOZ_ASSERT(mInitialized);
+ MOZ_ASSERT(!mSentFinish);
+
+ MaybeScheduleStableStateCallback();
+
+ nsresult rv = EnsureAllKeys();
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+
+ AppendToArray(aKeys, mValues.Keys());
+
+ return NS_OK;
+}
+
+nsresult LSSnapshot::SetItem(const nsAString& aKey, const nsAString& aValue,
+ LSNotifyInfo& aNotifyInfo) {
+ AssertIsOnOwningThread();
+ MOZ_ASSERT(mActor);
+ MOZ_ASSERT(mInitialized);
+ MOZ_ASSERT(!mSentFinish);
+
+ MaybeScheduleStableStateCallback();
+
+ nsString oldValue;
+ nsresult rv =
+ GetItemInternal(aKey, Optional<nsString>(nsString(aValue)), oldValue);
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+
+ bool changed;
+ if (oldValue == aValue && oldValue.IsVoid() == aValue.IsVoid()) {
+ changed = false;
+ } else {
+ changed = true;
+
+ auto autoRevertValue = MakeScopeExit([&] {
+ if (oldValue.IsVoid()) {
+ mValues.Remove(aKey);
+ } else {
+ mValues.InsertOrUpdate(aKey, oldValue);
+ }
+ });
+
+ // Anything that can fail must be done early before we start modifying the
+ // state.
+
+ Maybe<LSValue> oldValueFromString;
+ if (mHasOtherProcessObservers) {
+ oldValueFromString.emplace();
+ if (NS_WARN_IF(!oldValueFromString->InitFromString(oldValue))) {
+ return NS_ERROR_FAILURE;
+ }
+ }
+
+ LSValue valueFromString;
+ if (NS_WARN_IF(!valueFromString.InitFromString(aValue))) {
+ return NS_ERROR_FAILURE;
+ }
+
+ int64_t delta = static_cast<int64_t>(aValue.Length()) -
+ static_cast<int64_t>(oldValue.Length());
+
+ if (oldValue.IsVoid()) {
+ delta += static_cast<int64_t>(aKey.Length());
+ }
+
+ rv = UpdateUsage(delta);
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+
+ if (oldValue.IsVoid() && mLoadState == LoadState::Partial) {
+ mLength++;
+ }
+
+ if (mHasOtherProcessObservers) {
+ MOZ_ASSERT(mWriteAndNotifyInfos);
+ MOZ_ASSERT(oldValueFromString.isSome());
+
+ LSSetItemAndNotifyInfo setItemAndNotifyInfo;
+ setItemAndNotifyInfo.key() = aKey;
+ setItemAndNotifyInfo.oldValue() = oldValueFromString.value();
+ setItemAndNotifyInfo.value() = valueFromString;
+
+ mWriteAndNotifyInfos->AppendElement(std::move(setItemAndNotifyInfo));
+ } else {
+ MOZ_ASSERT(mWriteOptimizer);
+
+ if (oldValue.IsVoid()) {
+ mWriteOptimizer->InsertItem(aKey, valueFromString);
+ } else {
+ mWriteOptimizer->UpdateItem(aKey, valueFromString);
+ }
+ }
+
+ autoRevertValue.release();
+ }
+
+ aNotifyInfo.changed() = changed;
+ aNotifyInfo.oldValue() = oldValue;
+
+ return NS_OK;
+}
+
+nsresult LSSnapshot::RemoveItem(const nsAString& aKey,
+ LSNotifyInfo& aNotifyInfo) {
+ AssertIsOnOwningThread();
+ MOZ_ASSERT(mActor);
+ MOZ_ASSERT(mInitialized);
+ MOZ_ASSERT(!mSentFinish);
+
+ MaybeScheduleStableStateCallback();
+
+ nsString oldValue;
+ nsresult rv =
+ GetItemInternal(aKey, Optional<nsString>(VoidString()), oldValue);
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+
+ bool changed;
+ if (oldValue.IsVoid()) {
+ changed = false;
+ } else {
+ changed = true;
+
+ auto autoRevertValue = MakeScopeExit([&] {
+ MOZ_ASSERT(!oldValue.IsVoid());
+ mValues.InsertOrUpdate(aKey, oldValue);
+ });
+
+ // Anything that can fail must be done early before we start modifying the
+ // state.
+
+ Maybe<LSValue> oldValueFromString;
+ if (mHasOtherProcessObservers) {
+ oldValueFromString.emplace();
+ if (NS_WARN_IF(!oldValueFromString->InitFromString(oldValue))) {
+ return NS_ERROR_FAILURE;
+ }
+ }
+
+ int64_t delta = -(static_cast<int64_t>(aKey.Length()) +
+ static_cast<int64_t>(oldValue.Length()));
+
+ DebugOnly<nsresult> rv = UpdateUsage(delta);
+ MOZ_ASSERT(NS_SUCCEEDED(rv));
+
+ if (mLoadState == LoadState::Partial) {
+ mLength--;
+ }
+
+ if (mHasOtherProcessObservers) {
+ MOZ_ASSERT(mWriteAndNotifyInfos);
+ MOZ_ASSERT(oldValueFromString.isSome());
+
+ LSRemoveItemAndNotifyInfo removeItemAndNotifyInfo;
+ removeItemAndNotifyInfo.key() = aKey;
+ removeItemAndNotifyInfo.oldValue() = oldValueFromString.value();
+
+ mWriteAndNotifyInfos->AppendElement(std::move(removeItemAndNotifyInfo));
+ } else {
+ MOZ_ASSERT(mWriteOptimizer);
+
+ mWriteOptimizer->DeleteItem(aKey);
+ }
+
+ autoRevertValue.release();
+ }
+
+ aNotifyInfo.changed() = changed;
+ aNotifyInfo.oldValue() = oldValue;
+
+ return NS_OK;
+}
+
+nsresult LSSnapshot::Clear(LSNotifyInfo& aNotifyInfo) {
+ AssertIsOnOwningThread();
+ MOZ_ASSERT(mActor);
+ MOZ_ASSERT(mInitialized);
+ MOZ_ASSERT(!mSentFinish);
+
+ MaybeScheduleStableStateCallback();
+
+ uint32_t length;
+ if (mLoadState == LoadState::Partial) {
+ length = mLength;
+ MOZ_ASSERT(length);
+
+ MOZ_ALWAYS_TRUE(mActor->SendLoaded());
+
+ mLoadedItems.Clear();
+ mUnknownItems.Clear();
+ mLength = 0;
+ mLoadState = LoadState::AllOrderedItems;
+ } else {
+ length = mValues.Count();
+ }
+
+ bool changed;
+ if (!length) {
+ changed = false;
+ } else {
+ changed = true;
+
+ int64_t delta = 0;
+ for (const auto& entry : mValues) {
+ const nsAString& key = entry.GetKey();
+ const nsString& value = entry.GetData();
+
+ delta += -static_cast<int64_t>(key.Length()) -
+ static_cast<int64_t>(value.Length());
+ }
+
+ DebugOnly<nsresult> rv = UpdateUsage(delta);
+ MOZ_ASSERT(NS_SUCCEEDED(rv));
+
+ mValues.Clear();
+
+ if (mHasOtherProcessObservers) {
+ MOZ_ASSERT(mWriteAndNotifyInfos);
+
+ LSClearInfo clearInfo;
+
+ mWriteAndNotifyInfos->AppendElement(std::move(clearInfo));
+ } else {
+ MOZ_ASSERT(mWriteOptimizer);
+
+ mWriteOptimizer->Truncate();
+ }
+ }
+
+ aNotifyInfo.changed() = changed;
+
+ return NS_OK;
+}
+
+void LSSnapshot::MarkDirty() {
+ AssertIsOnOwningThread();
+ MOZ_ASSERT(mActor);
+ MOZ_ASSERT(mInitialized);
+ MOZ_ASSERT(!mSentFinish);
+
+ if (mDirty) {
+ return;
+ }
+
+ mDirty = true;
+
+ if (!mExplicit && !mHasPendingStableStateCallback) {
+ CancelIdleTimer();
+
+ MOZ_ALWAYS_SUCCEEDS(Checkpoint());
+
+ MOZ_ALWAYS_SUCCEEDS(Finish());
+ } else {
+ MOZ_ASSERT(!mHasPendingIdleTimerCallback);
+ }
+}
+
+nsresult LSSnapshot::ExplicitCheckpoint() {
+ AssertIsOnOwningThread();
+ MOZ_ASSERT(mActor);
+ MOZ_ASSERT(mExplicit);
+ MOZ_ASSERT(!mHasPendingStableStateCallback);
+ MOZ_ASSERT(!mHasPendingIdleTimerCallback);
+ MOZ_ASSERT(mInitialized);
+ MOZ_ASSERT(!mSentFinish);
+
+ nsresult rv = Checkpoint(/* aSync */ true);
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+
+ return NS_OK;
+}
+
+nsresult LSSnapshot::ExplicitEnd() {
+ AssertIsOnOwningThread();
+ MOZ_ASSERT(mActor);
+ MOZ_ASSERT(mExplicit);
+ MOZ_ASSERT(!mHasPendingStableStateCallback);
+ MOZ_ASSERT(!mHasPendingIdleTimerCallback);
+ MOZ_ASSERT(mInitialized);
+ MOZ_ASSERT(!mSentFinish);
+
+ nsresult rv = Checkpoint();
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+
+ RefPtr<LSSnapshot> kungFuDeathGrip = this;
+
+ rv = Finish(/* aSync */ true);
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+
+ return NS_OK;
+}
+
+int64_t LSSnapshot::GetUsage() const {
+ AssertIsOnOwningThread();
+ MOZ_ASSERT(mActor);
+ MOZ_ASSERT(mInitialized);
+ MOZ_ASSERT(!mSentFinish);
+
+ return mUsage;
+}
+
+void LSSnapshot::ScheduleStableStateCallback() {
+ AssertIsOnOwningThread();
+ MOZ_ASSERT(mIdleTimer);
+ MOZ_ASSERT(!mExplicit);
+ MOZ_ASSERT(!mHasPendingStableStateCallback);
+
+ CancelIdleTimer();
+
+ nsCOMPtr<nsIRunnable> runnable = this;
+ nsContentUtils::RunInStableState(runnable.forget());
+
+ mHasPendingStableStateCallback = true;
+}
+
+void LSSnapshot::MaybeScheduleStableStateCallback() {
+ AssertIsOnOwningThread();
+
+ if (!mExplicit && !mHasPendingStableStateCallback) {
+ ScheduleStableStateCallback();
+ } else {
+ MOZ_ASSERT(!mHasPendingIdleTimerCallback);
+ }
+}
+
+nsresult LSSnapshot::GetItemInternal(const nsAString& aKey,
+ const Optional<nsString>& aValue,
+ nsAString& aResult) {
+ AssertIsOnOwningThread();
+ MOZ_ASSERT(mActor);
+ MOZ_ASSERT(mInitialized);
+ MOZ_ASSERT(!mSentFinish);
+
+ nsString result;
+
+ switch (mLoadState) {
+ case LoadState::Partial: {
+ if (mValues.Get(aKey, &result)) {
+ MOZ_ASSERT(!result.IsVoid());
+ } else if (mLoadedItems.Contains(aKey) || mUnknownItems.Contains(aKey)) {
+ result.SetIsVoid(true);
+ } else {
+ LSValue value;
+ nsTArray<LSItemInfo> itemInfos;
+ if (NS_WARN_IF(!mActor->SendLoadValueAndMoreItems(
+ nsString(aKey), &value, &itemInfos))) {
+ return NS_ERROR_FAILURE;
+ }
+
+ result = value.AsString();
+
+ if (result.IsVoid()) {
+ mUnknownItems.Insert(aKey);
+ } else {
+ mLoadedItems.Insert(aKey);
+ mValues.InsertOrUpdate(aKey, result);
+
+ // mLoadedItems.Count()==mInitLength is checked below.
+ }
+
+ for (uint32_t i = 0; i < itemInfos.Length(); i++) {
+ const LSItemInfo& itemInfo = itemInfos[i];
+
+ mLoadedItems.Insert(itemInfo.key());
+ mValues.InsertOrUpdate(itemInfo.key(), itemInfo.value().AsString());
+ }
+
+ if (mLoadedItems.Count() == mInitLength) {
+ mLoadedItems.Clear();
+ mUnknownItems.Clear();
+ mLength = 0;
+ mLoadState = LoadState::AllUnorderedItems;
+ }
+ }
+
+ if (aValue.WasPassed()) {
+ const nsString& value = aValue.Value();
+ if (!value.IsVoid()) {
+ mValues.InsertOrUpdate(aKey, value);
+ } else if (!result.IsVoid()) {
+ mValues.Remove(aKey);
+ }
+ }
+
+ break;
+ }
+
+ case LoadState::AllOrderedKeys: {
+ if (mValues.Get(aKey, &result)) {
+ if (result.IsVoid()) {
+ LSValue value;
+ nsTArray<LSItemInfo> itemInfos;
+ if (NS_WARN_IF(!mActor->SendLoadValueAndMoreItems(
+ nsString(aKey), &value, &itemInfos))) {
+ return NS_ERROR_FAILURE;
+ }
+
+ result = value.AsString();
+
+ MOZ_ASSERT(!result.IsVoid());
+
+ mLoadedItems.Insert(aKey);
+ mValues.InsertOrUpdate(aKey, result);
+
+ // mLoadedItems.Count()==mInitLength is checked below.
+
+ for (uint32_t i = 0; i < itemInfos.Length(); i++) {
+ const LSItemInfo& itemInfo = itemInfos[i];
+
+ mLoadedItems.Insert(itemInfo.key());
+ mValues.InsertOrUpdate(itemInfo.key(), itemInfo.value().AsString());
+ }
+
+ if (mLoadedItems.Count() == mInitLength) {
+ mLoadedItems.Clear();
+ MOZ_ASSERT(mLength == 0);
+ mLoadState = LoadState::AllOrderedItems;
+ }
+ }
+ } else {
+ result.SetIsVoid(true);
+ }
+
+ if (aValue.WasPassed()) {
+ const nsString& value = aValue.Value();
+ if (!value.IsVoid()) {
+ mValues.InsertOrUpdate(aKey, value);
+ } else if (!result.IsVoid()) {
+ mValues.Remove(aKey);
+ }
+ }
+
+ break;
+ }
+
+ case LoadState::AllUnorderedItems:
+ case LoadState::AllOrderedItems: {
+ if (aValue.WasPassed()) {
+ const nsString& value = aValue.Value();
+ if (!value.IsVoid()) {
+ mValues.WithEntryHandle(aKey, [&](auto&& entry) {
+ if (entry) {
+ result = std::exchange(entry.Data(), value);
+ } else {
+ result.SetIsVoid(true);
+ entry.Insert(value);
+ }
+ });
+ } else {
+ if (auto entry = mValues.Lookup(aKey)) {
+ result = entry.Data();
+ MOZ_ASSERT(!result.IsVoid());
+ entry.Remove();
+ } else {
+ result.SetIsVoid(true);
+ }
+ }
+ } else {
+ if (mValues.Get(aKey, &result)) {
+ MOZ_ASSERT(!result.IsVoid());
+ } else {
+ result.SetIsVoid(true);
+ }
+ }
+
+ break;
+ }
+
+ default:
+ MOZ_CRASH("Bad state!");
+ }
+
+ aResult = result;
+ return NS_OK;
+}
+
+nsresult LSSnapshot::EnsureAllKeys() {
+ AssertIsOnOwningThread();
+ MOZ_ASSERT(mActor);
+ MOZ_ASSERT(mInitialized);
+ MOZ_ASSERT(!mSentFinish);
+ MOZ_ASSERT(mLoadState != LoadState::Initial);
+
+ if (mLoadState == LoadState::AllOrderedKeys ||
+ mLoadState == LoadState::AllOrderedItems) {
+ return NS_OK;
+ }
+
+ nsTArray<nsString> keys;
+ if (NS_WARN_IF(!mActor->SendLoadKeys(&keys))) {
+ return NS_ERROR_FAILURE;
+ }
+
+ nsTHashMap<nsStringHashKey, nsString> newValues;
+
+ for (auto key : keys) {
+ newValues.InsertOrUpdate(key, VoidString());
+ }
+
+ if (mHasOtherProcessObservers) {
+ MOZ_ASSERT(mWriteAndNotifyInfos);
+
+ if (!mWriteAndNotifyInfos->IsEmpty()) {
+ for (uint32_t index = 0; index < mWriteAndNotifyInfos->Length();
+ index++) {
+ const LSWriteAndNotifyInfo& writeAndNotifyInfo =
+ mWriteAndNotifyInfos->ElementAt(index);
+
+ switch (writeAndNotifyInfo.type()) {
+ case LSWriteAndNotifyInfo::TLSSetItemAndNotifyInfo: {
+ newValues.InsertOrUpdate(
+ writeAndNotifyInfo.get_LSSetItemAndNotifyInfo().key(),
+ VoidString());
+ break;
+ }
+ case LSWriteAndNotifyInfo::TLSRemoveItemAndNotifyInfo: {
+ newValues.Remove(
+ writeAndNotifyInfo.get_LSRemoveItemAndNotifyInfo().key());
+ break;
+ }
+ case LSWriteAndNotifyInfo::TLSClearInfo: {
+ newValues.Clear();
+ break;
+ }
+
+ default:
+ MOZ_CRASH("Should never get here!");
+ }
+ }
+ }
+ } else {
+ MOZ_ASSERT(mWriteOptimizer);
+
+ if (mWriteOptimizer->HasWrites()) {
+ nsTArray<LSWriteInfo> writeInfos;
+ mWriteOptimizer->Enumerate(writeInfos);
+
+ MOZ_ASSERT(!writeInfos.IsEmpty());
+
+ for (uint32_t index = 0; index < writeInfos.Length(); index++) {
+ const LSWriteInfo& writeInfo = writeInfos[index];
+
+ switch (writeInfo.type()) {
+ case LSWriteInfo::TLSSetItemInfo: {
+ newValues.InsertOrUpdate(writeInfo.get_LSSetItemInfo().key(),
+ VoidString());
+ break;
+ }
+ case LSWriteInfo::TLSRemoveItemInfo: {
+ newValues.Remove(writeInfo.get_LSRemoveItemInfo().key());
+ break;
+ }
+ case LSWriteInfo::TLSClearInfo: {
+ newValues.Clear();
+ break;
+ }
+
+ default:
+ MOZ_CRASH("Should never get here!");
+ }
+ }
+ }
+ }
+
+ MOZ_ASSERT_IF(mLoadState == LoadState::AllUnorderedItems,
+ newValues.Count() == mValues.Count());
+
+ for (auto iter = newValues.Iter(); !iter.Done(); iter.Next()) {
+ nsString value;
+ if (mValues.Get(iter.Key(), &value)) {
+ iter.Data() = value;
+ }
+ }
+
+ mValues.SwapElements(newValues);
+
+ if (mLoadState == LoadState::Partial) {
+ mUnknownItems.Clear();
+ mLength = 0;
+ mLoadState = LoadState::AllOrderedKeys;
+ } else {
+ MOZ_ASSERT(mLoadState == LoadState::AllUnorderedItems);
+
+ MOZ_ASSERT(mUnknownItems.Count() == 0);
+ MOZ_ASSERT(mLength == 0);
+ mLoadState = LoadState::AllOrderedItems;
+ }
+
+ return NS_OK;
+}
+
+nsresult LSSnapshot::UpdateUsage(int64_t aDelta) {
+ AssertIsOnOwningThread();
+ MOZ_ASSERT(mDatabase);
+ MOZ_ASSERT(mActor);
+ MOZ_ASSERT(mPeakUsage >= mUsage);
+ MOZ_ASSERT(mInitialized);
+ MOZ_ASSERT(!mSentFinish);
+
+ int64_t newUsage = mUsage + aDelta;
+ if (newUsage > mPeakUsage) {
+ const int64_t minSize = newUsage - mPeakUsage;
+
+ int64_t size;
+ if (NS_WARN_IF(!mActor->SendIncreasePeakUsage(minSize, &size))) {
+ return NS_ERROR_FAILURE;
+ }
+
+ MOZ_ASSERT(size >= 0);
+
+ if (size == 0) {
+ return NS_ERROR_FILE_NO_DEVICE_SPACE;
+ }
+
+ mPeakUsage += size;
+ }
+
+ mUsage = newUsage;
+ return NS_OK;
+}
+
+nsresult LSSnapshot::Checkpoint(bool aSync) {
+ AssertIsOnOwningThread();
+ MOZ_ASSERT(mActor);
+ MOZ_ASSERT(mInitialized);
+ MOZ_ASSERT(!mSentFinish);
+
+ if (mHasOtherProcessObservers) {
+ MOZ_ASSERT(mWriteAndNotifyInfos);
+
+ if (!mWriteAndNotifyInfos->IsEmpty()) {
+ if (aSync) {
+ MOZ_ALWAYS_TRUE(
+ mActor->SendSyncCheckpointAndNotify(*mWriteAndNotifyInfos));
+ } else {
+ MOZ_ALWAYS_TRUE(
+ mActor->SendAsyncCheckpointAndNotify(*mWriteAndNotifyInfos));
+ }
+
+ mWriteAndNotifyInfos->Clear();
+ }
+ } else {
+ MOZ_ASSERT(mWriteOptimizer);
+
+ if (mWriteOptimizer->HasWrites()) {
+ nsTArray<LSWriteInfo> writeInfos;
+ mWriteOptimizer->Enumerate(writeInfos);
+
+ MOZ_ASSERT(!writeInfos.IsEmpty());
+
+ if (aSync) {
+ MOZ_ALWAYS_TRUE(mActor->SendSyncCheckpoint(writeInfos));
+ } else {
+ MOZ_ALWAYS_TRUE(mActor->SendAsyncCheckpoint(writeInfos));
+ }
+
+ mWriteOptimizer->Reset();
+ }
+ }
+
+ return NS_OK;
+}
+
+nsresult LSSnapshot::Finish(bool aSync) {
+ AssertIsOnOwningThread();
+ MOZ_ASSERT(mDatabase);
+ MOZ_ASSERT(mActor);
+ MOZ_ASSERT(mInitialized);
+ MOZ_ASSERT(!mSentFinish);
+
+ if (aSync) {
+ MOZ_ALWAYS_TRUE(mActor->SendSyncFinish());
+ } else {
+ MOZ_ALWAYS_TRUE(mActor->SendAsyncFinish());
+ }
+
+ mDatabase->NoteFinishedSnapshot(this);
+
+#ifdef DEBUG
+ mSentFinish = true;
+#endif
+
+ // Clear the self reference added in Init method.
+ MOZ_ASSERT(mSelfRef);
+ mSelfRef = nullptr;
+
+ return NS_OK;
+}
+
+void LSSnapshot::CancelIdleTimer() {
+ AssertIsOnOwningThread();
+ MOZ_ASSERT(mIdleTimer);
+
+ if (mHasPendingIdleTimerCallback) {
+ MOZ_ALWAYS_SUCCEEDS(mIdleTimer->Cancel());
+ mHasPendingIdleTimerCallback = false;
+ }
+}
+
+// static
+void LSSnapshot::IdleTimerCallback(nsITimer* aTimer, void* aClosure) {
+ MOZ_ASSERT(aTimer);
+
+ auto* self = static_cast<LSSnapshot*>(aClosure);
+ MOZ_ASSERT(self);
+ MOZ_ASSERT(self->mIdleTimer);
+ MOZ_ASSERT(SameCOMIdentity(self->mIdleTimer, aTimer));
+ MOZ_ASSERT(!self->mHasPendingStableStateCallback);
+ MOZ_ASSERT(self->mHasPendingIdleTimerCallback);
+
+ self->mHasPendingIdleTimerCallback = false;
+
+ MOZ_ALWAYS_SUCCEEDS(self->Finish());
+}
+
+NS_IMPL_ISUPPORTS(LSSnapshot, nsIRunnable)
+
+NS_IMETHODIMP
+LSSnapshot::Run() {
+ AssertIsOnOwningThread();
+ MOZ_ASSERT(!mExplicit);
+ MOZ_ASSERT(mHasPendingStableStateCallback);
+ MOZ_ASSERT(!mHasPendingIdleTimerCallback);
+
+ mHasPendingStableStateCallback = false;
+
+ MOZ_ALWAYS_SUCCEEDS(Checkpoint());
+
+ // 1. The unused pre-incremented snapshot peak usage can't be undone when
+ // there are other snapshots for the same database. We only add a pending
+ // usage delta when a snapshot finishes and usage deltas are then applied
+ // when the last database becomes inactive.
+ // 2. If there's a snapshot with pre-incremented peak usage, the next
+ // snapshot will use that as a base for its usage.
+ // 3. When a task for given snapshot finishes, we try to reuse the snapshot
+ // by only checkpointing the snapshot and delaying the finish by a timer.
+ // 4. If two or more tabs for the same origin use localStorage periodically
+ // at the same time the usage gradually grows until it hits the quota
+ // limit.
+ // 5. We prevent that from happening by finishing the snapshot immediatelly
+ // if there are databases in other processess.
+
+ if (mDirty || mHasOtherProcessDatabases ||
+ !Preferences::GetBool("dom.storage.snapshot_reusing")) {
+ MOZ_ALWAYS_SUCCEEDS(Finish());
+ } else {
+ MOZ_ASSERT(mIdleTimer);
+
+ MOZ_ALWAYS_SUCCEEDS(mIdleTimer->InitWithNamedFuncCallback(
+ IdleTimerCallback, this,
+ StaticPrefs::dom_storage_snapshot_idle_timeout_ms(),
+ nsITimer::TYPE_ONE_SHOT, "LSSnapshot::IdleTimerCallback"));
+
+ mHasPendingIdleTimerCallback = true;
+ }
+
+ return NS_OK;
+}
+
+} // namespace mozilla::dom