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/* -*- 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/quota/QuotaCommon.h"
#include "mozilla/dom/quota/ResultExtensions.h"
#include "mozilla/dom/quota/ScopedLogExtraInfo.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());
}
{
quota::ScopedLogExtraInfo scope{
quota::ScopedLogExtraInfo::kTagContextTainted,
"dom::localstorage::LSSnapshot::SetItem::UpdateUsage"_ns};
QM_TRY(MOZ_TO_RESULT(UpdateUsage(delta)), QM_PROPAGATE, QM_NO_CLEANUP,
([]() {
static uint32_t counter = 0u;
const bool result = 0u != (counter & (1u + counter));
++counter;
return result;
}));
}
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