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Diffstat (limited to 'docshell/base/SyncedContextInlines.h')
| -rw-r--r-- | docshell/base/SyncedContextInlines.h | 359 |
1 files changed, 359 insertions, 0 deletions
diff --git a/docshell/base/SyncedContextInlines.h b/docshell/base/SyncedContextInlines.h new file mode 100644 index 0000000000..e386e75b35 --- /dev/null +++ b/docshell/base/SyncedContextInlines.h @@ -0,0 +1,359 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=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/. */ + +#ifndef mozilla_dom_SyncedContextInlines_h +#define mozilla_dom_SyncedContextInlines_h + +#include "mozilla/dom/SyncedContext.h" +#include "mozilla/dom/BrowsingContextGroup.h" +#include "mozilla/dom/ContentParent.h" +#include "mozilla/dom/ContentChild.h" +#include "nsReadableUtils.h" +#include "mozilla/HalIPCUtils.h" + +namespace mozilla { +namespace dom { +namespace syncedcontext { + +template <typename T> +struct IsMozillaMaybe : std::false_type {}; +template <typename T> +struct IsMozillaMaybe<Maybe<T>> : std::true_type {}; + +// A super-sketchy logging only function for generating a human-readable version +// of the value of a synced context field. +template <typename T> +void FormatFieldValue(nsACString& aStr, const T& aValue) { + if constexpr (std::is_same_v<bool, T>) { + if (aValue) { + aStr.AppendLiteral("true"); + } else { + aStr.AppendLiteral("false"); + } + } else if constexpr (std::is_same_v<nsID, T>) { + aStr.Append(nsIDToCString(aValue).get()); + } else if constexpr (std::is_integral_v<T>) { + aStr.AppendInt(aValue); + } else if constexpr (std::is_enum_v<T>) { + aStr.AppendInt(static_cast<std::underlying_type_t<T>>(aValue)); + } else if constexpr (std::is_floating_point_v<T>) { + aStr.AppendFloat(aValue); + } else if constexpr (std::is_base_of_v<nsAString, T>) { + AppendUTF16toUTF8(aValue, aStr); + } else if constexpr (std::is_base_of_v<nsACString, T>) { + aStr.Append(aValue); + } else if constexpr (IsMozillaMaybe<T>::value) { + if (aValue) { + aStr.AppendLiteral("Some("); + FormatFieldValue(aStr, aValue.ref()); + aStr.AppendLiteral(")"); + } else { + aStr.AppendLiteral("Nothing"); + } + } else { + aStr.AppendLiteral("???"); + } +} + +// Sketchy logging-only logic to generate a human-readable output of the actions +// a synced context transaction is going to perform. +template <typename Context> +nsAutoCString FormatTransaction( + typename Transaction<Context>::IndexSet aModified, + const typename Context::FieldValues& aOldValues, + const typename Context::FieldValues& aNewValues) { + nsAutoCString result; + Context::FieldValues::EachIndex([&](auto idx) { + if (aModified.contains(idx)) { + result.Append(Context::FieldIndexToName(idx)); + result.AppendLiteral("("); + FormatFieldValue(result, aOldValues.Get(idx)); + result.AppendLiteral("->"); + FormatFieldValue(result, aNewValues.Get(idx)); + result.AppendLiteral(") "); + } + }); + return result; +} + +template <typename Context> +nsCString FormatValidationError( + typename Transaction<Context>::IndexSet aFailedFields, const char* prefix) { + MOZ_ASSERT(!aFailedFields.isEmpty()); + return nsDependentCString{prefix} + + StringJoin(", "_ns, aFailedFields, + [](nsACString& dest, const auto& idx) { + dest.Append(Context::FieldIndexToName(idx)); + }); +} + +template <typename Context> +nsresult Transaction<Context>::Commit(Context* aOwner) { + if (NS_WARN_IF(aOwner->IsDiscarded())) { + return NS_ERROR_DOM_INVALID_STATE_ERR; + } + + IndexSet failedFields = Validate(aOwner, nullptr); + if (!failedFields.isEmpty()) { + nsCString error = FormatValidationError<Context>( + failedFields, "CanSet failed for field(s): "); + MOZ_CRASH_UNSAFE_PRINTF("%s", error.get()); + } + + if (mModified.isEmpty()) { + return NS_OK; + } + + if (XRE_IsContentProcess()) { + ContentChild* cc = ContentChild::GetSingleton(); + + // Increment the field epoch for fields affected by this transaction. + uint64_t epoch = cc->NextBrowsingContextFieldEpoch(); + EachIndex([&](auto idx) { + if (mModified.contains(idx)) { + FieldEpoch(idx, aOwner) = epoch; + } + }); + + // Tell our derived class to send the correct "Commit" IPC message. + aOwner->SendCommitTransaction(cc, *this, epoch); + } else { + MOZ_DIAGNOSTIC_ASSERT(XRE_IsParentProcess()); + + // Tell our derived class to send the correct "Commit" IPC messages. + BrowsingContextGroup* group = aOwner->Group(); + group->EachParent([&](ContentParent* aParent) { + aOwner->SendCommitTransaction(aParent, *this, + aParent->GetBrowsingContextFieldEpoch()); + }); + } + + Apply(aOwner, /* aFromIPC */ false); + return NS_OK; +} + +template <typename Context> +mozilla::ipc::IPCResult Transaction<Context>::CommitFromIPC( + const MaybeDiscarded<Context>& aOwner, ContentParent* aSource) { + MOZ_DIAGNOSTIC_ASSERT(XRE_IsParentProcess()); + if (aOwner.IsNullOrDiscarded()) { + MOZ_LOG(Context::GetSyncLog(), LogLevel::Debug, + ("IPC: Trying to send a message to dead or detached context")); + return IPC_OK(); + } + Context* owner = aOwner.get(); + + // Validate that the set from content is allowed before continuing. + IndexSet failedFields = Validate(owner, aSource); + if (!failedFields.isEmpty()) { + nsCString error = FormatValidationError<Context>( + failedFields, + "Invalid Transaction from Child - CanSet failed for field(s): "); + // data-review+ at https://bugzilla.mozilla.org/show_bug.cgi?id=1618992#c7 + return IPC_FAIL_UNSAFE_PRINTF(aSource, "%s", error.get()); + } + + // Validate may have dropped some fields from the transaction, check it's not + // empty before continuing. + if (mModified.isEmpty()) { + return IPC_OK(); + } + + BrowsingContextGroup* group = owner->Group(); + group->EachOtherParent(aSource, [&](ContentParent* aParent) { + owner->SendCommitTransaction(aParent, *this, + aParent->GetBrowsingContextFieldEpoch()); + }); + + Apply(owner, /* aFromIPC */ true); + return IPC_OK(); +} + +template <typename Context> +mozilla::ipc::IPCResult Transaction<Context>::CommitFromIPC( + const MaybeDiscarded<Context>& aOwner, uint64_t aEpoch, + ContentChild* aSource) { + MOZ_DIAGNOSTIC_ASSERT(XRE_IsContentProcess()); + if (aOwner.IsNullOrDiscarded()) { + MOZ_LOG(Context::GetSyncLog(), LogLevel::Debug, + ("ChildIPC: Trying to send a message to dead or detached context")); + return IPC_OK(); + } + Context* owner = aOwner.get(); + + // Clear any fields which have been obsoleted by the epoch. + EachIndex([&](auto idx) { + if (mModified.contains(idx) && FieldEpoch(idx, owner) > aEpoch) { + MOZ_LOG( + Context::GetSyncLog(), LogLevel::Debug, + ("Transaction::Obsoleted(#%" PRIx64 ", %" PRIu64 ">%" PRIu64 "): %s", + owner->Id(), FieldEpoch(idx, owner), aEpoch, + Context::FieldIndexToName(idx))); + mModified -= idx; + } + }); + + if (mModified.isEmpty()) { + return IPC_OK(); + } + + Apply(owner, /* aFromIPC */ true); + return IPC_OK(); +} + +template <typename Context> +void Transaction<Context>::Apply(Context* aOwner, bool aFromIPC) { + MOZ_ASSERT(!mModified.isEmpty()); + + MOZ_LOG( + Context::GetSyncLog(), LogLevel::Debug, + ("Transaction::Apply(#%" PRIx64 ", %s): %s", aOwner->Id(), + aFromIPC ? "ipc" : "local", + FormatTransaction<Context>(mModified, aOwner->mFields.mValues, mValues) + .get())); + + EachIndex([&](auto idx) { + if (mModified.contains(idx)) { + auto& txnField = mValues.Get(idx); + auto& ownerField = aOwner->mFields.mValues.Get(idx); + std::swap(ownerField, txnField); + aOwner->DidSet(idx); + aOwner->DidSet(idx, std::move(txnField)); + } + }); + mModified.clear(); +} + +template <typename Context> +void Transaction<Context>::CommitWithoutSyncing(Context* aOwner) { + MOZ_LOG( + Context::GetSyncLog(), LogLevel::Debug, + ("Transaction::CommitWithoutSyncing(#%" PRIx64 "): %s", aOwner->Id(), + FormatTransaction<Context>(mModified, aOwner->mFields.mValues, mValues) + .get())); + + EachIndex([&](auto idx) { + if (mModified.contains(idx)) { + aOwner->mFields.mValues.Get(idx) = std::move(mValues.Get(idx)); + } + }); + mModified.clear(); +} + +inline CanSetResult AsCanSetResult(CanSetResult aValue) { return aValue; } +inline CanSetResult AsCanSetResult(bool aValue) { + return aValue ? CanSetResult::Allow : CanSetResult::Deny; +} + +template <typename Context> +typename Transaction<Context>::IndexSet Transaction<Context>::Validate( + Context* aOwner, ContentParent* aSource) { + IndexSet failedFields; + Transaction<Context> revertTxn; + + EachIndex([&](auto idx) { + if (!mModified.contains(idx)) { + return; + } + + switch (AsCanSetResult(aOwner->CanSet(idx, mValues.Get(idx), aSource))) { + case CanSetResult::Allow: + break; + case CanSetResult::Deny: + failedFields += idx; + break; + case CanSetResult::Revert: + revertTxn.mValues.Get(idx) = aOwner->mFields.mValues.Get(idx); + revertTxn.mModified += idx; + break; + } + }); + + // If any changes need to be reverted, log them, remove them from this + // transaction, and optionally send a message to the source process. + if (!revertTxn.mModified.isEmpty()) { + // NOTE: Logging with modified IndexSet from revert transaction, and values + // from this transaction, so we log the failed values we're going to revert. + MOZ_LOG( + Context::GetSyncLog(), LogLevel::Debug, + ("Transaction::PartialRevert(#%" PRIx64 ", pid %" PRIPID "): %s", + aOwner->Id(), aSource ? aSource->OtherPid() : base::kInvalidProcessId, + FormatTransaction<Context>(revertTxn.mModified, mValues, + revertTxn.mValues) + .get())); + + mModified -= revertTxn.mModified; + + if (aSource) { + aOwner->SendCommitTransaction(aSource, revertTxn, + aSource->GetBrowsingContextFieldEpoch()); + } + } + return failedFields; +} + +template <typename Context> +void Transaction<Context>::Write(IPC::MessageWriter* aWriter, + mozilla::ipc::IProtocol* aActor) const { + // Record which field indices will be included, and then write those fields + // out. + typename IndexSet::serializedType modified = mModified.serialize(); + WriteIPDLParam(aWriter, aActor, modified); + EachIndex([&](auto idx) { + if (mModified.contains(idx)) { + WriteIPDLParam(aWriter, aActor, mValues.Get(idx)); + } + }); +} + +template <typename Context> +bool Transaction<Context>::Read(IPC::MessageReader* aReader, + mozilla::ipc::IProtocol* aActor) { + // Read in which field indices were sent by the remote, followed by the fields + // identified by those indices. + typename IndexSet::serializedType modified = + typename IndexSet::serializedType{}; + if (!ReadIPDLParam(aReader, aActor, &modified)) { + return false; + } + mModified.deserialize(modified); + + bool ok = true; + EachIndex([&](auto idx) { + if (ok && mModified.contains(idx)) { + ok = ReadIPDLParam(aReader, aActor, &mValues.Get(idx)); + } + }); + return ok; +} + +template <typename Base, size_t Count> +void FieldValues<Base, Count>::Write(IPC::MessageWriter* aWriter, + mozilla::ipc::IProtocol* aActor) const { + // XXX The this-> qualification is necessary to work around a bug in older gcc + // versions causing an ICE. + EachIndex([&](auto idx) { WriteIPDLParam(aWriter, aActor, this->Get(idx)); }); +} + +template <typename Base, size_t Count> +bool FieldValues<Base, Count>::Read(IPC::MessageReader* aReader, + mozilla::ipc::IProtocol* aActor) { + bool ok = true; + EachIndex([&](auto idx) { + if (ok) { + // XXX The this-> qualification is necessary to work around a bug in older + // gcc versions causing an ICE. + ok = ReadIPDLParam(aReader, aActor, &this->Get(idx)); + } + }); + return ok; +} + +} // namespace syncedcontext +} // namespace dom +} // namespace mozilla + +#endif // !defined(mozilla_dom_SyncedContextInlines_h) |