// Copyright (c) 2018-2020 The Bitcoin Core developers // Distributed under the MIT software license, see the accompanying // file COPYING or http://www.opensource.org/licenses/mit-license.php. #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #if defined(HAVE_CONFIG_H) #include #endif #include #include using interfaces::BlockTip; using interfaces::Chain; using interfaces::FoundBlock; using interfaces::Handler; using interfaces::MakeHandler; using interfaces::Node; using interfaces::WalletClient; namespace node { namespace { class NodeImpl : public Node { public: explicit NodeImpl(NodeContext* context) { setContext(context); } void initLogging() override { InitLogging(*Assert(m_context->args)); } void initParameterInteraction() override { InitParameterInteraction(*Assert(m_context->args)); } bilingual_str getWarnings() override { return GetWarnings(true); } uint32_t getLogCategories() override { return LogInstance().GetCategoryMask(); } bool baseInitialize() override { return AppInitBasicSetup(gArgs) && AppInitParameterInteraction(gArgs) && AppInitSanityChecks() && AppInitLockDataDirectory() && AppInitInterfaces(*m_context); } bool appInitMain(interfaces::BlockAndHeaderTipInfo* tip_info) override { return AppInitMain(m_context_ref, *m_context, tip_info); } void appShutdown() override { Interrupt(*m_context); Shutdown(*m_context); } void startShutdown() override { StartShutdown(); // Stop RPC for clean shutdown if any of waitfor* commands is executed. if (gArgs.GetBoolArg("-server", false)) { InterruptRPC(); StopRPC(); } } bool shutdownRequested() override { return ShutdownRequested(); } void mapPort(bool use_upnp, bool use_natpmp) override { StartMapPort(use_upnp, use_natpmp); } bool getProxy(Network net, proxyType& proxy_info) override { return GetProxy(net, proxy_info); } size_t getNodeCount(ConnectionDirection flags) override { return m_context->connman ? m_context->connman->GetNodeCount(flags) : 0; } bool getNodesStats(NodesStats& stats) override { stats.clear(); if (m_context->connman) { std::vector stats_temp; m_context->connman->GetNodeStats(stats_temp); stats.reserve(stats_temp.size()); for (auto& node_stats_temp : stats_temp) { stats.emplace_back(std::move(node_stats_temp), false, CNodeStateStats()); } // Try to retrieve the CNodeStateStats for each node. if (m_context->peerman) { TRY_LOCK(::cs_main, lockMain); if (lockMain) { for (auto& node_stats : stats) { std::get<1>(node_stats) = m_context->peerman->GetNodeStateStats(std::get<0>(node_stats).nodeid, std::get<2>(node_stats)); } } } return true; } return false; } bool getBanned(banmap_t& banmap) override { if (m_context->banman) { m_context->banman->GetBanned(banmap); return true; } return false; } bool ban(const CNetAddr& net_addr, int64_t ban_time_offset) override { if (m_context->banman) { m_context->banman->Ban(net_addr, ban_time_offset); return true; } return false; } bool unban(const CSubNet& ip) override { if (m_context->banman) { m_context->banman->Unban(ip); return true; } return false; } bool disconnectByAddress(const CNetAddr& net_addr) override { if (m_context->connman) { return m_context->connman->DisconnectNode(net_addr); } return false; } bool disconnectById(NodeId id) override { if (m_context->connman) { return m_context->connman->DisconnectNode(id); } return false; } int64_t getTotalBytesRecv() override { return m_context->connman ? m_context->connman->GetTotalBytesRecv() : 0; } int64_t getTotalBytesSent() override { return m_context->connman ? m_context->connman->GetTotalBytesSent() : 0; } size_t getMempoolSize() override { return m_context->mempool ? m_context->mempool->size() : 0; } size_t getMempoolDynamicUsage() override { return m_context->mempool ? m_context->mempool->DynamicMemoryUsage() : 0; } bool getHeaderTip(int& height, int64_t& block_time) override { LOCK(::cs_main); if (::pindexBestHeader) { height = ::pindexBestHeader->nHeight; block_time = ::pindexBestHeader->GetBlockTime(); return true; } return false; } int getNumBlocks() override { LOCK(::cs_main); assert(std::addressof(::ChainActive()) == std::addressof(m_context->chainman->ActiveChain())); return m_context->chainman->ActiveChain().Height(); } uint256 getBestBlockHash() override { assert(std::addressof(::ChainActive()) == std::addressof(m_context->chainman->ActiveChain())); const CBlockIndex* tip = WITH_LOCK(::cs_main, return m_context->chainman->ActiveChain().Tip()); return tip ? tip->GetBlockHash() : Params().GenesisBlock().GetHash(); } int64_t getLastBlockTime() override { LOCK(::cs_main); assert(std::addressof(::ChainActive()) == std::addressof(m_context->chainman->ActiveChain())); if (m_context->chainman->ActiveChain().Tip()) { return m_context->chainman->ActiveChain().Tip()->GetBlockTime(); } return Params().GenesisBlock().GetBlockTime(); // Genesis block's time of current network } double getVerificationProgress() override { const CBlockIndex* tip; { LOCK(::cs_main); assert(std::addressof(::ChainActive()) == std::addressof(m_context->chainman->ActiveChain())); tip = m_context->chainman->ActiveChain().Tip(); } return GuessVerificationProgress(Params().TxData(), tip); } bool isInitialBlockDownload() override { assert(std::addressof(::ChainstateActive()) == std::addressof(m_context->chainman->ActiveChainstate())); return m_context->chainman->ActiveChainstate().IsInitialBlockDownload(); } bool getReindex() override { return ::fReindex; } bool getImporting() override { return ::fImporting; } void setNetworkActive(bool active) override { if (m_context->connman) { m_context->connman->SetNetworkActive(active); } } bool getNetworkActive() override { return m_context->connman && m_context->connman->GetNetworkActive(); } CFeeRate getDustRelayFee() override { return ::dustRelayFee; } UniValue executeRpc(const std::string& command, const UniValue& params, const std::string& uri) override { JSONRPCRequest req(m_context_ref); req.params = params; req.strMethod = command; req.URI = uri; return ::tableRPC.execute(req); } std::vector listRpcCommands() override { return ::tableRPC.listCommands(); } void rpcSetTimerInterfaceIfUnset(RPCTimerInterface* iface) override { RPCSetTimerInterfaceIfUnset(iface); } void rpcUnsetTimerInterface(RPCTimerInterface* iface) override { RPCUnsetTimerInterface(iface); } bool getUnspentOutput(const COutPoint& output, Coin& coin) override { LOCK(::cs_main); assert(std::addressof(::ChainstateActive()) == std::addressof(m_context->chainman->ActiveChainstate())); return m_context->chainman->ActiveChainstate().CoinsTip().GetCoin(output, coin); } WalletClient& walletClient() override { return *Assert(m_context->wallet_client); } std::unique_ptr handleInitMessage(InitMessageFn fn) override { return MakeHandler(::uiInterface.InitMessage_connect(fn)); } std::unique_ptr handleMessageBox(MessageBoxFn fn) override { return MakeHandler(::uiInterface.ThreadSafeMessageBox_connect(fn)); } std::unique_ptr handleQuestion(QuestionFn fn) override { return MakeHandler(::uiInterface.ThreadSafeQuestion_connect(fn)); } std::unique_ptr handleShowProgress(ShowProgressFn fn) override { return MakeHandler(::uiInterface.ShowProgress_connect(fn)); } std::unique_ptr handleNotifyNumConnectionsChanged(NotifyNumConnectionsChangedFn fn) override { return MakeHandler(::uiInterface.NotifyNumConnectionsChanged_connect(fn)); } std::unique_ptr handleNotifyNetworkActiveChanged(NotifyNetworkActiveChangedFn fn) override { return MakeHandler(::uiInterface.NotifyNetworkActiveChanged_connect(fn)); } std::unique_ptr handleNotifyAlertChanged(NotifyAlertChangedFn fn) override { return MakeHandler(::uiInterface.NotifyAlertChanged_connect(fn)); } std::unique_ptr handleBannedListChanged(BannedListChangedFn fn) override { return MakeHandler(::uiInterface.BannedListChanged_connect(fn)); } std::unique_ptr handleNotifyBlockTip(NotifyBlockTipFn fn) override { return MakeHandler(::uiInterface.NotifyBlockTip_connect([fn](SynchronizationState sync_state, const CBlockIndex* block) { fn(sync_state, BlockTip{block->nHeight, block->GetBlockTime(), block->GetBlockHash()}, GuessVerificationProgress(Params().TxData(), block)); })); } std::unique_ptr handleNotifyHeaderTip(NotifyHeaderTipFn fn) override { return MakeHandler( ::uiInterface.NotifyHeaderTip_connect([fn](SynchronizationState sync_state, const CBlockIndex* block) { fn(sync_state, BlockTip{block->nHeight, block->GetBlockTime(), block->GetBlockHash()}, /* verification progress is unused when a header was received */ 0); })); } NodeContext* context() override { return m_context; } void setContext(NodeContext* context) override { m_context = context; if (context) { m_context_ref.Set(*context); } else { m_context_ref.Clear(); } } NodeContext* m_context{nullptr}; util::Ref m_context_ref; }; bool FillBlock(const CBlockIndex* index, const FoundBlock& block, UniqueLock& lock, const CChain& active) { if (!index) return false; if (block.m_hash) *block.m_hash = index->GetBlockHash(); if (block.m_height) *block.m_height = index->nHeight; if (block.m_time) *block.m_time = index->GetBlockTime(); if (block.m_max_time) *block.m_max_time = index->GetBlockTimeMax(); if (block.m_mtp_time) *block.m_mtp_time = index->GetMedianTimePast(); if (block.m_in_active_chain) *block.m_in_active_chain = active[index->nHeight] == index; if (block.m_next_block) FillBlock(active[index->nHeight] == index ? active[index->nHeight + 1] : nullptr, *block.m_next_block, lock, active); if (block.m_data) { REVERSE_LOCK(lock); if (!ReadBlockFromDisk(*block.m_data, index, Params().GetConsensus())) block.m_data->SetNull(); } return true; } class NotificationsProxy : public CValidationInterface { public: explicit NotificationsProxy(std::shared_ptr notifications) : m_notifications(std::move(notifications)) {} virtual ~NotificationsProxy() = default; void TransactionAddedToMempool(const CTransactionRef& tx, uint64_t mempool_sequence) override { m_notifications->transactionAddedToMempool(tx, mempool_sequence); } void TransactionRemovedFromMempool(const CTransactionRef& tx, MemPoolRemovalReason reason, uint64_t mempool_sequence) override { m_notifications->transactionRemovedFromMempool(tx, reason, mempool_sequence); } void BlockConnected(const std::shared_ptr& block, const CBlockIndex* index) override { m_notifications->blockConnected(*block, index->nHeight); } void BlockDisconnected(const std::shared_ptr& block, const CBlockIndex* index) override { m_notifications->blockDisconnected(*block, index->nHeight); } void UpdatedBlockTip(const CBlockIndex* index, const CBlockIndex* fork_index, bool is_ibd) override { m_notifications->updatedBlockTip(); } void ChainStateFlushed(const CBlockLocator& locator) override { m_notifications->chainStateFlushed(locator); } std::shared_ptr m_notifications; }; class NotificationsHandlerImpl : public Handler { public: explicit NotificationsHandlerImpl(std::shared_ptr notifications) : m_proxy(std::make_shared(std::move(notifications))) { RegisterSharedValidationInterface(m_proxy); } ~NotificationsHandlerImpl() override { disconnect(); } void disconnect() override { if (m_proxy) { UnregisterSharedValidationInterface(m_proxy); m_proxy.reset(); } } std::shared_ptr m_proxy; }; class RpcHandlerImpl : public Handler { public: explicit RpcHandlerImpl(const CRPCCommand& command) : m_command(command), m_wrapped_command(&command) { m_command.actor = [this](const JSONRPCRequest& request, UniValue& result, bool last_handler) { if (!m_wrapped_command) return false; try { return m_wrapped_command->actor(request, result, last_handler); } catch (const UniValue& e) { // If this is not the last handler and a wallet not found // exception was thrown, return false so the next handler can // try to handle the request. Otherwise, reraise the exception. if (!last_handler) { const UniValue& code = e["code"]; if (code.isNum() && code.get_int() == RPC_WALLET_NOT_FOUND) { return false; } } throw; } }; ::tableRPC.appendCommand(m_command.name, &m_command); } void disconnect() final { if (m_wrapped_command) { m_wrapped_command = nullptr; ::tableRPC.removeCommand(m_command.name, &m_command); } } ~RpcHandlerImpl() override { disconnect(); } CRPCCommand m_command; const CRPCCommand* m_wrapped_command; }; class ChainImpl : public Chain { public: explicit ChainImpl(NodeContext& node) : m_node(node) {} Optional getHeight() override { LOCK(::cs_main); const CChain& active = Assert(m_node.chainman)->ActiveChain(); int height = active.Height(); if (height >= 0) { return height; } return nullopt; } uint256 getBlockHash(int height) override { LOCK(::cs_main); const CChain& active = Assert(m_node.chainman)->ActiveChain(); CBlockIndex* block = active[height]; assert(block); return block->GetBlockHash(); } bool haveBlockOnDisk(int height) override { LOCK(cs_main); const CChain& active = Assert(m_node.chainman)->ActiveChain(); CBlockIndex* block = active[height]; return block && ((block->nStatus & BLOCK_HAVE_DATA) != 0) && block->nTx > 0; } CBlockLocator getTipLocator() override { LOCK(cs_main); const CChain& active = Assert(m_node.chainman)->ActiveChain(); return active.GetLocator(); } bool checkFinalTx(const CTransaction& tx) override { LOCK(cs_main); assert(std::addressof(::ChainActive()) == std::addressof(m_node.chainman->ActiveChain())); return CheckFinalTx(m_node.chainman->ActiveChain().Tip(), tx); } Optional findLocatorFork(const CBlockLocator& locator) override { LOCK(cs_main); const CChain& active = Assert(m_node.chainman)->ActiveChain(); assert(std::addressof(g_chainman) == std::addressof(*m_node.chainman)); if (CBlockIndex* fork = m_node.chainman->m_blockman.FindForkInGlobalIndex(active, locator)) { return fork->nHeight; } return nullopt; } bool findBlock(const uint256& hash, const FoundBlock& block) override { WAIT_LOCK(cs_main, lock); const CChain& active = Assert(m_node.chainman)->ActiveChain(); assert(std::addressof(g_chainman) == std::addressof(*m_node.chainman)); return FillBlock(m_node.chainman->m_blockman.LookupBlockIndex(hash), block, lock, active); } bool findFirstBlockWithTimeAndHeight(int64_t min_time, int min_height, const FoundBlock& block) override { WAIT_LOCK(cs_main, lock); const CChain& active = Assert(m_node.chainman)->ActiveChain(); return FillBlock(active.FindEarliestAtLeast(min_time, min_height), block, lock, active); } bool findAncestorByHeight(const uint256& block_hash, int ancestor_height, const FoundBlock& ancestor_out) override { WAIT_LOCK(cs_main, lock); const CChain& active = Assert(m_node.chainman)->ActiveChain(); assert(std::addressof(g_chainman) == std::addressof(*m_node.chainman)); if (const CBlockIndex* block = m_node.chainman->m_blockman.LookupBlockIndex(block_hash)) { if (const CBlockIndex* ancestor = block->GetAncestor(ancestor_height)) { return FillBlock(ancestor, ancestor_out, lock, active); } } return FillBlock(nullptr, ancestor_out, lock, active); } bool findAncestorByHash(const uint256& block_hash, const uint256& ancestor_hash, const FoundBlock& ancestor_out) override { WAIT_LOCK(cs_main, lock); const CChain& active = Assert(m_node.chainman)->ActiveChain(); assert(std::addressof(g_chainman) == std::addressof(*m_node.chainman)); const CBlockIndex* block = m_node.chainman->m_blockman.LookupBlockIndex(block_hash); assert(std::addressof(g_chainman) == std::addressof(*m_node.chainman)); const CBlockIndex* ancestor = m_node.chainman->m_blockman.LookupBlockIndex(ancestor_hash); if (block && ancestor && block->GetAncestor(ancestor->nHeight) != ancestor) ancestor = nullptr; return FillBlock(ancestor, ancestor_out, lock, active); } bool findCommonAncestor(const uint256& block_hash1, const uint256& block_hash2, const FoundBlock& ancestor_out, const FoundBlock& block1_out, const FoundBlock& block2_out) override { WAIT_LOCK(cs_main, lock); const CChain& active = Assert(m_node.chainman)->ActiveChain(); assert(std::addressof(g_chainman) == std::addressof(*m_node.chainman)); const CBlockIndex* block1 = m_node.chainman->m_blockman.LookupBlockIndex(block_hash1); assert(std::addressof(g_chainman) == std::addressof(*m_node.chainman)); const CBlockIndex* block2 = m_node.chainman->m_blockman.LookupBlockIndex(block_hash2); const CBlockIndex* ancestor = block1 && block2 ? LastCommonAncestor(block1, block2) : nullptr; // Using & instead of && below to avoid short circuiting and leaving // output uninitialized. return FillBlock(ancestor, ancestor_out, lock, active) & FillBlock(block1, block1_out, lock, active) & FillBlock(block2, block2_out, lock, active); } void findCoins(std::map& coins) override { return FindCoins(m_node, coins); } double guessVerificationProgress(const uint256& block_hash) override { LOCK(cs_main); assert(std::addressof(g_chainman) == std::addressof(*m_node.chainman)); return GuessVerificationProgress(Params().TxData(), m_node.chainman->m_blockman.LookupBlockIndex(block_hash)); } bool hasBlocks(const uint256& block_hash, int min_height, Optional max_height) override { // hasBlocks returns true if all ancestors of block_hash in specified // range have block data (are not pruned), false if any ancestors in // specified range are missing data. // // For simplicity and robustness, min_height and max_height are only // used to limit the range, and passing min_height that's too low or // max_height that's too high will not crash or change the result. LOCK(::cs_main); assert(std::addressof(g_chainman) == std::addressof(*m_node.chainman)); if (CBlockIndex* block = m_node.chainman->m_blockman.LookupBlockIndex(block_hash)) { if (max_height && block->nHeight >= *max_height) block = block->GetAncestor(*max_height); for (; block->nStatus & BLOCK_HAVE_DATA; block = block->pprev) { // Check pprev to not segfault if min_height is too low if (block->nHeight <= min_height || !block->pprev) return true; } } return false; } RBFTransactionState isRBFOptIn(const CTransaction& tx) override { if (!m_node.mempool) return IsRBFOptInEmptyMempool(tx); LOCK(m_node.mempool->cs); return IsRBFOptIn(tx, *m_node.mempool); } bool isInMempool(const uint256& txid) override { if (!m_node.mempool) return false; LOCK(m_node.mempool->cs); return m_node.mempool->exists(txid); } bool hasDescendantsInMempool(const uint256& txid) override { if (!m_node.mempool) return false; LOCK(m_node.mempool->cs); auto it = m_node.mempool->GetIter(txid); return it && (*it)->GetCountWithDescendants() > 1; } bool broadcastTransaction(const CTransactionRef& tx, const CAmount& max_tx_fee, bool relay, std::string& err_string) override { const TransactionError err = BroadcastTransaction(m_node, tx, err_string, max_tx_fee, relay, /*wait_callback*/ false); // Chain clients only care about failures to accept the tx to the mempool. Disregard non-mempool related failures. // Note: this will need to be updated if BroadcastTransactions() is updated to return other non-mempool failures // that Chain clients do not need to know about. return TransactionError::OK == err; } void getTransactionAncestry(const uint256& txid, size_t& ancestors, size_t& descendants) override { ancestors = descendants = 0; if (!m_node.mempool) return; m_node.mempool->GetTransactionAncestry(txid, ancestors, descendants); } void getPackageLimits(unsigned int& limit_ancestor_count, unsigned int& limit_descendant_count) override { limit_ancestor_count = gArgs.GetArg("-limitancestorcount", DEFAULT_ANCESTOR_LIMIT); limit_descendant_count = gArgs.GetArg("-limitdescendantcount", DEFAULT_DESCENDANT_LIMIT); } bool checkChainLimits(const CTransactionRef& tx) override { if (!m_node.mempool) return true; LockPoints lp; CTxMemPoolEntry entry(tx, 0, 0, 0, false, 0, lp); CTxMemPool::setEntries ancestors; auto limit_ancestor_count = gArgs.GetArg("-limitancestorcount", DEFAULT_ANCESTOR_LIMIT); auto limit_ancestor_size = gArgs.GetArg("-limitancestorsize", DEFAULT_ANCESTOR_SIZE_LIMIT) * 1000; auto limit_descendant_count = gArgs.GetArg("-limitdescendantcount", DEFAULT_DESCENDANT_LIMIT); auto limit_descendant_size = gArgs.GetArg("-limitdescendantsize", DEFAULT_DESCENDANT_SIZE_LIMIT) * 1000; std::string unused_error_string; LOCK(m_node.mempool->cs); return m_node.mempool->CalculateMemPoolAncestors( entry, ancestors, limit_ancestor_count, limit_ancestor_size, limit_descendant_count, limit_descendant_size, unused_error_string); } CFeeRate estimateSmartFee(int num_blocks, bool conservative, FeeCalculation* calc) override { if (!m_node.fee_estimator) return {}; return m_node.fee_estimator->estimateSmartFee(num_blocks, calc, conservative); } unsigned int estimateMaxBlocks() override { if (!m_node.fee_estimator) return 0; return m_node.fee_estimator->HighestTargetTracked(FeeEstimateHorizon::LONG_HALFLIFE); } CFeeRate mempoolMinFee() override { if (!m_node.mempool) return {}; return m_node.mempool->GetMinFee(gArgs.GetArg("-maxmempool", DEFAULT_MAX_MEMPOOL_SIZE) * 1000000); } CFeeRate relayMinFee() override { return ::minRelayTxFee; } CFeeRate relayIncrementalFee() override { return ::incrementalRelayFee; } CFeeRate relayDustFee() override { return ::dustRelayFee; } bool havePruned() override { LOCK(cs_main); return ::fHavePruned; } bool isReadyToBroadcast() override { return !::fImporting && !::fReindex && !isInitialBlockDownload(); } bool isInitialBlockDownload() override { assert(std::addressof(::ChainstateActive()) == std::addressof(m_node.chainman->ActiveChainstate())); return m_node.chainman->ActiveChainstate().IsInitialBlockDownload(); } bool shutdownRequested() override { return ShutdownRequested(); } int64_t getAdjustedTime() override { return GetAdjustedTime(); } void initMessage(const std::string& message) override { ::uiInterface.InitMessage(message); } void initWarning(const bilingual_str& message) override { InitWarning(message); } void initError(const bilingual_str& message) override { InitError(message); } void showProgress(const std::string& title, int progress, bool resume_possible) override { ::uiInterface.ShowProgress(title, progress, resume_possible); } std::unique_ptr handleNotifications(std::shared_ptr notifications) override { return std::make_unique(std::move(notifications)); } void waitForNotificationsIfTipChanged(const uint256& old_tip) override { if (!old_tip.IsNull()) { LOCK(::cs_main); const CChain& active = Assert(m_node.chainman)->ActiveChain(); if (old_tip == active.Tip()->GetBlockHash()) return; } SyncWithValidationInterfaceQueue(); } std::unique_ptr handleRpc(const CRPCCommand& command) override { return std::make_unique(command); } bool rpcEnableDeprecated(const std::string& method) override { return IsDeprecatedRPCEnabled(method); } void rpcRunLater(const std::string& name, std::function fn, int64_t seconds) override { RPCRunLater(name, std::move(fn), seconds); } int rpcSerializationFlags() override { return RPCSerializationFlags(); } util::SettingsValue getRwSetting(const std::string& name) override { util::SettingsValue result; gArgs.LockSettings([&](const util::Settings& settings) { if (const util::SettingsValue* value = util::FindKey(settings.rw_settings, name)) { result = *value; } }); return result; } bool updateRwSetting(const std::string& name, const util::SettingsValue& value) override { gArgs.LockSettings([&](util::Settings& settings) { if (value.isNull()) { settings.rw_settings.erase(name); } else { settings.rw_settings[name] = value; } }); return gArgs.WriteSettingsFile(); } void requestMempoolTransactions(Notifications& notifications) override { if (!m_node.mempool) return; LOCK2(::cs_main, m_node.mempool->cs); for (const CTxMemPoolEntry& entry : m_node.mempool->mapTx) { notifications.transactionAddedToMempool(entry.GetSharedTx(), 0 /* mempool_sequence */); } } NodeContext& m_node; }; } // namespace } // namespace node namespace interfaces { std::unique_ptr MakeNode(NodeContext* context) { return std::make_unique(context); } std::unique_ptr MakeChain(NodeContext& context) { return std::make_unique(context); } } // namespace interfaces