1.1.0

src/node/README.md

@@ -0,0 +1,22 @@
+# src/node/
+
+The [`src/node/`](./) directory contains code that needs to access node state
+(state in `CChain`, `CBlockIndex`, `CCoinsView`, `CTxMemPool`, and similar
+classes).
+
+Code in [`src/node/`](./) is meant to be segregated from code in
+[`src/wallet/`](../wallet/) and [`src/qt/`](../qt/), to ensure wallet and GUI
+code changes don't interfere with node operation, to allow wallet and GUI code
+to run in separate processes, and to perhaps eventually allow wallet and GUI
+code to be maintained in separate source repositories.
+
+As a rule of thumb, code in one of the [`src/node/`](./),
+[`src/wallet/`](../wallet/), or [`src/qt/`](../qt/) directories should avoid
+calling code in the other directories directly, and only invoke it indirectly
+through the more limited [`src/interfaces/`](../interfaces/) classes.
+
+The [`src/node/`](./) directory is a new directory introduced in
+[#14978](https://github.com/palladium/palladium/pull/14978) and at the moment is
+sparsely populated. Eventually more substantial files like
+[`src/validation.cpp`](../validation.cpp) and
+[`src/txmempool.cpp`](../txmempool.cpp) might be moved there.

src/node/coin.cpp

@@ -0,0 +1,23 @@
+// Copyright (c) 2019 The Palladium Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include <node/coin.h>
+
+#include <node/context.h>
+#include <txmempool.h>
+#include <validation.h>
+
+void FindCoins(const NodeContext& node, std::map<COutPoint, Coin>& coins)
+{
+    assert(node.mempool);
+    LOCK2(cs_main, node.mempool->cs);
+    CCoinsViewCache& chain_view = ::ChainstateActive().CoinsTip();
+    CCoinsViewMemPool mempool_view(&chain_view, *node.mempool);
+    for (auto& coin : coins) {
+        if (!mempool_view.GetCoin(coin.first, coin.second)) {
+            // Either the coin is not in the CCoinsViewCache or is spent. Clear it.
+            coin.second.Clear();
+        }
+    }
+}

src/node/coin.h

@@ -0,0 +1,24 @@
+// Copyright (c) 2019 The Palladium Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef PALLADIUM_NODE_COIN_H
+#define PALLADIUM_NODE_COIN_H
+
+#include <map>
+
+class COutPoint;
+class Coin;
+struct NodeContext;
+
+/**
+ * Look up unspent output information. Returns coins in the mempool and in the
+ * current chain UTXO set. Iterates through all the keys in the map and
+ * populates the values.
+ *
+ * @param[in] node The node context to use for lookup
+ * @param[in,out] coins map to fill
+ */
+void FindCoins(const NodeContext& node, std::map<COutPoint, Coin>& coins);
+
+#endif // PALLADIUM_NODE_COIN_H

src/node/coinstats.cpp

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+// Copyright (c) 2010 Satoshi Nakamoto
+// Copyright (c) 2009-2019 The Palladium Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include <node/coinstats.h>
+
+#include <coins.h>
+#include <hash.h>
+#include <serialize.h>
+#include <validation.h>
+#include <uint256.h>
+#include <util/system.h>
+
+#include <map>
+
+static void ApplyStats(CCoinsStats &stats, CHashWriter& ss, const uint256& hash, const std::map<uint32_t, Coin>& outputs)
+{
+    assert(!outputs.empty());
+    ss << hash;
+    ss << VARINT(outputs.begin()->second.nHeight * 2 + outputs.begin()->second.fCoinBase ? 1u : 0u);
+    stats.nTransactions++;
+    for (const auto& output : outputs) {
+        ss << VARINT(output.first + 1);
+        ss << output.second.out.scriptPubKey;
+        ss << VARINT_MODE(output.second.out.nValue, VarIntMode::NONNEGATIVE_SIGNED);
+        stats.nTransactionOutputs++;
+        stats.nTotalAmount += output.second.out.nValue;
+        stats.nBogoSize += 32 /* txid */ + 4 /* vout index */ + 4 /* height + coinbase */ + 8 /* amount */ +
+                           2 /* scriptPubKey len */ + output.second.out.scriptPubKey.size() /* scriptPubKey */;
+    }
+    ss << VARINT(0u);
+}
+
+//! Calculate statistics about the unspent transaction output set
+bool GetUTXOStats(CCoinsView *view, CCoinsStats &stats)
+{
+    stats = CCoinsStats();
+    std::unique_ptr<CCoinsViewCursor> pcursor(view->Cursor());
+    assert(pcursor);
+
+    CHashWriter ss(SER_GETHASH, PROTOCOL_VERSION);
+    stats.hashBlock = pcursor->GetBestBlock();
+    {
+        LOCK(cs_main);
+        stats.nHeight = LookupBlockIndex(stats.hashBlock)->nHeight;
+    }
+    ss << stats.hashBlock;
+    uint256 prevkey;
+    std::map<uint32_t, Coin> outputs;
+    while (pcursor->Valid()) {
+        COutPoint key;
+        Coin coin;
+        if (pcursor->GetKey(key) && pcursor->GetValue(coin)) {
+            if (!outputs.empty() && key.hash != prevkey) {
+                ApplyStats(stats, ss, prevkey, outputs);
+                outputs.clear();
+            }
+            prevkey = key.hash;
+            outputs[key.n] = std::move(coin);
+            stats.coins_count++;
+        } else {
+            return error("%s: unable to read value", __func__);
+        }
+        pcursor->Next();
+    }
+    if (!outputs.empty()) {
+        ApplyStats(stats, ss, prevkey, outputs);
+    }
+    stats.hashSerialized = ss.GetHash();
+    stats.nDiskSize = view->EstimateSize();
+    return true;
+}

src/node/coinstats.h

@@ -0,0 +1,34 @@
+// Copyright (c) 2010 Satoshi Nakamoto
+// Copyright (c) 2009-2019 The Palladium Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef PALLADIUM_NODE_COINSTATS_H
+#define PALLADIUM_NODE_COINSTATS_H
+
+#include <amount.h>
+#include <uint256.h>
+
+#include <cstdint>
+
+class CCoinsView;
+
+struct CCoinsStats
+{
+    int nHeight{0};
+    uint256 hashBlock{};
+    uint64_t nTransactions{0};
+    uint64_t nTransactionOutputs{0};
+    uint64_t nBogoSize{0};
+    uint256 hashSerialized{};
+    uint64_t nDiskSize{0};
+    CAmount nTotalAmount{0};
+
+    //! The number of coins contained.
+    uint64_t coins_count{0};
+};
+
+//! Calculate statistics about the unspent transaction output set
+bool GetUTXOStats(CCoinsView* view, CCoinsStats& stats);
+
+#endif // PALLADIUM_NODE_COINSTATS_H

src/node/context.cpp

@@ -0,0 +1,14 @@
+// Copyright (c) 2019 The Palladium Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include <node/context.h>
+
+#include <banman.h>
+#include <interfaces/chain.h>
+#include <net.h>
+#include <net_processing.h>
+#include <scheduler.h>
+
+NodeContext::NodeContext() {}
+NodeContext::~NodeContext() {}

src/node/context.h

@@ -0,0 +1,47 @@
+// Copyright (c) 2019 The Palladium Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef PALLADIUM_NODE_CONTEXT_H
+#define PALLADIUM_NODE_CONTEXT_H
+
+#include <memory>
+#include <vector>
+
+class BanMan;
+class CConnman;
+class CScheduler;
+class CTxMemPool;
+class PeerLogicValidation;
+namespace interfaces {
+class Chain;
+class ChainClient;
+} // namespace interfaces
+
+//! NodeContext struct containing references to chain state and connection
+//! state.
+//!
+//! This is used by init, rpc, and test code to pass object references around
+//! without needing to declare the same variables and parameters repeatedly, or
+//! to use globals. More variables could be added to this struct (particularly
+//! references to validation objects) to eliminate use of globals
+//! and make code more modular and testable. The struct isn't intended to have
+//! any member functions. It should just be a collection of references that can
+//! be used without pulling in unwanted dependencies or functionality.
+struct NodeContext {
+    std::unique_ptr<CConnman> connman;
+    CTxMemPool* mempool{nullptr}; // Currently a raw pointer because the memory is not managed by this struct
+    std::unique_ptr<PeerLogicValidation> peer_logic;
+    std::unique_ptr<BanMan> banman;
+    std::unique_ptr<interfaces::Chain> chain;
+    std::vector<std::unique_ptr<interfaces::ChainClient>> chain_clients;
+    std::unique_ptr<CScheduler> scheduler;
+
+    //! Declare default constructor and destructor that are not inline, so code
+    //! instantiating the NodeContext struct doesn't need to #include class
+    //! definitions for all the unique_ptr members.
+    NodeContext();
+    ~NodeContext();
+};
+
+#endif // PALLADIUM_NODE_CONTEXT_H

src/node/psbt.cpp

@@ -0,0 +1,147 @@
+// Copyright (c) 2009-2019 The Palladium Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include <amount.h>
+#include <coins.h>
+#include <consensus/tx_verify.h>
+#include <node/psbt.h>
+#include <policy/policy.h>
+#include <policy/settings.h>
+#include <tinyformat.h>
+
+#include <numeric>
+
+PSBTAnalysis AnalyzePSBT(PartiallySignedTransaction psbtx)
+{
+    // Go through each input and build status
+    PSBTAnalysis result;
+
+    bool calc_fee = true;
+
+    CAmount in_amt = 0;
+
+    result.inputs.resize(psbtx.tx->vin.size());
+
+    for (unsigned int i = 0; i < psbtx.tx->vin.size(); ++i) {
+        PSBTInput& input = psbtx.inputs[i];
+        PSBTInputAnalysis& input_analysis = result.inputs[i];
+
+        // We set next role here and ratchet backwards as required
+        input_analysis.next = PSBTRole::EXTRACTOR;
+
+        // Check for a UTXO
+        CTxOut utxo;
+        if (psbtx.GetInputUTXO(utxo, i)) {
+            if (!MoneyRange(utxo.nValue) || !MoneyRange(in_amt + utxo.nValue)) {
+                result.SetInvalid(strprintf("PSBT is not valid. Input %u has invalid value", i));
+                return result;
+            }
+            in_amt += utxo.nValue;
+            input_analysis.has_utxo = true;
+        } else {
+            if (input.non_witness_utxo && psbtx.tx->vin[i].prevout.n >= input.non_witness_utxo->vout.size()) {
+                result.SetInvalid(strprintf("PSBT is not valid. Input %u specifies invalid prevout", i));
+                return result;
+            }
+            input_analysis.has_utxo = false;
+            input_analysis.is_final = false;
+            input_analysis.next = PSBTRole::UPDATER;
+            calc_fee = false;
+        }
+
+        if (!utxo.IsNull() && utxo.scriptPubKey.IsUnspendable()) {
+            result.SetInvalid(strprintf("PSBT is not valid. Input %u spends unspendable output", i));
+            return result;
+        }
+
+        // Check if it is final
+        if (!utxo.IsNull() && !PSBTInputSigned(input)) {
+            input_analysis.is_final = false;
+
+            // Figure out what is missing
+            SignatureData outdata;
+            bool complete = SignPSBTInput(DUMMY_SIGNING_PROVIDER, psbtx, i, 1, &outdata);
+
+            // Things are missing
+            if (!complete) {
+                input_analysis.missing_pubkeys = outdata.missing_pubkeys;
+                input_analysis.missing_redeem_script = outdata.missing_redeem_script;
+                input_analysis.missing_witness_script = outdata.missing_witness_script;
+                input_analysis.missing_sigs = outdata.missing_sigs;
+
+                // If we are only missing signatures and nothing else, then next is signer
+                if (outdata.missing_pubkeys.empty() && outdata.missing_redeem_script.IsNull() && outdata.missing_witness_script.IsNull() && !outdata.missing_sigs.empty()) {
+                    input_analysis.next = PSBTRole::SIGNER;
+                } else {
+                    input_analysis.next = PSBTRole::UPDATER;
+                }
+            } else {
+                input_analysis.next = PSBTRole::FINALIZER;
+            }
+        } else if (!utxo.IsNull()){
+            input_analysis.is_final = true;
+        }
+    }
+
+    // Calculate next role for PSBT by grabbing "minimum" PSBTInput next role
+    result.next = PSBTRole::EXTRACTOR;
+    for (unsigned int i = 0; i < psbtx.tx->vin.size(); ++i) {
+        PSBTInputAnalysis& input_analysis = result.inputs[i];
+        result.next = std::min(result.next, input_analysis.next);
+    }
+    assert(result.next > PSBTRole::CREATOR);
+
+    if (calc_fee) {
+        // Get the output amount
+        CAmount out_amt = std::accumulate(psbtx.tx->vout.begin(), psbtx.tx->vout.end(), CAmount(0),
+            [](CAmount a, const CTxOut& b) {
+                if (!MoneyRange(a) || !MoneyRange(b.nValue) || !MoneyRange(a + b.nValue)) {
+                    return CAmount(-1);
+                }
+                return a += b.nValue;
+            }
+        );
+        if (!MoneyRange(out_amt)) {
+            result.SetInvalid(strprintf("PSBT is not valid. Output amount invalid"));
+            return result;
+        }
+
+        // Get the fee
+        CAmount fee = in_amt - out_amt;
+        result.fee = fee;
+
+        // Estimate the size
+        CMutableTransaction mtx(*psbtx.tx);
+        CCoinsView view_dummy;
+        CCoinsViewCache view(&view_dummy);
+        bool success = true;
+
+        for (unsigned int i = 0; i < psbtx.tx->vin.size(); ++i) {
+            PSBTInput& input = psbtx.inputs[i];
+            Coin newcoin;
+
+            if (!SignPSBTInput(DUMMY_SIGNING_PROVIDER, psbtx, i, 1, nullptr, true) || !psbtx.GetInputUTXO(newcoin.out, i)) {
+                success = false;
+                break;
+            } else {
+                mtx.vin[i].scriptSig = input.final_script_sig;
+                mtx.vin[i].scriptWitness = input.final_script_witness;
+                newcoin.nHeight = 1;
+                view.AddCoin(psbtx.tx->vin[i].prevout, std::move(newcoin), true);
+            }
+        }
+
+        if (success) {
+            CTransaction ctx = CTransaction(mtx);
+            size_t size = GetVirtualTransactionSize(ctx, GetTransactionSigOpCost(ctx, view, STANDARD_SCRIPT_VERIFY_FLAGS));
+            result.estimated_vsize = size;
+            // Estimate fee rate
+            CFeeRate feerate(fee, size);
+            result.estimated_feerate = feerate;
+        }
+
+    }
+
+    return result;
+}

src/node/psbt.h

@@ -0,0 +1,54 @@
+// Copyright (c) 2009-2019 The Palladium Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef PALLADIUM_NODE_PSBT_H
+#define PALLADIUM_NODE_PSBT_H
+
+#include <psbt.h>
+
+/**
+ * Holds an analysis of one input from a PSBT
+ */
+struct PSBTInputAnalysis {
+    bool has_utxo; //!< Whether we have UTXO information for this input
+    bool is_final; //!< Whether the input has all required information including signatures
+    PSBTRole next; //!< Which of the BIP 174 roles needs to handle this input next
+
+    std::vector<CKeyID> missing_pubkeys; //!< Pubkeys whose BIP32 derivation path is missing
+    std::vector<CKeyID> missing_sigs;    //!< Pubkeys whose signatures are missing
+    uint160 missing_redeem_script;       //!< Hash160 of redeem script, if missing
+    uint256 missing_witness_script;      //!< SHA256 of witness script, if missing
+};
+
+/**
+ * Holds the results of AnalyzePSBT (miscellaneous information about a PSBT)
+ */
+struct PSBTAnalysis {
+    Optional<size_t> estimated_vsize;      //!< Estimated weight of the transaction
+    Optional<CFeeRate> estimated_feerate;  //!< Estimated feerate (fee / weight) of the transaction
+    Optional<CAmount> fee;                 //!< Amount of fee being paid by the transaction
+    std::vector<PSBTInputAnalysis> inputs; //!< More information about the individual inputs of the transaction
+    PSBTRole next;                         //!< Which of the BIP 174 roles needs to handle the transaction next
+    std::string error;                     //!< Error message
+
+    void SetInvalid(std::string err_msg)
+    {
+        estimated_vsize = nullopt;
+        estimated_feerate = nullopt;
+        fee = nullopt;
+        inputs.clear();
+        next = PSBTRole::CREATOR;
+        error = err_msg;
+    }
+};
+
+/**
+ * Provides helpful miscellaneous information about where a PSBT is in the signing workflow.
+ *
+ * @param[in] psbtx the PSBT to analyze
+ * @return A PSBTAnalysis with information about the provided PSBT.
+ */
+PSBTAnalysis AnalyzePSBT(PartiallySignedTransaction psbtx);
+
+#endif // PALLADIUM_NODE_PSBT_H

src/node/transaction.cpp

@@ -0,0 +1,85 @@
+// Copyright (c) 2010 Satoshi Nakamoto
+// Copyright (c) 2009-2019 The Palladium Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include <consensus/validation.h>
+#include <net.h>
+#include <net_processing.h>
+#include <node/context.h>
+#include <validation.h>
+#include <validationinterface.h>
+#include <node/transaction.h>
+
+#include <future>
+
+TransactionError BroadcastTransaction(NodeContext& node, const CTransactionRef tx, std::string& err_string, const CAmount& max_tx_fee, bool relay, bool wait_callback)
+{
+    // BroadcastTransaction can be called by either sendrawtransaction RPC or wallet RPCs.
+    // node.connman is assigned both before chain clients and before RPC server is accepting calls,
+    // and reset after chain clients and RPC sever are stopped. node.connman should never be null here.
+    assert(node.connman);
+    assert(node.mempool);
+    std::promise<void> promise;
+    uint256 hashTx = tx->GetHash();
+    bool callback_set = false;
+
+    { // cs_main scope
+    LOCK(cs_main);
+    // If the transaction is already confirmed in the chain, don't do anything
+    // and return early.
+    CCoinsViewCache &view = ::ChainstateActive().CoinsTip();
+    for (size_t o = 0; o < tx->vout.size(); o++) {
+        const Coin& existingCoin = view.AccessCoin(COutPoint(hashTx, o));
+        // IsSpent doesn't mean the coin is spent, it means the output doesn't exist.
+        // So if the output does exist, then this transaction exists in the chain.
+        if (!existingCoin.IsSpent()) return TransactionError::ALREADY_IN_CHAIN;
+    }
+    if (!node.mempool->exists(hashTx)) {
+        // Transaction is not already in the mempool. Submit it.
+        TxValidationState state;
+        if (!AcceptToMemoryPool(*node.mempool, state, std::move(tx),
+                nullptr /* plTxnReplaced */, false /* bypass_limits */, max_tx_fee)) {
+            err_string = state.ToString();
+            if (state.IsInvalid()) {
+                if (state.GetResult() == TxValidationResult::TX_MISSING_INPUTS) {
+                    return TransactionError::MISSING_INPUTS;
+                }
+                return TransactionError::MEMPOOL_REJECTED;
+            } else {
+                return TransactionError::MEMPOOL_ERROR;
+            }
+        }
+
+        // Transaction was accepted to the mempool.
+
+        if (wait_callback) {
+            // For transactions broadcast from outside the wallet, make sure
+            // that the wallet has been notified of the transaction before
+            // continuing.
+            //
+            // This prevents a race where a user might call sendrawtransaction
+            // with a transaction to/from their wallet, immediately call some
+            // wallet RPC, and get a stale result because callbacks have not
+            // yet been processed.
+            CallFunctionInValidationInterfaceQueue([&promise] {
+                promise.set_value();
+            });
+            callback_set = true;
+        }
+    }
+
+    } // cs_main
+
+    if (callback_set) {
+        // Wait until Validation Interface clients have been notified of the
+        // transaction entering the mempool.
+        promise.get_future().wait();
+    }
+
+    if (relay) {
+        RelayTransaction(hashTx, *node.connman);
+    }
+
+    return TransactionError::OK;
+}

src/node/transaction.h

@@ -0,0 +1,33 @@
+// Copyright (c) 2017-2019 The Palladium Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef PALLADIUM_NODE_TRANSACTION_H
+#define PALLADIUM_NODE_TRANSACTION_H
+
+#include <attributes.h>
+#include <primitives/transaction.h>
+#include <util/error.h>
+
+struct NodeContext;
+
+/**
+ * Submit a transaction to the mempool and (optionally) relay it to all P2P peers.
+ *
+ * Mempool submission can be synchronous (will await mempool entry notification
+ * over the CValidationInterface) or asynchronous (will submit and not wait for
+ * notification), depending on the value of wait_callback. wait_callback MUST
+ * NOT be set while cs_main, cs_mempool or cs_wallet are held to avoid
+ * deadlock.
+ *
+ * @param[in]  node reference to node context
+ * @param[in]  tx the transaction to broadcast
+ * @param[out] err_string reference to std::string to fill with error string if available
+ * @param[in]  max_tx_fee reject txs with fees higher than this (if 0, accept any fee)
+ * @param[in]  relay flag if both mempool insertion and p2p relay are requested
+ * @param[in]  wait_callback wait until callbacks have been processed to avoid stale result due to a sequentially RPC.
+ * return error
+ */
+NODISCARD TransactionError BroadcastTransaction(NodeContext& node, CTransactionRef tx, std::string& err_string, const CAmount& max_tx_fee, bool relay, bool wait_callback);
+
+#endif // PALLADIUM_NODE_TRANSACTION_H

src/node/utxo_snapshot.h

@@ -0,0 +1,50 @@
+// Copyright (c) 2009-2010 Satoshi Nakamoto
+// Copyright (c) 2009-2019 The Palladium Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef PALLADIUM_NODE_UTXO_SNAPSHOT_H
+#define PALLADIUM_NODE_UTXO_SNAPSHOT_H
+
+#include <uint256.h>
+#include <serialize.h>
+
+//! Metadata describing a serialized version of a UTXO set from which an
+//! assumeutxo CChainState can be constructed.
+class SnapshotMetadata
+{
+public:
+    //! The hash of the block that reflects the tip of the chain for the
+    //! UTXO set contained in this snapshot.
+    uint256 m_base_blockhash;
+
+    //! The number of coins in the UTXO set contained in this snapshot. Used
+    //! during snapshot load to estimate progress of UTXO set reconstruction.
+    uint64_t m_coins_count = 0;
+
+    //! Necessary to "fake" the base nChainTx so that we can estimate progress during
+    //! initial block download for the assumeutxo chainstate.
+    unsigned int m_nchaintx = 0;
+
+    SnapshotMetadata() { }
+    SnapshotMetadata(
+        const uint256& base_blockhash,
+        uint64_t coins_count,
+        unsigned int nchaintx) :
+            m_base_blockhash(base_blockhash),
+            m_coins_count(coins_count),
+            m_nchaintx(nchaintx) { }
+
+    ADD_SERIALIZE_METHODS;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action)
+    {
+        READWRITE(m_base_blockhash);
+        READWRITE(m_coins_count);
+        READWRITE(m_nchaintx);
+    }
+
+};
+
+#endif // PALLADIUM_NODE_UTXO_SNAPSHOT_H