From fa7fc5a8e0fcf9ca81e84b3631f18ae40502be60 Mon Sep 17 00:00:00 2001
From: MarcoFalke <falke.marco@gmail.com>
Date: Fri, 22 May 2020 15:38:48 -0400
Subject: [PATCH 1/2] rpc: factor out RpcInterruptionPoint from dumptxoutset

---
 src/rpc/blockchain.cpp | 4 +---
 src/rpc/server.cpp     | 7 ++++++-
 src/rpc/server.h       | 5 ++++-
 3 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/src/rpc/blockchain.cpp b/src/rpc/blockchain.cpp
index ac567e16ce..80ae35f48e 100644
--- a/src/rpc/blockchain.cpp
+++ b/src/rpc/blockchain.cpp
@@ -2329,9 +2329,7 @@ UniValue dumptxoutset(const JSONRPCRequest& request)
     unsigned int iter{0};
 
     while (pcursor->Valid()) {
-        if (iter % 5000 == 0 && !IsRPCRunning()) {
-            throw JSONRPCError(RPC_CLIENT_NOT_CONNECTED, "Shutting down");
-        }
+        if (iter % 5000 == 0) RpcInterruptionPoint();
         ++iter;
         if (pcursor->GetKey(key) && pcursor->GetValue(coin)) {
             afile << key;
diff --git a/src/rpc/server.cpp b/src/rpc/server.cpp
index 219979f095..99c649d15a 100644
--- a/src/rpc/server.cpp
+++ b/src/rpc/server.cpp
@@ -11,9 +11,9 @@
 #include <util/strencodings.h>
 #include <util/system.h>
 
-#include <boost/signals2/signal.hpp>
 #include <boost/algorithm/string/classification.hpp>
 #include <boost/algorithm/string/split.hpp>
+#include <boost/signals2/signal.hpp>
 
 #include <memory> // for unique_ptr
 #include <unordered_map>
@@ -309,6 +309,11 @@ bool IsRPCRunning()
     return g_rpc_running;
 }
 
+void RpcInterruptionPoint()
+{
+    if (!IsRPCRunning()) throw JSONRPCError(RPC_CLIENT_NOT_CONNECTED, "Shutting down");
+}
+
 void SetRPCWarmupStatus(const std::string& newStatus)
 {
     LOCK(cs_rpcWarmup);
diff --git a/src/rpc/server.h b/src/rpc/server.h
index c91bf1f613..d7a04ff6e8 100644
--- a/src/rpc/server.h
+++ b/src/rpc/server.h
@@ -9,10 +9,10 @@
 #include <amount.h>
 #include <rpc/request.h>
 
+#include <functional>
 #include <map>
 #include <stdint.h>
 #include <string>
-#include <functional>
 
 #include <univalue.h>
 
@@ -29,6 +29,9 @@ namespace RPCServer
 /** Query whether RPC is running */
 bool IsRPCRunning();
 
+/** Throw JSONRPCError if RPC is not running */
+void RpcInterruptionPoint();
+
 /**
  * Set the RPC warmup status.  When this is done, all RPC calls will error out
  * immediately with RPC_IN_WARMUP.

From fa756928c3f455943086051c5fe1d5bb09962248 Mon Sep 17 00:00:00 2001
From: MarcoFalke <falke.marco@gmail.com>
Date: Fri, 22 May 2020 16:09:34 -0400
Subject: [PATCH 2/2] rpc: Make gettxoutsetinfo/GetUTXOStats interruptible

Also, add interruption points to scantxoutset
---
 src/node/coinstats.cpp | 3 ++-
 src/node/coinstats.h   | 3 ++-
 src/rpc/blockchain.cpp | 5 +++--
 3 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/src/node/coinstats.cpp b/src/node/coinstats.cpp
index ec52a08ace..e3c4c828b6 100644
--- a/src/node/coinstats.cpp
+++ b/src/node/coinstats.cpp
@@ -33,7 +33,7 @@ static void ApplyStats(CCoinsStats &stats, CHashWriter& ss, const uint256& hash,
 }
 
 //! Calculate statistics about the unspent transaction output set
-bool GetUTXOStats(CCoinsView *view, CCoinsStats &stats)
+bool GetUTXOStats(CCoinsView* view, CCoinsStats& stats, const std::function<void()>& interruption_point)
 {
     stats = CCoinsStats();
     std::unique_ptr<CCoinsViewCursor> pcursor(view->Cursor());
@@ -49,6 +49,7 @@ bool GetUTXOStats(CCoinsView *view, CCoinsStats &stats)
     uint256 prevkey;
     std::map<uint32_t, Coin> outputs;
     while (pcursor->Valid()) {
+        interruption_point();
         COutPoint key;
         Coin coin;
         if (pcursor->GetKey(key) && pcursor->GetValue(coin)) {
diff --git a/src/node/coinstats.h b/src/node/coinstats.h
index a19af0fd1b..d9cdaa3036 100644
--- a/src/node/coinstats.h
+++ b/src/node/coinstats.h
@@ -10,6 +10,7 @@
 #include <uint256.h>
 
 #include <cstdint>
+#include <functional>
 
 class CCoinsView;
 
@@ -29,6 +30,6 @@ struct CCoinsStats
 };
 
 //! Calculate statistics about the unspent transaction output set
-bool GetUTXOStats(CCoinsView* view, CCoinsStats& stats);
+bool GetUTXOStats(CCoinsView* view, CCoinsStats& stats, const std::function<void()>& interruption_point = {});
 
 #endif // BITCOIN_NODE_COINSTATS_H
diff --git a/src/rpc/blockchain.cpp b/src/rpc/blockchain.cpp
index 80ae35f48e..e5c25681d0 100644
--- a/src/rpc/blockchain.cpp
+++ b/src/rpc/blockchain.cpp
@@ -990,7 +990,7 @@ static UniValue gettxoutsetinfo(const JSONRPCRequest& request)
     ::ChainstateActive().ForceFlushStateToDisk();
 
     CCoinsView* coins_view = WITH_LOCK(cs_main, return &ChainstateActive().CoinsDB());
-    if (GetUTXOStats(coins_view, stats)) {
+    if (GetUTXOStats(coins_view, stats, RpcInterruptionPoint)) {
         ret.pushKV("height", (int64_t)stats.nHeight);
         ret.pushKV("bestblock", stats.hashBlock.GetHex());
         ret.pushKV("transactions", (int64_t)stats.nTransactions);
@@ -1968,6 +1968,7 @@ bool FindScriptPubKey(std::atomic<int>& scan_progress, const std::atomic<bool>&
         Coin coin;
         if (!cursor->GetKey(key) || !cursor->GetValue(coin)) return false;
         if (++count % 8192 == 0) {
+            RpcInterruptionPoint();
             if (should_abort) {
                 // allow to abort the scan via the abort reference
                 return false;
@@ -2311,7 +2312,7 @@ UniValue dumptxoutset(const JSONRPCRequest& request)
 
         ::ChainstateActive().ForceFlushStateToDisk();
 
-        if (!GetUTXOStats(&::ChainstateActive().CoinsDB(), stats)) {
+        if (!GetUTXOStats(&::ChainstateActive().CoinsDB(), stats, RpcInterruptionPoint)) {
             throw JSONRPCError(RPC_INTERNAL_ERROR, "Unable to read UTXO set");
         }