Initial implementation of abortrescan

src/wallet/rpcdump.cpp

@@ -144,6 +144,36 @@ UniValue convertpassphrase(const UniValue& params, bool fHelp, const CPubKey& my
     return ret;
 }
 
+UniValue abortrescan(const UniValue& params, bool fHelp, const CPubKey& mypk)
+{
+    if (!EnsureWalletIsAvailable(fHelp))
+        return NullUniValue;
+
+    if (fHelp || params.size() > 0)
+        throw runtime_error(
+            "abortrescan\n"
+            "\nAbort a currently running rescan.\n"
+            "\nUse 'getrescaninfo' to get rescan progress details.\n"
+            "\nReturns true if aborting rescan, false otherwise.\n"
+            "\nArguments: none\n"
+            "\nExamples:\n"
+            "\nAbort rescan :\n"
+            + HelpExampleCli("abortrescan","")
+            + "\nAs a JSON-RPC call\n"
+            + HelpExampleRpc("abortrescan","")
+        );
+    if(!pwalletMain->fRescanning) {
+        LogPrintf("%s: no rescan running\n",__func__);
+        return false;
+    }
+    if(pwalletMain->IsAbortingRescan()) {
+        LogPrintf("%s: already aborting current rescan\n",__func__);
+        return false;
+    }
+    pwalletMain->AbortRescan();
+    return true;
+}
+
 UniValue getrescaninfo(const UniValue& params, bool fHelp, const CPubKey& mypk)
 {
     if (!EnsureWalletIsAvailable(fHelp))

src/wallet/wallet.cpp

@@ -2778,6 +2778,19 @@ int CWallet::ScanForWalletTransactions(CBlockIndex* pindexStart, bool fUpdate)
         while (pindex)
         {
             pwalletMain->rescanHeight = pindex->GetHeight();
+            if(pwalletMain->fAbortRescan) {
+                //TODO: should we update witness caches?
+                LogPrintf("%s: Rescan aborted at block %d\n", pwalletMain->rescanHeight);
+                pwalletMain->fRescanning = false;
+                return ret;
+            }
+            if (ShutdownRequested()) {
+                //TODO: should we update witness caches?
+                LogPrintf("%s: Rescan interrupted by shutdown request at block %d\n", pwalletMain->rescanHeight);
+                pwalletMain->fRescanning = false;
+                return ret;
+            }
+
             if (pindex->GetHeight() % 100 == 0 && dProgressTip - dProgressStart > 0.0)
                 ShowProgress(_("Rescanning..."), std::max(1, std::min(99, (int)((Checkpoints::GuessVerificationProgress(chainParams.Checkpoints(), pindex, false) - dProgressStart) / (dProgressTip - dProgressStart) * 100))));
 

src/wallet/wallet.h

@@ -807,6 +807,13 @@ public:
     bool fSweepEnabled                = false;
     bool fSweepExternalEnabled        = false;
     bool fSweepRunning                = false;
+
+    std::atomic<bool> fAbortRescan{false};
+    // abort current rescan
+    void AbortRescan() { fAbortRescan = true; }
+    // Are we currently aborting a rescan?
+    bool IsAbortingRescan() const { return fAbortRescan; }
+
     // Are we currently rescanning?
     bool fRescanning                  = false;
     // Current height of our rescan