wallet: Only fail rescan when blocks have actually been pruned

4 files changed, 35 insertions, 16 deletions

diff --git a/src/interfaces/chain.cpp b/src/interfaces/chain.cpp
index 839af650bb..1a60d4fd09 100644
--- a/src/interfaces/chain.cpp
+++ b/src/interfaces/chain.cpp
@@ -1,4 +1,4 @@
-// Copyright (c) 2018 The Bitcoin Core developers
+// Copyright (c) 2018-2019 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
@@ -325,7 +325,11 @@ public:
     CFeeRate relayMinFee() override { return ::minRelayTxFee; }
     CFeeRate relayIncrementalFee() override { return ::incrementalRelayFee; }
     CFeeRate relayDustFee() override { return ::dustRelayFee; }
-    bool getPruneMode() override { return ::fPruneMode; }
+    bool havePruned() override
+    {
+        LOCK(cs_main);
+        return ::fHavePruned;
+    }
     bool p2pEnabled() override { return g_connman != nullptr; }
     bool isReadyToBroadcast() override { return !::fImporting && !::fReindex && !IsInitialBlockDownload(); }
     bool isInitialBlockDownload() override { return IsInitialBlockDownload(); }
diff --git a/src/interfaces/chain.h b/src/interfaces/chain.h
index 7564ad26ac..550b2fe28e 100644
--- a/src/interfaces/chain.h
+++ b/src/interfaces/chain.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2018 The Bitcoin Core developers
+// Copyright (c) 2018-2019 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
@@ -207,8 +207,8 @@ public:
     //! Relay dust fee setting (-dustrelayfee), reflecting lowest rate it's economical to spend.
     virtual CFeeRate relayDustFee() = 0;
 
-    //! Check if pruning is enabled.
-    virtual bool getPruneMode() = 0;
+    //! Check if any block has been pruned.
+    virtual bool havePruned() = 0;
 
     //! Check if p2p enabled.
     virtual bool p2pEnabled() = 0;
diff --git a/src/wallet/rpcdump.cpp b/src/wallet/rpcdump.cpp
index c339e111ba..214f4bf503 100644
--- a/src/wallet/rpcdump.cpp
+++ b/src/wallet/rpcdump.cpp
@@ -157,8 +157,11 @@ UniValue importprivkey(const JSONRPCRequest& request)
         if (!request.params[2].isNull())
             fRescan = request.params[2].get_bool();
 
-        if (fRescan && pwallet->chain().getPruneMode()) {
-            throw JSONRPCError(RPC_WALLET_ERROR, "Rescan is disabled in pruned mode");
+        if (fRescan && pwallet->chain().havePruned()) {
+            // Exit early and print an error.
+            // If a block is pruned after this check, we will import the key(s),
+            // but fail the rescan with a generic error.
+            throw JSONRPCError(RPC_WALLET_ERROR, "Rescan is disabled when blocks are pruned");
         }
 
         if (fRescan && !reserver.reserve()) {
@@ -314,8 +317,11 @@ UniValue importaddress(const JSONRPCRequest& request)
     if (!request.params[2].isNull())
         fRescan = request.params[2].get_bool();
 
-    if (fRescan && pwallet->chain().getPruneMode()) {
-        throw JSONRPCError(RPC_WALLET_ERROR, "Rescan is disabled in pruned mode");
+    if (fRescan && pwallet->chain().havePruned()) {
+        // Exit early and print an error.
+        // If a block is pruned after this check, we will import the key(s),
+        // but fail the rescan with a generic error.
+        throw JSONRPCError(RPC_WALLET_ERROR, "Rescan is disabled when blocks are pruned");
     }
 
     WalletRescanReserver reserver(pwallet);
@@ -507,8 +513,11 @@ UniValue importpubkey(const JSONRPCRequest& request)
     if (!request.params[2].isNull())
         fRescan = request.params[2].get_bool();
 
-    if (fRescan && pwallet->chain().getPruneMode()) {
-        throw JSONRPCError(RPC_WALLET_ERROR, "Rescan is disabled in pruned mode");
+    if (fRescan && pwallet->chain().havePruned()) {
+        // Exit early and print an error.
+        // If a block is pruned after this check, we will import the key(s),
+        // but fail the rescan with a generic error.
+        throw JSONRPCError(RPC_WALLET_ERROR, "Rescan is disabled when blocks are pruned");
     }
 
     WalletRescanReserver reserver(pwallet);
@@ -573,7 +582,10 @@ UniValue importwallet(const JSONRPCRequest& request)
                 },
             }.ToString());
 
-    if (pwallet->chain().getPruneMode()) {
+    if (pwallet->chain().havePruned()) {
+        // Exit early and print an error.
+        // If a block is pruned after this check, we will import the key(s),
+        // but fail the rescan with a generic error.
         throw JSONRPCError(RPC_WALLET_ERROR, "Importing wallets is disabled in pruned mode");
     }
 
diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
index 8bbb47c093..1b8dbdb65a 100644
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -4219,10 +4219,13 @@ std::shared_ptr<CWallet> CWallet::CreateWalletFromFile(interfaces::Chain& chain,
 
     if (tip_height && *tip_height != rescan_height)
     {
-        //We can't rescan beyond non-pruned blocks, stop and throw an error
-        //this might happen if a user uses an old wallet within a pruned node
-        // or if he ran -disablewallet for a longer time, then decided to re-enable
-        if (chain.getPruneMode()) {
+        // We can't rescan beyond non-pruned blocks, stop and throw an error.
+        // This might happen if a user uses an old wallet within a pruned node
+        // or if they ran -disablewallet for a longer time, then decided to re-enable
+        if (chain.havePruned()) {
+            // Exit early and print an error.
+            // If a block is pruned after this check, we will load the wallet,
+            // but fail the rescan with a generic error.
             int block_height = *tip_height;
             while (block_height > 0 && locked_chain->haveBlockOnDisk(block_height - 1) && rescan_height != block_height) {
                 --block_height;