validation: return VerifyDBResult::INTERRUPTED if verification was interrupted

This means that the -verifydb RPC will now return false if it
cannot finish due to the node being shutdown.

Author: mzumsande

src/node/chainstate.cpp

@@ -193,6 +193,7 @@ ChainstateLoadResult VerifyLoadedChainstate(ChainstateManager& chainman, const C
                 options.check_blocks);
             switch (result) {
             case VerifyDBResult::SUCCESS:
+            case VerifyDBResult::INTERRUPTED:
                 break;
             case VerifyDBResult::CORRUPTED_BLOCK_DB:
                 return {ChainstateLoadStatus::FAILURE, _("Corrupted block database detected")};

src/validation.cpp

@@ -4146,7 +4146,7 @@ VerifyDBResult CVerifyDB::VerifyDB(
                 skipped_l3_checks = true;
             }
         }
-        if (ShutdownRequested()) return VerifyDBResult::SUCCESS;
+        if (ShutdownRequested()) return VerifyDBResult::INTERRUPTED;
     }
     if (pindexFailure) {
         LogPrintf("Verification error: coin database inconsistencies found (last %i blocks, %i good transactions before that)\n", chainstate.m_chain.Height() - pindexFailure->nHeight + 1, nGoodTransactions);
@@ -4179,7 +4179,7 @@ VerifyDBResult CVerifyDB::VerifyDB(
                 LogPrintf("Verification error: found unconnectable block at %d, hash=%s (%s)\n", pindex->nHeight, pindex->GetBlockHash().ToString(), state.ToString());
                 return VerifyDBResult::CORRUPTED_BLOCK_DB;
             }
-            if (ShutdownRequested()) return VerifyDBResult::SUCCESS;
+            if (ShutdownRequested()) return VerifyDBResult::INTERRUPTED;
         }
     }
 

src/validation.h

@@ -352,6 +352,7 @@ arith_uint256 CalculateHeadersWork(const std::vector<CBlockHeader>& headers);
 enum class VerifyDBResult {
     SUCCESS,
     CORRUPTED_BLOCK_DB,
+    INTERRUPTED,
 };
 
 /** RAII wrapper for VerifyDB: Verify consistency of the block and coin databases */