Merge #15159: [RPC] Remove lookup to UTXO set from GetTransaction

04da9f4834 [RPC] Update getrawtransaction interface (Amiti Uttarwar)

Pull request description:

  - stop checking unspent UTXOs for a transaction when txindex is not enabled, as per conversation here: https://github.com/bitcoin/bitcoin/issues/3220#issuecomment-377458383
  - code contributed by sipa

Tree-SHA512: aa07353bccc14b81b7803992a25d076d6bc06d15ec7c1b85828dc10aea7e0498d9b49f71783e352ab8a14b0bb2010cfb7835de3dfd1bc6f2323f460449348e66

1 files changed, 5 insertions, 14 deletions

diff --git a/src/validation.cpp b/src/validation.cpp
index 6a26bf9baa..de9c0d96db 100644
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -1002,13 +1002,11 @@ bool AcceptToMemoryPool(CTxMemPool& pool, CValidationState &state, const CTransa
  * Return transaction in txOut, and if it was found inside a block, its hash is placed in hashBlock.
  * If blockIndex is provided, the transaction is fetched from the corresponding block.
  */
-bool GetTransaction(const uint256& hash, CTransactionRef& txOut, const Consensus::Params& consensusParams, uint256& hashBlock, bool fAllowSlow, CBlockIndex* blockIndex)
+bool GetTransaction(const uint256& hash, CTransactionRef& txOut, const Consensus::Params& consensusParams, uint256& hashBlock, const CBlockIndex* const block_index)
 {
-    CBlockIndex* pindexSlow = blockIndex;
-
     LOCK(cs_main);
 
-    if (!blockIndex) {
+    if (!block_index) {
         CTransactionRef ptx = mempool.get(hash);
         if (ptx) {
             txOut = ptx;
@@ -1018,20 +1016,13 @@ bool GetTransaction(const uint256& hash, CTransactionRef& txOut, const Consensus
         if (g_txindex) {
             return g_txindex->FindTx(hash, hashBlock, txOut);
         }
-
-        if (fAllowSlow) { // use coin database to locate block that contains transaction, and scan it
-            const Coin& coin = AccessByTxid(*pcoinsTip, hash);
-            if (!coin.IsSpent()) pindexSlow = chainActive[coin.nHeight];
-        }
-    }
-
-    if (pindexSlow) {
+    } else {
         CBlock block;
-        if (ReadBlockFromDisk(block, pindexSlow, consensusParams)) {
+        if (ReadBlockFromDisk(block, block_index, consensusParams)) {
             for (const auto& tx : block.vtx) {
                 if (tx->GetHash() == hash) {
                     txOut = tx;
-                    hashBlock = pindexSlow->GetBlockHash();
+                    hashBlock = block_index->GetBlockHash();
                     return true;
                 }
             }