rpc: move UniValue in blockToJSON

willcl-ark · willcl-ark · commit b77bad309e92 · 2024-05-13T14:30:44.000+01:00
Without explicitly declaring the move, these UniValues get copied,
causing increased memory usage. Fix this by explicitly moving the
UniValue objects.

Used by `rest_block` and `getblock` RPC.
diff --git a/src/rpc/blockchain.cpp b/src/rpc/blockchain.cpp
@@ -188,12 +188,12 @@ UniValue blockToJSON(BlockManager& blockman, const CBlock& block, const CBlockIn
                 const CTxUndo* txundo = (have_undo && i > 0) ? &blockUndo.vtxundo.at(i - 1) : nullptr;
                 UniValue objTx(UniValue::VOBJ);
                 TxToUniv(*tx, /*block_hash=*/uint256(), /*entry=*/objTx, /*include_hex=*/true, txundo, verbosity);
-                txs.push_back(objTx);
+                txs.push_back(std::move(objTx));
             }
             break;
     }
 
-    result.pushKV("tx", txs);
+    result.pushKV("tx", std::move(txs));
 
     return result;
 }

Original file line number	Diff line number	Diff line change
`@@ -188,12 +188,12 @@ UniValue blockToJSON(BlockManager& blockman, const CBlock& block, const CBlockIn`
`188`	`188`	`const CTxUndo* txundo = (have_undo && i > 0) ? &blockUndo.vtxundo.at(i - 1) : nullptr;`
`189`	`189`	`UniValue objTx(UniValue::VOBJ);`
`190`	`190`	`TxToUniv(tx, /block_hash=/uint256(), /entry=/objTx, /include_hex=*/true, txundo, verbosity);`
`191`		`- txs.push_back(objTx);`
	`191`	`+ txs.push_back(std::move(objTx));`
`192`	`192`	`}`
`193`	`193`	`break;`
`194`	`194`	`}`
`195`	`195`
`196`		`- result.pushKV("tx", txs);`
	`196`	`+ result.pushKV("tx", std::move(txs));`
`197`	`197`
`198`	`198`	`return result;`
`199`	`199`	`}`