rpc: Avoid copies in JSONRPCReplyObj()

Change parameters from const references to values, so they can be moved into
the reply instead of copied. Also update callers to move instead of copy.

5 files changed, 16 insertions, 23 deletions

diff --git a/src/bitcoin-cli.cpp b/src/bitcoin-cli.cpp
index 45db7a9a66..3591f7248b 100644
--- a/src/bitcoin-cli.cpp
+++ b/src/bitcoin-cli.cpp
@@ -302,7 +302,7 @@ public:
         }
         addresses.pushKV("total", total);
         result.pushKV("addresses_known", addresses);
-        return JSONRPCReplyObj(result, NullUniValue, 1);
+        return JSONRPCReplyObj(std::move(result), NullUniValue, 1);
     }
 };
 
@@ -371,7 +371,7 @@ public:
         }
         result.pushKV("relayfee", batch[ID_NETWORKINFO]["result"]["relayfee"]);
         result.pushKV("warnings", batch[ID_NETWORKINFO]["result"]["warnings"]);
-        return JSONRPCReplyObj(result, NullUniValue, 1);
+        return JSONRPCReplyObj(std::move(result), NullUniValue, 1);
     }
 };
 
@@ -709,7 +709,7 @@ public:
         UniValue result(UniValue::VOBJ);
         result.pushKV("address", address_str);
         result.pushKV("blocks", reply.get_obj()["result"]);
-        return JSONRPCReplyObj(result, NullUniValue, 1);
+        return JSONRPCReplyObj(std::move(result), NullUniValue, 1);
     }
 protected:
     std::string address_str;
diff --git a/src/httprpc.cpp b/src/httprpc.cpp
index c72dbf10bc..aef20c24fc 100644
--- a/src/httprpc.cpp
+++ b/src/httprpc.cpp
@@ -73,7 +73,7 @@ static std::vector<std::vector<std::string>> g_rpcauth;
 static std::map<std::string, std::set<std::string>> g_rpc_whitelist;
 static bool g_rpc_whitelist_default = false;
 
-static void JSONErrorReply(HTTPRequest* req, const UniValue& objError, const UniValue& id)
+static void JSONErrorReply(HTTPRequest* req, UniValue objError, UniValue id)
 {
     // Send error reply from json-rpc error object
     int nStatus = HTTP_INTERNAL_SERVER_ERROR;
@@ -84,7 +84,7 @@ static void JSONErrorReply(HTTPRequest* req, const UniValue& objError, const Uni
     else if (code == RPC_METHOD_NOT_FOUND)
         nStatus = HTTP_NOT_FOUND;
 
-    std::string strReply = JSONRPCReply(NullUniValue, objError, id);
+    std::string strReply = JSONRPCReplyObj(NullUniValue, std::move(objError), std::move(id)).write() + "\n";
 
     req->WriteHeader("Content-Type", "application/json");
     req->WriteReply(nStatus, strReply);
@@ -203,7 +203,7 @@ static bool HTTPReq_JSONRPC(const std::any& context, HTTPRequest* req)
             UniValue result = tableRPC.execute(jreq);
 
             // Send reply
-            strReply = JSONRPCReply(result, NullUniValue, jreq.id);
+            strReply = JSONRPCReplyObj(std::move(result), NullUniValue, jreq.id).write() + "\n";
 
         // array of requests
         } else if (valRequest.isArray()) {
@@ -230,8 +230,8 @@ static bool HTTPReq_JSONRPC(const std::any& context, HTTPRequest* req)
 
         req->WriteHeader("Content-Type", "application/json");
         req->WriteReply(HTTP_OK, strReply);
-    } catch (const UniValue& objError) {
-        JSONErrorReply(req, objError, jreq.id);
+    } catch (UniValue& e) {
+        JSONErrorReply(req, std::move(e), jreq.id);
         return false;
     } catch (const std::exception& e) {
         JSONErrorReply(req, JSONRPCError(RPC_PARSE_ERROR, e.what()), jreq.id);
diff --git a/src/rpc/request.cpp b/src/rpc/request.cpp
index b7acd62ee3..12726ecc88 100644
--- a/src/rpc/request.cpp
+++ b/src/rpc/request.cpp
@@ -37,24 +37,18 @@ UniValue JSONRPCRequestObj(const std::string& strMethod, const UniValue& params,
     return request;
 }
 
-UniValue JSONRPCReplyObj(const UniValue& result, const UniValue& error, const UniValue& id)
+UniValue JSONRPCReplyObj(UniValue result, UniValue error, UniValue id)
 {
     UniValue reply(UniValue::VOBJ);
     if (!error.isNull())
         reply.pushKV("result", NullUniValue);
     else
-        reply.pushKV("result", result);
-    reply.pushKV("error", error);
-    reply.pushKV("id", id);
+        reply.pushKV("result", std::move(result));
+    reply.pushKV("error", std::move(error));
+    reply.pushKV("id", std::move(id));
     return reply;
 }
 
-std::string JSONRPCReply(const UniValue& result, const UniValue& error, const UniValue& id)
-{
-    UniValue reply = JSONRPCReplyObj(result, error, id);
-    return reply.write() + "\n";
-}
-
 UniValue JSONRPCError(int code, const std::string& message)
 {
     UniValue error(UniValue::VOBJ);
diff --git a/src/rpc/request.h b/src/rpc/request.h
index a682c58d96..116ebb8aac 100644
--- a/src/rpc/request.h
+++ b/src/rpc/request.h
@@ -12,8 +12,7 @@
 #include <univalue.h>
 
 UniValue JSONRPCRequestObj(const std::string& strMethod, const UniValue& params, const UniValue& id);
-UniValue JSONRPCReplyObj(const UniValue& result, const UniValue& error, const UniValue& id);
-std::string JSONRPCReply(const UniValue& result, const UniValue& error, const UniValue& id);
+UniValue JSONRPCReplyObj(UniValue result, UniValue error, UniValue id);
 UniValue JSONRPCError(int code, const std::string& message);
 
 /** Generate a new RPC authentication cookie and write it to disk */
diff --git a/src/rpc/server.cpp b/src/rpc/server.cpp
index 4883341522..fd18a7f9ec 100644
--- a/src/rpc/server.cpp
+++ b/src/rpc/server.cpp
@@ -366,11 +366,11 @@ static UniValue JSONRPCExecOne(JSONRPCRequest jreq, const UniValue& req)
         jreq.parse(req);
 
         UniValue result = tableRPC.execute(jreq);
-        rpc_result = JSONRPCReplyObj(result, NullUniValue, jreq.id);
+        rpc_result = JSONRPCReplyObj(std::move(result), NullUniValue, jreq.id);
     }
-    catch (const UniValue& objError)
+    catch (UniValue& e)
     {
-        rpc_result = JSONRPCReplyObj(NullUniValue, objError, jreq.id);
+        rpc_result = JSONRPCReplyObj(NullUniValue, std::move(e), jreq.id);
     }
     catch (const std::exception& e)
     {