fix: fix some warnings by Coverity Scan in rpcMain.c (#14267)

src/rpc/src/rpcMain.c

@@ -361,8 +361,8 @@ void *rpcMallocCont(int contLen) {
 void rpcFreeCont(void *cont) {
   if (cont) {
     char *temp = ((char *)cont) - sizeof(SRpcHead) - sizeof(SRpcReqContext);
-    free(temp);
     tTrace("free mem: %p", temp);
+    free(temp);
   }
 }
 
@@ -573,8 +573,8 @@ void rpcCancelRequest(int64_t rid) {
 static void rpcFreeMsg(void *msg) {
   if ( msg ) {
     char *temp = (char *)msg - sizeof(SRpcReqContext);
-    free(temp);
     tTrace("free mem: %p", temp);
+    free(temp);
   }
 }
 
@@ -736,7 +736,7 @@ static SRpcConn *rpcAllocateServerConn(SRpcInfo *pRpc, SRecvInfo *pRecv) {
     memcpy(pConn->user, pHead->user, tListLen(pConn->user));
     pConn->pRpc = pRpc;
     pConn->sid = sid;
-    pConn->tranId = (uint16_t)(rand() & 0xFFFF);
+    pConn->tranId = (uint16_t)(random() & 0xFFFF);
     pConn->ownId = htonl(pConn->sid);
     pConn->linkUid = pHead->linkUid;
     if (pRpc->afp) {
@@ -1116,7 +1116,7 @@ static void *rpcProcessMsgFromPeer(SRecvInfo *pRecv) {
         if (pHead->msgType + 1 > 1 && pHead->msgType+1 < TSDB_MSG_TYPE_MAX) {
           tDebug("%s %p %p, %s is sent with error code:0x%x", pRpc->label, pConn, (void *)pHead->ahandle, taosMsg[pHead->msgType+1], code);
         } else {
-          tError("%s %p %p, %s is sent with error code:0x%x", pRpc->label, pConn, (void *)pHead->ahandle, taosMsg[pHead->msgType], code);
+          tError("%s %p %p, UnkownmsgType is sent with error code:0x%x", pRpc->label, pConn, (void *)pHead->ahandle, code);
         }     
       } 
     } else { // msg is passed to app only parsing is ok 
@@ -1172,6 +1172,7 @@ static void rpcProcessIncomingMsg(SRpcConn *pConn, SRpcHead *pHead, SRpcReqConte
           SRpcMsg rMsg = {.handle = rpcMsg.handle, .pCont = NULL, .contLen = 0};
           rpcSendResponse(&rMsg);
           rpcFreeCont(rpcMsg.pCont);
+          rpcFreeMsg(pHead);
           return;
         }
         break;