cassandra: Add wrapper functions in preparation for following commits

No functional changes. Shrinks the following commits.

src/lib-sql/driver-cassandra.c

@@ -699,12 +699,37 @@ static void driver_cassandra_result_unlink(struct cassandra_db *db,
 	i_unreached();
 }
 
+static void driver_cassandra_log_result(struct cassandra_result *result,
+					long long reply_usecs)
+{
+	struct cassandra_db *db = (struct cassandra_db *)result->api.db;
+	struct timeval now;
+	const char *str;
+
+	if (db->log_level < CASS_LOG_DEBUG && !db->debug_queries &&
+	    reply_usecs/1000 < db->warn_timeout_msecs)
+		return;
+
+	if (gettimeofday(&now, NULL) < 0)
+		i_fatal("gettimeofday() failed: %m");
+	str = t_strdup_printf(
+		"cassandra: Finished query '%s' (%u rows, %lld+%lld us): %s",
+		result->query, result->row_count, reply_usecs,
+		timeval_diff_usecs(&now, &result->finish_time),
+		result->error != NULL ? result->error : "success");
+
+	if (reply_usecs/1000 >= db->warn_timeout_msecs) {
+		db->counters[CASSANDRA_COUNTER_TYPE_QUERY_SLOW]++;
+		i_warning("%s", str);
+	} else {
+		i_debug("%s", str);
+	}
+}
+
 static void driver_cassandra_result_free(struct sql_result *_result)
 {
 	struct cassandra_db *db = (struct cassandra_db *)_result->db;
         struct cassandra_result *result = (struct cassandra_result *)_result;
-	struct timeval now;
-	const char *str;
 	long long reply_usecs;
 
 	i_assert(!result->api.callback);
@@ -714,22 +739,7 @@ static void driver_cassandra_result_free(struct sql_result *_result)
 		db->sync_result = NULL;
 
 	reply_usecs = timeval_diff_usecs(&result->finish_time, &result->start_time);
-	if (db->log_level >= CASS_LOG_DEBUG || db->debug_queries ||
-	    reply_usecs/1000 >= db->warn_timeout_msecs) {
-		if (gettimeofday(&now, NULL) < 0)
-			i_fatal("gettimeofday() failed: %m");
-		str = t_strdup_printf(
-			"cassandra: Finished query '%s' (%u rows, %lld+%lld us): %s",
-			result->query, result->row_count, reply_usecs,
-			timeval_diff_usecs(&now, &result->finish_time),
-			result->error != NULL ? result->error : "success");
-
-		if (reply_usecs/1000 >= db->warn_timeout_msecs) {
-			db->counters[CASSANDRA_COUNTER_TYPE_QUERY_SLOW]++;
-			i_warning("%s", str);
-		} else
-			i_debug("%s", str);
-	}
+	driver_cassandra_log_result(result, reply_usecs);
 
 	if (result->result != NULL)
 		cass_result_free(result->result);
@@ -879,19 +889,24 @@ static void query_callback(CassFuture *future, void *context)
 	result_finish(result);
 }
 
-static void driver_cassandra_result_send_query(struct cassandra_result *result)
+static void driver_cassandra_init_statement(struct cassandra_result *result)
 {
-	struct cassandra_db *db = (struct cassandra_db *)result->api.db;
-	CassFuture *future;
-
-	db->counters[CASSANDRA_COUNTER_TYPE_QUERY_SENT]++;
-
 	result->statement = cass_statement_new(result->query, 0);
 	cass_statement_set_consistency(result->statement, result->consistency);
 
 #ifdef HAVE_CASSANDRA_SPECULATIVE_POLICY
 	cass_statement_set_is_idempotent(result->statement, cass_true);
 #endif
+}
+
+static void driver_cassandra_result_send_query(struct cassandra_result *result)
+{
+	struct cassandra_db *db = (struct cassandra_db *)result->api.db;
+	CassFuture *future;
+
+	db->counters[CASSANDRA_COUNTER_TYPE_QUERY_SENT]++;
+	driver_cassandra_init_statement(result);
+
 	future = cass_session_execute(db->session, result->statement);
 	driver_cassandra_set_callback(future, db, query_callback, result);
 }
@@ -990,24 +1005,35 @@ static void exec_callback(struct sql_result *_result ATTR_UNUSED,
 {
 }
 
-static void
-driver_cassandra_query_full(struct sql_db *_db, const char *query,
+static struct cassandra_result *
+driver_cassandra_query_init(struct cassandra_db *db, const char *query,
 			    enum cassandra_query_type query_type,
 			    sql_query_callback_t *callback, void *context)
 {
-        struct cassandra_db *db = (struct cassandra_db *)_db;
 	struct cassandra_result *result;
 
 	result = i_new(struct cassandra_result, 1);
 	result->api = driver_cassandra_result;
-	result->api.db = _db;
+	result->api.db = &db->api;
 	result->api.refcount = 1;
 	result->callback = callback;
 	result->context = context;
 	result->query_type = query_type;
 	result->query = i_strdup(query);
 	array_append(&db->results, &result, 1);
+	return result;
+}
+
+static void
+driver_cassandra_query_full(struct sql_db *_db, const char *query,
+			    enum cassandra_query_type query_type,
+			    sql_query_callback_t *callback, void *context)
+{
+	struct cassandra_db *db = (struct cassandra_db *)_db;
+	struct cassandra_result *result;
 
+	result = driver_cassandra_query_init(db, query, query_type,
+					     callback, context);
 	(void)driver_cassandra_send_query(result);
 }