1 files changed, 16 insertions, 11 deletions

diff --git a/src/plugins/influxdb-writer.c b/src/plugins/influxdb-writer.c
index a7ce8fc..e22c2bd 100644
--- a/src/plugins/influxdb-writer.c
+++ b/src/plugins/influxdb-writer.c
@@ -50,16 +50,19 @@ void influxdb_write_curl_cb(void *closure, int status, CURL *curl, const char *r
 	}
 }
 
-
-static void serialize_list_to_query(char *query, struct list *node) {
+// query: destination buffer
+// node: head node of the list
+// list_sep: separator to append in front of the list
+// item_sep: separator to append between items of the list
+static void serialize_list_to_query(char *query, struct list *node, const char *list_sep, const char *item_sep) {
 	bool first = true;
 
 	while(node != NULL) {
 		if(first) {
-			concatenate(query, node->key, " ");
+			concatenate(query, node->key, list_sep);
 			first = false;
 		} else {
-			concatenate(query, node->key, ",");
+			concatenate(query, node->key, item_sep);
 		}
 
 		if(json_object_is_type(node->value, json_type_string))
@@ -77,13 +80,15 @@ static size_t format_write_args(char *query, struct series_t *serie)
 
 	strncat(query, serie->name, strlen(serie->name));
 
-	serialize_list_to_query(query, serie->serie_columns.tags);
-	serialize_list_to_query(query, serie->serie_columns.fields);
-
-	asprintf(&ts, "%lu", serie->timestamp);
-	concatenate(query, ts, " ");
+	serialize_list_to_query(query, serie->serie_columns.tags, ",", ",");
+	serialize_list_to_query(query, serie->serie_columns.fields, " ", ",");
 
-	return strlen(query);
+	if (asprintf(&ts, "%lu", serie->timestamp) > 0) {
+		concatenate(query, ts, " ");
+		free(ts);
+		return strlen(query);
+	}
+	return -1;
 }
 
 CURL *make_curl_write_post(afb_api_t apiHandle, const char *url, json_object *metricsJ)
@@ -121,7 +126,7 @@ CURL *make_curl_write_post(afb_api_t apiHandle, const char *url, json_object *me
 			}
 			else {
 				len_write = format_write_args(write, serie);
-				if(len_write) {
+				if(len_write > 0) {
 					post_data[i] = malloc(len_write + 1);
 					strcpy(post_data[i], write);
 					memset(write, 0, len_write);