rrd plugin: Fix writing of long values.

The buffer provided for value_list_to_string() was not long enough to
fit a timestamp and a negative value using exponent and maximum
precision of the gauge format.

Signed-off-by: Florian Forster <octo@collectd.org>

diff --git a/src/rrdtool.c b/src/rrdtool.c
index 5f42561..558b800 100644 (file)
--- a/src/rrdtool.c
+++ b/src/rrdtool.c
@@ -803,7 +803,7 @@ static int rrd_write(const data_set_t *ds, const value_list_t *vl,
   if (value_list_to_filename(filename, sizeof(filename), vl) != 0)
     return -1;
 
-  char values[32 * ds->ds_num];
+  char values[32 * (ds->ds_num + 1)];
   if (value_list_to_string(values, sizeof(values), ds, vl) != 0)
     return -1;