Allow empty imginfo string format

Commit 37d3050 "Added imginfo format check" breaks -f "" which used
to be very usefull to print data as text format on stdout. Allowing
an empty -f was particularly interesting because there was no
<width>x<height> printed out.

Before :

[root@nagios-2b ~]# rrdtool graph /dev/null -f "" --start -1d \
    DEF:d=/var/lib/rrd/nagios-2b/load.rrd:load5:AVERAGE \
    VDEF:v=d,AVERAGE \
    PRINT:v:%.6lf
5.284605

After :

[root@nagios-2b ~]# rrdtool graph /dev/null -f "" --start -1d \
    DEF:d=/var/lib/rrd/nagios-2b/load.rrd:load5:AVERAGE \
    VDEF:v=d,AVERAGE \
    PRINT:v:%.6lf
ERROR: bad format for imginfo

diff --git a/src/rrd_graph.c b/src/rrd_graph.c
index e714e4f483a651883f23a1311077697b1bbf8330..4d91793a0271a08a212cf6d3730b531b8d8004ee 100644 (file)
--- a/src/rrd_graph.c
+++ b/src/rrd_graph.c
@@ -4139,7 +4139,7 @@ rrd_info_t *rrd_graph_v(
      ** Also, if needed, print a line with information about the image.
      */
 
-    if (im.imginfo) {
+    if (im.imginfo && *im.imginfo) {
         rrd_infoval_t info;
         char     *path;
         char     *filename;