From: Julien Thomas <jthomas@exosec.fr>
Date: Thu, 6 Nov 2014 00:36:14 +0000 (+0100)
Subject: Allow empty imginfo format string
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=27a15e5d9f0b49b2670fb8e2aaa978ed858b5e8e;p=thirdparty%2Frrdtool-1.x.git

Allow empty imginfo format string

Empty -f|--imginfo used to be very usefull to print data as text format
on stdout. It was allowed up to 1.4.7 and was particularly interesting
because there was no filename/width/height printed out. The "feature"
was broken in 1.4.8 by the addition of a format check on the imginfo
value. The recent rework based on regexp still breaks it. Adding it back
would preserve compatibility on scripts/parser eating rrdtool graph
/dev/null -f '' output.

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 915510b4..de629963 100644
--- a/src/rrd_graph.c
+++ b/src/rrd_graph.c
@@ -4021,7 +4021,7 @@ 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;