Use a more secure command line building method

Previously, a command is built by string concatenation. Here, the
distinction between a value and multiple params got lost. Solve this
by using an array for shell arguments. As the escaping is now removed
from the `rrd_gen_graph` function, the canvas style needs to manually
add those quotes to make the JS code still work. That only supports
double-quotes, so hopefully nobody creates a name with a double quote
as that would break the fragile JS command line parser.

Separate the rrdtool options from the rrdtool graph command to make the
`$graph_type == 'canvas'` option work (it would otherwise not understand
the `rrdtool graph - -a PNG` option).

Merge the SVG and PNG cases as they are the same except for the
Content-Type header.

Fix a missing html escape in a debug style.

1 files changed, 6 insertions, 6 deletions

diff --git a/type/Uptime.class.php b/type/Uptime.class.php
index e57df0b..52af3a4 100644
--- a/type/Uptime.class.php
+++ b/type/Uptime.class.php
@@ -45,16 +45,16 @@ class Type_Uptime extends Type_Base {
                         $color = is_array($this->colors) ? (isset($this->colors[$source])?$this->colors[$source]:$this->colors[$c++]) : $this->colors;
 
                         //current value
-                        $rrdgraph[] = sprintf('"LINE1:area_%s#%s:%s"', crc32hex($source), $this->validate_color($color), $this->rrd_escape($legend));
-                        $rrdgraph[] = sprintf('"GPRINT:c_avg_%s:LAST:%s days\\l"', crc32hex($source), $this->rrd_format);
+                        $rrdgraph[] = sprintf('LINE1:area_%s#%s:%s', crc32hex($source), $this->validate_color($color), $this->rrd_escape($legend));
+                        $rrdgraph[] = sprintf('GPRINT:c_avg_%s:LAST:%s days\\l', crc32hex($source), $this->rrd_format);
 
                         //max value
-                        $rrdgraph[] = sprintf('"LINE1:v_max_%s#FF0000:Maximum:dashes"', crc32hex($source));
-                        $rrdgraph[] = sprintf('"GPRINT:v_max_%s:%s days\\l"', crc32hex($source), $this->rrd_format);
+                        $rrdgraph[] = sprintf('LINE1:v_max_%s#FF0000:Maximum:dashes', crc32hex($source));
+                        $rrdgraph[] = sprintf('GPRINT:v_max_%s:%s days\\l', crc32hex($source), $this->rrd_format);
 
                         //avg value
-                        $rrdgraph[] = sprintf('"LINE1:v_avg_%s#0000FF:Average:dashes"', crc32hex($source));
-                        $rrdgraph[] = sprintf('"GPRINT:v_avg_%s:%s days\\l"', crc32hex($source), $this->rrd_format);
+                        $rrdgraph[] = sprintf('LINE1:v_avg_%s#0000FF:Average:dashes', crc32hex($source));
+                        $rrdgraph[] = sprintf('GPRINT:v_avg_%s:%s days\\l', crc32hex($source), $this->rrd_format);
                 }
 
                 return $rrdgraph;