error handling

libraries/chart.lib.php

@@ -36,7 +36,9 @@ function PMA_chart_status($data)
     $chart = new PMA_pChart_Pie(
             __('Query statistics'),
             array_slice($chartData, 0, 20, true));
-    echo $chart->toString();
+    $chartCode = $chart->toString();
+    PMA_handle_chart_err($chart->getErrors());
+    echo $chartCode;
 }
 
 /*
@@ -54,7 +56,9 @@ function PMA_chart_profiling($data)
     $chart = new PMA_pChart_Pie(
             __('Query execution time comparison (in microseconds)'),
             $chartData);
-    echo $chart->toString();
+    $chartCode = $chart->toString();
+    PMA_handle_chart_err($chart->getErrors());
+    echo $chartCode;
 }
 
 /*
@@ -205,7 +209,13 @@ function PMA_chart_results($data, &$chartSettings)
 
     $chartCode = $chart->toString();
     $chartSettings = $chart->getSettings();
+    PMA_handle_chart_err($chart->getErrors());
     return $chartCode;
 }
 
+function PMA_handle_chart_err($errors)
+{
+    PMA_warnMissingExtension('GD', false, 'GD extension is needed for charts.');
+}
+
 ?>

libraries/chart/pma_chart.php

@@ -71,6 +71,11 @@ class PMA_Chart
      */
     private $userSpecifiedSettings = null;
 
+    /*
+     * Error codes will be stored here
+     */
+    protected $errors = null;
+
     function __construct($options = null)
     {
         $this->userSpecifiedSettings = $options;
@@ -133,6 +138,11 @@ class PMA_Chart
     {
         return $this->settings;
     }
+
+    public function getErrors()
+    {
+        return $this->errors;
+    }
 }
 
 ?>

libraries/chart/pma_pchart_chart.php

@@ -136,7 +136,8 @@ abstract class PMA_pChart_Chart extends PMA_Chart
             return '<img id="chart" src="data:image/png;base64,'.$this->imageEncoded.'" />';
         }
         else {
-            return __('GD library needed for chart is missing.');
+            $this->errors = 1; // stub
+            return '';
         }
     }