Fixed cDevice::StillPicture(), making sure it doesn't call the derived class's function if no buffer has been allocated

HISTORY

@@ -7052,7 +7052,7 @@ Video Disk Recorder Revision History
 - Fixed handling IDLEPRIORITY in cDvbDevice::ProvidesChannel() (thanks to Frank
   Schmirler).
 
-2012-04-24: Version 1.7.28
+2012-04-26: Version 1.7.28
 
 - Fixed cPixmapMemory::DrawEllipse() for quadrants -1 and -4.
 - Fixed getting the maximum short channel name length in case there are no short names
@@ -7085,3 +7085,5 @@ Video Disk Recorder Revision History
   to have them react immediately in case any change to a plugin's setup parameter
   has an effect on the OSD.
 - The Timers list is now marked as modified whenever a recording starts or ends.
+- Fixed cDevice::StillPicture(), making sure it doesn't call the derived class's
+  function if no buffer has been allocated.

device.c

@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: device.c 2.59 2012/04/04 09:48:00 kls Exp $
+ * $Id: device.c 2.60 2012/04/26 09:40:36 kls Exp $
  */
 
 #include "device.h"
@@ -1181,8 +1181,10 @@ void cDevice::StillPicture(const uchar *Data, int Length)
               return;
               }
            }
-     StillPicture(buf, Size);
-     free(buf);
+     if (buf) {
+        StillPicture(buf, Size);
+        free(buf);
+        }
      }
 }