decklink: Don't crash when getting hw serial number doesn't return OK

If the return value isn't OK, it means we might be getting data that
points to an invalid memory address. That shouldn't make us crash.

diff --git a/sys/decklink/gstdecklink.cpp b/sys/decklink/gstdecklink.cpp
index 58af0c6074accd7838441d38e9c7f2d86355cde6..85498c9b13262bd34c2e9ebe16835809b67fb83d 100644 (file)
--- a/sys/decklink/gstdecklink.cpp
+++ b/sys/decklink/gstdecklink.cpp
@@ -1239,11 +1239,13 @@ init_devices (gpointer data)
           devices[i].input.
           config->GetString (bmdDeckLinkConfigDeviceInformationSerialNumber,
           (COMSTR_T *) & serial_number);
-      CONVERT_COM_STRING (serial_number);
-      devices[i].output.hw_serial_number = g_strdup (serial_number);
-      devices[i].input.hw_serial_number = g_strdup (serial_number);
-      GST_DEBUG ("device %d has serial number %s", i, serial_number);
-      FREE_COM_STRING (serial_number);
+      if (ret == S_OK) {
+        CONVERT_COM_STRING (serial_number);
+        devices[i].output.hw_serial_number = g_strdup (serial_number);
+        devices[i].input.hw_serial_number = g_strdup (serial_number);
+        GST_DEBUG ("device %d has serial number %s", i, serial_number);
+        FREE_COM_STRING (serial_number);
+      }
     }
 
     ret = decklink->QueryInterface (IID_IDeckLinkAttributes,