Compression filter: Reorganised verification order of transform.

1 files changed, 6 insertions, 4 deletions

diff --git a/src/lib/filters/comp_filter.cpp b/src/lib/filters/comp_filter.cpp
index 5e9ef577f..f909db4a7 100644
--- a/src/lib/filters/comp_filter.cpp
+++ b/src/lib/filters/comp_filter.cpp
@@ -1,6 +1,7 @@
 /*
 * Filter interface for compression
 * (C) 2014,2015 Jack Lloyd
+* (C) 2015 Matej Kenda
 *
 * Botan is released under the Simplified BSD License (see license.txt)
 */
@@ -23,13 +24,14 @@ Decompression_Filter::Decompression_Filter(const std::string& type, size_t bs) :
 Compression_Decompression_Filter::Compression_Decompression_Filter(Transform* transform, size_t bs) :
    m_buffersize(std::max<size_t>(256, bs)), m_buffer(m_buffersize)
    {
+   if (!transform)
+      {
+         throw std::invalid_argument("Transform is null");
+      }
    m_transform.reset(dynamic_cast<Compressor_Transform*>(transform));
    if(!m_transform)
       {
-      if (transform)
-         throw std::invalid_argument("Transform " + transform->name() + " is not a compressor");
-      else
-         throw std::invalid_argument("Transform is null");
+      throw std::invalid_argument("Transform " + transform->name() + " is not a compressor");
       }
    }