BugID: 738

Make default alignment max 8

LCS/Blob/include/Blob/BlobField.h

@@ -158,7 +158,8 @@ namespace LOFAR {
 
       // Return the greatest power of 2 that divides the value.
       // It is used to make the default alignment a power of 2.
-      static uint p2divider (uint value);
+      // It the result exceeds the maximum, it is set to the maximum.
+      static uint p2divider (uint value, uint maxval=8);
 
       // Helper functions for BlobFieldSet.
       // <group>
@@ -237,6 +238,7 @@ namespace LOFAR {
   // that is a power of 2. E.g. for an array of structs containing 3 floats,
   // the element size is 12, but the basic element size is 4.
   // For a struct containing 2 floats the basic element size would be 8.
+  // The default alignment is maximum 8.
   //
   // Because a blob can be used to exchange data between different systems,
   // it must be possible to convert data as needed (for instance from big to

LCS/Blob/src/BlobField2.cc

@@ -161,7 +161,7 @@ namespace LOFAR {
     }
   }
 
-  uint BlobFieldBase::p2divider (uint value)
+  uint BlobFieldBase::p2divider (uint value, uint maxval)
   {
     if ((value & (value-1)) != 0) {
       // No power of 2, so find greatest power of 2 that divides value.
@@ -172,7 +172,7 @@ namespace LOFAR {
 	v /= 2;
       }
     }
-    return value;
+    return std::min (value, maxval);
   }
 
 } // end namespace