Bugfix: fallback implementation for integer div and remainder

this fallback allows to use our custom floordiv
for all integral types. This solves compilation problems
on 32bit, when gavl_time_t is defined to long long int

src/lib/util.hpp

@@ -59,7 +59,16 @@ namespace util {
   
   /** helper to treat int or long division uniformly */
   template<typename I>
-  struct IDiv;
+  struct IDiv
+    {
+      I quot;
+      I rem;
+      
+      IDiv (I num, I den)
+        : quot(num/den)
+        , rem(num - quot*den)
+        { }
+    };
   
   template<>
   struct IDiv<int>

tests/lib/util-floordiv-test.cpp

@@ -90,6 +90,7 @@ namespace test {
   
   /**********************************************************************
    * @test Evaluate a custom built integer floor function.
+   *       Also known as Knuth's floor division.
    *       This function is crucial for Lumiera's rule of quantisation
    *       of time values into frame intervals. This rule requires time
    *       points to be rounded towards the next lower frame border always,
@@ -111,6 +112,12 @@ namespace test {
         {
           verifyBehaviour ();
           
+          verifyIntegerTypes<int>();
+          verifyIntegerTypes<long>();
+          verifyIntegerTypes<short>();
+          verifyIntegerTypes<int64_t>();
+          verifyIntegerTypes<long long int>();
+          
           if (!isnil (arg))
             runPerformanceTest();
         }
@@ -147,6 +154,22 @@ namespace test {
         }
       
       
+      template<typename I>
+      void
+      verifyIntegerTypes ()
+        {
+          I n,d,expectedRes;
+          
+          for (int i=-12; i <= 12; ++i)
+            {
+              n = i;
+              d = 4;
+              expectedRes = floordiv (i,4);
+              CHECK (floordiv(n,d) == expectedRes);
+            }
+        }
+      
+      
       
       /** @test timing measurements to compare implementation details.
        *  This test uses a sequence of random integers, where the values