move the C sources to the subfolder pgf again for backwards compatibility

src/runtime/c/pgf/vector.h

@@ -0,0 +1,32 @@
+#ifndef VECTOR_H
+#define VECTOR_H
+
+template <class A>
+struct PgfVector {
+    size_t len;
+    A data[];
+};
+
+template <class A> inline
+ref<PgfVector<A>> vector_new(size_t len)
+{
+    ref<PgfVector<A>> res = DB::malloc<PgfVector<A>>(sizeof(PgfVector<A>)+len*sizeof(A));
+    res->len = len;
+    return res;
+}
+
+template <class C, class A> inline
+ref<C> vector_new(PgfVector<A> C::* field, size_t len)
+{
+    ref<C> res = DB::malloc<C>(((size_t) &(((C*) NULL)->*field))+sizeof(PgfVector<A>)+len*sizeof(A));
+    (res->*field).len = len;
+    return res;
+}
+
+template <class A> inline
+ref<A> vector_elem(ref<PgfVector<A>> v, size_t index)
+{
+    return ref<A>::from_ptr(&v->data[index]);
+}
+
+#endif // VECTOR_H