New function CollTransfer. Change CollAt and CollAtUnchecked to take a const

Collection pointer instead of just a Collection pointer. This makes more
sense, since the functions do not change the collection.


git-svn-id: svn://svn.cc65.org/cc65/trunk@5224 b7a2c559-68d2-44c3-8de9-860c34a00d81

src/common/coll.c

@@ -167,7 +167,7 @@ void CollAppend (Collection* C, void* Item)
 
 
 #if !defined(HAVE_INLINE)
-void* CollAt (Collection* C, unsigned Index)
+void* CollAt (const Collection* C, unsigned Index)
 /* Return the item at the given index */
 {
     /* Check the index */
@@ -438,6 +438,26 @@ static void QuickSort (Collection* C, int Lo, int Hi,
 
 
 
+void CollTransfer (Collection* Dest, const Collection* Source)
+/* Transfer all items from Source to Dest. Anything already in Dest is left
+ * untouched. The items in Source are not changed and are therefore in both
+ * Collections on return.
+ */                                                           
+{
+    /* Be sure there's enough room in Dest */
+    CollGrow (Dest, Dest->Count + Source->Count);
+
+    /* Copy the items */
+    memcpy (Dest->Items + Dest->Count, 
+            Source->Items, 
+            Source->Count * sizeof (Source->Items[0]));
+
+    /* Bump the counter */
+    Dest->Count += Source->Count;
+}
+
+
+
 void CollSort (Collection* C,
 	       int (*Compare) (void*, const void*, const void*),
 	       void* Data)