Changeset 082b7f1 in mainline for kernel/generic/include/macros.h

Timestamp:

2012-11-02T19:07:28Z (12 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

0941e9ae

Parents:

35a3d950

Message:

Make the overlaps() macro accept zero sizes and also tolerate
bases and sizes that wrap-around -1UL back to 0 when added together.

File:

• kernel/generic/include/macros.h (modified) (1 diff)

kernel/generic/include/macros.h

@@ -52 +52 @@
     uint64_t sz2)
 {
-        uint64_t e1 = s1 + sz1;
-        uint64_t e2 = s2 + sz2;
-        
-        return ((s1 < e2) && (s2 < e1));
+        uint64_t e1 = s1 + sz1 - 1;
+        uint64_t e2 = s2 + sz2 - 1;
+
+        /* both sizes are non-zero */
+        if (sz1 && sz2)
+                return ((s1 <= e2) && (s2 <= e1));
+
+        /* one size is non-zero */
+        if (sz2)
+                return ((s1 >= s2) && (s1 <= e2));
+        if (sz1)
+                return ((s2 >= s1) && (s2 <= e1));
+
+        /* both are zero */
+        return (s1 == s2);
 }