When we take the difference between two pointers, the result is technically

signed.  pdiff() makes sure we never get a negative value.


git-svn-id: http://www.varnish-cache.org/svn/trunk/varnish-cache@2016 d4fa192b-c00b-0410-8231-f00ffab90ce4

bin/varnishd/cache.h

@@ -587,3 +587,17 @@ do {							\
 		    __func__, __FILE__, __LINE__);	\
 } while (0);
 #endif
+
+/*
+ * A normal pointer difference is signed, but we never want a negative value
+ * so this little tool will make sure we don't get that.
+ */
+
+static inline unsigned
+pdiff(const void *b, const void *e)
+{
+
+	assert(b <= e);
+	return
+	    ((unsigned)((const unsigned char *)e - (const unsigned char *)b));
+}