Extract simple integer math into its own module

1 files changed, 20 insertions, 0 deletions

diff --git a/src/lib/intmath/cmp.h b/src/lib/intmath/cmp.h
new file mode 100644
index 0000000000..90ea3ca079
--- /dev/null
+++ b/src/lib/intmath/cmp.h
@@ -0,0 +1,20 @@
+/* Copyright (c) 2003-2004, Roger Dingledine
+ * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
+ * Copyright (c) 2007-2018, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+#ifndef TOR_INTMATH_CMP_H
+#define TOR_INTMATH_CMP_H
+
+/* Return <b>v</b> if it's between <b>min</b> and <b>max</b>.  Otherwise
+ * return <b>min</b> if <b>v</b> is smaller than <b>min</b>, or <b>max</b> if
+ * <b>b</b> is larger than <b>max</b>.
+ *
+ * Requires that <b>min</b> is no more than <b>max</b>. May evaluate any of
+ * its arguments more than once! */
+#define CLAMP(min,v,max)                        \
+  ( ((v) < (min)) ? (min) :                     \
+    ((v) > (max)) ? (max) :                     \
+    (v) )
+
+#endif /* !defined(TOR_INTMATH_CMP_H) */