1 files changed, 71 insertions, 0 deletions
diff --git a/src/ints/cmp.hpp b/src/ints/cmp.hpp
new file mode 100644
index 0000000..08308e1
--- /dev/null
+++ b/src/ints/cmp.hpp
@@ -0,0 +1,71 @@
+#pragma once
+//    cmp.hpp - comparison related operations
+//
+//    Copyright © 2014 Ben Longbons <b.r.longbons@gmail.com>
+//
+//    This file is part of The Mana World (Athena server)
+//
+//    This program is free software: you can redistribute it and/or modify
+//    it under the terms of the GNU General Public License as published by
+//    the Free Software Foundation, either version 3 of the License, or
+//    (at your option) any later version.
+//
+//    This program is distributed in the hope that it will be useful,
+//    but WITHOUT ANY WARRANTY; without even the implied warranty of
+//    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+//    GNU General Public License for more details.
+//
+//    You should have received a copy of the GNU General Public License
+//    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+#include "fwd.hpp"
+
+#include <limits>
+
+#include "../diagnostics.hpp"
+
+
+namespace tmwa
+{
+namespace ints
+{
+    DIAG_PUSH();
+    DIAG_I(type_limits);
+    template<class T, class U>
+    T saturate(const U& v)
+    {
+        typedef std::numeric_limits<T> Tlim;
+        typedef std::numeric_limits<U> Ulim;
+
+        if (Tlim::is_signed == Ulim::is_signed)
+        {
+            if (v > Tlim::max())
+                return Tlim::max();
+            if (v < Tlim::min())
+                return Tlim::min();
+            return v;
+        }
+        else if (Ulim::is_signed)
+        {
+            // from signed to unsigned
+
+            // Not like v < Tlim::min(), even though Tlim::min() == 0
+            if (v < 0)
+                return 0;
+            if (v > Tlim::max())
+                return Tlim::max();
+            return v;
+        }
+        else // Tlim::is_signed
+        {
+            // from unsigned to signed
+            if (v > Tlim::max())
+                return Tlim::max();
+            return v;
+        }
+    }
+    DIAG_POP();
+} // namespace ints
+
+using ints::saturate;
+} // namespace tmwa