Added "Points" API

diff --git a/include/libmormegil/Points.hh b/include/libmormegil/Points.hh
new file mode 100644 (file)
index 0000000..89f828a
--- /dev/null
+++ b/include/libmormegil/Points.hh
@@ -0,0 +1,77 @@
+// libmormegil/Points.hh
+//
+// Copyright 2010 Martin Read. All rights reserved.
+// 
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions
+// are met:
+// 1. Redistributions of source code must retain the above copyright
+//    notice, this list of conditions and the following disclaimer.
+// 2. Redistributions in binary form must reproduce the above copyright
+//    notice, this list of conditions and the following disclaimer in the
+//    documentation and/or other materials provided with the distribution.
+// 3. Neither the name of the author nor the names of any other contributors
+//    may be used to endorse or promote products derived from this software
+//    without their specific prior written permission.
+// 
+// THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+// ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+// OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+// HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+// LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+// OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+// SUCH DAMAGE.
+
+#ifndef libmormegil_Points_hh
+#define libmormegil_Points_hh
+#include <algorithm>
+#include <stdint.h>
+
+#ifndef libmormegil_divup_hh
+#include <libmormegil/divup.hh>
+#endif
+
+#ifndef libmormegil_abs_hh
+#include <libmormegil/abs.hh>
+#endif
+
+namespace libmormegil
+{
+    class Points
+    {
+    private:
+        int32_t maxval;
+        int32_t curr;
+    public:
+        enum Gain_mode {
+            Gain_match,
+            Gain_proportional,
+            Gain_norestore
+        };
+        int32_t boost(int32_t amount)
+        {
+            amount = std::min(0x7fffffff - curr, amount);
+            curr += amount;
+            return amount;
+        }
+        int32_t restore(int32_t amount)
+        {
+            amount = std::max(0, std::min(amount, maxval - curr));
+            curr += amount;
+            return amount;
+        }
+        // gain() is non-inline because it's messy.
+        int32_t gain(int32_t amount, Gain_mode mode);
+        int32_t lose(int32_t amount) { amount = std::max(0, maxval); return amount; }
+        int32_t current() const { return curr; }
+        int32_t maximum() const { return maxval; }
+    };
+}
+#endif // libmormegil_Points_hh
+
+// vim:ts=8:sw=4:expandtab:fo=c
+// libmormegil/Points.hh

diff --git a/src/points.cc b/src/points.cc
new file mode 100644 (file)
index 0000000..09a7e1f
--- /dev/null
+++ b/src/points.cc
@@ -0,0 +1,62 @@
+// points.cc
+//
+// Copyright 2010 Martin Read. All rights reserved.
+// 
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions
+// are met:
+// 1. Redistributions of source code must retain the above copyright
+//    notice, this list of conditions and the following disclaimer.
+// 2. Redistributions in binary form must reproduce the above copyright
+//    notice, this list of conditions and the following disclaimer in the
+//    documentation and/or other materials provided with the distribution.
+// 3. Neither the name of the author nor the names of any other contributors
+//    may be used to endorse or promote products derived from this software
+//    without their specific prior written permission.
+// 
+// THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+// ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+// OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+// HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+// LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+// OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+// SUCH DAMAGE.
+
+#include <string.h>
+#include <errno.h>
+#include <libmormegil/Points.hh>
+
+int32_t libmormegil::Points::gain(int32_t amount, libmormegil::Points::Gain_mode mode)
+{
+    amount = std::min(amount, 0x7fffffff - maxval);
+    if (amount < 1)
+    {
+        return 0;
+    }
+    switch (mode)
+    {
+    case Gain_proportional:
+        curr *= (maxval + amount);
+        /* for non-zero gain_proportional, always gain at least one point. */
+        curr = divup(curr, maxval);
+        maxval += amount;
+        return amount;
+    case Gain_match:
+        maxval += amount;
+        curr += amount;
+        return amount;
+    case Gain_norestore:
+        maxval += amount;
+        return amount;
+    }
+    // should never happen, but be paranoid.
+    errno = ENOTSUP;
+    return -1;
+}
+
+// vim:ts=8:sw=4:expandtab:fo=cq
+// points.cc