From cb034b9b374927c7552e36dcbc306d8456b2a0cb Mon Sep 17 00:00:00 2001
From: Damjan Marion <damarion@cisco.com>
Date: Wed, 28 Dec 2016 18:38:59 +0100
Subject: Move java,lua api and remaining plugins to src/

Change-Id: I1c3b87e886603678368428ae56a6bd3327cbc90d
Signed-off-by: Damjan Marion <damarion@cisco.com>
---
 src/plugins/ioam/lib-pot/math64.h | 159 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 159 insertions(+)
 create mode 100644 src/plugins/ioam/lib-pot/math64.h

(limited to 'src/plugins/ioam/lib-pot/math64.h')

diff --git a/src/plugins/ioam/lib-pot/math64.h b/src/plugins/ioam/lib-pot/math64.h
new file mode 100644
index 00000000000..4c608a37de4
--- /dev/null
+++ b/src/plugins/ioam/lib-pot/math64.h
@@ -0,0 +1,159 @@
+/* 
+ * math64.h provides the 64 bit unsigned integer add, multiply followed by  modulo operation
+ * The linux/math64.h provides divide and multiply 64 bit integers but:
+ * 1. multiply: mul_u64_u64_shr - only returns 64 bits of the result and has to be called
+ *                     twice to get the complete 128 bits of the result.
+ * 2. Modulo operation of the result of  addition and multiplication of u64 that may result 
+ *                        in integers > 64 bits is not supported
+ * Hence this header to combine add/multiply followed by modulo of u64 integrers
+ * always resulting in u64.
+ * 
+ * Copyright (c) 2016 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#ifndef include_vnet_math64_h
+#define include_vnet_math64_h
+#include <stdint.h>
+
+/* 
+ * multiplies and returns result in hi and lo 
+ */
+static inline void mul64by64(u64 a, u64 b, u64 * hi, u64 * lo)
+{
+    u64 a_lo = (u64) (uint32_t) a;
+    u64 a_hi = a >> 32;
+    u64 b_lo = (u64) (u32) b;
+    u64 b_hi = b >> 32;
+
+    u64 p0 = a_lo * b_lo;
+    u64 p1 = a_lo * b_hi;
+    u64 p2 = a_hi * b_lo;
+    u64 p3 = a_hi * b_hi;
+
+    u32 cy = (u32) (((p0 >> 32) + (u32) p1 + (u32) p2) >> 32);
+
+    *lo = p0 + (p1 << 32) + (p2 << 32);
+    *hi = p3 + (p1 >> 32) + (p2 >> 32) + cy;
+    return;
+}
+
+#define TWO64 18446744073709551616.0
+
+static inline u64 mod128by64(u64 x, u64 y, u64 m, double di)
+{
+    u64 q1, q2, q;
+    u64 p1, p0;
+    double dq;
+
+    /* calculate quotient first pass 53 bits */
+    dq = (TWO64 * (double)x + (double)y) * di;
+
+    if (dq >= TWO64)
+        q1 = 0xfffffffffffff800L;
+    else
+        q1 = dq;
+
+    /* q1 * m to compare the product to the dividend.  */
+    mul64by64(q1, m, &p1, &p0);
+
+    /* Adjust quotient. is it > actual result: */
+    if (x < p1 || (x == p1 && y < p0))
+    {
+        /* q1 > quotient.  calculate abs remainder */
+        x = p1 - (x + (p0 < y));
+        y = p0 - y;
+
+        /* use the remainder as new dividend to adjust quotient */
+        q2 = (u64) ((TWO64 * (double)x + (double)y) * di);
+        mul64by64(q2, m, &p1, &p0);
+
+        q = q1 - q2;
+        if (x < p1 || (x == p1 && y <= p0))
+        {
+            y = p0 - y;
+        }
+        else
+        {
+            y = p0 - y;
+            y += m;
+            q--;
+        }
+    }
+    else
+    {
+        x = x - (p1 + (y < p0));
+        y = y - p0;
+
+        q2 = (u64) ((TWO64 * (double)x + (double)y) * di);
+        mul64by64(q2, m, &p1, &p0);
+
+        q = q1 + q2;
+        if (x < p1 || (x == p1 && y < p0))
+        {
+            y = y - p0;
+            y += m;
+            q--;
+        }
+        else
+        {
+            y = y - p0;
+            if (y >= m)
+            {
+                y -= m;
+                q++;
+            }
+        }
+    }
+
+    return y;
+}
+
+/* 
+ * returns a % p
+ */
+static inline u64 mod64by64(u64 a, u64 p, u64 primeinv)
+{
+    return (mod128by64(0, a, p, primeinv));
+}
+
+static inline void add64(u64 a, u64 b, u64 * whi, u64 * wlo)
+{
+    *wlo = a + b;
+    if (*wlo < a)
+        *whi = 1;
+
+}
+
+/* 
+ * returns (a + b)%p
+ */
+static inline u64 add64_mod(u64 a, u64 b, u64 p, double pi)
+{
+    u64 shi = 0, slo = 0;
+
+    add64(a, b, &shi, &slo);
+    return (mod128by64(shi, slo, p, pi));
+}
+
+/* 
+ * returns (ab) % p
+ */
+static inline u64 mul64_mod(u64 a, u64 b, u64 p, double pi)
+{
+    u64 phi = 0, plo = 0;
+
+    mul64by64(a, b, &phi, &plo);
+    return (mod128by64(phi, plo, p, pi));
+}
+
+#endif
-- 
cgit 1.2.3-korg