From bac3da61644515f05663789b122554dc77549286 Mon Sep 17 00:00:00 2001
From: Luca Muscariello <lumuscar+fdio@cisco.com>
Date: Thu, 17 Jan 2019 13:47:57 +0100
Subject: This is the first commit of the hicn project

Change-Id: I6f2544ad9b9f8891c88cc4bcce3cf19bd3cc863f
Signed-off-by: Luca Muscariello <lumuscar+fdio@cisco.com>
---
 libtransport/src/hicn/transport/utils/endianess.h | 136 ++++++++++++++++++++++
 1 file changed, 136 insertions(+)
 create mode 100755 libtransport/src/hicn/transport/utils/endianess.h

(limited to 'libtransport/src/hicn/transport/utils/endianess.h')

diff --git a/libtransport/src/hicn/transport/utils/endianess.h b/libtransport/src/hicn/transport/utils/endianess.h
new file mode 100755
index 000000000..a3ec21c90
--- /dev/null
+++ b/libtransport/src/hicn/transport/utils/endianess.h
@@ -0,0 +1,136 @@
+/*
+ * Copyright (c) 2017-2019 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.
+ */
+
+#pragma once
+
+#include <hicn/transport/portability/portability.h>
+
+#include <arpa/inet.h>
+#include <cstring>
+
+namespace utils {
+
+namespace {
+
+template <size_t Size>
+struct uint_types_by_size;
+
+#define GENERATOR(sz, fn)                                                    \
+  static TRANSPORT_ALWAYS_INLINE uint##sz##_t byteswap_gen(uint##sz##_t v) { \
+    return fn(v);                                                            \
+  }                                                                          \
+  template <>                                                                \
+  struct uint_types_by_size<sz / 8> {                                        \
+    using type = uint##sz##_t;                                               \
+  };
+
+GENERATOR(8, uint8_t)
+#ifdef _MSC_VER
+GENERATOR(64, _byteswap_uint64)
+GENERATOR(32, _byteswap_ulong)
+GENERATOR(16, _byteswap_ushort)
+#else
+GENERATOR(64, __builtin_bswap64)
+GENERATOR(32, __builtin_bswap32)
+GENERATOR(16, __builtin_bswap16)
+#endif
+
+template <typename T>
+struct EndianInt {
+  static_assert(
+      (std::is_integral<T>::value && !std::is_same<T, bool>::value) ||
+          std::is_floating_point<T>::value,
+      "template type parameter must be non-bool integral or floating point");
+
+  static T swap(T x) {
+    // we implement this with memcpy because that is defined behavior in C++
+    // we rely on compilers to optimize away the memcpy calls
+    constexpr auto s = sizeof(T);
+    using B = typename uint_types_by_size<s>::type;
+    B b;
+    std::memcpy(&b, &x, s);
+    b = byteswap_gen(b);
+    std::memcpy(&x, &b, s);
+    return x;
+  }
+  static T big(T x) {
+    return portability::little_endian_arch ? EndianInt::swap(x) : x;
+  }
+  static T little(T x) {
+    return portability::big_endian_arch ? EndianInt::swap(x) : x;
+  }
+};
+
+}  // namespace
+
+// big* convert between native and big-endian representations
+// little* convert between native and little-endian representations
+// swap* convert between big-endian and little-endian representations
+//
+// ntohs, htons == big16
+// ntohl, htonl == big32
+#define GENERATOR1(fn, t, sz) \
+  static t fn##sz(t x) { return fn<t>(x); }
+
+#define GENERATOR2(t, sz) \
+  GENERATOR1(swap, t, sz) \
+  GENERATOR1(big, t, sz)  \
+  GENERATOR1(little, t, sz)
+
+#define GENERATOR3(sz)         \
+  GENERATOR2(uint##sz##_t, sz) \
+  GENERATOR2(int##sz##_t, sz)
+
+class Endian {
+ public:
+  enum class Order : uint8_t { LITTLE, BIG };
+
+  static constexpr Order order =
+      portability::little_endian_arch ? Order::LITTLE : Order::BIG;
+
+  template <typename T>
+  static T swap(T x) {
+    return EndianInt<T>::swap(x);
+  }
+
+  template <typename T>
+  static T big(T x) {
+    return EndianInt<T>::big(x);
+  }
+
+  template <typename T>
+  static T little(T x) {
+    return EndianInt<T>::little(x);
+  }
+
+#if !defined(__ANDROID__)
+  GENERATOR3(64)
+  GENERATOR3(32)
+  GENERATOR3(16)
+  GENERATOR3(8)
+#endif
+};
+
+template <typename T>
+static TRANSPORT_ALWAYS_INLINE T ntoh(T x) {
+  return Endian::order == Endian::Order::LITTLE ? Endian::little(x) : x;
+}
+
+template <typename T>
+static TRANSPORT_ALWAYS_INLINE T hton(T x) {
+  return Endian::order == Endian::Order::LITTLE ? Endian::big(x) : x;
+}
+
+}  // namespace utils
\ No newline at end of file
-- 
cgit 1.2.3-korg