version 3.0

common/endian.h

@@ -0,0 +1,141 @@
+/*
+ * Copyright (c) 2008-2012 Juli Mallett. 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY 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 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	COMMON_ENDIAN_H
+#define	COMMON_ENDIAN_H
+
+#if !defined(BYTE_ORDER) && !defined(LITTLE_ENDIAN) && !defined(BIG_ENDIAN)
+#define	LITTLE_ENDIAN	1234
+#define	BIG_ENDIAN	4321
+#if defined(_LITTLE_ENDIAN)
+#define	BYTE_ORDER	LITTLE_ENDIAN
+#elif defined(_BIG_ENDIAN)
+#define	BYTE_ORDER	BIG_ENDIAN
+#else
+#error "Can't determine host byte order."
+#endif
+#endif
+
+#ifndef	BYTE_ORDER
+#error "BYTE_ORDER must be defined."
+#else
+#if BYTE_ORDER == LITTLE_ENDIAN
+#elif BYTE_ORDER == BIG_ENDIAN
+#else
+#error "Unexpected BYTE_ORDER value."
+#endif
+#endif
+
+struct Endian {
+	static uint16_t swap(const uint16_t& in)
+	{
+		return (((in & 0xff00u) >> 0x08) | ((in & 0x00ffu) << 0x08));
+	}
+
+	static uint32_t swap(const uint32_t& in)
+	{
+		return (((in & 0xff000000u) >> 0x18) |
+			((in & 0x00ff0000u) >> 0x08) |
+			((in & 0x0000ff00u) << 0x08) |
+			((in & 0x000000ffu) << 0x18));
+	}
+
+	static uint64_t swap(const uint64_t& in)
+	{
+		return (((in & 0xff00000000000000ull) >> 0x38) |
+			((in & 0x00ff000000000000ull) >> 0x28) |
+			((in & 0x0000ff0000000000ull) >> 0x18) |
+			((in & 0x000000ff00000000ull) >> 0x08) |
+			((in & 0x00000000ff000000ull) << 0x08) |
+			((in & 0x0000000000ff0000ull) << 0x18) |
+			((in & 0x000000000000ff00ull) << 0x28) |
+			((in & 0x00000000000000ffull) << 0x38));
+	}
+};
+
+struct SwapEndian {
+	template<typename T>
+	static T encode(const T& in)
+	{
+		return (Endian::swap(in));
+	}
+
+	template<typename T>
+	static T decode(const T& in)
+	{
+		return (Endian::swap(in));
+	}
+
+	template<class C, typename T>
+	static void append(C *out, const T& in)
+	{
+		T swapped = encode(in);
+		out->append(&swapped);
+	}
+
+	template<class C, typename T>
+	static void extract(T *out, const C *in)
+	{
+		T wire;
+		in->extract(&wire);
+		*out = decode(wire);
+	}
+};
+
+struct HostEndian {
+	template<typename T>
+	static T encode(const T& in)
+	{
+		return (in);
+	}
+
+	template<typename T>
+	static T decode(const T& in)
+	{
+		return (in);
+	}
+
+	template<class C, typename T>
+	static void append(C *out, const T& in)
+	{
+		out->append(&in);
+	}
+
+	template<class C, typename T>
+	static void extract(T *out, const C *in)
+	{
+		in->extract(out);
+	}
+};
+
+#if BYTE_ORDER == LITTLE_ENDIAN
+typedef	HostEndian	LittleEndian;
+typedef	SwapEndian	BigEndian;
+#elif BYTE_ORDER == BIG_ENDIAN
+typedef	SwapEndian	LittleEndian;
+typedef	HostEndian	BigEndian;
+#endif
+
+#endif /* !COMMON_ENDIAN_H */