[*] Initial commit

lonetix/include/df/sys/endian.h

@@ -0,0 +1,132 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+
+/**
+ * \file sys/endian.h
+ *
+ * Architecture specific byteswap utilities.
+ *
+ * \copyright The DoubleFourteen Code Forge (C) All Rights Reserved
+ * \author    Lorenzo Cogotti
+ */
+
+#ifndef DF_SYS_ENDIAN_H_
+#define DF_SYS_ENDIAN_H_
+
+#include "xpt.h"
+
+#ifdef _MSC_VER
+#include <stdlib.h>  // _byteswap_*()
+#endif
+
+/// Helper `union` to access bit representation of `float`.
+typedef union {
+	float  f32;
+	Uint32 bits;
+} Floatbits;
+
+/// Helper `union` to access bit representation of `double`.
+typedef union {
+	double f64;
+	Uint64 bits;
+} Doublebits;
+
+STATIC_ASSERT(sizeof(Floatbits)  == sizeof(Uint32), "float vs Uint32 size mismatch");
+STATIC_ASSERT(sizeof(Doublebits) == sizeof(Uint64), "double vs Uint64 size mismatch");
+
+/// Swap bytes inside 16-bits word.
+FORCE_INLINE Uint16 bswap16(Uint16 x)
+{
+#ifdef _MSC_VER
+	return _byteswap_ushort(x);
+#elif defined(__GNUC__)
+	return __builtin_bswap16(x);
+#else
+	return BSWAP16(x);
+#endif
+}
+
+/// Swap bytes inside 32-bits dword.
+FORCE_INLINE Uint32 bswap32(Uint32 x)
+{
+#ifdef _MSC_VER
+	return _byteswap_ulong(x);
+#elif defined(__GNUC__)
+	return __builtin_bswap32(x);
+#else
+	return BSWAP32(x);
+#endif
+}
+
+/// Swap bytes inside 64-bits quadword.
+FORCE_INLINE Uint64 bswap64(Uint64 x)
+{
+#ifdef _MSC_VER
+	return _byteswap_uint64(x);
+#elif defined(__GNUC__)
+	return __builtin_bswap64(x);
+#else
+	return BSWAP64(x);
+#endif
+}
+
+/// `bswap16()` if target isn't little-endian.
+FORCE_INLINE Uint16 leswap16(Uint16 x)
+{
+#if EDN_NATIVE == EDN_LE
+	return x;
+#else
+	return bswap16(x);
+#endif
+}
+
+/// `bswap16()` if target isn't big-endian.
+FORCE_INLINE Uint16 beswap16(Uint16 x)
+{
+#if EDN_NATIVE == EDN_BE
+	return x;
+#else
+	return bswap16(x);
+#endif
+}
+
+/// `bswap32()` if target isn't little-endian.
+FORCE_INLINE Uint32 leswap32(Uint32 x)
+{
+#if EDN_NATIVE == EDN_LE
+	return x;
+#else
+	return bswap32(x);
+#endif
+}
+
+/// `bswap32()` if target isn't big-endian.
+FORCE_INLINE Uint32 beswap32(Uint32 x)
+{
+#if EDN_NATIVE == EDN_BE
+	return x;
+#else
+	return bswap32(x);
+#endif
+}
+
+/// `bswap64()` if target isn't little-endian.
+FORCE_INLINE Uint64 leswap64(Uint64 x)
+{
+#if EDN_NATIVE == EDN_LE
+	return x;
+#else
+	return bswap64(x);
+#endif
+}
+
+/// `bswap64()` if target isn't big-endian.
+FORCE_INLINE Uint64 beswap64(Uint64 x)
+{
+#if EDN_NATIVE == EDN_BE
+	return x;
+#else
+	return bswap64(x);
+#endif
+}
+
+#endif