Miguel Ruiz
SDL standard library
Diff: SDL_endian.h
- Revision:
- 0:dda4f4550403
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/SDL_endian.h Wed Sep 07 18:46:53 2016 +0000
@@ -0,0 +1,239 @@
+/*
+ Simple DirectMedia Layer
+ Copyright (C) 1997-2014 Sam Lantinga <slouken@libsdl.org>
+
+ This software is provided 'as-is', without any express or implied
+ warranty. In no event will the authors be held liable for any damages
+ arising from the use of this software.
+
+ Permission is granted to anyone to use this software for any purpose,
+ including commercial applications, and to alter it and redistribute it
+ freely, subject to the following restrictions:
+
+ 1. The origin of this software must not be misrepresented; you must not
+ claim that you wrote the original software. If you use this software
+ in a product, an acknowledgment in the product documentation would be
+ appreciated but is not required.
+ 2. Altered source versions must be plainly marked as such, and must not be
+ misrepresented as being the original software.
+ 3. This notice may not be removed or altered from any source distribution.
+*/
+
+/**
+ * \file SDL_endian.h
+ *
+ * Functions for reading and writing endian-specific values
+ */
+
+#ifndef _SDL_endian_h
+#define _SDL_endian_h
+
+#include "SDL_stdinc.h"
+
+/**
+ * \name The two types of endianness
+ */
+/* @{ */
+#define SDL_LIL_ENDIAN 1234
+#define SDL_BIG_ENDIAN 4321
+/* @} */
+
+#ifndef SDL_BYTEORDER /* Not defined in SDL_config.h? */
+#ifdef __linux__
+#include <endian.h>
+#define SDL_BYTEORDER __BYTE_ORDER
+#else /* __linux __ */
+#if defined(__hppa__) || \
+ defined(__m68k__) || defined(mc68000) || defined(_M_M68K) || \
+ (defined(__MIPS__) && defined(__MISPEB__)) || \
+ defined(__ppc__) || defined(__POWERPC__) || defined(_M_PPC) || \
+ defined(__sparc__)
+#define SDL_BYTEORDER SDL_BIG_ENDIAN
+#else
+#define SDL_BYTEORDER SDL_LIL_ENDIAN
+#endif
+#endif /* __linux __ */
+#endif /* !SDL_BYTEORDER */
+
+
+#include "begin_code.h"
+/* Set up for C function definitions, even when using C++ */
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * \file SDL_endian.h
+ */
+#if defined(__GNUC__) && defined(__i386__) && \
+ !(__GNUC__ == 2 && __GNUC_MINOR__ == 95 /* broken gcc version */)
+SDL_FORCE_INLINE Uint16
+SDL_Swap16(Uint16 x)
+{
+ __asm__("xchgb %b0,%h0": "=q"(x):"0"(x));
+ return x;
+}
+#elif defined(__GNUC__) && defined(__x86_64__)
+SDL_FORCE_INLINE Uint16
+SDL_Swap16(Uint16 x)
+{
+ __asm__("xchgb %b0,%h0": "=Q"(x):"0"(x));
+ return x;
+}
+#elif defined(__GNUC__) && (defined(__powerpc__) || defined(__ppc__))
+SDL_FORCE_INLINE Uint16
+SDL_Swap16(Uint16 x)
+{
+ int result;
+
+ __asm__("rlwimi %0,%2,8,16,23": "=&r"(result):"0"(x >> 8), "r"(x));
+ return (Uint16)result;
+}
+#elif defined(__GNUC__) && (defined(__M68000__) || defined(__M68020__)) && !defined(__mcoldfire__)
+SDL_FORCE_INLINE Uint16
+SDL_Swap16(Uint16 x)
+{
+ __asm__("rorw #8,%0": "=d"(x): "0"(x):"cc");
+ return x;
+}
+#else
+SDL_FORCE_INLINE Uint16
+SDL_Swap16(Uint16 x)
+{
+ return SDL_static_cast(Uint16, ((x << 8) | (x >> 8)));
+}
+#endif
+
+#if defined(__GNUC__) && defined(__i386__)
+SDL_FORCE_INLINE Uint32
+SDL_Swap32(Uint32 x)
+{
+ __asm__("bswap %0": "=r"(x):"0"(x));
+ return x;
+}
+#elif defined(__GNUC__) && defined(__x86_64__)
+SDL_FORCE_INLINE Uint32
+SDL_Swap32(Uint32 x)
+{
+ __asm__("bswapl %0": "=r"(x):"0"(x));
+ return x;
+}
+#elif defined(__GNUC__) && (defined(__powerpc__) || defined(__ppc__))
+SDL_FORCE_INLINE Uint32
+SDL_Swap32(Uint32 x)
+{
+ Uint32 result;
+
+ __asm__("rlwimi %0,%2,24,16,23": "=&r"(result):"0"(x >> 24), "r"(x));
+ __asm__("rlwimi %0,%2,8,8,15": "=&r"(result):"0"(result), "r"(x));
+ __asm__("rlwimi %0,%2,24,0,7": "=&r"(result):"0"(result), "r"(x));
+ return result;
+}
+#elif defined(__GNUC__) && (defined(__M68000__) || defined(__M68020__)) && !defined(__mcoldfire__)
+SDL_FORCE_INLINE Uint32
+SDL_Swap32(Uint32 x)
+{
+ __asm__("rorw #8,%0\n\tswap %0\n\trorw #8,%0": "=d"(x): "0"(x):"cc");
+ return x;
+}
+#else
+SDL_FORCE_INLINE Uint32
+SDL_Swap32(Uint32 x)
+{
+ return SDL_static_cast(Uint32, ((x << 24) | ((x << 8) & 0x00FF0000) |
+ ((x >> 8) & 0x0000FF00) | (x >> 24)));
+}
+#endif
+
+#if defined(__GNUC__) && defined(__i386__)
+SDL_FORCE_INLINE Uint64
+SDL_Swap64(Uint64 x)
+{
+ union
+ {
+ struct
+ {
+ Uint32 a, b;
+ } s;
+ Uint64 u;
+ } v;
+ v.u = x;
+ __asm__("bswapl %0 ; bswapl %1 ; xchgl %0,%1": "=r"(v.s.a), "=r"(v.s.b):"0"(v.s.a),
+ "1"(v.s.
+ b));
+ return v.u;
+}
+#elif defined(__GNUC__) && defined(__x86_64__)
+SDL_FORCE_INLINE Uint64
+SDL_Swap64(Uint64 x)
+{
+ __asm__("bswapq %0": "=r"(x):"0"(x));
+ return x;
+}
+#else
+SDL_FORCE_INLINE Uint64
+SDL_Swap64(Uint64 x)
+{
+ Uint32 hi, lo;
+
+ /* Separate into high and low 32-bit values and swap them */
+ lo = SDL_static_cast(Uint32, x & 0xFFFFFFFF);
+ x >>= 32;
+ hi = SDL_static_cast(Uint32, x & 0xFFFFFFFF);
+ x = SDL_Swap32(lo);
+ x <<= 32;
+ x |= SDL_Swap32(hi);
+ return (x);
+}
+#endif
+
+
+SDL_FORCE_INLINE float
+SDL_SwapFloat(float x)
+{
+ union
+ {
+ float f;
+ Uint32 ui32;
+ } swapper;
+ swapper.f = x;
+ swapper.ui32 = SDL_Swap32(swapper.ui32);
+ return swapper.f;
+}
+
+
+/**
+ * \name Swap to native
+ * Byteswap item from the specified endianness to the native endianness.
+ */
+/* @{ */
+#if SDL_BYTEORDER == SDL_LIL_ENDIAN
+#define SDL_SwapLE16(X) (X)
+#define SDL_SwapLE32(X) (X)
+#define SDL_SwapLE64(X) (X)
+#define SDL_SwapFloatLE(X) (X)
+#define SDL_SwapBE16(X) SDL_Swap16(X)
+#define SDL_SwapBE32(X) SDL_Swap32(X)
+#define SDL_SwapBE64(X) SDL_Swap64(X)
+#define SDL_SwapFloatBE(X) SDL_SwapFloat(X)
+#else
+#define SDL_SwapLE16(X) SDL_Swap16(X)
+#define SDL_SwapLE32(X) SDL_Swap32(X)
+#define SDL_SwapLE64(X) SDL_Swap64(X)
+#define SDL_SwapFloatLE(X) SDL_SwapFloat(X)
+#define SDL_SwapBE16(X) (X)
+#define SDL_SwapBE32(X) (X)
+#define SDL_SwapBE64(X) (X)
+#define SDL_SwapFloatBE(X) (X)
+#endif
+/* @} *//* Swap to native */
+
+/* Ends C function definitions when using C++ */
+#ifdef __cplusplus
+}
+#endif
+#include "close_code.h"
+
+#endif /* _SDL_endian_h */
+
+/* vi: set ts=4 sw=4 expandtab: */