add platform.h to easily check for different systems and archs

octa/platform.h

@@ -0,0 +1,72 @@
+/* Platform specific definitions for OctaSTD.
+ *
+ * This file is part of OctaSTD. See COPYING.md for futher information.
+ */
+
+#ifndef OCTA_PLATFORM_H
+#define OCTA_PLATFORM_H
+
+#if defined(WIN32) || defined(_WIN32) || (defined(__WIN32) && !defined(__CYGWIN__))
+#  define OCTA_PLATFORM_WIN32 1
+#  if defined(WIN64) || defined(_WIN64)
+#    define OCTA_PLATFORM_WIN64 1
+#  endif
+#else
+#  define OCTA_PLATFORM_POSIX 1
+#  if defined(__linux__)
+#    define OCTA_PLATFORM_LINUX 1
+#  endif
+#  if defined(__APPLE__)
+#    define OCTA_PLATFORM_OSX 1
+#  endif
+#  if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
+#    define OCTA_PLATFORM_FREEBSD 1
+#    define OCTA_PLATFORM_BSD 1
+#  endif
+#  if defined(__NetBSD__)
+#    define OCTA_PLATFORM_NETBSD 1
+#    define OCTA_PLATFORM_BSD 1
+#  endif
+#  if defined(__OpenBSD__)
+#    define OCTA_PLATFORM_OPENBSD 1
+#    define OCTA_PLATFORM_BSD 1
+#  endif
+#  if defined(__DragonFly__)
+#    define OCTA_PLATFORM_DRAGONFLYBSD 1
+#    define OCTA_PLATFORM_BSD 1
+#  endif
+#  if defined(sun) || defined(__sun)
+#    define OCTA_PLATFORM_SOLARIS 1
+#  endif
+#endif
+
+#if defined(__clang__)
+#  define OCTA_TOOLCHAIN_CLANG 1
+#endif
+
+#if defined(__GNUC__)
+#  define OCTA_TOOLCHAIN_GNU 1
+#endif
+
+#if defined(_MSC_VER)
+#  define OCTA_TOOLCHAIN_MSVC 1
+#endif
+
+#define OCTA_ENDIAN_LIL 1234
+#define OCTA_ENDIAN_BIG 4321
+
+#ifdef OCTA_PLATFORM_LINUX
+#  include <endian.h>
+#  define OCTA_BYTE_ORDER __BYTE_ORDER
+#else
+#  if defined(__BIG_ENDIAN__) || defined(__ARMEB__) || defined(__THUMBEB__) || \
+      defined(__AARCH64EB__)  || defined(__MIPSEB__) || defined(__MIPSEB) || \
+      defined(_MIPSEB) || defined(__ppc__) || defined(__POWERPC__) || \
+      defined(_M_PPC) || defined(__sparc__)
+#    define OCTA_BYTE_ORDER OCTA_ENDIAN_BIG
+#  else
+#    define OCTA_BYTE_ORDER OCTA_ENDIAN_LIL
+#  endif
+#endif
+
+#endif