[PATCH 2/3] scripts: compiler.h: add Windows support

[Ahmad Fatoum]

We lack endianness conversion functions for Windows. Import them from
the public-domain portable_endian.h[1]. We skip the 64-bit XBox support
though as it's unlikely we'll need to run imx-usb-loader on that
particular game console.

While at it, only define min when it's undefined. This works around one
of the winapi headers indirectly included defining it.

[1]: https://gist.github.com/panzi/6856583

Signed-off-by: Ahmad Fatoum <a.fatoum at pengutronix.de>
---
 scripts/compiler.h | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/scripts/compiler.h b/scripts/compiler.h
index c932f715c551..925cad21b6cf 100644
--- a/scripts/compiler.h
+++ b/scripts/compiler.h
@@ -61,6 +61,37 @@ typedef unsigned int  uint;
 #elif defined(__OpenBSD__) || defined(__FreeBSD__) || \
       defined(__NetBSD__) || defined(__DragonFly__)
 # include <sys/endian.h>
+#elif defined _WIN32
+# if defined(_MSC_VER)
+#  include <stdlib.h>
+#  define htobe16(x) _byteswap_ushort(x)
+#  define htole16(x) (x)
+#  define be16toh(x) _byteswap_ushort(x)
+#  define le16toh(x) (x)
+#  define htobe32(x) _byteswap_ulong(x)
+#  define htole32(x) (x)
+#  define be32toh(x) _byteswap_ulong(x)
+#  define le32toh(x) (x)
+#  define htobe64(x) _byteswap_uint64(x)
+#  define htole64(x) (x)
+#  define be64toh(x) _byteswap_uint64(x)
+#  define le64toh(x) (x)
+# elif defined(__GNUC__) || defined(__clang__)
+#  define htobe16(x) __builtin_bswap16(x)
+#  define htole16(x) (x)
+#  define be16toh(x) __builtin_bswap16(x)
+#  define le16toh(x) (x)
+#  define htobe32(x) __builtin_bswap32(x)
+#  define htole32(x) (x)
+#  define be32toh(x) __builtin_bswap32(x)
+#  define le32toh(x) (x)
+#  define htobe64(x) __builtin_bswap64(x)
+#  define htole64(x) (x)
+#  define be64toh(x) __builtin_bswap64(x)
+#  define le64toh(x) (x)
+#else
+#  error platform not supported
+#endif
 #else /* assume Linux */
 # include <sys/types.h>
 # include <endian.h>
@@ -128,11 +159,13 @@ typedef uint32_t __u32;
 # define be64_to_cpu(x)		(x)
 #endif
 
+#ifndef min
 #define min(x, y) ({                            \
 	typeof(x) _min1 = (x);                  \
 	typeof(y) _min2 = (y);                  \
 	(void) (&_min1 == &_min2);              \
 	_min1 < _min2 ? _min1 : _min2; })
+#endif
 
 static inline void *xmalloc(size_t size)
 {
-- 
2.39.2