cmds: provide endian helpers when missing

Windows doesn't provide the endian header file, in this case define the
byte order helpers.

Signed-off-by: Daniel Wagner <[email protected]>

Author: igaw

libnvme/src/nvme/cmds.h

@@ -10,10 +10,36 @@
 
 #pragma once
 
-#include <endian.h>
 #include <errno.h>
 #include <string.h>
 
+#ifdef __linux__
+#include <endian.h>
+#else
+#if defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+	#define htobe16(x) (x)
+	#define htobe32(x) (x)
+	#define htobe64(x) (x)
+	#define htole16(x) __builtin_bswap16(x)
+	#define htole32(x) __builtin_bswap32(x)
+	#define htole64(x) __builtin_bswap64(x)
+	#define le16toh(x) __builtin_bswap16(x)
+	#define le32toh(x) __builtin_bswap32(x)
+	#define le64toh(x) __builtin_bswap64(x)
+#else
+	/* Little-endian (most common case for Windows) */
+	#define htobe16(x) __builtin_bswap16(x)
+	#define htobe32(x) __builtin_bswap32(x)
+	#define htobe64(x) __builtin_bswap64(x)
+	#define htole16(x) (x)
+	#define htole32(x) (x)
+	#define htole64(x) (x)
+	#define le16toh(x) (x)
+	#define le32toh(x) (x)
+	#define le64toh(x) (x)
+#endif
+#endif
+
 #include <nvme/ioctl.h>
 #include <nvme/types.h>