-#ifndef ETHERBOOT_BYTESWAP_H
-#define ETHERBOOT_BYTESWAP_H
-
-FILE_LICENCE ( GPL2_OR_LATER );
-
-#include "endian.h"
-#include "bits/byteswap.h"
-
-#define __bswap_constant_16(x) \
- ((uint16_t)((((uint16_t)(x) & 0x00ff) << 8) | \
- (((uint16_t)(x) & 0xff00) >> 8)))
-
-#define __bswap_constant_32(x) \
- ((uint32_t)((((uint32_t)(x) & 0x000000ffU) << 24) | \
- (((uint32_t)(x) & 0x0000ff00U) << 8) | \
- (((uint32_t)(x) & 0x00ff0000U) >> 8) | \
- (((uint32_t)(x) & 0xff000000U) >> 24)))
-
-#define __bswap_constant_64(x) \
- ((uint64_t)((((uint64_t)(x) & 0x00000000000000ffULL) << 56) | \
- (((uint64_t)(x) & 0x000000000000ff00ULL) << 40) | \
- (((uint64_t)(x) & 0x0000000000ff0000ULL) << 24) | \
- (((uint64_t)(x) & 0x00000000ff000000ULL) << 8) | \
- (((uint64_t)(x) & 0x000000ff00000000ULL) >> 8) | \
- (((uint64_t)(x) & 0x0000ff0000000000ULL) >> 24) | \
- (((uint64_t)(x) & 0x00ff000000000000ULL) >> 40) | \
- (((uint64_t)(x) & 0xff00000000000000ULL) >> 56)))
-
-#define __bswap_16(x) \
- ((uint16_t)(__builtin_constant_p(x) ? \
- __bswap_constant_16(x) : \
- __bswap_variable_16(x)))
-
-#define __bswap_32(x) \
- ((uint32_t)(__builtin_constant_p(x) ? \
- __bswap_constant_32(x) : \
- __bswap_variable_32(x)))
-
-#define __bswap_64(x) \
- ((uint64_t)(__builtin_constant_p(x) ? \
- __bswap_constant_64(x) : \
- __bswap_variable_64(x)))
+#ifndef BYTESWAP_H
+#define BYTESWAP_H
+
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
+
+#include <stdint.h>
+#include <endian.h>
+#include <bits/byteswap.h>
+
+/**
+ * Byte-swap a 16-bit constant
+ *
+ * @v value Constant value
+ * @ret swapped Byte-swapped value
+ */
+#define __bswap_constant_16( value ) \
+ ( ( ( (value) & 0x00ff ) << 8 ) | \
+ ( ( (value) & 0xff00 ) >> 8 ) )
+
+/**
+ * Byte-swap a 32-bit constant
+ *
+ * @v value Constant value
+ * @ret swapped Byte-swapped value
+ */
+#define __bswap_constant_32( value ) \
+ ( ( ( (value) & 0x000000ffUL ) << 24 ) | \
+ ( ( (value) & 0x0000ff00UL ) << 8 ) | \
+ ( ( (value) & 0x00ff0000UL ) >> 8 ) | \
+ ( ( (value) & 0xff000000UL ) >> 24 ) )
+
+/**
+ * Byte-swap a 64-bit constant
+ *
+ * @v value Constant value
+ * @ret swapped Byte-swapped value
+ */
+#define __bswap_constant_64( value ) \
+ ( ( ( (value) & 0x00000000000000ffULL ) << 56 ) | \
+ ( ( (value) & 0x000000000000ff00ULL ) << 40 ) | \
+ ( ( (value) & 0x0000000000ff0000ULL ) << 24 ) | \
+ ( ( (value) & 0x00000000ff000000ULL ) << 8 ) | \
+ ( ( (value) & 0x000000ff00000000ULL ) >> 8 ) | \
+ ( ( (value) & 0x0000ff0000000000ULL ) >> 24 ) | \
+ ( ( (value) & 0x00ff000000000000ULL ) >> 40 ) | \
+ ( ( (value) & 0xff00000000000000ULL ) >> 56 ) )
+
+/**
+ * Byte-swap a 16-bit value
+ *
+ * @v value Value
+ * @ret swapped Byte-swapped value
+ */
+#define __bswap_16( value ) \
+ ( __builtin_constant_p (value) ? \
+ ( ( uint16_t ) __bswap_constant_16 ( ( uint16_t ) (value) ) ) \
+ : __bswap_variable_16 (value) )
+#define bswap_16( value ) __bswap_16 (value)
+
+/**
+ * Byte-swap a 32-bit value
+ *
+ * @v value Value
+ * @ret swapped Byte-swapped value
+ */
+#define __bswap_32( value ) \
+ ( __builtin_constant_p (value) ? \
+ ( ( uint32_t ) __bswap_constant_32 ( ( uint32_t ) (value) ) ) \
+ : __bswap_variable_32 (value) )
+#define bswap_32( value ) __bswap_32 (value)
+
+/**
+ * Byte-swap a 64-bit value
+ *
+ * @v value Value
+ * @ret swapped Byte-swapped value
+ */
+#define __bswap_64( value ) \
+ ( __builtin_constant_p (value) ? \
+ ( ( uint64_t ) __bswap_constant_64 ( ( uint64_t ) (value) ) ) \
+ : __bswap_variable_64 (value) )
+#define bswap_64( value ) __bswap_64 (value)