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diff --git a/lib/byteswap_.h b/lib/byteswap_.h
index dede8a109dc2e4aeabf05727ac268289266f2545..3fee78f237aa6dfb92c935c50922b5b533291641 100644 (file)
--- a/lib/byteswap_.h
+++ b/lib/byteswap_.h
@@ -18,19 +18,27 @@
 
 #ifndef _BYTESWAP_H
 
+/* Given an unsigned 16-bit argument X, return the value corresponding to
+   X with reversed byte order.  */
 #define bswap_16(x) ((((x) & 0x00FF) << 8) | \
-                     (((x) & 0xFF00) >> 8))
+                    (((x) & 0xFF00) >> 8))
+
+/* Given an unsigned 32-bit argument X, return the value corresponding to
+   X with reversed byte order.  */
 #define bswap_32(x) ((((x) & 0x000000FF) << 24) | \
-                     (((x) & 0x0000FF00) << 8) | \
-                     (((x) & 0x00FF0000) << 8) | \
-                     (((x) & 0xFF000000) >> 24))
+                    (((x) & 0x0000FF00) << 8) | \
+                    (((x) & 0x00FF0000) << 8) | \
+                    (((x) & 0xFF000000) >> 24))
+
+/* Given an unsigned 64-bit argument X, return the value corresponding to
+   X with reversed byte order.  */
 #define bswap_64(x) ((((x) & 0x00000000000000FFULL) << 56) | \
-                     (((x) & 0x000000000000FF00ULL) << 40) | \
-                     (((x) & 0x0000000000FF0000ULL) << 24) | \
-                     (((x) & 0x00000000FF000000ULL) << 8) | \
+                    (((x) & 0x000000000000FF00ULL) << 40) | \
+                    (((x) & 0x0000000000FF0000ULL) << 24) | \
+                    (((x) & 0x00000000FF000000ULL) << 8) | \
                     (((x) & 0x000000FF00000000ULL) >> 8) | \
-                     (((x) & 0x0000FF0000000000ULL) >> 24) | \
-                     (((x) & 0x00FF000000000000ULL) >> 40) | \
-                     (((x) & 0xFF00000000000000ULL) >> 56))
+                    (((x) & 0x0000FF0000000000ULL) >> 24) | \
+                    (((x) & 0x00FF000000000000ULL) >> 40) | \
+                    (((x) & 0xFF00000000000000ULL) >> 56))
 
 #endif