add directory study

study/linux-travel/MINIX-1.5/1.5/Source/amoeba/kernel/byteorder.h

@@ -0,0 +1,21 @@
+/*
+ * set of macros to do inplace byteorder changes
+ * The dec_* routines decode a short (_s) or long (_l) from little endian(_le)
+ * or bigendian(_be) to native format.
+ * The enc_* are similar for native to net format
+ */
+
+
+/* littleendian version for ibm pc */
+
+#define dec_s_le(s)	/* nothing */
+#define dec_s_be(s)	(*(s))=((((*(s))>>8)&0xFF)|(((*(s))&0xFF)<<8))
+
+#define dec_l_le(l)	/* nothing */
+#define dec_l_be(l)	(*(l))=((((*(l))>>24)&0xFF)|(((*(l))>>8)&0xFF00)|(((*(l))<<8)&0xFF0000)|(((*(l))<<24)&0xFF000000))
+
+#define enc_s_le(s)	/* nothing */
+#define enc_s_be(s)	dec_s_be(s)
+
+#define enc_l_le(l)	/* nothing */
+#define enc_l_be(l)	dec_l_be(l)