first usable version of kernel and commands

After an year of hard work, this is a first "usable" version of Jehanne.

sys/src/kern/port/net.c

@@ -0,0 +1,65 @@
+#include	"u.h"
+#include	"../port/lib.h"
+#include	"mem.h"
+#include	"dat.h"
+#include	"fns.h"
+#include	"../port/error.h"
+
+void
+hnputv(void *p, uint64_t v)
+{
+	uint8_t *a;
+
+	a = p;
+	hnputl(a, v>>32);
+	hnputl(a+4, v);
+}
+
+void
+hnputl(void *p, uint32_t v)
+{
+	uint8_t *a;
+
+	a = p;
+	a[0] = v>>24;
+	a[1] = v>>16;
+	a[2] = v>>8;
+	a[3] = v;
+}
+
+void
+hnputs(void *p, uint16_t v)
+{
+	uint8_t *a;
+
+	a = p;
+	a[0] = v>>8;
+	a[1] = v;
+}
+
+uint64_t
+nhgetv(void *p)
+{
+	uint8_t *a;
+
+	a = p;
+	return ((int64_t)nhgetl(a) << 32) | nhgetl(a+4);
+}
+
+uint32_t
+nhgetl(void *p)
+{
+	uint8_t *a;
+
+	a = p;
+	return (a[0]<<24)|(a[1]<<16)|(a[2]<<8)|(a[3]<<0);
+}
+
+uint16_t
+nhgets(void *p)
+{
+	uint8_t *a;
+
+	a = p;
+	return (a[0]<<8)|(a[1]<<0);
+}