date and time created 81/11/29 22:18:03 by wnj

SCCS-vsn: sys/net/if_loop.c 4.1

diff --git a/usr/src/sys/net/if_loop.c b/usr/src/sys/net/if_loop.c
new file mode 100644 (file)
index 0000000..8dd37fd
--- /dev/null
+++ b/usr/src/sys/net/if_loop.c
@@ -0,0 +1,59 @@
+/*     if_loop.c       4.1     81/11/29        */
+
+/*
+ * Loopback interface driver for protocol testing and timing.
+ */
+
+#include "../h/param.h"
+#include "../h/systm.h"
+#include "../h/mbuf.h"
+#include "../h/socket.h"
+#include "../net/in.h"
+#include "../net/in_systm.h"
+#include "../net/if.h"
+#include "../net/ip.h"
+#include "../net/ip_var.h"
+#include "../h/mtpr.h"
+
+#define        LONET   254
+#define        LOMTU   1024
+
+struct ifnet loif;
+int    looutput();
+
+loattach()
+{
+       register struct ifnet *ifp = &loif;
+
+       ifp->if_mtu = LOMTU;
+       ifp->if_net = LONET;
+       ifp->if_output = looutput;
+       ifp->if_next = ifnet;
+       ifnet = ifp;
+}
+
+looutput(ifp, m0, pf)
+       struct ifnet *ifp;
+       struct mbuf *m0;
+       int pf;
+{
+       int s = splimp();
+
+       switch (pf) {
+
+#ifdef INET
+       case PF_INET:
+               IF_ENQUEUE(&ipintrq, m0);
+               setipintr();
+               break;
+#endif
+
+       default:
+               splx(s);
+               printf("lo%d: can't encapsulate pf%d\n", ifp->if_unit, pf);
+               m_freem(m0);
+               return (0);
+       }
+       splx(s);
+       return (1);
+}