working on lwip

mission/netif/slipif.h

@@ -0,0 +1,15 @@
+#pragma once
+
+#include "lwip/opt.h"
+#include "lwip/netif.h"
+
+struct slipif_priv {
+  int fd;
+  /* q is the whole pbuf chain for a packet, p is the current pbuf in the chain */
+  struct pbuf *p, *q;
+  u8_t state;
+  u16_t i, recved;
+};
+
+err_t slipif_init(struct netif * netif);
+void slipif_poll(struct netif *netif);