initial commit of lk (little kernel) project
diff --git a/lib/lwip/src/include/lwip/api.h b/lib/lwip/src/include/lwip/api.h
new file mode 100644
index 0000000..7f0ad59
--- /dev/null
+++ b/lib/lwip/src/include/lwip/api.h
@@ -0,0 +1,159 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_API_H__
+#define __LWIP_API_H__
+
+#include "lwip/opt.h"
+#include "lwip/pbuf.h"
+#include "lwip/sys.h"
+
+#include "lwip/ip.h"
+
+#include "lwip/raw.h"
+#include "lwip/udp.h"
+#include "lwip/tcp.h"
+
+#include "lwip/err.h"
+
+#define NETCONN_NOCOPY 0x00
+#define NETCONN_COPY   0x01
+
+enum netconn_type {
+  NETCONN_TCP,
+  NETCONN_UDP,
+  NETCONN_UDPLITE,
+  NETCONN_UDPNOCHKSUM,
+  NETCONN_RAW
+};
+
+enum netconn_state {
+  NETCONN_NONE,
+  NETCONN_WRITE,
+  NETCONN_ACCEPT,
+  NETCONN_RECV,
+  NETCONN_CONNECT,
+  NETCONN_CLOSE
+};
+
+enum netconn_evt {
+  NETCONN_EVT_RCVPLUS,
+  NETCONN_EVT_RCVMINUS,
+  NETCONN_EVT_SENDPLUS,
+  NETCONN_EVT_SENDMINUS
+};
+
+struct netbuf {
+  struct pbuf *p, *ptr;
+  struct ip_addr *fromaddr;
+  u16_t fromport;
+  err_t err;
+};
+
+struct netconn {
+  enum netconn_type type;
+  enum netconn_state state;
+  union {
+    struct tcp_pcb *tcp;
+    struct udp_pcb *udp;
+    struct raw_pcb *raw;
+  } pcb;
+  err_t err;
+  sys_mbox_t mbox;
+  sys_mbox_t recvmbox;
+  sys_mbox_t acceptmbox;
+  sys_sem_t sem;
+  int socket;
+  u16_t recv_avail;
+  void (* callback)(struct netconn *, enum netconn_evt, u16_t len);
+};
+
+/* Network buffer functions: */
+struct netbuf *   netbuf_new      (void);
+void              netbuf_delete   (struct netbuf *buf);
+void *            netbuf_alloc    (struct netbuf *buf, u16_t size);
+void              netbuf_free     (struct netbuf *buf);
+void              netbuf_ref      (struct netbuf *buf,
+           void *dataptr, u16_t size);
+void              netbuf_chain    (struct netbuf *head,
+           struct netbuf *tail);
+
+u16_t             netbuf_len      (struct netbuf *buf);
+err_t             netbuf_data     (struct netbuf *buf,
+           void **dataptr, u16_t *len);
+s8_t              netbuf_next     (struct netbuf *buf);
+void              netbuf_first    (struct netbuf *buf);
+
+void              netbuf_copy     (struct netbuf *buf,
+           void *dataptr, u16_t len);
+void              netbuf_copy_partial(struct netbuf *buf, void *dataptr, 
+              u16_t len, u16_t offset);
+struct ip_addr *  netbuf_fromaddr (struct netbuf *buf);
+u16_t             netbuf_fromport (struct netbuf *buf);
+
+/* Network connection functions: */
+struct netconn *  netconn_new     (enum netconn_type type);
+struct
+netconn *netconn_new_with_callback(enum netconn_type t,
+                                   void (*callback)(struct netconn *, enum netconn_evt, u16_t len));
+struct
+netconn *netconn_new_with_proto_and_callback(enum netconn_type t, u16_t proto,
+                                   void (*callback)(struct netconn *, enum netconn_evt, u16_t len));
+err_t             netconn_delete  (struct netconn *conn);
+enum netconn_type netconn_type    (struct netconn *conn);
+err_t             netconn_peer    (struct netconn *conn,
+           struct ip_addr *addr,
+           u16_t *port);
+err_t             netconn_addr    (struct netconn *conn,
+           struct ip_addr **addr,
+           u16_t *port);
+err_t             netconn_bind    (struct netconn *conn,
+           struct ip_addr *addr,
+           u16_t port);
+err_t             netconn_connect (struct netconn *conn,
+           struct ip_addr *addr,
+           u16_t port);
+err_t             netconn_disconnect (struct netconn *conn);
+err_t             netconn_listen  (struct netconn *conn);
+struct netconn *  netconn_accept  (struct netconn *conn);
+struct netbuf *   netconn_recv    (struct netconn *conn);
+err_t             netconn_send    (struct netconn *conn,
+           struct netbuf *buf);
+err_t             netconn_write   (struct netconn *conn,
+           void *dataptr, u16_t size,
+           u8_t copy);
+err_t             netconn_close   (struct netconn *conn);
+
+err_t             netconn_err     (struct netconn *conn);
+
+#endif /* __LWIP_API_H__ */
+
+