Add lwIP V1.3 files.

Demo/Common/ethernet/lwIP_130/src/netif/loopif.c

@@ -0,0 +1,217 @@
+/**
+ * @file
+ * Loop Interface
+ *
+ */
+
+/*
+ * 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>
+ *
+ */
+#include "lwip/opt.h"
+
+#if LWIP_HAVE_LOOPIF
+
+#include "netif/loopif.h"
+#include "lwip/pbuf.h"
+#include "lwip/snmp.h"
+
+#include <string.h>
+
+#if !LWIP_LOOPIF_MULTITHREADING
+
+#include "lwip/sys.h"
+#include "lwip/mem.h"
+
+/* helper struct for the linked list of pbufs */
+struct loopif_private {
+  struct pbuf *first;
+  struct pbuf *last;
+};
+
+/**
+ * Call loopif_poll() in the main loop of your application. This is to prevent
+ * reentering non-reentrant functions like tcp_input(). Packets passed to
+ * loopif_output() are put on a list that is passed to netif->input() by
+ * loopif_poll().
+ *
+ * @param netif the lwip network interface structure for this loopif
+ */
+void
+loopif_poll(struct netif *netif)
+{
+  SYS_ARCH_DECL_PROTECT(lev);
+  struct pbuf *in, *in_end;
+  struct loopif_private *priv = (struct loopif_private*)netif->state;
+
+  LWIP_ERROR("priv != NULL", (priv != NULL), return;);
+
+  do {
+    /* Get a packet from the list. With SYS_LIGHTWEIGHT_PROT=1, this is protected */
+    SYS_ARCH_PROTECT(lev);
+    in = priv->first;
+    if(in) {
+      in_end = in;
+      while(in_end->len != in_end->tot_len) {
+        LWIP_ASSERT("bogus pbuf: len != tot_len but next == NULL!", in_end->next != NULL);
+        in_end = in_end->next;
+      }
+      /* 'in_end' now points to the last pbuf from 'in' */
+      if(in_end == priv->last) {
+        /* this was the last pbuf in the list */
+        priv->first = priv->last = NULL;
+      } else {
+        /* pop the pbuf off the list */
+        priv->first = in_end->next;
+        LWIP_ASSERT("should not be null since first != last!", priv->first != NULL);
+      }
+    }
+    SYS_ARCH_UNPROTECT(lev);
+  
+    if(in != NULL) {
+      if(in_end->next != NULL) {
+        /* De-queue the pbuf from its successors on the 'priv' list. */
+        in_end->next = NULL;
+      }
+      if(netif->input(in, netif) != ERR_OK) {
+        pbuf_free(in);
+      }
+      /* Don't reference the packet any more! */
+      in = NULL;
+      in_end = NULL;
+    }
+  /* go on while there is a packet on the list */
+  } while(priv->first != NULL);
+}
+#endif /* LWIP_LOOPIF_MULTITHREADING */
+
+/**
+ * Send an IP packet over the loopback interface.
+ * The pbuf is simply copied and handed back to netif->input.
+ * In multithreaded mode, this is done directly since netif->input must put
+ * the packet on a queue.
+ * In callback mode, the packet is put on an internal queue and is fed to
+ * netif->input by loopif_poll().
+ *
+ * @param netif the lwip network interface structure for this loopif
+ * @param p the (IP) packet to 'send'
+ * @param ipaddr the ip address to send the packet to (not used for loopif)
+ * @return ERR_OK if the packet has been sent
+ *         ERR_MEM if the pbuf used to copy the packet couldn't be allocated
+ */
+static err_t
+loopif_output(struct netif *netif, struct pbuf *p,
+       struct ip_addr *ipaddr)
+{
+#if !LWIP_LOOPIF_MULTITHREADING
+  SYS_ARCH_DECL_PROTECT(lev);
+  struct loopif_private *priv;
+  struct pbuf *last;
+#endif /* LWIP_LOOPIF_MULTITHREADING */
+  struct pbuf *r;
+  err_t err;
+
+  LWIP_UNUSED_ARG(ipaddr);
+
+  /* Allocate a new pbuf */
+  r = pbuf_alloc(PBUF_RAW, p->tot_len, PBUF_RAM);
+  if (r == NULL) {
+    return ERR_MEM;
+  }
+
+  /* Copy the whole pbuf queue p into the single pbuf r */
+  if ((err = pbuf_copy(r, p)) != ERR_OK) {
+    pbuf_free(r);
+    r = NULL;
+    return err;
+  }
+
+#if LWIP_LOOPIF_MULTITHREADING
+  /* Multithreading environment, netif->input() is supposed to put the packet
+     into a mailbox, so we can safely call it here without risking to re-enter
+     functions that are not reentrant (TCP!!!) */
+  if(netif->input(r, netif) != ERR_OK) {
+    pbuf_free(r);
+    r = NULL;
+  }
+#else /* LWIP_LOOPIF_MULTITHREADING */
+  /* Raw API without threads: put the packet on a linked list which gets emptied
+     through calling loopif_poll(). */
+  priv = (struct loopif_private*)netif->state;
+
+  /* let last point to the last pbuf in chain r */
+  for (last = r; last->next != NULL; last = last->next);
+  SYS_ARCH_PROTECT(lev);
+  if(priv->first != NULL) {
+    LWIP_ASSERT("if first != NULL, last must also be != NULL", priv->last != NULL);
+    priv->last->next = r;
+    priv->last = last;
+  } else {
+    priv->first = r;
+    priv->last = last;
+  }
+  SYS_ARCH_UNPROTECT(lev);
+#endif /* LWIP_LOOPIF_MULTITHREADING */
+
+  return ERR_OK;    
+}
+
+/**
+ * Initialize a lwip network interface structure for a loopback interface
+ *
+ * @param netif the lwip network interface structure for this loopif
+ * @return ERR_OK if the loopif is initialized
+ *         ERR_MEM if private data couldn't be allocated
+ */
+err_t
+loopif_init(struct netif *netif)
+{
+#if !LWIP_LOOPIF_MULTITHREADING
+  struct loopif_private *priv;
+
+  priv = (struct loopif_private*)mem_malloc(sizeof(struct loopif_private));
+  if(priv == NULL) 
+    return ERR_MEM;
+  priv->first = priv->last = NULL;
+  netif->state = priv;
+#endif /* LWIP_LOOPIF_MULTITHREADING */
+
+  /* initialize the snmp variables and counters inside the struct netif
+   * ifSpeed: no assumption can be made!
+   */
+  NETIF_INIT_SNMP(netif, snmp_ifType_softwareLoopback, 0);
+
+  netif->name[0] = 'l';
+  netif->name[1] = 'o';
+  netif->output = loopif_output;
+  return ERR_OK;
+}
+
+#endif /* LWIP_HAVE_LOOPIF */